Water Assisted Injection Moulding: a Study on the Influence of Melt and Process Parameters on the Residual Wall Thickness and the Occurrence of Part Defects for Pa6.

KATHOLIEKE HOGESCHOOL LIMBURG Departement Industriele Wetenschappen en Technologie Water Assisted Injection Moulding: A Study on the Influence of Melt and Process Parameters on the Residual Wall Thickness and the Occurrence of Part Defects for PA6. Gielen Bjorn, Heynickx Lien, Van den Brink Dominique, Vandersteegen Jochen Water Assisted Injection Moulding: A Study on the Influence of Melt and Process Parameters on the Residual Wall Thickness and the Occurrence of Part Defects for PA6. Gielen Bjorn, Heynickx Lien, Van den Brink Dominique, Vandersteegen Jochen Received 7 March 2011 Abstract Although water assisted injection moulding is a relatively new and advanced technique to produce hollow parts, several problems which reduce the product quality can occur. Namely, water inclusions in the wall, severe fingering and double wall defects reduce the product part stiffness. This study investigated the effect of the process parameters water volume flow rate, water injection delay time and melt temperature on the part defects to obtain a better understanding of the formation of these part defects. The effect on the residual wall thickness and the weight of the products was also investigated. Three materials were used: two polyamides and one polypropylene as a reference. The experiments were carried out on an injection moulding machine equipped with a water-injection unit to produce hollow handles. The parts were weighed before and after drying, their wall thickness was measured and their percentage of defects was calculated in order to determine the influence of the processing parameters. IR images and pressure profiles ware also used to investigate possible detection methods for part defects. It was found that all the investigated parameters have a significant influence on the residual wall thickness and part defects. Their ‘ideal’ settings depend on the material and the desired properties since small wall thicknesses and few part defects do not always correspond. IR images can give an indication for the presence of defects, but the internal structure of the surface can not be examined using this technique. Key words: water assisted injection moulding, polyamide, processing parameters, residual wall thickness, fingering, double wall 1. 1. Introduction The development of the water assisted injection moulding (WAIM) technique has led to a breakthrough in the manufacturing of hollow or partly hollow plastic parts, which is not possible with the conventional injection moulding process [1] [2]. These hollow parts are characterised by the lighter weight of the products, relatively lower resin costs per part and less shrinkage and warpage compared to conventional moulded products [3]. Several techniques are available for the production of hollow parts. Two of the most important techniques for hollow parts are gas assisted injection moulding (GAIM) and water assisted injection moulding (WAIM). The principle of water assisted injection moulding is basically similar to gas assisted injection moulding, but the use of water has some interesting advantages over gas assisted injection moulding such as a shorter cycle time and an average smaller residual wall thickness of the products. This is due to the fact that the thermal conductivity and the heat capacity of water are respectively 40 and 4 times greater than those of gas [1], providing a better cooling of the part and therefore a faster production. Water assisted injection moulding is better to mould larger parts with a smaller residual wall thickness. Another advantage of water assisted injection moulding is the absence of the foaming phenomenon in the internal surface which can occur by using gas assisted injection moulding , since water does not dissolve or diffuse in the polymer melt during injection moulding. Disadvantages of water assisted injection moulding are part defects such as fingering and double wall arising in the internal surface. Also, the process is more complex so experience with conventional injection moulding is no guarantee for understanding water assisted injection moulding. The control f the process is much more critical, the design of the mould is more complicated and requires more knowledge of the dynamic interaction between the polymer and the filling water [4]. In addition, new water related processing parameters (water pressure, water injection delay time, water temperature, †¦ ) are involved and require proper adjustment [5]. The technology can be used to mould a large variety of polymers, includi ng glass fibre reinforced composites. Liu [6] reported the successful moulding of PP, PE, ABS and glass fibre filled polyamide 6 (PA6) composites with water assisted injection moulding. According to our investigation, few researchers have described the moulding of pure polyamide 6 with the water assisted injection moulding technique. By understanding the water assisted injection moulding process for this polymer, one is able to optimize the production and improve the product quality of PA6 parts. The water assisted injection moulding process can be applied in four variations [1] [6], which differ by the amount of injected polymer and introduction and evacuation of the water. In the short shot moulding process the cavity is first partially filled with polymer and in the next sequence, highly pressurised water is injected into the polymer core. The pressure is maintained during the cooling sequence to minimize the shrinkage and to further cool down the part. After cooling, the water is evacuated and the part is ejected. This technique is useful for thick parts, but the important limitation is the switchover mark on the surface [7]. This limitation can be eliminated by using the full shot moulding process in which the cavity is first completely filled with polymer. Next, the injection of water pushes the melt into a cavity positioned outside the cavity of the product. This overspill cavity arises by pulling back a core to enlarge the mould cavity for the overspill polymer which has to be removed from the product afterwards. Full shot moulding makes it possible to mould parts with a more uniform residual wall thickness through the end of the part in comparison to short shot moulded parts. Michaeli et al. [6] stated that the melt-push-back process is also capable to produce parts with a more uniform residual wall thickness distribution. In this process the water is injected in the reversed direction of the polymer injection and pushes the excess of melt back into the plasticizing unit. Finally, the core-pulling process uses a series of steel cores that are pulled back during water injection to increase the cavity volume and the product volume. This method produces parts with more uniform internal profiles in comparison to the former mentioned techniques. The investigated polymer, polyamide 6, is a semi-crystalline material that is classified as an engineering plastic. Beneficial properties of polyamide 6 over a wide range of temperatures and humidity are its high strength, high stiffness and toughness, good wear and abrasion resistance, low coefficient of friction and good chemical and electrical resistance [8], [9], [10], [11]. Further modification can be obtained by adding additives like fillers and plasticizers. Fillers achieve a better strength and stiffness, plasticizers cause higher toughness [12], [13]. Modification of the molecular weight has also a distinguishable influence on the polymer properties. The main drawback of polyamide 6 is the high moisture absorption affecting the rheological properties and deteriorating the processability. High moisture absorption causes part defects and results in a bad internal surface quality reducing the stiffness of the end product [14], [15], [16]. The absorbed water in the polymer has two important roles. Firstly, the water molecules act as plasticizers reducing the hydrogen bond interactions between the polyamide chains. Secondly, due to the hygroscopic nature of polyamide 6, the absorbed water influences the condensation reaction equilibrium depending on the initial moisture content [17], [18]. If the moisture content is less than prescribed thermodynamically, the reaction proceeds towards further condensation and an increase in molecular weight, increasing the viscosity exponentially. If the moisture content is higher than determined by the equilibrium, a hydrolysis reaction occurs. This causes a decrease in viscosity as well as degradation of the polymer. To properly process polyamide 6, the pellets are preferably dried to small moisture levels. Possible part defects that may occur in water assisted injection moulding are fingering and double wall. Liu and Lin [19], [20] investigated the problem of fingering in water assisted injection moulded composites. The fingering phenomenon comprises the non-uniformly penetration of water bubbles or steam into the polymer wall outside the designed water channels causing the formation of finger-shaped branches and small cavities in the polymer wall, which lead to a bad internal surface quality and a reduced part stiffness of the end product. Fingering depends on the dimension of the part: thick parts usually exhibit less fingering pattern than thin parts. Three factors might affect the formation of fingering. The first one is shrinkage of the polymer during cooling. During post-filling, the polymer undergoes volumetric shrinkage allowing water to penetrate into the parts. The more the polymer shrinks, the more water will penetrate into the part and causes fingering. However, this statement is in contradiction with the statement that thick parts exhibit less fingering, so research is necessary to investigate which conclusion is relevant for PA6. Shrinkage also depends on the crystallinity of the polymer. PA6 is a crystalline polymer and thus expected to show more shrinkage than an amorphous polymer. Also, water injection moulded parts show more fingering than gas injection moulded parts since water has a higher cooling capacity than gas and has a higher cooling rate of the polymer. This leads to a greater non-uniform temperature distribution in the polymer material which worsens the uniformity of water penetration inside the parts, resulting in fingering [20]. This is equal to the statement that more shrinkage leads to more fingering. The second factor is the viscosity of the polymer melt. During water injection, water follows the path with the least resistance. While the water enters into the mould cavity, it cools the polymer melt and increases the viscosity. It then becomes more difficult for the water to penetrate into the core of the parts. The third factor is the flow resistance in the channel and in the polymer. The higher the flow resistance in the channel and the lower the flow resistance in the polymer, the more water fingering will be induced. The researchers [19] concluded that water fingering worsens when a combination of a higher water pressure, a smaller melt short shot size and a shorter water injection delay time is used. Other parameters which need to be paid attention to are the temperatures of the melt, the mould and the water. Increasing these parameters decreases the cooling rate and the viscosity and results in more fingering because it is easier for water to penetrate in the part. Another possible part defect in water assisted injection moulding is double wall [22]. Double wall is the appearance of a second polymer wall inside the hollow product which deforms the wall significantly. During the water hold time water inclusions develop in the wall. The double wall is caused by the pressure drop after the water hold time. The water in the inclusions becomes steam and expands the internal material surface causing a second wall in the polymer. Two important parameters are responsible for the forming of double wall. The first parameter is the water hold time which should be minimized in order to eliminate double wall. Increasing the water hold time compensates the shrinkage in the wall but enlarge the water inclusions in the wall worsening the double wall. The second parameter is the volume flow rate. Increasing the volume flow rate causes more double wall because more water penetrates in the polymer forming water inclusions which expand into double walls after the water hold time. There is not much known about the phenomenon of double wall. A lot of investigators do not even make a difference between fingering and double wall and characterize it as the same part defect. Hollow parts are mainly characterized by their residual wall thickness that should be minimized in order to obtain a good product quality with minimal defects. A decline in wall thickness is mainly obtained by choosing water assisted injection moulding instead of gas assisted injection moulding [4]. However, Michaeli et al. [22] concluded that in some cases gas assisted injection moulding yields parts with a smaller residual wall thickness. Several process settings can be applied for water assisted injection moulding, each having an influence on the residual wall thickness. Huang and Deng [23] concluded that besides the short shot size there are two other main parameters affecting the residual wall thickness in polypropylene samples. The first parameter is the melt temperature. Increasing the melt temperature leads to reduction of the solidified layer thickness and thus to a decrease in wall thickness. The second parameter is the water injection delay time. When increasing the water injection delay time, the residual wall thickness exhibits an increment because the solidified layer of the melt becomes thicker. Liu and Wu [24] researched the effect of the injection pin on the residual wall thickness distribution. In their research they concluded that a pin consisting of a sintered porous surface can mould large parts with a more uniform residual wall thickness distribution. Application of this high flow rate pin could significantly improve the product quality in terms of smaller wall thickness. The non-uniformity of the residual wall thickness distribution usually occurring in curved product sections, was found to be less in water assisted injection moulded parts than in gas assisted injection moulded parts. Fluids try to follow the path with the least resistance; this is the shortest path. However, water has a higher mass inertion than gas and therefore gives a better concentricity of the residual wall thickness over a cross-section. The uniformity of the residual wall thickness could be improved by adopting different mould temperatures [25]. In order to mould PA6 parts with high product quality using WAIM, one has to apply the optimal settings to reduce the part defects (fingering and double wall) and decline the residual wall thickness. The water injection delay time influences fingering and the residual wall thickness. A shorter water injection delay time causes a smaller residual wall thickness but results in more fingering [19] [23]. The water volume flow rate is an important parameter on fingering, double wall and the residual wall thickness. A higher water volume flow rate gives a smaller residual wall thickness but more fingering and double wall [21]. The melt temperature has an influence on fingering and the residual wall thickness. Increasing the melt temperature leads to a smaller residual wall thickness but to more fingering [19] [20] [23]. Further experiments in this research focuses on the influence of the water injection delay time, the water volume flow rate and the melt temperature on the residual wall thickness and the occurrence of part defects for PA6, using a design of experiments. 2. Experimental procedure 2. 1 Materials To investigate the residual wall thickness and part defects like water inclusions, fingering and double wall of water assisted injection moulded products, two polyamides (PA F223-D and PA F130-E1 from DSM) and a polypropylene (PP 400-GA05 from Ineos) were used. The melting and crystallization temperature of the materials were measured with differential scanning calorimetry (TA Instruments 2920 CE). The viscosity was measured with a capillary rheometer (CEAST Smart Rheo 2000 twin bore). The complex viscosity, storage and loss modulus were measured with a parallel plates rheometer (AERES strain controlled rheometer). The measurements show that the zero-shear viscosity of the polypropylene is higher than those of the polyamides. PA F223-D has a higher zero-shear viscosity than PA F130-E1. This indicates that the molecular weight is higher for polypropylene than for PA F223-D and that PA F130-E1 has the lowest molecular weight. The decrease in viscosity at higher shear rates occurs at lower frequencies for polypropylene in comparison with the polyamides. This indicates a higher molecular weight distribution for polypropylene than polyamide. PA F223-D has a higher molecular weight distribution than PA F130-E1. . 2 Moulded parts The part that is moulded for this experiment is displayed in figure 1. It contains four curved sections varying in radius of curvature. The polymer and water enter the cavity at the bottom side. Water enters when a movable injector is pushed forward and a core at the end of the part is pulled allowing the polymer to be removed out of the inner core of the part. Figure 1: moul ded part containing four curved sections 2. 3 Equipment The injection moulding was executed with an Engel 80-ton injection moulding machine ES 330H/80V/80HL-2F. The dimensions of the machine are 4,80 m x 2,22m x 2m. The single screw diameter is 50 mm and the plastification unit can operate with a maximum injection rate of 152 cm? /s. A volume flow rate controlled water injection unit brings the water into the mould. It can operate with a maximum water volume flow rate of 30 l/min, delivered by a maximum pressure of 200 bar. During the tests a maximum pressure of 160 bar was applied. Three pressure sensors type Priamus are localized in the mould. An IR-camera type FLIR is used to observe the temperature distribution over the produced handles after moulding. The IR-images were used to compare with the internal section to discover the cause of part defects, because water in the product gives lower temperatures on the IR-image. The dried hollow polymer handles are sawed in lengthwise direction with a band saw. The band saw is type Metabo bas 260 swift. After sawing the hollow polymer handles, the internal section were scanned with a scanner type Cannon FG17500. A metric software 8. 01 plus was applied to analyze the surface quality of the polymer. With the aid of the software, the surface area of the wall and the part defects can be determined. . 4 Method DOE procedure The experiment investigated four processing parameters that were selected after a preliminary literature study, assuming these will have a significant influence on the residual wall thickness and part defects. These parameters are the water volume flow rate, water injection delay time and melt temperature. Using the design of experiments approach, each parameter was measured on a low and high setting; making this a 23 experiment. In addition three centre points were measured bringing the total number of experiments to 11 for each material. Response functions were constructed for residual wall thickness, weight and defects. The significance of each parameter was checked by comparing its effect to the deviation of the centre points, neglecting the parameter if its effect is smaller than the centre point deviation. Experimental procedure After steady state was reached, five shots were produced for each setting of water volume flow rate, water injection delay time, melt temperature. For each last shot of an experiment, a print screen of the pressure evolution and an IR-image was taken. During the process the following parameters were measured: * real injection time; * absolute shot volume; * real cushion; * flow number. After moulding, the parts were dried with compressed air to remove water of the inner- and outer surface of the product. Then the injection side of the product was removed and both halves were weighed. The sawed injection product was controlled on the presence of defects giving a first indication of the quality of the product. Afterwards the handle was dried in a furnace for 44 hours on 90  °C. After drying, the handles were weighed again obtaining the weight of the water inclusions in the product wall. Three representative handles were sawed in lengthwise direction and the breams were removed. The handles were scanned to determine the residual wall thickness and the percentages of defects like water inclusions, fingering and double wall. Table 1: Processing variables and settings used for the experiments | A| B| C| Process parameters| Water volume flow rate (l/min)| Water injection delay time (s)| Melt temperature ( °C)| -1| 10| 1,5| 240| 0| 20| 5| 260| 1| 30| 8,5| 280| A| B| C| Experiment| Water volume flow rate (l/min)| Water injection delay time (s)| Melt temperature ( °C)| 1| 20| 5| 260| 2| 10| 1,5| 240| 3| 30| 8,5| 240| 4| 30| 1,5| 240| 5| 10| 8,5| 240| 6| 20| 5| 260| 7| 30| 8,5| 280| 8| 10| 1,5| 280| 9| 10| 8,5| 280| 10| 30| 1,5| 280| 11| 20| 5| 260| Table 2:Experiment schedule for parameter settings The part defects are calculated as follows: The parameters whic h have an influence on the product quality are the water volume flow rate, the water injection delay time and the melt temperature. The tested parameter settings are presented in table 1. A code using -1 for low, 0 for center point and 1 for high setting is applied. The combination of parameter settings (Table 2) are determined using design of experiments. Using the design of experiments method makes is possible to obtain a better understanding of the formation of the defects and the influence of the processing parameters. Eventually a moulding window will e determined in which the defects are minimized. 2 Results and discussion 3. 1 Effect of water volume flow rate Figure 2 shows the effect of the water volume flow rate on the residual wall thickness and the product defects. Following paragraphs discuss these diagrams. Influence on the residual wall thickness and product weight Considering the residual wall thickness, polypropylene has a smaller residual wall thickness than the residual wall thickness of polyamide for all experiments. Polypropylene has a higher molecular mass, causing a wider water flow front. The higher molecular weight distribution (MWD) of PP causes a block velocity profile of the water resulting in a higher velocity on the polymer- water interface. The higher velocity causes a higher shearing and consequently a lower viscosity, resulting in a higher removal. This results both in a smaller residual wall thickness and a lower part weight. The density of polypropylene is lower compared to compared to the density of polyamide, which is also an explanation for the lower weight of product. Regarding the product weight and the residual wall thickness, the two polyamides do not differ much and correspond to each other. This is probably due to the small difference in molecular mass and molecular weight distribution. Figure 2: Effects of water volume flow rate on water inclusions, residual wall thickness, fingering and double wall The residual wall thickness of polyamide seems not to be significantly affected by the water volume flow rate. Polypropylene however, tends to increase in residual wall thickness by application of a lower water volume flow rate. These results correspond to the suggestion that a higher water volume flow rate gives a smaller residual wall thickness, as was found in preliminary literature study. In general a material with a high MWD, like PP, will be more influenced by the flow rate than other materials like polyamides. Influence on water inclusions In general the water inclusions tend to decline when the water flow rate increases. A higher flow rate provides more shearing, giving a lower viscosity. The water can easily remove the internal polymer and does not penetrate into the walls of the polymer. PP completely corresponds to this theory, but the polyamides show an irregularity during high flow rates. this can be explained by the strong variations in injection time and a chance in the water flow profile to a profile called recirculation flow. It pushes the water into the walls causing an increase in water inclusions. The strong variations that occur with PP are probably caused by its high MWD. This property also played an important role regarding the RWT. Influence on fingering Fingering is probably caused by differential shrinkage, making a material with a high degree of crystallization like polypropylene vulnerable to this defect. The defect diminishes at high flow rates where the wall thickness is smaller, making it more difficult for polypropylene to shrink and for fingering to occur. PA F130-E1 exhibits a low variation in fingering in comparison to the other materials. This material is not in its area of shear tinning when working with low flow rates, resulting in a constant viscosity and residual wall thickness. Because of this low variation in RWT and corresponding shrinkage with changing flow rate the effect of the flow rate will be very small. In general materials with a high MWD and MM like PP show more fingering than materials with low MWD and MM like PA F130E1. PA F223D will take a intermediate position taking into account that its centre point is not completely representative. This trend for fingering is visible for all parameters. Influence on double wall The influence of the flow rate shows an overall optimum profile. Low and high flow rates cause more double wall than an intermediate setting. A first theory relates this effect to the pressure inside the part. Low flow rates exert low pressure on the polymer melt and the polymer will not form a rigid layer, making it possible for the water to penetrate into the polymer walls. High flow rates cause high pressures inside the part forcing the water into the walls. The second theory is based on the tendency of water to follow the ath of least resistance and can only explain the effect with low flow rates. The low rate will cause almost no shear stress inside the polymer so it will not reach the shear tinning area. The polymer will not easily be pushed back by the water and the water will penetrate the walls where the resistance is much lower. The effect of the water volume flow rate on double wall is the same as for water inclusions, which is explained by the rel ation between water inclusions and double wall. Water inclusions can grow during the water hold time, collapsing into double walls in the product after pressure removal. The higher double wall defects for PAF130-E1 in comparison to PA F223-D are probably caused by the difference in molecular mass. PA F130-E1 has a lower molecular mass and thus a less viscous melt resulting in a more easily penetrable material. Another noticeable result is that of the investigated materials, PA F223-D shows high part defects but relatively the smallest double wall defects. PP, the material with the highest MM shows more double wall at high flow rates for which no explanation can be found. 3. 2 Effect of the water injection delay time Figure 3 shows the effect of the water injection delay time on the residual wall thickness and the product defects. Following paragraphs discuss these diagrams. Influence on the residual wall thickness and product weight A shorter water injection delay time causes a decline in the residual wall thickness and weight of product for polyamide and polypropylene, as was predicted by literature. When the water injection delay time is short, the polymer is still hot and has a low viscosity, giving the water the opportunity to hollow out the polymer more. A higher water injection delay time causes a higher residual wall thickness and weight of product because the melt viscosity increases. The residual wall thickness is higher for polyamide than for polypropylene, for the same reasons as discussed under the previous paragraph. Influence on water inclusions An increase in delay time is accompanied by an increase in viscosity that makes it more difficult for the water to penetrate into the walls. However, if the viscosity is too high, the water can also be forced into the walls, which explains the slight increase in water inclusions for PP 400-GA05 and PA F130-E1. Figure 3: Effects of the water injection delay time on water inclusions, residual wall thickness, fingering and double wall The strong decrease in water inclusions that occurs with polypropylene is caused by the high heat capacity of this material making it cool down faster than the polyamides and increasing its viscosity faster. PA F130-E1 shows less defects in comparison with PA F223-D, probably caused by its strong temperature related viscosity. During the delay time the viscosity strongly increases, making it more difficult for the water to penetrate. Influence on fingering Increasing the delay time increases the residual wall thickness and should result in a higher chance of fingering. In general this trend can be observed from the diagrams. More fingering occurs within PP 400 GA05 caused by its higher degree of crystallization. Furthermore, this polymer is processed at much higher temperatures than its melting point, leading to further shrinkage and corresponding fingering. The presence of defects during processing with long delay times is caused by a greater residual wall thickness, which leads to more differential shrinkage. Processing with short delay times increases the presence even further, but no plausible statement can explain this. Therefore further research will be necessary. The results for the centre point of PA F223-D are probably not representative, since it is based on a single experiment of three shots. Influence on double wall The water injection delay time shows an overall optimum profile, which can be related to the shift of the rigidity in time, caused by the temperature drop over time. Production with a short delay time will push water inside the low viscosity polymer which makes it easy for the water to penetrate. Increasing the delay time also increases the viscosity and thus the rigidity of the polymer making it harder to penetrate the walls. However, if the viscosity is too high, the water will also be forced into the walls. PA F130-E1 shows more double wall because its viscosity is highly temperature related. Longer delay times will lead to larger temperature drops and a corresponding increase in viscosity. 3. 3 Effect of the melt temperature Figure 4 shows the effect of the melt temperature on the residual wall thickness and the product defects. Following paragraphs discuss these diagrams. Influence on the residual wall thickness and weight of product Considering the residual wall thickness, polypropylene has a lower residual wall thickness and weight of product compared with polyamide for all experiments. This might be due to the higher molecular weight and the higher molecular weight distribution of polypropylene. The higher molecular weight distribution shows a square blocked velocity profile causing a higher velocity on the wall and a higher shearing. This results in a lower viscosity and therefore more removal of the polymer decreasing the residual wall thickness and weight of product. PA F130-E1 and PA F223-D are quite similar and do not differ much in residual wall thickness and weight of product. Increasing the melt temperature leads to a smaller residual wall thickness as was suggested by literature, because a higher melt temperature makes the polymer less viscous so more polymer can be removed by the water. The residual wall thickness of PP decreases from 240 °C to 260 °C but increases to 280 °C. The increase of the melt temperature is difficult to explain and is possible a unreliable point. In fact, also for polypropylene a decreasing tendency is remarkable. Influence on water inclusions There is a trend towards higher water inclusions when a higher melt temperature is applied. This parameter thus shows the opposite effect of the delay time. PA F130-E1 differs from the other materials, probably due to the strong variations in injection time during production. Furthermore this polymer shows a lot of internal heating (viscous heating) when Figure 4: Effects of the melt temperature time on water inclusions, residual wall thickness, fingering and double wall high pressure is exerted, leading to a drop in viscosity. This effect usually appears in combination with low melt temperatures where the polymer has a lot of pressure to bear. So low temperatures will lead to viscous heating and therefore to high intern temperatures. The water can then easily enter the walls of the polymer due to the lower vicosity. Influence on fingering When processing the material at low temperatures, the material will have to shrink less and thus less fingering will occur. This trend is clearly visible for the polyamides, taken into account that the centre point of PA F223-D is not representative. In fact, the effects should show an opposite effect from the delay time, but this is not clearly noticeable. Further research will be necessary to explain these irregularities. Influence on double wall A higher melt temperature causes an overall increase in double wall defects for all three materials. This effect is related to the viscosity of the polymer which varies with temperature. High temperatures will lead to a decrease in viscosity making the polymer more penetrable for water. Another theory is based on the water flow profile inside the polymer. Higher temperatures usually correspond to smaller residual wall thicknesses changing the flow profile into a recirculation flow where water will be pulled into the walls. 3. 4 Comparison results of response functions and graphical tendencies Table 3 gives an overview of the best parameter settings to reduce each part defect and the total defects for each material, comparing the results of a response function (before /) and the graphics in figure 1/2/3 (after /). The response functions were constructed using the design of experiments method. Regarding the defects, only one response function was made which ncludes both fingering and double wall. Ideal settings according to response functions Using the response functions several conclusions can be made for the ideal settings of the parameters. A high water injection delay time creates less water inclusions in both polyamides. In addition, the polyamides show the same optimal settings of all parameters for the residual wall thickness. A low water volume flow rate is beneficial for the reduction of the residual wall thickness, fingering and double wall. Other settings conflict to give minimal part defects in polyamide. In general, PA F223-D has minimal part defects for a low water volume flow rate, a high water injection delay time, and a low melt temperature. PA F130-E1 requires a low water volume flow rate as well, but a low water injection delay time and a high melt temperature. The optimal settings for the minimal percentage water inclusions, fingering and double wall are highly contradictory for polyamide and polypropylene. PP 400-GA05 requires a high water volume flow rate for a smaller residual wall thickness but the other parameters have the same optimal settings for the residual wall thickness as polyamide 6. The water volume flow rate and the water injection delay time do not influence fingering and double wall significantly, so no conclusions can be made for these settings to obtain minimal fingering and double wall. If also the water inclusions and the residual wall thickness are taken into account, PP400-GA05 shows minimal part defects for a high water volume flow rate, a low water injection delay time and a low melt temperature. There can be concluded that for all three materials the best parameter settings for residual wall thickness, fingering and double wall are not the same. Since other effects may probably have an influence on the materials, further investigation will be necessary. Ideal settings according to previous diagrams The following best parameter setting are based on the previous graphics. Regarding the residual wall thickness, the best parameters for PP and PA F130D are an intermediate water flow rate, a low water injection delay time and a high melt temperature. For PA 223D, a low water flow rate is required and the other parameters are the same. For fingering, a high water volume rate, an intermediate water injection delay time and melt temperature give the best results for PP. PA F223D gives the best results for a low water volume flow rate and water injection delay time and an intermediate melt temperature. PA F130E1 in contrary, the best parameters setting are a high water volume flow rate and a low water injection delay time and melt temperature. The parameters setting are different for the three materials and show a lot of irregularities. Considering double wall, the best parameter settings are a low water flow rate, water injection delay time and melt temperature. For both polyamides the best parameter setting are equal, an intermediate water flow rate, delay time and melt temperature. For the water inclusions, the best results were observed for a high water volume rate and an intermediate water delay time and melt temperature. PA F223D shows less water inclusions when an intermediate flow rate, a low delay time and in intermediate melt temperature is used. PA F130E1 in contrary gives the best results for a intermediate flow rate and delay time and a low melt temperature. Ideal settings for PA F223-D| | Optimal setting| Response factor| Target figure| Water volume flow rate| Water injection delay time| Melt temperature| Water inclusions| Low| High/High| High/High| Low/Low| Residual wall thickness| Low| Low/High| Low/Low| High/High| Fingering and double wall| Low| Low/High| High/Low| Low/Low| Total| | Low/High| High/Low| Low/Low| Table 3: Overview of ideal settings for the materials for each part defect Ideal settings for PA F130-E1| | Optimal setting| Response factor| Target figure| Water volume flow rate| Water injection delay time| Melt temperature| Water inclusions| Low| Low/High| High/High| High/Low| Residual wall thickness| Low| Low/High| Low/Low| High/High| Fingering and double wall| Low| Low/High| Low/Low| Low/Low| Total| | Low/High| Low/Low| High/Low| Ideal settings for PP 400-GA05| | Optimal setting| Response factor| Target figure| Water volume flow rate| Water injection delay time| Melt temperature| Water inclusions| Low| High/High| Low/High| High/Low| Residual wall thickness| Low| High/High| Low/Low| Low/High| Fingering and double wall| Low| -/High| -/Low| Low/Low| Total| | High/High| Low/Low| Low/Low| Once again, here can be concluded that the best parameter settings for residual wall thickness, fingering and double wall are not the same. Since other effects may probably have an influence on the materials, further investigation is necessary. . 5 Detection of part defects 3. 5. 1 IR-images IR images were tested if they can be used to obtain an indication of the quality of the product. This could be an important tool during production as it can deliver information about the internal structure without damaging the part. It was found that a uniform heat distribution in the part usually corresponds to few defects in the walls. The polymer equally shrinks and cools, causing no stress in the walls which could lead to defects. Figure 5 shows the section and an infrared image of a hollow part from PP 400-GA05 without defects. The corresponding IR picture shows no significant Figure 6: Scan and IR image of PP 400-GA05 product with defects irregularities in the heat distribution. The areas where the part has a higher or lower Figure 5: Scan and IR image of PP 400-GA05 product without defects temperature than the bulk are caused by respectively larger and smaller residual wall thicknesses. Small defects like fingering can occur where colder areas are completely surrounded by larger hot material making it isolated cold regions. If the cold area is gradually spread throughout the part and is therefore no isolated region, fingering is often not present. The isolated colder regions are most likely filled with water which provides more efficient cooling than the rest of the part, resulting in uneven shrinkage and corresponding fingering cavities. Large defects like double wall are often present where a relative large cold area spreads throughout the complete section and is surrounded by hot material. These defects are also likely to occur in regions with higher temperature than the rest of the part. However, the latter can also correspond with a larger residual wall thickness and is thus not conclusive for the presence of double wall defects. Figure 6 shows a part with double wall defects and the corresponding infrared image where the isolated hot (white) and cold areas (yellow) are indicated. The texture of the internal surface can not be judged with an infrared image. PA F130-E1 tends to show a rougher surface in regions with a much lower temperature, but not all parts share this conclusion. Within the other materials a rough surface does not corresponds with lower temperature areas thus the infrared does not delivers clear information about this property. 3. 5. 2 Pressure and injection rate profiles The pressure profiles and the injection rate during the injection of the melt can be used to declare some of the defects shown in the different polymer samples. The injection rate was set on 45 mm/sec and the maximum feasible pressure of the WAIM equipment was 160 bar. For the polyamides, this maximum pressure was exceeded in some cases during filling of the mould. This caused a temporary reduction of the injection rate and possibly some of the part defects of polyamide. Polypropylene does not show this trend because it has a lower flow number than PA. Figure 7 shows an example of this phenomenon in PA F223-D. In general it can be concluded that when the temperature increases the measured pressure and the flow number decrease. This reduction in pressure can be explained by the fact that the viscosity of the material will be lower at a higher temperature, so the polymer can flow easier and less pressure has to be applied. However it is not guaranteed that an irregularity in the injection profile of the polymer results in problems during water injection. This experiment was to limited to make clear conclusions about this effect. Figure 7: Pressure and injection rate profile for PA F223-D (green=pressure, blue=injection rate) 4. Conclusions 4. 1 General This report has studied the influence of melt and processing parameters on the residual wall thickness and the occurrence of part defects of PA6 parts produced with water assisted injection moulding. The study examined two polyamides (PA F223D, PA F130E1) and polypropylene 400 GA05 that was used as a reference material. According to a design of experiments, the water volume flow rate, the water injection delay time and the melt temperature are the investigated processing parameters. The water volume flow rate settings are 10, 20 and 30 l/min, the injection delay time settings are 1,5s, 5s and 8,5s and the melt temperature settings are 240 °C, 260 °C and 280 °C. It was found that the residual wall thickness showed a large distribution for all three materials, even for shots from a single experiment and therefore an extra analysis was made on the weight of the products. The product weight can give an indication for the wall thickness as a low weight usually corresponds to small thicknesses. Based on this theory it was found that the water volume flow rate has little influence on the weight and wall thickness. A larger delay time increases the viscosity of the polymer and leads to higher weight and a larger wall thickness. The melt temperature has the opposite effect, decreasing the viscosity at higher temperatures and therefore decreasing the wall thickness and weight. PP has a lower weight comparing with the two polyamides. This can be explained that PP has a higher molecular weight and molecular weight distribution. A higher molecular weight gives a parabolic velocity profile and a higher molecular weight distribution shows a square blocked velocity profile causing a higher velocity located on the wall. The higher velocity causes a higher shearing giving a lower viscosity. This results in more removal of the polymer and the residual wall thickness decreases. In fact, a lower residual wall thickness exhibits a lower weight of product. The water inclusions for the three materials tend to decline when the water flow rate increases although PP shows some irregularities. The delay time has an overall optimum profile. Intermediate settings exhibit less inclusions in comparison to other settings. The melt temperature has the opposite effect of the delay time so more water inclusions occur when higher temperatures are applied. Other defects like fingering and double wall are also influenced by the investigated processing parameters. The water flow rate shows an optimum profile for double wall, so an intermediate setting will yield the best results. For fingering the three materials all act in a different way to the flow rate. An optimum profile also occurs for double wall when the delay time is investigated. In general, fingering increases when the delay time increases, but the materials show a lot of irregularities. An increase in melt temperature causes an overall increase of fingering and double wall. Comparing PA6 and PP, PP shows an overall smaller residual wall thickness than PA6, but on average the same percentage of part defects. This means that a reduction in residual wall thickness does not influence the product quality for part defects positively. When comparing the different polyamides 6, the investigated low viscosity polyamide 6 PA F223-D show less water inclusions and fingering but more double wall than the medium viscosity polyamide 6 PA F130-D. The best choice for a polyamide depends on the relative importance of the negative influence of each part defect on the product quality. This is discussed in detail in the next paragraph. To get an indication of the quality of the product IR images can be used. It was found that a uniform heat distribution corresponds to few defects and irregularities point to the presence of defects like fingering or double wall. The internal texture of the surface can not be examined with IR. This study concludes that the investigated parameters have a significant influence on the presence of part defects and on the residual wall thickness. However, there are still irregularities in the results of the fingering phenomenon that can not be explained yet with the current knowledge of the water assisted injection moulding process. Therefore further analysis will be necessary to examine this part defect. Further research can be done by expanding the design of experiments and by producing more shots for each experiment. Producing more than three shots of each experiment should give more corresponding results, because the standard deviation of three shots is usually high. 4. 2 Selection of the material for WAIM Three materials were used in this experiment namely PA F223D, PA F130E1 and PP as reference. The residual wall thickness, weight of product, water inclusions and part defects like fingering and double wall must be compared with each other to choose the best material. This by varying the selected parameters like water volume rate, water injection delay time and melt temperature. PP has in general the lowest weight of product and residual wall thickness for the three investigated parameters: water volume rate, water injection delay time and melt temperature. As a result of a smaller residual wall thickness, PP has the lowest weight of product. Considering the water inclusions a decreasing tendency is obtained when a higher water volume flow rate and water injection delay time is used. There is a trend toward higher water inclusions when higher melt temperature are applied. Regarding to fingering and double wall, an opposite effect is noticeable. Increasing the water volume rate and water injection delay time gives a decreasing fingering tendency but more double wall effects. For a higher melt temperature, an increase of fingering and double wall is observed. PA F130E1 and PA F223D are quiet similar to each other in weight of product and residual wall thickness. For the weight of product PA F130E1 and PA F223D correspond to each other and for the residual wall thickness they do not differ much for all three investigated parameters. Regarding the water inclusions, both polyamides decline when water the flow rate increases. The highest flow rate provides more shearing and therefore a lower viscosity resulting in more water inclusions. Increasing the water injection delay time leads to lower water inclusions because the viscosity increases which makes it more difficult for water to penetrate into the walls. When higher melt temperatures are applied, results in a trend towards higher water inclusions because of the lower viscosity. In general, PA F223D shows more water inclusions comparing with PA F130E1 for the water volume flow rate, water injection delay time and the melt temperature. Considering fingering and double wall, different results were observed for the two polyamides. In general it is remarkable that PA F223D shows more fingering then PA F130E1 while PA F130E1 gives more double wall then PA F223D and this for the three investigated parameters. For the water volume flow rate, the polyamides act in different ways towards fingering. Although, for double wall the flow rate shows an optimum for the polyamides so an intermediate setting gives the best results. When the water injection delay time increases there is also an increasing tendency of fingering observed but the materials show a lot of irregularities. Increasing the melt temperature gives an increase of fingering and double wall as well. In this investigation can be concluded that both polyamides have their advantages and disadvantages. A selection of the best polyamide depends on which effect is undesirable. The residual wall thickness are the same for the two polyamides. PA F223D shows more water inclusions and fingering for all investigated parameters. However, PA F223D shows less double wall and therefore the best results. PA F130E1 in contrary gives more double wall effects but less fingering and water inclusions. In fact, PA F223D is preferred when double wall must be reduced and PA F130E1 is preferred when fingering and water inclusions must be reduced. Further investigation is necessary on another type of polyamide which improves the product quality using WAIM. References [1] Knights, M. (2002). Water Injection Molding Makes Hollow Parts Faster, Lighter. Plastics Technology, pp. 42-47, 62-63. 2] Liu, S. -J. , & Lin, M. -J. , & Wu, Y. -C. (2007). An experimental study of the water-assisted injection molding of glass fiber filled poly- butylene-terephthalate (PBT) composites. Composites Science and Technology, pp. 1415- 1424. [3] Liu, S. -J. , & Hsieh, M. -H. (2007). Residual Wall Thickness Distribution at the Transition and Curve Sections of Wat er-assisted Injection Molded Tubes. International Polymer Processing, pp. 82-89. [4] Liu, S. -J. , & Chen, Y. -S. (2003). Water- Assisted Injection Molding of Thermoplastic Materials: Effects of Processing Parameters. Polymer Engineering and Science, pp. 806- 1817. [5] Liu, S. -J. , & Wu, Y. -C. (2007). Dynamic visualization of cavity-filling process in fluid- assisted injection molding-gas versus water. Polymer Testing, pp. 232-242. [6] Liu, S. -J. (2009). Water Assisted Injection Molding: A Review. International Polymer Processing, pp. 315-325. [7] Liu, S. -J. , & Chen, Y. -S. (2004). The manufacturing of thermoplastic composite parts by water-assisted injection-molding technology. Composites Part A: Applied Science and Manufacturing, pp. 171-180. [8] Chavarria, F. , & Paul, D. R. (2004). Comparison of nanocomposites based on nylon 6 and nylon 66. Polymer 45, pp. 8501-8515. [9] Li, D. , Liu, Q. , Yu, L. , Li, X. , & Zhang, Z. (2009). Correlation between interfacial interaction and mechanical properties of PA-6 doped with surface-capped nano-silica. Applied Surface Science 255 pp. 7871-7877. [10] Sannen, S. (2010). Polyamides. Intern presentation of Catholic University Leuven. [11] Su, K. , Lin, J. , & Lin, C. (2007). Influence of Reprocessing on the Mechanical Properties and Structure of Polyamide 6. Journal of Materials Processing Technology, pp. 532-538 [12] Fornes, T. , Yoon, P. , Keskkula, H. , & Paul, D. (2001). Nylon 6 nanocomposites: the effect of atrix molecular weight. Polymer, pp. 9923- 940. [13] Uribe-Arocha, P. , Mehler, C. , Puskas, J. E. & Alstadt, V. (2003). Effect of Sample Thickness on the Mechanical Properties of Injection Molded Polyamide-6 and Polyamide- 6 Clay Nanocomposites. Polymer 44, pp. 2441-2446. [14] Steeman, P. & Nijenhuis, A. (2010). The Effect of Random Branching on the Balance between Flow and M echanical Properties of Polyamide-6. Polymer 51, pp. 2700-2707. [15] Incarnato, L. , Scarfato, P. , Scatteia, L. & Acierno, D. (2004). Rheological Behavior of New Melt Compounded Copolyamide Nanocomposites. Polymer 45, pp. 3487-3496. 16] Meng, Y. Z. & Tjong, S. C. (1996). Rheology and morphology of compatibilized polyamide 6 blends containing liquid crystalline copolyesters. Polymer 39 No. 1, pp. 99-107. [17] Acierna, S. , & Van Puyvelde, P. (2005). Rheological Behavior of Polyamide 11 with Varying initial Moisture Content. Journal of Applied Polymer Science, pp. 666-670. [18] Chow, W. , Bakar, A. , & Ishak, Z. (2005). Water Absorption and Hygrothermal Aging Study on Organomontmirillonite Reinforced Polyamide6/polypropylene Nanocomposites. Journal of Applied Polymer Science, pp. 780- 790. [19] Liu, S. -J. , & Lin, S. -P. (2005,april). Study of Fingering’ in Water-assisted Injection Molded Composites. Polymer Rheology and Processing lab. [20] Lin, K. -Y. , & Liu, S. -J. (2009) . The Influence of Processing Parameters on Fingering Formation in Fluid Assisted Injection Molded Disks. Polymer Engineering and Science, pp. 2257-2263. [21] Walter Michaeli, E. H. (2010). ‘Perspective Kunststofftechnik berichte 2010’ IKV- Kolloquium Aachen 2010 pp. 19-21 (Analyse der Fehlerentstehungs-mechanismen). [22] Michaeli, W. , & Lettowsky, C. , & Groenlund, O. (2005). Understanding Residual Wall Thickness. Kunststoffeplast Europe 95, pp. 87-91. [23] Huang, H-X. , & Zhou, R-H. 2009). Preliminary investigation on morphology in water-assisted injection molded polymer blends. Polymer testing, pp. 235-244 [24] Liu, S. -J. , & Wu, Y. -C. (2006). A Novel High Flow Rate Pin for Water-assisted Injection Molding of Plastic Parts with a More Uniform Residual Wall Thickness Distribution. International Polymer Processing, pp. 436-439. [25] Lin, K. -Y. , Chang, F. -A. & Liu, S. -J. (2009). Using Differential Mold Temperatures to improve the Residual Wall Thickness Uniformit y Around Curved Sections of Fluid Assisted Injection Molded Tubes. International Communications in Heat and Mass Transfer 36, pp. 491-497.

Apple a Day Keeps a Doctor Away

Pet a Day Keep the Doctor Away! INTRODUCTION: A. Attention-Getter: They say that an apple a day keeps the doctor away, but how much better would you feel if the apple was being presented to you by a cute dog or cat? B. Tie to the audience in this persuasive speech topics outline: If someone that you care about is dealing with encroaching old age, spending some time with an undemanding, loving animal can be something that is important for you in more ways than one. C. Personal experience: For example, my granddad was in dire straits after my granny died.After thirtyfive years together, he didn't know what to do with himself until he ended up adopting an older Labrador Retriever. The change was immense, and suddenly we had a familyman who was interested in the world around him and reaching out again. The change was amazing! D. Thesis Sentence of this persuasive speech topics outline: Pets make an impressive positive change in the mental and physical health, and if you are concerned wit h the issue personally, consider the health benefit potentials for a beloved older person in your life. E.Preview of the main points of this persuasive speech topics outline: First, I will discuss the ways an animal is capable of making an elder person feel connected to the world at large. Then, I will show how the company of a loving cat or a dog makes the difference in a person's mental and physical outlook. And then, I'll tell you what to keep in mind when you are considering what pet might be appropriate for someone in your family. Transition sentence of persuasive speech topics outline: As people get older, there is very much a concern of not being needed.BODY OF THE PERSUASIVE SPEECH TOPICS OUTLINE MAIN POINT I: A human-companion animal is capable of making the elderly feel connected to the world at large. 1. Elderly people who have had their adult children leave home and who have lost spouses often find that it is difficult to connect with other people and because of this, th ey end up feeling a great deal more introverted and isolated. 2. Pets can make a huge difference when it comes to how well they cope with change and how they react to the world. An animal will depend on them, and give them that essential feeling of being needed again. . Elderly people also often find that they are living their lives without much tactile contact. Spouses might have passed on, and they might not be comfortable looking for tactile comfort from the people around them. This is where dogs and cats come in. 4. Cats and dogs love physical contact, and because of this, they are willing to go seeking it. A cat may love to sit in your lap or to sit down next to you for petting or you may find that a dog loves to roll around with and sit leaned up next to your legs†¦Transition sentence of this persuasive speech topics outline: Elderly people often develop feelings of being unloved or lonely; an animal who is concerned with them and who loves them can make a huge difference in the way that they feel. MAIN POINT II: Pets can help improving their mental health; animals seem wonderfully intuitive when it comes to responding to how their humans feel. 1. A cat or a dog, especially one that is closely bonded to you, can feel in tune with your emotions. If you have ever been upset and had an animal come to cuddle you or to check on you, you know how soothing this can be.Rhetorical persuasive speech topics outline questions: o Have you ever felt more relaxed when a cat walks up and demands to be petted? o Have you ever not been able to resist a smile when a dog comes up and wants to play? These feelings are not merely happening in isolation. 2. There are plenty of scientific studies that show us that having pets around can lower the blood pressure and help us relax. When you think about how many elderly people are often beset by feelings of stress and how this can lead to things like heart disease or impaired functioning: looking into how pets can help is ess ential! . Pets are company that is very low stress and the truth is that when you give them what they need, they reciprocate with a great deal of love and joy! At the most basic level, pets can be very non demanding company. When you mess up, they are willing to forgive you, and they do not ask for much. They need food, attention and care, but they are not going to ask for things that you cannot give them. Transition sentence of this persuasive speech topics outline: If you're interested in making sure that a beloved older person stays active and social, it is time to take a look and see what a pet can do.

Causes of Separation of East and West Pakistan

The separation of East Pakistan was a great setback to Pakistan. By 1970, sentiments for national unity had weakened in East Pakistan to the extent that constant conflict between the two Wings dramatically erupted into mass civil disorder. This tragically resulted in the brutal and violent amputation of Pakistan’s Eastern Wing. The Bangladesh Liberation War was a South Asian war of independence in 1971 which established the sovereign nation of Bangladesh.The war pitted East Pakistan and India against West Pakistan, and lasted over a duration of nine months. Popular attention has, thus far, focused on the Pakistani army‘s action against the Bengalis, or on the India-Pakistan war. However, East Pakistan in 1971 was simultaneously a battleground for many different kinds of violent conflict that included militant rebellion, mob violence, military crackdown on a civilian population, urban terrorism to full-scale war between India and Pakistan. It witnessed large-scale atrocit ies, the exodus of 10 million refugees and the displacement of 30 million people.Begali nationalists declared independence (March 26, 1971). The Pakistani Army attempted to regain control in East Pakistan and committed terrible atrocities. Indian troops entered the war and quickly defeated the Pakistani Army. The Pakistanis conceded defeat (December 16, 1971). President Yahya Khan resIgned. Zulfikar Ali Bhutto took over Pakistan and recognized Bangladesh as an independent country.Causes which led to the civil war 1971Geographically Divided Nation  Tensions between East and West Pakistan existed from the creation of Pakistan (1947). Pakistan was an odd creation wIth the two parts, East and West Pakistan separated by more than 1,000 miles. The two parts of Pakistan shared few cultural and social traditions other than Islam.The fusion of east and west on the basis of Islam led to the frustration of Bengali nationalism. The lack of common bonds was accentuated when political figures i n the West seized control of the new state, dominating both political and economic power. The military governments which gave little attention to political demands in East Pakistan only promoted discord. As a result, the resentment in East Pakistan gradually grew.Awami LeagueThe Awami League was founded as a an opposition party in East Pakistan soon after Pakistani independence (1949). The League has a moderately socialist ideology as was widespread in the new independent countries emerging from European colonial empires. Cofounder Sheikh Mujibur Rahman assumed leadership a few years later (1953). Disturbed by the dominate role of West Pakistan leasers, Rahman demanded a more equitable distribution of power (1966). His plan called for a federation of East and West Pakistan which would have given EastPakistan a level of autonomy.Elections 1970The first democratic elections in Pakistan were held in 1970 with the Awami League winning with a substantial majority. However Yahya Khan bann ed the Awami League and declared martial law after talks on sharing power failed. Bhutto was famously heard saying â€Å"break the legs† if any member of People's Party attend the inaugural session at the National Assembly. Fearing on capitalization on West Pakistan, West-Pakistanis fears of East Pakistani separatist, and Bhutto demanded to form a coalition with Mujib.Both Mujib and Bhutto were agreed upon the coalition government, with Bhutto as President and Mujib as Prime minister. The Military government and General Yahya Khan was kept unaware of such of these developments. Both Bhutto and Mujib continued a political pressure on Khan's military government. Pressured by his own military government, General Yahya Khan postponed the inaugural session, and ordered to arrest Mujib and put Bhutto on house arrest.Bengali Language MovementIn 1948, the Government of the Dominion of Pakistan ordained Urdu as the sole national language, sparking extensive protests among the Bengali- speaking majority of East Bengal. Facing rising sectarian tensions and mass discontent with the new law, the government outlawed public meetings and rallies. The students of the University of Dhaka and other political activists defied the law and organised a protest on 21st February 1952.The movement reached its climax when police killed student demonstrators on that day. The deaths provoked widespread civil unrest led by the Awami Muslim League, later renamed the Awami League. After years of conflict, the central government relented and granted official status to the Bengali language in 1956, which was too late to diminish the the hatefulness East Pakistanis had for Urdu speakers.Non Bengali MuslimsNon-Bengali Muslims from the north Indian states of Uttar Pradesh and Bihar who had migrated to East Pakistan (East Bengal) after the partition of India were collectively referred to as â€Å"Biharis† by the Bengalis. Pro-liberation Bengalis assumed these non-Bengalis to be in fav our of united Pakistan. But a significant minority of Bengalis, including the religious parties, was also for unity.In addition, many Bengalis who voted for Sheikh Mujib out of a long-standing sense of alienation and a desire for provincial autonomy, may not have been in favour of outright secession. The profound polarisation of politics reached even into individual Bengali families, dividing some of them horizontally – for example the father, who had experienced the creation of Pakistan, supported united Pakistan, while the son, swayed by the oratory of Sheikh Mujib, joined the fight for an independent Bangladesh.Shifting of the CapitalThe decision of shifting of the capital city from Karachi to Islamabad was perhaps a good step taken in the regime of President Ayyub Khan (1960) but  it hit the East Pakistanis like a bullet. The Bengalis said that massive development was taking place in West Pakistan and it was being financed from the money that belonged to East Pakistan e ntirely.Biased Nature of West PakistanInspite of the repeated protest by the East Pakistanis, they were discriminated in the appointments in the jobs. The development funds were not given to them honestly. The East Pakistanis developed a colonial attitude towards the Bengalis.Causes of the defeat in east pakistanOperation SearchlightA planned military pacification carried out by the Pakistan Army – codenamed Operation Searchlight – started on 25 March to curb the Bengali nationalist movement by taking control of the major cities on 26 March, and then eliminating all opposition, political or military, within one month. Before the beginning of the operation, all foreign journalists were systematically deported from East Pakistan.The main phase of Operation Searchlight ended with the fall of the last major town in Bengali hands in mid-May. The operation also began the 1971 Bangladesh atrocities. These systematic killings served only to enrage the Bengalis, which ultimatel y resulted in the secession of East Pakistan later in the same year. The international media and reference books in English have published casualty figures which vary greatly, from 5,000–35,000 in Dhaka, and 200,000–3,000,000 for Bangladesh as a whole, and the atrocities have been referred to as acts of genocide.Mukti BahiniIndian Secret Intelligence Services formed an Anti Pakistan Wing East Pakistan named as Mukti Bahini meaning Freedom fighters or Liberation Army, which actively participated in persuading Population of East Pakistan to demand for a separate country. The Pakistan Army launched military operations against Bengali civilians, students, intelligentsia, and armed personnel after sundown on March 25, 1971.In response, Bangladesh declared independence and Bengali military and paramilitary personnel, as well as  civilians, started spontaneous resistance against the aggression. This was the formation of the Mukti Bahini. The armed forces as well as the para military and civilian forces who fought alongside them for the liberation of Bangladesh are referred to as the Mukti Bahini.Involvement of IndiaWary of the growing involvement of India, the Pakistan Air Force (PAF) launched a preemptive strike on Indian Air Force bases on 3 December 1971. The attack was modelled on the Israeli Air Force's Operation Focus during the Six-Day War, and intended to neutralise the Indian Air Force planes on the ground. The strike was seen by India as an open act of unprovoked aggression. This marked the official start of the Indo-Pakistani War.As a response to the attack, both India and Pakistan formally acknowledged the â€Å"existence of a state of war between the two countries†, even though neither government had formally issued a Declaration of War.Third Indian-Pakistani War, December 1971Indo-Pakistani relations deteriorated yet again. This time the civil war in East Pakistan was the principal cause. After Pakistani air strikes, Indian troops entered the war (December 1971). India invaded East Pakistan in part in response to the charges of atrocities and the wave of refugees entering India. Pakisdtan conducted air raids on Indian air ports and airfields. Indians Prime Minister, Indira Gandhi, addressed the nation by radio and proclaimed that the the Pakistani war against Bangladesh has become one against their homeland. The Indians quickly defeated the Pakistani Army.Military CausesWest Pakistanis had poor equipment and an insufficient number of aircrafts which made it easier for the Indians to defeat the west Pakistanis. The 14 F-86s that were stationed in Dhaka had no night time flying capability. Their military weakness also became one of the strongest reason for failing in 1971 war.The air and naval warThe Indian Air Force carried out several sorties against Pakistan, and within a week, IAF aircraft dominated the skies of East Pakistan. It achieved near-total air supremacy by the end of the first week as the entire P akistani air contingent in the east, PAF No.14 Squadron, was grounded because of Indian and Bangladesh air strikes at Tejgaon, Kurmitolla, Lal Munir Hat and Shamsher Nagar.Sea Hawks from INS Vikrant also struck Chittagong, Barisal and Cox's Bazar, destroying the eastern wing of the Pakistan Navy and effectively blockading the East Pakistan ports, thereby cutting off any escape routes for the stranded Pakistani soldiers. The nascent Bangladesh Navy (comprising officers and sailors who defected from the Pakistani Navy) aided the Indians in the marine warfare, carrying out attacks, most notably Operation Jackpot.Islolation from the entire worldNeither America nor China was willing to support the Pakistanis because both thought that in East Pakistan there was a popular uprising of the people and both would not have suppressed it.Existential fearBack then, the Pakistani army was accused of forming militia groups to do its bidding in East Pakistan. This existential fear of a bigger, hosti le India is central to Pakistan's security paradigm. In 1971 this fear was reinforced by the crucial role India played in the break up of Pakistan. For India, the situation became serious when nearly 10 million Bengali refugees crossed the border into its territory. There was a humanitarian crisis, but also an opportunity to cut Pakistan down to size.Aftermath and surrenderThe Pakistani army surrendered at Dhaka (December 16, 1971). More than 90,000 Pakistanis, mostly West Pakistanis, became Indian prisoners of war. President Yahya Khan resigned.Bangladesh and Zulfikar Ali Bhutto took over Pakistan. The surrender led to the disintegration of East and West Pakistan and the establishment of Bangladesh. After 25 years, the East Pakistanis declared themselves independent and renamed their Province as Bangladesh.The final reaction of the nationReaction to the defeat and dismemberment of half the nation was a shocking loss to top military and civilians alike. No one had expected that they would lose the formal war in under a fortnight, and there was also unsettlement over what was perceived as a meek surrender of the army in East Pakistan. Yahya Khan's dictatorship collapsed and gave way to Bhutto, who took the opportunity to rise to power.General Niazi, who surrendered along with 93,000 troops, was viewed with suspicion and contempt upon his return to Pakistan. He was shunned and branded a traitor. The war also exposed the shortcomings of Pakistan's declared strategic doctrine that the â€Å"defence of East Pakistan lay in West Pakistan†.Pakistan also failed to gather international support, and found itself fighting a lone battle with only the USA providing any external help. This further embittered the Pakistanis, who had faced the worst military defeat of an army in decades.  Pakistan finally recognized Bangladesh at the Islamic Conference in Lahore on February 22, 1974.

Health Economics Essay Example | Topics and Well Written Essays - 500 words - 1

Health Economics - Essay Example For instance, high level of technology, decrease in the cost of production, decrease in profit obtained from other goods, and an increased number of sellers in the market will shift the curve to the right side of equilibrium. All these factors will lead to a decrease in price of the drug in question since very little cost is used in production (Taylor & Weerapana, 2011). On the contrary, Mankiw (2011) argues that if the price of inputs increases, cost of production of other goods increases, level of technology diminishes, and the number of suppliers in the market reduces, then it is expected that price of the commodity increases. These factors will shift the supply curve on the left side of the equilibrium side as a result of negative change in the market prices. Additionally, increased prices of the drug will lower its demand since very few people will be able to purchase it. On the other hand, demand curve will be affected by a several factors. For example, increase in the expected value of the good, increase in the value of a substitute, decreased price of the complementary good, increase in the number of the potential consumers and increased earnings of the consumer will lead to increased demand. This will lead to the equilibrium shifting to the right. This will lead to increased value of the drug. Moreover, when there is a decrease in expected value of the commodity, increased value of the complementary commodity, a decrease in the price of the substitute; decreased number of potential consumers and decreased income of the consumer will lead to a downward change of the curve or the curve shifts to the left hence less demand. This decreases the price of the certain drug and supply will be down. Decrease in demand leads to flooding of a certain good in the market (Arnold, 2008). Several factors impact the degree of supply curve or demand curve shift (Graves & Sexton, 2006). First, monopoly or production

Reflective Nursing in ctitical care Account of an intubation Essay

Reflective Nursing in ctitical care Account of an intubation - Essay Example That is to say, nursing has a more active role to play in the health care delivery system than the past and nursing, as a profession is 'accountable' today. The patient in this case was admitted for an acute exacerbation of COPD with the complications of Atelectasis and Cor pulmonale. Chronic obstructive pulmonary disease (COPD), also known as chronic obstructive lung disease (COLD), is a term used to describe progressive lung diseases, which include emphysema, chronic bronchitis and chronic asthma.The common symptoms of COPD are progressive limitations of the airflow into and out of the lungs and shortness of breath. Emphysema and chronic bronchitis are closely related and patients with COPD may have both, which affects lung function, preventing the lungs from bringing oxygen to the body and getting rid of carbon dioxide. Atelectasis is a condition where there is a collapse of part or all of a lung by blockage of the bronchus or bronchioles or by very shallow breathing. Atelectasis can be both acute and chronic. Acute atelectasis is the recent collapse of the lung and is primarily notable only for airlessness. In chronic atelectasis, the affected area is often characterized by a complex mixture of airlessness, infection, bronchiectasis, and fibrosis. The most common cause of atelectasis is an obstruction of a large bronchus. Smaller airways also become blocked. The obstruction is caused by a plug of mucus, a tumor, or an inhaled foreign object inside the bronchus. Alternatively, the bronchus is also blocked by a tumor, enlarged lymph nodes, or a significant amount of pleural effusion or pneumothorax in the pleural space. When an airway becomes blocked, the air in the alveoli beyond the blockage is absorbed into the bloodstream, causing the alveoli to shrink and retract. The collapsed lung tissue commonly fills with blood cells, serum, and mucus and becomes infected. Acute atelectasis is a postoperative complication, especially after chest or abdominal surgery. Cor pulmonale is the failure of the right side of the heart caused by prolonged high blood pressure in the pulmonary artery and right ventricle of the heart.The left side of the heart exerts a higher level of blood pressure to pump blood to the body.Whereas, the right side pumps blood through the lungs with a lower pressure. Thus, any condition that leads to prolonged high blood pressure in the arteries or veins of the lungs causes a condition called pulmonary hypertension.This pulmonary hypertension is not tolerated by the right ventricle of the heart and thus fails to properly pump against these abnormally high pressures leading to cor pulmonale.Chronic lung diseases like COPD or other conditions like Obstructive sleep apnea,Central sleep apnea,Cystic fibrosis causing prolonged low blood oxygen can lead to cor pulmonale.The symptoms include shortness of breath,wheezing, coughing, swelling of the feet or ankles,exercise intolerance,chest discomfort, cyanosis,distension of the neck veins indicating high right-heart pressures,abnormal fluid collection in the abdomen, enlargement of the liver,swelling of the ankles and abnormal heart sounds.

'Britain does not really have a constituton at all, merely a system of Essay

'Britain does not really have a constituton at all, merely a system of goverment.' - Essay Example Traditionally a constitution is taken as a written document clearly establishing principles and rules governing a given political body. It guarantees specified rights to nationals, establishes duties, the level of powers and important political principles of each government. With constitutions from many countries from the common wealth being written, British constitutions has never been written down. What the Britons have as their constitution is a combination of statute law, convention and common law. The 1982 Reform Act which was responsible for the parliamentary representation reforms, Magna Carta (1215) protecting the community rights against the crown and the Bill of Rights (1689) that made it impracticable for the sovereign to ignore the government wishes by extending the powers of the parliament. Though it has never been well defined, common law is presumed to come from legal precedents or customs and interpreted in court cases by the judges. Practices and rules which are not legally enforceable are called conventions but regarded as crucial to the smooth working of the government. It is from the historical events through which the British system of government has originated that conventions are extracted. For example, there is a convention holding ministers accountable and responsible for what happens in their dockets although it is not legally enforceable. A general agreement Act of parliament can amend a convention thus amending the constitution. Unlike many constitutions in the world the British â€Å"constitution† is very flexible a thing that has led to it realizing full development over the decades. Rulings of the European court of justice have coded and determined British la sections under areas covered by numerous treaties where Britain is involved. This is making the legal and constitutional document is the Magna Carta. It has sixty one classes that set out vivid community

Marketing & Entrepreneuriship Essay Example | Topics and Well Written Essays - 3000 words - 1

Marketing & Entrepreneuriship - Essay Example In order to critically evaluate the factors which determine entrepreneurial success, it is imperative to begin by explaining the meaning of entrepreneurship in order to gain a clear understanding of the whole concept. Entrepreneurship is loosely defined as the emergence and growth of new businesses. Timmons believes that entrepreneurship is the process of creating or seizing an opportunity and pursuing it regardless of the resources currently controlled. Small to medium businesses are the dominant forms of business developed by entrepreneurs in the economy and is going to be discussed below, the success of this kind of business can be attributed to many factors. For instance, venturing into a mobile business which offers fast foods is a good example of entrepreneurship given that an entrepreneur can capitalize on the opportunity of satisfying the needs of the customers who do not wish to visit restaurants. However, it is not an easy feat to successfully operate in this venture withou t taking into consideration some of the following factors. Creativity and innovation are the major factors that can lead to the success of small business. Creativity can involve the adjustment or refinement of existing procedures or products, the identification of opportunities and the identification of solutions to problems. Basically, creativity involves new ideas and every person who establishes an enterprise, adds value and strives to ensure that the enterprise continues to exist and this person is involved in economic creation.

Employment, labor and anti-discrimination Essay Example | Topics and Well Written Essays - 250 words - 1

Employment, labor and anti-discrimination - Essay Example 1). Applying this law in the case of Sam who works as a driver for Toxic Games Warehouse, a wholesale distributor and online retailer of video games and accessories, he could in fact file a complaint with the EEOC for his employer’s repeated denial of promotions to the position of dispatcher for no valid reasons. As indicated,. Sam meets the requirements for the job, which are a years driving experience and a specific license. Therefore, it is obvious that the employer violates this law by discriminating against Sam and denying his promotions. Likewise, by virtue of this law, when Sam files his complaint with the EEOC, his employer could not retaliate since there were no legal and valid grounds for refusing Sam to be promoted, as applied. Having worked for Toxic Games Warehouse for 10 consecutive years, in conjunction with the skills he possess which are needed for the next higher level position, should make Sam more than just qualified to be promoted to the next higher

Ransomware Research Paper Example | Topics and Well Written Essays - 750 words

Ransomware - Research Paper Example The way the ransomware attacks a computer system is similar to the way a computer worm operates. This means that a ransomware uses the route of downloaded data and it may even enter a computer system through a network that is vulnerable against such attacks and is not properly secured. Ransomware developers use payload to password protect personal files of a user, encrypt data that is textual in nature or minimize the users communication with his/her personal computer by displaying notices that the system has been used for illegal purposes, it even overrides files in the windows registry area such as the file of explorer.exe or restrict the user from being able to use the system until the user has not repaired the entire system. The system of coercing the computer user through display of messages is regarded as scareware. The first ever created ransomware was created by Joseph Popp who named his ransomware as PC Cyborg Trojan (Emm, 2008, p.15). In this ransomware the developer had developed a payload that used to state that the license of a particular software has been expired and the ransomware even used to password protect the softwares on the hardrive and use to coerce the user into paying an amount of $189 to the developer if the user wanted to reuse the software or unlock the encrypted system. Josephy was caught by the criminal justice system and he was recognized as mentally unfit, Josephy gave his earned money to help in funding AIDS related research. During the season of 2010, ten people were arrested by the local authorities of Russia for developing a ransomware named as WinLock (Celtnet, 2012). This ransomware was indulged in the act of displaying images that were pornographic in nature and used to coerce the users into sending a premium rate text message which was priced at $10 in order if the users wanted to unlock their computer systems through a code. The developers of this ransomware earned more than $16 million; this ransomware did not use the technique of encrypting files and computer systems. During the year of 2012 a huge ransomware named as Reveton which was even recognized with the nick name of Police Trojan started spreading in US. This ransomware displayed a message on the user’s pc stating that the law enforcement organizations have detected illegal activities conducted on the computer system. For example: viewing and downloading of softwares that are pirated in nature and downloading of pornographic material. The playload used by this ransomware required users to reimburse the authorities by utilizing a voucher from an unknown cash service that was prepaid in nature. To increase the fear of the law enforcement agency, the developers used to display the IP address used by the user and the ransomware even showed the users that the intelligence agenc ies are recording their activities. During the month of August 2012, the developers of Reveton attacked US computer system and the message displayed by the playload stated that the user has to compensate for their illegal activities by paying a total of $200 to the FBI through MoneyPack card (PERLROTH, 2012). Defense Several methods have been identified by security software developers and other software develope

The Missing Link in Conflict resolution Essay Example | Topics and Well Written Essays - 2250 words

The Missing Link in Conflict resolution - Essay Example IGD also aims to identify differences across the groups brought together and to improve the capabilities of both individuals and groups to achieve social justice (Nagada and Gurin 2007, 35). This paper compares and contrast the conflict processes operative for Northern Ireland, South Africa and the Israeli/Palestinian conflicts. The object is to identify what if any of the IGD theories are reflecting in these three conflict resolution process. The South African Truth and Reconciliation Commission (TRC) is characterized as among the country’s â€Å"most effective† conflict resolution processes to date (Gibson 2006, 409). The TRC has contributed significantly to South Africa’s democratic reforms by influencing a â€Å"more reconciled society† (Gibson 2006, 409). The conflict resolution process in Northern Ireland takes a similar holistic approach in that the conflict resolution process is centered around policies and initiatives designed to foster equality and to â€Å"improve community relations† (Cairsn and Darby 1998, 754). The School of Peace approach to the Israeli/Palestinian conflict resolution is slightly different in that the process aims to heighten individual awareness of the conflict, their part in it and the facilitation of identities via intergroup interactions (Halabi and Sonnenschein 2004, 49). IGDs are built around bringing together between 12 and 16 students once a week for between ten and fourteen weeks. These students convene under the leadership of a â€Å"trained peer† who instructs from a plan that merges several learning initiatives which include â€Å"intellectual and effective engagement†; â€Å"individual reflection and group dialogue†; â€Å"individual intergroup and institutional analyses†; â€Å"affinity-based and heterogeneous groupings;† and â€Å"individual and collective action† (Nagada and Durin 2007, 35). IGD takes the position that the social justice education typically fails to implement tools of intergroup interactions

Hiring a New Bartender Essay Example | Topics and Well Written Essays - 750 words

Hiring a New Bartender - Essay Example ch as determining the need for recruiting, conducting a job analysis, writing a job description and specification for the candidate, fixing the appropriate salary, deciding how and where to find the prospective employees and interviewing them ("The Interview Process: Selecting the right person† par. 2). Mr. Peter Luger has the task of hiring a new bartender. There are four applicants for consideration and as such, he will have to scrutinize every person’s skill and level of qualification before making his choice. John is twenty-five years of age; therefore, he is mature enough to handle the pressures of having to work with the presumably aged people who visit the bar. Since the bar has been in existence for ten years, Luger wouldn’t want to tamper with the reputation that he has already built. At twenty-five, John is neither too old to handle the job nor too youthful to mishandle the patrons of the bar. The fact that he is a college graduate implies that he has the required academic qualifications for the job at hand. John is also experienced in the restaurant business; therefore, there should be no problem on his side handling the clients’ food. Serving alcohol represents a new challenge for the man but since he is an adventurous person, selling alcohol would offer no difficulties for him. Mr. Luger’s sports bar and grill closes late in the night and as such, it is necessary for the bartender to be willing to comply with the owner’s wishes. John has his own means of transportation; therefore, Luger should have no problem convincing the bartender to leave the bar late at night. The only point of John’s undoing is his temper. High tempered individuals may not be the best persons to hire in a position that requires tolerance such as that of being a bartender. It is common knowledge that drunken people are bound to behave arrogantly and sometimes abusively, therefore, this might not bode well for John. Should John lose his temper while handling some of

Kobe Bryant and Lebron James Essay Example for Free

Kobe Bryant and Lebron James Essay Introduction In today’s world whenever somebody talks about the most favourite players then Kobe Bryant and Lebron James come on the top of the list just because of their remarkable performances and their young age achievements. They both have started their sports career from the school age and then they excelled in their respective sports of basketball. They both play for American National Basketball Association (NBA). Kobe Bryant plays as a shooting guard for the Los Angeles Lakers and Lebron James plays for the Miami Heat. Lebron James also referred as a King James just because of his moves and his utmost versatility in basketball. Who is better Leader? It is really difficult to entitle one of them as a better player than other because both players have their separate recognition in the world of basketball. They both play as the backbone for their teams. Well if we look in the last season of sports then we will definitely find some remarkable knocks from the Lebron James. Lebron strived a lot in last season and struggled a lot with his teammates to turn the really hard matches into easy victories. Although, Kobe has great understanding with his teammates and his manager but sometimes due to the short temperedness he losses control on his tempo and takes some wrong moves that eventually count very negative impact on scoreboards. Trudell, (2012) defines â€Å"on the contrary Lebron has great quality to work with his teammates and lead them from the front†. This leading quality differentiates Lebron from Kobe to a greater extent and it also contributes towards his match wining performances as well. Key Differences between them They both are simply perfect in their teams. It is really hard to find any difference between these two worlds recognised players. There are following differences between them: Style of playing Both players have marvellous style in on screen and off screen. If we try to elaborate their style in the court then we will definitely come up with the opinion that Lebron always prefers to play in very defensive mode while maintaining the decorum of the game. On the contrary Kobe tries to be bit aggressive during the match and if he finds any injury in opponent player then he will turn that injury as a great weakness of the opponent team. Trudell (2012) cleared that â€Å"Lebron has more humanitarian attitude towards game†. Team Individual performance When we talk about the Lebron then we observe that he takes his team member along in entire match but when it comes about the Kobe then he always prefer to have individualistic approach to prove his abilities and skills and try to prove himself as a single shining moon on a sky (Armstrong, 2007). Past Performance They both are highly sincere with their profession and in the court they are perfect players. If we consider the rating of both players then we will clearly find that Kobe stands higher then the Lebron, his rating is 4.0/5 on the world ranking chart on the other hand the Lebron rating is 3.7/5. These ratings clearly differentiate their style of playing and their performance in past couple of years. William (2010) once said, â€Å"Although, it is fact that Kobe started his career in 1996 that is far earlier than the Lebron, so his efforts and his performances are better then Lebron in all aspects. They both meet their audiences’ expectations all the time by performing their best†. Who is better Player? On the basis of individual approach and stamina we can say that Kobe has better understanding towards game and he can all alone give very tough time to the opponents. Only on this basis we cannot degrade the Lebron because it is a fact that Lebron is playing really well nowadays and he has proved that he can make his team motivated enough to turn all the hard and tough situations in to their favour (Armstrong, 2007). Lebron never appeared in any kind of team distracting drama due to his friendly and kind behaviour on the contrary Kobe has been caught several times in these kinds of issues that have created very negative impact on his gaming personality. Audience Support for both players When we talk about the audience support then obviously time always matter. Since Kobe is older player than Lebron that is why his fan following is comparatively greater than the Lebron. If we look to the vote board then we will find that audience always prefer to vote the Kobe just because of his better style of playing and shooting against the opponent team. This kind of Kobe’s style always supports him to win the match. William (2010) defined, â€Å"he is not only a player for his team he is actually a robot that can judge the opponent’s strategies in a start of a match and then he devises his strategies to break all schemes of the opponent players†. Conclusion It is fact that winning matches is the best statistics of all and it is the only option we are left with to gauge a player performance by analysing his match wining scores and performance. If we look into the performance of both players who contributed towards a match wining performances then we will obviously vote to the Kobe for his unbeatable performance. Kobe has appeared in 4 NBA championships with 3 wining performances and he is still looking forward to more championships with high spirits of wining and turning down the opponents. On the contrary in case of Lebron it is not possible to participate in championship yet just because of his strong opponent player and that is obviously Kobe. But it is again a matter of fact that Lebron has long way to go because he is comparatively newer than Kobe and he has more passion. In the end we can say that Kobe is an unbeatable king of this basketball planet and no body can surpass him just because of his aggressive attitude towards playing and making his opponent helpless in the game. He never believes in any kind of humanitarian behaviour during game when he is out there to play then only one thing he keeps in his mind and that is victory and in order to turn that thinking into reality he utilises his full potential and eventually he comes out with flying colour. Statistical Analysis References Trudell, Mike (2012). Kobe Surpasses 29,000 Points. NBA.com (Turner Sports Interactive, Inc), Retrieved March 10, 2012. Armstrong, Kevin (2007). End of an era: Vaccaro closes ABCD camp as he eyes hoops academy. Sports Illustrated. Retrieved September 2, 2010 William Rhoden (2010). Cleveland’s Venom Validates James’s Exit, The New York Times, Archived from the original on November 9, 2010, Retrieved November 9, 2010 Adande, J. A (2010). Gilberts letter signals wider backlash. ESPN, Retrieved July 13, 2010

Contributions of Functionalist Approaches to Translation

Contributions of Functionalist Approaches to Translation INTRODUCTION The 1980s saw the birth of a number of approaches to Translation Studies (TS henceforth) collectively termed functionalist, which brought about a paradigm shift in the system. This essay examines the strengths and weaknesses as well as the contributions of these functionalist approaches to the field of TS. Structurally, the essay starts with a brief historical overview of the approaches to translation before the advent of functionalist approaches. Then it discusses the major functionalist approaches, highlighting their major postulations and the criticisms against them, which will then be followed by a general summary of the various contributions of the various strands of functionalism. TRANSLATION STUDIES BEFORE FUNCTIONALISM Over the years, scholars have approached the discipline of Translation Studies from various angles largely depending on the dominant philosophy of the time and/or underlying conceptions of the nature of translation and how the translated text will be used (Schaeffner 2001: c5). However, one dilemma that has prevailed over the centuries is the decision on the best method of translating a text. This dilemma of the best method of translating is an age-old one. Jerome (395/2004: 24) expresses this dilemma thus: It is difficult, when following the lines of another, not to overshoot somewhere and arduous, when something is well put in another language, to preserve this same beauty in translationif I translate word by word, it sounds absurd; it out of necessity I alter something in the order or diction, I will seem to have abandoned the task of a translator. However, Jerome and indeed many other translator of his time end up not translating word by word. He quotes Cicero as observing that in his translation of Platos Protagoras and Xenophones Oeconomicus, that he kept their meanings but with their forms their figures, so to speak in words adapted to our idiom (395/2004: 23). He adds that except for the case of Sacred Scriptures, where the very order of the words is a mystery I render not word for word, but sense for sense (395/2004: 25) so as not to sound absurd in the target language. These scholars, including others like Nicolas Perrot DAblancourt (1640/2004), Martin Luther (1530) and John Dryden (1680/2004), may not be seen as translations scholars per se since they all had their respective vocations and translation was what they did in the passing. However, their views and comments formed the bedrock on which the field of translation studies was to be built. Linguistic-based approaches The argument over word by word or sense for sense translation prevailed over the centuries up till the 20th century when Jakobson (1959/2004) introduced the term equivalence in the literature and Nida (1964/2004) expands it by distinguishing between formal and dynamic equivalence. While formal equivalence aims at matching the message in the receptor language as closely as possible to the different elements in the source language, including the form and content, dynamic equivalence aims at complete naturalness of expression, and tries to relate the receptor to modes of behaviour relevant within the context of his own culture (Nida 1964/2004: 156). According to Nida, the purposes of the translator to a large extent determine whether the translator should aim at formal equivalence or dynamic equivalence. One observes that these scholars are concerned with the correspondence between the target language and the source language and these approaches were thus collectively called linguistic approaches to translation. According to Saldanha (2009: 148), the term linguistic approaches to translation studies is used to refer to theoretical models that represent translation and/ or interpreting as a (primarily) linguistic process and are therefore informed mainly by linguistic theory. Translation studies was subsumed under applied linguistics and thus studied with methods developed in linguistics (Schaeffner 2001: 6). Other scholars that contributed to research in this area are Catford (1965) and House (1977/1981). Translation was seen as a transfer of information from one language to another, as an activity that affects just the two languages involved. Thus scholars were concerned with prescribing methods of translating from one language to the other in order to reproduce in the target langua ge a message that is equivalent to that of the source text. One such prescription was Vinay and Dabelnets (1958/2994) seven methods or procedures for translation: borrowing, calque, literal translation, transposition, modulation, equivalence and adaptation. The first three they call direct translations as they involve transposing the source language message element by element, while the last four they call oblique because they involve an upsetting of the syntactic order of the source language. One major shortcoming of linguistic approaches is that they do not take cognisance of the contribution of the context in which an expression is used to the understanding of the whole message or text. Schaeffner (2001: 8 9) observes that Studies conducted within a linguistic-based approach to translation concentrated on the systematic relations between units of the language systems, but often abstracted from aspects of their contextual use. A chosen TL-form may well be correct according to the rules of the language system, but this does not necessarily mean that the text as a whole appropriately fulfils its communicative function in the TL situation and culture. Working on the translation of the Bible, Nidas distinction between formal and dynamic equivalence introduced aspects of sociolinguistics and culture into translation studies. He says that any discussion of equivalence, whether formal or dynamic, must consider types of relatedness determined by the linguistic and cultural distance between the codes used to convey the message (1964/2004: 157). He declares that a natural translation or dynamic equivalence involves two principal areas of adaptation, namely, grammar and lexicon (2004: 163). However, his theory has been criticised for being restricted in application and scope as it appears to be meant mainly for Bible translations and to focus on just lexical and syntactic correspondence. A few years later, Koller (1979: 215f) proposes five categorisation of the concept of equivalence namely: textralinguistic facts/state of affairs (denotative equivalence); form of verbalisation, including connotations, style and (connotative equivalence); text norms and language norms (text-normative equivalence); TL-text audience (pragmatic equivalence); and specific aesthetic, formal , characteristic features of text (formal-aesthetic equivalence) (quoted in Schaeffner 2001: 9) This too receives a lot of criticisms which apparently inform its review by the author over the years. Pym (1997: 1) observes that four editions of Kollers book Einfà ¼hrung in die ÃÅ"bersetzungswissenschaft (Introduction to Translation Studies/Science) has been published as at 1995, with an article summarising the main points appearing in English in Target. Indeed the concept of equivalence was (and still is) highly controversial even to this day. Textlinguistic approaches In reaction to the apparent rather restricted linguistic scope of these approaches, some scholars then argue for a text-linguistic or pragmatic approach to translation, whereby the whole text is seen as the unit of meaning and translation, as against the lexicon and grammar which was the focus of linguistic approaches. Katharina Reisss (1971/2004) text-typology is seminal in this respect, being about the first to introduce into TS a consideration of the communicative purpose of translation (Munday 2008: 74). According to Reiss, the communicative function of a text in its source culture determines its function in the target culture and how it will be translated. She classifies text-type into informative (communicates content), expressive (communicates artistically organised content) and operative (communicates content with a persuasive character) (Reiss 1971/2004: 171). In her view, a text that is adjudged informative should be translated in such a way that the same content in the sou rce text is transferred into the target text; an expressive text should retain the artistic and creative features of the source text in the target text; while an operative source text should inform a target text with a similar or analogous effect on the target audience. In situations where a text exhibits features of more than one text-type, the translator should concern themselves with foregrounding the overriding text-type and back-grounding the rest if the need so arises. Reiss does a lot to stress the importance of text-variety or genre in translation studies. She observes that genre conventions are culture specific and the translator should consider the distinctions in genre conventions across culture so as not to endanger the functional equivalence of the TL text by naively adopting SL conventions (1971/2004: 173). Neubert (1985) and its sequel co-authored with Gregory Shreve (1992) have done a lot to emphasise the importance of genre analysis in translation studies. In the pr eface to Translation as Text, they observe the decline in influence of linguistics in translation studies and the movement towards interdisciplinarity: Translation studies has abandoned its single-minded concern with strictly linguistic issues. It has been invigorated by new ideas from other disciplines. Translation scholars no longer hesitate to adopt new ideas from information science, cognitive science, and psychology. (Neubert and Shreve 1992: vii) Scholars that favour this approach focus a lot on setting up prototypes of genres, or as Corbett (2009: 291) puts it, these scholars focused on the descriptions of highly predictable, ritual, transactional texts, many of which seem banal in nature like Swales (1990) on reprint requests and Eggins (1994) on recipes. Thus scholars tried to identify parallel texts across languages and cultures by doing a systematic comparison of genre exemplars in both the source culture and the target culture (Schaeffner 2001: 11). Schaeffner also notes elsewhere that [g[enre conventions are determined by culture and, thus, prone to constant change (2000: 222). This enables the translator to adapt the text to the conventions of the receptor or target culture. Thus scholars operating within a text-linguistic approach to translation believe that a translation goes beyond language to cultural considerations. FUNCTIONALIST APPROACHES The second half of the 20th century witnessed some paradigm shift in translation studies, especially with the publication in German of Katharina Reiss and Hans Vermeers Foundation for a General Theory of Translation and Justa Holz-Manttaris Translatorial Action: Theory and Method, both in 1984. These set the pace for what is later known as functionalist approaches to translation, approaches that see translation as a communicative action carried out by an expert in intercultural communication (the translator), playing the role of a text producer and aiming at some communicative purpose (Nord 2001: 151). Functionalist approaches generally believe that the function of a text in the target culture determines the method of translation. They are said to have developed in opposition to the equivalence paradigm of the linguistic-based approaches which see the source text as what determines the nature of the target text. Using the communication scheme of SOURCE-PATH-GOAL, they accentuate the importance of the target text as the goal of the translational process. One of the major proponents, Vermeer (1987: 29) declares that linguistics alone is not effective because translation itself is not merely nor primarily a linguistic process, and that linguistics has not yet formulated the right questions to tackle our problems (cited in Nord 1997: 10). Quite a good number of translation scholars subscribe to functionalism like Vermeer (1978, 1989, 1996; Reiss and Vermeer 1984, 1991; Nord 1997, 2005; Holz-Manttari 1984, 1993; Honig 1997; Honig and Kussmaul 1982, 1996; among many others. Following are some of the major strands of functionalism. Skopostheorie The most popular among the functionalist approaches, skopos theory was developed in Germany by Hans Vermeer in 1978 in dissatisfaction with the linguistic-based approaches to translation. He sees translation as an action governed by a skopos from Greek meaning purpose or aim. This purpose now determines how the translation is done. Vermeer argues that the source text is produced for a situation in the source culture which may not be the same in the target culture. It then follows that the translation should be produced to suit the purpose for which it is needed in the target culture: the source text is oriented towards, and is in any case bound to, the source culture. The target textis oriented towards the target culture, and it is this which ultimately defines its adequacy (Vermeer 1989/2004: 229). Reiss and Vermeer jointly published Translatorial Action: Theory and Method in 1984 to give what has been described as the general translation theory, sufficiently general, and sufficient ly complex, to cover a multitude of individual cases (Schaeffner 1998: 236). They see a text as an offer of information and translation as an offer of information existing in a particular language and culture to members of another culture in their language. They hold that the needs of the target text receivers determine the specification of the skopos and the selection made from information offered in the source text (Schaeffner 1998: 236). Thus translation goes beyond linguistic considerations to also encompass cultural issues. The question then arises: Who determines the skopos? According to Vermeer (1989/2004: 236), the skopos is defined by the commission and if necessary adjusted by the translator. Nord (1997:30) adds that the skopos is embedded in the translation brief, which means that the person initiating the translation invariably decides what the skopos is. She agrees with Vermeer that the skopos is often negotiated between the client and the translator. The skopos of a text in the source culture might be the same as the skopos of the translation in the target culture, but that is just one of the different purposes for which a text might be needed in a different culture as the purpose in the target culture might be different. Reiss and Vermeer (1984) call the situation where the source text function is the same as the target text function functional constancy, while for the other situation where both texts have different functions they say the text has undergone a change of function. Vermeer also gives two further rules: coherence rule and fidelity rule. Coherence rule stipulates that the target text must be sufficiently coherent for the target audience to understand given their assumed background knowledge and situational circumstances while the fidelity rule focuses on the intertextual relationship between the source text and the target text (Schaeffner 1998: 236). The nature of this intertextual coherence between the source text and target is however determined by the skopos. The theory of translatorial action This theory, proposed by Holz-Manttari, draws a lot from action theory and communication theory. An action is generally seen as doing something intentionally, and communication basically means transferring information from one entity to another. Holz-Mantarris theory then sees translation as transferring information embedded in one culture to receivers in another culture, and the translator is the expert saddled with the responsibility of this information transfer. Using concepts from communication theory, Holz-Mantarri identifies the players in the translatorial process: the initiator, the person in need of the translation; the commissioner, the person that contacts the translator; the source text producer or author; the target text producer, the translator or translation agency; the target text user, teachers for example; and the target text recipient, for example students in a target users class. She does a lot to emphasise the role played by these participants in the translationa l process. The need for a translation arises in situations where there is information in a particular culture that members of another culture do not have access to as a result of the cultural differences among the communities, or as Nord (1997: 17) puts it, situations where differences in verbal and non-verbal behaviour, expectations, knowledge and perspectives are such that there is not enough common ground for the sender and receiver to communicate effectively by themselves. Translation then is a process of intercultural communication aimed at producing a text capable of functioning appropriately in specific situations and contexts of use (Schaeffner 1998: 3). And since the focus is on producing functionally adequate texts, the target text should then conform to the genre conventions of the target culture. This makes the translator the expert in translatorial action, who determines what is suitable for the translatorial text operation and ensures the information is transmitted satisfactorily. One interesting aspect of this theory is the introduction of new terminologies into the literature. For example, instead of text, Holz-Mantarri prefers Botschaftstrà ¤ger, message carrier, a concept that broadens the traditional concept of text to include non-verbal aspects of communication thereby doing justice to the complexity of communicative processes (Martin de Leon 2008: 7). Other changes include Botschaftstrà ¤gerproduktion for text production and translatorisches Handeln for translate or translation. The principle of the necessary degree of precision This principle was developed by Honig and Kusmaul to provide a more detailed account of translation relevant decision-making processes as against the framework theory of translation (Honig 1997: 10). One of the outcomes of functionalist approaches is that the translator can give more information in the translation if the skopos requires that. An instance is making clear in a target text what is not so clear in the source text. However, it is not clear to what extent the translator can exercise this liberty. To this end, the principle stipulates that what is necessary depends on the function of the translation (Honig 1997: 10). Honig illustrates this in this rather long quote: the term public school implies such a large amount of culture-specific knowledge that it is impossible to render its meaning completely in a translation. Within a functionalist approach, however, the function of a word in its specific context determines to what degree the cultural meaning should be made explicit. In a sentence such as (my emphasis): (2a) In Parliament he fought for equality, but he sent his son to Eton. the translation will have to be different from translating the identical term Eton in the sentence: (3a) When his father died his mother could not afford to sent him to Eton any more. The following translations would be sufficiently detailed: (2b) Im Parlament kà ¤mpfte er fà ¼r Chancengleichheit, aber seinen eigenen Sohn schickte er auf eine der englischen Eliteschulen. (one of the English elite schools) (3b) Als sein Vater starb, konnte seine Mutter es sich nicht mehr leisten, ihn auf eine der teuren Privatschulen zu schicken (one of the expensive private schools). Of course, there is more factual knowledge implied in the terms Eton or public school than expressed in the translation, but the translation mentions everything that is important within the context of the sentence, in other words, the translation is semantically precise enough. (1997: 11) Here the translator does not aim at an exact or perfect target text, but a text that is sufficiently good enough for the situation. The translator provides as much (or less) information as the readers need as determined by the skopos. Christiane Nord Christiane Nord is one of the major proponents of functionalism. She agrees with Vermeer that the situation under which a target text is produced is different from that of the source text in terms of time, place (except for simultaneous interpreting), and sometimes medium. Thus the meaning of a text is found beyond the linguistic code, in the extratextual situation. In fact, she even stresses that meaning interpretation depends a lot on the personal experience of the text user: A text is made meaningful by its receiver for its receiver. Different receivers (or even the same receiver at different times) find different meanings in the same linguistic material offered by the text. We might even say that a text is as many texts as there are receivers of it. (2001: 152) Nord however has some reservations for the unrestricted freedom Reiss and Vermeer, and Holz-Manttari have given the translator to produce a target text of whatever form so long as it conforms to the skopos as directed by the client. To check this, she introduces the concept of loyalty which she defines as the responsibility translators have towards their partners: translators, in their role as mediators between two cultures, have a special responsibility with regard to their partners, i.e. the source text author, the client or commissioner of the translation, and the target text receivers, and towards themselves, precisely in those cases where there are differing views as to what a good translation is or should be. (Nord 2006: 33). Nord thus contends that the skopos is not the only determining factor in translation, that loyalty is necessary. Loyalty commits the translator bilaterally to the source text and target text situations: not to falsify the source text authors intentions (Nord 2005:32) and fulfilling the expectations of the target audience or explaining in a footnote or preface how they arrived at a particular meaning. Loyalty is different from fidelity or equivalence in that the latter refer to the linguistic or stylistic similarity between the source and the target texts, regardless of the communicative intentions involved while the former refers to an interpersonal relationship between the translator and their partners (2001: 185). Christiane Nord also elaborates on the possible range of functions a target text may have, different from that or those of the source text. She first distinguishes between documentary translation and instrumental translation. Documentary translation is such that aims at producing in the target language a kind of document of (certain aspects of) a communicative interaction in which a source-culture sender communicates with a source-culture audience via the source text under source-culture conditions (1997: 138); instrumental translation, on the other hand, aims at producing in the target language an instrument for a new communicative interaction between the source-culture sender and the target-culture audience. A documentary translation usually results in a target text with a meta-textual function or secondary level function according to House (1977). An instrumental translation may have the same range of functions as the source text, whereby it is said to be equifunctional; but if th ere are differences in the functions of both texts, the case is said to be heterofunctional. Nord also talks about homologous translation, also called creative transposition (Bassnet 2002: 24), where the target text represent the same degree of originality as the original in relation to the respective culture-specific corpora of texts. One other seminal input of Nords into functionalism is her call for an elaborate analysis of the source text before translation proper. Unlike Vermeer and Holz-Manttari who almost make the source text so invisible, Nord rather gives some attention to it since it is the provider of the offer of information that forms the basis for the offer of information formulated in the target text. She argues that the pre-translation analysis of the source text helps in deciding on whether the translation project is feasible in the first place, which source text units are relevant to a functional translation, and which strategy will best produce a target text that meets the requirements of the brief (Nord 1997: 62). Nord goes further to identify and categorise the kind of problems a translator might encounter pragmatic, convention-related, interlingual and text-specific and also steps to follow in the translational process. Schaeffner (2001) has done a critical review of Nords postulations (and indeed other functionalist approaches) and their applicability in practical translation. CONTROVERSIES SURROUNDING FUNCTIONALIST APPROACHES TO TRANSLATION Expectedly, functionalist approaches have received a lot of criticism, especially from scholars of the linguistic-based approaches, one of which is the definition of translation. Critics of skopos theory argue that not all target texts based on a source text can be called translations, that skopos theory makes no distinction between a real translation and adaptation or what Koller (1995) calls nontranslation. They argue that the supposed dethronement of the source text and focus on the target text (Newmark 1991; Schreitmuller 1994) subverts the intrinsic meaning of the translation. Pym (1997) argues in this light and supports Koller (1995) in upholding equivalence and calling on functionalists to distinguish between translation and nontranslation. However, functionalists view translation from a broader perspective, as any translational action where a source text is transferred into a target culture and language Nord 1997: 141). They see the linguistic-based definition as being restri ctive and in need of expansion. Linked to this is the supposed dethronement of the source text and emphasis on the skopos as the determining factor of how the translation is done. It is then argued that functionalism gives translators the freedom to produce any kind of target text and call it a translation. Pym (1991), for instance, accuses functionalists of producing mercenary experts able to fight under the flag of any purpose able to pay them (1991: 2). Nord responds to this by introducing the concept of loyalty, which restricts the liberty of the translator as they are now expected to be loyal to the source text author as well as other partners in the translational process. She also insists on an elaborate source text analysis before translation for a better understanding of both the source text and source culture which will then engender some high level coherence between the source text and the target text. One other controversy surrounding functionalism is the myriad of terminologies introduced and used differently, especially those by Holz-Manttarri. Indeed many of these criticisms still go on to this day. However, despite the various controversies surrounding the development and thrust of functionalist approaches, their contributions to the study of translation are remarkable. CONTRIBUTIONS OF FUNCTIONALIST APPROACHES TO TRANSALTION STUDIES One major contribution of this approach is that, according to Nord (1997: 29), it addresses the eternal dilemmas of free vs faithful translations, dynamic vs formal equivalence, good interpreters vs slavish translators, and so on. Thus a translation may be free of faithful or anything between these two extremes depending on its skopos or the purpose for which it is needed. The translator no longer has to always go back to the source text to solve translational problems, rather they base their translation on the function of the text in the target culture. Functionalist approaches liberate translation from theories that impose linguistic rules upon every decision (Pym 2010: 56). They recognise that the translation process involves more than languages involved and requires the consideration of these extra-textual and extra-linguistic factors for its actualisation. Thus they introduce the cultural dimension to translation studies and break the unnecessary recourse to the authority of the source text. While linguistics-based approaches may be said to be retrospective in that they look back at the source text as the model for the target text, functionalist approaches are seen as prospective in that they look forward to the function of the text in the target culture as the major determining factor for how the translation will be done. A retrospective translation operates a bottom-up process, works from source language elements and transfers the text sentence by sentence, or phrase by phrase. But a prospective translation operates a top-down process, starting on the pragmatic level by deciding on the intended function of the translation and asking for specific text-typological conventions, and for addressees background knowledge and their communicative needs ( Ouyang 2009: 104). Functionalist approaches are flexible and general enough to account for a wide range of translational situations. Talking about the theory of skopos theory for example, Schaeffner (2001: 15) observes that [t]his theory is presented as being sufficiently general to cover a multitude of individual cases, i.e. to be independent of individual languages, cultures, subject domains, text types and genres. Interestingly, the consideration of extra-textual factors in the translational process accentuates the multidisciplinary nature of translation studies. The introduction of text-typology and considerations of genre-conventions introduces elements of pragmatics, text-linguistics and culture studies into the discourse. So also is the belief that a text does not have a stable intrinsic meaning, but that meaning is affected by the subjective translator as well as by the cultural, historical, ideological and historical circumstances surrounding the production of the text (Schaeffner 2001: 12). Tied to the quality of flexibility mentioned above is functionalisms apparent accommodation of the shortcomings of some other translation theories. For example, Baker (2007) criticises the polysystem theory (Even-Zohar 1990) and Tourys (1995) theory of norms for encouraging analysts to focus on repeated, abstract, systematic behaviour and privileging strong patterns of socialization into that behaviour and for glossing over the numerous individual and group attempts at undermining dominant patterns and prevailing political and social dogma (Baker 2007: 152). She also expressed some dissatisfaction with Venutis dichotomies of foreignizing and domesticating strategies (Venuti 1993, 1995), also called minoritizing and majoritizing strategies (Venuti 1998), for, inter alia, reducing the intricate means by which a translator negotiates his or her way around various aspects of a text into a more-or-less straightforward choice of foreignizing versus domesticating strategy (Baker 2007: 152). However, these criticisms have been adequately taken care of by functionalist approaches whose methodology would not be seen as been that straitjacketed, with no room for flexibility. By their very nature, functionalist approaches bridge the gap between mere theorising and the practice of translation, as they suggest practical ways of going about translational problems. Before the advent of functionalist approaches, the translator is rarely noticed. Emphasis was on the source text and its supposed equivalent, the target text. No attention is paid to the identity or status of the translator in the translational process. On the one hand, the translator is seen as not being original, as merely performing a technical stunt (Honig 1985: 13) of transferring an original authors ideas into a different language. On the other hand, the translators identity is hidden when they produce texts that sound so fluent in the target culture as it they wer