Suffering in the ancient, Roman and Greek periods

Introduction Suffering has been conspicuous in human race for centuries. In fact, every human being has suffered in one way or another. Suffering crisscrosses all cultures of humankind. Suffering has no limit. To some people, it is part of life while to others it is a punishment from the gods. Besides, to some people it acts as a corrective measure while to other it acts as evil.Advertising We will write a custom essay sample on Suffering in the ancient, Roman and Greek periods specifically for you for only $16.05 $11/page Learn More Different people from diverse cultures define suffering in variant ways. However, the processes they undergo during suffering tend to converge. This paper will explore the theme of suffering in the ancient, Roman and Greek periods (Steiner, 1906, p. 1). Suffering Every human finds him/herself facing suffering. It comes with or without invitation. Suffering may come as a warning figure or as an enigmatic one. Suffering has tr oubled man since the beginning of the world. Based on different views, religious sectors have believed that suffering started with the sin of Adam in the garden of Eden. On the other hand, others have believed that it began with man once he came into being. However, one convergence is that suffering has formed part of human race ever since. Ancient people experienced suffering as well as the modern ones. In this regard, suffering has traversed humankind. Whenever people try to value life, they find it necessary to consider the input of suffering in it. Suffering has been considered as the eradicator of peace. Moreover, it has also been considered as a damper of hope and pleasure. However, it is necessary to note that world and cultural developments have worked to reduce human suffering (Reisinho, 2012, p. 1). Ways in which suffering is mirrored Ancient stories tell of individuals who suffered from many issues, which affected their physical conditions. Among these included Cicero and Philoctetes who experienced despair and depression in their public and private lives. Archeologists have also managed to prove conditions of suffering in the ancient worlds. They have unleashed a number of personal as well as environmental factors that contributed to suffering in ancient times. These included torture, mental anguish and depression, social and political oppression, physical handicap and chronic illnesses, among others. Notably, suffering was highly prevalent in ancient world since they experienced tyrannies, poor infrastructure, and mythical cultural aspects.Advertising Looking for essay on history? Let's see if we can help you! Get your first paper with 15% OFF Learn More Suffering in Greek society was interpreted in many ways. For instance, Aeschylos, a tragedian saw it as a way of acquiring knowledge in ancient Greek. In essence, he saw it as something that brings both the benefit and detriment. In fact, Greek philosophers believed that suffering wa s experienced deeply by people who valued life. Moreover, Selenus found it wise for a man not to be born since it only brought him/her suffering. However, influence from religion also made some Greeks to accept suffering as part of life since sin, evil and suffering are bound together (Reisinho, 2012, p. 1). It can also be noted that in the ancient western culture, suffering was seen to result from a defective universe. In this regard, some theorists in that era thought that the universe had a defective nature and thus an evil quality. For instance, Hippocrates believed that this defective nature of the universe came about due to the differences between qualities and elements of space. On the other hand, Christians believed that suffering came from original sin. Still, other theorists like Manichees believed that suffering came about because the creator made derisory work by the creator he believed to be a demiurge. Again, others like Stoic refused to acknowledge the existence of su ffering. Furthermore, Galen and Aritole believed that suffering was felt by an emotional soul. In essence, the ancient, Greek, and Roman periods understood suffering in divergent ways ranging from discipline to defect, among others (Pilch, 1990, p. 1). Similarity and Differences Between Suffering in Ancient and Suffering in Modern World It can be noted that in all cases suffering was seen as evil in some quarters of the ancient world as is seen today. For instance, just as Hippocrates believed that it came because of defects in the universe, the modern world (which has grown to be materialistic) believe that people undergo suffering because of inadequacy in their efforts. Another similarity is evident in Rene Descartes’ argument that suffering could be good. This sentiment is shared by Aeschylos, who believed that suffering helped people to acquire knowledge. Religious world has not changed extensively as they share a common believe that through perseverance in suffering they will overcome evil. However, the contrasts have also risen over suffering. For instance, modern world oversaw the separation of body from Saul, in the process, categorizing suffering with the physical body. This was not common in the ancient world. Furthermore, Leibniz managed to make a distinction between bodily and ethical evil. In this regard, suffering was classified with physical evil as opposed to the ancient times when there was no separation (Reisinho, 2012, p. 1).Advertising We will write a custom essay sample on Suffering in the ancient, Roman and Greek periods specifically for you for only $16.05 $11/page Learn More Conclusion Suffering has been understood with mixed reaction in humankind. While some sections have denied its existence, others have accepted it. On the other hand, those who have accepted it have also differed on its origin, ways of mitigation, and reason for being. However, religion has played a central role in it understandin g among other faithful. In addition, philosophers have also made steps in their discovery of its workings (Fiero, 2011, p. 15). References Fiero, G. K. (2011). The humanistic tradition, Book 1: The first civilizations and the classical legacy (6th. Ed). New York, NY: McGraw Hill. Pilch, J. (1990). How We Redress Our Suffering: An Exercise in Actualizing Biblical Texts. Web. Reisinho, E. (2012). Life Is Cruel: Pain and Suffering. Web. Steiner, R. (1906). The Origin of Suffering: Origin of Suffering, Origin of Evil, Illness and Death. Retrieved from https://wn.rsarchive.org/Lectures/GA055/English/SBC1980/19061108p01.html This essay on Suffering in the ancient, Roman and Greek periods was written and submitted by user Ayla Brown to help you with your own studies. You are free to use it for research and reference purposes in order to write your own paper; however, you must cite it accordingly. You can donate your paper here.

Investigate the erosive characteristics of targets using a centrifugal accelerator erosion tester The WritePass Journal

Investigate the erosive characteristics of targets using a centrifugal accelerator erosion tester REFERENCES Investigate the erosive characteristics of targets using a centrifugal accelerator erosion tester ABSTRACTChapter 1: Introduction1.1 Overview:1.2 Erosive wear of pneumatic conveying systems1.3 Project Aim and ObjectivesAim:Objectives:1.4 Project and its scopeCHAPTER 2 LITERATURE REVIEW2.1 Overview2.2 History of wear concept2.3 Basic concepts of erosive wear2.4 Mechanisms of wear test2.5 Factors effecting the erosive wear2.6 Test facilities and conditions2.6.1 Wear Test facilities2.6.2 Test condition for erosive wear impact2.6.3 Centrifugal accelerator erosive tester2.6.4 Glass-blast erosive wear test2.6.5 Measurement of wear 2.6.6 Measurement of solid particle velocity in erosive wear2.7 SummaryCHAPTER 3 METHODOLOGY3.1 Overview3.2 Experimental requirements3.3 Test facilities3.3.1 Centrifugal accelerator tester3.3.2 Description of tabular feeder system3.3.3 Description of Double Disc Velocity meter3.3.4 Tachometer3.3.5 Mechanical sieves3.3.6 Ultrasonic bath for clean the targets3.4 Description of test materials3.4.1 Specimen (Mild steel)3.4.2 Olivine sand3.5 Test conditions for im pacting erosion wear3.7 SummaryCHAPTER 4 Calibrations of Impact Conditions4.1 Overview4.2 Calibration of exit angle of particle jet, particle velocity and speed of the rotating disc:[S2]4.2.1 Calculation of exit angles and particle velocity4.2.2 Calculations of impact conditions of centrifugal erosion tester:4.2.3 Calibration of exit angles of particles, particle velocity, speeds of rotating disc.[S3]4.3 Design of target holders for mild steelChapter 5: Experimental procedureOverview:Procedure:5.1 overview:5.2 Experimental resultsChapter 7 Discussion of Results:6.1 Overview:6.2 Erosion rate with respect to Impact angles:6.3 Erosion rate with respect to velocity of the particle:6.4 ConclusionsCHAPTER 7 CONCLUSIONSCHAPTER 8 Future workREFERENCESRelated ABSTRACT Erosive wear is the phenomenon of removal of the surface of any component basing on different conditions due to high-speed impact of solid, liquid or gaseous particles. It is a common occurrence on most plant and machineries and manufacturing industries. The phenomenon of erosive wear has been studied for many years, and still research is going on the material-related aspects of particle impact erosion. Different laboratory testing methods were used to determine the erosion resistance of all eroded materials. In order to predict the erosive wear rate during the erosion test, some major properties such as effect of erosion parameters, effect of abrasive particle characteristics were investigated. The Aim of the project was to continue the work done by scholars and to investigate erosive characteristics of targets by using a small centrifugal accelerator erosion tester.   The present project focuses on the erosion of ductile materials particularly mild steels as these are used in pneumatic conveyor plants where some of the most severe erosion problem occurs. An experimental process was conducted with olivine sand, mild steel as hitting and target specimens to calculate the erosion rate. During the experimental process a study was made to calculate the specific wear rate and analyse the wear properties under different testing conditions. The report presented gives the detailed description of experimental process along with description of materials and tools used. Also report gives detailed analysis of relations of wear properties and rates of relations. Finally future works which could be possible are discussed in the report. Chapter 1: Introduction 1.1 Overview: Wear is a progressive loss of substance resulting from mechanical interaction between two contacting surfaces, it is a common occurrence on most plant and machineries and manufacturing industries. In 1997, a survey of wear problems and costs in UK industry indicated that a typical average cost due to wear was about 0.25 percent of company turnover [4] [5]. Wear can be abrasion, erosion, corrosion or other chemical reaction, appearance of failed surfaces (e.g. cracking, melting, phase transformation) etc But processes involving erosive wears where there is an involvement of particle size, particle velocity, angle of incidence, and particle distribution are more effective than others. 1.2 Erosive wear of pneumatic conveying systems Erosion involves the mass removed from the surface of any component at different conditions due to high-speed impact of solid particle or a liquid particle. Generally the erosive wear sizes between 5 and 500 microns by causing the particles. (W-1) [3]. Today, many engineering industrial plants are facing the situation of the erosion wear. Phenomenon of erosive wear has been studied for many years, and still research is going on the material-related aspects of particle impact erosion. There is a certain need for the analysis of wear process, before defining the exact problem. As stated earlier wear can be abrasion, erosion, corrosion or other chemical reaction, appearance of failed surfaces (e.g. cracking, melting, phase transformation etc.). The types of wear process will be able to tell what kind of testing is needed to find the wear problem. Sliding friction, erosion testing processes which involve surface fatigue can be modelled at a reduced scale. But processes involving abrasive wears, erosive wear where there is an involvement of particle size, particle velocity, angle of incidence, and particle distribution should be modelled at full scale. This can only happen with an appropriately designed test, and it will be carried out in specially designed erosion testers which involve impact of a stream of particles agai nst a test sample. In order to predict the erosive wear rate during the erosion test, some following major aspects have been investigated (3 progress) [6]. Size and shape of particle Material Properties of the target Impact conditions (Impact angle, impact velocity) Particle concentration on the target. Now a day’s Different laboratory testing methods are used to determine the erosion resistance of all eroded materials. But the main challenge lies in the prediction of correct test conditions which should be adopted during the test. Current project study will involve calibration of test conditions such as particle velocities and impact angles to the targets. The work was mostly concentrated on erosive characteristics of ductile materials used in pneumatic conveyor plants where erosive problems occur most often. As mild steel is a commonly used ductile material in conveyor plants it was chosen as the target material and centrifugal accelerator type erosion tester was used to find the wear characteristics. 1.3 Project Aim and Objectives Aim: The Aim of the project is to continue the work done by those scalars and to investigate erosive characteristics determination of mild steel targets by using a small centrifugal erosion tester.   The present project focuses on the erosion of ductile materials particularly mild steels as these are used in pneumatic conveyor plant where some of the most severe erosion problem occurs. The experiment will be carried out with some of effective erosive wear factors. Objectives: The project has been divided in to several objectives. The main objectives of this project are listed below Calibration of impact conditions on a centrifugal erosion tester Controlling the impact characteristics for pre-set test condition Determination of erosive wear for mild steel targets Relationship between erosion rates for different impact conditions. 1.4 Project and its scope   The main purpose of the project was to determine the erosive wear which is a serious problem in the pneumatic conveyors. Here in this project an attempt was made to calculate erosive wear rate in the mild steel target material using the olivine sand as the eroded material. The results obtained from the experiment can be used for minimising the erosion rate in the mild steel made pneumatic conveyors. Also the work done can be taken as a guideline for several future works in the field of erosive wear.    CHAPTER 2 LITERATURE REVIEW 2.1 Overview Ample of research has been carried out in the area of erosive wear impact on plant and machineries and manufacturing industries. The theoretical concepts obtained from different references such as journals, websites, papers and books which are directly or indirectly related to the project are presented in this chapter. 2.2 History of wear concept Erosive Wear is the concept which is not new to the manufacturing industry, it was first proposed in 17th century. Till 18th century until Osborne Reynolds paper on hydrodynamic lubrication it was not well known in manufacturing industry. In the paper author explained the causes of wear and need for lubrication for the first time. Gradual progress was made from 18th century and now days it has emerged as important factor in any manufacturing industry. 2.3 Basic concepts of erosive wear Removal of material from the surface of the solid body is known as wear. Wear may combine effects of various physical and chemical processing preceding the friction between two contracting materials. obtained result was micro-cutting, micro-ploughing,  Plastic deformation, cracking,  fracture,  welding, melting, chemical interaction(w-2)[11]. Before the start of project it is necessary to know the all basic concepts of wear. Definition of wear coefficient K. (Lb-2) [12]K= Where V=volume worn away L= total sliding distance W=applied load Erosive wear occur due to the impact of number of small particles on the surface of the any mechanical object. Generally erosive wear is caused by the particles of sizes between 5 and 500 microns. Surfaces are impacted by continuous stream of hard particles which is known as particle erosion (11) [3]. One of such major place where erosion occurs is pneumatic conveyors, which may result in punctuation of conveyor bends or dust problem if the bends are penetrated. The main effects of the erosive wear are (2) [13]. Dimensional changes Leakage Lower efficiency Generated particles contribute more wear Erosive wear resistance cannot be estimated only by hardness and characterizing resistance to  Ã‚   penetration. The wear resistance of hard material with equal hardness level can be attributed to their resistance fracture (8) [14]. There are two types of wear which are main reasons for erosion. The first one is due to the repeated deformation during the collision and the other one is due to the cutting action of the free moving particles. The rate of erosion depends on the particle velocity which results in the plastically formed concavity of similar radius of curvature to that of the particle (2)[13]. Repeated deformation during the collision: This type of erosion occurs in the systems in which particles moves at high speeds for example pneumatic fluid bed systems, air mills etc. where the particles move free at high speed and impact on the solid which results in the wear (2)[13].The formula for deformation wear is Where Wd= Units volume loss M= Total mass of impinging particles V= Particle velocity ÃŽ ±= Impact angle K= Maximum particle velocity at which the collision still is purely elastic and ÃŽ µ= the energy needed to remove a unit volume of material from the body by deformation wear. Cutting action of the free moving particles: This type of wear is occurred due to the particle that impinges the component at an acute angle and due to this there is scratching of material from the surface of the component. This scratching of the material is highly influenced by the velocity and the impact angle of the particle (2)[13]. 2.4 Mechanisms of wear test Wear is occurred by mechanical or chemical reactions generally accelerated by friction heating. There are six main wear phenomena which explain only removal of material from the solid surfaces (16) [15]. In many cases, wear is initiated by one of these mechanisms and it may proceed by other wear mechanism, there by complicating failure analysis. Particle contamination can damage systems by causing a variety of types of wear (15) [12]. The following table shows the primary cause of wear for each mechanism (1) [16]. Type of mechanism Primary cause Abrasive wear Particle between adjacent moving surface Adhesive wear Particle and high fluid velocity Fatigue wear Surface to surface contact (loss of oil film) Corrosive wear Particle damaged surface subjected to repeated stress Erosive wear Water or chemical Table 2.1: Different types of wear mechanisms. (1)[16] Finnie in his work Observations of the erosion of ductile metals has made an attempt to clearly discuss the factors affecting the erosion in ductile metals. Also Gwidon W. Stachowiak, Andrew W. Batchelor, GrazynaStachowiak (2004) in their journal Experimental methods in Tribology discussed the mechanism of erosion of ductile metals analytically and experimentally. The analysis was carried out by writing the equation of motion of a single particle impaction on the surfaces, volume for the same was then calculated using the trajectory of particles [18]. Such type of approaches was obviously unsuitable for brittle materials. In the experiment the particle velocity on the surface of the ductile metals were obtained by using high speed double flash light source. The authors mainly concentrated on the calculation of single particle of different sizes and at different angles with which he then calculated for whole of the volume of particles. The authors also explained about the drawbacks th at they came across during the experiment and mentioned about the most unsatisfactory feature of his analysis. It underestimates the weight loss at large angles and, in particular, predicts no erosion at 90 °, and explained the three effects which cause the relative erosion at high angles to be greater than that predicted by the sample theory (9)[17]. 2.5 Factors effecting the erosive wear The numbers of factors which significantly affect the rate of erosive wear were discussed by Dr.Dmitri Kopeliovich in his work Mechanisms of wear in 2009.According to him the factors are (12)[11] Impingement angle: the angle at which a particle hits the surface is very important to erosive wear rate. By the experience it was found that the wear rate was high at an angle of 30 ° for ductile material and 90 ° angle for brittle materials. Impact speed: high speed particles impacts cause more damage than low speed collisions. Particle properties: particle properties were more important in erosive wear phenomenon, sharp and hard particles causes more wear rate. Temperature: High temperatures cause high erosive wear because increase in softness of material in high temperatures Particle flux rate: Particle flux rate is the mass of particles hitting an area of surface per unit of time, which can vary greatly from 100 kg/m^2/s to 10,000 kg/m^2/s. 2.6 Test facilities and conditions 2.6.1 Wear Test facilities The national laboratory in the UK identified over 400 wear testing standards all over the world and American society of lubrication engineers indentified 300 tests that were used in various test laboratories in year of 1973. From these tests some type of tests have slight variation on others, less than 100number of tests are useful to find out the wear problems (15)[12]. As early as Mr. Neale was carried out a survey on wear in 1997 as the result in his survey seven types of wear mechanism were identified, most significant wears were abrasive, erosive and adhesive wear. More than one test method is justified for a particular wear type and more than ten test methods are justified to meet industrial need for seven types of methods (14)[5].There are three major types of erosion testing devices that are used throughout the world for quantifying particle impact erosion against a solid surface (10)[18]. 2.6.2 Test condition for erosive wear impact One of the important tasks of the project was to identify the ideal testing conditions. A journal by B.G Mellor in Surface coatings for protection against wear gives the brief idea of various testing standards. According to Mellor the main equipment that is required to find the erosive wear of the pneumatic bed is the centrifugal accelerator erosion tester. Here in the experiment the different test conditions like using different velocities at different impinging angles are used to find the erosive wear of the component. The investigation is mainly focused on the effect of the particle concentration, effect of progression of wear and the effect of bend radius (3) [19]. The pneumatic conveyor test rig should also be inspected prior to the experiment. The equipment should be set to the conditions that would exactly suit the experiment. Hence, the rotational speed of the screw feeder, the blow tank pressure and the mass flow rate of the air supplied to the conveying pipe all should be adjusted to give a positive experimental result (4)[20].   As mentioned the test rig material is the mild steel on which the experiment is to be performed. The material that is to be used in the experiment which is to be impinged on the mild steel component is the olivine sand abrasives. Olivine sand consists of 98.5% (Mg,Fe)2SiO4, with the balance being made up of traces of metallic oxides. The particles density of the abrasive material should be found out prior to the experiment. The grain size should also be measured and found before the experiment (3)[19]. 2.6.3 Centrifugal accelerator erosive tester The test equipment that is to be used for the determination of the erosive wear for mild steel impacted by olivine sand is the centrifugal accelerator erosion tester. The schematic figure of the centrifugal accelerator erosion tester is shown below (4)[20]. Figure 2.1: Schematic of the centrifugal accelerator type erosion tester (4)[20]. The centrifugal accelerator erosion tester is the testing equipment that is to be used in the experiment in the laboratory. The main parts of the centrifugal erosion tester are feeder, an accelerating rotating disc and a target holding system. The abrasive olivine sand is fed into the central hole of the rotating disc and is accelerated through the several radial ceramic tubes by the centrifugal force and ejected from the end of the tubes. The specimen targets are set for the reorientation relative to the direction of parallel flow by the disc on holders. The edges and back face of the specimens are protected from particle impact to prevent unwanted erosion. The target holder is the main equipment that is used for the change of angle for the particles that to be feed into the system. There are many experiments performed using the same equipment by many researchers which would help the present work with their papers. They clearly explained about the working procedure of the experiment and the methodology and also the result which would be a great reference for the present piece of work (5)[21]. 2.6.4 Glass-blast erosive wear test This test used for determined the wear factors .the glass blast test is consist of carbide nozzle 90mm in length with inter diameter 3mm and it having air injection for particle acceleration. A screw feeder mounted to form a loss in weight, this feeder fed the abrasive into the injector housing. And the object was placed on the adjustable table to control impact angles on the object. The author T.Deng was compared the wear factors using the two wear test and compared the results (6) [22]. The figure 2.2 show below was glass-blast erosive wear test. Figure 2.2:   Glass blast erosive wear test (6)[22] 2.6.5 Measurement of wear The measurement of wear is partly determined by the change of mass occurred in the object. A journal by Gwidon W. Stachowiak, Andrew W. Batchelor, GrazynaStachowiak in Experimental methods gave the brief idea about measurement of wear.   Another problem in the experiment of wear is loss of data when wear is measured over a series of intervals as opposed to continuous monitoring and this monitor shows all worn loss on the object figure 2.3.    Figure2.3: Loss of information when continues wear recording is substituted by periodic measurement (17)[23]. At present there are methods of measuring wear: Detection of change in mass. Measurement of reduction in dimension of a worn specimen. Profilometry of the worn specimen. 2.6.6 Measurement of solid particle velocity in erosive wear Authors A. W. Ruff and L. K. Ives in their paper explained about measurement of solid particle velocity in erosive wear that is being performed in their experiment in the laboratory. Measuring of solid particle velocity is mostly depends on the best erosive testing equipments. Here they have performed the experiment using three different erosion testing apparatus, and explained the working procedure of each of the three different apparatus used. The motion of velocity of particles was determined by high speed photo graphics methods. Also they have shown methods of increasing and decreasing the velocity of particles through motors and transmitted them on transducer output which can be viewed directly on an oscilloscope. As the project is based on experiment the paper would be of great use because the experimental procedure can be useful in many ways (7)[9]. 2.7 Summary The chapter gave detailed literature review of the concept of erosion and its developments over the years. Literature review was very much useful for the proper understanding of the topic and gaps in research. Based on these gaps in research the author proceeded further in project work and the next chapter gives detailed methodologies, equipments and tools used during project work. CHAPTER 3 METHODOLOGY 3.1 Overview This chapter explains about the different testing methods and tools used during the experimental process. Also a brief description of materials and material handling equipment is given. 3.2 Experimental requirements olivine sand was prepared to required sizes: Due to vast availability of olivine sand in the nature it is been preferred in the present project. With the use of sieving machine olivine sand was prepared to required sizes ranging from 45-425 µm. impact velocity and angle were calibrated by double disc velocity meter: The double disc velocity meter was used for calibration of impact angles and impact velocities. The calibration results were used for calculating the erosion rate of the mild steel target at proposed conditions. Setting up of right test conditions: To satisfy the proposed test conditions the correct setup of the experiment was required. The setup process would include setting up the position of the target angle, rotating speed of the accelerating rotating disc and feeding rate of the olivine sand. The erosion characteristics of mild steel were determined at certain conditions: Most of the pneumatic conveyers are designed by specific characteristics conditions , based on this characteristics condition have been choose some specific conditions such as an impact angles 20 °,30 °,45 ° and 90 °Ã‚  Ã‚   and velocity 20,30 and 40 m/sec during this experiment . The main intention was to finding impact angles, impact velocities and size of the material were to determine the erosion rate. Determination of specific erosion rate on mild steel: The specific erosion rates of mild steel target were calculated at different conditions by changing the impact angles and impact velocities, the results were analysed. The highest erosion rate and the least erosion rate of the target were calculated. These results were useful for the predicted models. 3.3 Test facilities There were number of tools used for analysing the test during the experiment which was described below. 3.3.1 Centrifugal accelerator tester Erosion wear test apparatus built by T.deng at the wolfson centre was available for this wear test. Centrifugal accelerator tester which is illustrated in figure 3.1 below consists of a feeder, an accelerator rotation disc and target holding systems. There were two types of feeders to feed the materials into the rotating disc which were vibratory feeder and conical feeder. Conical feeder was used for this present project. The target particles continuously fed to the centre hole of the accelerator rotating disc through special type of funnel, and then from the feeder they travel outwards along the radial tubes in the rotating disk. Material leaves disc at the periphery with tangential velocity equal to disc velocity. Targets are mounted at the points surrounding the periphery of the disc and the specimens are exposed to a series of eroded streams particles from the radial tubes of the rotating disc. Figure 3.2 schematical diagram of centrifugal accelerator tester:   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Figure 3.1: Centrifugal accelerator type erosion tester This method is more advantageous over the gas jet method and well suited to perform the screening tests on many different materials. The specimens were mounted on the holding system which rotates slowly around the accelerator rotating disc but it rotates only in one direction, to eliminate any possible bias associated with specific specimen locations. The maximum numbers of specimens per test have ranged to 30 in different design of rigs. [25] Accelerator rotating disc is one of the most important parts of the centrifugal accelerator tester. Usually the rotating disc diameter varies between 200 and 600 mm. The apparatus shown in figure 3.1 has a disc of 240 mm in diameter and it contains six radial alumina ceramic tubes with an internal bore diameter of 2.6 mm. The erosion centre was placed on rotating disc of 0.24m diameter [25]. The disc was attached to an infinitely variable inverter controlled motor that was driven by V- shape belt drive. The motor requires 220-240 voltage and which has maximum of 2850 revolution per minute. 3.3.2 Description of tabular feeder system In order to obtain a constant mass flow rate of the abrasive particle, a tabular feeder is used to feed the abrasive material into conveyers or into the erosion test rig and serves as an auxiliary machine in coal washing, electric power, sintering plant and building industries [24]. Tabular feeder consist two main parts. 1)   Hopper 2)   Rotating control disc Hopper acts as storage for olivine sand before feeding into the accelerator disc, rotating control disc controls flow rate of material is required. The speed of the rotating disc can be altered using this speed control unit as a result the material flow will change according to the speed of the rotating disc. Figure 3.2 shows the laboratory tabular feeder used for the project work. Calibration of the tabular feeder was achieved by measuring the flow rate of mass of materials. Figure 3.2: Tabular feeder [U1] 3.3.3 Description of Double Disc Velocity meter There are two types of instruments which were used to measure the particle velocity vector in an erosion tester, they are optoelectric velocity meter and laser Doppler anemometer (k89) [10]. The accuracy of the particle velocity measure was low while using optoelectric velocity meter in centrifugal erosion tester. Therefore, a static form of the double–disc velocity meter and displaced wear scar method (R75)[9] were used for calibration test of the particle velocity vector. Static form of double disc velocity meter is used to measure the particle velocity vector and direction of particle travel. The slot on the double disc velocity meter from which continuous flow of eroded particle travels and hits the surface of the target forms a scar on target material. The exit angle of the actual particle jet can be calculated by the following equation. A schematic diagram of double disc velocity meter is shown in figure 3.3. Figure 3.3: Double disc velocity meter 3.3.4 Tachometer Tachometer is a mechanical instrument used to measure the speed of rotating devices. Here in the present experiment it is used for measuring the speed of the accelerating rotating disc. It has the digital display which when placed against the rotating device shows the speed in rpm. The figure of tachometer is shown below. Figure 3.4: Tachometer 3.3.5 Mechanical sieves Sieving is one of the oldest and well-known methods for particle size measurement. Sieve test is a procedure to differentiate the fine material from the course material with the help of a nested column of sieves with wire mesh cloth. Required material is poured into the top sieve which has largest screen openings, each sieve openings in the column are arranged in order of decreasing size, from top to bottom, where it is collected at the base, which is called receiver. The sieve shakes the column, for fixed amount of time, depending on amount of material poured. After the material is finished amount of sand on each sieve is weighed. The weight of sample of each sieve is then divided by the total weight to give a percentage retained in each sieves. Figure 3.5 shows BS Sieves with sieve shaker machine. % Retained =   Ãƒâ€"100 % Where W sieve is mass of retained in sieve W total is the total mass retained in all sieves. Figure 3.5: Mechanical sieves on sieve shaker 3.3.6 Ultrasonic bath for clean the targets An ultrasonic machine is cleaning equipment used for delicate items which uses ultrasound (usually from20-400 kHz) and the appropriate cleaning solvent (sometimes ordinary tap water). This machine can only be used with water but solvent which gives a better cleaning option is always advised to clean the object. These machines are mostly used for cleaning jewellery, lenses and other optical parts, surgical instruments. Ultrasonic machine uses high frequency sound waves to agitate in an aqueous or organic compound. Water is used for normal cleaning of the object where as the solvent is used for more effective cleaning. Figure 3.6: Ultrasonic Targets Cleaner 3.4 Description of test materials 3.4.1 Specimen (Mild steel) Mild steel typically means soft, unhardened steel with low carbon content. Mild steel is the type of steel that contains iron as well as little amount of other elements i.e. 0.18-0.23%Carbon, 0.30-0.60%Manganese, 0.30% Silicon, 0.040% Phosphorous and 0.50% Sulphur. Cheap availability, high stiffness and magnetic property are some of the user friendly characteristics for the vast application of mild steel. Other specifications of mild steel are: Density of mild steel =7.85 g/cm3 (0.284 lb/in3) Young’s modulus = 210,000Mpa (30,000,000psi) Mild steel was taken in 2.5Ãâ€"25Ãâ€"26 mm square specimens and mass of each specimen was measured as approximately 13.34 to 14.90 grams. Figure 3.7: Mild steel target 3.4.2 Olivine sand Olivine sand is one of the most common and easily available minerals in the earth, It has less amount of thermal dilation and is composition of magnesium and iron ortho silicate with chemical formula (Mg,Fe)2SiO4. The density of olivine sand is 3.28 gm/cm3, melting point up to ~1760 deg. C and the crystals present are angular with sharp edges [29] and the product is hard, dense and heavy in nature. It is an abrasive media for sand blasting and water jet cutting services. The main uses of olivine sand are iron ore processing, foundry sands, abrasives, agriculture etc. Chemical Specification of olivine sand [30]: Products Specification MgO 42-47 % SiO2 35-42% Fe2O3 10-13% CaO 2-2.5 % LOI 1.5% Max    Figure 3.8: various size of olivine sand (45~425  µm) 3.5 Test conditions for impacting erosion wear The prominent parameters and their effect on erosion are as follows: 1) Impact angle Impact angle is defined as the angle between the target surface and the direction of striking the solid particle. The variation of erosion wear with the impact angle depends on the characteristics of the target surface material namely brittle or ductile type. 2) Velocity of solid particles Velocity of solid particle strongly impacts the erosive wear. As particle velocity increases there is significant increase in erosion rate. The erosion rate is generally related to the particle velocity using power law relationship in which the power index for velocity varies in the range of 2-4. 3) Particle size and shape of test materials Particle size and shape is also one of the prominent parameter, which impact erosion wear. Many investigators have considered solid particle size important to erosion. The erosive wear increases with increase in particle size according to power law relationship. The effect of particle shape on the erosion is not very well established due to difficulties in defining the different shape features. Generally roundness factor is taken into consideration. If roundness factor is one then the particles are perfectly spheres and a lower values show the particle angularity. Analysis of hitting particle (Olivine Sand) Pneumatic conveyors are mainly used to transport the powdered materials with high speed and various angles. Project work was mainly based on wear erosion of ductile materials in pneumatic conveyors which is caused by powdered particles, hence Olivine sand was chosen as hitting material. Olivine sand is Magnesium Iron silicate which is one of the most common materials found on the earth, Because of its availability and low cost it was chosen in the work, a detailed description of olivine sand was given in section 3.2. One of the important factors in erosion rate of the target material is size of the particle. Hence measuring of size of the olivine sand was the first experimental work which has been carried out. The size of the sand was measured by using BS Sieves; the description of BS sieves was given earlier in the chapter. Steps involved in analysis of sand are as follows: 300 grams of olivine sand was taken and dried before use. The sand was poured through different sizes of BS Sieves which vary from 45  µm to 425  µm.   Ten minutes of vibration with amplitude of 7 Hertz were taken as the standard measurements for the apparatus.   The vibrator which was connected to sieves vibrates whole apparatus then sand follows downward path on the apparatus leaving behind different sizes of grains in each sieve. Amount of Different sizes of sand left behind in each sieve was measured using electronic weighing machine. Calculations related to Olivine sand are as follows: Percentage of weight retained in each sieve is given by dividing the weight of sand in each sieve by total weight of sand. % retained = (W sieves / W total) Ãâ€"100 % Where W sieve is mass of sand retained in sieve W total is the total mass retained in all sieves. Amount of sand left behind in each sieve and percentages of remaining amount of sand were calculated and tabulated. Tabular column was given in appendix 3.1 A graph was plotted with cumulative percentage of total mass of sand retained on Y axis and sieves size on X axis. This graph gives the average size of particle which was to hit the target. Figure 4.1: Cumulative graph for percentage mass of sand and sieve size It can be seen from the graph that a centre line is cutting the cumulative percentage weights of the sand. The point where the line cuts the graph is the average weight of the particle. The average size of the particle was calculated as ≈ 144 µm from the above graph and shape of olivine sand was angular. After size analysis of material, the next stage of the experimental procedure was calibration of impact velocity and angle of the particle .In case of the centrifugal accelerator, the particle velocity is dependent on the rotation velocity of the rotating disc. The range of particle impingement over the surface of a target varies due to the geometry of this type of erosion tester and need to be accounted for. Therefore, some calibrations are necessary to be carried out before the test work starts which include measurement of particle velocity and calibration of the abrasive feeders. 4) Particle concentration for erosive tests Concentration is amount of solid particles by weight or by volume in the fluid. As concentration of particle increases more particles strike the surface of impeller which increase the erosion rate, the concentration of slurries can vary from 2% to 50% depending upon the type of slurry. However, at very high concentrations particle interaction increases and this decreases the striking velocity of particle on the surface. 3.7 Summary This chapter can be considered as the backbone of project work as all the methodologies, description of working equipment, testing conditions and analysis of testing materials were discussed in the chapter. The following chapter discusses about the calibrations of impact angles which is most important in finding the exact test conditions. CHAPTER 4 Calibrations of Impact Conditions 4.1 Overview This chapter gives detailed description of work done during the project work. All the experimental works, results obtained from those experiments, analysis of the results have been discussed the chapter. 4.2 Calibration of exit angle of particle jet, particle velocity and speed of the rotating disc:[S2] The second and most important phase of the experimental work was the calibration of exit angle of the particle, velocity of particle and speed of the accelerator rotating disc. Before calculating erosion rate of target material it is necessary to know the speed of accelerator rotating disc and exit angle of hitting particle at given testing conditions. These can be calculated by calibrating the results obtained after carrying out the experiment with different standard speeds of accelerator rotating disc and various impact angles of hitting particles of the target material. Certain testing conditions were suggested for the experiment which are: Impact angles of the hitting particles at 20 °, 30 °, 45 °, 90 ° of the target material Impact Velocities of hitting particle: 20m/s, 30m/s, 40m/s This stage of experiment was sub divided in different stages: 4.2.1 Calculation of exit angles and particle velocity The exit angle and velocity of the particle was calculated by hitting the target surface with olivine sand. An electric circuit board was taken as target material for this calibration test. The exposed surface of the target was coated blue colour for a better view of particle impact and then it was placed in double disc velocity meter. A detailed description of double disc velocity meter was given in chapter 3. A total of six double disc velocity meters were used for three different angles for more accurate calibrations. The double disc velocity meters were placed in a work holding system where the normal target holders are placed and with desired angles which are 30, 45, 60 degrees respectively. The figure 4.2 shows the work holding system with double disc velocity meters. Figure4.2: Double disc velocity meter on target holding system Figure 4.5:detailed schematic figure of double disk velocity meter with target Different stages of the experimental procedure are described below. Velocity of accelerator rotating disc was fixed to 1500 rpm with the help of tachometer. There was a speed controller for increasing and decreasing the rotating disc speed to obtain desired speed. The double disc velocity meter was located at the position where the normal specimen target holders stand and rotated to a given angle ÆŸr, with respect to the centre of the rotating disc. 500gms of olivine sand was manually fed into the centre of accelerator rotating disc with the help of conical feeder. From the centre of rotating disc the eroded particles (olivine sand) was equally distributed into the six ceramic tubes. By centrifugal force Olivine sand is forced towards target specimens through alumina ceramic tubes. The continuous flow of sand hits the targets with certain angle which is the exit angle of particle (K) forming the impact on surface of the target. The specimen was then removed and cleaned and then photo scanned for further calculations of exit angle and particle velocity. Figures 4.3 show the scanned photo of two test specimen for 30 degrees impact angle on target surface. Figure 4.3: The scan photo of two test specimen for 30 degrees impact angle on target surface. Figures related to other angles and other rotating speeds are shown in appendix 4.1. Exit angle of the particle was calculated by using the following figure. Figure 4.4 geometry of the double disc velocity meter for measuring the particle velocity vector and particle exit angle at the time of testing 4.2.2 Calculations of impact conditions of centrifugal erosion tester: Using photo scanner which can improve the accuracy of measurement from 0.5mm up to 0.01mm, the exit angle of the actual particle jet can be calculated by the following equations, K=cos-1 [sin (60 °-ÃŽ ±)/r Ãâ€" (r+s)] for 30 ° angle K=cos-1 [sin (45 °+ÃŽ ±)/r Ãâ€" (r+s)] for 45 ° angle K=cos-1 [sin (30 °+ÃŽ ±)/r Ãâ€" (r+s)] for 60 ° angle Where, K= exit angle, r= radius of the rotating disc, s= distance between slot and edge of accelerator disc, ÃŽ ±=angle between target centre and particle jet. 1)  Ã‚  1500 rpm -30 °- 1 target From the formula stated above K=cos-1 [sin (60 °-ÃŽ ±)/r Ãâ€" (r+s)] From the reference of figure 4.4 the following values were obtained x= 3.98, y=11.55, r=120mm, s=18.65, ÃŽ ±=19.01 °   k= cos-1 0.723 K=40.73 ° Where X= distance from impact centre to target centre Y= distance from slot to target r= rotating disc radius s=distance from rotating disc to slot centre ÃŽ ± = angle of target holder 2)  Ã‚  1500 rpm -30 °- 2 target   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   From the formula stated above K=cos-1 [sin (60 °-ÃŽ ±)/r Ãâ€" (r+s)] From the figure the values were obtained x= 4.15, y=11.95, r=120mm, s=18.65, ÃŽ ±=19.15 °   Cos k= 0.730 K=40.91 ° The calculations for the exit angles of the particle jet at 45, 60 degrees at a speed of 1500 rpm are shown in appendix 4.2. The experiment was repeated with different speeds of accelerator disc which are 2000 and 2500 rpm respectively. The calculations are shown in appendix 4.2. The quantity of sand was decreased with increasing speeds of accelerator disc, for accurate impact on the surface. Exit angle for each speed of rotation disc was calculated by the formula Exit angle K = Where k1, k2, k3, k4, k5, k6 are exit angles of particle jet. And all the exit angles were tabulated below Position of the Target angle (deg) Exit angles of Particle jet (deg) Accelerator disc speed (rpm) 1500 2000 2500 30 ° Target 1 (k1) 40.73 ° 40.68 ° 42.68 ° Target 2 (k2) 40.91 ° 41.23 ° 41.29 ° 45 ° Target3 (k3) 32.43 ° 32.50 ° 39.42 ° Target4 (k4) 33.55 ° 32.81 ° 40.39 ° 60 ° Target5 (k5) 37.79 ° 37.69 ° 38.53 ° Target6 (k6) 35.78 ° 36.43 ° 37.01 ° Exit angle (K) 36.86 ° 36.905 ° 39.88 ° Table 4.2: Exit angles for various double-disc velocity meters at different angles and speeds The next step was to calculate the particle velocity which was calculated by using the following methodology: Figure 4.5: calibration of the particle velocity For 1500RPM Exit angle K=36.865 ° from above tabular column. Tangent angle (VÃŽ ¸) = ωr Where ω is speed of the accelerator rotating disc r is radius of radius of accelerator rotating disc VÃŽ ¸=18.84m/sec From the Figure 3.4 Cos (K) =VÃŽ ¸/VP Where VP is Particle Velocity Cos (36.865 °) = 18.84/VP VP=23.55m/sec In the similar way particle velocity at different rpm was calculated .the calculation part are shown in appendix 4.3and the velocities are: Particle velocity for 2000 RPM is 31.43m/sec Particle velocity for 2500 RPM is 40.94m/sec. 4.2.3 Calibration of exit angles of particles, particle velocity, speeds of rotating disc.[S3] The next and most important stage of the experiment was calibration of Exit angles of particles, particle velocity, and speed of the rotation disc. A graph was plotted with the help of obtained exit angles; particle velocity for standard conditions (disc velocity 1500, 2000, 2500 rpms, and target angles 30 45 60 degrees) is shown in figure 4.6. Figure4.6: Calibration of exit angles of particles, particle velocity, speeds of rotating disc.[S4]   Calculation of speed of rotating discs, exit angle from the calibration, at proposed impact velocities. With the help of graph, the values of rotating disc speed, exit angles of the particles were found for the given testing conditions. The values of particle exit angle (K) and rotating disc speed are given in the tabular column below. Proposed impact velocities (m/sec) Particle exit angle K (degree) Rotating disc speed (rpm) 20 36.5 1280 30 36.9 1909 40 39.9 2442 Table4.3: values of exit angle and rotating disc speed at impact velocities 20, 30, 40 m/sec. 4.3 Design of target holders for mild steel Target holder is an important device in the experiment which was used to place the target in different required positions. Hence designing of target holders was an important task for any erosive experiment. These target holders contain screws for tightening the specimen in correct position to avoid slips when the test was running. As discussed earlier in chapter 3 mild steel material was used as a target with 25mm square in size and approximately each target was 14.34grams mass. The target was held in a jig which protects the edges and back face of the test specimen. The jig with test specimen was fitted in to a target holder which would be capable of supporting the velocities of hitting particle jets, and can be tilted to different angles required for the test. Generally, there were three types of target holders used to find out the erosion rate of the target, but in the present project the horizontal target holders are used to hold the target specimen to find out the erosion rate. Here the suggested four different impact angle targets such as 20á ´ ¼, 30o, 45o and 90o were taken. For each angle two target holders are taken and the totals of 8 target holders were located on the target holding system for this experiment. The figure 4.1 shows the target in the target holder. As the experiment was conducted at four different impact angles which are 20o, 30, 45 and 90 which are shown in the figure 4.2, 4.3, 4.4, 4.5 schematically. Figure 4.1: target holder    Summary In the chapter discussed the calibrations working procedure for find out the exit   angles and velocities by   related formulas and calculation   which is most important in finding the exact test conditions. Chapter 5: Experimental procedure Overview: The chapter discusses about the experimental procedures which were carried out during the project work. A flow chart is also presented in the chapter which shows the detailed working procedure. Typical photographs of the target surface eroded at different test condition were shown in this chapter. Procedure: Finally the main part of project work was carried out, calculation of erosive wear under specified conditions. From above section, with the help of graph and tabular column it was found that for given testing conditions of particle velocity 20 m/s, 30 m/s and 40 m/s the accelerator speeds are 1280 rpm, 1909 rpm and 2442 rpm, similarly the exit angles are 36.5, 36.9 and 39.9 degrees respectively. The first stage of experiment was carried out for 20 m/s particle velocity and later it is repeated for other particle velocities. But Different quantity of sand was taken when increasing speeds of accelerator disc. Steps involved in the experiment are followed: The apparatus was setup before the experiment. The targets were arranged on target holding system in horizontal position with the impact angle of 20 °, 30 °, 45 °, and 90 °. For more accurate values a total of eight targets were used two for each impact angle position. Target specimens were punched with numbers A1 to A8 for clear identification after the experiment. Before fixing the target materials on holding system they were cleaned with ultrasonic bath using isopropyl alcohol. A detailed description of Ultra sonic bath was given in section 3.3.6. Once the targets cleaned they were weighed using electronic weighing machine which has an accuracy of about 0.1mg. For more accuracy three readings were noted and an average of three was taken as the original weight of target specimen. In the next step the target was arranged at an exit angle of 36.50 and with a centrifugal accelerator disc speed fixed to 1280 rpm and at a particle speed of 20 m/s. The apparatus was all set for carrying out the experiment. Once the apparatus was set up the olivine sand was poured through the tabular feeder for experiment.   But at this instance the issue was how much sand per specific time the feeder should pour. The calibration of tabular feeder gives the rate of feeding for sand. After the calibration was completed the rate of feed should be set for this particular testing condition. This completes all the required set up and requirements for the experiment. After all setup was completed experimental process was started by pouring the sand at a rate of 66.6 g/min. The feeder continuously poured the sand which was approximately 2 Kg in to rotating disc centre for about 30 minutes and the accelerator disc dispatched the sand on to targets. Sand particles which were in line with target materials hit the target and eroded the material from the target. After finish the test, target materials were removed from the target holders. They were again cleaned with ultrasonic bath using isopropyl alcohol also dried and weighed using the electronic balance. The experiment was repeated six times for more accurate results and results were tabulated. Results obtained during the experimental procedure are discussed in the next chapter. A flow chart of experimental procedure is given below: Figure: flow chart describing the experimental procedure The above experimental procedure of the flow chart was used for the other impact condition. The figure 5.2 shows target specimen for 20 m/sec velocity after the test.   30 and 40 m/sec. Velocities figures was shown in the appendix 5.1 Figure5.2: Above figures shows the mild steel specimen after the impact of particles on it at 20o, 30o, 45o and 90o angles and impact velocity 20 m/sec.   Summary Chapter provided the detailed description of experiment procedure for erosive wear test using centrifugal accelerator tester. And also the working procedure flow chart.    Chapter 6 Experimental Results 5.1 overview: This chapter gives the results obtained during the experimental procedure. Detailed tabular columns of results, graphical representations are presented in the report. 5.2 Experimental results Table 4.2 gives the detailed weights of target material before and after the experiment. After measuring target material weights it was time to calculate the amount of eroded material. The amount of eroded material is calculated by deducting the weight of test specimen after the impact of olivine sand from the weight before impact. The specific erosion rate which is amount of material eroded per kilogram of sand was found using a software program designed to calculate the specific erosion rate. The tabular column 4.3 gives the detailed results of amount of eroded material for different angles and weights. Targets    Angle of Targets sand used No. Impact 2 kg 4kg 6kg 8kg 10kg 12kg   remove material (g/kg) specific E(g/kg) A1 20o 0.0003 0.0008 0.0012 0.0018 0.0023 0.0028 0.000233 0.0057 20 ° 0.0057 A2 20o 0.0004 0.0011 0.0016 0.0023 0.0027 0.0037 0.000308 0.0075 20 ° 0.0075 A3 30o 0.0005 0.0009 0.0014 0.0022 0.0027 0.0034 0.000283 0.0069 30 ° 0.0069 A4 30o 0.0004 0.0006 0.0012 0.0020 0.0026 0.0032 0.000267 0.0065 30 ° 0.0065 A5 45o 0.0002 0.0003 0.0011 0.0019 0.0022 0.0030 0.000250 0.0061 45 ° 0.0061 A6 45o 0.0004 0.0007 0.0009 0.0014 0.0018 0.0027 0.000225 0.0055 45 ° 0.0055 A7 90o 0.0004 0.0005 0.0006 0.0008 0.0009 0.0013 0.000108 0.0026 90 ° 0.0026 A8 90o 0.0004 0.0005 0.0006 0.0007 0.0008 0.0012 0.000100 0.0024 90 ° 0.0024 A graph was plotted between the amount of material eroded on Y- axis and amount of sand used on X axis which shows a gradual increase in the material eroded with the increase in amount of sand. Figure : This ends the experimental process which was carried out for the given testing conditions. After the experimental procedure the following values of erosion rate were obtained. Impact angle Specific erosion rate 20 0.0057 20 0.0075 30 0.0069 30 0.0065 45 0.0061 45 0.0055 90 0.0026 90 0.0024 The experiment was again repeated for other testing conditions, the amount of sand used will vary with respect to testing conditions. For   Impact velocity 30m/s Accelerator disc speed 1909 rpm Exit angle 36.90 The results were found as Impact Angle Material Removed Specific Erosion Rate 20 0.000922 0.0225 20 0.001011 0.0246 30 0.001089 0.0265 30 0.001122 0.0274 45 0.001022 0.0249 45 0.001022 0.0249 90 0.000500 0.0122 90 0.000533 0.0130 For Impact velocity of 40m/s Accelerometer speed of 2442 rpm Exit angle of 39.9 degrees the results were found as remove material (g/kg) Specific E (g/kg) 0.001900 0.0483 20 0.001867 0.0474 20 0.001983 0.0504 30 0.002133 0.0542 30 0.002017 0.0513 45 0.002067 0.0525 45 0.001133 0.0288 90 0.001133 0.0288 90 Chapter 7 Discussion of Results: 6.1 Overview: This chapter gives the detailed discussion of results obtained during the experimental process. Variation of erosive rate with respect to various characteristics is discussed in the chapter. From the experiments it was found that erosion rate of the material from test specimen is mainly dependent on two factors; Impact angle of the particle Velocity of the particle 6.2 Erosion rate with respect to Impact angles: A Graph was plotted between impact angles on X axis and Specific erosion rate on Y axis which was shown in figure 5.4.2. This graph has an increase in erosion rate from 20 degrees to 30 degrees of impact angle of target material. This increase was because decline in erosion rate along with increase in impact angle. It can be understood from the graph that as the impact angle of particle increases the erosion rate gradually decreases. This decline in erosion rate is because the number of sand particles hitting target decreases with increase in angle. Figure : 6.3 Erosion rate with respect to velocity of the particle: From the tabular columns 3.4 and 3.5 and 3.6 it can be noted that as the velocity of particle increases the rate of erosion increases. The reason behind this graph is high velocities particles erodes more material. 6.4 Conclusions CHAPTER 7 CONCLUSIONS The project had four objectives to be delivered and which were successfully achieved. The main objective of the project was to investigate the rate of erosion for mild steel targets under specific testing conditions. After conducting series of experiments with olivine sand and mild steel targets, erosion rate for particle speed of 20 m/s, 30 m/s and 40 m/s was calculated. From all the results obtained graphs were plotted to understand the nature of rate of erosion of particles. The graph suggests that rate of erosion increases with increase of particle speed on the target material. Also other graphs plotted between the rates of erosion and impact angle of target suggested that rate of erosion decreases with increase of impact angle of target specimen. Hence the main objectives of the experiment were achieved. CHAPTER 8 Future work The project discusses conditions to avoid erosive wear for mild steel impacted by olivine sand. The vast nature of subject gives the opportunity to carry out the experiment by changing various properties of impact materials and target materials and testing conditions. Some of the experimental works which were not possible to carry out during the present work and would be possible in future are suggested. The next work can be carried out by applying electro static charge to the olivine sand using electrostatic ring sensor equipment. The aim of using electro static ring sensor equipment is to find out charge to mass ratio. Another work that can be suggestible is combination of powder with sand. This is because every powder has its own properties, but when they mix with other materials they lose original properties and adopt new properties. This can be helpful to find out the new test procedure to avoid erosive wear for materials that can be impacted by olivine sand and other material m ixture. The other important future work could be comparing of the present project result with the gas blaster erosion tester. From the result of this work, it can be observed that the accuracy of the tester would result in accurate results, so it is suggested that, to improve the accuracy of the centrifugal accelerator tester. REFERENCES   K. Shimoda, T. Yukawa, Erosion of pipe bend in pneumatic conveyor,in: Proceedings of the 6th International Conference on Erosion byLiquid and Solid Impact, Cambridge, UK, September 5–8, 1983. Kilburn Engineering. Material Handling System. Available: http:/kilburnengg.com. Last accessed 10th February 2011. Mr Ben. Erosive wear. Available: http://tribologynews.com/2009/08/erosive-wear. (2009). Last accessed 4th Feb 2011. Terence F.J.Quinn. Physical analysis for tribology. Polished by syndicate of university Cambridge.Year(1991). P1-3.   M J Neale and M Gee. Wear Problems and Testing for Industry.   William Andrew publishing. (200). p1-71.   Deng T., The influence of particle dynamics on erosion caused by solid particles within laboratory erosion testers ,PhD Thesis ,The University of Greenwich, London UK (2001).   Tirupataiah Y, Venkataraman, B. and Sundararajan, G. The nature of theelasticrebound of a hard ball impacting on ductile metallic target materials. Materials Scienceand Engineering a-Structural Materials Properties Microstructure and Processing. Year (1990).p167-172. Roy, M., Ray, K. K. and Sundararajan, G. An analysis of the transition from metalerosion to oxide erosion. Wear. Year (1998).p122-128. Ruff A W, Ives L K. Measurement of solid particle velocity in erosive wear,  Wear 35. (1975).P195-199. Kosel, T.H Anand, k., An optoelectronic erodent particle velocimeter, in V. Srinivasan and K. Vedula (eds.), corrosion and particle erosion at high temperature, The minerals, metals and materials society, 1989, PP 349-368 Dr.Dmitri Kopeliovich. Mechanisms of wear. Available: substech.com. 2009. Last accessed 4th Feb 2011. B.G Mellor. Surface coatings for protection against wear. Woodhead. (2006). p1-58. J G A BITTER.  A Study of Erosion Phenomena. Wear. (24-aug-1962). P5-21. Heinrich Reshetnyak, Jakob Kuybarsepp. Mechanical properties of hard metals and their erosive wear resistance. Material Engineering . (1994). P185-193. Bharat Bhushan. Introduction to tribology.   John willey sons. Year (2002).p331-336   Pallcorporation. Erosive wear.  Available: pall.com/Aerospace_18153.asp. (2010). Last accessed 08/02/2011. Fiinie I. The Mechanism of Erosion of Ductile Metals.  Proceeding of the US national congress of applied mechanics. (1958). p527-532 Burnetta, S. R. De Silvab and A. R. Reeda. Comparisons between â€Å"sand blast† and â€Å"centripetal effect accelerator† type erosion testers. Wear. (1995). P168-178. Deng T, Chaudhry A.R , Patel M,Hutchings I, Bradley M.S.A. Effect of particle concentration on erosion rate of mild steel bends in a pneumatic conveyor. Wear. (2004).  Ã‚   P480-487.   Deng T, Li J , Chaudhry A.R., Patel M, Hutchings I , Bradley M.S.A. Comparison between weight loss of bends in a pneumatic conveyor and erosion rate obtained in a centrifugal erosion tester for the same materials. Second International Conference on Erosive and Abrasive Wear. (2005). P402-411.  Fiinie. Some observations on the erosion of ductile metals. Wear. (2-jul-1971). P81-90. Deng T, Bingley M.S, Bradley M.S.A, De Silva S.R. A comparison of the gas-blast and centrifugal-accelerator erosion testers: The influence of particle dynamics. Wear. (2008). p945-955. Gwidon W. Stachowiak, Andrew W. Batchelor, Grazyna Stachowiak. Experimental methods in tribology . Elsevier B.V. Year (2004). p82-92. Shenzhen seto Industries Co., Ltd. Available : sznorinco.com/machines/feeder/circular_feeders.htm.(1979), Last accessed 08/04/2011.   M G Gee and I M Hutchings, General Approach and Procedures for Erosive Wear Testing, Measurement Good Practice Guide No. 56, University of Cambridge, Institute for Manufacturing Department of Engineering, 2002, pp18-20 Allen, T. â€Å"Particle Size Analysis†, Chapman Hall, London, 1975. John T. Germaine, Amy V.The information about sieve shaker. Germaine, 2009,PP67-78 Miranda Griggs.  Mild Steel Properties.  Available: buzzle.com/articles/mild-steel-properties.html. Last accessed 9th April 2011. http://mineral-metals.exportersindia.com/industrial-minerals/olivine-sand.htm for the study of olivine sand. Last accessed 2nd April 2011. Peter A ciullo, the study of Olivine sand, 1996, pp123-127.

Johnson Controls Research Paper Example | Topics and Well Written Essays - 1250 words

Johnson Controls - Research Paper Example Information systems are also considered long-term capital investment projects. The following are some of the traditional capital budgeting models used to evaluate capital projects: The payback method The accounting rate of return on investment (ROI) The net present value The cost-benefit ratio The profitability index The internal rate of return (IRR) These methods rely on measures of cash flows into and out of the firm. Capital projects generate cash flows into and out of the firm. The investment cost is an immediate cash outflow caused by the purchase of the capital equipment (capital outlay). In subsequent periods, the investment may cause additional cash outflows related to repair and maintenance that will be balanced by cash inflows resulting from the investment. Cash inflows take the form of increased revenues generated from the improved facilities or reduced costs in production and operations. The difference between cash outflows and cash inflows (net cash flows) is used for ca lculating the financial worth of an investment. Once the cash flows have been established, several alternative methods are available for comparing different projects and deciding about the investment. Financial models assume that all relevant alternatives have been examined, that all costs and benefits are known, and that these costs and benefits can be expressed in a monetary terms. When one has to choose among many complex alternatives, these assumptions are rarely met in the real world, although they may be approximated (Aggarwal, 2002). Tangible benefits can be quantified and assigned a monetary value. Intangible benefits, such as more efficient customer service or enhanced employee goodwill, cannot be immediately quantified but may lead to quantifiable gains in the long run. Shim and Siegel (2008) argue that traditional capital budgeting has a number of challenges. The models do not express the risks and uncertainty of their own costs and benefits estimates; cash flows are unce rtain; inflation may affect costs and benefits differently; technology—especially information technology—can change during the course of the project, causing estimates to vary greatly; intangible benefits are difficult to quantify. These factors wreak havoc with financial models. The difficulties of measuring intangible benefits give financial models an application bias. Traditional approaches to valuing information systems investments tend to assess the profitability of individual systems projects for specific business functions. Theses approaches do not adequately address investments in IT infrastructure, testing new business models, or other enterprise-wide capabilities that could benefit the organization as a whole (Gregory, 1999). The traditional focus on the financial and technical aspects of an information system tends to overlook the social and organizational dimensions of information systems that may affect the true costs and benefits of the investment. Howeve r, there are other modern methods that can be used as alternatives to the traditional methods. One of the approaches is the option pricing or real options theory recognizes the interactions among option holders’ optimizing behavior, asset uncertainty, and market disciplines. Recently, the option pricing theory has been applied in the evaluation of nonfinancial assets or ‘

Making career Personal Statement Example | Topics and Well Written Essays - 2000 words

Making career - Personal Statement Example These entry-level positions are actually glorified secretarial jobs wherein responsibilities include making sure that ads move smoothly through the execution process. Accordingly, depending on the agency an account executive or an account coordinator may be given some competitive-analysis responsibility (see the job post in this website: http://jobs.guardian.co.uk/job/320526/press-media-account-executive-various-accounts-to-24k) Indeed, according to a book published by Wetfeet, Inc. on careers in advertising and PR, "the lower you are on the account [management] totem pole, the more it's about execution. The higher you are, the more it's about strategy." (p. 99) In analysing a job advertisement in fig. 1, it is easy to understand that people entering account management must have strong social skills, since a good chunk of their job involves managing people. As one insider said, "As you move up in account management, one of your responsibilities becomes managing people below you. But even the lowest levels, you're managing people in other departments." They should be able to think like fashion entrepreneurs/designers and creatives since they have to deal with both camps. As Wetfeet, Inc., a leading PR firm emphasized, in terms of personality, creatives and clients are often diametrically opposed and the better direction you give the creatives, the better ads you get. With these facts on hand, I conclude that people with their sights set on advertising account management in the fashion industry should be organised and good at multitasking, because they'll be working on a variety of things simultaneously. In addition, account management candidates should have a good understanding of marketing and selling fashion merchandise, since the job is about helping clients sell their goods and selling the agency to others. TASK 2: It has been said that The Good Girl or The Good Boy syndrome hardly ever lands an employee to top leadership post and even slows down professional growth and career progress in the advertising industry. Here an employee place more value on being in good terms, and therefore agreeable, with his superiors at the expense of searching for new and better ideas that will benefit his company or the product that the company markets. In the advertising industry, where innovation is very important, the pathway to a better career trajectory is to adopt the contrarian position - the ad man who finds new path, ends up moving the company or a product ahead. I believe that bringing this unique perspective to work in the advertising field offers growth opportunities and expands possibilities for the company that I will work for as opposed to maintaining the status quo or being docile in the fast-paced and cutthroat competition in the advertising world. One of my resource persons confirmed this line of thinking as she told her own success story. Alexa Simons was an assistant account manager for a mid-size advertising agency. Their accounts, however, were impressive. Her team, for instance, services the PR and advertising needs of a perfume line. About a year ago, this client decided to decentralise their advertising in the management's belief that the advertising efforts are not delivering quantified returns. Alexa's superior accepted the decision and devised strategies that worked around what the client wanted. However, after a month Alexa took the initiative of reviewing consumer research and found that certain critical measures had declined sharply after the

Understanding of culture and cultural differences as fundamental for Essay

Understanding of culture and cultural differences as fundamental for international marketing - Essay Example The researcher states that culture and cultural differences has not only impacted on the effectiveness of firms with respect to international competitiveness, but has also progressively generated negative effects regarding efficient usage of international marketing resources. Success of international firms is basically dependent on their international marketing strategies that incorporate cross-cultural intelligence aspects. Moreover, international marketing professionals continuously seek to understand global cultures and cultural differences that exist in the international specific markets ventured. Understanding cultural variations that exists among customers and target markets is important for developing an international marketing strategy that is universal and covers all customer needs. Application and outcome of professional marketing largely depends on the extent to which cultural differences are evident among customers. Firm’s competitiveness in the international marke t recognizes cross-cultural factors as determining factors with which comprehensive information is gathered from the various markets to enable formulation of best marketing strategies. Generally, cross-cultural analysis in the international market is similar to domestic market analysis, although international analysis places much emphasis on cultural aspects due to cross border cultural variations. However, domestic markets have also continued to diversify their cultures although as much as the international markets. ... However, domestic markets have also continued to diversify their cultures although as much as the international markets. Political, cultural, and social barriers and variation in the international markets have remained significant challenges to multinational companies that fail to recognize variations, and thus need for different business strategies. Nevertheless, international marketing strategies are more complex and sophisticated with respect to cross border variations as compared to domestic marketing strategies (Rugimbana & Nwankwo, 2003, p.331). International marketing recognizes a variety of cultural aspects that define one country’s culture from the other. Culture is defined and differentiated by technologies with regards to timing, moving, storing, analyzing, and producing information, as well as motives, accuracy, types, timeliness of data collection, language barriers, ethical standards, and attitudes of individuals collecting information. Different clients from dif ferent cultures seek to satisfy similar needs in different ways, which constitute cultures and common practice. Marketing professionals need to devise marketing strategies and products that are not biased to a particular culture, and are able to cover all cultural needs in question. Through research and information analysis, marketing professionals are able to understand the different needs of their customers with regards to their cultural variations. Cross-cultural analysis is carried out by relevant marketing professionals on the target markets of the firms they work for. International marketers seek to analyze particular cultures and the differences pertaining to their marketing strategies using relevant models of study and analysis. Here, cross-cultural research models used by

Normative development way of using stages of development

Normative development way of using stages of development Normative development is viewed as a way of using stages of development, matching ages to ability or skills and using the milestones approach' (Dryden, L et al 2005 p68) Milestones demonstrate what most children are likely to be doing by a specific age for example being able to hold your head up, look and communicate between the ages of 0 to 8 months and started walking and talking by the ages of 24 and 36 months. However, these may be helpful documented series of steps but there are individual factors that may influence the childs individual development. Beaver. M, et al (2002) p100/101 These influences are now recognised as being critical in the growth and development of the brain and in the process of how children learn and develop. The adult is the most important factor in childrens learning and part of the of adults role is to gain important knowledge of the factors and life experiences surrounding the child that are influencing the childs holistic development. (Dryden, L et al 2005 p68) Along with observations, all background information and relevant knowledge surrounding the individual child can be taken into consideration. This assists the practitioner in understanding the stage of development the child is that and helps to provide essential and efficient learning and support for the child. Some of these may include genetic or medical factors where inherited genes impact on a childs physical development. For example, a child with additional support needs may not walk or talk at the documented milestones of 24 and 36 months, so the medical model of disability would, in the past, concentrate on what the child was unable to do. When working with any child, practitioners should provide a suitable curriculum that changes to the needs of the individual child. Adults providing the necessary learning that supports the individual child will be respecting, responsive and be able to concentrate on what the child is able to do and get it right for the individual. (Dryden, L et al (2005) p69) Kellmer Pringle (1980) highlighted four developmental needs that have to be met equally to ensure development and these include the need for love and security, the need for new experiences, the need for praise and recognition and the need for responsibility, cited in Essential Early Years, Dryden, L et al (2005). The availability and influence of love, affection and security can impact on the childs mental and social development and these needs can be met by the parents or main carer by providing a stable, continuous, dependable and loving relationship. In practice, practitioners will have the responsibility to be aware of promoting positive relationships and by ensuring they put this into action they can influence positive outcomes for children. Pre-birth to Three: Positive Outcomes for Scotlands Children and Families, (2010) Other influences on a childs development can include environmental factors of overcrowding in housing, air pollution or poverty. Poverty can have a severe effect on a childs holistic development, for example a child may live in an area that is dangerous to play so the childs play is restricted. Lindon, J (2010) p205 This restriction could influence on the childs social and emotional development. Children living in an environment of poor or no income may see their basic needs not being met and because of this may underachieve at school. Practitioners should work alongside parents and gain background knowledge of the childs home situation to enable them to provide the appropriate care, support and learning the individual child needs. Appendix 1 It is with this in mind that the Scottish Government has decided that practitioners are required to use the Pre-birth to Three documented guidance to help children and young people improve their outcomes. Adam Ingram, Minister for Children and Early Years explains: Through prevention and early intervention, we can provide children with the social and emotional support needed to help fulfil their potential and break the cycles of underachievement which often blight some of our most disadvantaged communities. Pre-birth to Three: Positive Outcomes for Scotlands Children and Families, (2010) My knowledge of the childs holistic development now includes an understanding of how the developing brain influences a childs learning and development. I gained knowledge of how the critical period from pregnancy to around three years can have an influence on the outcomes the child is likely to have in later life. During pre-birth a babys brain cells are developing, connecting and communicating and this is enabling the baby to learn and develop some of their senses and in particular, taste and hearing. It is during this period that the mothers emotional experiences can influence and affect the babys developing brain. (Pre-birth to Three: Positive Outcomes for Scotlands Children and Families, (2010)). Brain development relies on the formation and connection of cells and these connections can grow quickly with the help of the babys early experiences and relationships. However, the mothers use of either drugs or alcohol can be badly damaging for the developing brain. (Dryden, L et al 2005 p68) The developing brain makes many more connections than required and if the baby has had proper care and support in the first year of life, some of the connections can start to be removed. In order for further brain development to progress appropriately there must be sufficient involvement and action through interactions with others for the child. These interactions allow the child to revisit and reinforce the brain connections and keep alive the signals already made. I believe it is crucial for practitioners to have knowledge of the developing brain because they will understand the learning process that children use in their normal development and how this can impact on their future outcomes. It is during our very best earliest years and even pre-birth that a large part of the pattern for our future adult life is set. (Scottish Government, 2008d, p1) The Scottish Government has introduced a document of national guidance for early years establishments to guide practitioners in providing the best start every child deserves. Pre-birth To Three: Positive Outcomes for Scotlands Children and Families lays out the requirements, support and information practitioners need to provide children and their families the best opportunities available. The four key principles are: Rights of the Child, Relationships, Responsive Care and Respect and within these principles are nine equal features of practice that can be used to support staff in their implementation of the key principles. These features include: Role of staff, Attachments, Transitions, Observations, Assessment and planning, Partnership Working, Health and Wellbeing, Literacy and Numeracy, Environments and Play. (Birth to Three document 2010 p11) I used this guidance for my own professional development and self-evaluation of observations of a child under three and I have related my findings of Shannons development to some relevant theorists and their theories around normative development. Observation one seen Shannon interact in role play with another child and an adult. The play is initiated by Shannon by telling Uncle Dale I am a dolly. Uncle Dale knows that this statement from Shannon means she wants to play her game. Bruce, T (2006) suggests that children aged from 2 to 3 years will become absorbed in symbolic play where they pretend to be someone else and in this case the talking doll. Moreover, from the ages of 3 to 4, children will develop Theory of Mind by trying out what it is like to be someone else. Bruce, T (2006) p328 Appendix 2 In observation two, I believe I was able to maintain the positive relationship I have with Shannon and this is shown through her confident interactions with me with the pretend spider. My sensitive actions and interactions of smiles, hugs and giggles enabled her to feel safe, secure and loved within an environment that was not her home. Through these interactions, she can build on her ability to create other relationships, build up trust and satisfy her individual social and emotional needs and development. I n addition, Shannon was able develop her physical development by carrying out simple age related physical movements involving her fine motor skills and hand to eye coordination when holding the spoon to ice the cakes. Beaver. M, et al (2002) p76 This planned experience enabled me to respect Shannon as a unique individual. Through my responsive care I was able to reassure Shannon that, as a significant adult in her life, I was reliable and trustworthy and would respond to her needs. This will enable her to feel secure within herself and able to trust other adults. As she had built up trust and a positive relationship with me, she was able to express herself through her imaginary play and develop her social and emotional development. Observation two also gave me the opportunity to assess Shannons language and communication development. Lindon, J (2010) explains how children can use gestures and sounds to attract and hold the attention of adults. Lindon, J (2010) p122. I believe Shannons gesture of clapping her hands when finished the task showed she wanted to get my attention and also relayed to me her sense of excitement and accomplishment. This form of communication by Shannon was rewarded from me through responsive care of praise and recognition, a feature of the Skinners behaviourism theory of language. (Skinner. B.F), as cited by Lindon, J (2010) P115 Appendix 3 In observation 3 I observed Shannon using patterns of repeated behaviour (schema) in her play by repeatedly connecting and disconnecting the toys she was playing with. Piaget believed that children organise their thinking to past experiences and events and linked them to what will happen next. Lindon, J (2010) p 29 In the context of Shannons observation, I believe the connecting and disconnecting of the doll and parts were her way of trying to organise her thoughts and making sense of her world, i.e. she was getting a new friend (connection) and Mason was not going back to Donnas (disconnection). Shannons level of development can be related to Piagets theory of stages of cognitive development and in particular the Pre-operational stage where language abilities develop quickly.

Gay Marriages Essay -- Argumentative Persuasive Essays

Gay Marriages Growing up in a heterosexual neighborhood, gay couples were not something that you came across every day as you do in today’s time. At the age of 22, Dawn was introduced to her first gay couple, Mike and Thomas. They were friends of her husband. She had never known a gay couple before or even a gay person. It was extremely strange and uncomfortable for Dawn to be in the presence of two gay men. It was nothing out of the ordinary at first. To Dawn, it was just like two men living together as roommates until they kissed. Dawn felt like she was invading on their privacy as she sat and watched them kiss. She quickly turned her head so she would not be intruding. Now, Dawn is extremely close to Mike and Thomas. She claims them to be some of her best friends. They have shared many life experiences together; their children have grown up together. Over the years that have past, Dawn has come to realize how unfair it was for her to be married to the love of her life. When two people who love each other just as much could not have, their love recognized in the court as hers is. Years have passed since that first day she was introduced to her first gay couple. Seven years to be exact, Mike, Thomas, Dawn and her husband are still very close friends to this day. She is extremely glad that day happen in her life because her life has been enriched with two of the most awesome men. Dawn will know or ever know. Dawn hopes one day that every state will recognize same-sex marriages as not something to frowned upon but something that will make our country thrive. Dawn hopes in writing this paper it makes some people change their minds on same-sex marriages. Gay and lesbians face as many challenges as minorities if not more... ...criminate just because someone is different from us or believes something different from us? If so, we would have a lot more discrimination going on than what we do now. Because no one is going to agree with everything, we do or believe in. Who has the right to say that two people should not be given the right to marry? Why should two homosexual people not be given the same rights to marry as a heterosexual couple? Works Cited D, Emilio, John, Turner B. William and Urvashi Vaid. Creating Change: Sexuality, Public Policy and Civil Rights. New York: St. Martin’s Press, 2000. Kranz, Rachel and Tim Cusick. Gay Rights. New York: Facts On File, Inc. 2000. Merriam-Webster. Merriam-Webster Online Dictionary 2004. 28 Jan. 2004 Oliver, Marilyn Tower. Gay and Lesbian Rights: A Struggle New Jersey: Enslow Publishers, Inc, 1998.

Education in Evolution: from Freire’s Bank Clerk to Problem Poser

Our portrait as students is an evolution of experiences of continuous life’s challenges and disasters. In our childhood, we consider our parents the first teachers. In the process of growing and maturing, we join the educational world going to school at the same time that we are introduced to the school of life. As scholars, we have experienced Freire’s two educational methods – bank-clerk and problem-posing.It is true that the educator would decide what method to employ, however, at the end, most of us, including the students depicted in ancient and modern literature, would choose to be critical thinkers and exhibit Freire’s â€Å"Emerging Consciousness†, opening the door to creativity, critical and a revolutionary learning process. Usually, the beginning of our education starts at home; our parents are the first ones who teach us how to behave with manners and cultural customs. The education that we received at home can be different for everybody and the reason is different cultures, languages, and religion.The way our parents and families teach us can be defined as coalition of bank clerk and problem posing methods, the parents are the teachers and we are the students, sometimes the parents use the â€Å"banking† concept, they talk and give commands and the students just listen and accept the commands. As Freire declares Education thus becomes an act of depositing, in which the students are the depositories and the teacher is the depositor. Instead of communicating, the teacher issues communiques and makes deposits which students patiently receive, memorize, and repeat.This is the â€Å"banking† concept of education, in which the scope of action allowed to the students extends only as far as receiving, filing, and storing the deposits (Freire 72). Freire tells us that using â€Å"banking† education, the parents become narrators and the children just containers to be filled with the parents’ knowl edge. Pedagogy of the Oppressed emphasizes that communication between parents and children, doesn’t exist in a â€Å"banking† education. â€Å"Banking† education means suppression and by suppression, children are limited to extend their learning process by being filled by the parents’ ideas.But do the parents realize that using a bank-clerk method minimizes or annuls their children’s creative power? Some parents do not realize it, they become oppressors and their children the oppressed. They consider their children inexperienced and ignorant. The parents think that their children have to learn what they teach them without asking or questioning anything, this way they would be integrated into the society accepting the passive role imposed on them. Strepsiades can be a good example of a father using â€Å"banking† education. Strepsiades wants his son to join the Thinkery to learn the two logics to save him from his debts.In the beginning, Phei dippides does not want to join the Thinkery because he believes that people from the Thinkery are crazy and what is taught is a fraud. Finally, Strepsiades persuades Pheidippides and he joins the Thinkery. Strepsiades claims â€Å"So tutor him in your two logics – traditional Philosophical Logic and that flashy modern sophistic logic they call Immoral because it’s so wonderfully wicked. In any case, if he can’t master both logics, I insist that he learn the Immoral Kind of argument† (The Clouds 66). Strepsiades does not question Socrates methods, he tells Socrates to take his son as his student and teach him the two logics.Stresiades does not care whatever it would take for Pheidippides to learn the two logics. Stresiades sees Pheidippides just as tool that would server the purpose of avoiding to pay his debts. Pheidippides is the oppressed and he can not question or criticize any method that they would use in the Thinkery to teach him the two logics. How ever, other parents like mine, using a coalition of both educational methods, sometimes talk in a mandatory way and nothing is negotiable; as Colonel Graff, the head of the battle school, does with Ender.Occasionally, my parents talk to me as a friend in a rational way, sharing their experiences and exposing their problems. As equal human beings, we reach the communication between teacher and student; in the process of learning from each other we expose Freire’s â€Å"emerging consciousness†. We do not see parents just as an authority, we see them as friends, together, through dialogue, critical criteria, and creativity we develop a problem-posing education.In Ender’s case, he is the third child of the Wiggin’s family; he knows that he could not stay with his biological parents, his instincts push him toward new experiences and the discovery of new things. He leaves his parents in an early age to join a battle school. Beginning on that day, Colonel Graff acts as Ender’s father at the school and Ender’s life would not be the same again. Like Ender, I felt the same attraction when I first joined culinary school at age of 13, leaving my family far away to experience one of the biggest challenges in my life.I would be alone in a place where everything and everybody was unknown to me. This life experience was a vital part of my educational journey. As Freire believes â€Å"Students, as they are increasingly posed with problems relating to themselves in the world and with the world, will feel increasingly challenged and obligated to respond to that challenge† (Freire 81). Freire thinks that when we find challenges in our life, that relate to ourselves, we develop the power to perceive critically the way of our existence in the world and in which we find ourselves; becoming teachers-students and students-teachers.Graff enforces â€Å"banking† education on Ender, manipulating, isolating, and limiting his existenc e in the school. Graff believes We could be wiped out and it would adjust, it would get on with the next step in evolution. But humanity doesn’t want to die. As a species, we have evolved to survive. And the way we do it is by straining a straining and, at last, every few generations, giving birth to genius. The one who invents the wheel. And light. And flight. The one who builds a city, a nation, an empire. (Ender’s Game 35). Graff explains to Ender why they chose him to join the battle school.He tells Ender that they expect him to be a hero and save humanity. As a tutor and teacher. Graff, being a bank-clerk, pushes Ender to his limits, but Ender’s reaction is different, the more they challenge and isolate him the more he awakes his emerging consciousness. Ender soon becomes the best strategist and leader of the battle school. On the other hand, Pecola’s story is totally different from Ender’s. Pecola bears the blame for the sins, crimes, mistake s or misfortunes of her parents, she suffers abuses from her parents, and people at the school even the cashier from the grocery store that sees through her.She is treated as a marginal person who does not fit in to white people’s view of what beauty means for society. For Pecola, beauty means to have blue eyes. Pecola feels As long as she looked the way she did, as long as she was ugly, she would have to stay with these people. Somehow she belonged to them. Long hours she sat looking in the mirror, trying to discover the secret of the ugliness, the ugliness that made her ignored or despised at school, by teachers and classmates alike. She was the only member of her class who sat alone at a double desk. The blues eye 45). Pecola does not like the world of isolation and oblivion where she lives. She associates black with ugliness. She tries to find an answer to why people ignore and despised her at the school and at home. She thinks that the solution for all her problems is to get blue eyes, and for her blue eyes are synonymous of acceptance and beauty. Unfortunately Pecola’s experiences at the school are not pleasant, fortunately, we join the educational world going to the school, and enjoying the adbantanges of education.The school of life together with the other educations helps us to improve our civilization. In this process, we find educators that would choose the â€Å"banking† system or the problem posing method. In my experience, some of the professors that I had in the past, used â€Å"banking† system; they would become transmitters and we would be the receptors. Most of the time with this kind of education you learn whatever the teacher tells you to learn, but in a short period of time this information would disappear. With a problem-posing education there is a relationship between professor and student.The class would become more active and teacher and student would become subjects of the educational process and humanism, they would learn from each other. Freire believes Those who use the â€Å"banking† approach, knowingly or unknowingly (for there are innumerable well-intentioned bank-clerk teachers who do not realize that they are serving only to dehumanize), fail to perceive that the deposits themselves contain contradictions about reality. But, sooner or later, these contradictions may lead formerly passive students to turn against their domestication and the attempt to domesticate reality.They may discover through existential experience that their present way of life is irreconcilable with their vocation to become fully human (Freire 75). Freire tells us that sometimes bank-clerk teachers do not realize that this method affects the students. It limits their thinking capability to be critical, to be creative and to develop new theories or ideas. He also tells us that the contradictions about reality sometimes may lead the passive students to awake their consciousness and to go against thei r teachers and the â€Å"banking† method in order to become fully human.For example, Ender usually is pushed to his limits by Graff who uses a â€Å"banking† method, isolating him from the rest of the students, challenging and changing the rules always. But Ender never surrenders, he answers his teachers in a problem poser way solving all the challenges using his emerging consciousness. It is true that at a certain point, Ender believes â€Å"It’s the teachers, they’re the enemy. They get us to fight each other, to hate each other. The game is everything. Win win win. It amounts to nothing† (Ender’s game 108).Eventually, Ender sees the teachers as his enemies and the game as nothing, which he demonstrates through such actions as his at the battle against two armies. As Freire says the contradictions about reality, leads the passive students to turn against the domesticate reality. Ender declares â€Å"I’m trapped here, Ender thought, trapped at the End of the World with no way out. And he knew at last the sour taste that had come to him, despite all his successes in the Battle School. It was despair† (Ender’s Game 141).Ender tells us how he feels about being manipulated and also about lacking control over his own life. He fears the possibility of running out of ideas and not being able to win. He is worried because he has a huge responsibility. He is the last hope of the humanity. He knows that if he wants to win against the Buggers he has to learn more about them, he has to learn how to love his enemies, this way he finds their weaknesses and he uses this strategy to destroy them. However, Ender and Pheidippides are from different genres and belong to distant eras.Pheidippides in the Thinkery is exposed to radical thinkers like Sophistry and by highly imaginative thinkers like Socrates. Above all, this creates repercussion, undermining traditional values and corrupting the moral of youths. Sohpist ry is a clear example of a problem poser method and he teaches Pheidippides that the principles of a society, such as justice and truth, are just concepts that can be adapted or interpreted to the needs of society. After he graduates from the Socrates’ Thinkery, Pheidippides believes that he is a new man.Using his emerging consciousness he thinks that with this power he can challenge everybody and everything. Pheidippides points out â€Å"But now, now that Socrates has made a fresh Pheidippides of me, now that my daily diet is Philosophy, Profundity, Subtlety, and Science, I propose to prove beyond the shadow of a doubt the philosophical propriety of beating my Father† (The clouds 103). Pheidippides emerging consciousness allows him to break and create his own rules, he says that his father deserves the beating because his father ordered him to play a lyre and sing a song even when Pheidippides did not wish to do it.His father keeps ordering things and Pheidippides did not agree with his father’s wishes, consequently he beat his father. Pheidippides justifies his acts telling his father that he beats him because he loves him and he says that for him loving and beating are synonymous. Pheidippides emerging consciousness makes him a bully. Never mind Pheidippides, Pecola’s classmates torment and abuse her for being black and ugly, she is also raped by her father, and eventually she becomes pregnant by him.Although the baby dies, her mother treats her coldly, as she thinks Pecola is ugly and is ashamed of her. Pecola becomes a martyr, she just wants to disappear from this world. She thinks that she is responsible for all bad things that happen in the world. Claudia who is Pocola’s friend comments The damage done was total. She spent her days, her tendril, sap-green days, walking up and down, up and down, her head jerking to the beat of a drummer so distant only she could hear. Elbows bent, hands on shoulders, she flailed her arm s like a bird in an eternal, grotesquely futile effort to fly.Beating the air, a winged but grounded bird, intent on the blue void it could not reach—could not even see—but which filled the valleys of the mind. (The bluest eye 204). Claudia describes Pecola who has lost her mind. Pecola is force farther into her fantasy world, which is her defense against violence and cruelty. The school of life awakes Pecola’s emerging consciousness in a different way from the other students, instead to expose to the world and confront the challenges; she drives herself into a state of madness over the blue eyes.Tired of a dark and sad world she decides to disconnect with the reality and she creates her world, with her own rules and friends where everything is beautiful and perfect, where she has the bluest eyes. It is true, that our emerging consciousness is the result of our different educations that is based on a problem-poser method, it does not serve the concern of the opp ressor. Freire thinks as revolutionaries, we perceive the world as a reality in the process of evolution instead of a static reality. Therefore we should strive for a humanist society.