Friday, May 22, 2020

Power Factor - Free Essay Example

Sample details Pages: 11 Words: 3402 Downloads: 4 Date added: 2017/09/20 Category Energy Industry Essay Type Argumentative essay Tags: Energy Essay Did you like this example? Power factor: The power factor of an AC electric power system is defined as the ratio of the real power flowing to the load to the apparent power, and is a dimensionless number between 0 and 1 (frequently expressed as a percentage, e. g. 0. 5 pf = 50% pf). Real power is the capacity of the circuit for performing work in a particular time. Apparent power is the product of the current and voltage of the circuit. Due to energy stored in the load and returned to the source, or due to a non-linear load that distorts the wave shape of the current drawn from the source, the apparent power will be greater than the real power. In an electric power system, a load with low power factor draws more current than a load with a high power factor for the same amount of useful power transferred. The higher currents increase the energy lost in the distribution system, and require larger wires and other equipment. Because of the costs of larger equipment and wasted energy, electrical utilitie s will usually charge a higher cost to industrial or commercial costumers where there is a low power factor Linear loads with low power factor (such as induction motors) can be corrected with a passive network of capacitors or inductors. Non-linear loads, such as rectifiers, distort the current drawn from the system. In such cases, active or passive power factor correction may be used to counteract the distortion and raise the power factor. The devices for correction of the power factor may be at a central substation, spread out over a distribution system, or built into power-consuming equipment. Contents †¢ 1 Power factor in linear circuits o 1. 1 Definition and calculation o 1. 2 Power factor correction of linear loads †¢ 2 Non-linear loads o 2. 1 Non-sinusoidal components o 2. 2 Switched-mode power supplies o 2. Power factor correction in non-linear loads ? 2. 3. 1 Passive PFC ? 2. 3. 2 Active PFC †¢ 3 Importance of power factor in distribution systems †¢ 4 Measuring power factor †¢ 5 Mnemonics †¢ 6 References †¢ 7 External links Power factor in linear circuits In a purely resistive AC circuit, voltage and current waveforms are in step (or in phase), changing polarity at the same instant in each cycle. All the power entering the loads is consumed. Where reactive loads are present, such as with capacitors or inductors, energy storage in the loads result in a time difference between the current and voltage waveforms. During each cycle of the AC voltage, extra energy, in addition to any energy consumed in the load, is temporarily stored in the load in electric or magnetic fields, and then returned to the power grid a fraction of a second later in the cycle. The ebb and flow of this nonproductive power increases the current in the line. Thus, a circuit with a low power factor will use higher currents to transfer a given quantity of real power than a circuit with a high power factor. A linear load does not change the shap e of the waveform of the current, but may change the relative timing (phase) between voltage and current. Circuits containing purely resistive heating elements (filament lamps, strip heaters, cooking stoves, etc. ) have a power factor of 1. 0. Circuits containing inductive or capacitive elements (electric motors, solenoid valves, lamp ballasts, and others) often have a power factor below 1. 0. Definition and calculation AC power flow has the three components: real power (Active power) (P), measured in watts (W); apparent power (S), measured in volt-amperes (VA); and reactive power (Q), measured in reactive volt-amperes (var). The power factor is defined as: [pic] In the case of a perfectly sinusoidal waveform, P, Q and S can be expressed as vectors that form a vector triangle such that: [pic] If ? is the phase angle between the current and voltage, then the power factor is equal to the cosine of the angle, [pic], and: [pic] Since the units are consistent, the power factor is b y definition a dimensionless number between 0 and 1. When power factor is equal to 0, the energy flow is entirely reactive, and stored energy in the load returns to the source on each cycle. When the power factor is 1, all the energy supplied by the source is consumed by the load. Power factors are usually stated as leading or lagging to show the sign of the phase angle. If a purely resistive load is connected to a power supply, current and voltage will change polarity in step, the power factor will be unity (1), and the electrical energy flows in a single direction across the network in each cycle. Inductive loads such as transformers and motors (any type of wound coil) consume reactive power with current waveform lagging the voltage. Capacitive loads such as capacitor banks or buried cable generate reactive power with current phase leading the voltage. Both types of loads will absorb energy during part of the AC cycle, which is stored in the devices magnetic or electric fiel d, only to return this energy back to the source during the rest of the cycle. For example, to get 1  kW of real power, if the power factor is unity, 1 kVA of apparent power needs to be transferred (1  kW  ? 1 = 1  kVA). At low values of power factor, more apparent power needs to be transferred to get the same real power. To get 1  kW of real power at 0. power factor, 5 kVA of apparent power needs to be transferred (1  kW  ? 0. 2 = 5  kVA). This apparent power must be produced and transmitted to the load in the conventional fashion, and is subject to the usual distributed losses in the production and transmission processes. Electrical loads consuming alternating current power consume both real power and reactive power. The vector sum of real and reactive power is the apparent power. The presence of reactive power causes the real power to be less than the apparent power, and so, the electric load has a power factor of less than 1. Power factor correction of linear loads It is often desirable to adjust the power factor of a system to near 1. 0. This power factor correction (PFC) is achieved by switching in or out banks of inductors or capacitors. For example the inductive effect of motor loads may be offset by locally connected capacitors. When reactive elements supply or absorb reactive power near the load, the apparent power is reduced. Power factor correction may be applied by an electrical power transmission utility to improve the stability and efficiency of the transmission network. Correction equipment may be installed by individual electrical customers to reduce the costs charged to them by their electricity supplier. A high power factor is generally desirable in a transmission system to reduce transmission losses and improve voltage regulation at the load. Power factor correction brings the power factor of an AC power circuit closer to 1 by supplying reactive power of opposite sign, adding capacitors or inductors which act to cancel the inductive or capacitive effects of the load, respectively. For example, the inductive effect of motor loads may be offset by locally connected capacitors. If a load had a capacitive value, inductors (also known as reactors in this context) are connected to correct the power factor. In the electricity industry, inductors are said to consume reactive power and capacitors are said to supply it, even though the reactive power is actually just moving back and forth on each AC cycle. The reactive elements can create voltage fluctuations and harmonic noise when switched on or off. They will supply or sink reactive power regardless of whether there is a corresponding load operating nearby, increasing the systems no-load losses. In a worst case, reactive elements can interact with the system and with each other to create resonant conditions, resulting in system instability and severe overvoltage fluctuations. As such, reactive elements cannot simply be applied at will, and power f actor correction is normally subject to engineering analysis. 1. Reactive Power Control Relay; 2. Network connection points; 3. Slow-blow Fuses; 4. Inrush Limiting Contactors; 5. Capacitors (single-phase or three-phase units, delta-connection); 6. Transformer Suitable voltage transformation to suit control power (contactors, ventilation, ) An automatic power factor correction unit is used to improve power factor. A power factor correction unit usually consists of a number of capacitors that are switched by means of contactors. These contactors are controlled by a regulator that measures power factor in an electrical network. To be able to measure power factor, the regulator uses a current transformer to measure the current in one phase. Depending on the load and power factor of the network, the power factor controller will switch the necessary blocks of capacitors in steps to make sure the power factor stays above a selected value (usually demanded by the energy supplier), say 0. 9. Instead of using a set of switched capacitors, an unloaded synchronous motor can supply reactive power. The reactive power drawn by the synchronous motor is a function of its field excitation. This is referred to as a synchronous condenser. It is started and connected to the electrical network. It operates at a leading power factor and puts vars onto the network as required to support a system’s voltage or to maintain the system power factor at a specified level. The condenser’s installation and operation are identical to large electric motors. Its principal advantage is the ease with which the amount of correction can be adjusted; it behaves like an electrically variable capacitor. Unlike capacitors, the amount of reactive power supplied is proportional to voltage, not the square of voltage; this improves voltage stability on large networks. Synchronous condensers are often used in connection with high voltage direct current transmission projects or in la rge industrial plants such as steel mills. Non-linear loads A non-linear load on a power system is typically a rectifier (such as used in a power supply), or some kind of arc discharge device such as a fluorescent lamp, electric welding machine, or arc furnace. Because current in these systems is interrupted by a switching action, the current contains frequency components that are multiples of the power system frequency. Distortion power factor is a measure of how much the harmonic distortion of a load current decreases the average power transferred to the load. Non-sinusoidal components Non-linear loads change the shape of the current waveform from a sine wave to some other form. Non-linear loads create harmonic currents in addition to the original (fundamental frequency) AC current. Filters consisting of linear capacitors and inductors can prevent harmonic currents from entering the supplying system. In linear circuits having only sinusoidal currents and voltages of one freq uency, the power factor arises only from the difference in phase between the current and voltage. This is displacement power factor. The concept can be generalized to a total, distortion, or true power factor where the apparent power includes all harmonic components. This is of importance in practical power systems which contain non-linear loads such as rectifiers, some forms of electric lighting, electric arc furnaces, welding equipment, switched-mode power supplies and other devices. A typical multimeter will give incorrect results when attempting to measure the AC current drawn by a non-sinusoidal load; the instruments sense the average value of a rectified waveform. The average response is then calibrated to the effective, RMS value. An RMS sensing multimeter must be used to measure the actual RMS currents and voltages (and therefore apparent power). To measure the real power or reactive power, a wattmeter designed to work properly with non-sinusoidal currents must be used. S witched-mode power supplies A particularly important class of non-linear loads is the millions of personal computers that typically incorporate switched-mode power supplies (SMPS) with rated output power ranging from a few watts to more than 1  kW. Historically, these very-low-cost power supplies incorporated a simple full-wave rectifier that conducted only when the mains instantaneous voltage exceeded the voltage on the input capacitors. This leads to very high ratios of peak-to-average input current, which also lead to a low distortion power factor and potentially serious phase and neutral loading concerns. A typical switched-mode power supply first makes a DC bus, using a bridge rectifier or similar circuit. The output voltage is then derived from this DC bus. The problem with this is that the rectifier is a non-linear device, so the input current is highly non-linear. That means that the input current has energy at harmonics of the frequency of the voltage. This presents a particular problem for the power companies, because they cannot compensate for the harmonic current by adding simple capacitors or inductors, as they could for the reactive power drawn by a linear load. Many jurisdictions are beginning to legally require power factor correction for all power supplies above a certain power level. Regulatory agencies such as the EU have set harmonic limits as a method of improving power factor. Declining component cost has hastened implementation of two different methods. To comply with current EU standard EN61000-3-2, all switched-mode power supplies with output power more than 75 W must include passive PFC, at least. 80 PLUS power supply certification requires a power factor of 0. 9 or more. Power factor correction in non-linear loads Passive PFC The simplest way to control the harmonic current is to use a filter: it is possible to design a filter that passes current only at line frequency (e. g. 50 or 60 Hz). This filter reduces the harmon ic current, which means that the non-linear device now looks like a linear load. At this point the power factor can be brought to near unity, using capacitors or inductors as required. This filter requires large-value high-current inductors, however, which are bulky and expensive. A passive PFC requires an inductor larger than the inductor in an active PFC, but costs less. This is a simple way of correcting the nonlinearity of a load by using capacitor banks. It is not as effective as active PFC. Passive PFCs are typically more power efficient than active PFCs. Efficiency is not to be confused with the PFC, though many computer hardware reviews conflate them. A passive PFC on a switching computer PSU has a typical power efficiency of around 96%, while an active PFC has a typical efficiency of about 94%. Active PFC An active power factor corrector (active PFC) is a power electronic system that controls the amount of power drawn by a load in order to obtain a power factor as close as possible to unity. In most applications, the active PFC controls the input current of the load so that the current waveform is proportional to the mains voltage waveform (a sine wave). The purpose of making the power factor as close to unity (1) as possible is to make the load circuitry that is power factor corrected appear purely resistive (apparent power equal to real power). In this case, the voltage and current are in phase and the reactive power consumption is zero. This enables the most efficient delivery of electrical power from the power company to the consumer Some types of active PFC are: †¢ Boost †¢ Buck †¢ Buck-boost Active power factor correctors can be single-stage or multi-stage. In the case of a switched-mode power supply, a boost converter is inserted between the bridge rectifier and the main input capacitors. The boost converter attempts to maintain a constant DC bus voltage on its output while drawing a current that is always in phase with and at the same frequency as the line voltage. Another switchmode converter inside the power supply produces the desired output voltage from the DC bus. This approach requires additional semiconductor switches and control electronics, but permits cheaper and smaller passive components. It is frequently used in practice. For example, SMPS with passive PFC can achieve power factor of about 0. 7–0. 75, SMPS with active PFC, up to 0. 99 power factor, while a SMPS without any power factor correction has a power factor of only about 0. 55–0. 65. Due to their very wide input voltage range, many power supplies with active PFC can automatically adjust to operate on AC power from about 100 V (Japan) to 230 V (Europe). That feature is particularly welcome in power supplies for laptops. Importance of power factor in distribution systems The significance of power factor lies in the fact that utility companies supply customers with volt-amperes, but bill them for watts. Power factors below 1. 0 require a utility to generate more than the minimum volt-amperes necessary to supply the real power (watts). This increases generation and transmission costs. For example, if the load power factor were as low as 0. 7, the apparent power would be 1. 4 times the real power used by the load. Line current in the circuit would also be 1. 4 times the current required at 1. 0 power factor, so the losses in the circuit would be doubled (since they are proportional to the square of the current). Alternatively all components of the system such as generators, conductors, transformers, and switchgear would be increased in size (and cost) to carry the extra current. Utilities typically charge additional costs to customers who have a power factor below some limit, which is typically 0. 9 to 0. 95. Engineers are often interested in the power factor of a load as one of the factors that affect the efficiency of power transmission. With the rising cost of energy and concerns ove r the efficient delivery of power, active PFC has become more common in consumer electronics. Current Energy Star guidelines for computers (ENERGY STAR ® Program Requirements for Computers Version 5. 0) call for a power factor of ? 0. 9 at 100% of rated output in the PCs power supply. According to a white paper authored by Intel and the U. S. Environmental Protection Agency? , PCs with internal power supplies will require the use of active power factor correction to meet the ENERGY STAR ® 5. 0 Program Requirements for Computers. [17] In Europe, IEC 555-2 requires power factor correction be incorporated into consumer products. Measuring power factor Power factor in a single-phase circuit (or balanced three-phase circuit) can be measured with the wattmeter-ammeter-voltmeter method, where the power in watts is divided by the product of measured voltage and current. The power factor of a balanced polyphase circuit is the same as that of any phase. The power factor of an unbala nced polyphase circuit is not uniquely defined. A direct reading power factor meter can be made with a moving coil meter of the electrodynamic type, carrying two perpendicular coils on the moving part of the instrument. The field of the instrument is energized by the circuit current flow. The two moving coils, A and B, are connected in parallel with the circuit load. One coil, A, will be connected through a resistor and the second coil, B, through an inductor, so that the current in coil B is delayed with respect to current in A. At unity power factor, the current in A is in phase with the circuit current, and coil A provides maximum torque, driving the instrument pointer toward the 1. 0 mark on the scale. At zero power factor, the current in coil B is in phase with circuit current, and coil B provides torque to drive the pointer towards 0. At intermediate values of power factor, the torques provided by the two coils add and the pointer takes up intermediate positions. Another electromechanical instrument is the polarized-vane type. In this instrument a stationary field coil produces a rotating magnetic field, just like a polyphase motor. The field coils are connected either directly to polyphase voltage sources or to a phase-shifting reactor if a single-phase application. A second stationary field coil, perpendicular to the voltage coils, carries a current proportional to current in one phase of the circuit. The moving system of the instrument consists of two vanes which are magnetized by the current coil. In operation the moving vanes take up a physical angle equivalent to the electrical angle between the voltage source and the current source. This type of instrument can be made to register for currents in both directions, giving a 4-quadrant display of power factor or phase angle. Digital instruments can be made that either directly measure the time lag between voltage and current waveforms and so calculate the power factor, or by measuring both tr ue and apparent power in the circuit and calculating the quotient. The first method is only accurate if voltage and current are sinusoidal; loads such as rectifiers distort the waveforms from the sinusoidal shape. Mnemonics English-language power engineering students are advised to remember: ELI the ICE man or ELI on ICE – the voltage E leads the current I in an inductor L, the current leads the voltage in a capacitor C. Or CIVIL – in a capacitor(C) the current (I) leads voltage (V), voltage (V) leads current (I) in an inductor (L). Don’t waste time! Our writers will create an original "Power Factor" essay for you Create order

Sunday, May 10, 2020

Buying Best Presentation Topics for Students

Buying Best Presentation Topics for Students Social networking comments should be guarded by free speech. For instance, if you can't boast of being a strong writer, you will come to learn how to write any sort of essay if you practice writing on a normal basis. With the experience our writers have, they can let you select the best examples to use in your presentation. Only writers that are interested in your topic place will place a bid that will help you. Top Best Presentation Topics for Students Secrets Becoming professional and informative does not mean that you can't be fun! It's quite normal to be asked a few questions, especially in the event that you deliver a prosperous demonstration. You should repeat the key ideas throughout your presentation so the critical points stick! Speak to Your Teacher Your professors may provide you with a few special presentation ideas if you seek their help simultaneously. The Ugly Secret of Best Presentation Topics for Students You have to do what you can to make a huge effect on your audience and make sure that they will retain all of the info you presented to them. The U.S. government should offer internet service for each citizen. For instance, let's say you're giving a presentation to a possible client on the significance of content marketing and how you consultation services can develop the ideal on-line content advertising program. You can select any of the suggested topics to produce an intriguing college presentation. America should not offer foreign aid to other nations. It should act now to protect the quality of drinking water. Mixed martial arts ought to be banned. Year-round education isn't a great idea for student learning. All students ought to be asked to perform one particular year of community services. Some students might also have children that enjoy sports! If you buy an opportunity to deliver a business presentation, you can pick a topic from the list given below. A 1 hour essay deadline may be a true problem, if you're not good enough at writing and expressing your ideas on a topic you aren't really interested in. If for educational purposes you select a provocative topic, make sure it opens a discussion and doesn't pass a verdict against a particular community. It is always advised to select decent presentation topics that will excite and draw the interest of your audience. If you've got thorough grasp of the topic, then you can readily present your points to your audience via your presentation. In case the topic is too simplistic, their growing feeling of awareness could possibly be stunted. You may also ask your audience to talk about their private experience with your topic. The audience should understand and make a mental picture of this issue or message immediately. Deciding upon the right topic is the toughest task about creating a presentation. It isn't hard to choose the topic. The topic needs to be simple to illustrate. Your topic ought to be relevant to the academic path of material you're studying. If you've got little if any skills on the very same, you might jeopardize your career targets. Many speaking coaches advise that you eliminate slides altogether. Frequently, academic presentations are thought to be oral examinations. If you're a student with a desire to turn your presentation as interesting as possible, then you have to work on the presentation ideas you've got. You've been requested to provide a presentation. Get Help From a Professional If you truly need to receive your sales presentations right, think about bringing in an expert presentation agency that will help you. If you compose the PowerPoint presentations by yourself, make sure to request professional support in refining your final copy. A variety of topic choices can pose to be a true challenge and might call for lots of time for the selection approach. There are a great deal of great choices there when you're searching for songs for in-class pursuits. A great idea is to learn some impressive techniques from public speaking in order to create a relation to the audience. As you communicate your ideas throughout the audience, you have to be aware the ideal time to generate a joke or utilize humor.

Wednesday, May 6, 2020

Technology and Modern Communication Technologies Free Essays

Modern communication technologies such as mobile phones, e-mails and internet chat programs like the MSN Messenger have brought significant changes to our lives in recent years. Yet, there remains some disagreement as to whether the overall effect of this innovation has been positive or negative. Although there are valid arguments to the contrary, it is my belief that the majority of people in the globe have benefited greatly from these powerful and effective means of modern communication. We will write a custom essay sample on Technology and Modern Communication Technologies or any similar topic only for you Order Now To begin with, mobile phones and other tools of modern communication facilitate not only contact with friends and relatives in faraway places but also global business. With the click of a button, the vast amount of information can be transmitted from America to China in just a few seconds. Furthermore, it is generally felt that the access to these tools of communication is available in every corner of the world. With a mobile phone or a laptop, a person can talk or send messages online at a bus stop, in a corner shop or anywhere they could imagine. Therefore, it seems that these new forms of communication do bring a great deal of convenience to humankind. Nevertheless, opponents of modern communications claim that only the more privileged are able to enjoy the benefits. They further point out that the wide spread use of these efficient and effective ways of communication costs a considerable amount of money. Anyone who aims to use these innovations have to not only pay for the appliances such as a mobile phone or a computer but also cover up costs for communication services. Consequently, people who live in poverty are less likely to be benefited from modern communication technologies. By way of conclusion, I believe that modern communication technologies will benefit more people in the future as the pace of life increases; however, the have-nots cannot be ignored simply because they couldn’t afford it. Modern technology has increased material wealth but not happiness To what extend do you agree / disagree with the statement? According to recent statistics, the number of people who are stressed by the influence of a modern lifestyle is increasing. While having to suffer quick developments in advanced technology, people are always busy at work. Undeniably, modern technology makes people’s standard of living higher, however, I am convinced that people will not be happy while they live in a modern society with modern technology all around them. First, technological advances, resulting in increased degrees of industrialisation, have changed a lot of things in society, therefore, people living in that society have to suffer influences of these big changes, e. . , instead of working for eight hours a day and spending time with their families or going out to enjoy chatting over coffee with friends, people must be in their office and do a lot of work, maybe ten working hours per day, even they have to take works to do at home and their meals are always fast food. Do you think is that a happy life? Moreover, modern technology makes people’s life boring, after working time people often sit by their computer to play games o r reading some information on internet. That means they do not refresh their mind and by accident they turn their own into slave of modern technology. In fact, a lot of teenage get stuck in their lives, they think that there is nothing to learn and to enjoy because they know everything thanks to technological advances, thus, they choose the death for their solution. For all above reasons, I thoroughly believe that modern technology can not decide the happiness, it has improved people’s standard of living but not happiness. How to cite Technology and Modern Communication Technologies, Essays

Technology and Modern Communication Technologies Free Essays

Modern communication technologies such as mobile phones, e-mails and internet chat programs like the MSN Messenger have brought significant changes to our lives in recent years. Yet, there remains some disagreement as to whether the overall effect of this innovation has been positive or negative. Although there are valid arguments to the contrary, it is my belief that the majority of people in the globe have benefited greatly from these powerful and effective means of modern communication. We will write a custom essay sample on Technology and Modern Communication Technologies or any similar topic only for you Order Now To begin with, mobile phones and other tools of modern communication facilitate not only contact with friends and relatives in faraway places but also global business. With the click of a button, the vast amount of information can be transmitted from America to China in just a few seconds. Furthermore, it is generally felt that the access to these tools of communication is available in every corner of the world. With a mobile phone or a laptop, a person can talk or send messages online at a bus stop, in a corner shop or anywhere they could imagine. Therefore, it seems that these new forms of communication do bring a great deal of convenience to humankind. Nevertheless, opponents of modern communications claim that only the more privileged are able to enjoy the benefits. They further point out that the wide spread use of these efficient and effective ways of communication costs a considerable amount of money. Anyone who aims to use these innovations have to not only pay for the appliances such as a mobile phone or a computer but also cover up costs for communication services. Consequently, people who live in poverty are less likely to be benefited from modern communication technologies. By way of conclusion, I believe that modern communication technologies will benefit more people in the future as the pace of life increases; however, the have-nots cannot be ignored simply because they couldn’t afford it. Modern technology has increased material wealth but not happiness To what extend do you agree / disagree with the statement? According to recent statistics, the number of people who are stressed by the influence of a modern lifestyle is increasing. While having to suffer quick developments in advanced technology, people are always busy at work. Undeniably, modern technology makes people’s standard of living higher, however, I am convinced that people will not be happy while they live in a modern society with modern technology all around them. First, technological advances, resulting in increased degrees of industrialisation, have changed a lot of things in society, therefore, people living in that society have to suffer influences of these big changes, e. . , instead of working for eight hours a day and spending time with their families or going out to enjoy chatting over coffee with friends, people must be in their office and do a lot of work, maybe ten working hours per day, even they have to take works to do at home and their meals are always fast food. Do you think is that a happy life? Moreover, modern technology makes people’s life boring, after working time people often sit by their computer to play games o r reading some information on internet. That means they do not refresh their mind and by accident they turn their own into slave of modern technology. In fact, a lot of teenage get stuck in their lives, they think that there is nothing to learn and to enjoy because they know everything thanks to technological advances, thus, they choose the death for their solution. For all above reasons, I thoroughly believe that modern technology can not decide the happiness, it has improved people’s standard of living but not happiness. How to cite Technology and Modern Communication Technologies, Essays

Wednesday, April 29, 2020

Witness Study Guide free essay sample

Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging Article by Rosemary O’Shea WITNESS Director Peter Weir INTRODUCTION Peter Weir is an Australian director whose films are internationally renowned. In Gallipoli (1981), The Year of Living Dangerously (1982), The Mosquito Coast (1986) and Dead Poets Society (1989), he has created films that deal with groups under pressure. In Witness (1985) he provides the film audience with a window onto the world of the Amish in America. An Anabaptist Christian denomination particular to North America, the Amish are a devout, peaceful people. They keep themselves separate from the rest of society, believing that worldliness in the form of such modern developments as cars, tractors, electricity and telephones will distract them from devotion to God and living a simple life. Predominantly farmers, the Amish preserve traditional ways, wear plain, old-fashioned clothing and have a strong, supportive community spirit. This unites them and creates an intense sense of belonging. We will write a custom essay sample on Witness Study Guide or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Identity and Belonging in Witness Witness presents two contrasting worlds to viewers – gentle Amish farm life and the seedy world of big city crime and crime fighters. Weir’s film explores what it means to belong to these groups. He shows the moral certainty and strong bonds that come from belonging to a group which is different from the mainstream, as if this separation helps people achieve clarity about who they really are. A personal sense of self may be at odds with others’ opinions of you. People make judgements based on other people’s appearance and the groups they belong to. These stereotypes can be inaccurate and simplistic. In Witness, this is exemplified by the tourists’ amusement at the Amish. It is depicted also through the characters of Schaeffer and McFee, for whom being senior police officials provides an effective mask for their real identities as corrupt officers. Insight English for Year 12  © Insight Publications 2007 1 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging Weir explores the role that choice plays in determining identity. It becomes clear in the film that to be a member of a group is a powerful determinant of your sense of self. Values, attitudes and behaviours that have been instilled since childhood are internalised and not easily altered. Powerful cultural barriers exist between people from different groups, which affect their ability to form close relationships. The title of the film is worth considering in terms of the Context Exploring Issues of Identity and Belonging. These two disparate groups are reluctantly connected when the boy, Samuel, witnesses a murder. The duty in Amish life is to bear witness to God’s teaching. This is a binding force in their culture. When the entire community witnesses Schaeffer’s crime and corruption it is enough to defeat him. This is a powerful victory for the pacifist, anti-violence stance of the Amish, and Weir gives a final endorsement to the strength and goodness of the group. IDEAS ARGUMENTS IN THE TEXT Witness explores a number of key ideas relevant to the Context Exploring Issues of Identity and Belonging. These are outlined below and will be developed further in the following section. Overview of key ideas and arguments The Amish have resolutely chosen to separate themselves from mainstream American society. This choice demands significant sacrifices, not only of modern conveniences, but sometimes of full self-expression. Nonconformity by Amish members is not tolerated as this would compromise their separate identity and what makes them unique as a social group. However, as Witness shows, there is great support and acceptance for those who belong. Most people define their identity by the social group (or groups) to which they belong. John Book, his sister Elaine and the police officers, Carter and Schaeffer, are all products of a modern, complex world which requires them to come into daily contact with violence and corruption. The simple moral clarity of Amish life is denied to them. In this wider society, choosing to belong to a group Insight English for Year 12  © Insight Publications 2007 2 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging such as the police force can mean the chance to do good by fighting crime. However, it can also involve acts of violence and corruption in the pursuit of power and money. The film depicts the clash of these two cultures, exploring how people behave when they are estranged from their accustomed milieu and exposed to the scrutiny of strangers who are inclined to judge them by their allegiances. Witness also shows that a growing understanding between people from different cultures can force a painful evaluation of one’s own values, beliefs and sense of self. Analysis of key ideas and arguments Self-fulfilment and belonging to a group ‘No man is an island’, metaphysical poet John Donne tells us in his Meditation VII. Humans are social beings who thrive through their connections with others. We start life in family groups and identify ourselves as members of national and ethnic groups. We choose to mix with like-minded people in friendship groups and often find much in common with our work colleagues. Our beliefs and interests see us joining political parties, churches and football clubs. There is great satisfaction in associating with people who share something in common with us. In this sense, the groups we belong to show us and the world who we are. We develop a stronger sense of self when surrounded by people who understand and support us. John Book desires to do the right thing. He never falters in his determination to solve the murder of the undercover policeman and is never tempted to become part of the corrupt officers’ group. Book’s passion for justice is a fundamental part of his identity and is expressed in the career he has chosen. Book’s strong moral ethic is shared by Eli, who has taken on the support of his widowed daughter-in-law Rachel and grandson Samuel. Eli believes in a literal interpretation of the teachings of the Bible and lives his life accordingly. His behaviour bears witness to the Amish philosophy and belonging to the group allows him to lead a life that seems the most desirable and righteous to him. Insight English for Year 12  © Insight Publications 2007 3 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging Although we can assume that belonging to the Amish community was Eli’s birthright rather than a conscious choice, Witness shows him as a man who embraces the group and all its teachings wholeheartedly. The Amish community and its beliefs shape his identity and give his life meaning. Belonging to a group can provide a sense of being one part of a larger whole and sharing this belief with other group members can be very satisfying. Like the police investigating the murder scene, the Amish are shown working together towards a common goal. The raising of the barn, for example, shows the men combining their skills with mutual respect and without competition to get the job done. Here, Weir uses swelling music to establish a euphoric mood as the building takes shape with the work of many hands. The group may offer support and encouragement. At the funeral of Rachel’s husband we witness the subdued grief of the community at the loss of one of their own people. The women gather around Rachel in the dim room while the men stand together talking. This mutual support is seen again at the end of the film when the men run to answer the alarm bell, to come to the aid of whoever needs them. The common purpose and shared values of the group allow the Amish to find fulfilment in their ordered lives. Even for those who manipulate their position in a group for their own ends, such as the corrupt police officers Schaeffer, McFee and Fergie, there remains the possibility of self-fulfilment. The police force, and the respect that belonging to it confers, serve as a cover for these men to carry out their crimes. These men cynically subvert the general good standing of the police force in the community to continue dealing drugs. As a result, their true identities are not immediately apparent to the world outside their group. Witness also pays tribute to the family group, showing the strength of family bonds under stress. Book, for example, worries about his sister’s fatherless children and her uncertain lifestyle because he understands the value of stable family life. Elaine is generous to her brother, offering her car to him and hospitality to Rachel and Samuel when he needs a place for them to stay. She wants him to settle down and find happiness. Eli and Rachel are full of concern for Samuel and show their love for the child when he is in danger through their Insight English for Year 12  © Insight Publications 2007 4 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging instinctive embraces. The ideas of home and intimacy are important, suggesting that there is no other group that quite fits your needs and knows you as well as your family. The experience of belonging to a family transcends culture and Weir shows, especially through the character of Samuel, that it is a social group which helps to form the individual’s identity at crucial moments. Discussion questions †¢ †¢ Why is Book not even tempted to join the corrupt officers and become rich by dealing drugs? In what ways do Elaine and Rachel show that motherhood and family are important aspects of their identity? Choosing not to belong The choice to leave a family, religious or political group can be a painful one, carrying with it a feeling of disloyalty. Sometimes, however, rejection can occur pre-emptively, when the choice is made not to join a particular group. In order to live out their beliefs, people may decide to reject the life offered by mainstream society in favour of belonging to an exclusive group. The Amish tenaciously retain their traditional way of life by cutting themselves off from virtually all that the modern world has to offer. Television, radio, cars and farm machinery are absent from their lives and their 19th century clothing styles symbolise their rejection of progress. Eli articulates this best. Be ye separate’, he tells Samuel sternly, quoting the scriptural precept on which the Amish base their lives. This old-fashioned lifestyle is a cause of amusement to the American public, who regard them as an endearingly quaint tourist attraction. However, Weir seems to endorse the Amish way, by showing that they function simply but effectively. Samuel shows Book how the water pump and the grain storage system w ork and there is an air of quiet prosperity about the farms. The film presents the unhurried pace of Amish life almost idyllically, with shots of blue skies and clear water. It is very effectively contrasted with the sleazy Happy Valley nightclub and the dangerous men’s room at Penn Station. Insight English for Year 12  © Insight Publications 2007 5 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging With these contrasting landscapes and social groups, Weir challenges the idea that progress and modernity are indisputably beneficial. There is visual humour in the shot of the Amish buggy travelling slowly, a long line of traffic in its wake. Weir also contrasts, more seriously, what it means to be a single mother in both of these groups. Rachel is supported by a loving, stable community while Elaine’s crowded, chaotic house plays host to a succession of lovers and surrogate fathers for her boys. To choose separation from a volatile and dangerous world brings its own security. Weir compares the relative value of the two communities with definite nostalgia for a simple way of life no longer possible for most people in modern Western societies. It is not easy to gain acceptance into an exclusive group. We hear Eli’s concern when the wounded Book is brought to hide at the farm. Contact with the ‘English’ is dangerous in his eyes. The solemn Amish folk smile at the spectacle of Book dressed in the ‘plain’ clothing of the community. It is his embarrassed scowl as much as the ill-fitting suit that clearly shows he does not belong. Book and his hosts both understand that he is putting his real identity, purpose and police officer’s ways on hold for a while. Only his carpentry skills, which the Amish regard as useful, win him acceptance among the men. As Rachel tells him, ‘Whacking’s not much use on a farm’. Eli’s final blessing has been hardwon. ‘You be careful out among them English’, he tells Book. This shows that he sees the policeman as changed and vulnerable, not quite Amish but no longer really belonging to the dangerous outside world. When the three corrupt police officers, a secretive clique in the police force with their own sense of exclusivity, descend on the community, the Amish are forced to confront the evil that they try to avoid. They bring no weapons when they run to answer the alarm bell, just their belief in the power of good to overcome evil. When Schaeffer fumbles for his identity card the Amish ignore it. They stare in silent witness at an evil man whose actions, not his status and power, tell them who he is. The film suggests that the Amish community are strong enough to survive the violence and crime that has occurred so close. While they have experienced events unlike any they have previously witnessed, the community remains unaltered and uncompromised. Insight English for Year 12  © Insight Publications 2007 6 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging Discussion question †¢ How may an expanded view of the world and learning more about other groups change people’s understanding of themselves? Belonging to a group and self-sacrifice Belonging to a group may mean subjugating your own desires and opinions for the greater good and goals of the group. If the compromise becomes too great, and the group no longer seems to fit with the individual’s sense of self, a person may choose to abandon the group. Very often, however, this choice seems too frightening, and people settle for the familiar rather than the unknown, comfortable where they belong and ready to accommodate their identity to the group ethos. In Witness, Rachel becomes stifled by the narrow options before her – to continue as a widow or to marry the mild-mannered Daniel. The intrusion of Book, an outsider into their group, forces her to reconsider her position in the community. She faces a strong sexual desire for a man other than her husband. This desire causes Rachel to question the limitations of her ordered, gentle world and to consider the possibility that outside it she could be a totally different person. As a result, Rachel’s manner changes and we see the possible emergence of a more independent woman: she removes her bonnet, the outward sign of her Amish identity, and goes to Book. Such impulses are well under control by the end of the film. The film’s final shots see her returned to her bonnet, positioned in the kitchen, accepting that her place is with the Amish. The decision to join a group may require further choices which may alter the individual’s sense of self. Carter and Book have freely chosen to join the police force. This indicates their values based on their sense of who they are. Each man’s private ethics are publicly expressed in their desire to belong to an organisation that fights crime and seeks justice. However, their exposure to the evil and violence of the criminal world involves a sacrifice of these ethics, manifested in the counterforce they must use to fight crime. When Book manhandles the suspect outside the nightclub we are encouraged, like Rachel, to be appalled by this display of violence. We respond similarly when he excessively beats the mocking tourist. Book is desensitised to violence; it has become second nature for him to rely on violent force to resolve problems. Insight English for Year 12  © Insight Publications 2007 7 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging Those who defy or corrupt the group must be punished by exclusion. The Amish ‘shunning’, which Eli warns Rachel to avoid, would cut her off from the life of the community. If she were judged to have offended their laws by her open attraction to Book she would no longer be able to speak and eat with her people. To be set apart from the group in this way would be unbearable for those who live in such a close-knit community. Denied a secure place in the group that has always nurtured them, they may begin to question their very identity. Total loyalty is required if the group is to keep its integrity. When a group grants power to some of its members so that they can lead, that power may become very attractive. Even among the Amish, the leaders (or Elders) have the authority to make decisions about the lives of other members. We witness their self-importance as they walk under their large umbrellas and leave Eli in the rain. When the power of leadership corrupts those who hold it, the group is used to serve the interests of those who command. This is clearly seen in Witness in the example of the senior police officers, McFee and Schaeffer. They retain only the mask of responsible law enforcement officers. Their murders of the undercover policeman and Carter, and their ruthless pursuit of Book, show they are prepared to abuse their authority in the group for their own gain. In order to profit from drug trafficking, they have sacrificed their ethics and the wholeness of their identity. Discussion question †¢ In what ways can a group be damaged or destroyed when its members’ values or beliefs change? Identity under pressure What happens when your sense of self becomes destabilised? When people enter an unfamiliar culture they often begin to question their own beliefs and customs. How difficult would it be to adopt another culture permanently and how would it affect your own identity? Do we freely choose who we become? Witness shows us how uncomfortable it feels to be displaced from a familiar group, alone and unsupported in a strange community. The film takes the wideeyed Samuel and his mother through the backstreets of Philadelphia. The audience views scenes of sleaze and violence anew, through the horrified eyes Insight English for Year 12  © Insight Publications 2007 8 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging f the Amish woman and her child. Rachel’s prayer over the meal in the hot dog diner shows how out of place she is in secular society. Book’s attack on the young tourist is such unlikely behaviour for an Amish person that it arouses the suspicion of the police. Both Rachel and Book stay true to themselves, reacting to the unfamiliar world around them in ways that ar e consistent with their sense of self – a devout Amish woman and a tough, short-tempered police officer. Their identities have been formed by the groups they belong to; they have internalised the groups’ values. Rachel can no more easily become a modern American woman than Book can become Amish. In the end, the power of their established identities is stronger than their desire to be together. Nevertheless, the film plays with the possibility that Book could live his life among the Amish. His strong attraction to Rachel makes even this hardened Philadelphia cop consider the idea briefly. Just like the audience, he is drawn into the simple world offered by the community, exploring the farm and experiencing nostalgia for a life that Weir presents so idyllically. It provides a potent antidote to his city life. Book is content to work with Eli, make toys for Samuel and adore Rachel silently, almost taking on the role of her dead husband in the household. However, he has few real points of contact with the Amish, apart from his use of hammer and nails. His rage at the irritating tourists shows that he cannot accept the pacifist beliefs of the community. Even when he gulps down lemonade, Book is presented as a man accustomed to grabbing at the pleasures of life. This is contrasted with the small sips taken by the more moderate Daniel. The energy and forcefulness that attract Rachel to Book are the very qualities that make him ill-equipped to truly belong in the Amish community. Book and Rachel yearn for each other. As the song ‘(What a) Wonderful World’ plays on the car radio, Weir intensifies the emotion of the film. They hold each other as they dance, 1950s style, innocently but with terrible longing. There is a moment of crisis in Witness when Rachel is prepared to throw away her world. Having come to love Book, she finds her fundamental values and way of life challenged by her desire for him. The scene in which she is naked symbolises her willingness to set aside all the trappings of her religion and culture in order Insight English for Year 12  © Insight Publications 2007 9 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging to offer him her essential self. It is a measure of Book’s greater worldliness and experience of life that he knows their love is impossible. Although dress signifies identity in Witness, the possibility of false appearances is presented as something to be cautious of. At Penn Station, Samuel approaches the Hasidic man confidently, assuming from his clothes that he is Amish, only to find to his dismay that he is a stranger. In the men’s room, the murdered drug dealer is really an undercover policeman and the murderer is actually a senior police officer. Weir sets up this confusion in the early scenes to suggest that we cannot rely on appearances to judge who and what people really are. Later in the film, we see McFee standing proudly with his citation in the photograph; despite his crimes he presents himself as every inch a police officer in his uniform. We see Book posing as an Amish farmer and Schaeffer identifying himself as a policeman to convince the Amish that he is to be trusted. Weir suggests that it is not always easy to know another person or to see beyond the disguises we present to one another. Clothes or costumes, in this context, may be a distraction from understanding the truth. Samuel seems wise beyond his years when he tells his grandfather that he can tell a ‘bad man’ by his deeds. ‘I can see what they do’, he says sadly. ‘I have seen it. ’ Discussion questions †¢ †¢ Do you think that Book has changed in any way by the end of the film? What future do you predict for Rachel? Points of view on the Context The following discussion topics, writing topics and activities are designed to assist you to develop your understanding of the ideas explored in the Context Exploring Issues of Identity and Belonging. By discussing and considering different responses to the issues raised by Witness, you will learn to articulate your own point of view. Insight English for Year 12  © Insight Publications 2007 10 Article on Witness by Rosemary O’Shea Area of Study 2 Context: Exploring Issues of Identity and Belonging Discussion/writing topics †¢ The Amish have gained more than they have lost by rejecting the modern world. Make a list of all the advantages and disadvantages that their separateness has brought them before you begin the discussion. †¢ There is an old saying, ‘Give me the child until he is seven and I will give you the man’. The statement suggests that adult identity is formed by the experiences of early childhood and implies that people have little control over who they become. Do you agree? †¢ †¢ †¢ Were Rachel and Book wrong to give up their love? Surely love conquers all? What adjustments would Rachel have had to make to join Book’s world? What pressures could make an individual decide to abandon a group that has previously been important in their life? Consider all the groups you belong to. Which of them have you chosen? Which have been chosen for you? Which of these groups has had the strongest influence on the formation of your identity? Activities †¢ In Witness, Rachel tells Book some of the things his sister, Elaine, has said about him in their off-screen conversation. In pairs, create the dialogue of this conversation between the two women as they discuss Book. What other insights into his character could Elaine make? In small groups, research and prepare an oral presentation on groups which are separate from mainstream society for different reasons, such as remote Aboriginal communities, tiny regional towns, prisoners in jail, exclusive religious organisations or people who live in nursing homes. How does belonging to such a group influence the sense of self of its members? †¢ Write the reflection that Book might make on his way home from the Amish community. What would he admire about their way of life? What reasons would he give to convince himself that his relationship with Rachel would never have worked?

Friday, March 20, 2020

Free Essays on Premature Birth

A baby is considered born prematurely if he/she is born more than 3 weeks before his/her due date. About 10% of babies will arrive early. One in eight women will give birth too early-before 37 weeks of pregnancy. The one thing about premature babies is that they have had less time to fully develop and mature in the womb. Preemies are more often at an increased risk of medical and developmental problems and one of the biggest is underdeveloped lungs. If you go into labor early, your doctor will try to delay your baby’s birth. The longer the baby stays in the womb it is giving your baby’s lungs a better chance of becoming more mature. The outlook for premature infants has improved dramatically in recent years. Babies now born as early as 23 weeks now have a good survival chance because of the great advances that has been made for the care of premature infants. We all know that it is best for a baby to stay in the womb for as long as possible to being full term, but being able to recognize the signs of premature labor may help you prevent your baby from being born too soon. The following signs and symptoms can occur as early as four months before you are due to delivery: * regular contractions of your uterus * light vaginal spotting or bleeding * menstrual type or abdominal cramps * low dull back pain * watery discharge from your vagina, this may be amniotic fluid, if so then it is a sign that the membranes around your baby have ruptured * a feeling of pressure in your pelvis as if your baby is pressing down If you at all suspect your in premature labor but yet you have not had a watery discharge, drink two or three glasses of water and then lie down on your left side. This will help improve the circulation to your uterus. About half of the women who go into labor early do so for unkown reasons or you may also have a medical condition that will contribute to the onset of early labor. Some of... Free Essays on Premature Birth Free Essays on Premature Birth A baby is considered born prematurely if he/she is born more than 3 weeks before his/her due date. About 10% of babies will arrive early. One in eight women will give birth too early-before 37 weeks of pregnancy. The one thing about premature babies is that they have had less time to fully develop and mature in the womb. Preemies are more often at an increased risk of medical and developmental problems and one of the biggest is underdeveloped lungs. If you go into labor early, your doctor will try to delay your baby’s birth. The longer the baby stays in the womb it is giving your baby’s lungs a better chance of becoming more mature. The outlook for premature infants has improved dramatically in recent years. Babies now born as early as 23 weeks now have a good survival chance because of the great advances that has been made for the care of premature infants. We all know that it is best for a baby to stay in the womb for as long as possible to being full term, but being able to recognize the signs of premature labor may help you prevent your baby from being born too soon. The following signs and symptoms can occur as early as four months before you are due to delivery: * regular contractions of your uterus * light vaginal spotting or bleeding * menstrual type or abdominal cramps * low dull back pain * watery discharge from your vagina, this may be amniotic fluid, if so then it is a sign that the membranes around your baby have ruptured * a feeling of pressure in your pelvis as if your baby is pressing down If you at all suspect your in premature labor but yet you have not had a watery discharge, drink two or three glasses of water and then lie down on your left side. This will help improve the circulation to your uterus. About half of the women who go into labor early do so for unkown reasons or you may also have a medical condition that will contribute to the onset of early labor. Some of...

Wednesday, March 4, 2020

Is Trucking the Best Job for You

Is Trucking the Best Job for You Do you ever fantasize about quitting your job and finding a career on the open road, with just your thoughts and the radio to keep you company? If so, you’re not alone- and it may not be as far-fetched a career plan as you might think. Growing OpportunitiesMuch of the U.S. economy depends on goods finding their way to warehouses and stores all over the country- and in many cases, those goods are transported by long-haul tractor-trailer truck drivers. Fast delivery is becoming a major selling point for online retailers like Amazon and big-box stores like Wal-Mart and Target, which makes professional truckers an  important part of satisfying customer expectations.Truck drivers are a crucial part of an ever-expanding supply chain: by 2022, the U.S. Bureau of Labor Statistics projects that the demand for heavy and tractor-trailer drivers will grow by as much as 11%.The LegworkThere are hurdles to a career in trucking- as tempting as it sounds, you can’t just show up, stan dard driver’s license in hand, and expect to drive a big rig to Ohio. All states require a specific Commercial Driver’s License (CDL) to operate heavy trucks and tractor-trailers. Additionally, most trucking companies require a high school degree and completion of a professional truck-driving training program.There are also personal considerations. Are you willing to be away from home for days or weeks at a time? Do you have the time-management skills to meet rigorous delivery schedules in all weather, on holidays, or on your birthday? Being a truck driver requires a strong personal commitment as well as a professional one.Hitting the RoadLet’s say you’ve met all these requirements, made the necessary choices, and received the right training and recommendations. You’re ready to pack up your faithful dog and your toothbrush, and seek a trucking job. What’s the best way to do that?You may want to start by researching which trucking companies m eet your goals and your comfort level. Regional trucking companies may be able to offer you jobs closer to home. National trucking companies tend to have the broadest reach and the most access to available trucking jobs.You should also consider whether the company will hire a rookie driver right out of the gate- many companies want their new drivers to have 3 months to a year of driving time before they’ll consider hiring. This may sound discouraging to start (how do I get experience if no one will hire me without experience?), but it’s common in most career paths to start at the bottom by creating/locating opportunities and working your way up.The Money QuestionPerhaps the most important part of any job search is understanding what your salary will be- and can be. Like other fields, trucking offers its lowest salaries to drivers just starting out, especially if you don’t have the driving experience yet. However, you should know that while many industries have a wide gap between starting employees and long-time veterans, truck drivers have a pretty even field once you’re in it.The average starting pay for a truck driver is $13.81/hour, compared to an average of $18.37/hour (approximately $38,200/year) for all drivers. This kind of parity is often a reason people choose to get started in the trucking industry- your pay is not significantly less than more experienced colleagues’.If you’re seeking a career that can be challenging and fulfilling while paying the bills and letting you travel, trucking  could just be the right choice for you. And if you have the ability to find Zen even in the most obnoxious traffic jams, all the better!