baroque art1 essays

baroque art1 essays The baroque has been called a theatrical style, one that deals in spectacle, grandeur, and dramatic contrast. Test these concepts in an essay that discusses the baroque as an expression of the Catholic Reformation, Protestant devotionalism, the Scientific Revolution, and the Age of Absolutism. Define your general statements with specific examples. The following essay will discuss the baroque period and how the Catholic Reformation, Protestant devotionalism, and the Scientific Revolution influenced it. The Baroque period generally refers to the years 1600 to1750. Classicism of the Renaissance has been replenished during the Baroque period. During the Baroque artistic period, the exploration of the fundamental components of human nature and the realm of senses and emotions were very crucial. The Baroque era was a very dynamic time that showed an abundance of radiance and color. Artists of this time were passionate and sensual. Their works were many times considered to have an overpowering emotional effect. The superficial form of light was fascinated during this period due to the thoughts of godlike sun or the truth of the Holy Spirit. The Baroque naturalism maintains the religious themes in content. The elements of perception in the Baroque art are how we perceived the natural human figures are in motion through s pace, time, and light. We present and analyze the extent of human actions and passions in all its degrees of lightness, darkness, and intensity. The scientific revolution also had a tremendous impact on art during this time. Scientists started to study the earth and its positioning in the universe. This was a time when the people started take more of an interest in astronomy and mathematical equations. During the time of the Catholic Reformation artists began to challenge all the rules that society has set for artistic design. Artist starting with Parmigianino, Tintoretto, and E ...

The Plague Essays (463 words) - Medicine, Plague, Health

The Plague Essays (463 words) - Medicine, Plague, Health The Plague The novel that I chose to do this report on was, The Plague, by Albert Camus. It is about a plague that hit the European countries in the middle ages. I chose to describe the literary term of parallelism. Here are some following facts about the story's plot that involve parallelism through the novel. The novel begins at Oran where the plague becomes known. The main character, Dr. Gernard Rieux, is a doctor. In the beginning of the story he finds a dead rat on the floor. Even in those times rats were not found dead on the middle of the floor. This was unusual, but he threw out the rat and forgot about it. Eventually the dead rats began to pile into large masses and burned. Soon after there were some people that got very sick, which made Mr. Rieux very curious. These reports of these ill people and the death of the rats were the beginning of the parallelism for this story. Since Bernard was a doctor he was the first to actually attempt to help one of these sick people. Michael was his first patient in this matter. He was the sickest person that the doctor had ever seen. Michael was pale white and vomited often, he hurt so much from the vomiting that he seemed paralyzed. Mr. Rieux tried to help the man the best that he could, but he ended up dying. Michael was the first person to die of this illness. After his death, many cases of this illness were reported widespread. Again more details of sickness and death, this is the parallelism for this novel. As the reports of sickness and death came to inform Dr. Rieux, he tried to comfort and cure the plagued patients. About ninety percent of the people infected had died. He wanted a stop to this plague. Quickly he linked the rats with the people. He knew that the rats began to get sick before the people did. At this time many people had the plague, except for the Chinese visitors. They never were infected. As the plot moves on death, sickness and the plague are still relevant. He studied their behaviors and everyday tasks and learned that they do something that was never often done in these middle ages. Not many people in these days bathed. The doctor began to notice that the people that bathed never got sick. So he asked all of his, still living patients, to take baths frequently. This proved to be the miracle cure for the people. The doctor asked his other fellow doctors to follow the same practice with their patients. The word was spread and the plague was soon wiped out. So as you can see, the literary term of parallelism was deemed very relevant through the ongoing plot. Death, sickness, and the plague epresented the story's parallelism. Albert Camus made parallelism the main literary term for this novel, given away by the title, The Plague.

Potential of virtual currency Research Paper Example | Topics and Well Written Essays - 1000 words

Potential of virtual currency - Research Paper Example The regimes include the rules that are against money laundering, regulations on the electric money transfer, regulations on gift card and also the requirements on financial privacy. Following the growth of technology social networks, and also, gaming sites have also developed. The networks have evolved to offering individual form of currency. It is also worth understanding that the currencies offered by the networking sites circulate in the entire economy. There are various forms of virtual economies such as the closed loop economies; it is involved in the restriction of users to single entities, and the currency is acceptable. It also involves the semi-closed loop; it is a loop that enables the user to use the funds and make purchases from sellers who are defined. Lastly, is an open loop that enables the currency to get applied in unlimited numbers to the retailer (Keith, 2011). Due to  growth on the gaming systems and also virtual economies the gap between virtual systems and the real world has become blurred. Therefore, it is significant that the people involved in the economies to perform various roles. People involved include the government regulators and also the central bank (David et al., 2011). It should also get understood that there are possibilities of the virtual economies to get converted to real world goods, as well as currencies. Questions are arising due to virtual economies becoming similar and also interoperable in the real world economies. There are questions as to whether statutes of the real world such as the transfer of funds, money transmitting and also holding of financial transactions is applicable to the websites and other similar services (David et al., 2011). There are also issues regarding the virtue payments due to the evolution of the virtue economies, and they continue to outpace the regulations of the real world. With the

Insider Trading Essay Example | Topics and Well Written Essays - 500 words

Insider Trading - Essay Example A corporate officer, for instance, who uses information known to him, but not to the public, to purchase or buy securities is generally guilty of insider trading. Exceptions may be allowed for certain transactions which are immaterial or which are reported the United States Securities and Exchange Commission. It must also be noted, however, that the concept of insider trading extends beyond corporate officers and insiders in the technical sense. It also includes people who provide tips to outsiders. This secondary portion of the definition ensures that the primary subjects of the law, corporate officers and fiduciaries, cannot escape punishment by secretly providing information to outsiders and non-fiduciaries (Insider Trading, 2006). The causes of insider trading are quite easy to understand. To illustrate, a corporate officer knows when the value of the corporation is going to increase or decrease. Perhaps there are secret negotiations for a takeover in which share prices are going to increase. He can sell his securities in order to maximize his profits or minimize his losses.

Financial Management - Ratios comparision Essay

Financial Management - Ratios comparision - Essay Example This ratio indicates the financial structure of the enterprise. In other words the ratio is a barometer to reveal how the assets of the enterprise have been financed. Total Owings (Debts) include long-term debts and current liabilities, whereas Total Assets consists of both fixed and current assets. The ratio measures the total assets financed by outside debts. In 2006 47.54% of total assets of Bloodstone Ltd. Were financed through total owings, both long term as well current liabilities; where as in 2007 dependency on owings for assets financing has marginally gone up to 48.38%. The situation of Blooodstone Ltd.is little better than Garnet Plc., half of whose assets are financed through owings The ratio measures the incremental sales over previous year sales. The formula is to divide the absolute increased value of sales by total sales of the previous year and express the increment as percentage over previous year’s sales. Blood Stone Ltd. has attained a 15% growth in sales in the year 2006 over the sales of 2005. On the other hand such growth is only 8% for Garnet Plc. Even assuming both the companies in the same industry there may be a variety of reasons for such increased growth for Blood Stone Ltd., like: a) Increased value of fixed assets in the year 2006 as compared to 2005 suggests the new fixed assets have been manage effectively in the contribution of growth in sales. There may have been increase in sale outlets and in areas where there is no or negligible competition. b) Debtors have gone down to â‚ ¤1050 in 2006 as compared to â‚ ¤1,100 in 2005. This implies that the emphasis was on cash sales either by reducing the sales prices per unit or by providing cash discounts. There is also a possibility that certain incentive plans might have been introduced or there was better credit control. Bloodstone Ltd.’s PBIT ratio has remained more or less constant during 2005 and 2006. In 2006 it was 4.67% as compared to 4.5% in 2005.

Supply Power To A Fluorescent Lamp Engineering Essay

Supply Power To A Fluorescent Lamp Engineering Essay The following report contains the steps taken in designing, constructing and testing of a basic electrical system used to supply power to a fluorescent lamp. This report summarizes the method used to calculate the desired circuit parameters. Also, the design was implemented to achieve the required design objectives. INTRODUCTION An engineering approach was used in this design project and as such, it consisted the design, construction and testing of a basic electrical system used to supply power to a fluorescent lamp. The power factor of the system needed to be corrected to increase efficiency and this was explained in detail. Due to the high level of risk involved in this design project, precautions needed to be taken. Laboratory protocol, industry standards, codes of practice and occupational safety protocols was taken into account during this design project. Course material from ECNG 1015 Introduction to Electrical Energy Systems, ECNG 1006 Laboratory and Project Design I and ECNG 1016 Mathematics for Electrical Engineers was used in this design project. In this report, all necessary mathematical models, and diagrams will be detailed. Also, the steps used to improve the power factor of the relay system will be accounted for as well as the main processes implemented in the system. Background Theory What is a fluorescent lamp? According to Sams F-Lamp FAQ, fluorescent lamps are a type of discharge tube similar to neon signs and mercury or sodium vapour street or yard lights. The Different Types of Fluorescent Lamp Fixtures There are basically three different types of fluorescent lamp fixtures. The three most used fixtures are listed as follows; 1. Instant Start 2. Rapid Start 3. Preheat fixtures. Instant start Instant start fixtures require a high voltage to be applied to the lamp to cause it to work. This high voltage must be above the specified voltage required for the lamp to light. This high voltage is required since the resistance of the gas may be high. Thus, the voltage being applied will force the gas to conduct and hence light. Sometimes, a potential difference is required to create a potential difference between instant start fixture and the lamp cathodes. This potential difference causes ionization to occur and this reduces the resistance of the lamp. The initial current which flows through the lamp causes the light to shine at maximum brightness. After the lamp turns on, the instant-start ballast will immediately regulate the voltage and current to the operating conditions of the lamps. OR Once current starts flowing through the lamps, the lamps illuminate at close to their full brightness. After a successful start, the instant-start ballast will immediately regulate the voltage and current down to the normal operating levels (QUOTE). The average lamp life of an instant-start fixture is much shorter than that of a rapid start fixture. This is due to the fact that the instant-start fixtures use more energy than a rapid start fixture. It is also more efficient as it has a very efficient ballast. Caution must be used with respect to instant-start lamps in areas which utilizes occupancy sensors. Rapid start Rapid start is the name given to fluorescent fixtures with two or more lamps. When using this type of system, no starter switch is available for use. The ballast is used to maintain a steady current flow in the lamp at all times. In order for the lamp to start, a capacitor is used to ionize the gas, hence reducing the resistance of the flow of the gas. The ballast allows the current in the lamp to flow when the gas is ionised. This current flow causes the lamp to glow dimly and also heats the gas. This heating of the gas generates light and this light is used to further ionize the gas. The ballast is also used to increase the start up process of lighting the bulb. All these process aid in decreasing the resistance of the gas and increasing the current flowing through the lamp. As brightness of the bulb can be thought of as directly proportional to the current flow. When the arc discharge occurs, the lamp is turned on and light is produced. However, the light given off wouldnt be as bright since it takes a certain amount of time to ionise the gas. Hence, a couple of seconds would be required to achieve maximum brightness. Applications that require constant turning on/off are best suited with rapid start lamps. Their long life and their ability to dim when required make them ideal for certain applications. However, these lamps consume power even when the filaments have burned out. Preheat fixtures A preheat fixture lamp is utilized in this project. Preheat fixtures usually consist of a starting circuit which allows current to flow through the cathodes to warm the filaments. A high voltage is sent through the tube and this creates an arc across the mercury vapour. This results in the atmosphere inside the tube to heat up and thus, electron activity from the gas increases. The electrons move rapidly through the tube and they carry the current as they move. The starter switch opens when the circuit is preheated for a short period of time (Henkenius, 2007). Preheat fixtures are preferred as they use low cost performance phosphors. In using pre heat fixtures, the electrodes are damaged faster than other fixtures resulting in shorter life span. The type of ballast used in pre heat fixtures is either magnetic or resistive. It is recommended to avoid the use of pre heat fixtures as the maximum energy is not used. Existing Types of Fluorescent Tubes The following are some of the different types of fluorescent tubes; T-5 This type of fluorescent lamp is extremely powerful. It boasts low maintenance, low disposal costs and it allows for smaller fixtures to be used. These types of lamps have an average life of 35,000 hours based on 12 hours per start. T-8 This type of fluorescent lamp is used mainly for its sustainability. It boasts long life, a low level of mercury and it is energy efficient. The Philips T8 32W Extra Long life lamp and the Philips T8 25W will on average last longer than a standard 4T8 32W lamp. T-12 This type of fluorescent lamp provides long life and high performance. It also comes in different sizes, shapes and types. An average life of 24,000 hours, 85 CRI and the highest lumen output are the features of this lamp. T-16 This type of fluorescent lamp is usually 60 inches long and has a diameter of 2 inches. A starter is needed for this type of lamp as it is a preheat lamp. NEOLITEà ¢Ã¢â‚¬Å¾Ã‚ ¢ low-mercury This type of fluorescent lamp is arguably one of the smallest fluorescent lamps ever made. This NEOLITEà ¢Ã¢â‚¬Å¾Ã‚ ¢ low-mercury lamp has an average life of 10,000 hours and its brightness is rated at 70 lumens per watt. Dim Lights This type of fluorescent lamp can be dimmed to about 20% of their full brightness. Thus, this type of lamp is considered an energy saver. Circle Tube This type of fluorescent tube uses a 4-pin connector. It is on average 8 to 12 inches in diameter. U-tube This type of fluorescent tube is shaped like a U as it name suggests. A tube which is bent into this U shape is much brighter than a normal tube of similar dimensions. Requirements for the Operation of Fluorescent Lamps The principles of operation of the system gave insight into some of the requirements needed for the operation of fluorescent lamps. These requirements are; An electrical current is required to flow through the tube to power the system. A ballast is required which controls the current flowing through the system and it provides the voltage kick which creates the arc in the tube. A starter switch is needed to turn on/off the system. Turning off the system cuts the current flowing to the ballast, hence turning the lamp off. A relay is needed as its contacts control whether the circuit is open or close. In works together with the starter switch to control the lamp. Advantages and Disadvantages of Different Systems The Ballast The ballast is considered one of the most important components of a fluorescent lamp, as it is used to start the lamp. Also, the current flowing through the circuit is controlled by the ballast as it regulates current flow. The ballast is extremely important in the circuit, as it corrects the power factor which increases the efficiency of electrical power consumption (quote). A fluorescent lamp without a ballast is considered a short circuit. Thus, there is a lot of current between the filaments and this causes the filaments to vaporise or the bulb to explode. Thus, the ballast can be seen as a core component in the fluorescent system. There are typically two types of ballast used in fluorescent lamps. They are listed as follows; Inductive Ballast Electronic Ballast Inductive Ballast An inductive ballast connected with a starter is considered a series inductor. This type of ballast provides an inductive kick to jump start the lamp. This occurs when the current flowing through the ballast is interrupted. When this happens, a voltage is provided across the cathodes which are used to ionize the gas in the tube hence keeping the filaments hot. According to www.infralight.com.au/ballasts.html, the inductive ballast has two benefits. They are listed as follows; Its reactance limits the power available to the lamp with only minimal power losses in the inductor The voltage spike produced when current through the inductor is rapidly interrupted is used in some circuits to first strike the arc in the lamp. There are however disadvantages of using an inductive ballast. They are listed as follows; The life span is significantly reduced An A rated ballast will hum softly while a D rated ballast will hum loudly. According to www.freepatentsonline.com/y2008/0019113, the number of ballasts and their sound rating determines whether or not a system will create an audible disturbance which an inductive ballasts does. Excessive heat is produced when in use Electronic Ballast According to www.ehow.com/about_6131466_electric-ballast-definition, An electrical ballast is a device that is used in gas discharge lighting systems to regulate the flow of current and to provide adequate voltage for the lights to function properly. The electronic ballast is typically preferred because it is more efficient than an inductive ballast. Furthermore, an inductive ballast requires a starter switch, less heat is lost, lamps do not flicker as often and the overall dimensions are smaller. However, the electronic ballast has its disadvantages. When it is used in parallel, there is an increase in losses within the circuit. Sometimes, odd current waveforms are drawn due to a high current. Also, there is interference from the ballast and tubes in the circuit. The electronic ballast is not used in the pre heat fixture system. Thus, it would have no effect in this design as an inductive ballast will be used. Operation of the System Inside a glass tube, there exists a pair of electrodes, a drop of mercury and some inert gas sealed at an extremely low pressure. The electrodes are sealed at each end of the tube. The electrodes are in the form of filaments which for preheat and rapid or warm start fixtures are heated during the starting process to decrease the voltage requirements and remain hot during normal operation as a result of the gas discharge (Goldwasser, 1999). The inert gas is usually argon. Phosphorous material line the inside of the tube. This material is used as it produces visible light due to ultra violet radiation upon it. A relatively high voltage is required to initiate the discharge of the mercury/gas mixture. After this discharge, a relatively lower voltage is required to maintain it. The current which flows to the electrodes creates a voltage which acts across the electrodes. The electrons in the electrodes disperse from one side of the tube to the other. These excited electrons create energy and this energy changes some of the mercury to a gas. Electrons from mercury are special as they release photons which can be seen as ultraviolet light. Since the wavelength of ultraviolet light is so small, it cannot be seen by the naked eye. The ultraviolet light is made visible through the use of the phosphor powder coating. Photons released from the electrons are incident upon the phosphor coating and this causes the phosphors electrons to emit energy as it changes energy levels. This energy is usually given off in the form of heat. According to home.howstuffworks.com/fluorescent-lamp2, in a fluorescent l amp, the emitted light is in the visible spectrum the phosphor gives off white light we can see. Manufacturers can vary the color of the light by using different combinations of phosphors. In a fluorescent lamp, the emitted light is in the visible spectrum the phosphor gives off white light we can see. (Harris, 2009) Switch The switch system being used in this design project is the normally open and normally close switch. This switch controls the relay system as it closes the circuit when flipped. The lamp will then be turned on, as current is being supplied to the circuit. Starter Starters in pre heat fixtures are either automatic or manual and are used to light the lamp. When flipped, a voltage is applied to the circuit and this causes the lamp to light. A few things occur when the switch is flipped. Firstly, a current flows through the filaments and this causes the contacts to heat and open. This interrupts the current flow which in turn lights the bulb. The inductive ballast comes into play at this point. It regulates the current flowing through the circuit as the fluorescent tube now has a low resistance as it is lighted. The starter used in preheat fixtures can be considered an on/off switch. It controls the period of time when the circuit opens/closes. As it is opened, the voltage causes ionisation of the mercury vapour due to the movement of electrons across the tube. The starter is very important as it determines whether the lamp flickers or not. This flickering can be attributed to the steady flow of electrons between the two filaments. Figure :How starter works Design process Project plan A project without any guidance or sequence is useless. Thus, a time management system was put into place in order to complete this design project. Before a system could be implemented, the project description must be known as well as the duration of the project. The design brief which entails everything the student needed to know about the project is stated in the following; Students are required to design and build an electrical system in order to power a small fluorescent lamp. The system must incorporate an on/off switch utilizing a 110V relay (8-pin relay and base, 110V) to power the fluorescent lamp assembly (1X20 regular ballast type 110V fluorescent fixture). Students are required to; Understand the load: its operation and existing types of fluorescent lamps Determine the systems required for the operation of the lamp (use of an inductive or an electronic ballast Develop a mathematical model for the relay based on the principle of operation of the vertical-lift contactor. Design a start/ stop switch utilizing the relay to power the fluorescent lamp and discuss the importance of this switch in terms of safety. Determine if the magnitude of the inductance is sufficient to light the fluorescent lamp. Determine the magnitude of the force required to activate the relay and the load current to be supplied to the fluorescent lamp. Measure the existing power factor of the load and improve the power factor to at least 0.9 lagging. Investigate the effect of the fluorescent lamp assembly on the power system. Supply a detailed explanation of the operation of the system using the system phasors to support your discussion. QUOTE ELEARNING Students are required to apply the knowledge gained from ECNG 1015 Introduction to Electrical Energy Systems as well as the laboratory exercises that were performed during the semester. Consideration must also be given to laboratory protocol, industry standards, codes of practice, occupational safety protocols and risk assessment in undertaking this project. 3.2 Time Management Schedule The following table illustrates the time management system used to complete this design project; Week # Designated Tasks Completed 1 Thorough research was done on fluorescent lamps to better understand the system. A Safety and Risk Assessment was done with respect to the design project. 2 Specification sheets for acquired after collecting the required information from the ballast, relay, etc. 3 The start/stop switch was designed and used together with the relay to power the fluorescent lamp. Key parameters were measured from the circuit. 4 A mathematical model of the relay system was determined. Using this model, the force required to activate the relay was determined. Also, the load current to get the fluorescent lamp to light was determined. 5 The existing power factor was measured and it was improved to 0.9 lagging with the use of a capacitor. 6 Proof read report and get accustomed to fluorescent lamp system in preparation for oral exam. Table 1 showing Time Management System used to finish the design project. Development of the Mathematical model of the Relay A mathematical model of the system must be done as the system is required to operate within specified parameters. Firstly, a model of the relay was done to determine it parameters. The following indicates how this system was modelled; Amperes Circuital Law states that the line integral of the magnetic field intensity, H, around a closed path in the magnetic field is equal to surface integral of the current density, J, over any surface bounded by the closed path (Defour, 2011). This implies; The magnetomotive force is a product of the number of turns in the coil and the current flowing through the coil. => [Eqn 2] [Eqn 3] Since we are using a ferromagnetic material, the magnetic field intensity H, can also be stated as; [Eqn 4] [Eqn 5] [Eqn 6] and F are constant in the above equation. This implies that is directly proportional to F, providing that all variables above remain constant. [Eqn 7] The above equation is similar to ohms law. Hence, the reluctance in this circuit can be treated as the resistance of the system, the force as the voltage through the circuit and as the current flowing through the circuit. Figure : Magnetic equivalent circuit Reluctance can also be stated as; [Eqn 8] If current is applied to the coil in the circuit above, the magnetic flux would vary. This change in magnetic flux is given by the equation; [Eqn 9] The above equation gives the change in magnetic flux for one turn of the coil. Hence, for N turns, the following equation is used; [Eqn 10] [Eqn 11] [Eqn 12] When equations 11 and 12 are substituted for and F, the following equation is formed; [Eqn 13] The inductance of the coil remains constant in the above equation. Hence, the flux linkage through the coil is directly proportional to the current flowing through the coil. [Eqn 14] When equation 13 is substituted into equation 14, the following equation is formed; [Eqn 15] However, V can be determined as the potential difference across the coil, R as the resistance of the coil and e as the emf of the coil; [Eqn 16] However, [Eqn 17] Figure : Electrical equivalent circuit The above circuit can be used to measure power in the circuit. Power is the product of current flowing throught the circuit and the voltage across the circuit. Multiplying equation 16 by the current flowing through the circuit gives the power as seen in the following; [Eqn 18] The following equation states that the energy supplied from the source to the field; [Eqn 19] The law of conservation of energy states that energy is always conserved. The following equation shows this conservation of energy; [Eqn 20] Flux linkage across the coil can be thought of as constant. This is flux linkage is assumed as the displacement of the armature occurs rapidly. Using Faradays law of Induction, the coil does not have an emf induced across it as ÃŽÂ » is constant. [Eqn 21] The above equation implies that there is no energy flowing from the supply source to the coil. As such, equation 20 can be stated as follows; [Eqn 22] Taking into account the law of conservation of energy and the above equation, some energy must be lost from the magnetic field to the mechanical system. When a curve is drawn, the area under the curve illustrates the magnetic field energy lost to the system. [Eqn 23] [Eqn 24] As varies, the energy lost is supplied by the coupling field. The following equation states the energy lost; [Eqn 25] => [Eqn 26] When equation 26 is substituted into equation 24, the force can be determined as follows; [Eqn 27] When equation 14 is substituted into equation 27; [Eqn 28] Consideration of System Requirements Determination of the magnitude of inductance required to light the Lamp Since an inductive ballast is used in this fluorescent lamp system, it has a certain amount of inductance and resistance. Thus, the ballast can be considered as an RL circuit. The following diagram shows the equivalent circuit for the ballast; Figure : Equivalent circuit for the ballast The following equation is used to calculate the impedance of the circuit relay; Determination of the magnitude of inductance when armature is turned on/off Coil Inductance with Armature Off The following equation is used to calculate the impedance of the circuit relay; Coil Inductance with Armature On Deenergize The following equation is used to calculate the impedance of the circuit relay; From the specification sheet, the inductance of the coil was specified as; Inductance of Coil with Armature Off at 120V = 15.04H Inductance of Coil with Armature On at 120V = 7.19H The calculated values for the inductances vary significantly. This can be explained by taking into consideration the tolerance levels associated with the rated current. Also, the reaction time of the was slightly off and this resulted in a different current being taken than the actual current value. Determination of the load current required to activate the relay To determine the minimum current required to activate the relay, an analog voltmeter was used in series with the potentiometer. As the resistance of the potentiometer is not fixed, it was used to determine when the relay would activate. The resistance was varied and just as the relay was activated, the voltmeter was used and the minimum current required to activate the relay was determined. The load current was determined as Determination of the force required to activate the relay The length of the air gap was determined to be approximately 1mm. The minimum current required to activate the relay was determined as Using the specification sheet, the inductance of the coil was determined; Inductance of Coil with Armature Off at 110V = 13.38H Inductance of Coil with Armature On at 110V = 5.69H The following equation was used to determine the force required to activate the relay; Thus, the force required to activate the relay is 1.03N. Determination of key circuit parameters Parameter Unit Value Voltage across relay V 99.5 Min. current to turn on the relay mA 21.8 Resistance, R ÃŽÂ © 1.464k Coil Inductance (Armature off) H 13.38 Coil Inductance (Armature on) H 5.69 Length of Air Gap m 0.001 Inductance of Ballast H 363.82 Parasitic Resistance of Ballast ÃŽÂ © 339.8 Table 3 showing key circuit parameters. Design of start/stop switch Relay A relay is basically a circuit which is used to control/operate another circuit. The relay can be described as an 8-pin relay and base. A coil is located within the relay and it produces a magnetic field when current flows through it. This field causes a contact to change from its original location to another resulting in the circuit being opened or closed. The relay together with the starter was used to power the fluorescent lamp. The following diagrams illustrate the 8-pin arrangement of the relay used; Figure : Arrangement of the 8-pin relay used The above diagram on the left shows that this type of relay is a double pole double throw (DPDT) type relay. The double pole states that two contacts are closed while the double throw states that there are two different paths of conduction within the relay. In this relay system, there are two switches being manipulated. When a voltage is dropped across contacts 2 and 7, a magnetic field is created within the relay. For this magnetic field to be created, the coil in the relay becomes energized and this produces the magnetic field which in turn manipulates the contacts. Contact 1 connects to contact 3 and contact 8 is connected to contact 6. Also, as seen on the diagram, contacts 4 and 5 remain normally closed until activated. The relay is significant in this design project as it controls the current flow. Thus, no large current is exposed to any personnel. (NOT SURE IF TO PUT TRADEMARK) Switch The following diagram illustrates the circuit used to design the start switch; Figure : Schematic Diagram of Circuit Used The switching circuit has three main switches; Normally open switch (NO) Normally closed switch (NC) Start switch The normally open switch indicates whether or not current flows through the circuit. When this switch is flipped, the contacts are connected allowing current to flow. The switch being used must be pushed down in order to complete the circuit to allow current to flow. The normally closed switch will allow current to flow through the circuit normally. In contrast to the normally open switch, when the normally closed switch is pushed, the contacts become disconnected, interrupting the current flow. The start switch is used to turn on/off the fluorescent lamp. If the contacts are connected, then current will flow. Thus, when the start switch is flipped, the fluorescent lamp will be turned on and hence light is given off. In this design project, the normally open and normally closes switches were placed in series with the power supply and terminals 2 and 7. Contacts 1 and 6 were placed in parallel with the normally open switch as shown in the above figure and contacts 1 and 6 were placed across the normally closed switch. When the magnetic field is created in the coil, the contacts in the relay change position and connect to contacts 3 and 6. This configuration was used as the normally open and normally closed switch determines whether the fluorescent lamp is turned on/off. When the normally open switch is pushed, the circuit is closed and the fluorescent lamp lights. When the normally closed switch is pushed, the circuit is open and the fluorescent lamp is turned off. Explanation of the System The voltage rms of the system was determined to be 117.5V. The real power of the system was determined to be 22.5W. The rms voltage determined is equivalent to the phasor voltage of the system. Hence, the phasor current can be determined as follows; The supply voltage V, is calculated using the following equation; Since this is a purely inductive load, the angle at which the current phasor lags the voltage phasor is determined as follows; Hence, the voltage phasor is determined as follows; The current flowing through the lamp is considered as the real current of the apparent current. The following equation is used to calculate this lamp current; The reactive current flowing through the lamp is known to be out of phase with the supply voltage by an angle of . This reactive current was calculated using the following equation; The real current calculated above is placed on the horizontal axis. Hence, it is seen that the voltage phasor is in phase with this real current. The following diagram illustrates the relationship associated with the apparent, reactive and real currents; Figure : Phasor Diagram for System without capacitor A capacitor was used in the design to correct the power factor to at least 0.9 lagging. This capacitor does not affect the power given off by the motor in the system and as such, the current is constant. However, as this capacitor was added, the current from the source decreased when compared to the first current attained. The fluorescent lamp still requires a steady current flow to maintain the specified power. Hence, a current also flows through the capacitor. The system was required to be designed with a power factor of at least 0.9 lagging. Thus; It should be noted that the current flowing through the capacitor reduces the reactive current. Taking into account this corrected power factor, the following diagram illustrates the phasor diagram for the uncorrected power factor, corrected power factor and the capacitor current; Figure; phasor diagram showing currents with the inclusion of a capacitor As stated previously, with the inclusion of the capacitor, a new current will flow throught the system. This current is determined as follows; As seen from the phasor diagram above, form a closed loop. Using Kirchhoffs Current Law, the following equation was used to determine the current flowing through the capacitor; Futhermore; Hence, the capacitor need to correct the power factor to at least 0.9 lagging can be determined as follows; The capacitor determined above is significantly different from the value used. This can be explained by considering that various power losses occur within the system. Also, this capacitance was calculated using theoretical values and not values obtained in the lab. Hence, there would be a difference. From the above figure( phasor diagram for both power factors),

Symbolism and Loss of Identity in The Handmaids Tale by Margaret Atwoo

Symbolism and Loss of Identity in The Handmaid's Tale by Margaret Atwood In Margaret Atwood's The Handmaid's Tale, Offred recounts the story of her life and that of others in Gilead, but she does not do so alone. The symbolic meanings found in the dress code of the women, the names/titles of characters, the absence of the mirror, and the smell and hunger imagery aid her in telling of the repugnant conditions in the Republic of Gilead. The symbols speak with a voice of their own and in decibels louder than Offred can ever dare to use. They convey the social structure of Gileadean society and carry the theme of the individual's loss of identity. All the women in Gilead wear color-coded uniforms. The colors parade their social status and/or role in the reproductive process. The 'Aunts' who run the Rachel and Leah Re-Education Center wear brown; they are responsible for the indoctrination of the handmaids. The 'Marthas,' who wear green, are the servants. The 'Wives' wear a type of Virgin-Mary blue, which signifies their inability to bear children. The handmaids wear red robes and white peaked hats which resemble nuns' habits. Thus, they personify a religious sacrifice; they are like "temple prostitutes doomed to a kind of purdah in perpetuity" (Rigney 117). In addition, the red color of their clothing symbolizes their fertility. The color-coded uniforms that the women wear does more than just signify their functions. Along with the names/titles of characters, they symbolize the individual's loss of identity. No distinguishing mark of a woman is considered; rather, she is lumped with a group in which she is defined only by her social and reproductive function. Essentially, the color-coded uniforms strip each woman of her i... ...litical enemies. The foul and suffocating air of Gilead symbolizes the claustrophobia as well as oppression of its inhabitants (Rubenstein 109-110). In The Handmaid's Tale some symbolic tools such as dress codes and characters' names reflect the social standings of individuals in the Gilead society. These same symbols and others such as the mirror draw attention to the loss of individual identity, a theme present throughout the novel. Still others like smell or hunger convey the atmosphere&emdash;both physical and psychological&emdash;in Gilead. Whatever their different purposes may be, the symbolic devices achieve the same result: they enlighten the reader on dangerous social tendencies and compel him/her to take action in order to prevent the outcomes they depict. Works Cited Atwood, Margaret. The Handmaid's Tale. Anchor Books: New York, New York, 1985.