Response paper Essay Example | Topics and Well Written Essays - 250 words - 27

Response paper - Essay Example The author also says that there were many continuations of the Algerian War found in the modern French society (McCormack 200). The Algerian War in history terms shows parts of the present in relation to its sequels. I believe the Algerian War memories are important in understanding the modern French society. The Algerian war memory has been reserved while the Indo-China conflict has been truly out of the memory, as it does not reappear in the present. The repression of the memory is unhealthy for the French community as it results in repetition of old divisions. It prevents a peaceful mind from existing and brings about the injury produced by painful memories (McCormack 220). Essentially, the commemoration of the Algerian War events should be perceived as an opportunity for the French administration to show their readiness to the Fifth Republic to identify the problematic facets of its history. The French government must generate a report through the creation of a commission to gather evidence and facts about the Algerian war. Great work needs to be done if France is to conquer the divisions in the French society that were inherited from the

Overpopulation is a Real Challenge Essay Example | Topics and Well Written Essays - 250 words - 165

Overpopulation is a Real Challenge - Essay Example This short piece of work differs with Professor Ellis. Â  Professor Ellis acknowledges that the size of the earth is fixed. However, the point of disagreement is that there is no need to exploit more lands as the ones already in use and technological innovations can sustain the growth in population. This is totally untrue because, despite the level of technological innovations and inventions, the lands have their limits. According to the SUNY College of Environmental Science and Forestry, overpopulation is a real threat to humanity as it has the potential to wipe out the entire mankind. Research in this institution has shown that the cumulative effects of overpopulation would be disastrous given the unforgiving character of Mother Nature (SUNY College of Environmental Science and Forestry). Sustainability can only be achieved if the population growth rate is matched by the growth rate of resources. In this case, there is need to increase the acreage of lands under cultivation so as to match population growth rate and consequently check overpopulation.

Load Flow Analysis For Electricity Supply Engineering Essay

Load Flow Analysis For Electricity Supply Engineering Essay Power flow studies, commonly referred to as load flow, are essential of power system analysis and design. Load flow studies are necessary for planning, economic operation, scheduling and exchange of power between utilities. Load flow study is also required for many other analyses such as transient stability, dynamic stability, contingency and state estimation. Network equations can be formulated in a variety of forms. However, node voltage method is commonly used for power system analysis. The network equations which are in the nodal admittance form results in complex linear simultaneous algebraic equations in terms of node currents. The load flow results give the bus voltage magnitude and phase angles and hence the power flow through the transmission lines, line losses and power injection at all the buses. 1.1 BUS Classification Four quantities are associated with each bus. These are voltage magnitude, phase angle ÃŽÂ ´, real power P and reactive power Q. In a load flow study, two out of four quantities are specified and the remaining two quantities are to be obtained through the solutions of equations. The system buses are generally classified into three categories. Slack bus: Also known as swing bus and taken as reference where the magnitude and phase angle of the voltage are specified. This bus provides the additional real and reactive power to supply the transmission losses, since there are unknown until the final solution is obtained. Load buses: Also know as PQ bus. At these buses the real and reactive powers are specified. The magnitude and phase angle of the bus voltage are unknown until the final solution is obtained. Voltage controlled buses: Also known as generator buses or regulated buses or P- buses. At these buses, the real power and voltage magnitude are specified. The phase angles of the voltages and the reactive power are unknown until the final solution is obtained. The limits on the value of reactive power are also specified. The following table summarizes the above discussion: 1.2 BUS Admittance Matrix In order to obtain the bus-voltage equations, consider the sample 4-bus power system as shown in Fig. 1.1 1.1 The impedance diagram of sample 4-bus power system For simplicity resistances of the lines are neglected and the impedances shown in Fig.1.1 are expressed in per-unit on a common MVA base. Now impedances are converted to admittance, i.e, = 1.1 Fig.1.2 shows the admittance diagram and transformation to current sources and injects currents at buses 1 and 2 respectively. Node 0 (normally ground) is taken as reference. 1.2 the admittance diagram of 1.1 Applying KCL to the independent nodes 1,2,3,4 we have Rearranging the above equations, we get Let, The node equations reduce to Note that ,in Fig.1.2, there is no connection between bus 1 and bus 4, so Above equations can be written in matrix form, 1.2 or in general 1.3 Where vevtor of the injected currents (the current is positive when flowing into the bus and negative when flowing out of the bus) admittance matrix. Diagonal element of Y matrix is known as self-admittance or driving point admittance, i.e. 1.4 Off-diagonal element of y matrix is known as transfer admittance or mutual admittance, i.e. 1.5 can be obtained from equation (1.3), i.e. 1.6 From Fig.1.2, elements of Y matrix can be written as: So 1.3 BUS Loading Equations Consider i-th bus of a power system as shown in Fig.7.4. transmission lines are represented by their equivalent à Ã¢â€š ¬ models. is the total charging admittance at bus i. Fig 1.4: i-th bus of a power system Net injected current into the bus I can be written as : 1.7 Let us define 1.8 Or 1.9 The real and reactive power injected at bus is is 1.10 From equations 7.9 and 7.10 we get 1.11 1.12 1.4 BUS Impedance Matrix The bus impedance matrix for en t 1T nodes can be written as Unlike the bus admittance matrix, the bus impedance matrix cannot be formed by simple examination of the network circuit. The bus impedance matrix can be formed by the following methods: à ¢- Inversion of the admittance matrix à ¢- By open circuit testing à ¢- By step-by-step formation à ¢- From graph theory Direct inversion of the Y matrix is rarely implemented in computer applications. Certain assumptions in forming the bus impedance matrix are: 1. The passive network can be shown within a closed perimeter, (Fig.1.3). It includes the impedances of all the circuit components, transmission lines, loads, transformers, cables, and generators. The nodes of interest are brought out of the bounded network, and it is excited by a unit generated voltage Fig.1.3 Representation of a network as passive elements with loads and faults excluded. The nodes of interest are pulled out of the network and unit voltage is applied at the common node. 2. The network is passive in the sense that no circulating currents flow in the network. Also, the load currents are negligible with respect to the fault currents. For any currents to flow an external path (a fault or load) must exist. 3. All terminals marked 0 are at the same potential. All generators have the same voltage magnitude and phase angle and are replaced by one equivalent generator connected between 0 and a node. For fault current calculations a unit voltage is assumed 1.5 POWER IN AC CIRCUITS The concepts of instantaneous power, average power, apparent power, and reactive power are fundamental and are briefly discussed here. Consider lumped impedance Z, excited by a sinusoidal voltage E (1.13) (1.14) The first term is the average time-dependent power, when the voltage and current waveforms consist only of fundamental components. The second term is the magnitude of power swing. Equation (1.2) can be written as (1.15) The first term is the power actually exhausted in the circuit and the second term is power exchanged between the source and circuit, but not exhausted in the circuit. The active power is measured in watts and is defined as (1.16) The reactive power is measured in var and is defined as: (1.17) These relationships are shown in Fig. 1.4; cosÃŽÂ ¸ is called the power factor (PF) of the circuit, and ÃŽÂ ¸ is the power factor angle. The apparent power in VA is given by (1.18) The power factor angle is generally defined as (1.19) If cosÃŽÂ ¸=1, Q=0. Such a load is a unity power factor load. Except for a small percentage of loads, i.e., resistance heating and incandescent lighting, the industrial, commercial, or residential loads operate at lagging power factor. As the electrical equipment is rated on a kVA basis, a lower power factor derates the equipment and limits its capacity to supply active power loads. The reactive power flow and control is one important aspect of power flow. The importance of power factor (reactive power) control can be broadly stated as: à ¢- Improvement in the active power handling capability of transmission lines. à ¢- Improvement in voltage stability limits. à ¢- Increasing capability of existing systems: the improvement in power factor for release of a certain per unit kVA capacity can be calculated from Eq. (10.6): where PFimp is improved power factor, PFext is existing power factor, and kVAava is kVA made available as per unit of existing kVA. à ¢- Reduction in losses: the active power losses are reduced as these are proportional to the square of the current. With PF improvement, the current per unit for the same active power delivery is reduced. The loss reduction is given by the expression: Where Lossred is reduction in losses in per unit with improvement in power factor from PFext to PFimp. An improvement of power factor from 0.7 to 0.9 reduces the losses by 39.5% à ¢- . Improvement of transmission line regulation: the power factor improvement improves the line regulation by reducing the voltage drops on load flow. All these concepts may not be immediately clear and are further developed. Fig 1.4 1.5.1 Complex Power If the voltage vector is expressed as A t jB and the current vector as C t jD, then by convention the volt-ampe`res in ac circuits are vectorially expressed as E= (A +jB) (C- jD) = AC +BD +j(BC-AD) = P+ jQ (1.20) where P = AC t BD is the active power and Q BC _ AD is the reactive power; I_ is the conjugate of I. This convention makes the imaginary part representing reactive power negative for the leading current and positive for the lagging current. This is the convention used by power system engineers. If a conjugate of voltage, instead of current, is used, the reactive power of the leading current becomes positive. The power factor is given by cosÃŽÂ ¸= (1.21) 1.5.2 Conservation of Energy The conservation of energy concept (Tellegens theorem) is based on Kirchoff laws and states that the power generated by the network is equal to the power consumed by the network (inclusive of load demand and losses). If i1; i2; i3; . . . ; in are the currents and v1; v2; v3; . . . ; vn the voltages of n single-port elements connected in any manner: (1.22) This is an obvious conclusion. Also, in a linear system of passive elements, the complex power, active power, and reactive power should summate to zero: (1.23) (1.24) (1.25) 1.6 POWER FLOW IN A NODAL BRANCH The modeling of transmission lines is unique in the sense that capacitance plays a significant role and cannot be ignored, except for short lines of length less than approximately 50 miles (80 km). Let us consider power flow over a short transmission line. As there are no shunt elements, the line can be modeled by its series resistance and reactance, load, and terminal conditions. Such a system may be called a nodal branch in load flow or a two-port network. The sum of the sending end and receiving end active and reactive powers in a nodal branch is not zero, due to losses in the series admittance Ysr (Fig. 1.5). Let us define Ysr, the admittance of the series elements= j or Z= zl= l(+j)= + =1/Ysr, where l is the length of the line. The sending end power is = Where is conjugate.This gives where sending end voltage is Vs and, at the receiving end: If is neglected: where ÃŽÂ ´ in the difference between the sending end and receiving end voltage vector angles= (. For small values of delta, the reactive power equation can be written as Fig1.5 Power flow over a two-port line. where is the voltage drop. For a short line it is Therefore, the transfer of real power depends on the angle ÃŽÂ ´, called the transmission angle, and the relative magnitudes of the sending and receiving end voltages. As these voltages will be maintained close to the rated voltages, it is mainly a function of ÃŽÂ ´. The maximum power transfer occurs at ÃŽÂ ´=90(steady-state stability limit). The reactive power flows is in the direction of lower voltage and it is independent of ÃŽÂ ´. The following conclusions can be drawn: 1. For small resistance of the line, the real power flow is proportional to sin ÃŽÂ ´. It is a maximum at ÃŽÂ ´=90ËÅ ¡. For stability considerations the value is restricted to below ÃŽÂ ´=90ËÅ ¡. The real power transfer rises with the rise in the transmission voltage. 2. The reactive power flow is proportional to the voltage drop in the line, and is independent of ÃŽÂ ´. The receiving end voltage falls with increase in reactive power demand. 2.1 Practical Load Flow The requirements for load flow calculations vary over a wide area, from small industrial systems to large automated systems for planning, security, reactive power compensation, control, and on-line management. The essential requirements are: à ¢- High speed, especially important for large systems à ¢- Convergence characteristics, which are of major consideration for large systems, and the capability to handle ill-conditioned systems. à ¢- Ease of modifications and simplicity. i.e. adding, deleting, and changing system components, generator outputs, loads, and bus types. à ¢- Storage requirement, which becomes of consideration for large systems The size of the program in terms of number of buses and lines is important. Practically, all programs will have data reading and editing libraries, capabilities of manipulating system variables, adding or deleting system components, generation, capacitors, or slack buses. Programs have integrated databases, i.e., the impedance data for short-circuit or load flow calculations need not be entered twice, and graphic user interfaces. Which type of algorithm will give the speediest results and converge easily is difficult to predict precisely. Table.2.1 shows a comparison of earlier Z and Y matrix methods. Most programs will incorporate more than one solution method. While the Gauss-Seidel method with acceleration is still an option for smaller systems, for large systems some form of the NR decoupled method and fast load-flow algorithm are commonly used, especially for optimal power flow studies. Speed can be accelerated by optimal ordering .In fast decoupled load flow the convergence is geometric, and less than five iterations are required for practical accuraci es. If differentials are calculated efficiently the speed of the fast decoupled method can be even five times that of the NR method. Fast decoupled load flow is employed in optimization studies and in contingency evaluation for system security. The preparations of data, load types, extent of system to be modeled and specific problems to be studied are identified as a first step. The data entry can be divided into four main categories: bus data, branch data, transformers and phase shifters, and generation and load data. Shunt admittances, i.e., switched capacitors and reactors in required steps, are represented as fixed admittances. Apart from voltages on the buses, the study will give branch power flows; identify transformer taps, phase-shifter angles, loading of generators and capacitors, power flow from swing buses, load demand, power factors, system losses, and overloaded system components. No. Compared parameter Y matrix Z matrix Remarks 1 Digital computer memory requirements Small Large Sparse matrix techniques easily applied to Y matrix 2 Preliminary calculations Small Large Software programs can basically operate from the same data input 3 Convergence characteristics Slow, may not converge at all Strong Both methods may slow down on large systems 4 System modifications Easy Slightly difficult See text 2.2 Y-Matrix Method The Y-matrix iterative methods were the very first to be applied to load flow calculations on the early generation of digital computers. This required minimum storage, however, may not converge on some load flow problems. This deficiency in Y-matrix methods led to Z-matrix methods, which had a better convergence, but required more storage and slowed down on large systems. Some buses may be designated as PQ buses while the others are designated as PV buses. At a PV bus the generator active power output is known and the voltage regulator controls the voltage to a specified value by varying the reactive power output from the generator. There is an upper and lower bound on the generator reactive power output depending on its rating, and for the specified bus voltage, these bounds should not be violated. If the calculated reactive power exceeds generator Qmax, then Qmax is set equal to Q. If the calculated reactive power is lower than the generator Qmin, then Q is set equal to Qmin. At a PQ bus, neither the current, nor the voltage is known, except that the load demand is known. A mixed bus may have generation and also directly connected loads. The characteristics of these three types of buses are shown in Table 2-1. Bus type Known variable Unknown variable PQ Active and reactive power Current and voltage PV Active power and voltage Current and reactive power Swing Voltage Current, active and reactive power 2.2.1 GAUSS AND GAUSS-SEIDEL Y-MATRIX METHODS The principal of Jacobi iteration is shown in Fig. 2.1. The program starts by setting initial values of voltages, generally equal to the voltage at the swing bus. In a well-designed power system, voltages are close to rated values and in the absence of a better estimate all the voltages can be set equal to 1 per unit. From node power constraint, the currents are known and substituting back into the Y-matrix equations, a better estimate of voltages is obtained. These new values of voltages are used to find new values of currents. The iteration is continued until the required tolerance on power flows is obtained. This is diagrammatically illustrated in Fig. 2.1. Starting from an initial estimate of, the final value of x* is obtained through a number of iterations. The basic flow chart of the iteration process is shown in Fig. 2.2 Fig2.1 Illustration of numerical iterative process for final value of a function Fig. 2.2 Flow chart of basic iterative process of Jacobi-type iterations 2.2.2 Gauss Iterative Technique Consider that n linear equations in n unknowns () are given. The a coefficients and b dependent variables are known: à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦. These equations can be written as à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦. (2.1) An initial value for each of the independent variables is assumed. Let these values be denoted by The initial values are estimated as à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦. These are substituted into Eq. (2.1), giving à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦. These new values of are substituted into the next iteration. In general, at the k-th iteration: à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦. 2.2.3 Gauss-Seidel Y-Matrix Method In load flow calculations the system equations can be written in terms of current, voltage, or power at the k-th node. We know that the matrix equation in terms of unknown voltages, using the bus admittance matrix for n+ 1 node, is Although the currents entering the nodes from generators and loads are not known, these can be written in terms of P, Q, and V: The convention of the current and power flow is important. Currents entering the nodes are considered positive, and thus the power into the node is also positive. A load draws power out of the node and thus the active power and inductive vars are entered as:-p j (-Q) =-p + j Q. The current is then (-P + j Q)/. The nodal equal of current at the k-th node becomes: In general, for the k-th node: (2.2) The k-th bus voltage at r + 1 iteration can be written as (2.3) The voltage at the k-th node has been written in terms of itself and the other voltages. The first equation involving the swing bus is omitted, as the voltage at the swing bus is already specified in magnitude and phase angle. The Gauss-Seidel procedure can be summarized for PQ buses in the following steps: 1: Initial phasor values of load voltages are assumed, the swing bus voltage is known, and the controlled bus voltage at generator buses can be specified. Though an initial estimate of the phasor angles of the voltages will accelerate the final solution, it is not necessary and the iterations can be started with zero degree phase angles or the same phase angle as the swing bus. A flat voltage start assumes 1 + j0 voltages at all buses, except the voltage at the swing bus, which is fixed. 2: Based on the initial voltages, the voltage at a bus in the first iteration is calculated using Eq. (2.2) 3: The estimate of the voltage at bus 2 is refined by repeatedly finding new values of by substituting the value of into the right-hand side of the equation. 4: The voltages at bus 3 are calculated using the latest value of found in step 3 and similarly for other buses in the system. This completes one iteration. The iteration process is repeated for the entire network till the specified convergence is obtained. A generator bus is treated differently; the voltage to be controlled at the bus is specified and the generator voltage regulator varies the reactive power output of the generator within its reactive power capability limits to regulate the bus voltage: where stands for the imaginary part of the equation. The revised value of is found by substituting the most updated value of voltages: For a PV bus the upper and lower limits of var generation to hold the bus voltage constant are also given. The calculated reactive power is checked for the specified limits: If the calculated reactive power falls within the specified limits, the new value of voltage is calculated using the specified voltage magnitude and. This new value of voltage is made equal to the specified voltage to calculate the new phase angle. If the calculated reactive power is outside the specified limits, then, This means that the specified limits are not exceeded and beyond the reactive power bounds, the PV bus is treated like a PQ bus. A flow chart is shown in Fig. 2.3 2.3 Newton-Rapson Method Newton-Raphson method is an iterative method which approximates the set of non-linear simultaneous equations to a set of linear equations using Taylors series expansion and the terms are restricted to first order approximation. 2.3.1 Simultaneous Equations The Taylor series is applied to n nonlinear equations in n unknowns, à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦. As a first approximation, the unknowns represented by the initial values can be substituted into the above equations, where are the first estimates of n unknowns. On transposing Where is abbreviated as The original nonlinear equations have been reduced to linear equations in The subsequent approximations are à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦ Or in matrix form: The matrix of partial derivatives is called a Jacobian matrix. This result is written as This means that determination of unknowns requires inversion of the Jacobian 2.3.2 Rectangular Form of Newton-Rapson Method of Load Flow The power flow equation at a PQ node is Voltage can be written as: Thus, the power is ] ] Equating the real and imaginary parts, the active and reactive power at a PQ node is: where and are functions of and . Starting from the initial values, new values are found which differ from the initial values by and (First iteration) (First iteration) For a PV node (generator bus) voltage and power are specified. The reactive power equation is replaced by a voltage equation: 2.3.3 Polar Form of Jacobian Matrix The voltage equation can be written in polar form: Thus the power is Equating real and imaginary terms: The Jacobian in polar form for the same four-bus system is The slack bus has no equation, because the active and reactive power at this bus is unspecified and the voltage is specified. At PV bus 4, the reactive power is unspecified and there is no corresponding equation for this bus in terms of the variable. The partial derivatives can be calculated as follows: 2.3.4 Calculation Procedure of Newton-Raphson Method The procedure is summarized in the following steps, and flow charts are shown in Figs 2.4 and 2.5 à ¢- Bus admittance matrix is formed. à ¢- Initial values of voltages and phase angles are assumed for the load (PQ) buses. Phase angles are assumed for PV buses. Normally, the bus voltages are set equal to the slack bus voltage, and phase angles are assumed equal to 0ËÅ ¡, i.e., a flat start. à ¢- Active and reactive powers, P and Q, are calculated for each load bus à ¢- P and Q can, therefore, be calculated on the basis of the given power at the buses à ¢- For PV buses, the exact reactive power are not specified, but its limits are known. If the calculated value of the reactive power is within limits, only P is calculated. If the calculated value of reactive power is beyond the specified limits, then an appropriate limit is imposed and Q is also calculated by subtracting the calculated value of the reactive power from the maximum specified limit. The bus under consideration is now treated as a PQ (load) bus. à ¢- The elements of the Jacobian matrix are calculated à ¢- This gives and à ¢- Using the new values ofand, the new values of voltages and phase angles are calculated. à ¢- The next iteration is started with these new values of voltage magnitudes and phase angles. à ¢- The procedure is continued until the required tolerance is achieved. This is generally 0.1kW and 0.1 kvar. Fig 2.4 Flow chart for NR method of load flow for PQ buses. Fig.2.5Flow chart for NR method of load flow for PV buses 2.3.5 Impact Loads and Motor Starting Load flow presents a frozen picture of the distribution system at a given instant, depending on the load demand. While no idea of the transients in the system for a sudden change in load application or rejection or loss of a generator or tie-line can be obtained, a steady-state picture is presented for the specified loading conditions. Each of these transient events can be simulated as the initial starting condition, and the load flow study rerun as for the steady-state case. Suppose a generator is suddenly tripped. Assuming that the system is stable after this occurrence, we can calculate the redistribution of loads and bus voltages by running the load flow calculations afresh, with generator 4 omitted. Similarly, the effect of an outage of a tie-line, transformer, or other system component can be studied. Table 2-2 Representation of Load Models in Load Flow 3. Conclusion Load flow is a solution of the steady-state operating conditions of a power system. It presents a frozen picture of a scenario with a given set of conditions and constraints. This can be a limitation, as the power systems operations are dynamic. In an industrial distribution system the load demand for a specific process can be predicted fairly accurately and a few load flow calculations will adequately describe the system. For bulk power supply, the load demand from hour to hour is uncertain, and winter and summer load flow situations, though typical, are not adequate. A moving picture scenario could be created from static snapshots, but it is rarely adequate in large systems having thousands of controls and constraints. Thus, the spectrum of load flow (power flow) embraces a large area of calculations, from calculating the voltage profiles and power flows in small systems to problems of on-line energy management and optimization strategies in interconnected large power systems. By the load flow studies which performed using digital computer simulations. I have a main idea of how a power networks power flow calculation operation, planning, running, and development of control strategies. Applied to large systems for optimization, security, and stability, the algorithms become complex and involved. While the study I have done above just a small part of the research and I think the treatment of load flow, and finally optimal power flow, will unfold in my following study.

Essay on Blanche DuBois in Tennessee Williams A Streetcar Named Desi

The Destruction of Blanche in A Streetcar Named Desire  Ã‚     Ã‚   A Streetcar Named Desire is an intricate web of complex themes and conflicted characters. Set in the pivotal years immediately following World War II, Tennessee Williams infuses Blanche and Stanley with the symbols of opposing class and differing attitudes towards sex and love, then steps back as the power struggle between them ensues. Yet there are no clear cut lines of good vs. evil, no character is neither completely good nor bad, because the main characters, (especially Blanche), are so torn by conflicting and contradictory desires and needs. As such, the play has no clear victor, everyone loses something, and this fact is what gives the play its tragic cast. In a larger sense, Blanche and Stanley, individual characters as well as symbols for opposing classes, historical periods, and ways of life, struggle and find a new balance of power, not because of ideological rights and wrongs, but as a matter of historical inevitability. Interestingly, Williams finalizes the resol ution of this struggle on the most base level possible. In Scene Ten, Stanley subdues Blanche, and all that she stands for, in the same way men have been subduing women for centuries. Yet, though shocking, this is not out of keeping with the themes of the play for, in all matters of power, force is its ultimate manifestation. And Blanche is not completely unwilling, she has her own desires that draw her to Stanley, like a moth to the light, a light she avoids, even hates, yet yearns for. A first reader of Scene Ten of the play might conclude that sex between Stanley and Blanche seems out of place. It might not ring true given the preceding circumstances. There is not much overt sexual tensi... ...al mechanism, and desire only a function of reproduction. Yet, it is not so. Individual human destiny is much stronger than the force of history if only individuals grapple with who they are and the forces pressuring them, and have the courage to meet the mass wave head on. Perhaps no one in this play does so, but the desire is there and we can learn from their failure. Works Cited Bloom, Herald (ed.).   Tennessee Williams.   New York: Chelsea House, 1987. Donahue, Francis.   The Dramatic World of Tennessee Williams.   New York: Frederic Ungar Publishing Co., 1964. Hirsch, Foster.   A Portrait of the Artist-The Plays of Tennessee Williams.   London: Kennikat Press, 1979. Londre, F.H.   Tennessee Williams.   New York: Frederic Ungar Publishing Co., 1979. Williams, Tennessee.   A Streetcar Named Desire.   Stuttgart: Phillip Reclam, 1988.         

Сauses of the Protestant Reformation

The term â€Å"Protestant Reformation† is used to describe what was originally an effort to â€Å"reform† Western or Catholic Christianity (the term Catholic means â€Å"universal†) but ended up creating a separate tradition. Several stages can be identified as part of the Reformation, beginning with Martin Luther (1483-1546) in Germany then shifting to John Calvin (1509-1564) and Huldrrych Zwingli (1481-1531) in Switzerland (206). Reforming ideas later spread to England, leading to the Church of England (Anglican) breaking from Rome (1533) and the growth of many Protestant denominations, such as Methodist, Baptist and Congregational.Luther’s nailing of his 95 theses to the door of the Castle Church in Wittenburg in 1517 is widely considered as launching the Reformation but earlier people, ideas and movements contributed toward Luther’s actions. Political and religious factors both lie behind the Reformation. First, religious then political causes o f the Reformation are discussed below. Among several â€Å"forerunners† of the reformation was John Wycliffe (d. 1384), the English Bible translator and his disciple Jan Huss (1372-1415) of Bohemia. Earlier movements and attempts to reform the Church also lie behind the Reformation.Many wanted ordinary Christians to read the Bible for themselves and blurred the distinction between lay and ordained. One of the major emphases of the reformation was the â€Å"priesthood of all believers. † Direct access to the bible in vernacular languages, not in Latin which few lay people spoke or read, was regarded by Catholic priests as dangerous, by-passing their priestly role as mediators. Luther, an Augustinian monk and professor at Wittenburg, became convinced that the Church substituted itself for â€Å"faith†, acting as if â€Å"salvation† was a commodity that could be bought and sold, which the Pope did in the form of indulgences.Preoccupied with â€Å"justificat ion,† Luther determined that faith is God’s free gift; it cannot be earned by good works or bought from the church. He also criticized the wealth and political power of the Church. He renounced celibacy, arguing that the Christian life is a vocation that should be lived out in the world. Protestants rejected papal authority; gave priority to the bible, recognized two (as compared with seven) sacraments, baptism and communion (some jettisoned the concept of â€Å"sacrament†); gave communion in both kinds (as compared with only bread) and taught the priesthood of all believers.Behind these Protestant emphases was discontentment with a Church that was dominated by priests, practiced many traditions that could not be traced back to scripture and that was preoccupied with wealth and power at the expense of spirituality. Such practices as buying church offices (simony), clerical marriage or the keeping of mistresses as well as the sale of indulgences, all compromised t he Church’s moral and spiritual authority. Faith for Protestants usually involves a personal experience of renewal. You are not born a Christian but become Membership of a Church does not mean that you are necessarily a true believer.Invention of the printing press, too, made placing the Bible at the center possible because more and more people could now read the bible. Translation also facilitated this process. The above also had political implications. Much money went from countries such as the German states to Italy to pay for building churches or to maintain the lavish lifestyle of popes and bishops in Rome. Earlier, during what was called the investiture controversy of the 11th and 12th centuries, the Pope had vied with kings and princes over who had the right to appoint church officers, with the Pope claiming that only he had the right to do so.In fact, there was also historical tension between the Pope’s claim to be the ultimate temporal as well as spiritual aut hority and kings who saw themselves as ruling directly under divine authority with no need for papal approval. Following Luther’s denunciation of indulgences and of other beliefs and practices, several German princes supported his new movement, asserting that they had the right to choose which version of Christianity would be the â€Å"church† within their state.Effectively, this was what Henry VIII did when he declared that the Church of England was independent from Rome, that it was the established church of his realm. Henry became head of the Church of England. In theory, the Popes saw the Church as â€Å"above† the state, since they legitimized kingly succession. In Protestantism, the Church tends to be regarded as â€Å"under† the state, or as a partner in running the state. Luther and other reformers were in part successful because they had the support of political leaders.From the perspective of kings and other temporal rulers, weakening the power of the Pope and retaining money within their own states was a significant factor. For Luther and his fellow reformers, the Reformation had more to do with matters of the heart. Luther experienced a personal transformation while preparing his lectures on the Book of Romans and it was this experience that prompted his ideas about â€Å"faith alone†, â€Å"grace alone† and â€Å"scripture alone†. Yet without the support of temporal rulers he would probably have been convicted of heresy and executed.Rather than single out one or several causes of the Reformation as the most important, arguably, what lies at the root of the Reformation was a new spirit of humanism that was sweeping Europe. Luther was no â€Å"humanist† but he did want to give Christianity back to the people and in a sense to individuals, who would study the Bible, undergo personal, individual religious experiences and who would not have to answer to an external sources of authority. No one wou ld stand between a person and their God, although kings tried to do so as stamped out alternatives to their choice of a state church. . The Renaissance has been called the `birth of modernity. `Why? The â€Å"Renaissance† describes the period from about 1300 to about 1600, although historians disagree about the exact parameters. Historians actually identify several â€Å"renaissances† such as the English renaissance and the Scottish renaissance although the term is often restricted to the Italian renaissance. â€Å"Modernity† can be a misleading concept, because what was thought â€Å"modern† in the 1920’s seems old-fashioned in the opening years of the 21st century. The word means â€Å"re-birth†.Following the Black Death, which emasculated the population of Europe killing about a quarter of the population, some people decided that if life was short they ought to become as much as possible masters and mistresses of their destiny. Life was t oo fragile to be subject to a great many limitations and controls. The typical Renaissance Man did not confine himself to a single area of interest but studied a wide range of disciplines. Leonardo Da Vinci (1452-1519) for example was a scientist, an inventor, an artist, a anatomist, musician, visionary, musician and engineer.Arguably, Da Vinci did not want to miss out on any aspect of learning that was accessible to him as a human individual. He wanted everything that life could afford him. One contributing factor behind the emergence of the Renaissance was the rediscovery of classical learning aided by the influx of Greek refugees from Constantinople after 1453, when it fell to the Ottomans. Scholars from the East brought with them copies of Aristotle, Plato and other Greek masters. Other forgotten texts traveled to Europe via the Muslim world through Spain. The City-state of Florence was instrumental in developing Renaissance ideas.Some suggest that after the Black Death merchant s and workers gained importance. Since they were fewer in number, they could demand higher wages and more privileges. In smaller states, their importance was magnified. More wealth led to more interest in spending their leisure time pursuing learning and other interesting activities. Previously, scholarship had been dominated and policed by the Church to ensure that ideas though dangerous and contrary to Christian teaching did not develop. Lay people now turned to serious academic endeavors and were less concerned with conformity to Christian ideas.What many saw in the classical texts was confidence in humanity itself, in human ability to shape the world, to control human destiny. The way in which the human form was depicted in Greek sculpture testified to the nobility of the human form. Renaissance men such as Petrach (1304-1374) actually thought that ancient times were superior and wanted to reconstruct the past. Ancient knowledge of the functioning of the human body suggested the uniqueness of â€Å"man† among other creatures. All of this shifted the human to the center. Renaissance thought is not characteristically atheist but it is generally classed as â€Å"humanist†.Much scholarship focused on the humanities, that is, poetry, grammar, history, moral philosophy and rhetoric and there was a deep concern with how men and women could live virtuous lives. Giovanni Pico della Mirandola (1463-1494) famously said that â€Å"man is the measure of all things† which can be taken as the motto of the age. The Renaissance was also given a boost because wealthy people decided that patronizing art and learning was worthwhile. In what sense did the Renaissance prefigure or give birth to modernity? Modernity here is understood as the age of mature humanism. God is no longer thought to supervise and pre-ordain human affairs.The Church is no longer the guardian of learning. Knowledge is that which can be empirically proven, regardless of whether the Ch urch approves or not. While many â€Å"great men† of the Renaissance still believed in God and in eternal punishment or reward, others began to distance themselves from religion. Some tended to think that God created the world and humanity but then stepped aside, leaving people to determine their own destiny. Modern thinkers do not look to religious doctrines to determine â€Å"right† from â€Å"wrong† but see notions of morality as socially agreed constructs which are therefore fluid and subject to change.A thinker such as John Stuart Mill (1806-73) argued that a world free of religion would be more moral because people would act not in order to earn a reward but simply because an act was moral. Spinoza (1632-77) produced a system of ethics that was derived from rational thought, not from scripture. The idea that humans, by ingenuity can cure diseases, shape the world to suit their needs, redeem past mistakes by new feats of engineering and skill, puts â€Å"h umanity† at the center and all but makes God redundant.God becomes either wishful thinking or a dangerous idea, one that prevents people from taking responsibility. Historians, though, are divided on whether the Renaissance was a bridge from the Middle Ages to modernity or whether nostalgia for the past was so rampant that it could not prepare for an unknown the future. Or, even if Renaissance people did glorify the past this was in order to improve the world in which they lived and the world in which their children and their children would later live. Renaissance people were confident that human skill could make the world a better, more attractive place.The impetus to know the world led to the great explorers, which in turn inspired the more recent quest to reach the stars. Arguably, Renaissance people looked back to take what was best from the past so that humanity could move forward. Thus, modernity has its roots in Renaissance conviction that man is the measure of all thin gs. 2. The Early Middle Ages are often referred to as the `Dark Ages. ` Why? Was there any learning during this period? Dividing history into periods and naming them is problematic because not everyone agrees on how time should be divided.Characterizing an era by its main ideas or ethos, such as â€Å"Renaissance†, â€Å"Enlightenment† may be better than using such terms as â€Å"Middle Ages† or â€Å"Modern† because what can now be called â€Å"Middle† will later be nearer the start of written history. What is now â€Å"modern† will seem antiquated. The term â€Å"Middle Ages† may remain appropriate when applied to the period between the classical and the Renaissance, that is, from the 5th to the 13th centuries, although the Renaissance is sometimes included in the late Middle Ages, ending in the 15th century.Defining historical periods by describing their ethos depends on establishing a consensus about what characterized them. It wa s the Renaissance thinker, Petrarch (d. 1374) who first referred to the early Middle Ages (roughly end of fifth to end of ninth century) as the Dark Ages. Petrarch believed that the classical world was superior to the age in which he lived, itself characterized as a period of â€Å"re-birth†, that is, of reviving ancient ideas. Consequently, for Petrach, the period between the end of the classical age and the beginning of the Renaissance was â€Å"dark†.The term ‘Middle Ages† was also coined by a Renaissance period scholar, Flavio Biondo (d. 1463) who distinguished the classical, the Middle and the modern periods. For him, modernity began around about his own time, or perhaps from the Fall of Constantinople (1453). During the Dark Ages, Learning was rare, confined almost exclusively to the Church and many clergy were badly educated. Europe was divided, since the attempt to unite the former provinces of the Roman Empire as the Holy Roman Empire failed.The Ca tholic Church was the only pan-European organization and this may have hindered the development of science because little other than theology was taught or studied. There was hardly any serious historiography and literature, all in Latin, was almost exclusively hagiography or related to theology. Poetry, creative and imaginative writing, fiction, was conspicuous by their absence. Art did exist but was controlled by the Church and comparatively few great buildings or cultural artifacts were produced, although some were. Examples of great art are the illuminated mss of the Bible, such as the Book of Kells.Certainly, there was a great deal of superstition during the Dark Ages and anything that the Church authorities could not understand was condemned. This included some ancient knowledge of medicine, dubbed â€Å"witchcraft† and spiritual practices that challenges the Church’s authority, such as Celtic Christianity in Ireland, Scotland and Wales where women played a great er role and nature was reverenced. In fact, however, there were centers of learning where non-religious subjects were explored: some monasteries were isolated but maintained libraries where away from the prying age of the protectors of orthodoxy forbidden ideas were explored.The term â€Å"dark ages† highlights the contrast between the age of discovery when development took place in many areas, in science, medicine and technology from the Renaissance on and the earlier lack of progress or achievement. Yet others argue that some important aspects of modern life have their roots in the Dark Ages. For example, although the experiment of unifying Europe under the Holy Roman Empire failed, the Catholic Church did represent a unifying ideal. People were conscious of belonging to an entity that was larger than their political unit. People saw themselves as belonging to the same race, with the same rights.The idea of the whole globe as a common habitat may stem from this early unders tanding of human unity. The idea that everyone, even rulers were subject to the same law and the use of juries of peers can be traced back to the Dark Ages. The jury system remains fundamental to how justice operates in the modern world. In Art, realism was a feature during the Dark Ages, laying foundations for later developments such as the Romanesque and Gothic styles. Universities emerged just after the end of the Dark Ages and cannot have appeared from nowhere, that is, the idea of the University must have some roots in the so-called Dark Ages.The oldest Universities in Europe such as Bologna, Paris and Oxford taught the arts, law, medicine as well as theology. Enough people versed in these subjects but who were not themselves graduates of universities must have existed to teach relevant courses. Presumably, they were the products of monastic centers of learning that had pushed the boundaries of knowledge beyond theological topics. Thus, the term â€Å"Dark Ages† may refl ect the perspective of Renaissance scholars more accurately than it does those of modern scholars.On the one hand, the Renaissance is depicted as the beginning of modernity or as its precursor, suggesting that modernity built on antecedents and did not materialize spontaneously, appearing ex nihilo. Similarly, some ideas from the Dark Ages such as early contact with Muslim learning in Spain, may have laid foundations on which the Renaissance built. Pre-Renaissance Europeans were not completely ignorant about classical thinkers, for example. There may be better ways of dividing and characterizing history, although both terms â€Å"Dark Ages† and â€Å"Middle Ages† have had a long shelf life.

Deception Point Page 103

Unfortunately, Delta-One had seen the complexity of the control panel near the trapdoor-a series of unmarked levers and dials that apparently controlled the trapdoor, the winch motor, and numerous other commands. He had no intention of hitting the wrong lever and risking his partner's life by mistakenly dropping the sub into the sea. Eliminate all risk. Never rush. He would force Tolland to perform the actual release. And to ensure he did not try anything tricky, Delta-One would take out insurance known in his business as â€Å"biological collateral.† Use your adversaries against one another. Delta-One swung the gun barrel directly into Rachel's face, stopping only inches from her forehead. Rachel closed her eyes, and Delta-One could see Tolland's fists clench in a protective anger. â€Å"Ms. Sexton, stand up,† Delta-One said. She did. With the gun firmly on her back, Delta-One marched her over to an aluminum set of portable stairs that led up to the top of the Triton sub from behind. â€Å"Climb up and stand on top of the sub.† Rachel looked frightened and confused. â€Å"Just do it,† Delta-One said. Rachel felt like she was moving through a nightmare as she climbed up the aluminum gangway behind the Triton. She stopped at the top, having no desire to step out over the chasm onto the suspended Triton. â€Å"Get on top of the sub,† the soldier said, returning to Tolland and pushing the gun against his head. In front of Rachel the soldier who was in the clamps watched her, shifting in pain, obviously eager to get out. Rachel looked at Tolland, who now had a gun barrel to his head. Get on top of the sub. She had no choice. Feeling like she was edging out onto a precipice overhanging a canyon, Rachel stepped onto the Triton's engine casing, a small flat section behind the rounded dome window. The entire sub hung like a massive plumb bob over the open trapdoor. Even suspended on its winch cable, the nine-ton sub barely registered her arrival, swinging only a few millimeters as she steadied herself. â€Å"Okay, let's move,† the soldier said to Tolland. â€Å"Go to the controls and close the trapdoor.† At gunpoint, Tolland began moving toward the control panel with the soldier behind him. As Tolland came toward her, he was moving slowly, and Rachel could feel his eyes fixing hard on her as if trying to send her a message. He looked directly at her and then down at the open hatch on top of the Triton. Rachel glanced down. The hatch at her feet was open, the heavy circular covering propped open. She could see down into the one-seater cockpit. He wants me to get in? Sensing she must be mistaken, Rachel looked at Tolland again. He was almost to the control panel. Tolland's eyes locked on her. This time he was less subtle. His lips mouthed, â€Å"Jump in! Now!† Delta-One saw Rachel's motion out of the corner of his eye and wheeled on instinct, opening fire as Rachel fell through the sub's hatch just below the barrage of bullets. The open hatch covering rang out as the bullets ricocheted off the circular portal, sending up a shower of sparks, and slamming the lid closed on top of her. Tolland, the instant he'd felt the gun leave his back, made his move. He dove to his left, away from the trapdoor, hitting the deck and rolling just as the soldier spun back toward him, gun blazing. Bullets exploded behind Tolland as he scrambled for cover behind the ship's stern anchor spool-an enormous motorized cylinder around which was wound several thousand feet of steel cable connected to the ship's anchor. Tolland had a plan and would have to act fast. As the soldier dashed toward him, Tolland reached up and grabbed the anchor lock with both hands, yanking down. Instantly the anchor spool began feeding out lengths of cable, and the Goya lurched in the strong current. The sudden movement sent everything and everyone on the deck staggering sidelong. As the boat accelerated in reverse on the current, the anchor spool doled out cable faster and faster. Come on, baby, Tolland urged. The soldier regained his balance and came for Tolland. Waiting until the last possible moment, Tolland braced himself and rammed the lever back up, locking the anchor spool. The chain snapped taut, stopping the ship short and sending a tremulous shudder throughout the Goya. Everything on deck went flying. The soldier staggered to his knees near Tolland. Pickering fell back from the railing onto the deck. The Triton swung wildly on its cable. A grating howl of failing metal tore up from beneath the ship like an earthquake as the damaged strut finally gave way. The right stern corner of the Goya began collapsing under its own weight. The ship faltered, tilting on a diagonal like a massive table losing one of its four legs. The noise from beneath was deafening-a wail of twisting, grating metal and pounding surf. White-knuckled inside the Triton cockpit, Rachel held on as the nine-ton machine swayed over the trapdoor in the now steeply inclined deck. Through the base of the glass dome she could see the ocean raging below. As she looked up, her eyes scanning the deck for Tolland, she watched a bizarre drama on the deck unfold in a matter of seconds. Only a yard away, trapped in the Triton's claws, the clamped Delta soldier was howling in pain as he bobbed like a puppet on a stick. William Pickering scrambled across Rachel's field of vision and grabbed on to a cleat on the deck. Near the anchor lever, Tolland was also hanging on, trying not to slide over the edge into the water. When Rachel saw the soldier with the machine gun stabilizing himself nearby, she called out inside the sub. â€Å"Mike, look out!† But Delta-One ignored Tolland entirely. The soldier was looking back toward the idling helicopter with his mouth open in horror. Rachel turned, following his gaze. The Kiowa gunship, with its huge rotors still turning, had started to slowly slide forward down the tipping deck. Its long metal skids were acting like skis on a slope. It was then that Rachel realized the huge machine was skidding directly toward the Triton. Scrambling up the inclined deck toward the sliding aircraft, Delta-One clambered into the cockpit. He had no intention of letting their only means of escape slide off the deck. Delta-One seized the Kiowa's controls and heaved back on the stick. Lift off! With a deafening roar, the blades accelerated overhead, straining to lift the heavily armed gunship off the deck. Up, goddamn it! The chopper was sliding directly toward the Triton and Delta-Two suspended in its grasp. With its nose tipped forward, the Kiowa's blades were also tipped, and when the chopper lurched off the deck, it sailed more forward than up, accelerating toward the Triton like a giant buzz saw. Up! Delta-One pulled the stick, wishing he could drop the half ton of Hellfire warheads weighing him down. The blades just missed the top of Delta-Two's head and the top of the Triton sub, but the chopper was moving too fast. It would never clear the Triton's winch cable. As the Kiowa's 300-rpm steel blades collided with the sub's fifteen-ton capacity braided steel winch cable, the night erupted with the shriek of metal on metal. The sounds conjured images of epic battle. From the chopper's armored cockpit, Delta-One watched his rotors tear into the sub's cable like a giant lawn mower running over a steel chain. A blinding spray of sparks erupted overhead, and the Kiowa's blades exploded. Delta-One felt the chopper bottom out, its struts hitting the deck hard. He tried to control the aircraft, but he had no lift. The chopper bounded twice down the inclined deck, then slid, crashing into the ship's guardrail. For a moment, he thought the rail would hold. Then Delta-One heard the crack. The heavily laden chopper listed over the brink, plummeting into the sea. Inside the Triton, Rachel Sexton sat paralyzed, her body pressed back into the sub's seat. The minisub had been tossed violently as the chopper's rotor wrapped around the cable, but she had managed to hang on. Somehow the blades had missed the main body of the sub, but she knew there had to be major damage to the cable. All Rachel could think of at that point was escaping from the sub as fast as she could. The soldier trapped in the clamps stared in at her, delirious, bleeding, and burned from the shrapnel. Beyond him, Rachel saw William Pickering still holding on to a cleat on the slanting deck.