979 resultados para Pennsylvania. Giant power board.


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This paper investigates vertical economies between generation and distribution of electric power, and horizontal economies between different types of power generation in the U.S. electric utility industry. Our quadratic cost function model includes three generation output measures (hydro, nuclear and fossil fuels), which allows us to analyze the effect that generation mix has on vertical economies. Our results provide (sample mean) estimates of vertical economies of 8.1% and horizontal economies of 5.4%. An extensive sensitivity analysis is used to show how the scope measures vary across alternative model specifications and firm types. © 2012 Blackwell Publishing Ltd and the Editorial Board of The Journal of Industrial Economics.

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We investigate the role of CEO power and government monitoring on bank dividend policy for a sample of 109 European listed banks for the period 2005-2013. We employ three main proxies for CEO power: CEO ownership, CEO tenure, and unforced CEO turnover. We show that CEO power has a negative impact on dividend payout ratios and on performance, suggesting that entrenched CEOs do not have the incentive to increase payout ratios to discourage monitoring from minority shareholders. Stronger internal monitoring by board of directors, as proxied by larger ownership stakes of the board members, increases performance but decreases payout ratios. These findings are contrary to those from the entrenchment literature for non-financial firms. Government ownership and the presence of a government official on the board of directors of the bank, also reduces payout ratios, in line with the view that government is incentivized to favor the interest of bank creditors before the interest of minority shareholders. These results show that government regulators are mainly concerned about bank safety and this allows powerful CEOs to distribute low payouts at the expense of minority shareholders.

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This is a historical case study on school desegregation and power in Broward County, Florida from 1970 to 1998. The purpose of this study is to describe, explain and analyze types of power used by the School Board of Broward County, Florida and community activists, in their efforts to influence desegregation decisions from 1970 to 1998. In addition, this study explains who benefited and who won from the School Board's desegregation decisions and who governed those decisions? ^ A historical case study approach was used as the method for conducting this study. Data sources included 11 interviews of individuals who were involved in school desegregation issues as either School Board officials or community activists and 10 archival data sources. ^ The theoretical models of Russell, Galbraith, Wartenberg and Domhoff were used to determine the different types of power techniques used by School Board officials and community activists and to answer the questions: who benefited and who won from the School Board's desegregation decisions and who governed those policies and practices? ^ The primary beneficiaries of school desegregation policies and practices in Broward County were: white, affluent communities and the builders, developers, realtors and other businesses in the western suburban communities. All of the data sources indicated that the black community did not benefit from the School Board's desegregation policies. ^ The primary power techniques used by School Board officials to influence desegregation policies and practices was “power over opinions” and compensation. These power techniques were manifested by the School Board publicly disputing the allegations raised by community activists and by compensating those who supported and promoted the School Board's desegregation policies and practices. ^ The power techniques primarily used by community activists were coercive force and “power over opinions.” They effectively used these power techniques to change the School Board's policies and practices they felt were detrimental to black children and the black community. ^ Based on the analysis of the qualitative data, it can be concluded that black children did not benefit from school desegregation in Broward County, Florida and the community continues to suffer residual effects from past desegregation policies and practices. ^

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High efficiency of power converters placed between renewable energy sources and the utility grid is required to maximize the utilization of these sources. Power quality is another aspect that requires large passive elements (inductors, capacitors) to be placed between these sources and the grid. The main objective is to develop higher-level high frequency-based power converter system (HFPCS) that optimizes the use of hybrid renewable power injected into the power grid. The HFPCS provides high efficiency, reduced size of passive components, higher levels of power density realization, lower harmonic distortion, higher reliability, and lower cost. The dynamic modeling for each part in this system is developed, simulated and tested. The steady-state performance of the grid-connected hybrid power system with battery storage is analyzed. Various types of simulations were performed and a number of algorithms were developed and tested to verify the effectiveness of the power conversion topologies. A modified hysteresis-control strategy for the rectifier and the battery charging/discharging system was developed and implemented. A voltage oriented control (VOC) scheme was developed to control the energy injected into the grid. The developed HFPCS was compared experimentally with other currently available power converters. The developed HFPCS was employed inside a microgrid system infrastructure, connecting it to the power grid to verify its power transfer capabilities and grid connectivity. Grid connectivity tests verified these power transfer capabilities of the developed converter in addition to its ability of serving the load in a shared manner. In order to investigate the performance of the developed system, an experimental setup for the HF-based hybrid generation system was constructed. We designed a board containing a digital signal processor chip on which the developed control system was embedded. The board was fabricated and experimentally tested. The system's high precision requirements were verified. Each component of the system was built and tested separately, and then the whole system was connected and tested. The simulation and experimental results confirm the effectiveness of the developed converter system for grid-connected hybrid renewable energy systems as well as for hybrid electric vehicles and other industrial applications.

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This is a historical case study on school desegregation and power in Broward County, Florida from 1970 to 1998. The purpose of this study is to describe, explain and analyze types of power used by the School Board of Broward County, Florida and community activists, in their efforts to influence desegregation decisions from 1970 to 1998. In addition, this study explains who benefited and who won from the School Board's desegregation decisions and who governed those decisions? A historical case study approach was used as the method for conducting this study. Data sources included 11 interviews of individuals who were involved in school desegregation issues as either School Board officials or community activists and 10 archival data sources. The theoretical models of Russell, Galbraith, Wartenberg and Domhoff were used to determine the different types of power techniques used by School Board officials and community activists and to answer the questions: who benefited and who won from the School Board's desegregation decisions and who governed those policies and practices? The primary beneficiaries of school desegregation policies and practices in Broward County were: white, affluent communities and the builders, developers, realtors and other businesses in the western suburban communities. All of the data sources indicated that the black community did not benefit from the School Board's desegregation policies. The primary power techniques used by School Board officials to influence desegregation policies and practices was "power over opinions" and compensation. These power techniques were manifested by the School Board publicly disputing the allegations raised by community activists and by compensating those who supported and promoted the School Board's desegregation policies and practices. The power techniques primarily used by community activists were coercive force and "power over opinions." They effectively used these power techniques to change the School Board's policies and practices they felt were detrimental to black children and the black community. Based on the analysis of the qualitative data, it can be concluded that black children did not benefit from school desegregation in Broward County, Florida and the community continues to suffer residual effects from past desegregation policies and practices.

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Backscatter communication is an emerging wireless technology that recently has gained an increase in attention from both academic and industry circles. The key innovation of the technology is the ability of ultra-low power devices to utilize nearby existing radio signals to communicate. As there is no need to generate their own energetic radio signal, the devices can benefit from a simple design, are very inexpensive and are extremely energy efficient compared with traditional wireless communication. These benefits have made backscatter communication a desirable candidate for distributed wireless sensor network applications with energy constraints.

The backscatter channel presents a unique set of challenges. Unlike a conventional one-way communication (in which the information source is also the energy source), the backscatter channel experiences strong self-interference and spread Doppler clutter that mask the information-bearing (modulated) signal scattered from the device. Both of these sources of interference arise from the scattering of the transmitted signal off of objects, both stationary and moving, in the environment. Additionally, the measurement of the location of the backscatter device is negatively affected by both the clutter and the modulation of the signal return.

This work proposes a channel coding framework for the backscatter channel consisting of a bi-static transmitter/receiver pair and a quasi-cooperative transponder. It proposes to use run-length limited coding to mitigate the background self-interference and spread-Doppler clutter with only a small decrease in communication rate. The proposed method applies to both binary phase-shift keying (BPSK) and quadrature-amplitude modulation (QAM) scheme and provides an increase in rate by up to a factor of two compared with previous methods.

Additionally, this work analyzes the use of frequency modulation and bi-phase waveform coding for the transmitted (interrogating) waveform for high precision range estimation of the transponder location. Compared to previous methods, optimal lower range sidelobes are achieved. Moreover, since both the transmitted (interrogating) waveform coding and transponder communication coding result in instantaneous phase modulation of the signal, cross-interference between localization and communication tasks exists. Phase discriminating algorithm is proposed to make it possible to separate the waveform coding from the communication coding, upon reception, and achieve localization with increased signal energy by up to 3 dB compared with previous reported results.

The joint communication-localization framework also enables a low-complexity receiver design because the same radio is used both for localization and communication.

Simulations comparing the performance of different codes corroborate the theoretical results and offer possible trade-off between information rate and clutter mitigation as well as a trade-off between choice of waveform-channel coding pairs. Experimental results from a brass-board microwave system in an indoor environment are also presented and discussed.

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Discourse is a giant field of research and gender related rights are still a disputed area of thinking. Thus, when Arab transnational satellite televisions produce dialogues, images, stories and narratives about the disputed “universal” gender rights in the Middle East, the big questions remain how and why. According to De Beauvoir (1949), one becomes woman and to Butler (1990) one is not born a gender at all but is “done” and “undone” to become one via discourse. Islamic feminism speaks of a cultural/religious specificity in defending women rights and even gender diversity based on new Quranic interpretations. The gender, “Al-Naw’u”, remains synonym to sex “Al Jins” as gender and queer theories never developed in Arabic in tandem with the European institutions or the theories of the19th century– especially those ideas emerging from studies of the mental asylum. This research tries to understand gender related “rights” and “wrongs” as manifest in the discursive institutions owned by media mogul Prince Al Waleed Ben Talal Al Saud. The trouble of such a study is lexical, ideological and institutional at the same time. Since we lack a critique of the discourses and narratives addressed in the pan-Arab satellite channels, in general it is difficult to understand their significance and influence in everyday life practices. What language is used to speak of gender rights or wrongs? Which ideology is favoured in this practice of legitimisation and/or policing? Using case studies, CDA of social and religious talk shows, narrative analysis of Arabic cinemas, this research adapted triangulation to show the complexity of conversing and narrating gender related content at the micro and macro levels within an institution of power. Using semi-structured interviews from fieldwork in Egypt (2009) and Lebanon (2011), archive research and online ethnography, the research exposes the power structure under which gender discourses evolve. It emerges that gender content is abundant on the Pan Arab satellite space, “manufactured” on talk shows and plotted tactfully in the cinematic “creative-act”. The result is a complex discourse of gender content that scratches the surface calling for interpretation. So how and why do gender rights and wrongs find place on Prince Al Waleed’s Media Empire?

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Miniaturization of power generators to the MEMS scale, based on the hydrogen-air fuel cell, is the object of this research. The micro fuel cell approach has been adopted for advantages of both high power and energy densities. On-board hydrogen production/storage and an efficient control scheme that facilitates integration with a fuel cell membrane electrode assembly (MEA) are key elements for micro energy conversion. Millimeter-scale reactors (ca. 10 µL) have been developed, for hydrogen production through hydrolysis of CaH2 and LiAlH4, to yield volumetric energy densities of the order of 200 Whr/L. Passive microfluidic control schemes have been implemented in order to facilitate delivery, self-regulation, and at the same time eliminate bulky auxiliaries that run on parasitic power. One technique uses surface tension to pump water in a microchannel for hydrolysis and is self-regulated, based on load, by back pressure from accumulated hydrogen acting on a gas-liquid microvalve. This control scheme improves uniformity of power delivery during long periods of lower power demand, with fast switching to mass transport regime on the order of seconds, thus providing peak power density of up to 391.85 W/L. Another method takes advantage of water recovery by backward transport through the MEA, of water vapor that is generated at the cathode half-cell reaction. This regulation-free scheme increases available reactor volume to yield energy density of 313 Whr/L, and provides peak power density of 104 W/L. Prototype devices have been tested for a range of duty periods from 2-24 hours, with multiple switching of power demand in order to establish operation across multiple regimes. Issues identified as critical to the realization of the integrated power MEMS include effects of water transport and byproduct hydrate swelling on hydrogen production in the micro reactor, and ambient relative humidity on fuel cell performance.

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This is a qualitative case study of the adoption of a currency board in Argentina in 1991. It presents a discursive analysis and intellectual history of four overlaying and mutually influencing stories of Convertibility’s adoption. It is (1) the story of how Menem aligned himself to the Washington Consensus as a means to win a Presidential election. This ideological alignment influences and is influenced by a (2) reconstitution of the Peronist Party’s historically entrenched identity. This in turn re-fashion the whole system of interest articulation and relative power of interest groups in Argentina. The adoption of a currency board also marks the pace of (3) the entrenchment neoliberal interests across a domestic network of neoliberal think-tanks, technocrats, politicians, and “technopoles” articulating neoliberal interests outside of the Washington Consensus, within an International Neoliberal Network. Argentina’s adoption of a currency board falls in line with the Corner Solutions, a neoliberal doctrine promoted to influence developing countries to adopt two forms of exchange rate regimes that allow for less government involvement, including a currency board. Argentina starts as a test country and then becomes (4) an ideological stepping stone to help promote the creation of currency boards across more “developing” countries. These stories are not sequential but concurrent, and they help advance an alternative critique of neoliberalism that focuses on specifics to induce case-specific lessons versus a theory claiming to provide any universal truth.

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Regulated Transformer Rectifier Units contain several power electronic boards to facilitate AC to DC power conversion. As these units become smaller, the number of devices on each board increases while their distance from each other decreases, making active cooling essential to maintaining reliable operation. Although it is widely accepted that liquid is a far superior heat transfer medium to air, the latter is still capable of yielding low device operating temperatures with proper heat sink and airflow design. The purpose of this study is to describe the models and methods used to design and build the thermal management system for one of the power electronic boards in a compact, high power regulated transformer rectifier unit. Maximum device temperature, available pressure drop and manufacturability were assessed when selecting the final design for testing. Once constructed, the thermal management system’s performance was experimentally verified at three different power levels.

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As its title indicates, this book, which is divided into four chapters, seeks to provide an overview of “the diverse political, social and cultural functions that interfaith marriage alliances and other sexual encounters fulfilled within the overall dynamic of Christian- Muslim relations in the Iberian Peninsula during the medieval period, both within al- Andalus (…) and the expansionist Christian-dominated polities of the North” (4). In this sense, its chronological span reaches from the early eighth century (the conquest of the Iberian Peninsula by the Muslims) to 1492 (the Christian conquest of the Nasrid Kingdom of Granada)

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