• Title/Summary/Keyword: power-laws

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Theoretical Characteristics of Thermodynamic Performance of Combined Heat and Power Generation with Parallel Circuit using Organic Rankine Cycle (유기랭킨사이클을 이용한 병렬 열병합 발전시스템의 열역학적 이론 성능 특성)

  • Kim, Kyoung-Hoon
    • Journal of the Korean Solar Energy Society
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    • v.31 no.6
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    • pp.49-56
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    • 2011
  • In this study a novel cogeneration system driven by low-temperature sources at a temperature level below $190^{\circ}C$ is investigated by first and second laws of thermodynamics. The system consists of Organic Rankine Cycle(ORC) and an additional heat generation as a parallel circuit. Seven working fluids of R143a, R22, R134a, R152a, $iC_4H_{10}$(isobutane), $C_4H_{10}$(butane), and R123a are considered in this work. Maximum mass flow rate of a working fluid relative to that of the source fluid and optimum turbine inlet pressure are considered to extract maximum power from the source. Results show that due to a combined heat and power generation, both the efficiencies by first and second laws can be significantly increased in comparison to a power generation, however, the second law efficiency is more resonable in the investigation of cogeneration systems. Results also show that the working fluid for the maximum system efficiency depends on the source temperature.

A Status of Safety Control Laws in Laboratory for Use of Nuclear Material (핵물질 사용 실험실의 안전관리 법령 현황)

  • Ji, Cheol-Gu;Bae, Sang-O;Kim, Jeong-Do
    • Proceedings of the Safety Management and Science Conference
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    • 2011.11a
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    • pp.85-91
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    • 2011
  • Safety in the nuclear facility has been a growing interest due to recent recurrences of the fatal accidents such as Fukushima accident and Chernobyl accident. It is not easy to determine the extent to what technical requirements of nuclear facility such as nuclear power plant are be likely applicable to the laboratory for use of nuclear material. All of workers in nuclear shall be recognized for the generic features of safety according to the related laws. This study surveys a status of safety control laws to enhance safety in laboratory for use of nuclear material.

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The Strategy of Russia's Political Elites to Maintain Dominance Through the Overhaul of Electoral System (선거제도 개편을 통한 러시아 정치 엘리트의 지배력 유지 전략)

  • Siheon Kim;Seho Jang
    • Analyses & Alternatives
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    • v.7 no.1
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    • pp.7-43
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    • 2023
  • This study examines and identified a series of strategies of Russia's political elites to maintain and strengthen their dominance by reviewing the case of revisions in the election laws of Russia in 2014. At that time, a mixed-member electoral system was newly introduced, and on the surface, it seemed that the new system was a step toward meeting the demands of the people for "enhanced democracy". However, in 2016 and 2021, the ruling party of Russia won the general elections by making the most of the factors that could distort the election results inherent in the mixed-member electoral system. Therefore, this study aimed to analyze whether the revision of election laws was a mere vehicle used by the ruling party, United Russia, to maintain its political power, or whether it was a leap forward to achieve democracy. The study result indicate that the revision of election laws in 2014 was part of the policy responses to the internal conflicts in the circle of Russia's political elites, which had been rising since 2008, as well as to the public resistance. In other words, it was confirmed that the revision of election laws was one of the measures taken to "minimize competition" and "reproduce political power on a stable basis".

Control Methods of the Pulse-Width Modualted Series Resonant Converter(PWN-SRC) (펄스폭 변조 직렬공진 컨버터의 제어연구)

  • 최현철
    • The Transactions of the Korean Institute of Power Electronics
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    • v.4 no.5
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    • pp.397-404
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    • 1999
  • In this paper, several control methods for the discontinuous mode PWlvl-SRC are investigated with the l linearized small signal model. In order to analyze the stability and dyncunic characteristics of the controlled s system, the root locus as a function of the normaliz떠 output current(]\iOC) for a given normalized output v voltage(NOV) is employed. FurLhem10re, in this paper, the “Optimal trajectory control of PWM-SRC" is newly p propos(xl and its good dvnamic performances are evaluated with other four control laws.laws.

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Survey for Renewable Energy Policy of Japan and China (일본과 중국의 신재생에너지정책 조사 연구)

  • Jang, Woon-Jeong;Jeon, Mi-Hwa;Kim, Yoon-Kyung
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.289-292
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    • 2009
  • This paper reviewed laws and policies of renewable energy in Japan and China. Japan has enacted laws and implemented policies of renewable energy since 1980 for their energy security and environmental problem, and nowadays renewable energy is one of solutions for UNFCCC and Kyoto Protocol. Japan plays a leading role in photovoltaic power generation. As second largest energy consumer, China generates a lot of pollution from their energy use. However Chinese government attempts to sustainable development among economy, society and environment, suggests to use renewable energy in the way to reduce pollution and improve living standards. Korea focused on renewable energy as one of motive power in Green Growth. Review for renewable energy policy of two countries gives Korean policy implication and helps "Green Growth", national theme of Korea.

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Conceptual Design Based on Scale Laws and Algorithms Sub-critical Transmutation Reactors

  • Lee, Kwang-Gu;Chang, Soon-Heung
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.10a
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    • pp.475-480
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    • 1997
  • In order to conduct the effective integration of computer-aided conceptual design for integrated nuclear power reactor, not only is a smooth information flow required, but also decision making fur both conceptual design and construction process design must be synthesized. In addition to the aboves, the relations between the one step and another step and the methodologies to optimize the decision variables are verified, in this paper especially, that is, scaling laws and scaling criteria. In the respect with the running of the system, the integrated optimization process is proposed in which decisions concerning both conceptual design are simultaneously made. According to the proposed reactor types and power levels, an integrated optimization problems are formulated. This optimization is expressed as a multi-objective optimization problem. The algorithm for solving the problem is also presented. The proposed method is applied to designing a integrated sub-critical reactors.

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CONTINUATION THEOREMS OF THE EXTREMES UNDER POWER NORMALIZATION

  • Barakat, H.M.;Nigm, E.M.;El-Adll, M.E.
    • Journal of applied mathematics & informatics
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    • v.10 no.1_2
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    • pp.1-15
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    • 2002
  • In this paper an important stability property of the extremes under power normalizations is discussed. It is proved that the restricted convergence of the Power normalized extremes on an arbitrary nondegenerate interval implies the weak convergence. Moreover, this implication, in an important practical situation, is obtained when the sample size is considered as a random variable distributed geometrically with mean n.

Suggestions to Improve the Effectiveness of National Radiological Emergency Response System (국내 방사능재난대응체계 실효성 제고를 위한 제언)

  • Moon, Joo Hyun
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.2
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    • pp.195-206
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    • 2020
  • Although the national radiological emergency response system has been improved by incorporating lessons from the Fukushima nuclear power plant accident and recent domestic natural disasters, it has not fully incorporated these lessons. In addition, it cannot deal with a variety of aftermath of the radiological disaster. Even for the same disaster, the national emergency response system should comply with multiple domestic laws in our country. Furthermore, there are a few discrepancies between the articles of the domestic laws that the national radiological emergency response system should address. Therefore, this study investigates the characteristics of radiological disasters, examines articles on the domestic laws related to the national radiological emergency response system, and analyses the Japanese government's responses to the Fukushima nuclear power plant accident. Based on the results of the review, suggestions for the improvement of the national radiological emergency response system in terms of response organization and framework have been proposed in this study.

Review for the Enactment of Anti-Terrorism Law in China: Comparing it to those in the USA, Britain and Germany (중국의 반(反)테러리즘법 제정을 위한 검토: 미국.영국.독일과 비교하여)

  • Lee, Dae Sung;Ahn, Young Kyu
    • Convergence Security Journal
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    • v.14 no.6_1
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    • pp.45-55
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    • 2014
  • China has vast land, variety of people, religions and cultures. China has faced terrorism threat from the struggles of people, religions and resources. The 11thStanding Committee of the National People's Congress of China decided to strengthen the anti-terrorism action on October 29, 2011. This study compared, analyzed and estimated the counter-terrorism laws of the USA, Britain and Germany thinking about the China's anti-terrorism decision. The counter-terrorism laws of the USA, Britain and Germany are largely composed of previous prevention of terror and oppression of it later. They enacted the laws both for people and property. They also rearranged the power and role of governmental institutes on counter-terrorism. The contents of the counter-terrorism laws are specific, detailed and systematic. But the anti-terrorism law of China has restriction on the power and roles for previous prevention and oppression of terrorism, handling of people and property. This study reviewed the foreign countries' counter-terrorism laws and the way to connect the regulations on terrorism crimes of the revised Chinese criminal law and the anti-terrorism decision, when they enact the anti-terrorism laws in China in the future.