• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.42-45
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• 2001

Switched Reluctance Motors(SRM) are a promising candidated automotive drives of the next generations. The successful commercialization of SRM drives in automobiles depends highly on the developments of SRM design and control techniques. This paper descrives the control issues of SRMs, ranging from drive system structure, rotor position sensing and torque control. Both simulation studies and test results are presented for a 160W SRM drive for automotive application.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.7
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• pp.966-973
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• 2012

In microgrid demonstration site, distributed generations can make bidirectional power flows on the system. If an accident occurs, the fault current from the inverter based distributed generation is small. However, the conventional protection scheme in distribution network is designed to operate at high fault current. This means that the traditional protection of distribution network is no longer applicable and new protection methods must be developed. In this paper, for two cases, algorithms for protection coordination of demonstration site is proposed and verified through PSCAD/EMTDC simulation. In first case, protection devices are assumed to have the abilities of directional relaying and communication. In second case, protection devices do not have those abilities. Proposed protection coordination algorithms detect the fault locations and protect the microgrid fairly well.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.816-817
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• 2007

As UNFCC(United Nations Framework Convention on Climate Change) is enhanced, Korea will perform a CO2 reduction duty. The CO2 reduction duty will effect Korea power system because coal and oil thermal generations emit large CO2 form about 46% of total CO2 emission. Moreover various alternatives should be designed to comply with CO2 reduction duty. In this paper, we analysis resource planning considering CO2 emission constraints and emission trading. And we analysis resource planning under using LP(Linear Programing) and MIP(Mixed Integer Programing).

• Journal of Surface Science and Engineering
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• v.14 no.4
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• pp.221-233
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• 1981

Section 102(2) (c) of the National Environmental Policy Act of 1969 of the United States requires an environmental assessment of the major federal actions that could significantly a-ffect environmental quality. The review is known as the NEPA assessment process, and the resulting document is called an Environmental Impact Assessment (EIS). Article 5 of the En-vironmental Preservation Law of ROK also introduced this system to a cereain extent. The purpose of this paper is, therefore, to review the general impacts of environmental pollution caused by newly proposed actions on air quality, water resources, and land use as well as specific impacts from the disposal of radiation wastes, operation of petroleum and ru-bber industries, construction of highways and dams, location of power plants and industrial co-mplexes, etc., in order to fully understand the importance of this system. Differences between American and Korean system are also briefly studied and reached to a conclusion that this important system should be understood in such a way as to link and uti-lize all conceivable disciplines and human knowledge in order to protect our environment by all means for ourselves and our coming generations as well.

• Journal of Institute of Convergence Technology
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• v.2 no.1
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• pp.7-12
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• 2012

Spent fuels are discharged from nuclear reactors as a result of power generations. The spent fuels would be considered as a useful resources because the main constituent is uranium and some other actinides are included in them. In order to utilize the resources chemical processes should be developed to treat the spent fuels and obtain uranium and other actinides to be fueled in a fast reactor. The technologies are categorized into wet and dry processes. In this study, the current status of such technologies is summarized to give a insight and a deep understanding on nuclear fuel cycles.

• Proceedings of the KIEE Conference
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• summer
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• pp.42-44
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• 2004

This paper introduced and proposed the voltage unbalance of DC terminal output as new monitoring parameter for power islanding detection. This paper also presented a simple and novel detection algorithm, which effectively combines the detection results of the conventional parameter, voltage magnitude, and a newly proposed parameter. We tested the proposed method using several distribution network conditions including not only islanding operation conditions, but also non-islanding conditions of normal network load variations. The test results showed that the proposed parameters and algorithm are capable of correctly detecting the islanding operation not affected by variation of DG loading and also have a good selectivity for islanding conditions and non-islanding conditions.

• SUVANNABHUMI
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• v.16 no.2
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• pp.67-90
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• 2024

This article paid attention to three types of children's characters in Vietnamese children's literature in North Vietnam from 1945 to 1975, including children's characters as young soldiers in the frontlines, young citizens in daily life, and role models. The goal of this body of literature was illustrated as educating young generations on patriotism, the revolutionary spirit, and civic consciousness. Our research suggests that politics in children's literature is universal and that the power discourse of adults is an inevitable factor predominating in children's literature. Besides, juxtaposing Vietnamese children's literature with Southeast Asian literature helps us see that the political orientation and moral concepts in children's literature have created a stagnation in the current pace of Vietnamese children's literature. This paper, therefore, contributes to identifying Vietnamese children's literature in the overall picture of Southeast Asian children's literature in the post-colonial context.

• Journal of Wind Energy
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• v.15 no.1
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• pp.5-10
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• 2024

Offshore wind power generation has significant advantages, including enhanced energy security and job creation. However, despite these benefits, South Korea has not fully utilized its potential in this sector. In contrast, offshore wind power industry development in Europe has been driven by government leadership. Drawing from this experience, South Korea also needs to relax regulations, strengthen necessary infrastructure, and enhance financial support systems to activate the offshore wind power industry. For this, sustained government leadership is absolutely essential. Without addressing the capacity issues in the power grid, we cannot expect offshore wind power generation to succeed. To address grid issues, we propose the enactment of a special law called the "Special Act on Grid Expansion." Considering KEPCO's financial situation, private investment should be encouraged for grid construction. The role of developers is crucial for the successful development and operation of offshore wind power. They manage risks throughout various stages, from site acquisition to construction and operation, which have a significant impact on the success or failure of projects. Since domestic developers currently lack experience in offshore wind power, a cooperative strategy that leverages the experience and technology of advanced countries is necessary. Energy issues should be recognized as important tasks beyond mere political ideologies, as they are crucial for the survival of the nation and its development. It is essential to form a public consensus and implement ways for residents to coexist with offshore wind power, along with the conservation of marine ecosystems and effective communication with stakeholders. Expansion of the offshore wind power industry requires support in various areas, including financial and tax incentives, technology research investment, and workforce development. In particular, achieving carbon neutrality by 2050 necessitates the activation of offshore wind power alongside efforts by major corporations to transition to renewable energy. South Korea, surrounded by the sea, holds significant offshore wind power potential, and it is our responsibility to harness it as a sustainable energy source for future generations. To activate the offshore wind power market, we need to provide financial and tax support, develop infrastructure and research, and foster a skilled workforce. As major corporations transition to renewable energy to achieve carbon neutrality by 2050, offshore wind power must play a significant role. It is our responsibility to fully utilize South Korea's potential and make offshore wind power a new driver of growth.

• Proceedings of the KIEE Conference
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• 2004.11b
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• pp.190-193
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• 2004

Optimal Power Flow (OPF) is becoming more and more important in the deregulation environment of power pool and there is an urgent need of faster solution technique for on-line application. So this paper presents parallel genetic algorithm-tap search for the solution of the OPF. The control variables modeled unit active power outputs, generator-bus voltage magnitudes and transformer-tap settings. A number of functional operating constraints, such as branch flow limits, load bus boltage magnitude limits and generator reactive capabilities are included as penalties in the fitness function. In parallel GA-TS, GA operators are executed for each process. If best fitness of the GA is not changed for several generations, TS operators are executed for the upper three populations to enhance the local searching capabilities. With migration operation, best string of each node is transferred to the neighboring node after predetermined iterations are executed. For parallel computing, we developed a PC-cluster system consisting of 8 PCs. Each PC employs the 2 GHz Pentium IV CPU and is connected with others through ethernet switch based fast ethernet. To show the usefulness of the proposed method, developed algorithm has been tested and compared on an IEEE 30-bus system in the reference paper. From the simulation results, we can find that the proposed algorithm is efficient for the OPF.

• Environmental Engineering Research
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• v.23 no.4
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• pp.383-389
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• 2018

Microbial fuel cell (MFC) is an innovative environmental and energy system that converts organic wastewater into electrical energy. For practical implementation of MFC as a wastewater treatment process, a number of limitations need to be overcome. Improving cathodic performance is one of major challenges, and introduction of a current collector can be an easy and practical solution. In this study, three types of current collectors made of stainless steel (SS) were tested in a single-chamber cubic MFC. The three current collectors had different contact areas to the cathode (P $1.0cm^2$; PC $4.3cm^2$; PM $6.5cm^2$) and increasing the contacting area enhanced the power and current generations and coulombic and energy recoveries by mainly decreasing cathodic charge transfer impedance. Application of the SS mesh to the cathode (PM) improved maximum power density, optimum current density and maximum current density by 8.8%, 3.6% and 6.7%, respectively, comparing with P of no SS mesh. The SS mesh decreased cathodic polarization resistance by up to 16%, and cathodic charge transfer impedance by up to 39%, possibly because the SS mesh enhanced electron transport and oxygen reduction reaction. However, application of the SS mesh had little effect on ohmic impedance.