• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• 제1권1호
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• pp.75-82
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• 1987

Application of conventional phase controlled power electronic circuits causes reduced power factor and increased harmonic component in the electric sources. Therefore, an Optimal PWM strategy has been investigated here in order to reduce to a large extent these effects mentioned. Optimal PWM converter has been to minimize the rms harmonic current in the sources and has been found to have a duality with Optimal PWM inverter. The voltage patterns of Optimal PWM Inverters are governed by the same switching patterns and control laws as the current patterns for Optimal PWM converter. The improvement requires switching devices having a high speed capability. While this formerly did require thyristors with force commutation circuits, today this feature is easily implemented by using power Transistor or GTOs. The control laws for minimizing the rms harmonics current in the source, the circuits and the results are shown in the paper.

• Nuclear Engineering and Technology
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• 제55권9호
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• pp.3409-3416
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• 2023

Licensing the next-generation of nuclear reactor designs requires extensive use of Modeling and Simulation (M&S) to investigate system response to many operational conditions, identify possible accidental scenarios and predict their evolution to undesirable consequences that are to be prevented or mitigated via the deployment of adequate safety barriers. Deep Learning (DL) and Artificial Intelligence (AI) can support M&S computationally by providing surrogates of the complex multi-physics high-fidelity models used for design. However, DL and AI are, generally, low-fidelity 'black-box' models that do not assure any structure based on physical laws and constraints, and may, thus, lack interpretability and accuracy of the results. This poses limitations on their credibility and doubts about their adoption for the safety assessment and licensing of novel reactor designs. In this regard, Physics Informed Neural Networks (PINNs) are receiving growing attention for their ability to integrate fundamental physics laws and domain knowledge in the neural networks, thus assuring credible generalization capabilities and credible predictions. This paper presents the use of PINNs as surrogate models for accidental scenarios simulation in Nuclear Power Plants (NPPs). A case study of a Loss of Heat Sink (LOHS) accidental scenario in a Nuclear Battery (NB), a unique class of transportable, plug-and-play microreactors, is considered. A PINN is developed and compared with a Deep Neural Network (DNN). The results show the advantages of PINNs in providing accurate solutions, avoiding overfitting, underfitting and intrinsically ensuring physics-consistent results.

• Journal of Power Electronics
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• 제16권2호
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• pp.584-597
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• 2016

This paper focuses on an improvement in the transient performance of Boost converters when the load changes abruptly. This is achieved on the basis of the nature trajectory in Boost converters. Three key aspects of the transient performance are analyzed including the storage energy change law in the inductors and capacitors of converters during the transient process, the ideal minimum voltage deviation in the transient process, and the minimum voltage deviation control trajectory. The changing relationship curve between the voltage deviation and the recovery time is depicted through analysis and simulations when the load suddenly increases. In addition, the relationship curve between the current fluctuation and the recovery time is obtained when the load suddenly decreases. Considering the aspects of an increasing and decreasing load, this paper proposes the transient performance synthetic optimized trajectory and control laws. Through simulation and experimental results, the transient performances are compared with the other typical three control methods, and the ability of proposed synthetic trajectory and control law to achieve optimal transient performance is verified.

• The Transactions of the Korean Institute of Power Electronics
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• 제6권5호
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• pp.377-385
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• 2001

The mixed gas of Hydrogen and Oxygen is gained from water electrolysis reaction. It has constant volume ratio 2 : 1 Hydrogen and Oxygen, and it is used as a source of thermal energy by combustion reaction. This gas has better characteristics in the field of economy, efficiency of energy, and environmental intimacy than acetylene gas and LPG used for gas welding machine. So several studies of this gas are actively in progress nowadays. The object of this study is the optimization of power condition in the side of electricity for the Hydrogen-Oxygen gas generator, Firstly chemical analysis of electrolysis is conducted, and the relation of electrical energy and chemical energy is quantitatively investigated through Faraday's laws of electrolysis. After that, pulse power supply is designed for basic experiment which could be applied to the analysis of Hydrogen-Oxygen gas generator. In the basis of above steps, comparison and analysis of Hydrogen-Oxygen gas generator was conducted as variable frequency using pulse Power supply.

• The Journal of Fisheries Business Administration
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• 제54권2호
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• pp.59-76
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• 2023

This study is to propose ways to improve the system for rational procedures for offshore wind power generation projects. The results of this study are summarized as follows. In order to quickly distribute and develop offshore wind power projects, the permitting period should be shortened through special laws, the government actively intervenes to support the formation and operation of privat-public councils to ensure residents' acceptance. In this way, it can be competitive in the future energy market. Above all, a special law (proposal) related to offshore wind power currently pending in the National Assembly should be passed as soon as possible. Finally, the government and local governments that manage public waters should provide active administrative support based on system improvement measures in consideration of these permits, and the project's main body should minimize damage to the marine environment and ecosystem. Through these subject-specific roles, offshore wind power generation will be able to reduce carbon emissions and help establish a sustainable energy production system.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• 제4권1호
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• pp.54-62
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• 1990

This paper shows a reasonable design standard of Demand Factor and Diversity Factor for buildings, that was made by the systematic and statistical way considering actual conditions, such as investicated electric equipment capacity, electric power consumption, etc. The saving of electric equipment investment, the decrease of power loss, the improvement of facilities utilization and the decrease of electric power rates, can be contributed by the application of the design standard. The recommended design standard must be applied by the revision of current regulations and laws.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• 제6권6호
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• pp.42-48
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• 1992

This paper shows a reasonable design standard of substation facility density and demand factor in office buildings, that was made by the systematic and statistical way considering actual conditions, such as investigated electric equipment capacity, electric power consumption, etc for 121 buildings. The saving of electric equipment investment, the decrease of power loss, the improvement of facilities utilization and the decrease of electric power rates an be contributed by the application of the design standard must be applied by the revision of current regulations and laws.

• Journal of Arbitration Studies
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• 제18권2호
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• pp.103-127
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• 2008

This paper is to research the powers and interim measures of the arbitral tribunal in the arbitral proceedings of the international commercial arbitration under arbitration legislation and arbitration rules including the UNCITRAL Model Law and Arbitration Rules. The powers of the arbitral tribunal may be found within the arbitration agreement or any arbitration rules chosen by the parties, or the chosen procedural law. The power of the arbitral tribunal to decide its own jurisdiction is one of the fundamental principles of international commercial arbitration. It is a power which is now found in nearly all modern arbitration and rules of arbitration. Where an arbitral tribunal has been appointed then it will usually have the power to proceed with the arbitration in the event that a party fails to appear. It cannot force a party to attend but it may sanction the failure. While the arbitral tribunal can direct the parties to attend and give evidence the arbitral tribunal has no power to compel a party to give evidence. The arbitral tribunal may continue the arbitration in the absence of the party or its failure to submit evidence and make an award on the evidence before it. Under most of arbitration legislation and arbitration rules, the arbitral tribunal has the power to appoint experts and obtain expert evidence. The power to order a party to disclose documents in its possession is a power given to the arbitral tribunal by many national laws and by most arbitration rules. The arbitral tribunal cannot, however, compel disclosure and in the case where a party refuses to disclosure documents then the sanctions that the arbitral tribunal can impose must be ascertained from the applicable rules or the relevant procedural law. A number of arbitration rules and national laws allow for the arbitral tribunal to correct errors within the award. Most of arbitration legislation and arbitration rules permit the arbitral tribunal to grant orders for interim measure of protection. Article 17(1) of the Revised UNCITRAL Model Law of 2006 states: Unless otherwise agreed by the parties, the arbitral tribunal may, at the request of a party, grant interim measures. Interim measures of protection usually take such forms as (1) conservatory measures intended to prevent irreparable damage and maintain the status quo; (2) conservatory measures intended to preserve evidence or assets. Orders for interim measures by the arbitral tribunal are not self-enforcing. However, the arbitral tribunal must have the powers necessary to make interim measures effective. The Article 17 B of the Revised UNCITRAL Model Law of 2006 provides applications for preliminary orders and conditions for granting preliminary orders. And the Article 17 H provides recognition of enforcement of interim measures. In conclusion, the revised articles with regard to interim measures of the UNCITRAL Model Law of 2006 would contribute significantly to the security of the effectiveness of interim measures in international commercial arbitration. Therefore, Korean Arbitration Law and Arbitration Rules would be desirable to admit such revised articles with regard interim measures.

• Nuclear Engineering and Technology
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• 제41권4호
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• pp.545-548
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• 2009

Korean utility has utilized a Periodic Safety Review (PSR) that assesses the cumulative effects of plant aging, modifications, operating experience, technical developments, and site characteristics since 2000. In particular, the assessment and management of plant aging is one of the major areas in PSR. It includes identification of critical Systems, Structures, and Components (SSCs) for aging, assessment of aging effects, and implementation of aging management programs. Since the PSR system was introduced based on the atomic energy acts and related laws, PSRs of eight sets for 12 Nuclear Power Plants (NPPs) that have been operating more than 10 years have been completed. PSRs of two sets for 4 NPPs are currently being carried out. The utility has confirmed that domestic NPPs have been operated safely through these PSRs and have implemented the follow-up corrective activities to increase the nuclear safety. In this paper, the status of PSR implementation is discussed and improvement programs to conduct PSR follow-up corrective activities efficiently for NPPs are suggested based on experiences with aging assessments.

• Journal of the Korean Professional Engineers Association
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• 제41권4호
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• pp.32-37
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• 2008

This Report intends theoretical background of urban planning, related national law system and instances to be researched and concluded as follows below and also to be shared with planners working in the field of urban planning technique services. Revision of new laws and systems are necessary for the reasonable Urban Regeneration promotion through comprehensive and systematic supporting composition revision. For the reason hereafter urban regeneration shall be various and inclusive in society, economy, culture, environment, resident participation. etc., the development model for regeneration project complying with Korean Urban Regeneration condition is required. Diversity and flexibility through governance system are required to ensure city competitive power.