• Journal of Advanced Navigation Technology
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• v.18 no.3
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• pp.248-252
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• 2014

In this paper, press and nut runner used in press-fit or tightening the bolts and nuts at assembling process of automobile parts companies continually demand accuracy and improved productivity. Simultaneous control of production systems through synchronization configuring of the combination multi press-fit system developed multi servo press system using the low-speed serial communication. As a result, the accuracy and the productivity is improved and product quality improvement could be achieved.

• Journal of Power Electronics
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• v.3 no.2
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• pp.81-89
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• 2003

The global electrical energy consumption is still rising and there is a steady demand to increase the power capacity, to produce, distribute and use the energy as0 efficient as possible and furthermore to set up incentives to save energy at the md-user. Two major technologies will play important roles to fulfill those targets. One is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficiency power electronics in power systems for high efficiency and high performance applications. This paper discusses both areas, in particular the power electronic application in wind power integration.

• Proceedings of the KIPE Conference
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• 2004.07a
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• pp.446-450
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• 2004

The amount of electric energy used in a vehicle will be increased continuously. The increment of electric power demand causes interest on new higher power system such as 42V Power Net. Furthermore, the necessity for development of energy storage device is highlighted recently. Bidirectional nm Converter is one of the important parts in 42V power system. Therefore, this paper proposes bidirectional Cascade Buck-Boost DC/DC Converter which can satisfies required specifications in 42V power system The operation principle is described along with simple control method, and experimental results on a 500W prototype are provided.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.1
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• pp.67-72
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• 2004

This paper addresses the bidding strategies of generating firms in a competitive market where the firms are provided with payment for generating reactive power. Reactive support for voltage control is an integral and critical part of power system operations. Since reactive support is unbundled in a competitive market under open access transmission, it is treated as one of ancillary services. The operation costs and opportunity costs for reactive support are compensated by payment to the firms, hence their bidding strategies will be affected. The opportunity costs are evaluated from the foregone profits of a generator in making sales in real power market by providing reactive support instead of real power. Game theory approach is used to analysis the transaction strategies of real power by the bimatrix method in this paper. Through computing the Nash equilibrium in a sample system, an incentive of a generator for improving the reactive generating capacity is found to be effective and the variations of the profits are analyzed as the demand power factor changes.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.127-129
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• 2005

Construction of wind power plant is increasing rapidly because Jeju island is known as the most suitable place for wind power plant. Rut wind power plant is difficult electric power control and it has a rapid electric power fluctuation. Such a problem has a bad influence on electric power network in small electric network like Jeju. Therefore, we forecast the amount of wind power plant construction by weather information and the rate of utilization for existing facility. We investigate the contribution degree for electric Power demand, economic effect, the case of power network influence. So we forecast influence of wind power plant for Jeju power network's operation in the near future.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.1266-1273
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• 2004

Urban railway signaling system is for train operation with safety in the urban crowded area, that has been increasing the demand of use of advanced train control systems with safe. European Commission is supporting the UGTMS(Urban Guided Transport Management System) project for the research and development. The main objective of UGTMS is to provide the European urban guided transport sector (comprising metro, tram and light rail systems) with a common Management System. A key topic is the extent to which the specifications for the successful ERTMS(European Rail Transport Management System) can be adapted to UGTMS needs. Beyond this, it is necessary to define the relevant functional and system requirements for all types of urban guided transport management systems in order to improve interoperability and intermodality. Also to be explored are the prospects for open system standards. In this article, we look into the trend of the standardization through the UGTMS project in Europe and consider any benefit to the project of the standardization for the urban railway signaling system in Korea.

• Proceedings of the KSR Conference
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• 2003.10b
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• pp.311-318
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• 2003

Traffic management means the management of streams of people, vehicle and cargo. Its aim is to help creating an efficient, safe and environmentally friendly transport system. Traffic management can roughly be divided in traffic control and monitoring, traffic information and demand management. The main purpose of this thesis is providing the basis for developing the next generation train traffic management system by comparing domestic and abroad train traffic management system. The composition of this thesis has been discussed in the following order of the comparison of train traffic management system's function, the introduction of Autonomous Decentralized system, the comparison between CTC and ATOS. the comparison between the hierarchy system and Autonomous Decentralized system, the study of introduction plan of Autonomous Decentralized-type train traffic management system and conclusion.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.2
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• pp.116-125
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• 2003

The new HVAC system to lower the conveyance energy and building height using IAV (Increasing Air Volume) technique is developed. IAV units which are equipped in each zone carry out air-conditioning and supply fresh air by induction of outdoor air in main duct. The design program which decides size of OAHU and IAV unit according to air conditioning load and fresh air demand of each zone is presented. The control system is developed to operate efficiently HVAC system and IAV unit, so that individual zone operation and well-deal with partial load and IAQ problem are possible. The new system is investigated in model building and makes more profit in conveyance energy, size of air conditioning facilities room and building height than VAV system. But in construction cost it is worse by about 15 per-centage.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.4
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• pp.23-29
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• 1999

The effect of dilute sulfuric acid treatment was examined to improve recyclability of coated brokes. Turbidity , electric conductivity , and cationic demand of the white water from coated broke prepared from an alkaline base paper was determined. Sulfuric acid treatment was found to be effective in dissolving undisintegrated substances such as binders, pigments, and fibers. The properties of papers prepared by adding the broke to pulp stock up to 30% dry weight were examined . With the increase of broke addition, retention, sizing degree and smoothness were improved ; on the other hand, formation uniformness, air permeability and internal bonding strength were decreased. The extent of improvement by broke addition was greater for the surfuric acid-treated broke than the control broke. It was concluded that the use of coated broke should be limited within 10-15% weight of the product for either type of broke.

• Journal of Wetlands Research
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• v.10 no.3
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• pp.47-56
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• 2008

This paper sought to provide information regarding the water resources in the Philippines, focusing on the issues of water quality, status of water use and water scarcity, and other threats to water availability. Although the country has sufficient amount of water resources, it was found out that water availability is still threatened by some major water resources problems: increasing water demand due to drastic growth in population, water resources pollution, droughts and flooding and weak institutional framework to address these problems. Water quality problems include increasing groundwater and surface water pollution. Moreover, drought and flooding have also increased damages in recent years due to deteriorating watersheds and high economic and population growth. In relation to these, the government enacted national laws to define and deal with water control and quality management. The objective of this research was to present and evaluate current conditions and issues on Philippine water resources.