• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.60-70
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• 1997

Since, human error is a major factor contributing to disaster during start-up of operation in Boiler plant. it is necessary to develop an automation system which prevent mode of operation that are known to be dangerous and to bring a loss of energy. The aim of this study is to suggest a model for the computer-aided synthesis of operation sequence as a part of automation system for start-up operation. Synthesis is accomplished by the formation of a hierarchical network of goals which decide sequence of operations. Hierarchical Network is formed by using method which upper goals ( i.e. upper operation al situation) are classified by the function of themselves into lower goals (i.e. lower operational situation). Knowledge for deciding operation sequence is generated by putting In order the knowledge of hazard operation and energy management.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.11
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• pp.61-68
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• 2009

A Microgrid is a private small-scale power system composed of distributed energy resources (DERs), storage devices and loads. And it is expected that the Microgrid will come into wide use in the near future. For this, the establishment of the Microgrid operation methodology is a very important problem. Especially, the Microgrid is greatly different from existing private small-scale power systems because of the multiple participants. Therefore, the Microgrid operation considered various requirements according to multiple participants is more complicated than the operation of existing private small-scale power systems. In this paper, Microgrid operation methodology based on a market environment is suggested. Through case studies, the effectiveness of the suggested methodology is verified.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.29-31
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• 2002

Purpose of the 765kV trial operation conducted for the first time in our country are performance verification of domestic developed equipment(765kV M.Tr, GIS,etc) and extraction of problem in advance to commercial operation and cultivation of operation ability. The trial operation of 765kV substation was finished successfully under the positive supports of institutes. manufactures. and constructers. It is expected that extraction of problems in advance and accumulation of operation techniques through the trial operation of 765kV substation will be contributed largly to the realization of the without a hitch operation of 765kV system.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.23-24
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• 2000

A new PDP cell structure called CSP (Charge Storage Pad) improves the luminous efficiency by 1.6 times and prevents cross talk between adjacent cells. The CSP, which is a conducting material, is inserted between the dielectric layer and the MgO film in the front plate. This CSP produces a longer time-averaged discharge path to get a high luminous efficiency and confines the discharge to prevent cross talk.

• Journal of the Korean Society for Railway
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• v.9 no.1 s.32
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• pp.29-35
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• 2006

Trains in LRT(Light Railway Transit) system usually have shorter car length than metro's because of their smaller passensers demand. Therefore it is very likely that the load condition of LRT system in abnormal operation, in case of which trains are in close proximity by system broke or train rescue works, could be worse rather than in normal operation, in spite of rare probability of abnormal operation. In this study, the target reliability indexes of several abnormal operations are estimated in accordance with the occurrence probabilities of each abnormal operation case and the reliability index of normal operation presented by the specification. From the indexes, load factors for the abnormal operation cases are estimated and the safety evaluation is performed for Yong-in LRT project.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.329-332
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• 2005

Distributed generation (DG) systems fall in islanding operation when they still in operation even when the main grid is out of electric power Islanding operation is further classified into intentional islanding and unintentional islanding operations. In intentional islanding operation, the DG backs up critical loads while it separates from the main grid on islanding detection. Intentional islanding operation increases utilization of the DG system during the islanding operation. This paper proposes reasonal inverter topology and its control algorithm for seamless transfer of DG systems in intentional islanding operation.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.4
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• pp.431-436
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• 2023

In order to provide continuous Korea Augmentation Satellite System (KASS) services, the operation organization should continuously and systematically perform operations, maintenance, and technical activities. All subsystems of KASS, all Line Replacement Units (LRUs), and Software Replacement Units (SWRUs) should be operated and maintained continuously. In order to effectively manage these activities, it is necessary to develop an Operation Management Tool (OMT). For this purpose, operation management, operation organization, and operation activities were defined. The defined requirements were divided into general, function, interface, and database for OMT development, and functions and decision-making procedures consisting of site/asset/trouble/work order/schedule management were designed. The OMT developed by reflecting the site and asset information as well as the design content met predefined requirements. The OMT will be actively used in actual KASS operation and will evolve by continuously reflecting the additional requirements of operators. Through this tool, KASS will support continuous service provision.

• Journal of Korea Water Resources Association
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• v.40 no.2 s.175
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• pp.101-112
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• 2007

In this study, a methodology was developed to evaluate the effects produced in the event of joint-operation of dams from the viewpoint of water use. It was applied to evaluating the actual results of dam operation in the Han River basin. In order to evaluate the effects of real joint-operation in terms of water supply and flow conditions, the methodology used the satisfaction rate of water requirement and the stability of flow conditions at the evaluation site as indicator. In order to evaluate the effects of joint-operation in terms of power generation, the total power generation produced by dams was used as evaluation indicator. Actual operation results were evaluated by comparison of evaluation indicators relating to single dam operation by which the notified mont of water was supplied, as well as to optimization models. Results of actual joint-operation of the Han River basin, from 2001 to 2004, were compared yearly with results from single operation and optimization model; in terms of water supply, the satisfaction ratio of water requirement stood at $94.36{\sim}99.68%$ for single operation, $97.16{\sim}99.90%$ for actual joint-operation, and 100.0 % for optimization model for all four years. The stability of flow condition was evaluated by the coefficient of river regime and coefficient of flow conditions definitely, indicating that flow conditions were more stable in case of actual operation and optimization models than in case of single operation. The actual total power generation was compared with that generated by other operation rules, indicating that the optimization model increased the power generation by $-3.47{\sim}6.54%$ compared with the actual total power generation, and that the single operation decreased the power generation amount by $12.68{\sim}38.94%$ compared with the actual total power generation.

• Journal of Chest Surgery
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• v.22 no.4
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• pp.562-572
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• 1989

The changes of serum glutamic oxaloacetic transaminase [SGOT], serum glutamic pyruvic transaminase [SGPT], serum lactic dehydrogenase [LDH] and serum creatine phosphokinase [CPK] were examined during and after the open heart surgery. In the total of 52 patients with heart diseases including 40 cases of congenital heart anomalies and 12 cases of acquired valvular heart diseases who undergone open heart surgery under cardiopulmonary bypass. The results obtained are as follows: 1. The average value of SGOT before surgery was 30.27 [ 18:86 units. The enzyme was reached to the maximum of 139.88 [ 89.43 units on the 1st day after the operation [p< 0.05], the enzyme activity was gradually decreased from the 3rd day after the operation, returned to the normal range on the 7th day after the operation. 2. The average value of SGPT before surgery was 14.36 [ 7.45 units. The enzyme was reached to the maximum of 34.67 [ 27.64 units on the 2nd day after the operation, but it was valueless statistically, the enzyme activity was gradually decreased from the 3rd day after the operation, returned to the normal range on the 5th day after the operation. 3. The average value of LDH before surgery was 263.07 * 86.66 units. The enzyme was reached to the maximum of 662.29 * 303.60 units on the 2nd day after the operation [p < 0.05], the enzyme activity was gradually decreased from the 5th day after the operation, returned to the normal range on the 7th day after the operation. 4. The average value of CPK before surgery was 141.35 * 43.44 units. The enzyme was reached to the maximum of 377.42 [ 222.02 units on the 1st day after the operation [p < 0.05], the enzyme activity was gradually decreased from the 5th day after the operation, returned to the normal range on the 7th day after the operation. 5. In the relationships of the serum enzymes and duration of the extracorporeal circulation, the values on the group over 90 minute of the extracorporeal circulation were increased than on the group below 90 minute of the extracorporeal circulation, but it was valueless statistically.

• Special Issue of the Society of Naval Architects of Korea
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• 2009.09a
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• pp.97-106
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• 2009

Many production methods are tried to enhance the productivity efficiency. Parallel connected floating cranes are one of the examples to lift mega-blocks quickly and efficiently. However, a general operation manual to operate parallel connected floating cranes and a method to consider risks during lifting operation are not confirmed. And if each floating crane is operated by itself, it is very hard to cooperate. Therefore, Synchronized operation system is installed to control parallel connected floating cranes simultaneously and to be informed of each floating cranes data. And weighting factor is calculated by considering all hazards during the operation and the general operation manual is confirmed based on the factor. This paper introduces the procedure for lifting operations by parallel Connected Floating Cranes using synchronized operation system, and its applications to lifting operation of a heavy cargo such as barge lifting test, floating dock installation and 900 ton goliath crane replacement operation, etc.