• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.535-536
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• 2011

This paper studies the validity about a joint operation of neutral wire and overhead grounding wire in combined distribution systems. The overhead grounding wire and neutral wire are currently installed separately and grounded by common. However there is no any ineffectiveness or electrical problem in case of the proposed system, such system can be operated at real distribution system. Therefore this paper describes the suitability of a joint operation through lightning surge analysis on combined distribution systems and analyzes the optimal position of lightning arrester on joint operation of neutral wire and overhead grounding wire. Lightning surge analysis is carried out by EMTP/ATPDraw to obtain the overvoltage of overhead line and underground cable in various conditions such as location and current types of lightning stroke. Over voltage gained by the analysis show that the insulation strength of the joint operation case is not stable compare with the current operation case.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.31-39
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• 2007

In this study we developed a turbidity management system to support the operation for effective turbid water management. The decision-making system includes various models for prediction of turbid water inflow, effective reservoir operation using the selective withdrawal facility, analysis of turbid water discharge in the downstream. The system is supported by the intensive monitoring devices installed in the upstream rivers, reservoirs, and downstream rivers. SWAT and HSPF models were constructed to predict turbid water flows in the Imha and Andong catchments. CE-QUAL-W2 models were constructed for turbid water behavior prediction, and various analyses were conducted to examine the effects of the selective withdrawal operation for efficient high turbid water discharge, turbid water distribution under differing amount and locations of turbid water discharge. A 1-dimensional dynamic water quality model was built using Ko-Riv1 for simulation of turbidity propagation in the downstream of the reservoirs, and 2-dimensional models were developed to investigate the mixing phenomena of two waters discharged from the Andong and Imha reservoirs with different temperature and turbidity conditions during joint dam operation for reducing the impacts of turbid water.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.07a
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• pp.57-68
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• 2004

A demonstrative operation of a membrane system with its caparity of 3,600m$^3$/d was carried out using reservoir water as raw water for the application of membrane filtration system to drinking water treatment. The operation was undertaken at a constant flux of 0.9 m$^3$/m$^2$/d for three months. Backwashing with NaClO of 3 ppm was allowed for 30 seconds every 20 minutes of filtration. Physical cleaning was introduced after 69 times of filtration/backwashing cycle with air-scrubbing and backwashing for 1 minute, and flushing for 2 minutes. In this study, water treatment performance was investigated compared with the existing rapid sand filtration process. The membrane system was operated with no significant problems during the test period. Higher water quality was obtained in the membrane filtration than in the rapid sand filtration in terms of particulate matters such as turbidity and microbes. Although the finished water of the membrane filtration contained slightly higher concentration in dissolved matters than that of the conventional one, it met the drinking water standard. The demonstrative operation showed that membrane filtration has a reliability in drinking water treatment. Researches should be needed on cost analysis through long-term operation and optimization of operation condition for further application.

• Journal of Korean Port Research
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• v.13 no.2
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• pp.189-198
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• 1999

The purpose of this paper is to develop a knowledge-based real-time decision support system to support decision makers for efficient berth operation of Inchon Port. In these days the berth operation problems have been many studied. The berth operation rules differ from port to port and the problem is highly dependent on natural geographical and operational environment of port. In Inchon Port the ship’s entrance into port and departure from port is extremely affected status of dock. In this paper we analyzed some effects of dock a specific character of Inchon Port with a real data of ship’s in Inchon Port. And reconstruct a previous expert’s knowledge of berth allocating problem in Inchon Port. Also the mechanism for the efficient berth operation has been studied by repeatedly dispatching in order to obtain a best effect of berth allocation, with real-time updated information for delay at service time of a specific berth and changing of a working-berth. The system is developed with graphic user interface(GUI) concept using user interactive approach. And this system will be provide decision support maker with an efficient and fast way to berth allocating and reduce wastes of time space and manpower in Inchon Port operation.

• Nuclear Engineering and Technology
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• v.28 no.3
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• pp.257-264
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• 1996

The conventional Equipment Environment Qualification (EEQ) envelope is developed based on the containment responses during the design basis events. The Safety Depressurization System (SDS) design without In-containment Refueling Water Storage Tank (IRWST) adopted in the Ulchin 3&4 challenges the conventional EEQ envelope during long term Feed and Bleed (F&B) operation due to the direct discharge of high mass and energy into the containment. Therefore, it is necessary to confirm that the containment pressure and temperature history during the long term F&B operation does not violate the conventional EEQ envelope. However, this subject has never been quantitatively assessed before. To investigate the success path of long term F&B operation this paper analyzes the thermal hydraulic response of the containment and Reactor Coolant System (RCS) until the completion of depressurization and cooldown of RCS into Shutdown Cooling System (SCS) entry condition. It is found that the SCS entry condition can be reached within 6 hours without violating the EEQ curve by proper operation of SDS valves, High Pressure Safety Injection (HPSI) pumps and active Containment Heat Removal System (CHRS). The suggested strategy not only demonstrates the feasibility of long term F&B operation but also can be utilized in the preparation of Emergency Procedure Guidelines (EPGs)

• The Journal of Korea Robotics Society
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• v.15 no.1
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• pp.39-47
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• 2020

This paper presents a control and operation system for a remotely operated vehicle (ROV). The ROV used in the study was equipped with a manipulator and is being developed for underwater exploration and autonomous underwater working. Precision position and attitude control ability is essential for underwater operation using a manipulator. For propulsion, the ROV is equipped with eight thrusters, the number of those are more than six degrees-of-freedom. Four of them are in charge of surge, sway, and yaw motion, and the other four are responsible for heave, roll, and pitch motion. Therefore, it is more efficient to integrate the management of the thrusters rather than control them individually. In this paper, a thrust allocation method for thruster management is presented, and the design of a feedback controller using sensor data is described. The software for the ROV operation consists of a robot operating system that can efficiently process data between multiple hardware platforms. Through experimental analysis, the validity of the control system performance was verified.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.181-187
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• 2011

Since 2003, state transportation study core technology development is being promoted as part of the bimodal trams operating in accordance with the development of refractive vehicle as research infrastructure for building high-tech road transport system has been the research and development. Bimodal trams of refraction as the vehicle for him to introduce domestic first ever operation management system also developed in Korea according to case-based technology system, but most of the country, and, in this study, mainly those based on technology integration building management system and the bimodal trams of refraction of a vehicle operated was to highlight the features and benefits. Bimodal tram station itself is the way the exclusive properties and to operate the route with large transport capacity has the characteristics of the railway, but the only routes such as railroad lines is not of closed roads under certain circumstances, the flexibility to use has to be integrated operations management system of bimodal trams characteristics of the railroads and public transportation by combining the characteristics of a flexible, convenient and secure services to users with the aim of providing research and will denote the system developed. In this study, bimodal integration system required for the operation of the tram station around the wired and wireless network management center, applying the organic integration into one system so that you have to be centrally managed. In addition, the existing traffic management system operates as a unidirectional rather than monitoring all system-wide management via the interactive network through real-time requests and responses were configured to allow management and control. These findings of the existing traffic operation management system that you can jump step can be based on future unmanned vehicles and related systems through control of the operation management system will be offered as a basis.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.26-32
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• 2008

Middle Route Project, the largest water conveyance system in China delivers the water of Changjiang River to North China. In order to create canal operation simulation system, mathematical models are established based on the analysis of hydraulics about steady flow, unsteady flow, and check gate. By simulating the canal operation behavior, we improved the check gate control algorithm and predicted the change process of water surface and flow profile which is very valuable to actual canal operation.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.896-898
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• 1996

This paper presents the optimal operation scheduling of the private cogeneration system connected with auxiliary equipments. And the optimal size of auxiliary equipments is determined through evaluations of the minimum operation cost. The optimal operation scheduling is established by using the linear programming method. Simulation results show that the auxiliary boiler is operated as an economical facility but the thermal storage tank is used as a back up facility for emergency.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.24-26
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• 1994

This paper describes a numerical model for the short-term operation strategy of the cogeneration systems. Especially this paper considered various auxiliary equipments used for the effective operation of cogeneration system. Minimum daily operation costs of topping cycle are calculated by using LP. Simulation results of some cases are analyzed and compared each other. Through these simulations the validity of the proposed model considered various auxiliary equipments is verified.