• Journal of Korea Water Resources Association
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• v.31 no.1
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• pp.105-113
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• 1998

Reservoir operation during flood period can be divided into two parts: One is for an operating policy during flood period to consider water conservation and flood control, and the other is for flood time on a random water level at flood forecasting, This study is concerned with reservoir operation and discusses general reservoir operation at flood time. Flood control has problems such as the uncertainty of hydrologic models. technical limitations and some constraints. Therefore, we may prepare the quantitative flood control methods based on the assured flood control storage for reservoir operation. Transformed Reservoir Flood(TRF) Reservoir Operation Method(ROM) is a procedure which determines the adequate releases with considering dam safety for flood inflows over non-damaging discharge. Based on the TRF ROM which was explained in our published paper. the study discusses the TRF ROM with additional investigations and the general reservoir operation rules at flood time.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.1
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• pp.91-101
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• 2003

Boryeong Seadike located at southwestern seashore of Korean peninsula completed in 1997. Sluice gate operation can be an important factor to maintain lake water quality and reduce retaining time of pollutants within lake. The lake water quality simulation model, WASPS was adopted and tested to find out proper gate operation timing and discharge amount. From the simulation of sluice gate operation, the results showed that the later the time of discharge for loosing 1 day successively to 6 days, the better the quality of water. Discharge amount showed relatively minor changes of water quality. This means that pollutants flowed into lake from watershed do not have enough time to mix up with deep water when the gate opened at early time. About 3 days delay of discharge caused the dilution effect to stabilize the lake water quality in case of Boryeong freshwater lake.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1134-1139
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• 2009

Haul routes for earthmoving operation need to be carefully selected because the decision on the haul routes could make a significant difference in the project's cost and time. This paper proposes a decision support system for improving productivity of earthmoving operation that helps construction managers choose the best haul routes of trucks based on time slots. Also, a methodology for optimal selection of haul routes considering traffic conditions and topographic conditions of the routes is explained. Raster data model is used to find an available shortest path based on cost weighted distance. A system was developed on a geographic information system environment for efficient database management and easy manipulation of graphical data. A real-world case study was conducted to verify the applicability of the proposed system.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1871-1877
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• 2009

KORAIL has been established by 1st January 2005. From organization change to KORAIL(Korea railroad Corporation), labour union and company management team has been argument for their train crews and drivers operation system. For example, train crew and driver working conditions; working hours per week, off day and duty day time, over night time working payment, current position payment, preparation time, company own lodge operation and so on. I assure that this comparison study for train crew and driver operation between KORAIL and EWS will helps to improve other korean railway companies management efficiency. In conclusion, EWS has 4$\sim$6 times more efficient employee for active operation than KORAIL per 1 freight brock-train operation. EWS has very resonable train crews and driver operation system, and self-control regulation for employee and management team with trusty. This thesis propose that korean railway companies and their own labour unions need joint research and benchmarking other oversea railway companies as like EWS.

• Korean Journal of Materials Research
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• v.15 no.7
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• pp.465-472
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• 2005

Preparation of copper film on PET substrate was carried out by cyclic operation of RF-magnetron­sputtering under continuous operation of ECR-CVD. The purpose of this study is aimed to an increase in deposition rate with keeping excellent adhesion between copper film and PET. In order to optimize the sputtering time under continuous ECR-CVD, cyclic operation concept is employed. By changing parameters of cyclic operation such as split of e and cycle time of A, the characteristics and thickness of the deposited copper film are controlled. As $\theta$ value increase, film thickness could confirm to increase and its surface resistivity value decreases. The highest adhesive strength appears at $\theta=0.33$ and cycle time of 30 min. The uniformity of copper film shows $5\%$ in our experimental range.

• Journal of the Institute of Convergence Signal Processing
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• v.10 no.4
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• pp.280-288
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• 2009

In this paper, we developed new time information recording module of VSI (VLBI Standard Interface) format by analyzing the Mark5B recorder control and operation software with 1Gbps speed, which is able to record the weak signal of space radio source, through the Korean VLBI Network (KVN). The control and operation software of high-speed recorder consists of 2 kinds of software, which is that it can operate RAID control board by controlling large capacity HDD drive and the network control and operation. Especially, core software in high-speed recorder is able to output the results after performing and analyzing the input command. Through the analysis of control and operation software, new time information recording module, which is needed to process the observed data for correlation, is developed. New developed time information recording module can record the time information together after checking the interrupt of 1PPS(Pulse Per Second) input signal when the observed data will be recorded. To verify the normal operation of the developed time information recording module, we performed the real observation test and confirmed the effectiveness of developed software through analyzing the recorded observation data.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.196-197
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• 2014

Low carbon construction is an important operation management goal such as cost, time, and quality in construction community. This paper introduces a system which measures the variability of carbon dioxide amounts. First, this system allows creating construction operation models of which the level of detail is breakdown into the work task level. Second, the system implements sensitivity analysis along with a ranges of resources that are allocated in an operation model. It facilitates to find the optimal resource combination using the operation performances such as the amount of emissions, operation completion time, and cost. Lastly, it identifies the best fit probability distribution functions of performance criteria given a certain resource combination. It allows project manager to query the percentages to complete the operation within a limitation specified by the system users.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.1
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• pp.199-202
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• 2009

Scan design is currently the most widely used structured Design For Testability approach. In scan design, all storage elements are replaced with scan cells, which are then configured as one or more shift registers(also called scan chains) during the shift operation. As a result, all inputs to the combinational logic, including those driven by scan cells, can be controlled and all outputs from the combinational logic, including those driving scan cells, can be observed. The scan inserted design, called scan design, is operated in three modes: normal mode, shift mode, and capture mode. Circuit operations with associated clock cycles conducted in these three modes are referred to as normal operation, shift operation, and capture operation, respectively. In spite of these, scan design methodology has defects. They are power dissipation problem and test time during test application. We propose a new methodology about scan shift clock operation and present low power scan design and short test time.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.46
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• pp.137-146
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• 1998

Most studies related to AS/RS are about operation policies or system designs. However, the studies on operation policy could not deal with various products using the single unit load system. In this paper, two different sized units are introduced and six different AS/RS operation policies are developed to process the different sized items. Computer simulation is used to evaluate AS/RS performances on various operation policies and to find the most effective operation policy for each case. The simulation model is developed using GPSS/PC and operation policies include COL-FIFO-SP, SIL-FIFO-SP, COL-RN-SP, COL-FIFO-LP, SIL-FIFO-LP and COL-RN-LP. The policies are evaluated based on the criteria of crane utilization, rack utilization, crane moving time, throughput and waiting time.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.310-313
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• 1996

Mathematical programming method for finding optimal solution of job shop scheduling is inadequate to real situation because fo too much computation time. In contrast, dispatching rule is helpful for reducing compuation time but is not guaranted to find optimal solution. The purpose of this paper is to develop a new dispatching rule and procedure to minimize mean flow time whose result is near the optimal solution for job shop scheduling. First step is to select machine which have shortest finishing operation time among the schedulable operations. Second step is to select operation with regard to estimated remaining operation time. The suggested rule is compared with nondelay and MWKR rule for three examples, and is confirmed to be most effective to minimize mean flow time.