• Korea-Australia Rheology Journal
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• v.15 no.4
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• pp.167-171
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• 2003

The backlight unit (BLU) is used as a light source of TFT liquid-crystalline-display (TFT-LCD) module. In this backlight unit, one of important components is the light guide, which is usually made of transparent polymers. Currently, the screen-printing method is mainly used for the light guide as a manufacturing process. However, it has limitation to the flexibility of three-dimensional optical design. In the present paper a new alternative manufacturing method for the light guide with low-cost is proposed. This manufacturing method is named as direct surface forming (DSF), which is very similar to the well-known hot embossing except for partial contact between mold and substrate. The results of this new manufacturing method are presented in terms of processing condition, dimensional accuracy, productivity, etc.

• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.55-59
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• 2002

Delamination means that cracking occurs on the interface layer between composite laminates. In this paper, to predict the delamination growth in composite laminates subjected to low-velocity impact, the unit load method was introduced, and an eighteen-node 3-D finite element analysis, based on assumed strain mixed formulation, was conducted. Strain energy release rate, necessary to determine the delamination growth, was calculated by using the virtual crack closure technique. The unit load method saves the computation time more than the re-meshing method. The virtual crack closure technique enables the strain energy release rate to be easily calculated, because information of the singular stress field near the crack tip is not required. Hence, the delamination growth in composite laminates that are subjected to low-velocity impact can be efficiently predicted using the above-mentioned methods.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.121-124
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• 2001

This paper proposed resource allocation algorithm for the minimum switching activity of functional unit in high level synthesis process as like DSP which is circuit to give many functional unit. The resource allocation method after scheduling use the power function calculating average hamming distance and switching activity of the between two input. First of all, the switching activity is calculated by the input value after calculating the average hamming distance between operation. In this paper, the proposed method though high If level simulation find switching activity in circuit each functional unit exchange for binary sequence length and value bit are logic one value. To use the switching activity find the allocation with minimal power consumption, the proposed method visits all control steps one by one and determines the allocation with minimal power consumption at each control step. As the existing method, the execution time can be fast according to use the number of operator and max control step. And it is the reduction effect from 6% to 8%.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.208-213
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• 2008

In order to assess the reliability of the electronics control unit for vehicles, accelerated life test model and procedure are developed. By using this method, failure mechanism and life distribution are analyzed. The main results are as follows : i) the main failure mechanism is degradation failure that is, junction destruction of a semiconductor resin by high temperature. ii) the life distribution of the electronics control unit for vehicles is fitted well to Weibull life distribution and the accelerated life model of that is fitted well to Arrhenius model. iii) at the result of the life distribution, accelerated life test method is developed, and test time for life assessment will be shortened by 5,000 hours by this test method.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.311-314
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• 2001

This paper describes the optimizing method of direct load control (DLC) considering unit commitment which is based on dynamic programming. To solve DLC problem considering unit commitment, 3-dimensional dynamic programming as a new unit commitment method is developed. And, energy payback is concerned for DLC. As a result, optimization of operating schedule with DLC is possible. This method is applied to the test system, and usefulness of the method is verified.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.105-106
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• 2006

It is important to identify the exact target optical cable that a worker look for when he executes a cable construction work. Until now, An Optical cable identification work has been done by a manual pulling of an optical cable or by the method of using RF signals. But these methods not only consume much time and labor costs but also have a distance limit of the optical cable to identify. In this paper, we propose a method that uses the phase change signal of the optical interferometer to identify an optical cable. With the proposed method the field worker can have an efficient tool to prevent miscutting the optical cable and can also save operating costs.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.2
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• pp.70-77
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• 2000

This paper proposes a method of solving a unit commitment problem using tabu search (TS) which is heuristic algorithm. Ts is a local search method that starts from any initial solution and attempts to determine a better solution using memory structures. In this paper, to reduce the computation time for finding the optimal solution, changing tabu list size as intensification strategy and path relinking method as diversification strategy are proposed. To show the usefulness of the proposed method, we simulated for 10 units system and 110 units system. Numerical results show improvements in the generation costs and the computation time compared with priority list, genetic algorithm(GA), and hybrid GA.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.220-221
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• 2013

Exterior walls are designed and constructed through design focused exterior wall system. Nowadays, freeform facade design has been changing according to material, form and function of the exterior wall system. Especially, curtain wall facade system is designed and manufactured using solar shading faces. However, the traditional method have a lot of difficulties in the currently performing technology for curtain wall facade. It is important to make the freeform facade components that integrated as a surface of freeform buildings. Therefore it is necessary to develop unit module construction method for freeform facade.

• KIEE International Transactions on Power Engineering
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• v.5A no.1
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• pp.16-21
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• 2005

In this study, a new Unit Commitment (UC) algorithm is proposed to consider the uncertainty of a daily load profile. The proposed algorithm calculates the UC results with a lower load level than that generated by the conventional load forecast method and the greater hourly reserve allocation. In case of the worst load forecast, the deviation of the conventional UC solution can be overcome with the proposed method. The proposed method is tested with sample systems, which indicates that the new UC algorithm yields a completely feasible solution even when the worst load forecast is applied. Also, the effects of the uncertain hourly load demand are statistically analyzed, particularly by the consideration of the average over generation and the average under generation. Finally, it is shown that independent power producers participating in electricity spot-markets can establish bidding strategies by means of the statistical analysis. Therefore, it is expected that the proposed method can be used as the basic guideline for establishing bidding strategies under the deregulation power pool.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.7
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• pp.673-682
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• 2004

The cost accounting of products on energy system is important for evaluating the economical efficiency and deciding the reasonable sale price. In the present, the suggested OECOPC method was applied to a combined cycle cogeneration, and each unit cost of electricity and heat products was calculated. In addition, the previous thermoeconomic methods were applied and calculated to equal system. As a result of comparing various methods, the unit costs by OECOPC method were calculated in the middle value of those. This result tells that OECOPC methods are most moderate. The suggested OECOPC method can apply any energy system. Hence this method is expected to make contribution to cost accounting on energy System.