• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3949-3956
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• 2022

Kori Unit 1 is planning a system decontamination project to reduce radiation exposure of decommissioning workers, prevent the spread of contamination and down-grade the level of classification of radioactive waste. The system decontamination range for Kori Unit 1 will be the entire primary system, including RCS, CVCS and RHRS. Some system design modifications are required for the system decontamination operation. In this paper, major system design modifications were evaluated based on the conditions that system restoration is needed after completion of system decontamination. The major system design modifications are CIDF connection location to system, system decontamination operating pressure control, RCP seal water injection and formation of letdown flow. It was evaluated that there was no negative effect on the system due to the system design modifications. However, as the RCP seal water is injected into the system in the oxidation process, the concentration of the oxidizing agent is diluted. Therefore, the oxidizing agent injection and system decontamination operation procedures should be developed to address the dilution effect of the oxidizing agent. The system design modifications dealt in this paper will be finally confirmed through on-site investigation in the future, and if necessary, the system design modifications will be re-evaluated.

• The KSFM Journal of Fluid Machinery
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• v.13 no.3
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• pp.24-29
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• 2010

Axial fans for an air-conditioning unit are designed to equip the system with an expected flow-rate and low noise level by applying the blade design method of multi-sectioning and local camber generation. In this study, the distributions of chord length, stagger angle, and camber angle are globally and locally determined for the given specific speed, which is considered to be relatively high. The mock-up fans are observed to satisfy the aerodynamic performance and the noise level for the system simultaneously and discussed in terms of local flow patterns related to the emitted noise.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.04b
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• pp.439-448
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• 2000

A multi-level design synthesis (MLDA) algorithm for efficiently optimizing orthotropic steel deck bridges is proposed in the paper, because it is usually very difficult to optimize orthotropic steel deck bridges using a conventional single-level (CSL) algorithn since the bridges have a large number of members and show complex structural behaviors. In the proposed MLDS algorithms a coordination method is introduced to divide the bridges into main girders and orthotropic steel decks and decomposition method is also used to reduce the number of design variables of the decks for system level optimization. For efficient optimization of the bridges the MLDS algorithm incorporates the crucial approximation techliques such as constraints deletion and stress reanalysis. The constraint deletion technique for deflection is found to be very useful for the optimization problem of the bridges, since a deflection constraint is usually inactive in the design. Considering the complex system of the bridges, the proposed the efficient stress reanalysis technique may prove to be a very effective method, since it does not require expensive design sensitivity analyses. The applicability and robustness of the MLDS algorithm is demonstrated using various numerical examples and compared with other algorithm presently available so far.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1183_1184
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• 2009

The synchronized visual message system device of level crossing provides warning system with the use of developed corresponding technology when the train is approaching forward to limited distance in level crossing. To ensure of safety driving for coming transit from road, it detect the location and velocity of train and transport the information to wayside warning device to prevent the collision with train. This paper is about the detailed design of synchronize VMS for passing transit at the level crossing and develop the physical contents of level crossing VMS with expression words, operational device, massage transportation algorism which are based on the proto type study of communication method and information contents for level crossing VMS.

• The Journal of Sustainable Design and Educational Environment Research
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• v.10 no.2
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• pp.61-72
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• 2011

The purpose of this study is to carry out the research of the satisfaction level of consumers (students and teachers) and managerial characteristics for model classes of the subject classroom system and to draw the effective plan of the system. The conclusions are as follows First, the biggest advantage of the system is to fulfill the educational goal according to an individual level and ability of each student while the biggest disadvantage is the inconvenience of students to change their classrooms for each specific class. Second, it is necessary to rearrange the classrooms according to the applied subjects from the aspect of curriculum management since the time frame is not convenient for recess. English and mathematics are required preferentially as applied subjects, however Korean (as a national language) and science are needed to be taught with level-differentiated classes, too. The ideal size of classes is most likely 20-25 students according to the result of research. Lastly, the space of environment is another requirement to secure smooth flow of students' movements and extra space for technical devices used for information research. The above analysis indicates the necessity of supplementation in space planning for further implementation of subject classroom system in secondary school.

• Journal of The Korea Institute of Healthcare Architecture
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• v.17 no.1
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• pp.23-32
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• 2011

Recently, with the advent of high risk infectious agent such as the Ebola virus, SARS, special research facilities dealing with such dangerous pathogenic are drawing attention gradually. Especially, this kind of facilities can be called BL4(Biosafety Level 4) facility. At the moment, Korean government is going to construct BL4 institute in order to handle efficiently such kind of pathogen. However, there are no proper design guidelines for BL4 facility. This paper proposes circulation system of BL4 facility on the basis of analysis of existing BL4 guidelines of Canada, and Korean BL3 facilities. The outcomes of this study are as follows. At first, functional areas of BL4 facilities have been divided into three categories according to the hazard level ; dangerous area, transitional area, and ordinary area. Secondly, circulation system of BL4 facility has been explored as a form of diagram according to the circulating subjects. These include human, laboratory animals, hazardous pathogen, equipments and cloth. This study has some limitations in that it lacks empirical evidences and concrete SOPs(Standard Operating Procedure). Despite of some weaknesses, it is expected to give some preliminary guidelines for the design of circulation system in BL4 facilities.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1133-1136
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• 2003

This paper has been studied about the implemention of the data-encription processor and imformation security system. Also in the paper, the brief contents of the verification of the data-encryption algorithm and the method of using HDL-level sources implemented is described. And then this paper has been designed for multi-level data secure system to verify and analyze the data-encryption processor implemented as VHDL.

• Journal of the Microelectronics and Packaging Society
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• v.9 no.1
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• pp.43-48
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• 2002

Semiconductor chip encapsulation process is employed to protect the chip and to achieve optimal performance of the chip. Expert decision-making to obtain the appropriate package design or process conditions with high yields and high productivity is quite difficult. In this paper, an expert system for semiconductor chip encapsulation has been constructed which combines a knowledge-based system with CAE software.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.12
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• pp.163-170
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• 2002

The quality of a precision product, in general, relies on the accuracy and precision of its manufacturing and inspection process. In many cases, the level of precision in the manufacturing and inspection system is also dependent on the positioning capability of tool with respect to the work piece in the process. Recently the positioning accuracy level has reached to the level of submicron and long range of motion is required. For example, for 1 GDARM lithography, 20nm accuracy and 300mm stroke needs. This paper refers to the lithography stage especially to fine stage. In this study, for long stroke and high accuracy, the dual servo system is proposed. For the coarse actuator, LDM (Linear DC Motor) is used and for fine one VCM is used. In this study, we propose the new structure of VCM for the fine actuator. It is 3 axis precision positioning stage for an aligner system. After we perform the optimal design of the stage to obtain the maximum force, which is related to the acceleration of the stage to accomplish throughput of product. And we controlled this fine stage with TDC. So we obtained 50nm resolution. So later more works will be done to obtain better accuracy.

• Journal of the Korean Operations Research and Management Science Society
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• v.29 no.4
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• pp.61-72
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• 2004

In this paper, we design sampling inspections and service capacities simultaneously for multi-products. Particularly, we extend Kim(2003) by introducing the fixed cost of providing services. We show that, due to the fixed cost considered, the cost function of a product is no longer linear or convex in terms of the level of service provision, and the total inspection is prefered to the small level of service capacity which results in high burden of the fixed cost. And we develop a simple framework to deal with this joint design problem for a product. Also we consider the problem of allocating the given number of the total service capacities among products. A dynamic programming algorithm is developed to determine the optimal allocation which minimizes the overall total cost of the system and the optimal allocation can be obtained with the considerably smaller computations than the total number of possible allocations. The results can be used to support planning decisions and to aid the joint design of inspections and service capacities for products.