• 품질경영학회지
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• 제13권2호
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• pp.66-72
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• 1985

The objective of mixture experiments with process variables is to find experimental blends and conditions that produce the product of highest quality. In this paper, designs for mixture experiments with process variables are presented, where the emphasis is on using only a fraction of the total number of possible design points and the fitting of reduced models for measuring the effects of the mixture components and process variables.

• 한국기계가공학회지
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• 제7권3호
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• pp.36-40
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• 2008

This study is analyzed by the simulation of automotive steering system. The maximum equivalent stress of $2.2418{\times}109Pa$ and the maximum total displacement of 0.014929m are shown at the universal joint and its lower part respectively. As the minimum cycle of 34.047 is shown at the universal joint in case of fatigue analysis, it is possible to have greatest damage at this part. In case of natural frequency analysis at vibration, its frequency of 47 to 59Hz is occurred generally. The maximum total displacement of 0.5m is shown at handle on the natural frequency of 57 to 58Hz. And the displacement over 2m is shown at the lower part of universal joint on the natural frequency of 58 to 59Hz. As the basis of the simulation analysis of steering system, passenger's comfort of car body can be improved in the design of practical part and the design effect necessary to safe driving can be promoted.

• 산업경영시스템학회지
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• 제23권57호
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• pp.93-102
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• 2000

The objective of this paper is to introduce to development of resource planning system of footwear manufacturing. The system development is to be done separately by module and each of which makes interface possible. And the final goal of the system development is to combine those modules to be ERP system covering all works from order to make, shipment, accounting. First, in this case study, introduce analysis of existing business flow and design of standard business process for development of systems. Second, describe in and out of the standard business process for shoes production and information management. Third, basic structure and design of the total system flow, configuration of completed 6 sub-systems of developing total 13 sub-system are presented. Fourth, function of software modules and principal algorithm and basic data structuring techniques o the 6 sub-systems are explained. Finally, hereafter implementation and development plans are presented.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.823-830
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• 2022

The risk of project execution increases due to the enlargement and complexity of Engineering, Procurement, and Construction (EPC) plant projects. In the fourth industrial revolution era, there is an increasing need to utilize a large amount of data generated during project execution. The design is a key element for the success of the EPC plant project. Although the design cost is about 5% of the total EPC project cost, it is a critical process that affects the entire subsequent process, such as construction, installation, and operation & maintenance (O&M). This study aims to develop a system using machine-learning (ML) techniques to predict risks and support decision-making based on big data generated in an EPC project's design and construction stages. As a result, three main modules were developed: (M1) the design cost estimation module, (M2) the design error check module, and (M3) the change order forecasting module. M1 estimated design cost based on project data such as contract amount, construction period, total design cost, and man-hour (M/H). M2 and M3 are applications for predicting the severity of schedule delay and cost over-run due to design errors and change orders through unstructured text data extracted from engineering documents. A validation test was performed through a case study to verify the model applied to each module. It is expected to improve the risk response capability of EPC contractors in the design and construction stage through this study.

• International Journal of Quality Innovation
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• 제8권2호
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• pp.115-131
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• 2007

The vehicle development process (VDP) is iterative in nature with numerous interactions and information flows between design groups and between development phases. The VDP has been changed from a sequential-functional development to a concurrent-team based approach. Concurrent execution of design activities may reduce the development lead-time, but it increases the managerial complexity in the VDP. A system dynamics model was developed to understand the transient behavior of parallel, overlap, and sequential processes in the VDP and to determine the optimal level of overlapping considering the development lead-time and total number of reworks. The simulation results showed that different execution processes should be used, depending upon the intensity of reworks.

• 한국경영과학회지
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• 제23권3호
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• pp.123-133
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• 1998

A cell design model based on operation sequence is proposed for maximizing the total parts flow within cells considering the data of Process plans for parts, Production volume, and cell size. A relationship between machines is calculated on the basis of the process plans for parts obtained from process plan sheets. Then the machines are classified into machine cells using the relationship. The model is formulated as a 0-1 integer programming and a genetic algorithm approach is developed to solve the model. The developed approach is tested and Proved using actual industrial data. Experimental results indicate that the approach is appropriate for large-size cell design problems efficiently.

• 한국CDE학회논문집
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• 제12권6호
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• pp.452-460
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• 2007

To achieve rapid developments and cost savings in manufacturing industries including automotive die shops, new paradigm and its supporting systems of information managements through total product life cycle are needed for concurrent and collaborative engineering. For manufacturing of automotive press dies, integrated and efficient managements of PPR information including product, manufacturing process and resource are essential. In this paper, we introduce a PLM approach to achieve engineering collaborations in product development and production of automotive dies. To prove concepts and benefits of PPR information managements, we implement new business workflow and detail procedures, PPR information management system and other related applications. By PPR information managements in PLM, improvements in quality of engineering results and savings in time from design to production of dies are possible.

• 수산해양교육연구
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• 제20권2호
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• pp.184-200
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• 2008

The purpose of this paper is to develop instructional activity support model for capstone design in order for improving creative engineering education. To do this, having extracted the core idea of capstone design, and elicited core learning activity process, and grasped core supportive factors according to each core learning activity process that elicited, an improved instructional design model for capstone design was then developed through formative evaluation with respect to the draft of the instructional system development model for capstone design. As to major research methods, case analysis, requirements analysis through interview, and formative evaluation by experts were employed, and then research studies were undertaken. The formative evaluation by experts was carried out for two hours in 2007, and the experts participated in the evaluation consisted of total 6 persons: two specialists of capstone design contents, two professionals in field works, and two expert instructional designers in education engineering. Interview results had been reflected in this research when developing final instructional design model for capstone design. The core learning activity process of the final instructional design model for caption design, which developed in this research, comprises following stages: (1) Team building $\rightarrow$ (2) Integrated meeting between industry and academy $\rightarrow$ (3) Analysis of tasks $\rightarrow$ (4) Clarification of tasks $\rightarrow$(5) Seeking solutions for issues $\rightarrow$ (6) Eliciting priority of solutions $\rightarrow$ (7) Designing solutions and construction $\rightarrow$ (8) Exhibiting outcomes and presentation $\rightarrow$(9) Gaining comprehensive insights Also, in the core learning activity process, supportive factors that support implementation of each step were presented having been categorized into facilitator (teacher, and professionals in field works), learner and tool, etc.

• 공업화학
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• 제29권4호
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• pp.446-451
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• 2018

플라보노이드성분 함량이 높은 밀싹을 이용하여 유효성분을 추출하고, 중심합성계획모델을 이용하여 추출공정을 최적화하였다. 중심합성계획모델의 반응치로는 추출수율과 플라보노이드성분 함량을 설정하고, 독립변수인 추출시간, 주정/초순수 부피비, 추출온도에 따른 주효과도와 교호효과도를 해석하였다. 추출수율의 경우 추출시간과 추출온도가 상대적으로 큰 영향을 미쳤으며, 플라보노이드성분 함량의 경우에는 추출시간의 영향이 가장 크게 나타났다. 추출수율과 플라보노이드성분 함량을 모두 고려한 결과 최적추출조건은 추출시간(2.44 h), 주정/초순수의 부피비(50.00 vol%), 추출온도($54.41^{\circ}C$)이었으며, 이때 추출수율은 30.14 wt%, 플라보노이드성분 함량은 $35.37{\mu}g\;QE/mL\;dw$이었다. 이 조건의 실제 실험결과 추출수율(29.92 wt%), 플라보노이드성분 함량($35.32{\mu}g\;QE/mL\;dw$)으로 오차율은 각각 0.39%, 0.74%이었다. 이는 두 개의 반응치를 동시에 분석하는 다중분석 종합분석임에도 높은 정확도를 나타낸 것으로 본 연구에서의 최적화과정 신뢰도가 우수한 것으로 사료된다.

• 한국경영과학회지
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• 제22권3호
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• pp.23-36
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• 1997

In the design of telecommunication network, the network configuration using hubbing topology is useful for designing and managing the network efficiently : i. e. all of central offices (COs) are grouped into clusters. Each cluster has one hub consisting of large-scale transmission facilities like digital cross-connect systems and ATMs. In clustering process, the community of interest and geographical factor should be considered. However, there exists a tradeoff between two factors. One is to minimize total link costs for geographical factor and the other is to maximize the total intra-cluster traffics for community of interest. Hence, this can be solved by multiobjective linear programming techniques. In this paper, the problem under considerations is formulated as two p-median subproblems taking into considerations total costs and total intra-traffics, respectively. Then we propose the algorithm to solve the problem based on the concept of cost-traffic tradeoff. The algorithm enables to identify efficient cost-traffic tradeoff pairs. An illustration is also presented.