• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.872-876
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• 2008

설계VE 프로세스 과정 중 기능분석을 성공적으로 수행하지 위해서는 VE대상의 선정이 중요하다. 그러나 설계VE활동시 대상선정 단계에서 설계VE 집중검토대상을 선정해야 하지만 그 활용성이 미비하였으며, 활용방법에 어려움이 따랐다. 이에 본 연구는 대상선정을 명확하게 하여 차후 기능분석에서 효과적으로 반영할 수 있는 방안으로 SWOT분석을 제안하고자 한다.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.88-95
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• 2001

To convert the construction industry from 'the high cost, the low efficiency' to 'the low cost, the high efficiency and value-added industry' and to enhance the performance and quality of products while reducing the cost, the related law and guideline were established and promulgated, which regulate that value engineering workshop during the preliminary design and the detail design stage should be a mandatory process. But VE practitioners are still confusing in choosing the proper value engineering process, because processes those are described in the various references use the different terms, steps and activities, even though they have their own specific characteristics. To resolve these confusions, the existing steps and activities of three kinds of the literature, four kinds of the organization's policy and other four kinds of study examples relating to the design VE were examined. And then, the differences and expecting problems were extracted through the comparison and analysis of those materials. After that, VE specialists' opinion through the questionnaire survey were grasped. Based on those studies the improved design VE Job Plan and activity statements were suggested.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.127-132
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• 2005

Despite all efforts, many product development projects fail and lead to an introduction of products that do not meet customers' expectations. In general, designers usually relies upon their past experiences of similar products as a source of design knowledge when they work on a new design project. Designers need a set of practical step-by-step tools and methods which ensure a understanding of customers' needs and requirements, as well as a past design experience knowledge. In this paper we propose a design initial value module for an excavator that proposes a key initial design parameter value in an early design stage to improve a design process on Customer Requirements. It makes possible to support designers more effectively, objectively, and easily. Also it can propose better products in terms of a customer satisfaction.

• Journal of the Korean Society of Safety
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• v.24 no.6
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• pp.79-85
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• 2009

This study presents an algorithm to select the best alternative plane among various bridge superstructure types(Steel box girder, Rational girder, PSC-I girder) using Value Engineering(VE). Economical efficiency, landscape, constructability, maintenance, stability, function of bridge superstructure were taken into consideration in the designing of bridge. Economical efficiency was evaluated for each alternative plan with optimal design considering Life Cycle Cost(LCC). Repair and rehabilitation histories and some factors were set to get reasonable results. In the application of Analytic Hierarchy Process(AHP), consistency of Pairwise Comparisons Matrix was evaluated and the best plan was determined.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.1
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• pp.151-158
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• 2003

Design changes frequently occur while design activities are performed. If the impact of design changes is estimated, design efficiency can be improved. But, the types of design changes are various and they can affect other design parts. Hence, it is difficult to deal with design changes directly. The purpose of this research is to develop systematic algorithms for change propagation tracing and change impact analysis, and then to implement a change impact analysis system. We have selected a process-based design and a design environment which is composed of design parameters and constraints. The algorithm for change propagation tracing tracks the change propagation of design parameters and finds design parameters, constraints and tasks which are probably changed. In the algorithm for change impact analysis, a change impact value is calculated from the list of changeable tasks. These two algorithms have been implemented into change impact analysis system (CIAS). CIAS has been applied to the redesign of 2 stage gear drives. CIAS can improve the efficiency of design activities. If there are many alternatives for a design change at the redesign step, designers can calculate the change impact value of each alternative and perform design change activities in the direction of minimizing design change impact.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.710-715
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• 2004

The design problem of manufacturing system is addressed, adopting the closed queueing network model with multiple loops and re-entrant flows. The entire design problem is divided into two hierarchical sub-problems of (1) determining the station configuration and (2) optimizing the lot constitution; then they are tackled by neighbor search algorithm (NSA) and greedy mean value analysis (GMVA), respectively. Unlike the conventional MVA concerning multi-class closed queueing networks, the GMVA doesn't stick to a fixed lot proportion; rather it tries to find the optimal balance. The NSA, on the other hand, improves the object function value by altering the station configuration successively with its superior neighbor. The moderate time complexity, presented in big-${o}$ notation, enables us to apply the method even to the large-size practical cases, and the CPU time of an enlarged problem can be approximated by the same equation. The validity of our analytic approach is backed up by simulation studies with a widespread simulation package.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.1 s.94
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• pp.75-86
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• 1999

In the assembly system, a pallet plays an important role of transfer and storage. As products become various, many different pallets are also necessary. Since some of them are redundant, a design of pallet with high flexibility is important. This paper suggests design alternatives, in designing pallets with high flexibility. The purpose of this study is to rationalize assembly process of mid-small size products. Every pallet has suitability values depending on characteristic factors of a product, and this value is determined by using AHP (Analytic Hierarchy Process) technique. As the characteristic factors of a product are changed, the suitability value is also changed. Design alternatives can be found by tracing change of the suitability value, which are based on correlation between the characteristic factors of a product and a pallet element.

• Journal of Applied Reliability
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• v.5 no.1
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• pp.167-180
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• 2005

Design of a degradation test without replacement is considered based on tightened critical value to reduce the evaluation testing time. The sample size, number of inspections, and the critical values are determined to assure the same probability of acceptance when the testing time is reduced to some degree. Photo-diode balance of an optical pickup is analyzed as a case study.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.5
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• pp.126-133
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• 2017

This report investigates the stress distribution according to the location and shape change of the circular hole for the lightweight design of the cross beam of a railway passenger car and studies the lightweight design. To design a lightweight cross beam with a circular hole, we selected the non-circular crossbeam as a basic model, examined the stress distribution and displacement by position and determined the location, shape, size and quantity of the hole for light weight. We analyzed the effects of the position and shape of the hole on the maximum equivalent stress and displacement. The influencing factors were set as the design parameters, and the stress value was examined according to the variation of each variable. By considering the stress value according to the change of each variable and selecting the design parameter with the narrowest scattering value of the stress at each position of the hollow cross beam with various hole positions and shapes, we studied a cross beam with a circle hole under identical load condition to have an equal stress distribution to that of a non-circular cross beam.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.434-436
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• 1996

This paper investigates the optimal design of an electronic ballast of half bridge inverter type in consideration of the variation of ambient temperatures for a 15[W] triple-type compact fluorescent lamp. The performances of electronic ballasts under different values or the capacitance ratio in the resonant tank circuit are compared with each other in the practical temperature range between 15[$^{\circ}C$] and 35[$^{\circ}C$] to determine its optimum value. As a result, the optimum value is found to be such that $C_1/C_2=10$ at which value starting of the lamp is most stable and light output reaches its maximum value with lowest variation.