• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.394-398
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• 1994

The aim of the present study was to determine the influence of vibration frequency and muscle contraction level at constant vibration displacement amplitudes on a commonly observed motor response elicited by local vibratory stimulation, i.e., the Tonic Vibration Reflex (TVR). Vibration was applied to the distal tendons of the hand flexor muscles. Changes in activity of the hand flexor and extensor muscles were analyzed as a function of the vibration frequency (40-200 Hz), displacement amplitude(200.mu.m and 300.mu.m peak-to-peak), and the initial contraction level of the flexor muscles (0%, 10%, and 20% of the maximal voluntary contraction: MVC). The main results indicate that the TVR increases with vibration frequency up to 100-150 Hz and decreases beyond, and the TVR attains its maximum at 10% MVC. It appears that high frequency vibration tends to induce less muscle/tendon stress. Such a result is of particular importance for the design of handheld vibrating tools.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.1071-1078
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• 2006

Robust design of products or processes is a way to produce products or processes with less variability on condition that the product specification is met, so that the ratio of nonconforming products can be as minimized as possible. In such models as robust parameter design(RPD) originated by Taguchi and response surface methodology(RSM), the variances of noise variables are assumed to be measurable. However, there are circumstances in which the experimenters are unable to measure noise variables or perhaps are not aware of what the noise variables are. In this paper, it is demonstrated through an example that Taguchi's RPD approach can be conducted within the framework of the analysis of variability, with a view to a comparison of the two methods.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.11a
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• pp.531-534
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• 2006

Response surface methodology (RSM) is a useful collection of experimentation techniques for developing, improving, and optimizing products and processes. When we are to estimate second-order regression model and optimize quality characteristic by RSM, central composite designs and Box-Behnken designs are widely in use. However, in developing cutting-edge products, it is very crucial to reduce the time of experimentation as much as possible. In this paper small-sized second-order designs are introduced and their estimation abilities are compared in terms of D-optimality, A-optimality, and variance of regression coefficients, ease of experimentation, number of experiments. Then we present a guideline of using specific designs for specific experimentation circumstances. The result of this study will be beneficial to experimenters who face experiments which are expensive, difficult, or time-consuming.

• Journal of the Korean Operations Research and Management Science Society
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• v.36 no.1
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• pp.57-68
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• 2011

This paper examines how multiple performance feedbacks influence firm's technological search, using two types of indicators : accounting-based performance and market-based performance. Also we investigate how CEO's attention shift depends on firm specific factors such as firm size and outsider ownership. For empirical analysis, we utilized financial data on 675 manufacturing firms in Korea during the period between 1998 and 2009. The results show that technological search based on accounting-based performance feedback is moderated by focal firm's size. However, as outsider ownership increases, technological search increases in response to market-based performance feedback.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2008.10a
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• pp.37-62
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• 2008

Recent market environment shows a new relationship between customer and company. You can easily observe customers take initiatives to get involved in the marketing activities such as product development, pricing and distribution etc. Despite the fact there are a lot of marketing activities initiated by customers in the online travel market, customer participation has been given little attention in the academic literature. Our research is grounded in the well-known commitment-trust theory of relationship marketing, originally proposed by Morgan and Hunt(1994). According to the theory, trust is central to successful relationship marketing. This study explores the effect of trust on customer participation in the online travel market. Consequently, this study suggests some managerial implications for marketing strategies in response to customer initiative in the marketing activities on the online travel market.

• Journal of the Korean Operations Research and Management Science Society
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• v.39 no.1
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• pp.49-67
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• 2014

This paper proposes a real time pricing model for smart grid considering consumers' behavior, real time price elasticity, and exogenous price. Based on the proposed model, we found the weight of utility over cost is the most sensitive factor compared to other factors. Also, if the electricity price is set to be changed too sensitively to energy consumption, it is warned that real time pricing sometimes can cause increment of peak-time demand and volatility. Finally, real time pricing could be less efficient when the difference between the maximum and the minimum consumption level is small.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.1077-1084
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• 2003

The performance of simulated annealing (SA) algorithm such as solution optimality and computation time mainly depends on how to determine the SA-related parameters Several schemes have been suggested to improve the performance of SA and several parameter design methods have been utilized to select parameter values of each scheme. In this paper, we propose a new SA algorithm design method that can determine schemes as well as parameter values simultaneously The new SA algorithm design method is based on the Taguchl method which primarily selects the design parameters for a product or process to minimize the effect of noise parameters. so that the response is close to the desired target with minimum variation. To show the effectiveness of the proposed method, extensive computation experiments are conducted.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.351-355
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• 2003

유행에 민감한 의류업계의 생명은 빠른 대응이다. 특히 중국은 인구가 많고, 국토 면적이 넓어서 동북부와 남부 및 서부지역에서 계절의 변화가 뚜렷한 차이를 보이고 온도 차이가 큼으로 하여 같은 시점에서 서로 다른 계절의 의류가 요구되거나 유행되고 있는 것이 특징이 다. 본 연구에서는 중국의 특성에 맞추어 중국현지의 의류유통회사(약칭 S사)의 생산과 판매중심의 시장대응형 프로세스를 구축하여 상품기획에서부터 상품발주, OEM생산, 입하, 배분, 출하, 판매, 실적집계, 판매평가, 보충출하, 보충생산, 히트상품 및 유사품 재발주 등 일련의 과정을 포함하는 정보망을 구축하여 각 과정에서 발생하는 정보를 실시간으로 집계하고 다각도에서 분석하여 더 빠르고 더 정확한 영업의사결정의 지원을 목적으로 하였다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.10a
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• pp.225-228
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• 1996

This paper proposes a design methodology for distributed databases connected by a LAN. Two primary objectives of the methodology are (i) to allocate data files and workload among heterogeneous servers and (ii) to determine the number of servers to satisfy the response time required for processing each transaction. The file and workload allocation decision is formulated as a nonlinear zero-one integer programming problem. This problem is proven to be NP-complete. A heuristic is developed to solve this problem effectively. A decision support system is implemented and an example is solved to illustrate the practical usefulness of the system.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.131-134
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• 1996

Application of machine learning to scheduling problems has focused on improving system performance based on opportunistic selection among multitudes of simple rules. This study proposes a new method of learning scheduling rules, which first establishes qualitatively meaningful criteria and quantitatively optimizes the use of them, a similar way as human scheduler accumulate their expertise. The weighting of these criteria is trained in response to the system states through simulation. To mimic human quantitative feelings, distributed fuzzy sets are used for assessing the system state. The proposed method was applied to job dispatching in a simulated FMS environment. The job-dispatching criteria used were the length of the processing time of a job and the situation of the next workstation. The results show that the proposed method can develop efficient and robust scheduling strategies, which can also provide understandable and usable know-hows to the human scheduler.