• 한국생산제조학회지
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• 제8권1호
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• pp.119-125
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• 1999

The distribution of fatigue crack growth rate is subjected to the measuring interval and calculated method of growth rate. In this paper, in order to establish the method of determining the distribution of fatigue crack growth rate, which ignores those influences, a series of fatigue crack growth experiments and measuring intervals of crack length calculated reasonable are presented. The main conclusions obtained are summarized as follows: 1) As a result of the ΔP constant test and ΔK constant test, it is thought that an approximate measuring interval of 0.3~0.7mm is reasonable, which allows for few errors and is little subjected to the calculated method of crack growth rate. 2) After generally comparing the error estimation by using the experimental data of CCT specimen with the error rating of the CT specimens, it is possible that the fatigue test has few errors within the measuring interval, ξ(Δa/W)=0.0067~0.017, regardless of the dimension of specimen geometry.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.613-616
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• 2000

This paper considers the problem of subway crew scheduling. Crew scheduling is concerned with finding a minimum number of assignments of crews to a given timetable satisfying various restrictions. Traditionally, crew scheduling problem has been formulated as a set covering or set partitioning problem possessing exponentially many variables, but even the LP relaxation of the problem is hard to solve due to the exponential number of variables. In this paper, we propose two basic techniques that solve the problem in a reasonable time, though the optimality of the solution is not guaranteed. To reduce the number of variables, we adopt column-generation technique. We could develop an algorithm that solves column-generation problem in polynomial time. In addition, the integrality of the solution is accomplished by variable-fixing technique. Computational results show column-generation makes the problem of treatable size, and variable fixing enables us to solve LP relaxation in shorter time without a considerable increase in the optimal value. Finally, we were able to obtain an integer optimal solution of a real instance within a reasonable time.

• 기술사
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• 제36권6호
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• pp.78-81
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• 2003

Physiologically functional food is a type of the processed foods showing bioactivities in a living body. Physiologically functional food is a healthy food reinforcing biofunctional abilities of the precaution and recovering of the illness, immunity reinforcement. bio - rhythm control, aging repression and cancer precaution, etc. The consumers are taking to expect the improvement of national health and extention of life span. etc., Physiologically functional food must be able to be ingested briefly and taken in the surroundings easily and the reasonable price. To achieve this goals, it is necessary to positive support of the authorities concerned, technique development of an educational - Industrial cooperation. establishment of reasonable standard and right understanding of the consumers on physiologically functinal food.

• International Journal of Contents
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• 제6권4호
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• pp.69-78
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• 2010

In recent years, many leading corporations are actively adopting IT as competitive resources to improve productivity and processes efficiency with strategic alignments. In effect, IT investment also continues to increase. As a vast growth of IT investment, questions and criticism on recent IT investment results are also rapidly being raised. Especially, improper decision making and management on IT investment may cause negative impact on the company's reputation and finances, therefore companies need reasonable and wise investment decision making on new IT projects. This study applies the conceptual framework of IT governance to IT investment decision making cases to examine how IT investment governance influences the quality of IT investment decision making and how business-IT strategic alignment affects the quality of IT investment decision making. This paper contributes to identify the main factors for reasonable and effective IT investment decision making and expected to provide proper guidelines for IT investment decision making.

• Structural Engineering and Mechanics
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• 제6권5호
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• pp.571-582
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• 1998

Testing of steel roof purlins is usually performed on full scale models in large vacuum test rigs. To undertake a comparison between web cleat connected purlins and flange bolted purlins a series of tests were performed on a 1:4 small scale model vacuum test rig. Various modelling issues need to be addressed to ensure reasonable comparison with actual constructed roof framing methods but still be suitable for an economical comparison between the connection methods. Model test results were supported by, and found to be in reasonable agreement with, deflection predictions from computer models based on finite element methods. This paper discusses the testing methods adopted and the value of small scale model testing programs as a means of obtaining comparisons between framing options.

• 산업경영시스템학회지
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• 제21권48호
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• pp.263-268
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• 1998

An efficient agricultural marketing system is very important to producers and consumers to keep the reasonable prices. In these days, the main policy for the efficient agricultural marketing system is to enlarge the direct transaction market. But it is not easy to enlarge the direct transaction market in a few years. This paper proposes a new efficient agricultural marketing system that gives a similar effect with the direct market. The proposed system is mainly composed of three associations; producers', consumers' and retailers'association, and the function of the system is devided into material affairs and commercial affairs. The structure of the system also can be simplified as two to three steps. So the system can reduce the cost of logistics and keep the reasonable prices for both producers and consumers.

• 한국잠사곤충학회지
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• 제17권2호
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• pp.171-173
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• 1975

본시험은 진면제조시의 가장 합리적인 정연방법을 구명하기 위한 시험으로서 다음과 같은 결과를 얻었다. 1. 시료견의 정연방법은 0.75% $Na_2$SiO$_3$, 2% NaCO$_3$용액에 40분간 자비하는 것이(T/syb 6/)) 진면 및 수반견사제조면에서 가장 합리적이었다. 2. T$_{6}$구의 진면 및 수방견사는 다른 처리구에 비하여 그 품질이 현저히 우수하였다.

• 대한교통학회지
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• 제13권4호
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• pp.47-59
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• 1995

The main purpose of this study is identifying the factors which affect the mode choice behavior of work trips. Disaggregate behavioral approach is used for the analysis . The data were collected using the questionnaire survey method in Taegu. Two models were developed in this study which are multinomial logit model(MODEL-1) for auto, taxi and bus and multinomial logit model (MODEL-2) for auto, taxi, bus and subway. The stated preference (SP) data were used for the analysis of the subway mode choice behavior. MODEL-1 provide reasonable results for the future application. A multinomial model (MODEL-2) developed using the stated preference(SP) data was tested for the use of future transportation mode. It is four that the those models provides reasonable results in terms of behavioral and statistical consideration.

• 대한교통학회지
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• 제13권4호
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• pp.61-77
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• 1995

The main objective of this research is the development of a logit model of urban workers' auto ownership choice. For the utility specification. a variety of behavioral hypotheses about the factors which affect the urban workers' auto ownership choice are considered. Based on the behavioral hypotheses, a binary logit model of auto ownership is estimated. Empirical estimation is based on a sample of workers taken in Daegu City(1994). The binary logit model of auto ownership development in this paper provides reasonable results in terms of behavioral and statistical considerations. Furthermore, this paper develops several submarket models of auto ownership choice. Market segmentation was made using age, sex, income, home-to-work time distance. It is found that the estimated results with market segmentation are also reasonable. Finally future directions of model development are suggested.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 춘계학술대회 논문집
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• pp.91-99
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• 2001

This paper is for a reasonable selection of design response spectra for the seismic design of specific types of soil-structure interaction systems, e.g., underground structure within flexible soil profiles of structures on the shallow soil layers on the stiff bed rock. the existing backup data used for determining the design response spectra of the Code have been investigated and evaluated. For this purpose, various types of free field analyses have been performed using one-dimensional wave propagation theory considering the nonlinear properties of the soil profile. As a result, a reasonable approach of determining input response spectra for specific soil profiles has been proposed to be compatible to the design response spectra of the Code.