• 한국시스템다이내믹스연구
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• 제2권2호
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• pp.41-62
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• 2001

Perhaps, one of the typical emerging markets drawing tremendous attention from not only business professionals but also policy-makers would be the mobile Internet services. In recent years many research institutes reported their predictions on the growth of the mobile Internet services market, announcing that the market would show explosive growth and replace the wired Internet service market rapidly. Unfortunately, however, the reality we are facing at present is quite different from their expectations. The realized share of the mobile services in Korea last year has turned out remaining only about one percent of the total network service revenue. What are the reasons for the gap between the prospects and the reality? Starting from this question, this paper attempts to explore the generic pitfalls of the traditional number-crunching methods adopted thus far for the forecast of newly emerging market trends, and present an alternative by introducing systems thinking to the mobile Internet service market as an example, followed by its rationale as a new tool for forecasting and some reasoning about why traditional methods are no longer appropriate.

• Journal of the Korean Statistical Society
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• 제29권2호
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• pp.219-229
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• 2000

Oh et al.(1999) 3$\times$2 crossover design for assessing bioequivalence when two new generic drug formulations and innovator are simultaneously considered. This design is not only more efficient than 3$\times$3 one, proposed by Lee et al.(1998), in practical sense, but also more ethical in medical sense. However, the general statistical methods are not directly applicable to both designs when subjects are dropped out in the experiment, even though it is always possible in bioavailability and bioequivalence studies because of some administrative and economic reasons. In this research we propose an inference to drug effects when subjects are dropped out in the planed-for 3$\times$3 and 3$\times$2 crossover experiments. An example is given for illustration.

• 대한안전경영과학회지
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• 제17권2호
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• pp.191-199
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• 2015

Considering the supply system and operating cost of enterprises which are in the supply chain as the main index, this paper establishes a supply chain evaluation model, and utilizes Arena building stimulation model of the supply chain which considers manufacturing enterprises as the core of supply chain. This model designs a generic simulation model of the supply chain including multi-level distributors and suppliers. And the model analyzes a representative example of business process, one of the enterprises in Shandong.

• 한국문헌정보학회지
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• 제47권3호
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• pp.321-342
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• 2013

본 연구에서는 이미지 인지유형 및 질의방식에 따른 검색방법의 효율성을 분석하기 위해 32명의 대학생들이 구글 이미지 검색시스템을 이용하여 검색실험을 실시하였다. 이미지 인지유형은 구체적(specific), 일반적(generic), 추상적(abstract) 유형으로 구분하였으며, 각 유형별 이미지를 텍스트검색, 예제에 따른 검색(QBE: Query by example), 하이브리드검색 등 3가지 질의방식으로 구분하여 실험을 실시하였다. 독립변수는 이미지 인지유형 및 질의방식이며 종속변수는 검색된 적합한 이미지의 수이다. 데이터 분석은 일원배치 분산분석(One-way ANOVA)과 이원배치분석(Two way ANOVA)을 이용하여 검증하였다. 분석결과로는 구체적 이미지와 일반적 이미지 인지유형에서는 텍스트 및 하이브리드 방식이 검색효율성이 높게 나타났고 추상적 이미지 인지유형에서는 QBE이 검색효율성이 높은 것으로 나타났다. 본 연구 결과는 이미지 검색에서 검색효율성을 높이기 위한 방안을 마련하는데 기초자료로 활용될 수 있을 것이다.

• Structural Engineering and Mechanics
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• 제28권1호
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• pp.53-67
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• 2008

Anisotropic materials are increasingly required in modern technological applications. Certainly, civil, mechanical and naval engineers frequently deal with the situation of analyzing the dynamical behaviour of structural elements being composed of such materials. For example, panels of anisotropic materials must sometimes support electromechanical engines, and besides, holes are performed in them for operational reasons e.g., conduits, ducts or electrical connections. This study is concerned with the natural frequencies and normal modes of vibration of rectangular anisotropic plates supported by different combinations of the classical boundary conditions: clamped, simply - supported and free, and with additional complexities such holes of free boundaries and attached concentrated masses. A variational approach (the well known Ritz method) is used, where the displacement amplitude is approximated by a set of beam functions in each coordinate direction corresponding to the sides of the rectangular plate. Consequently each coordinate function satisfies the essential boundary conditions at the outer edge of the plate. The influence of the position and magnitude of both hole and mass, on the natural frequencies and modal shapes of vibration are studied for a generic anisotropic material. The classical Ritz method with beam functions as spatial approximation proved to be a suitable procedure to solve a problem of such analytical complexity.

• 한국시스템다이내믹스연구
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• 제5권2호
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• pp.67-88
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• 2004

This paper attempts to explore the generic pitfalls of the traditional number-crunching methods adopted thus far for the forecast of newly emerging market trends, and present an alternative by introducingsystems thinking to the portable Internet service market as an example, followed by its rationale as a new tool for forecasting and some reasoning about why traditional methods are no longer appropriate. Most adoption models in general to forecast market trends have several limitations due to theirbasic assumptions and prospective. First, they fail to capture dynamic interactions among the factors involved over time, with implicit assumptions of 'unilateral causality' in that each factor contributes as a cause to the effect, i.e., causality runs one way; each factor acts independently the weighting factor of each is fixed, etc. Second, the number-crunching models have no way of taking into account the impact of delayed feedback often caused by introducing new policies and legislative changes on the whole system under investigation. Third, there is not a way to reflect the effect of competition by players.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.217-224
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• 2003

ISO 14649 is a new interface (or language) standard for the CAD-CAM -CNC chain, currently under establishment by ISO TC184 SCI and SC4 . Upon completion, it will replace ISO 6983, so called M amp; G codes used for CNC since 1950' s. As the new language is being established, a new CNC controller called STEP-CNC (STEP­compliant CNC), capable of carrying out various intelligent tasks using the new language as an input, receives worldwide attention. In this paper, we present a distributed architecture for STEP-NC system based on the generic paradigm of STEP-NC. The STEP-NC system is consisted of 3 sub-systems: 1) CGS (Code Generation System), 2) CES (Code Edit System), and 3) ACS (Autonomous Control System). Also presented in this paper is algorithm for delta volume decomposition, a crucial algorithm for developing CGS. First method is based on the cutting tool and the second method is based on the turning features commonly used in the shop floor. An illustrative example is given to compare the two methods, and to illustrate usage scenario of the delta volume in the turning STEP- NC system under development.

• 대한안전경영과학회지
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• 제16권3호
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• pp.377-388
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• 2014

There have been a lot of studies about overseas factory location in order to meet various needs of industries according to the international economic developments. However, most of the studies were written about generic theory for general industries or mainly concerned to high capital industries. This study is focusing on the sewing and apparel industries which represent labor intensive and small-medium type of enterprises. For this study, AHP(Analytic Hierarchy Process) methods were applied to make proper analysis after wide range of survey to clarify determinants which provide a guidance for overseas factory location. As a result of the analytical researches done in the thesis the most important which should be taken consideration while determining of overseas factory location for sewing and apparel products industry are as follows - economic factors(0.569), geographic factors(0.171), social and cultural factors(0.157), regulations and institutional factors(0.103). In the last, S company is examined for example to show how this determinants have practically been applied.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.176-183
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• 2003

This paper presents a neural network based approach to disseminating information relating to experimental and field observations in engineering. Although the methodology is generic and can be applied to many areas of engineering science, attention is focussed here solely on geotechnical engineering applications. Field data relating to the settlement of foundations presented by Burland and Burbidge (1985) which led to their well known equation for calculation of settlement, now included in most text books, is re-visited. A part of the data, chosen randomly, is used to train an Artificial Neural Network (ANN), which relates foundation settlement to various causes as identified by the authors. Predictions are made for situations for which data were not used in training. These indicate sufficient accuracy when compared to the original field data. Accuracy of predictions is further improved when all the data are included in the training set. The finally trained ANN is shown to represent these data more accurately than the Burland and Burbidge equation. Based on the above heuristic example, an ANN is presented as an alternative to developing equations and design rules in geotechnical engineering practice. Significant advantages are shown to arise by using this methodology. Ease of updating the ANN, as and when additional data becomes available, being the most important one. Loss of transparency, however, seems to be the main disadvantage.

• 한국식품위생안전성학회지
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• 제14권1호
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• pp.104-114
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• 1999

This study was conducted to find out the proper ways of implementation of Hazard Analysis Critical Control Point (HACCP) concepts applicable to the current Korean food inspection system. The following recommendations are based on an in-depth review of the Canadian Food Safety Enhancement Program (FSEP), which is one of the leading HACCP programs adapted to the food industry. Since 1997, the HACCP system has been voluntarily applied to meat processing plants in Korea in accordance with the Food Protection Law. But the guidelines are obscure and inadequate to expand to the diversity of food plants, and are therefore only applied to a limited number of plants of small scale enterprise. For these reasons, it is necessary to prepare an enhanced food safety control program focused not only on the HACCP plants but also on the non-HACCP plants. The national program should be the fundamental framework of a food safety control policy enforced by all the relevant authorities. The Prerequiste Program of Canadian Food Inspection Agency and Sanitation Standard Operating Procedures (SSOP) of FSIS are good example programs for the non-HACCP plants. These programs, which are a major part of the HACCP system, could easily be adapted to the Korean food industry. To improve the current HACCP implementation guideline, it is necessary to develop a detailed implementation manual, generic HACCP model, training program, and an audit program.