• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5622-5632
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• 2011

This paper presents the simulation design and analysis of Integrated Logistics System(ILS) which is operated by using the AGV(Automated Guided Vehicle). To maximize the operation performances of ILS with AGV, many parameters should be considered such as the number, velocity, and dispatching rule of AGV, part types, scheduling, and buffer sizes. We established the design of experiment in a way of Orthogonal Array in order to consider (1)maximizing the throughput; (2)maximizing the vehicle utilization; (3)minimizing the congestion; and (4)maximizing the Automated Storage and Retrieval System(AS/RS) utilization among various critical factors. Furthermore, we performed the optimization by using the simulation-based analysis and Evolution Strategy(ES). As a result, Orthogonal Array which is conducted far fewer than ES significantly saved not only the time but the same outcome when compared after validation test on the result from the two methods. Therefore, this approach ensures the confidence and provides better process for quick analysis by specifying exact experiment outcome even though it provides small number of experiment.

• Journal of KIISE:Software and Applications
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• v.33 no.3
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• pp.277-288
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• 2006

Product line engineering (PLE) is a new effective approach to software reuse, where applications are generated by instantiating a core asset which is a large-grained reuse unit. Hence, a core asset is a key element of PLE, and therefore the reusability of the core asset largely determines the success of PLE projects. A tore asset is a reusable part not a whole system, and supports not only variable functions but also common functions. However, there are limitations to evaluate reusability of core asset that has these unique characteristics. This paper proposes a comprehensive quality system for evaluating the reusability of core assets, based on ISO/IEC 9126. We first identify the key characteristics of core assets, and derive the set of quality attributes that characterizes the reusability of core assets. finally, we define metrics for each quality attribute. In addition, we provide guidelines for applying the metrics and perform a case study based on rental product line. Using the proposed quality system, reusability of core assets can be more effectively and correctly evaluated.

• Journal of Navigation and Port Research
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• v.44 no.6
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• pp.550-556
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• 2020

Over the past years, the role of ports in the global network of supply chains has becoming increasingly important, not merely as a physical location for loading and unloading goods, but also as an essential center of economic activity where additional value is added to cargo. Due to the overall growing importance of ports, each country has chosen to adopt hub growth as a primary economic strategy. Northeast Asia in particular, due to its high population density, experiences intense competition between its ports. Busan's port, as a result, has used the establishment of Distripark in order to attract high and stable trade volume, and compete more effectively with other ports in the region. This study estimates the unit cost of the logistic process for the all principal cargos handled at Busan New Port, with the findings revealing that unit cost increases gradually starting with chemical products, LME bulk goods, automobile parts, LME containers, general cargoes, and LME inland transportation goods coming in last. Future research will look more closely at all all categories of cargo handled in the Distrpark of Busan New Port, thereby enabling us to better understand the value created by the port, and how to best implement effective trade volume-attraction strategy.

• Journal of Legislation Research
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• no.54
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• pp.111-154
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• 2018

The protection of fundamental rights of people is a natural duty of a state. Since Constitutional Law declare that a state is obliged to protect the fundamental rights of people obviously, it is reasonable to postulate that a state has a duty to protect every person's right much more positively. Of course, it is true that whereas right of freedom is much more important in modern states, the social right becomes more important currently. Nevertheless, we have no choice but to put an emphasis on the importance of the right of freedom like modern states. Thus states are still bound to try to protect the right of people, specific duty of behavior for the sake of right of freedom belongs to states. In particular, due to the fact that lifts are essential to our comfortable life and the demage from the accident concerning with the lifts is fatal, the strategy for securing the safety of using the lifts is significant to some extent. And because it is true that the experience of UK that put an emphasis on the role of civil actors is meaningful to us, there seems implications for us. Accordingly, it is possible to consider the material components such as the check of safety before installation for the sake of safety enhancement, quality control for lifts parts, specification of check criterion and variation of check cycle etc. and personal ones such as specification of qualification of competent persons, guarantee of competent person's independence, variation of obligator's duty and variation of user's obligation etc. However, as the situation of UK is one thing and that of Korea is another, we don't have to adhere to the policy and the experience of UK strictly. Rather, we had better apply the policy and experience of UK to ours appropriately.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.4
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• pp.107-111
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• 2020

Recently, as an aging society progresses, a lot of interest in health and diagnosis is increasing, As the field of various bio-imaging systems for guided surgery capable of accurate diagnosis has emerged as important, a Fluorescence imaging system capable of accurate measurement and real-time confirmation has emerged as an important field. Fluorescence images currently being used are mainly in the NIR-I band, but many studies are in progress in the NIR-II band in order to improve resolution and confirm fluorescence deeply and accurately. In this paper, the difference between NIR-I and NIR-II, optical characteristics, and SBR (signal to background ration) of a fluorescent imaging system, was investigated using the finite element (FEM) method. After confirming, it was confirmed that the SBR was 16.2 times higher in the NIR-II area than in the NIR-I by making the skin phantom and measuring the fluorescence. It is confirmed that the enhancement in SBR of the Fluorescence imaging system is more effective in the NIR-II region than in the NIR-I region and expected to be used in application fields such as guided surgery, bio-sensor and also device which can detect the defect of optical devices.

• Journal of the Korean Geographical Society
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• v.28 no.4
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• pp.285-297
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• 1993

For the application of the diffusion equation, slope height and maximum slope angle are calculated from the plotted slope profile. Using denudation rate as a solution for the diffusion equation, an apparent age index can be calculated, which is the total amount of denudation through total time. Plots of slope angle versus slope height and apparent age index versus slope height are useful for determining relative or absolute ages and denudation rates. Mathematical simulation plots of slope angle versus slope height can generate equal denudation-rate lines for a given age. Mathematical simulations of slope angle versus age for a given slope height, for equal denudation-rate at a particular profile site, and for comparing to other sites having controlled ages.

• The KIPS Transactions:PartD
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• v.12D no.6 s.102
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• pp.869-874
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• 2005

In the recent years there has been an increase of service competition in the activity of product selling, especially in the extension of warranty coverage and qualify. The variables in connection with the service competition are not crisp, and required the expertise of the production line. It thus becomes all the more necessary to use subtler tools as decision supports. These problems are typical not only of product companies but also of financial organizations, credit institutions, insurance, which need predictions of credibility for firms or persons in which they have any kind of interest. A suitable approach for minimizing the risk is to use a knowledge-based system. Most often expert systems are not standalone programs, but are embedded into a larger application. The aim of this paper is to discuss an approach for developing an embedded fuzzy expert system with respect to the product selling policy, especially to present the decision system of automobile selling activity around the extension of warranty coverage and quality. We use the MATLAB tools which integrates computation, visualization, and programming in an easy-to-use environment where problems and solutions are expressed in familiar mathematical notation. Also, we present the API functions embedding into the existing application.

• Korean Journal of Construction Engineering and Management
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• v.15 no.1
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• pp.101-110
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• 2014

The ministry of Land, Infrastructure and Transport announced that they launched the pilot project to offer Happy House built with modular construction as part of the major projects of incumbent government in 2013. The market size of modular construction is getting increasingly enlarged together with strong will of government. The major challenges that current modular construction encounters can be summed up as lack of standardization of material on the stage of design and fabrication. The portion of material costs in modular construction marks 16 to 17% higher than the existing other construction method, and account for 60 % of total construction cost, which is why material management is the most important factor. However, the imperfect standardization and specification on design causes high loss of materials on fabrication, which makes the construction wastes and total construction cost increasing in accordance with the increase of material costs. This study has been conducted to verify major modules by developing optimization algorithm on gypsum board material among wall finishing materials. It is expected that this paper contributes not only to eco-friendly construction by minimizing the waste factors of materials through these efforts, but also to removing high cost issues which had been recognized as a setback of current modular construction.

• International Commerce and Information Review
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• v.16 no.4
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• pp.281-305
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• 2014

The purpose of this study is to empirically analyze the status and the trends in the international competitiveness of Korean export products against MINTs. For the study, the data were collected from the trade statistics for the period 2009-2012 produced by KITA and UN comtrade, and trade specialization index and market comparative advantage index were selected as index analysis methods. The findings from this study are as follows: First, Korea maintains a continuous increase of trade volume and trade balance in trade with MINTs, and exports finished goods, auto parts, etc. to MINTs, whlie mainly imports primary products such as energy fuels from MINTs. Second, Korea remains competitive in both product groups and individual products over MINTs. Third, even though Korean exports obtain a high competitiveness against MINTs, its competitiveness shows the differences by country. Several implications of this study are as follows: First, we need to take full advantage of energy resource-rich MINTs in securing stable energy fuels. Second, we should prepare response plans for the economic conditions which can have a negative impact on trade with MINTs, Third, we need to build strategies for maintaining the competitiveness of Korean exports over MINTs. Fourth, The differentiated export strategies should be established by country by considering differences in Korean exports' competitiveness which exist among the four countries of MINTs. Fifth, we need to prepare for such a situation which MINTs attempt to expand its influence by forming a collective economic cooperation.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.71-71
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• 2017

농용트랙터의 운전자는 작업, 주행으로 인한 유해한 저주파 진동에 장시간 노출된다. 이에 따라 운전자에게 전달되는 노면 진동을 감소시켜주기 위한 전방차축 현가장치의 역할이 커지고 있다. 트랙터의 전방차축 현가장치는 주로 유압식으로 설계되어 있으며 이를 구성하는 유압요소 선정이 현가장치의 성능에 중요한 영향을 미친다. 하지만, 실제와 유사한 조건에서 트랙터 차체 무게만큼 큰 부하를 제공하여 유압회로의 성능을 실험하는 것은 비용과 시간 측면에서 비효율적이다. 본 연구에서는 이를 대체하기 위하여 개별 유압요소의 성능을 테스트 할 수 있는 현가장치 유압회로 요인 시험기를 설계제작 하였다. 이를 이용하여 개별 부품의 성능곡선을 센서를 이용 측정하였고 얻은 특성값을, 구성한 유압 시뮬레이션 모델에 반영하여 실제조건의 유압특성을 얻을 수 있는 유효한 시뮬레이션 모델 개발에 활용하였다. 또한, 실험실 환경에서 유압식 현가장치를 간소화 시킨 형태로 유압회로의 성능을 예비시험해 볼 수 있도록 다양한 센서를 장착 데이터를 취득할 수 있도록 하였다. 개발한 요인 시험기는 하부에 설치된 가진 실린더를 이용하여 상부에 설치된 현가장치 실린더의 스트로크 변위와 속도에 따른 힘을 측정할 수 있도록 구성하였다. 이를 위해 현가장치 실린더의 헤드부와 로드부에 각각 압력센서를 설치하였으며 헤드부, 로드부의 압력 차이와 로드셀을 이용해 측정한 가진 실린더의 힘의 관계를 확인하였다. 상부의 현가 실린더 장치는 복동 형태로 제작되어 헤드부, 로드부 양쪽 방향으로 유량이 흐를 수 있도록 설계되었다. 이를 이용해 헤드부와 로드부 사이에 어큐뮬레이터, 가변 오리피스, 릴리프 밸브 등으로 유압회로를 구성하였으며 어큐뮬레이터 용량에 따른 힘의 변화, 가변 오리피스의 개도량에 따라서 전달되는 힘의 크기 등을 측정하였다. 하부의 가진 실린더는 사인파, 삼각파, 계단 입력, DC 레벨 등의 신호를 발생시킬 수 있도록 제작되었다. 신호의 주파수는 0~4Hz, 범위에서 사용자가 조절할 수 있도록 설정되었으며 계단응답 성능 측정 시험을 평가한 결과 정상상태오차는 0.470mm~0.536mm, 입상시간은 0.194초~0.202초, 정착시간은 0.230초~0.421초로 나타났다.