• Toxicological Research
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• 제14권2호
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• pp.273-283
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• 1998

Single and 4 weeks oral administration of New wonbangwoohwangchungsimwon (NSCH) which was used l-muscone as substitutive material qf musk, to beagle dogs of both sexes were per-formed to investigate both acute and subacute toxicity. Beagle dogs (3 males and 3 females) in acute experiments were administered orally with single dose of 2,000 mg/kg and groups of 9 male and 9 female beagle dogs in subacute experiments were given daily different dosage of NSCH, 160 mg/kg/day (low dosage group), 400 mg/kg/day (middle dosage group), 1,000 mg/kg/day (high dosage group) once a day for 4 weeks by oral route according to the Established Regulation of Korea Food and Drug Ad-ministration (l996. 4. 16). $LD_{50}$ value for beagle dogs was more than 2,000 mg/kg per oral for both male and females. In animals administered with NSCH, there were neither dead animals nor significant changes of body weights. In addition, no differences were found between control and treated groups in clinical sign, urinalysis, eye examination, hematology, serum chemistry, organ weight and other fingings. No histological lesions were observed in both control and treatment groups. Above data strongly suggset that NSCH in beagle dogs is considered to be safe.

• Toxicological Research
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• 제14권2호
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• pp.249-260
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• 1998

Single and 4 weeks oral administration of New Woohwangchungsimwon (NWCH) which was used l-muscone as substitutive material of musk, to beagle dogs of both sexes were performed to investigate both acute and subacute toxicity. Beagle dogs(3 males and 3 females) in acute experiments were administered orally with single dose of 2,000 mg/kg and groups of 9 male and 9 female beagle dogs in subacute experiments were given daily different dosage of NWCH, 160 mg/kg/day (low dosage group), 400 mg/kg/day (middle dosage group), 1,000 mg/kg/day (high dosage group) once a day for 4 weeks by oral route according to the Established Regulation of Korea Food and Drug Administration (1996. 4. 16). $LD_{50}$/ value for beagle dogs was more than 2,000 mg/kg per oral for both male and fe-males. In animals administered with NWCH, there were neither dead animals nor significant changes of body weights. In addition, no differences were found between control and treated groups in clinical sign, urinalysis, eye examination, hematology, serum chemistry, organ weight and other fingings. No histological lesions were observed in both control and treatment groups. Above data strongly suggset that NWCH in beagle dogs is considered to be safe.

• 한국멀티미디어학회논문지
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• 제17권8호
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• pp.946-952
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• 2014

Mobility prediction is one of hot topics using location history information. It is useful for not only user-level applications such as people finder and recommendation sharing service but also for system-level applications such as hand-off management, resource allocation, and quality of service of wireless services. Most of current prediction techniques often use a set of significant locations without taking into account possible location information changes for prediction. Markov-based, LZ-based and Prediction by Pattern Matching techniques consider interesting locations to enhance the prediction accuracy, but they do not consider interesting location changes. In our paper, we propose an algorithm which integrates the changing or emerging new location information. This approach is based on Active LeZi algorithm, but both of new location and all possible location contexts will be updated in the tree with the fixed depth. Furthermore, the tree will also be updated even when there is no new location detected but the expected route is changed. We find that our algorithm is adaptive to predict next location. We evaluate our proposed system on a part of Dartmouth dataset consisting of 1026 users. An accuracy rate of more than 84% is achieved.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1991년도 춘계공동학술대회 발표논문 및 초록집; 전북대학교, 전주; 26-27 Apr. 1991
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• pp.67-76
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• 1991

For several years, graduate students and faculty of the Engineering Systems Research Center at U.C., Berkeley have been studying new methods of planning and scheduling in a computer integrated manufacturing environment, with particular emphasis on large scale integrated circuit fabrication. One part of this work, focusing on short interval scheduling, uses simulation models as a primary research tool. We have built two versions of the same basic model (programmed in C) to study two different problems (one deals with machine down time and the other with setup times). These have proven to be efficient for studying particular problems, but are difficult and time consuming to modify. We are convinced that our research will be more effective: (1) if it were easier to build special purpose models tailored to the research question at hand; and (2) if we had better interfaces to graphics output. Commercially available factory simulators are inadequate for this research for a variety of reasons. Existing packages such as SIMKIT, SLAM, SIMAN and EXCELL have their own weaknesses. Typically, they are hard to develop and to modify. They do not allow for adding new dispatching decisions or release decision. Also, it is hard to add more machines to existing environment or change the route the product flows. For these various reasons, we had developed a new simulation package having flexibility and modularity. In this paper, based on experiences gained in the application of object oriented programming, we discuss unique features of the simulator developed in OOPS and ways to take advantage of features in developing and using manufacturing simulation software written in the OOPS

• 한국항공운항학회지
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• 제14권2호
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• pp.45-55
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• 2006

Air transportation industry becomes more competitive because that the restrictions on new access to market were eased and related enough for each airline to choose the freight rate and the route without rein. New competitors are pursuing convergence strategy which focuses on low freight rate as a niche strategy for increasing market share by stimulating low cost demand. This strategy is now spreading all over the world such places as Europe, Asia, Oceania and etc. As of December 1, 2004, hundreds of low cost carriers are participating actively in the market and finding their level as a new strategic group in the air transportation industry with expanding their market. In case of USA, however, many airlines, which had newly entered to the market, went into bankruptcy in the mid-1980s. People Express in USA established in 1980 is one of the examples of failure. In case of Japan, Hokkaido International Airline, a typical low cost carrier which established in 1997, filed for bankruptcy. This study is for examining the strategic implication closely through the study on management strategy and cases of failure of low cost carriers.

• 한국철도학회논문집
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• 제12권5호
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• pp.778-787
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• 2009

본 논문은 우리나라에서 철도가 가져온 사회경제적 변화에 대해 분석하였다. 우리나라 철도는 1899년 개통된 이후 금년으로 110주년이 되었는데 철도는 그동안 교통뿐만 아니라 국토의 공간구조, 새로운 도시의 형성 등 사회경제적으로 큰 영향을 미쳤다. 대전은 좋은 예의 하나이다. 본 논문에서는 철도가 가져온 변화를 구체적인 사례를 통해 통행시간의 변화, 도시발전과 인구변화, 산업의 변화, 문화와 관광의 변화 등을 분석하였다. 향후 이러한 연구는 다른나라와의 비교연구를 통해 철도가 가진 보편적인 기능과 한국철도의 독특성을 파악하는데 도움을 줄 것이다.

• 한국농공학회지
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• 제33권2호
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• pp.104-111
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• 1991

In Korea, small-scale reclaimed areas have been suffering from many problems because of the lack of comprehensive developing strategy although considerable investments have been inputed by the public sector since 1970's. For 3 reclaimed sites in Chonnam Province choser as case study areas, the analysis, the second attempt of widely-spanned studies on areal conditions, concentrated on their farming and economic conditions. Its results were as follows ; 1. Although farming pattern has been transferred to the full4ime rice cropping type by the creation of reclaimed paddy field, farming size in the areas has not been increased more than that in existing agricultural areas. This means that agricultural planning should be included in the initial stage of reclamation projects, especially with reference to the substantial enlargement of farming size. 2. Block parcelling of severely fragmented holdings in new and old lands should be carried out, which can make farming activities efficient and farming route shortened. In large-scale reclaimed areas, new village planning could be considered in its central zone for efficent farming. 3. Because soil in the areas contains much more salt and water than that in other areas, new design methodology should be introduced for the efficient use of agricultural machines in reclaimed areas. 4. There are deep-seated economic problems in reclaimed area, which have been caused by very poor level and agriculturally dominated structure of household income. These problems should motivate farmers to give up positive action for qualitative and quantitative improvement in farming.

• 한국항해항만학회지
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• 제44권3호
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• pp.235-243
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• 2020

부산항은 컨테이너 물동량 기준으로 세계 6위의 항만이며, 환적화물 기준으로 세계 2위의 항만으로 큰 기능을 하고 있다. 그러나 항만시설 및 운송업체에 대한 정책적 배려 부족으로 부산 신항내 환적화물의 운송과 배후물류단지 화물운송에 있어 과적단속이 심각한 문제로 대두되고 있다. 이에 관련 운전자, 운송업체, 항만 배후물류단지 담당자를 대상으로 그 실태를 살펴보고, 그 문제점을 파악한 후 개선방안을 제언하였다.

• 한국지형학회지
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• 제24권4호
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• pp.103-115
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• 2017

This paper shows the types of deteriorated hiking trails and degrading factors at three Great Walks such as Tongariro Alpine Crossing, Routeburn Track and Kepler Track in New Zealand. The deteriorated trails could be classified into gullying, widening, narrowing, branching and sidewall erosion. Department of Conservation carefully manages overland flows on trails for preventing surface erosion, thus the Great Walks show only a minor problem of gully on trails which is usually active in a mountainous area. Widening and branching of trails caused by tread erosion are not also developed due to the restriction of visitors as well as the management of rainwash. However, despite the detailed maintenance and prevention of an overuse of trails, some trails traversing steep slopes in a alpine zone under a periglacial environment are severely degraded along their sidewalls. It suggests that a unvegetated sidewall of trails has to be strictly managed in an early stage of occurrence and a slope-traversing section should be selected with more consideration when establishing a route of hiking trails.

• 한국항해항만학회지
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• 제45권2호
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• pp.54-60
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• 2021

The aim of this study is to determine the critical factors and construction requirements for a new deep-water seaport system in the Lach Huyen area in northern Vietnam. In this study, the Analytic Hierarchical Process (AHP ) method was used to evaluate the importance of the criteria and subcriteria. The results were as follows: the principal criterion "geographical location (0.151)" ranked as the most important criterion for building a new deep-water port system, which is affected by the subcriteria "direct sea route with mega-vessel" and "good liner connectivity index". The principal criterion "port competency (0.145)" ranked second; thus, it can be concluded that good competitiveness of a port' will provide many benefits to the port and the region. Regarding the implication, the established evaluation framework can be used for port construction to make a more reasonable judgment. In a future study, the scope of evaluation factors should be widened, involving participation of broader stakeholders, such as shipping companies, forwarders, and logistics companies.