• International Journal of Fluid Machinery and Systems
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• 제9권2호
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• pp.143-149
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• 2016

In this study, a method for the multi-objective optimization of an impeller for a centrifugal compressor using fluid-structure interaction (FSI) and response surface method (RSM) was proposed. Numerical simulation was conducted using ANSYS CFX and Mechanical with various configurations of impeller geometry. Each design parameter was divided into 3 levels. A total of 15 design points were planned using Box-Behnken design, which is one of the design of experiment (DOE) techniques. Response surfaces based on the results of the DOE were used to find the optimal shape of the impeller. Two objective functions, isentropic efficiency and equivalent stress were selected. Each objective function is an important factor of aerodynamic performance and structural safety. The entire process of optimization was conducted using the ANSYS Design Xplorer (DX). The trade-off between the two objectives was analyzed in the light of Pareto-optimal solutions. Through the optimization, the structural safety and aerodynamic performance of the centrifugal compressor were increased.

• 한국식품위생안전성학회지
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• 제12권2호
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• pp.160-174
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• 1997

Progress in commercialization of the irradiation process, greater international trade in irradiated food, differing regulations relating to use of the technology in many countries, and consumer demand for clear labeling of irradiated food highlighted the need for tests that could be applied to the food itself. Scientists have had to focus on identifying and isolating the minute changes caused in the component food molecules by the process. A number of investigators have reviewed the changes occurring in food after irradiation, detecting and measuring the effects of irradiation. The Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture organised a coordinated program on analytical detection methods in irradiation treatment of food (ADMIT) which promoted cooperation in this area and sponsored collaborative testing of some of the most promising methods.

• 한국유기농업학회지
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• 제12권1호
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• pp.67-80
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• 2004

Farm economy is getting worse because of the free trade trends in agriculture sector and unreasonable application of market economy principles to agricultural products. And The worldwide issues of environmental pollution as well as want of food, water and energy make human future be anxious. In addition, consumers raise questions in argument about safety of foods produced by traditional farming or imported. So I propose the urban-rural living community movement(URLCM) as an alternative plan for sustainable domestic agriculture. URLCM based on environmentally friendly agriculture and community consciousness will be able to solve many of present issues on agriculture and rural society through incessant interchanges between urban and rural community. This URLCM has to be basically founded on principles of symbiosis-coexistence and life circulation. So those that have to be driven forward arc organizing producers and consumer cooperatives, making environmentally friendly rural region and products, combining with consumer cooperatives, training the participants and so forth.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2006년도 춘계공동학술대회
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• pp.471-484
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• 2006

The focus of analysis is effect on Non-electrical Machinery and Equipment of Macroeconomic variables through long-term and short-term periods. Also, this paper is related with implication on steady growth possibility of Non-electrical Machinery and Equipment. The period of variables is from 1985 to April in 2005. In case of not-available data is treated as missing figures. As spatial scope, these data are Non-electrical Machinery and Equipment on the basis of KSIC. In case of items, it composes MTI 1&3 digit of Korea International Trade Association (KITA), on the basis of HSK & classification of Korea Machinery industries. According to Granger causality test, yield of Cooperate Bond and export amount of Machinery have a meaning at statistical Confidence level of 10%. In case of index of the unit cost of export and export amount of Machinery, they have an interactive Granger cause. In yen dollar exchange rate and export amount of Machinery, former variable gives an unilateral Granger cause to latter that.

• 대한안전경영과학회지
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• 제2권4호
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• pp.165-176
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• 2000

Broadband networks are designed to support a wide variety of services with different traffic characteristics and demands for Quality of Services. Bandwidth allocation methods can be classified into two major categories： static and dynamic. In static allocation, bandwidth is allocated only at call setup time and the allocated bandwidth is maintained during a session. In dynamic allocation, the allocated bandwidth is negotiated during a session. The purpose of this paper is to develop policies for deciding and for adjusting the amount of bandwidth requested for a best effort connection over such as ATM networks.. This method is to develop such policies that a good trade off between utilization and latency using cell delay variation to the forecast the incoming traffic in the next period. The performances of the different polices are compared by simulations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전력기술부문
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• pp.140-143
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• 2001

As global trade system transferred GATT into WTO, the harmonization of technological standards, certification, construction, testing is the trend of world. This drift is based on WTO / TBT agreement coming. In effect after 12th, April, 1979. For Korea, the distribution system has a strong resemblance to American system so that engineers are confused in adopting standards. IEC60364 and NEC are in part similar but unconvertible because IEC 60364 originated from Europe while NEC originated from USA. This thesis deals with the fundamental elements of electrical safety system with comparing IEC 60364 with NEC. It serves as a guide how to apply standards when engineers select electrical installations.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.133-134
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• 2006

Recently, despite of the effects of international Coordination and cooperation to prevent piracy, piracy is on an increasing trend every year. Such circumstances may have a bad effect on the sound development of world economy by means of trade in sea as well as treat to the safety of crews and safe operation of ships. Finally, Modern maritime piracy has become one of the major threats to safety at sea. We having Cargo-owners or Ship-owners attacked by piracy, it causes enormous economic losses. Therefore, Ship-owners and Cargo-owners insure Cargo Insurance, Hull Insurance and P&I Insurance to indemnity of losses which is caused by piracy. The Purpose of this paper was to explain the losses caused by piracy and studying the limits of the possibility of indemnity in the Cargo Insurance, Hull Insurance and P&I Insurance.

• 해양환경안전학회지
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• 제13권1호
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• pp.47-54
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• 2007

2001년 9월 11일 World trade center 테러이후, 미국세관 및 국경 경비대는 미국에 있는 모든 컨테이너 터미널에 inspection station을 설치하였다. 이 인스펙션은 container의 추가적인 지연을 직 간접적으로 유발하고 있다. 이에 본 연구는 이 지연을 분석하기위하여 대기이론을 이용하여 방법론적 연구를 제시하였다.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2000년도 추계학술발표논문집
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• pp.131-134
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• 2000

Broadband networks are designed to support a wide variety of services with different traffic characteristics and demands for Quality of Services. Bandwidth allocation methods can be classified into two major categories: static and dynamic. In static allocation, bandwidth is allocated only at call setup time and the allocated bandwidth is maintained during a session. In dynamic allocation, the allocated bandwidth is negotiated during a session. The purpose of this paper is to develop policies for deciding and for adjusting the amount of bandwidth requested for a best effort connection over such as ATM networks. This method is to develop such policies that a good trade off between utilization and latency using cell delay variation to the forecast the incoming traffic in the next period. The performances of the different polices are compared by simulations.

• 대한안전경영과학회지
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• 제8권1호
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• pp.181-194
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• 2006

Economic and political barriers in Northeast Asia including Korea have been eliminated gradually. As results of economic relations are more active in this region. The administration of physical distribution tightened circulation- cost down. This is one of the most important facts to develop world economy. Distribution in China is expected to grow quantitatively and continuously. China is just out of planned economic system. Therefore, it is expected that foreign affiliated firms will take a fierce competition for the next $1\sim2$ years. This study investigates Korea-China trade and distribution index with analysis and expectation of China market. The study analyzes the business conditions, faced problems and differentiated strategies of foreign affiliated firms. Be based on those, it is researched how domestic companies will make strategies to start China successfully.