• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.9
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• pp.1185-1194
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• 2000

The characteristics of intake port flow and engine performance with swirl ratio variance in a turbocharged D.I. diesel engine were studied in this paper. The intake port flow is important factor which have influence on the engine performance and exhaust emission because the properties in the injected fuel depend on the combustion characteristics. Through these experiments it can be expected to satisfy performance and emission by optimizing the main parameters; the swirl ratio of intake port, injection timing and compression ratio. The swirl ratio for ports was modified by hand-working and measured by impulse swirl meter. For the effects on performance and emission, the brake torque and brake specific fuel consumption were measured by engine dynamometer, NOx and smoke were measured by gas analyzer and smoke meter. The results of steady flow test are as follows; as the valve eccentricity ratio are closed to cylinder wall, the flow coefficient and swirl intensity are increased. Also we realized that there is a trade-off that the increase of swirl ratio decreases mean flow coefficient and increases the Gulf factor. And the optimum parameters to meet performance and emission through engine test are as follows; the swirl ratio 2.43, injection timing BTDC 13oCA and compression ratio 15.5.

• Journal of Korea Water Resources Association
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• v.36 no.4
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• pp.547-559
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• 2003

In this study, a mathematical model is developed for sewer rehabilitation planning by considering cost and inflow/infiltration. A sewer rehabilitation planning model is required to decide the economic life of the sewer by considering trade-off between cost and inflow/infiltration. And it is required to find the optimal rehabilitation timing, according to the cost effectiveness of each sewer rehabilitation within the budget. To solve the problem, we formulated a multiple objective mixed integer programming(MOMIP) model based on network flow optimization. The network is composed of state nodes and arcs. The state nodes represent the remaining life and the arcs represent the change of the state. The model considers multiple objectives which are cost minimization and minimization of inflow/infiltration. Using the multiple objective optimization, the trade-off between the cost and inflow/infiltration is presented to the planner so that a proper sewer rehabilitation plan can be selected.

• Journal of the Korean Institute of Navigation
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• v.19 no.1
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• pp.49-69
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• 1995

What is the national competitive power\ulcorner What are the determinants of national competitive advantage\ulcorner In order to find these problems, this study was initiated theoretically through the international trade theory and international managerial strategic theory. The flow of studies, in connection with these competitive advantage, come into industries competitive advantage from national competitive advantage. It is understood that the flow of studies is based on the change of paradigm about the international industry environment. Today, the international industry environment has been changed into vigorous situation with the new trade system such as globalization, UR negotiation, WTO system instead of GATT. Among these environments, all enterprises in any industries should try to enhance their benefit, income profits and develop their management strategy, because it is essential for them to keep and make a profit in order to be competitive against all other rivaling enterprises. According to researchers and the ages of history, the concept and determinants of competitive advantage have been dissimiliar as followings. 1) Theory of absolute advantage : Absolute Product Cost. 2) Theory of comparative advantage : Comparative Product Cost. 3) Theory of reciprocal demand : the Reciprocal Demand Structure. 4) Theory of Hechsher-Ohlin : Factor Endowment. 5) Paradox of Leontief : the Quality of Factor Endowment. 6) Theory of technological gap : R & D. 7) Technological gap model : The Technological Gap. 8) Theory of the product life cycle : Product Life Cycle. 9) Christensen's study : Firm's character & manager's character. 10) Monopolistic Advantage Theories : Monopolistic Advantage 11) Electic theory : Ownership, location and internalization specific advantages. 12) Theory of value chain : Cost advantage, Differentiation, Focus. However all these theories have the limit of illustration regarding today's competitive situation, the Porter's theory shows well the determinants of competitive advantage with competitive strategy. Therefore, the analysis of the competitive advantage for maritime industry should be studied by the determinants of competitive advantage of nations

• Journal of the Economic Geographical Society of Korea
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• v.13 no.3
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• pp.457-469
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• 2010

The study aims to estimate interregional trade coefficient of service industry using the gravity model. The gravity model has been widely used for prediction of the level of human interaction between two regions which is positively related to attraction of them and negatively related to the distance between them. To apply the gravity model for explaining the interregional trade flow of service industry, the choice of proper proxy variables which represent a dependent variable and independent variables is most important. However, the literature shows that there are few studies on this issue. Four models concerned to the choice of proxy variables are considered. Finally, this paper employs the least-squares regression analysis to test the model's goodness-of-fit, and suggests the most appropriate model based on the result from the analysis. The result shows that the interregional trade of service industry in regional input-output table developed by The Bank of Korea is desirable as a dependent variable, the service industry output of export region, the population of import region, and the spatial distance between regions are desirable as independent variables.

• Journal of Evidence-Based Herbal Medicine
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• v.1 no.2
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• pp.17-26
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• 2008

Nowadays the flow of international trade is that there seems to appear economic block significantly because most countries contract FTAs, so our market condition is changing to a severe competitive situation. Korea which has 70% of foreign dependence of trade must get involved in regionalism, and also actively promote FTA more than any other countries. FTA on February in 2006, the pharmaceutical industry are anxious. The pharmaceutical industry in Korea has recently come to a crisis that it is hard to expect a growth due to structure of profit and a change for the worse of management. If Korea-U.S. FTA are contracted in this kind of situation, domestic pharmaceutical companies will be at stake. We can anticipate that FTA with the country that has a strong competitive power like U.S. affect negatively on pharmaceutical industry, because the industry doesn't have enough self-competitiveness. Considering this kind of surroundings, we need to present the policy to enhance competitiveness for damage limitation on pharmaceutical industry by Korea-U.S. FTA. Under this background, this research has groped for a direction to strengthen the competitiveness to develop pharmaceutical industry in quality. The competitive enhancement plan is presented which is divided into the government policy part, the R&D part, and the management part. Although Korea-U.S. FTA is analyzed to wither the pharmaceutical industry, it would be thought that it is a good chance to upgrade domestic pharmaceutical industry if we make the best use of it, and also to make in roads into foreign market.

• Industrial Engineering and Management Systems
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• v.12 no.4
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• pp.351-358
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• 2013

This paper proposes a multiobjective model describing the trade-offs involved in selecting the locations of drop-off boxes for collecting used products and transporting these products to designated locations. We assume the following reverse flow of used products. Owners of used products (cellular phones, digital cameras, ink cartridges, etc.) take them to the nearest drop-off box when the distance is reasonably short. We also assume that owners living closer to drop-off boxes dispose of more used products than do owners living farther from drop-off boxes. Different types of used products are collected, with each type requiring its own drop-off box. A transportation destination for each product is specified. Three objectives are considered: maximizing the volume of used products collected at drop-off boxes; minimizing the cost of transporting collected products to designated locations; and minimizing the cost of allocating space for drop-off boxes. We formulate the above model as a multiobjective integer programming problem and generate the corresponding set of Pareto optimal solutions. We apply the model to an area using population data for Chofu City, Tokyo, Japan, and analyze the trade-offs between the objectives.

• Journal of Korea Port Economic Association
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• v.21 no.4
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• pp.183-207
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• 2005

Global firms are seeking to implement their global logistics strategies in two ways: the use of centralized inventories and/or postponement of final assembly. These strategies stress the importance of regional logistics centers. In most cases, regional logistics centers are located in or near ports so that changing demands can be met with economy, reliability and flexibility, The port can profit not only from the activities of logistics center itself, but also the increasing flow of cargo through the logistics center. A number of ports respond to this trend by shifting their emphasis from traditional cargo-handling services to value-added services. This paper presents guidelines drawn from the best practices of ports to be successful logistics centers to provide many aspects of value-added logistics services. These include: Effective Planning and Development of Logistics Centers; Institutional Incentive Scheme; Development of Free Trade Zones; Financing Infrastructure related to Logistics Centers; Developing Logistics Service Providers and Logistics Professionals; Development of Information Technology; and Regulatory and Administrative Issues. These guidelines will help managers of ports and policy makers of governments in the East Asian region learn to recognize, analyze and adopt the best practices for use.

• The Journal of Industrial Distribution & Business
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• v.8 no.2
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• pp.5-10
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• 2017

Purpose - The purpose of this paper was to analyze the Chinese government's announcement of the RMB's appreciation on July 1, 2010, and its aim was to ascertain whether the appreciation has affected Chinese export prices by empirically measuring the degree of the exchange rate pass-tough on those prices. Research design, data, and methodology - Using 73 HS trade categories with cross-industry and time-series data, the panel estimation of a fixed-effects model has been applied to measure the degree and stability of any exchange rate pass-through effects. The estimation results show that the export prices of most trade categories were affected by the exchange rate changes. The pass-through effect was generally small, at about -0.485, and statistically significant in most export prices. Results - The empirical results indicate that China would lose its advantage and competitiveness in export if the RMB were appreciated continuously and rapidly because its export goods would no longer operate under strong monopolistic competition. Conclusions - The implications for China's exchange rate policy suggest that it would be better for the RMB to appreciate slowly and gradually rather than radically. It is clear that it would be allow the capital free flow in Chinese overall economic interest to reduce the continuous appreciation pressure on the currency and pave the way for improvements in export distribution competitiveness.

• Journal of the Korean Geographical Society
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• v.46 no.6
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• pp.751-766
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• 2011

This study aims to grasp the hierarchy in the influence areas of port by the intensity of freight shipments and to seek the activating methods for the increase of export and import volumes of Pyeongtaek and Dangjin port. Pyeongtaek and Dangjin port whose major import and export freights are natural gas and automobile, were constructed for the increasing trade with People's Republic of China. This port is expanding the influence in the hinterland and foreland of the port, but core influence area of Pyeongtaek and Dangjin port is rich in trade volume within the radius of 70km. To become international as well as national ports, Pyeongtaek and Dangjin is required to execute the active policy to receive many-sideness of sea route and the recognition of freight holders, forwarders and ship companies in many regions.

• Acta Via Serica
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• v.2 no.1
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• pp.109-120
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• 2017

The city of Basra, established on the shore of Basra Bay in the south of modern Iraq, played an important role in agriculture and trade for centuries, with its geography and its position where two great rivers of Mesopotamia flow. Before being established with its current name by the Muslim Arabs, the city was known as Teredon in the Chaldean period and VehiŞtebad ErdeŞir in the Sasanid period. It was reestablished with the name Basra in the early period of Islam by Arabs between Hijri 14-16 (635-637 CE). Afterward, the city became one of the most important centers of trade, science and thought; had a perfect cultural diversity; and hosted important schools of Arabic language and thought for centuries. Besides the commercial effects of its being a transfer point on the axis of Europe, Mesopotamia, Iran, and India, the schools of thought which emerged here were affected by this mobility. In this paper, we try to reveal the philosophical-religious approach which the Ikhwan al-Safa school of thought in Basra, one of the most important cities of the Silk Road, created in parallel with the characteristics of this city. Shiite Ismaili beliefs and thoughts in the region and its characteristics which feed different religions and traditions emerging from Egypt and with the scientific approach of Greek thought; with Indian-Iranian teachings that merge Greek thought and Neoplatonic philosophy, give us the summary of Silk Road civilizations.