• Transactions of the Korean Society of Automotive Engineers
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• v.1 no.2
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• pp.1-16
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• 1993

It is widely recognized that exhaust emissions, fuel economy and engine torque are affected by engine temperature, and logic would suggest that a cooling system offering a better compromise of engine temperature would improve both overall engine performance and economy. Author measured coolant temperature of some parts and flow rate which are necessary to heat transfer in a engine. And Author determined parameters necessary for the optimum design of a thermostat to keep the best engine performance ; determined the optimum operating temperature of electric cooling fan. A summary of this study is followed. 1. Study of the effects of cooling condition to combustion character in a engine. 2. Analyze of heat transfer surrounding engine cylinders. 3. Study of the effects of cooling character to engine heat rejection, determination of the optimum collant temperature for keeping the optimum engine performance and determination of the optimum design of a thermostat for keeping that temperature.

• Electronics and Telecommunications Trends
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• v.37 no.5
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• pp.1-10
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• 2022

Digital trade rules are crucial in supporting the digital economy as the rules effectively reduce unnecessary trade barriers. This study introduces various approaches that major countries take regarding digital trade policies and rules. Comprehensive and Progressive Agreement for Trans-Pacific Partnership has introduced comprehensive rules on e-commerce, including binding articles on the free flow of information, location of computing facilities, and source code. More recent e-commerce provisions or digital trade agreements cover wider range of issues, from cyber security, artificial intelligence, and data innovation to electronic invoicing and payments. Multilateral negotiations on digital trade rules, including the World Trade Organization E-commerce Joint Statement Initiatives and Indo-Pacific Economic Framework, are in progress. Thus, countries involved are expected to respond to new digital trade issues with long-term strategies considering domestic policy objectives.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.2
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• pp.38-49
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• 2000

A diesel engine has been studied for many years to improve fuel economy and to reduce emissions as important factors governing the emission performance of diesel engines. This study addresses to swirl effects on combustion characteristics in a large diesel engine. The transport equations of flows and chemical reactions are given for fully compressible fluid. The simulations have been done for compression and expansion strokes and the results are given at several crank angles which are the angles at just before injection start, TDC, ATDC 90 and just before exhaust valve open. The results show that the strength of the swirl flow makes many effects on burning fuel and forming emissions.

• Nuclear Engineering and Technology
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• v.45 no.5
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• pp.665-674
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• 2013

This paper presents the development and validation methods of the FUTURE (FUel cycle analysis Tool for nUcleaR Energy) code, which was developed for a dynamic material flow evaluation and economic analysis of the nuclear fuel cycle. This code enables an evaluation of a nuclear material flow and its economy for diverse nuclear fuel cycles based on a predictable scenario. The most notable virtue of this FUTURE code, which was developed using C# and MICROSOFT SQL DBMS, is that a program user can design a nuclear fuel cycle process easily using a standard process on the canvas screen through a drag-and-drop method. From the user's point of view, this code is very easy to use thanks to its high flexibility. In addition, the new code also enables the maintenance of data integrity by constructing a database environment of the results of the nuclear fuel cycle analyses.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.735-745
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• 2013

Tour industry has been growing with increasing of people leisure time quantitatively as well as qualitatively. Especially, region tourist industry shows rapid growth because of the development of transportation and communication. Tourist contents that representing the region have been developing briskly. However there are many nominal tourist contents have just region differentiation with same attribute and composition. It has to be consider about tourist first not a contents provider or a developer. To be memorable tourist contents and to connect to consumption, understanding about tourist is needed. So 'Experience' will be standards when tourist contents is planned. In that sense, experience 4factors from Experience Economy and Challenge-skill model from Flow will be frames for giving shape to develop tourist contents. Experience 4factors from Experience Economy suggests 4factors for the superb enjoyment to tourists, and Challenge-skill model from Flow proposes balanced contents for understanding tourists. They will contribute to suggest planning frames for sustainable tourist contents and it lead to tourists' reinstation.

• Journal of Environmental Policy
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• v.12 no.1
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• pp.125-153
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• 2013

The purpose of this article is to measure sustainability of countries based on material flow approach by connecting fossil fuel vs. economy, and fossil fuel vs. environment, respectively. The focus of the article is to confirm where each country concentrates more between economic growth and environment. Even though most of countries exclaimed the growth harmonized between economy and environment, the empirical results proved that they had weight on economic growth over environment. Of three country groups, the sustainability in OECD countries was the lowest, whereas that of low income countries was the highest. It has been known that the main offenders of global warming are developing countries and backward countries, but emission of greenhouse gas per capita in OECD countries was higher and as a result, their sustainability was much lower than those of other countries. Accordingly, because the OECD countries have more responsibility for the emission of greenhouse gas, it is necessary that they have to bear a larger portion of emission reduction.

• Journal of the Economic Geographical Society of Korea
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• v.1 no.1
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• pp.113-135
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• 1998

There have been several research methodologies to measure the impacts of tourism development on the regional economy, which include input-output analysis, income multiplier analysis, labor creation effect analysis, etc. Most of these are based on regional economic indices using secondary data for medium to large regional units. This study tests the possibility of adopting tourist money now analysis, which encompasses a series of money flows beginning with tourists'payment for room, board and shopping, followed by tourist companies'expenditure for material and service purchase, wage, utilities, rent, tax and so forth, and by tourism workers'expenses for living and savings. This method makes it possible to reveal the amount and geographical extent of tourist money flow and draws some meaningful regional economic figures. Case studies of three torist developing areas show that it is utilized for impact studies for small scale areas.

• International Journal of Automotive Technology
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• v.6 no.1
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• pp.1-8
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• 2005

Recently, the HSDI (High Speed Direct Injection) diesel engine has been spotlighted as a next generation engine because it has a good potential for high thermal efficiency and fuel economy. This study was carried out to investigate the in-cylinder flow characteristics generated in a HSDI diesel engine with a 4-valve type cylinder head. The four kinds of cylinder head were manufactured to elucidate the effect of intake port geometry on the in-cylinder flow characteristics. The steady flow characteristics such as coefficient of flow rate $(C_{f})$, swirl ratio (Rs), and mass flow rate (m,) were measured by the steady flow test rig and the unsteady flow velocity within a cylinder was measured by PIV. In addition, the in-cylinder flow patterns were visualized by the visualization experiment and these results were compared with simulation results calculated by the commercial CFD code. The steady flow test results indicated that the mass flow rate of the cylinder head with a short distance between the two intake ports is $13\%$ more than that of the other head. However, the non-dimensional swirl ratio is decreased by approximately $15\%$. As a result of in-cylinder flow characteristics obtained by PIV and CFD calculation, we found that the swirl center was eccentric from the cylinder center and the position of swirl center was changed with crank angle. As the piston moves to near the TDC, the swirl center corresponded to the cylinder center and the velocity distribution became uniform. In addition, the results of the calculation are in good agreement with the experimental results.

• Journal of Korean Port Research
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• v.6 no.1
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• pp.93-110
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• 1992

The most change in this century is supposed to be declination of ideology, and block of world economy. Addition to down full of cold war atmosphere around Northeast Asia, not only economic and social mood in this region is dramatically changed, but also it gave birth to the block of Northeast economy that accerlated new hub of world economy. According to dramatic change of economic surroundings the dynamic potential of growth in this region will be guided to enlarge inter-regional trade and increase volume of trade, thus suggests to grow steadily transportation. cargos in this region will have to arrange the system of delivery and inner transportation, accessary facilities, inter-regional harbors if North America and EC has connected easily. As have accerlated GATT and UR represented multilateralism and regionalism, it has regulated to increase trades of region due to relief of the trade barrier through specific areas has agreed with separately. The flow of regionalism of world economy has appeared to realize EC and NAFTA centered U.S.A, and also has presented to free trade region or one-size market agreement in Asia as APEC, EAEG in Malaysia, and etc. In defense to this block and internationalism of world economy, Pusan has to come forward to the hub of Northeast others has proposed a project to dominate the Northeast, Economy Association Agreement as Far East comprehensive development project in USSR, Hunchun development project in NK, and East Sea development project in PRC, Niigate regional development in Japan, Duman River development project in NK, and East Sea development project in Korea. As this exercise has proceed, Pusan also have arranged development strategy definitely and prepared provisions systematically. Engaging to participate center of delivery system is meant to be completed complex functions, namely the transfer storage processing & assembly function of international commodity. Pusan has ability to be terminal point of TSR. it had been connected to EC as the biggest economy block and TKR as complex transportation root to Far East, it would be the center of inground and seabase delivery terminal to Rotterdom as the biggest container pier and major piers to North-East and South East Asia. In order to provide a Role of 21 century's internationalization, Pusan has appealed to participate in management information research and development connected to Pohang-Ulsan-Changwon-Masan, and has utilized efficiently the resources such as man, material, money and information.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.3
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• pp.120-130
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• 2001

We present an approach to parallelizing optimal power flow that is suitable for distributed implementation and is applicable to very large interconnected power systems. This approach can be used by utilities to optimize economy interchange without disclosing details of their operating costs to competitors. Recently, it is becoming necessary to incorporate contingency constraints into the formulation, and more rapid updates of telemetered data and faster solution time are becoming important to better track changes in the system. This concern led to a research to develop an efficient algorithm for a distributed optimal power flow based on the Auxiliary Problem Principle and to study the convergence rate improvement of the distributed algorithm. The objective of this paper is to find a set of control parameters with which the Auxiliary Problem Principle (Algorithm - APP) can be best implemented in solving optimal power flow problems. We employed several IEEE Reliability Test Systems, and Korea Power System to demonstrate the alternative parameter sets.