• Korean Journal of Hydrosciences
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• v.8
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• pp.31-40
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• 1997

Flow carrying capacity of water distribution systems is getting reduced by deterioration of pipes in the systems. The objective of this paper is to present a managerial decision-making model for the rehabilitation of water distribution systems with a mininum cost. The decisions made by the model also satisfy the requirements for discharge and pressure at demanding nodes in the systems. Replacement cost, pipe break repair cost, and pumping cost are considered in the economic evaluation of the decision along with the break rate and the interest rate to determine the optimal replacement time for each pipe. Then, the hydraulic integrity of the water distribution system is checked for the decision by a pipe network simulator, KYPIPE, if discharge and pressure requirements are satisfied. In case the system does not satisfy the hydraulic requirements, the decision made for the optimal replacement time is revised until the requirments are satisfied. The model is well applied to an existing water distribution system, the Seoul Metropolitan Water Supply System (1st Phase). The results show that the decisions for the replacement time determined by the economic analysis are accepted as optimal and hydraulic integrity of the system is in good condition.

• Journal of Korea Port Economic Association
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• v.21 no.1
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• pp.1-21
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• 2005

It has been more recent trends in container trade to make bogger ship from shipowners that many more parties concerned are getting involved. Well, it is natural to swift these situations if we have looked into container trade market in present time, which a lot of trade volumes has increased in world economy. Thus, supply side of shipping service needs to employ more capacity in the shipping market, then newbuilding may be compulsory options, that is deployment of larger ships. To cope with market situations as able shipowner, some alternatives can be also adopted, such as newbuilding, chartering and securing the space by strategic alliance. But whatever he does, shipowner has to keep in mind to prepare for the future. This is much more important factor considered to make investment decision in case of newbuilding and then he can make more efficient decision as well. However, there has been a little problems arisen due to larger ship employed on the trade route, which is linked with seaport, shipping companies and freight rates as well. Although shipowner decides to build new larger vessel as one of corporate strategic decision, there are many questions to be considered in advance. Therefore, in order to take more efficient decision, shipowner has to take into an account various situations surrounded, and then it can lead truly thoughtful decision making process.

• Journal of Biosystems Engineering
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• v.25 no.5
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• pp.391-398
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• 2000

This study was performed to analyze the holding pace and decision factors of tractor in Korea and Japan, which probably should be used for making master plan of agricultural mechanization. The logistic function is used for holding pace estimation of tractor, and log-log function for analysis of decision factors. The results of this study are as follows: First, the increasing rate of the total amount of holding tractor power in Korea has been over that in Japan during 1980∼、94 which is now, however, under Japan. So, it could be forecasted that the per tractor holding power in Japan will increase continuously, and will be over 30PS in the short run. Second, the most important one of decision factors to support tractor demand is agricultural income in Korea, but on the other hand Non-Agricultural Income in Japan. From these, the fast increase of total amount of holding power of tractor in Korea could not expected, because Korea Agriculture has some difficulties to increase Agricultural Income. There are differences on the holding pace and decision factors of tractor between Korea and Japan, therefore, the plan of agricultural mechanization should be made in accordance with self-features.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.17 no.31
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• pp.73-80
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• 1994

Sequentiality in decision making is an inherent characteristic of the R&D Process, Conceptual changes are noted during the Course of the Project which represent a continuous improvement in the quality of the data available during the various project stages. In this paper, Eight characteristic types of project evaluation models have been developed economic index models, portfolio models, decision theory models, risk analysis models, frontier models, scoring models, profile models and checklists. Each of these will be critically reviewed and appraised.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.2 s.6
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• pp.101-113
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• 1995

In pipeline planning, the systematic and reasonal management of topographical and spatial data are needed in order to omprove the availibilities for data analysis and the effective combinations of spatial informations. According to that fact, DBMS (Database Management System) and DSS(Decision making Support System) have to be developed for the planning of water supply system Also, the economic selection for harmonious delivery of water to target area, since the alternatives of pre-designed pipeline are influenced by hydraulic stability and geographic characteristics. In this study, GIS technique for water supply planning and management which stores graphic features and attributes as digital data sets is considered and engineering application programs are integrated for effective planning of water supply system. Decision making support system based on analyzing technical, Social and economical aspects is developed for the extension of water supply facilities and pipeline configurations. Especially, Hydraulic, land-use and economic influences are considered as important factors for the purpose of developing the system. Hydraulic analysis program(SAPID) for pipeline flow which is already developed in Water Resources Research Institute and economic analysis program(ECOVEL) are integrated with GIS for resonable decision making. Every possible aspects in pipeline planning for water supply is reviewed and the applicabilities of developed system into the field are evaluated.

• Korean Journal of Social Welfare
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• v.57 no.4
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• pp.5-33
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• 2005

In order to examine the causes of the social policy changes in Korea during the late of 1990s, this study tries to compare the social policy decision-making structure between Kim Yong-Sam Government and Kim Dae-Jung Government. This study applies policy network analysis method which measures the relation and power structures of policy actors and as a result shows the characteristics of the policy making structure. Analysing the 6 policy domains and 52 policy events, this study finds that the importance and location of veto points which were created by the social policy decision processes have changed. In Korea, social policy decision processes have been produced power structures in which Ministry of Finance and Economic Planning Board have played a decisive role. In result, these executives can have controlled policy making processes and had veto power, i. e. veto points in policy decision-making structure. But, during Kim Dae-Jung government, accountability issues of financial crisis and reorganization of ministries have changed the importance and location of veto points. Pro-welfare groups of civil society got a chance to penetrate policy decision-making structure during that time. This study argues that these changes of policy decision-making structure may be associated with the social policy changes in Korea during the late of 1990s.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.431-439
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• 2016

Urban regeneration projects involve various stakeholders, which result in decision making processes that require long periods of time and cause many conflicts. This study aims to identify important factors in decision making for promoting an urban regeneration project. The analysis results utilizing AHP are as follows: Firstly, the analysis results identify the main considerations in the process of promoting urban regeneration projects as residents' opinion(0.393), involvement of local government(0.231), opinions of related experts(0.206) and master plan(0.169). Secondly, the key drivers of stakeholders' qualitative decision making were found to include sustainability(0.325), economic feasibility(0.277), ease of project implementation(0.232) and equity(0.166). Lastly, meaningful differences in the relative importance of key aspects of decision making were identified when respondents were grouped according to being aware or not aware of the urban regeneration project, as well as living on or living off the project site. The results of this study can be used to implement successful urban regeneration projects in the future.

• International Journal of Highway Engineering
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• v.15 no.3
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• pp.169-176
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• 2013

PURPOSES : Lots of criticism such as over/duplication investment, inconsistency of the policies among local governments and national plans etc. has been aroused due to the policy of supply-driven construction for transportation facilities. Recently, according to the environmental-friendly transportation policy, the investment of railroad has been expanded gradually, however the duplication with existing road facility makes it difficult to construct railroad. Thus it is necessary to evaluate the interrelationship between new project and existing facilities in the planning stage. However the method and the criteria for analyzing the duplication and over-investment of projects are not established in the manual, thus the feasibility of these projects are carried out from the economic point of view. METHODS: First, It reviewed about interrelationship criteria(domestic, overseas) and proposed implications and this study directions. Next, It developed the methods of evaluating independency, competitiveness and complementarity. RESULTS : In this study, the methods of evaluating independency, competitiveness and complementarity etc. are suggested to analyze the interrelationship between transportation facilities. The case study was carried out to examine the applicability of the methods. CONCLUSIONS: The methods raise rationality of decision-making compared to existing one. In the future, these methods are introduced into the manual of pre-feasibility study and feasibility study, more efficient decision-making and investment are expected.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.2
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• pp.81-90
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• 2013

A study on the flow-structure characteristics of marine 3/2WAY pneumatic valve is essential for optimizing the performance of ship engines. It is important that the valve has desirable safety factor and reduced weight from safety and economic point of view. In this paper, flow-structure characteristics of pneumatic valve is obtained by being optimized based on the proper design criteria. The air with the pressure of 30 bar is the working fluid which is made to fill in the tack in short time. This time is defined as the filling time. On optimum design by considering the flow-structure characteristics, the approach is based on (1) the mathematical formulation of design decisions using the compromise decision-making method, and (2) the approximation technique of response surfaces. The methodology is demonstrated as the multi-objective optimization tool to improve the performance of marine 3/2WAY pneumatic valve.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.33 no.12
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• pp.13-18
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• 2017

Recently, the form of traditional families has been disintegrated due to low birthrate, aging, declining marriage, individualism, etc. In particular, the number of single households has increased due to the shift to a low-growth advanced economic structure, women's social participation, diversification of lifestyles, and so on. According to the National Statistical Office, the number of single households living alone by 2015 is estimated to be about 5,060,000 households, which is estimated to account for 34.3% of all households, which has greatly increased compared with about 660,000 (6.9%) in 1985. However, the housing market has not been able to respond to such social changes. Therefore, in this research, we presented a plan to visualize the public data of single household in Seoul city and prediction result of occupancy shape for the purpose of supporting decision making of single household consumers.