• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.6
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• pp.1375-1383
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• 1994

The water distribution system problem consists of finding a minimum cost system design subject to hydraulic and operational constraints. Since the municipal water distribution system problem is nonconvex with multiple local minima, classical optimization methods find a local optimum. An outer flow search - inner optimization procedure is proposed for choosing a better local minimum for the water distribution systems. The pipe network is judiciously subjected to the outer search scheme which chooses alternative flow configurations to find an optimal flow division among pipes. Because the problem is nonconvex, a global search scheme called Stochastic Probing method is employed to permit a local optimum seeking method to migrate among various local minima. A local minimizer is employed for the design of least cost diameters for pipes in the network. The algorithm can also be employed for optimal design of parallel expansion of existing networks. In this paper one municipal water distribution system is considered. The optimal solutions thus found have significantly smaller costs than the ones reported previously by other researchers.

• Journal of the Korea Safety Management & Science
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• v.15 no.1
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• pp.77-85
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• 2013

In the location science, environmental effect becomes a new main consideration for site selection. For the unwanted facility location selection, decision makers should consider the cost of resolving the environmental conflict. We introduced the negative influence cost for the facility which was inversely proportional to distance between the facility and residents. An unwanted facility location problem was suggested to minimize the sum of the negative influence cost and the transportation cost. The objective cost function was analyzed as nonlinear type and was neither convex nor concave. Three GRASP (Greedy Randomized adaptive Search Procedure) methods as like Random_GRASP, Epsilon_GRASP and GRID_GRASP were developed to solve the unwanted facility location problem. The Newton's method for nonlinear optimization problem was used for local search in GRASP. Experimental results showed that quality of solution of the GRID_GRASP was better than those of Random_GRASP and Epsilon_GRASP. The calculation time of Random_GRASP and Epsilon_GRASP were faster than that of Grid_GRASP.

• Journal of Environmental Science International
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• v.27 no.5
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• pp.281-289
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• 2018

The Korean environmental impact assessment(EIA) system, and explored ways to improve it as a more efficient and viable institution relevant to the demand of our time and conditions in study. The first problem this study identified is found in the fact that the party to write up the assessment report is itself the business operator or the one who is planning to work out the business plan. This structure translates into placing an order with an agent for EIA report. The reporting job may br subcontracted to the agent at a cost far below the rate specified in the 'Standard for Estimate of Agency Fee for Environmental Impact Assessment.' This practice also causes the vicious circle of producing a report that is written to justify the project or business in question or it leads to rough-and ready and poor documentation to minimize the time required. Second, in order to achieve the goal of the plan or business, which is the target of EIA, the local residents tend to ve regarded as an obstacle. This means elimination of the local people from participating in the EIA or their opinion being frequently ignored. This is the seed of distrust and hostility that sometimes provoke disagreements or fierce conflicts. The first proposal to improve these problem is to improve the factors that cause poor documentation of the assessment report as well as improve the understanding of the EIA system. This study proposes the following measures for improvement. The agency cost for EIA should be paid by the business operator or a third party that can ensure faithful implementation of the payment. A system should be established to verify transparent estimation of the agency cost. In order to enhance the professional quality of EIA agents, there should be implementation of qualification test for industrial engineer of related engineers in addition to the current EIA Qualification Test. The second proposal for improvement is to improve the citizen participation process by instituting a legal framework to make clear the purpose of the briefing session for local residents, which is held as a procedure of EIA, and to ensure more positive publicity during the stage of listening to the opinion of the local community. For a smooth and rational communication process, a moderator and a communicator of opinion, as is the case in a public hearing, could be instituted to clearly get the purpose of the briefing session across to the residents and to help to carry out the explanation and Q & A sessions according to the categories of the opinion of the residents. At present, the notification of the public inspection of the draft of the assessment report and briefing session for the residents is made on the newspaper and internet network. But some people have difficulty with access to this method of announcement. A higher participation rate could be secured if a legal provision is added to specify putting up placards in specific places such as the entrance to the place for the briefing session for residents or the building of administrative agencies of the area concerned.

• Journal of environmental and Sanitary engineering
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• v.23 no.3
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• pp.59-71
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• 2008

In this study, we intend to present the uncontrolled landfill maintenance plans by diversely reviewing the operating conditions of landfill and environmental effects and economical issues resulted from the operation of landfill for the purpose of suggesting the optimal maintenance plans applicable to the uncontrolled landfill and unused landfill located in Korea. We perform the basic and precise surveys against three landfill sites showing the biggest problem out of 8 unsanitary landfills sites located in Y County. We compare and review the treatment plans prepared and operated by the N Landfill. The compared and reviewed results show that the local stabilization plan is more effective than the excavation and transfer treatment plan when considering the economic efficiency only. However, the excavation and transfer treatment plan is valid when considering the diverse elements. The G Landfill is operated with separated into living waste landfill section and construction waste landfill section. However, some landfill gas collection bores or holes are installed in its living waste landfill section, which has not been used for about 20 years, as a part of follow-up control. The element causing the environmental damage is considerably reduced in its living waste landfill section. However, the effort to keep the follow-up control through the local stabilization work is required. The landfill is under processing in the construction waste landfill section. However, most of buried wastes are the inorganic wastes such as waste materials and concrete, so the maintenance plan focused on the use of top land by installing the local stabilization facilities is considered as an effective plan. The landfill is under processing in the K Landfill. It seems to be difficult to maintain this landfill through the local stabilization. The excavation and transfer treatment plan to completely remove the potential environmental pollution source is considered as the valid plan.

• Journal of Information Technology Applications and Management
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• v.22 no.1
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• pp.131-152
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• 2015

Environmental differences across countries such as socio-cultural, political, economic, and technological differences require business strategies of multinational corporations to vary business practices across regions. Despite the keen awareness of the necessity for strategic adaptation to local context, IS management and strategy tend to remain similar across countries. One of the reasons is to maintain the stability and compatibility of information technology infrastructure. After a careful observation of retail business practice, this study finds IS strategy should also be highly responsive to the local context. This study shows how information resources including systems architecture, processes, human resources, and national context are interlinked together. Despite global excellence in general systems management, failure in such alignment can be a serious problem in extending competitive advantages across regions. This study aims to reveal issues to be taken care of in order to accomplish global technological alignment. Results of this study provide senior management with guidelines and a framework for aligning IT with regional strategic thrust that can improve local responsiveness of multinational companies.

• SUVANNABHUMI
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• v.9 no.1
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• pp.7-52
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• 2017

This paper analyzes the scholarly approaches to the problem of "local" vs. "cosmopolitan" in the context of the cultural transfers between South and Southeast Asia. Taking the "localization" paradigm advanced by Oliver Wolters as its pivot, it reviews the "externalist" and "autonomous" positions, and questions the hermeneutical validity of the fuzzy and self-explanatory category of "local." Having discussed the geo-environmental metaphors of "Monsoon Asia" and "Maritime Asia" as alternative paradigms to make justice to the complex dynamics of transregional interaction that shaped South and Southeast Asian societies, it briefly presents two case studies highlighting the tensions between the "local" and "cosmopolitan" approaches to the study of Old Javanese literature and Balinese Hinduism.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1299-1306
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• 2017

This paper presents a boundary tracking control of an agent. To this end, it is shown that the boundary tracking problem can be reformulated into a robust control of uncertain double integrator first. Then, a disturbance observer (DOB) based control is proposed solving the robust control problem. Unlike the existing results in the literature, the proposed DOB based control requires only the local position measurement of the boundary (not the gradient information). The performance of the proposed control is demonstrated for two cases: the measurement of the boundary is given in a continuous or discrete manner. Finally, it is shown that the proposed control can be used for environmental monitoring as well by showing that the agent follows a level curve of real environmental monitoring data.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.367-376
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• 2004

In urban area, thermal pollution associated with heat island phenomena is generally regarded to make urban life uncomfortable. To overcome this urban thermal pollution problem, urban planning with consideration of urban climate, represented by the concept of urban ventilation lane, is widely practiced in many countries. In this study, the prevailing wind ventilation lane of a local winds in Daegu during the warm climate season was investigated by using surface wind data and RAMS(Reasonal Atmospheric Model System) simulation. The domain of interest is the vicinity of Daegu metropolitan city(about 900 $km^{2})$ and its horizontal scale is about 30km. The simulations were conducted under the synoptic condition of late spring with the weak gradient wind and mostly clear sky. From the numerical simulations, the following two major conclusions were obtained: (1)The major wind passages of the local circulation wind generated by radiative cooling over the mountains(Mt. Palgong and Mt. Ap) are found. The winds blow down along the valley axis over the eastern part of the Daegu area as a gravity flow during nighttime. (2)After that time, the winds blow toward the western part of Daegu through the city center. As the result, the higher temperature region appears over the western part of Daegu metropolitan area.

• Journal of the Korean Society of Earth Science Education
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• v.4 no.1
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• pp.66-73
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• 2011

This study aims to compare and analyze the types of teaching-learning activities, themes and percentage of STS contents in the area of "The Earth and the Universe" in elementary science subject following the 7th Curriculum and 2007 Revised Curriculum, identifying how STS education has changed and their features. First, the number of pages where STS appears in the 2007 revised science textbook has increased over 10% compared to the that of the 7th curriculum. In particular, the number of pages in the 5th and 6th graders increased substantially to 15% and 34%, respectively. Second, as a result of analysis on components of STS, 'applications of science', 'local and community relevance', 'social problem and issues', 'evaluation concerned fir getting and using information' were obtained in the order named for the 7th curriculum; while 'applications of science', 'local and community relevance', 'career awareness' and 'social problem and issues' were obtained in the order named for 2007 revised curriculum. Third, with regard to the analysis on theme areas, the 7th curriculum was found to cover the theme on use of natural resources most frequently, followed by environmental problem, while 2007 revised curriculum to cover environmental problem and effects of technical development most frequently, followed by space development and use of natural resources. Fourth, in the area of STS teaching activities, 'investigation activity' showed highest percentage in 7th curriculum, followed by 'analysis of data', and 'research design', while 'analysis of data' showed highest frequency of appearance, followed by "investigation activity' and 'actual activities' and 'research design' in the order named in 2007 revised curriculum, showing that the area of 'analysis of data' and 'actual activities' increased substantially compared to the 7th curriculum.

• Journal of Environmental Impact Assessment
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• v.14 no.2
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• pp.75-81
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• 2005

The purpose of this study is to understand the appropriateness of land aptitude assessment system and to draw up the improvement of this method. The land aptitude assessment system is used to evaluate the effective demand of land development and land conservation. But, this assessment system has the technical problem of selection standards because the land development and the land conservation are against each other. In terms of the relation between development and conservation of land aptitude assessment system, development was increased rapidly as the economic pressure of local government. The application of the land aptitude assessment system using GIS methods was very useful for local plan. However, this system need to improve the selection standards of GIS parameters and statistical methods for the desirable land assessment system.