• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.4
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• pp.15-24
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• 2008

In this paper, we propose a Cross-Layer Transmission Architecture (CLTA) to support power saving high-speed multimedia services in mobile ad-hoc wireless sensor networks(MAWSN). The main goals of this paper are in showing and proposing how the routing routes are decided on route stability based on mobility of mobile nodes to increase the operational lifetime of routes as well as how the transmit power can be saved in mobile ad-hoc wireless sensor networks. To obtain these goals, we propose a cross-layer architecture strategy which combines network layer technology with physical layer technology to get synergy effects in the view of transmission power saving. We consider a realistic approach, in the points of view of the MAWSN, based on mobile sensor nodes as well as fixed sensor nodes in sensor fields while the conventional research for sensor networks focus on mainly fixed sensor nodes. The performance evaluation of the proposed CLTA is performed via simulation and analysis.

• Journal of Navigation and Port Research
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• v.42 no.3
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• pp.207-216
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• 2018

If empty containers from multiple shipping liners are mixed together in the same bay, then the space utilization increases; however, the expected number of re-handles also increases. Formulas for estimating the expected number of re-handles are derived for various storage strategies and two types of handling equipment. The expected number of re-handles is compared, through numerical experiments, among those cases. The results of the numerical experiments are used to analyze the change in the number of expected re-handles according to the change in the retrieval ratio and repair ratio. The impacts of the change in the bay size and the distribution of the storage and retrieval ratio of containers among multiple vessel liners on the expected number of re-handles are analyzed. It is necessary to study efficient operational strategies considering the expected number of re-handles for empty containers.

• The KIPS Transactions:PartA
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• v.10A no.5
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• pp.519-528
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• 2003

Container terminals need decisions in the course of daily-24 hour and 365 day - operations, and all these decisions are inter-related. The ultimate goal of Decision Support System is to minimize ship loading/unloading time, resources used to handle the workload, and congestion on the roads inside the terminal. It is also to make the best possible use of the storage space available. Therefore, the necessity of decision support tools are emphasized to enhance the operational efficiency of container shipping terminals more, because of limits and complexity of these decisions. So, in thia paper, we draw evaluation items for Decision Support Systems and suggest optimization strategy of evaluation items which have the greatest influence on Decision Support system, that is, yard stacking allocation, RTGC deployment among blocks, and YT allocation to QCs. We also estimate the efficiency of Decision Support System design by simulation using G2 language, comparing ship loading/unloading time.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.6
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• pp.25-34
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• 2011

In this paper, In this paper, we propose a Cooperative Routing Protocol (CooRP) for supporting network convergence and transmission services efficiently in mobile ad-hoc wireless sensor networks with Rayleigh fading environments. The main contributions and features of this paper are as follows. First, the routing routes are decided on route stability based on entropy concepts using mobility of nodes within the direction guided line region to increase the operational lifetime of routes as well as reduce control overhead for route construction. Second, a cooperative data transmission strategy based on the constructed stable routing route is used to increase packet delivery ratio with advanced SNR. Third, a theoretical analysis for cooperative data transmission of the proposed CooRP with outage probability is presented. The performance evaluation of the proposed CooRP is performed via simulation using OPNET and analysis. The results of performance evaluation show that the proposed CooRP by using stable routing routes and cooperative transmission can increase packet delivery ratio efficiently.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.371-379
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• 2010

Since Kyoto Protocol to the United Nations Framework Convention on Climate Change in 2005 takes effect, the transportation policies of most countries move toward encouraging the use of the transit mode with energy efficient and low carbon. Korea is 8th country of producing Co2 emissions and will be one of obligation countries decreasing Co2 after year 2013. In order to improve the efficiency of national transport system investment, this study developed the strategies toward rail-oriented transport system by considering operational speed and accessability, rail-oriented development, and introduce of ubiquitous technique in railway. The four major strategies targeted for future year are introduced here such as One-hour rail(connecting major cities within one hour), Seamless 30(accessing major railway stations within 30 minutes, Rail urbanism (railway-based urban planning), and U-rail (railway service with ubiquitous technique). Each strategy includes several action plans and their priorities are investigated using AHP(Analytic Hierarchy Process) to organize them by time scheme as short, mid, and long term perspective.

• Journal of the Society of Disaster Information
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• v.12 no.4
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• pp.321-328
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• 2016

In this study, the characteristics and the status of disaster management in rural area were analyzed. Through this study, we tried to find ways to cooperate with public and private organizations to manage disaster in rural areas. In order to understand the current state of disaster management in rural areas, we surveyed the residents and disaster management officials of local governments. As a result of the survey, both public servants and residents answered that it is difficult for residents to participate in disaster management. This is due to lack of time due to agriculture as the main business. The SWOT analysis and strategy of rural disaster management were derived through the analysis of these surveys. In addition, five types of disaster management network and two types of operation were proposed. Therefore, it is necessary to establish the management plan of the rural disaster management public-private network in the rural area. Further research is needed in depth on each of the operational measures in the future.

• Journal of Korean Library and Information Science Society
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• v.51 no.1
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• pp.43-70
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• 2020

In the context of accelerating the establishment of specialized libraries, this study aims to reestablish the entire system of specialized libraries scattered by Gimpo City as the Gimpo City Library has been in operation for 20 years. It aims to establish a specialized vision and strategy. In this study, the operational problems of the Gimpo library were discussed from three perspectives. First, there is a problem in selecting a special theme. Next is the problem of using specialized materials. Lastly, it is a matter of not operating the actual specialized program. Based on this analysis, three directions for the development of specialized topics were proposed. First, the selection of specialized topics based on local content and user needs. Second, it is necessary to prepare a plan to activate specialized services. Third, local specialty networks should be strengthened.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.5
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• pp.366-372
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• 2013

Korean lunar explorer will be launched by korean launcher KSLV-2 in the 2020s in accordance with national space development strategy. Korean lunar explorer is composed of two unmanned orbiter and lander and should be developed as small size and light weight within 550kg of launch mass due to launcher's loading capability. A structure of lunar explorer is required to have sufficient stiffness and strength under launch and operational environment as well as to accommodate mission equipment. This paper describes the result of a preliminary study on structural model design for korean lunar explorer.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.222-229
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• 2006

The treatment performance and operational parameters of a tertiary wastewater treatment process a biological filtration system were investigated. The biological filtration system consisted of a nitrification filter (Fiter 1) and a polishing filter with anoxic and aerobic parts (Filter 2). SS, T-C-BOD, and T-N in effluent were kept stable at less than 3, 5 mg/L, and 5 mgN/L, respectively, under a HRT in Filter (filter-bed) of 0.37~2.3 h. T-N at the outlet of Filter 2 were about 1~5 mgN/L under the condition of LV of 50~202 m/d. In Filter 2, denitrification was accomplished under LV of 50~168 m/d in a 1 m filter-bed. However, the denitrification capacity reached the maximum when the linear velocity was increased to 202 m/d. Relationship between increase in microorganism and headloss was clearer in Filter 2. As a result, the denitrification rate increased from 1.0~2.3 kgN/($m^3-filter-bed{\cdot}d$) as the headloss increased. The COD removal rate was 6.0~9.6 kgCOD/($m^3-filter-bed{\cdot}d$) when operated with Filters 1 and 2. These results mean that captured bacteria contributed a part of COD consumption and denitrification. The maximum nitrification and denitrification rate was 0.5 and 4 kgN/($m^3-filter-bed{\cdot}d$) in Filter 1 and 2.The ratio of backwashing water to the treated water was about 5~10 %. In Filter 1, wasted sludge in backwashing was only 0.7~5.3 gSS/($m^3$-treated water). In Filter 2, added methanol was converted into sludge and its value was 8.0~24 gSS/($m^3$-treated water). These results proved that this process is both convenient to install as tertiary treatment and cost effective to build and operate.

• Journal of Korea Society of Industrial Information Systems
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• v.18 no.6
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• pp.113-125
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• 2013

Outsourcing is used as one of the effective methods while many companies have to start to innovate everything because of increased fierce global competition, low-growth economy, and varied customers' requirements. Under these conditions, a lot of firms are introducing outsourcing for cost savings, risk reduction, management efficiency, strengthen core competence. The purpose of this study is to analyze the effect of between outsourcing success by outsourcing strategy and factors for selecting outsourcing partners and BSC success in the Korea manufacturing. This study was intended to make it possible to get a practical approach on evaluation and compensation of the outsourcing manufacturing enterprises by identifying outsourcing success factors and BSC performance factors. When an outsourcing partner of enterprise is selected, detailed assessment will be possible in terms of partner's competence, financial factors, institutional factors, and operational factors.