• 수산경영론집
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• 제43권2호
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• pp.51-66
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• 2012

The purpose of this study is to present a new business performance model suitable for marin repair business. For this propose we have used survey datas gathered on several input and output factors from Marine engin repair companies Yeong-Do Gu. Gathering these the survey results we estimated the efficiency of each company through DEA method. The results of the analysis can be summarized as follows ; First, the result of the analysis showed 7 out of 24 DMU are not efficient companies. On the other hand 17 of them are efficient as the efficient output analyzes showed. Second, by analysing the results we could see significant differences between group companies, Ltd with a private companies with share on average efficiency in utilization. Third, two of the private companies are more effective and 6others were selected revisit and interview on the analysis. As a result inefficient DMU compared to efficient DMU and showed that they invest more on manpower in the field of sales and professional managers and techicians. Also, lots of effort devoted in order to standardize production by building capacity and environment management to improve welfare of the workers.

• 한국환경보건학회지
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• 제29권2호
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• pp.45-49
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• 2003

In this study, lots of methods have been studing to utilize energy and decrease contaminated effluents. There has been great progress on IGCC (Integrated gasification combined cycle) to reduce thermal energy losses. The following results have been conducted from desulfurization experiments using waste shell to remove H$_2$S. According to TGA results, temperature had influenced on H$_2$S removal efficiency. As desulfurization temperature increased, desulfurization efficiency increased. Also, maximum desulfurization efficiency was observed at 80$0^{\circ}C$. Desulfurization was related to calcination temperature. Considering temperature ranges of exhausted gas from hot gas gasification equipment were 400~80$0^{\circ}C$. Thus, desulfurization efficiency would be increased desulfurization temperature situation at highly. Experiments by TGA showed that particle size of sorbents had influenced on desulfurization capacity. Maximum desulfurization capacity was observed at 0.631 mm for oyster and clam. Rest of sorbents showed similar capacity within 0.171~0.335 mm particle size range. So, particle size would be considered. When would be used waste shells as IGCC sorbents. According to the results about desulfurization capacity by TGA, oyster had the best desulfurization capacity among limestone and waste shell. We would be identify to substituted oyster for existing sorbents

• 산업경영시스템학회지
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• 제32권1호
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• pp.44-51
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• 2009

A bonded warehouse is the warehouse located in bonded area. It functions not only as a general warehouse but also as a place for managing the work related to import and export bonded goods. As a general warehouse, it uses the rack system to store the goods and the folk lift truck to move the unitized goods. The operation of the storing system closely related to the efficiency of space uses in a warehouse and vehicle working. Thus, vehicle performance measured in distance units in the ware-house could be used as one of the key performance measure in warehouse system. This paper focuses on the operation efficiency of the bonded warehouse which uses rack system for the storing and the folk lift truck for moving goods. The method of load allocation for balancing the rack uses and vehicle operation for maximizing efficiency are the specific concerns in this paper. The simulation study is conducted to find a policy for efficient vehicle operation based on balanced rack utilization, and the favorable result for the system operation would lead the usable proposal in vehicle operation.

• Asian-Australasian Journal of Animal Sciences
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• 제1권1호
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• pp.7-12
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• 1988

Twenty cows, by order of calving, were used in a completely randomized $2{\times}2$ factorial experiment. Variables were tow protein levels (14 and 18% crude protein) and concentration of fat (2 and 6% ether extract) in diets. Fat addition, via unprocessed whole sunflower seed, insured forage utilization in diets to meet energy requirement of cows. A total of 36 wks of lactation was subdivided into three 12-wk stages of lactation. Net energy lactation was set at 1.72, 1.57 and 1.42 Mcal/kg for each stage. Higher protein diets improved the efficiency of energy (FCM/net energy intake) which was particularly noted for diets containing high fat (85.7%). However, diets with low protein-high fat resulted in the lowest efficiency (67.7%). No difference in milk yield and butterfat was due to different levels and combinations of protein and lipid in diets. High protein diets depressed blood cholesterol and glucose compared to low-protein counterparts. Relative decline in milk production was slower for lower fat diets than for higher fat groups, especially mid to later stage of lactation. Results of this experiment tend to support our thesis on the synergistic effect of dietary protein and energy (lipid) upon efficiency of lactation.

• Journal of Power Electronics
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• 제16권5호
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• pp.1629-1638
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• 2016

Differential power processing (DPP) systems are among the most effective architectures for photovoltaic (PV) power systems because they are highly efficient as a result of their distributed local maximum power point tracking ability, which allows the fractional processing of the total generated power. However, DPP systems require a high-efficiency, high step-up/down bidirectional converter with broad operating ranges and galvanic isolation. This study proposes a single, magnetic, high-efficiency, high step-up/down bidirectional DC-DC converter. The proposed converter is composed of a bidirectional flyback and a bidirectional isolated switched-capacitor cell, which are competitively cheap. The output terminals of the flyback converter and switched-capacitor cell are connected in series to obtain the voltage step-up. In the reverse power flow, the converter reciprocally operates with high efficiency across a broad operating range because it uses hard switching instead of soft switching. The proposed topology achieves a genuine on-off interleaved energy transfer at the transformer core and windings, thus providing an excellent utilization ratio. The dynamic characteristics of the converter are analyzed for the controller design. Finally, a 240 W hardware prototype is constructed to demonstrate the operation of the bidirectional converter under a current feedback control loop. To improve the efficiency of a PV system, the maximum power point tracking method is applied to the proposed converter.

• 환경생물
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• 제25권3호
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• pp.228-238
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• 2007

Calcium plays an important role for the organisms' physiology, reproduction, and growth. Calcium amount and transfer efficiency along trophic levels were compared at two different geological areas, Limestone area (LS) and Granitic Gneiss area (GG) in 1992 and 1993. Biomass and calcium amount of plants, herbivores and carnivores were seasonally measured. The removal sweeping net method was used to collect the quantitative insect samples. Calcium content (mgCa $g^{-1}$ DM) and pH of soil were 4.85 and 7.3 at LS and 0.21 and 7.3 at GG. The calcium transfer efficiencies (%) at LS and CG were 0.2 and 4.2 from soil to plants, 0.002 and 0.02 from plants to herbivores, and 73 and 47 from herbivores to carnivores, respectively. As a whole, the high calcium content of the LS soil reduced the utilization of calcium by plants. The higher trophical levels were, the higher ecological efficiency of the biological levels was. The calcium transfer amount was higher at LS, but its efficiency was rather higher at GG.

• 수산해양교육연구
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• 제20권3호
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• pp.500-507
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• 2008

Hot air drying is a method that let moistures evaporate by heat exchange between heating air and dry target. This way is dominating more than about 70% of dryers that the use extent is wide fairly, and is established in domestic than dryer that use conduction or radiation etc. Most of research about drying had been emphasized in size of device through analysis for these dry phenomenon plain, heating topology, and aspect of form and so on by dry target's special quality, and research about device development or waste heat withdrawal technology in energy utilization efficiency side is slight real condition. Therefore, in this study, Investigated numerically about thermal efficiency elevation that is leaned against as that change the temperature of inlet and outlet in heat exchanger of the hot air drying tower.

• 산업공학
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• 제16권spc호
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• pp.76-81
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• 2003

BPMS (Business Process Management Systems) is aninformation system that systematically supports designing, administrating, and improving the business processes. It can execute the business processes by assigning tasks to human or computer agents according to the predefined definitions of the processes. In this research we developed a task assignment algorithm that can maximize overall process efficiency under the limitation of agents' capacity. Since BPMS manipulates the formal and predictable business processes, we can analyze the processes using queuing theory to achieve overall process efficiency. We first transform the business processes into queuing network model in which the agents are considered as servers. After that, workloads of agents are calculated as server utilization and we can determine the task assignment policy by balancing the workloads. This will make the workloads of all agents be minimized, and the overall process efficiency is achieved in this way. Another application of the results can be capacity planning of agents in advance and business process optimization in reengineering context. We performed the simulation analysis to validate the results and also show the effectiveness of the algorithm by comparing with well known dispatching policies.

• 조명전기설비학회논문지
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• 제15권2호
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• pp.1-6
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• 2001

우리 나라의 터널 조명은 운전자의 시야상태를 저해하는 불균일한 조도 균제도, 터널 내의 플리커 현상, 심한 눈부심 등과 함께 낮은 기구효율, 낮은 조명률, 높은 에너지 소비 등의 문제점을 갖고 있다. 이러한 것들을 개선 하기 위해서 터널용 고효율 조명기구의 반사판을 개발하였고, 개발된 조명기구는 기구 자체 효율이 10%이상 상승함으로써 에너지의 절감과 조명효과의 상승을 가져왔으며, 기구 대수의 저감으로 시설비를 절감할 수 있다. 또한 이것을 이용한 터널조명에서는 평균조도 200[lx]이상, 전반 균제도 0.4이상, 차선축 균제도 0.7이상, 단위 면적당 소비전력 3.7 [W/m$^2$]이하의 효과를 얻었다.

• 한국군사과학기술학회지
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• 제22권1호
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• pp.106-123
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• 2019

Demand for performance analysis is increasing for efficient use of limited budgets such as improving investment efficiency and strategic budget allocation in accordance with the continuous increase demand of R&D budget for developing advanced weapon systems in the future battlefields. In accordance with the Act on the Performance Evaluation and Performance Management of the National R&D Projects established in March 2006, the performance analysis has been conducted for the systematic management and utilization of the R&D project performance. It was recognized as a project to achieve self-defense through strengthening the weapons system development capability, however, efficiency evaluation of Defense R&D projects was not much emphasized. Research on the efficiency analysis of defense R&D projects has been conducted in recent years, but most studies focused on corporate efficiency and productivity of defense companies. In this study, we analyzed the three-stage performance of defence R&D projects based on the logical model using the data envelope analysis(DEA) model. We also analyzed performance analysis from various perspectives through R&D type, technology classification and performance model. This study is expected to help defense department improve defense R&D projects and make decision.