• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.8
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• pp.1532-1541
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• 2015

D2D(Device-to-Device) communication is a promising technology to improve the system capacity and spectral efficiency. By sharing the same radio resources with cellular user equipments, D2D communications can significantly enhance the overall spectral efficiency. However, it may cause interference between D2D link and cellular link. So, careful resource allocation and interference coordination between them are very important and need to be properly handled. This paper proposes a radio resource allocation scheme that decreases interference through the use of area grouping and D2D pair grouping. Simulations results are provided to verify the performance improvement of the proposed scheme in terms of the number of assigned resource blocks and computational complexity.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.2
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• pp.95-100
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• 2005

In order to improve the gill nets for croaker, Miichthys miiuy which is proper to the fishermen's income ans fisheries resource management, we had studied to the net height of present gill nets (mesh size 160mm, 50 mesh in depth), experimental gill nets-I(mesh size 150mm, 68 mesh in depth) and experimental gill nets-II(mesh size 142mm, 75 mesh in depth) in wter using the gill nets design ans analysis simulation system, and then investigated and analyzed the catch efficiency of each gill nets through the field fishing experiments. The net height of emperimental gill nets-I and experimental gill nets-II in water were estimated respectively about 1.5 times and 1.3 times higher than present gill nets which the net height is about 3.5m as the results of simulation considering the current of fishing fields. Total number of croakers which were caught by the persent gill nets was 62(body length 300~1,200mm), total catch weight was 398.7kg (mean 0.6kg/sheet). Total number of croakers which were caught by the experimental gill nets- I was 68(body length 600~1,100mm), total catch weight was 391.6kg (mean 1.2kg/sheet). Total number of croakers which were caught by the experimental gill nets-II was 28(body length 400~900mm), total catch weight was 99.2kg (mean 0.3kg/sheet).

• Korea Journal of Hospital Management
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• v.13 no.3
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• pp.69-93
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• 2008

Rising healthcare cost is a global phenomenon that justifies governments' introduction of 'incentive regulation' plan for the improvement of hospital efficiency. A number of previous studies tried to evaluate the efficiency of healthcare organization by using Data Envelopment Analysis(DEA), a common efficiency benchmarking method. However, there is a concern that this kind of efficiency evaluation could induce "quantity-quality trade-off". Moreover, as quality aspect is especially important in terms of 'effectiveness' of health care, it should be considered in efficiency evaluation of healthcare organization. A number of different models were tried so far to incorporate quality aspect into DEA, however, none is universally recognized as a standard. Thus, in this study, previous quality-incorporating DEA models were categorized into 6 types according to the way of incorporating quality aspect, and strengths and limitations of each type were reviewed with a set of artificial data as an example. Based on this review, a new quality-incorporating efficiency evaluation model, named Quality-adjusted output DEA(QAO-DEA), was suggested. As an exploratory empirical analysis, technical efficiency of human resource were measured with different quality-incorporating DEA models, using 2004 data from National University Hospitals. In conclusion, Quality-adjusted output DEA(QAO-DEA) model seems to be one of the most desirable alternatives to incorporate quality aspect in efficiency evaluation of hospital, and deserves the consideration as a policy tool to induce simultaneous improvement of both efficiency and quality.

• Journal of Digital Convergence
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• v.19 no.10
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• pp.229-240
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• 2021

As the environment and rivalry of Regional Agricultural Cooperatives(RACs) becomes more unfavorable, the pressures to enhance organizational performance are strenghthened. Existing studies suggest efficiency improvement through resource sharing(RS) to fix the issue. In this context, I intend to find if RS still increases organizational performance in another form of organization on the basis of 132 business units(BUs) of 45 RACS. According to empirical results, resource similarity between BUs and resource level of BU increases RS respectively, and RS increases BU's performance. The RS also has mediating effects on similarity and resource level into performance. But the overall resource level of RAC has no influence on RS and there is no mediating effect. My contribution is to confirm the efficacy of RS in half-profit organization and to verify determinants and performance implications of RS.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.1
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• pp.283-290
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• 2016

As the development of recent science and technology, high-performance computing resources is needed to solve complex problems. To reach these requirements, it has been actively studied about grid computing that consist of a huge system which bind a heterogeneous high performance computing resources into on which are geographically dispersed. However, The current research situation which are the process to obtain the best results in the limited resources and the scheduling policy to accurately predict the total execution time of the real-time task are very poor. In this paper, in order to overcome these problems, we suggested a grid computing-based risk management system which derived from the system structure and the process for improving the efficiency of the system, grid computing-based working methodology, risk policy module which can manage efficiently the problem of the work of resources(Agent), scheduling technique and allocation method which can re-allocate the resource allocation and the resources in problem, and monitoring which can manage resources(Agent).

• Journal of the Korean Society of Industry Convergence
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• v.25 no.1
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• pp.71-78
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• 2022

With the advent of cutting-edge technology, renewable energy is significantly considered as alternative resources to supply electric power. However, many barriers such as energy intermittency, high initial installation cost, and low-efficiency generation challenged building new infrastructure with clean energy. Efforts reducing greenhouse gas emissions and reliance on fossil fuels resulted in the decentralization of power generation like distributed energy resource (DER). This paper is to introduce and evaluate the feasibility of building-integrated photovoltaics (BIPV) in a high-rise building in Ulsan. To optimize BIPV, a variety of methods to minimize efficiency decrease and maximize electric power generation after installing BIPV on the building's facade are suggested. The variables causing power losses are analyzed. By utilizing System Advisor Model (SAM), actual power generated from solar panels is measured by Thin-film PV, Mono-crystalline PV, and Poly-crystalline PV.

• International Journal of Highway Engineering
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• v.20 no.2
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• pp.109-118
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• 2018

PURPOSES : This study evaluates the efficiency of snow removal operation resources using data envelopment analysis (DEA). The results of this study can help decision-making strategies, especially for resource allocation for snow removal works on national highways. METHODS : First, regional road management offices (DMUs) for efficiency evaluation were set up, and a database (for years 2012-2016) for analysis was formed. Second, DEA was carried out by selecting input and output variables based on the constructed database. Lastly, based on the results of the DEA, the efficiency of each regional road management office was evaluated. In addition, the potential for future improvement was determined. RESULTS : The results showed that there was a large variation in efficiency of snow removal operation resources by regional offices. CONCLUSIONS : The results of this study imply that the evaluation of efficiency for snow removal operation resources is important when decisions related to snow-removal strategies are made by road management offices.

• International journal of advanced smart convergence
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• v.9 no.3
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• pp.17-27
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• 2020

With the continuous development and application of Internet technology, in recent years, new technologies such as cloud computing, big data, the Internet of Things, and AI are becoming more and more familiar to the general public. The development of a digital society has entered a new period of development. In this paper, we used on the 2018 annual data of 50 listed companies with blockchain concept stocks in China. Using data envelopment analysis (DEA) to study and analyze the input-output efficiency, it can be concluded that the input-output efficiency of 50 listed companies is very different. Inefficient companies are as high as 62%. Most companies have a large room for improvement in input-output efficiency due to uneconomical scale or inefficient technology. In order to better improve the company's input-output efficiency, one must improve the efficiency of resource utilization, optimize the company's research and development costs and the input and management of technical personnel; the second is to increase technological innovation and business innovation.

• Journal of the Korean Operations Research and Management Science Society
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• v.28 no.4
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• pp.155-189
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• 2003

In this research, the comprehensive evaluation model of IS(information systems) for public sectors is theoretically constructed through reviewing and integrating previous IS evaluation-related research. This model is hypothesized to consist of five sectors(System Sector, User Sector, Organization and Management Sector, Resource Management Sector and Strategic Contribution Sector), ten evaluation items belonging to these five evaluation sectors, and sixty two evaluation indices for these ten evaluation items. The results of empirical analyses to test the validity of the research model show that the evaluation sectors turn out to be the same ones as proposed in the hypothetical model. The evaluation items(System Quality, Information Quality, Service Quality) in System Sector proves to be consistent with the hypothetical model. However, in case of User Sector, two evaluation items(Perceived Usefulness and User Satisfaction) which are included in the hypothetical model are found to be merged into one item(User Satisfaction). And, it is shown that four evaluation items such as the Efficiency of Internal Process, Customer Satisfaction, Organizational Innovation, and the Degree of Informatization competence improvement are included in Organization and Management Sector, differently from the research model in which the items, Organizational innovation and the Degree of Informatization competence improvement, are not divided. As a final result, sixty two evaluation indices that comprise all the evaluation items belonging to five sectors are found to be reduced to fifty seven ones through factor analyses, criterion-related validity tests and reliability analyses.

• Korean Journal of Computational Design and Engineering
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• v.10 no.3
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• pp.210-216
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• 2005

Digital manufacturing could be very effective in shipbuilding in order to estimate the process time, to improve the operation efficiency, and to prevent bottleneck processes in advance. The subassembly process having done research consists of piece arrangement, tack welding, robot welding, manual welding and so on. The robot welding of them was the focus of the simulation. The analysis and modeling were carried out by using UML (Unified Modeling Language) as well as $IDEF\phi$ (Integration DEFinition). The characteristics of the process resources were analyzed using the shipyard data, and the layout of the subassembly line was designed with the resources. Using the constructed resource and process model, the productivity and efficiency of changed robot welding stage were investigated. It was simulated how much the variations in the resource performance have influence on improvement of productivity. One of the important outputs in this simulation was the cycle time during a certain period's work. The cycle time prediction was also undertaken for the different torch and the different piece arrangement. The proposed model was established three-dimensionally in a digital environment so that interferences among objects and space allocations for the resources could be easily investigated.