• IEMEK Journal of Embedded Systems and Applications
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• v.15 no.6
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• pp.289-297
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• 2020

Although flash disks are being used widely instead of hard disks, it is difficult to optimize for effective utilization of flash disks because overwrite in place is impossible and the power consumption and time required for read, write, and erase operations are all different. One of these optimization issues is a cache management strategy to minimize write operations. The cache operates at two levels: an operating system equipped with flash disks and a translation layer within the flash disk. Most studies deal with the operating system-level cache strategy. In this study, we implement and analyse the DPW-LRU algorithm which is one of the recently proposed operating system cache replacement algorithms to apply to FTL, and grope with some improvements. As a result of the experiment, the DPW-LRU algorithm maintained superiority even in the FTL environment, and showed better performance with a slight improvement.

• Korean Management Science Review
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• v.17 no.1
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• pp.31-40
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• 2000

With the rapidly changing external environment and the increasing internal process complexity more and more organizations are adopting the Electronic Approval System(EAS) for their competitiveness. This paper defines EAS as a core organizational communication medium investigates factors which influence EAS's use from a media rich-ness theory and shows sutiable EAS functions for equivocality resolution and uncertainty reduction. Results from the five EAS implementation sites show that most organizations use EAS only for tasks with low equivocality and low uncertainty. Additional functionalities such as video conferencing and database access were suggested for fu-ture EAS system to enhance their utilization for more cirtical and unstructed tasks.

• Korean Management Science Review
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• v.21 no.2
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• pp.215-234
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• 2004

With enormous changes in market condition, firms try to collaborate with their transaction partners. Recently, the diffusion of the Internet has made it possible for firms to directly collaborate with their partners. Accordingly, the importance of the Collaborative Commerce( C-Commerce) based on the Internet and IT has been emphasized. The literature in relational marketing and strategic alliance, however, has focused on the relational characteristics among firms. Therefore, the fundamental objective of this study is to investigate whether C-Commerce can enhance the positive relationships among firms. Based on theoretical and empirical research, some meaningful discussions can be made. First. the asymmetric commitment between buyers and suppliers decreases the C-Commerce utilization. Second, when specific investment is made to facilitate transactions, firms try to trade efficiently and depend on partners in a long-term period.

• Aerospace Engineering and Technology
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• v.9 no.1
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• pp.84-92
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• 2010

Prior to the launch of COMS Satellite, the validation of the ground system for satellite operations has been performed using the real COMS, the satellite simulator and etc. In particular this paper will focus on the part of ground system test on which the simulator is used and it will present the usage, range and importance of the simulator utilization. Furthermore, it describes the practical experience on and its effect using Simulator for system validation, and suggests approaches to overcome a partial limitation.

• The Korean Journal of Health Service Management
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• v.13 no.2
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• pp.67-79
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• 2019

Objectives: The purpose of this study was to analyze the factors affecting the utilization of emergency medical services and characteristics of emergency medical services according to age group among elderly individuals. Methods: This study conducted t-test and linear regression analysis on data of 1,960,575 participants to achieve the objective. Results: Analysis of the factors affecting the use of emergency medical services showed statistically significant correlation in all age groups. As the age of elderly people increased, the use of emergency medical service increased. Conclusions: Emergency medical policies are needed, such as coordinators with expert knowledge of medical and health administration and specialist emergency room operations that can provide specialized medical service for older patients.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.890-894
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• 2005

Coordination between supply chain partners is viewed critical to effective supply chain management. In many situations such as mutual investments or developing infrastructures for their operations related with each other, the coordination issue arises. Depending on the bargaining power balance between them, it is determined who will be able to exert more influence in making decisions related with such coordination. We consider two cases of the decision-making structure in the context of a simple supply chain consisting of two players, i.e., (1) the first case in which a supply chain partner dominates the decision-making process and the other passively follows the dominant player's decision, and (2) the other case in which the two players share the decision-making process equally. We examine which of the cases is better for the companies and where comes the value of the better case. To answer the research questions, we set up an optimal control theory model and derive an analytical solution. The analysis outcome indicates that the shared decision-making in general produces better results for both companies in the supply chain, and the value of the shared decision-making comes from more effective resource utilization than the dominated case.

• Korean Management Science Review
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• v.12 no.1
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• pp.157-173
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• 1995

Hydro-electric power generation from multi-purpose dams has been playing important roles in the electric power supply network in Korea. Although the total share of hydro power in national electricity supply now becomes very small, the peak-shaving and frequency control capability of hydro power helps the power company enormously in maintaining the quality of power. But since the company that builds and operates the multi-purpose dams in Korea has to sell all the electricity produced to the monopolistic utility, there have been various problems in justifying the investment, designing pricing mechanism, and controlling operations of the power plants. In addition, economic evaluation of the hydro power has been distorted by a variety of reasons and hence it has been very difficult to encourage effective development and utilization of national water resources. To make the problem worse, both parties are public companies with X-inefficiency problems. Thus, changing environment requires to reengineer the system that governs hydro power generation. We address the problems of Korean hydro-electric power generation system in four areas: the investment justification process, the operations decison right of the hydro power plants, the pricing of the purchased-power, and the negotiation of contract revision. Then we propose improvement directions of new hydro-electric power system in view of static and dynamic efficiency, X-inefficiency and equity.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.453-456
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• 2003

Spatial database systems achieve filtering steps with MBR(Minimum founding Rectangle) for efficient query processing, and then carry out refinement steps for candidate objects. While most operations require fast execution of filtering, it is necessary to increase the filtering rates and reduce the number of refinement steps in the low computing powered devices. The compact representation method is also needed in the mobile devices with low storage capacity. The paper proposes various approximation methods for efficient spatial operations in the multiplatform environments. This paper also designs a compression technique for MBR, which occupies almost 80% of index data in the two dimensional case. We also analyze the advantages and drawbacks of each method in terms of space utilization, filtering efficiency and speed.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.582-585
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• 2011

During disaster response, prioritization of limited resources is one of the most important bust challenging tasks. At the same time, it is imperative to timely provide the rescuers with the adequate equipment to facilitate lifesaving operations. However, supply of high demand equipment was insufficient during the initial phase of disaster response, challenging lifesaving operations in the case of the 9-11 terrorist attacks. In respond to the Haiti Earthquake, spatial information of the geographic area was not sufficient to support the search and rescue operations in the early phase of disaster response. However, with the help of civilians, information such as road names, infrastructure damage, and victim locations were updated into the spatial data repository. At the same time, resource outside of the disaster affected zone converges into the area to assist the response efforts, which is the effect of convergence that often made resource coordination challenging in large scale disasters. To efficiently collect information and utilize the converging resources, this paper proposes a flexible data repository for information update for equipment utilization in large scale disaster response scenarios.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.68-77
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• 2010

In this paper, we propose a new log buffer management scheme considering the accessibility of the data. Our proposed scheme evaluates the worth of the merge of log blocks. It conducts the merge operations between infrequently updated data and the data blocks and postpones as much as possible the merge operations between frequently updated data and the data blocks. As a result, the proposed method prevents the unnecessary merge operations, reduces the number of the erase operations, and improves the utilization of the flash memory storage. In order to show the superiority of the proposed scheme, we compare it with BAST and FAST. It is shown through performance evaluation that the proposed method achieves about 25% and 65% performance improvements over BAST and FAST on average in terms of the number of the erase operations.