• Journal of the Korean Operations Research and Management Science Society
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• v.4 no.1
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• pp.41-51
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• 1979

The Classical multi-server heterogeneous queuing system can be more generalized by using the concept of the switching rules. The descriptions of these systems, the relations among the state probebilities at the various points of interest, and comparisons with the single-server system will be presented. Instead of using the imbedded markov chain we set up the simultaneous equations for the state probabilites by the supplementary variable method.

• Journal of Korean Society for Quality Management
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• v.10 no.1
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• pp.13-15
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• 1982

A device is said to have three states if it has one good state and two mutually exclusive failure modes ; e. g., in one failure mode, it operates when it should not, in the other it doesn't operate when it Should. Some examples of such device include a fluid flow valve, an automatic machine, and an explosive. A Markov model is developed to obtain the availability Function of a 2-unit standby redundant system of such devices.

• Proceedings of the Microbiological Society of Korea Conference
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• 2006.05a
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• pp.44-47
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• 2006

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.882-883
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• 2013

With the development of the society, pure electric vehicles will be surely important of the future. Electric vehicle requires various technology like motor driving, battery management, operational efficiencies and so on. Battery management is indeed the most important to enhance battery's performance and life. This paper has deeply discussed and studied on the lithium-polymer battery management system of pure electric vehicle. First of all we have analyzed the characteristic of the lithium-polymer batteries and the factors influenced on the state of charge. Then a logical SOC measuring method has been raised, which is the combination of open circuit voltage and Ah integration. The next we will introduce the design of battery management system, the battery management system performs many functions, such as inspecting the whole process, when it's running cell equalization protecting and diagnosing the battery, estimating the state of charge. The module design style including microcontroller, data aquisition module, charging control module and serial communication module. To arrive at conclusions, the battery management system which this paper has introduced is reliable and economical.

• Women's Health Nursing
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• v.11 no.4
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• pp.307-315
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• 2005

Purpose: A descriptive study was conducted to identify the change patterns on the level of perceived distress during the early postoperative period with regard to state anxiety in patients using patient controlled analgesia. Method: One hundred women who underwent elective hysterectomy procedures or other gynecologic surgeries completed a series of questionnaires measuring state anxiety, and subjective distress assessed by visual analog scales at 8, 24, & 48 hours postoperatively. Data were analyzed with frequencies, percentages, means, ANOVA, Repeated Measures ANCOVA, and Scheff'e post test utilizing SPSS WIN 11.0. Result: There was a gradual decrease in levels of total distress and pain over the three points in time after surgery regardless the levels of state anxiety. However, women with higher levels of anxiety their pain curve rose at 48 hours post-op. In addition, over the first two points in time, women in the higher anxiety group showed higher levels of distress than those in the lower anxiety group, but no such group differences were observed in the levels of pain, revealing higher pain levels only at 8 hours post-op in both groups. Conclusion: Irrespective of effective pain management modality, most postoperatively experienced distress in gynecological patients was derived from anxiety and pain. These findings have implications for pain management, especially in patients with emotionally charged surgeries like hysterectomy.

• The Journal of Economics, Marketing and Management
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• v.6 no.1
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• pp.1-8
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• 2018

Purpose - Local social commerce market has grown up remarkably. And, Coupang has shown new delivery strategy of rocket delivery. Making new paradigm at local market, Coupang has expanded market scale. This study investigated state of local social commerce market, weight and promotion strategy of Coupang market to find out competitiveness edge of Coupang. Research design, data, and methodology - The study investigated state and concept of social commerce to find out state, problems and competitiveness of social commerce. New distribution service was short of precedent studies. Statistical analysis and experimental analysis were not used, and interview was done to investigate three of social commerce businesses. Results - CRM construction is insufficient to have poor system, Local delivery system could not be made enough at overnight delivery and customers were dissatisfied with ties with another company. Promotion shall be done by delivery system for increase of profitability, funding for more investment, chatbot to build new customer control system, and new delivery system to produce profit. Conclusions - Coupang and others have grown up rapidly to worsen profit and to jeopardize survival. Excessive initial investment has threatened the businesses, for instance, low sales of Amazon, excessive expenses, bench marking of logistics system, and others.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.4C
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• pp.581-593
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• 2004

The interest in wireless LAN security is on the increase owing to a role of high-speed wireless Internet infrastructure of wireless LAN. Wi-Fi has released WPA standard in order to overcome drawbacks of WEP algorithm that is security element of current IEEE 802.11-based wireless LAN system. Pairwise key management and group key management in a mixed-mode which supports both terminals running WPA and terminals running original WEP security are very complicate. In this paper, we analyze flaws in WPA authenticator key management state machine for key distribution and propose the countermeasures to overcome the analyzed problems. Additionally, WPA authenticator key management state machine to which the solutions are applied is described. The reconstructed WPA authenticator key management state machine helps the AP perform efficiently group key exchange and group key update in the mixed-mode.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.437-443
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• 2013

Recently, sustainable building design, a growing field within architectural design, has been emerged in the construction industry as the practice of designing, constructing, and operating facilities in such a manner that their environmental impact, which has become a great concern of construction professionals, can be minimized. A number of different green rating systems have been developed to help assess that a building project is designed and built using strategies intended to minimize or eliminate its impact on the environment. In the United States, the widely accepted national standards for sustainable building design are known as the LEED (Leadership in Energy and Environmental Design) Green Building Rating System. The assessment of sustainability using the LEED green rating system is a challenging and time-consuming work due to its complicated process. In effect, the LEED green rating system awards points for satisfying specified green building criteria into five major categories: sustainable sites, water efficiency, energy and atmosphere, materials and resources, and indoor environmental quality; and sustainability of a project is rated by accumulating scores (100 points maximum) from these five major categories. The sustainability rating process could be accelerated and facilitated by using computer technology such as BIM (Building Information Modeling), an innovative new approach to building design, engineering, and construction management that has been widely used in the construction industry. BIM is defined as a model-based technology linked with a database of project information, which can be accessed, manipulated, and retrieved for construction estimating, scheduling, project management, as well as sustainability rating. This paper will present a framework representing the building knowledge contained in the LEED green building criteria. The proposed building knowledge framework will be implemented into a BIM platform (e.g. Autodesk Revit Architecture) in which sustainability rating of a building design can be automatically performed. The development of the automated sustainability rating system and the results of its implementation will be discussed.

• Journal of Korea Society of Industrial Information Systems
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• v.2 no.2
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• pp.189-207
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• 1997

Recently, we have witnessed a host of emerging tools in the management support systems (MSS) area including the data warehouse/multidimensinal databases (MDDB), data mining, on-line analytical processing (OLAP), intelligent agents, World Wide Web(WWW) technologies, the Internet, and corporate intranets. These tools are reshaping MSS developments in organizations. This article reviews a set of emerging data management technologies in the knowledge discovery in databases(KDD) process and analyzes their implications for decision support. Furthermore, today's MSS are equipped with a plethora of AI techniques (artifical neural networks, and genetic algorithms, etc) fuzzy sets, modeling by example , geographical information system(GIS), logic modeling, and visual interactive modeling (VIM) , All these developments suggest that we are shifting the corporate decision making paradigm form information-driven decision making in the1980s to knowledge-driven decision making in the 1990s.

• IE interfaces
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• v.13 no.3
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• pp.339-347
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• 2000

The use of the Web-based Simulation Environment (WBSE) provides a strong influence on supply chain simulations. A virtual supply chain simulation is available to evaluate strategies for reducing response time to customers and for shrinking the finished goods inventory along its supply chain. This paper presents the basic concepts and definitions of Web-Based Global Supply Chain Management (WBGSCM) simulation system. It also discusses the advantages of supply chain simulation modules integration. A Time Synchronization Mechanism (TSM) called Phased Bucket Scheme (PBS) is introduced as an approach of the distributed simulation modules integration.