• Industrial Engineering and Management Systems
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• v.7 no.2
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• pp.133-142
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• 2008

The Emergency Department (ED) is an integral part of hospitals. Admissions from the ED account for a significant proportion for a hospital's activity. Ensuring a timely and efficient flow of patients through the ED is crucial for optimising patient care. In recent years, ED overcrowding and its impact on patient flow has become a major issue facing the health sector. Simulation is rapidly becoming a tool of choice when examining hospital systems due to its capacity to involve numerous factors and interactions that impact the system. An analytical simulation model is used to investigate potential impacts by changing the following aspects of ED (physical layouts; number of beds; number and rate of patient arrivals; acuity of illness or injury of patients; access to radiology and pathology services; hospital staffing arrangements; and access to inpatient beds). Results of a significant numerical investigation at a hospital are also presented.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.2
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• pp.103-109
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• 2012

This paper analyzed major factors affecting video quality in IPTV (Internet Protocol TV) services in multicasting under our lab network environment similar to practical IPTV service networks. We measured video qualities for the broadcasting traffics in IPTV multicasting with or without applying QoS (Quality of Service) technique. The measurements allowed us to extract thresholds of network measurement factors affecting the quality for the service. It will be a good choice that the factors can be a reference to ensure stable video quality for practical IPTV services in multicasting.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2001.10a
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• pp.163-178
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• 2001

The last few nears have seen significantly increased interest in organic food. Organic food is still a small but growing part of the food industry with an identity defined and protected by law. Its existence provides an element of consumer choice. To obtain consumer confidence and, product credibility and transparency in the organic market, organic legislation and certification is needed, To facilitate export of organic products, harmonization of the organic legislation is favoured. The IFOAM accreditation programme has already achieved very much in this respect. Several national regulation, such as the NOP(USA) and EC2092/91(European Union) have already complied with the IFOAM basic standards. But in many countries there is still a lack of national legislation on organic agriculture. Because of the fast globalisation, organic agriculture is facing major challenges for international trade, so it is very important to consider the future development and certification of organic produce in all countries.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.1
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• pp.133-152
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• 2009

This paper analyze the fee structures of digital music contents and the revenue sharing ratios that are now on-going debates in Korean digital contents industry. Especially we consider Korean situation where copyrighters and telecom companies have conflict of interest. We found two major results. First, the choice between the flat rate scheme and the usage-based rate scheme is not important to telecom companies and copyrighters. The important thing is that copyrighters should decide the revenue sharing ratio and given that telecom companies should decide the retail price. Consequently, this way can lead to win-win solutions between them. Second, the flat rate scheme affects the relationship between consumers and telecom companies. Under the flat rate scheme, telecom companies have more benefits than consumers. In the vertical integrated structure, particularly, this tendency is more severe.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.6
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• pp.333-339
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• 2003

Competition among electric generation companies is a major goal of restructuring in the electricity industry. In electricity market, a huge volume of commodities will be traded through competitive bidding. The choice between uniform and pay-as-bid pricing for electricity auction has been one of most important issues in deregulated electricity market. This paper proposes a constrained Bertrand model for analyzing the electricity auction market of price competition model. The issue of the two pricing rules of uniform and pay-as-bid is studied from the viewpoint of consumer's benefit. This paper also shows that transmission congestion depends on the pricing mechanism. Pay-as-bid pricing gives less possibility of transmission congestion by price competition, and less burden to consumers in the simulation results.

• Child Health Nursing Research
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• v.23 no.1
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• pp.37-47
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• 2017

Purpose: The purpose of this study was to explore the experience of the meaning in life for elementary school students. Methods: The conceptual framework was based on the five main concepts (meaning in life, creativity, experiences, attitudes, choice and responsibility) of logotherapy. Data from 1,600 higher grade elementary school students were analyzed for content of meaning in life. Results: The experiences of meaning in life were identified as follows: Important things in my life (people close to me, things that brings me happiness, to live in earnest, surrounding environment), Activities I like to do (relaxing, achievements, family relationships), Experiences that made me feel like I am loved (taken care of by family, material recompense, being respected), Times when I feel grateful (receive love and care, health), Importance of choices (consequences of bad choices, result of good life choices). Conclusion: These results suggest that elementary school students can understand meaning-centered health education and this kind of education is necessary to promote their wholistic health.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.106.4-106
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• 2001

The current research field to find near-optimum solutions explores in a small population, which is coined as Micro-Genetic Algorithms (${\mu}$GAs), with some genetic operators. Just as in the Simple-Genetic Algorithms (SGAs), the ${\mu}$GAs work with encoding population and are implemented serially. The major difference between SGAs and ${\mu}$GAs is how to make reproductive plan for more better searching strategy due to the population choice. This paper is conducted to implement ${\mu}$GAs in order to achieve fast searching for more better evolution and associated cost evaluation in global solution space. To achieve this implementation, the Air-Borne Selection (ABS) for a new reproductive plan is developed as new strategic conception for ${\mu}$GAs. In this paper, it is shown that the ${\mu}$GAs implementation reaches a near-optimal region much earlier than the SGAs implementation. The superior ...

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.3
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• pp.87-95
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• 2006

In this paper, an approach for analyzing brand loyalty and brand switching behavior in car insurance market is presented. A two-choice model by Blumen, et al. that uses Markov chain is adopted as a main technique for estimating brand parameters. Survey data have been collected through personal interviews with questionnaires. Following the application of the model to the data, it is found that there are five leading companies in car insurance market where the number of potential brand switchers is larger than that of brand loyal customers. Therefore, differentiation of this product along with the conversion of this low-involvement product to a high-involvement one could make car insurance stand out against a somewhat undifferentiated field of competitors.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.519-526
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• 1997

The purpose of this study is to develop the analytical model for the reinforcement bar connection in group-filled steel pipe sleeve, which consists of beam elements for the reinforcement bar and shell elements for the sleeve and the mortar and spring elements for the bond stress-slip relationship. In the reinforcement bar connection using grout-filled steel pipe sleeve, the major variables are the bond stiffness between reinforcement bar and mortar($K_1$) and between sleeve and mortar($K_2$). It is nearly difficult to predict the exact bond stiffness with the experimental results. Therefore, The linearly elastic analyses using ABAQUS, FEM package show the validity of the mathematical equations for the bond stiffness and the choice of material elements in this paper. To predict the behaviour between yield and ultimate tensile strength, the nonlinear analyses must be performed henceforth.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.3
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• pp.231-235
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• 2008

Thyristor rectifiers are still the preferred choice for large magnet power supplies. However, large harmonic voltages, resulting in large current ripple, and slow dynamic response are major drawbacks of these converters. Joos presented a topology and a control technique for a hybrid large-power high-precision magnet power supply in 1996. The system consists of a phase controlled rectifier (PCR) connected in series with a high-frequency PWM converter. This paper improves the power circuit of the PWM converter using interphase transformer. Simulation result proves effect of the proposed system.