• Proceedings of the Korean Reliability Society Conference
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• 2001.06a
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• pp.455-462
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• 2001

We propose a new method to evaluate the network reliability which greatly reduces the intermediate steps toward calculations of maximum capacity flow by excluding unnecessary simple paths contained in the set of failure simple paths. By using signed simple paths and signed flow, we show that our method is more efficient than that of Lee and Park (2001a) in the number of generated composite paths and in the procedure for obtaining minimal success composite paths. Numerical examples are given to illustrate the use and the efficiency of the method.

• Imaging Science in Dentistry
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• v.38 no.3
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• pp.183-187
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• 2008

17-year-old and 14-year-old brothers were referred for evaluation of the cystic lesions on the mandibular anterior area with no symptoms. Neither their mother nor the brothers could recall any past trauma to those areas. Panoramic and intraoral radiographs revealed moderately defined cystic lesions on their mandibular anterior areas. Biopsies on both lesions revealed simple bone cysts. Hereditary cause or familial history of simple bone cysts could not be found in literature review. This case may have been a coincidence. However, further investigation is needed to find the cause of simple bone cysts occurring in patients those are closely related.

• The Transactions of the Korea Information Processing Society
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• v.6 no.10
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• pp.2790-2796
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• 1999

In video-on-demand systems, the I.O bandwidth of video servers is the critical resource which contributes to increase in latency. Several approaches: bridging, piggybacking are used to reduce the I/O demand on the video server through sharing. Batching delays the requests for the different videos for a batching window so that more requests for the same video arriving during the current batching window may be served using the same stream. In this paper, we propose an adaptive reservation-based batching policy which dynamically reserves video server capacity for popoular videos according to video server loads. The performance of the proposed policy is evaluated through a simulation, and is compared with simple batching and static reservation-based batching policies. As the result, we know that the adaptive reservation-based batching policy more improves service ratio and average waiting time than simple batching and simple reservation-based batching policy more improves service ratio and average waiting time than simple batching and simple reservation-based batching polices.

• International journal of advanced smart convergence
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• v.4 no.1
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• pp.127-136
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• 2015

This paper is a study of a simple distillation process. Its objective is to compare fuel production from plastic waste, its data collecting is from the factory and simple data calculated a suitable evaluation on the simple distillation plant built before calculation. The experiment with a simple distillation process is separated into three sections. The first section is a simple distillation process of distillation producing diesel using heat source by biomass. The second section is distillation process which produces fuel using heat source by burner. The third section uses heat source by burner incorporate with biomass. The experiment reveals that the result of the second section is the most efficient. In comparison with the experiments and the simple calculation, the result on the efficiency of work has error less than 5% and it is sufficient for the next experimental process. Thus, the study and design on a simple distillation process produces fuel from plastic waste has to concern mainly on design heat exchangers, flow rate and optimized temperature. Further study on this plant can be developed throughout the county due to its low cost and efficiency.

• Journal of the Korean Professional Engineers Association
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• v.26 no.3
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• pp.65-68
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• 1993

• Journal of the Ergonomics Society of Korea
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• v.26 no.4
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• pp.57-64
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• 2007

In the world, the old population is growing fast and many countries went into an advanced age society. Therefore the development of everyday products, electric appliances, and welfare services considering old people is more important than ever. In particular, the complexity of products can cause many problems for old people. Universal design is an approach to create environments and products that recognizes the diversity of users, regardless of their ability or age. Universality evaluation for a product is very important to verify old people's accessibility and usability for the product. Universality means how good a product was designed in view of universal design principles. In this study, UNIX, a method to evaluate the universality of a product was developed. UNIX was based on seven universal design principles; equitable use, flexibility in use, simple and intuitive, perceptible information, tolerance for error, low physical effort, size and space for approach and use. UNIX is a kind of expert evaluation and very simple method. The method is consisted of two steps. In the first step, relative weights for seven principles and subjective ratings on design suitability for each principle are obtained. In the second step, universality index (UNIX) of each product is obtained by weighted average multiplying relative weights and rating scores. As a case study, this method was applied for mouse designs. In conclusion, this method could be effectively applied to evaluate the universality of a product.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.2
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• pp.85-93
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• 2013

The proportional plus integral(PI) feedback control manner has been used in many general industrial fields such as refrigeration system because of its simple design process and favorable control performance. This paper deals with optimized PI controller design of the refrigeration system based on evaluation functions such as integrated absolute error(IAE). The suggested optimal PI gains can be easily calculated by a simple program and the optimal controllability satisfying the evaluation function can be assured. Furthermore, at the initial step of controller design, the suggested optimal gain is able to reflect some noise disturbances caused by an inverter which drives variable speed compressors. The validity of the suggested optimal gain is investigated by some simulations and experiments to verify its efficiency. From the results of comparing control performance between the optimal PI controller based on the evaluation function and the PI controller designed by the Matlab tuner which was known as the most popular gain tuner, the optimal PI controller showed more desirable control performance especially in transient responses.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.267.1-267.1
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• 2002

The potential allergenicity of the transgene products in genetically modified organisms (GMOs). has been an important issue. As a part of the risk assessment of GMOs. we investigated the physicochemical stability and the immunogenicity of food allergens to determine their allergenicity. We have systematically evaluated the stability of food allergens in the gastrointestinal tract by using simple models of gastric (Stimulated gastric fluid) and intestinal (Stimulated intestinal fluid) digestion. (omitted)

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.10
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• pp.515-529
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• 2017

EnergyPlus, which is widely used in various fields, provides Simple Window Model, a window model that can be used practically. However, the results of building load using the model are different from those of the standard model. The main cause of the deviation by Simple Window Model was analyzed to be due to the assumption that all windows were considered as single layer. The purpose of this study is to propose a window model that improves the cause of deviation by Simple Window Model and can be easily calculated from the algebraic relations. The proposed window model solved the heat balance equation algebraically by using seven window characteristic coefficients. The coefficient relationships consisted of the heat transmission coefficient and solar heat gain coefficient as input parameters make practical use and calculation possible. As a result of comparing the deviation between each window model by implementing the dynamic analysis method, the proposed window model showed that the deviation of the total heating/cooling energy consumption was reduced to 1/3 compared to Simple Window Model for one year. Although the maximum energy consumption did not show any significant improvement, the indoor temperature evaluation showed significantly reduced deviation.

• Journal of the Korean Data and Information Science Society
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• v.14 no.2
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• pp.209-216
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• 2003

Contingent valuation method (CVM) is a main evaluation method of nonmarket goods for which markets either do not exist at all or do exist only incompletely; an example is environmental good. A dichotomous choice approach, the most popular type of CVM in environmental economics, employs binary discrete choice models as statistical estimation models. In this paper, we propose a semiparametric dichotomous choice CVM method using local linear model of Fan and Gijbels (1996) in which probability distribution of error term is specified parametrically but latent structural function is specified nonparametrically. The computation procedures of the proposed method are illustrated with a simple design of simulations.