• Progress in Superconductivity and Cryogenics
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• v.5 no.2
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• pp.51-57
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• 2003

This paper proposes a new oscillating flow model of the pressure drop through the regenerator under pulsating pressure. In this oscillating flow model. pressure drop is expressed by the amplitude and the phase angle with respect to the inlet mass flow rate. In order to generalize the oscillating flow model. non-dimensional parameters, which are Reynolds number, Valensi number, gas domain length ratio, oscillating flow friction factor and phase angle of pressure drop, are derived from the capillary tube model of the regenerator. Correlations for the oscillating flow friction factor and the phase angle are obtained from the experiments for the twill-square screen regenerators under various operating frequencies and inlet mass flow rates. The oscillating friction factor is a function of the Reynolds number alone and the phase angle of pressure drop is a function of the Valensi number and the gas domain length ratio. Experiment is also performed to examine the effect of the weave style of screen. Experimental data demonstrate the superiority of the oscillating flow model over the previous steady flow model.

• Journal of Society of Preventive Korean Medicine
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• v.12 no.3
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• pp.21-34
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• 2008

Objectives : This paper analysed the alternative methods of calculating conversion factor for oriental medicine in the National Health Insurance and estimated the conversion factor(reimbursing price level) of the oriental medical services, based on health insurance claims data and macro economic data. Methods : Comparing cost accounting method, SGR model, and index model to estimate conversion factor in the national health insurance, six empirical models were derived depending on the scope of revenue considered in financial indicators. Classifications of data and sources used in the analysis were identified as officially released by the government. Results and Conclusion : Cost accounting analysis and SGR model showed a two digit decrease in the physician fee schedule of oriental medical services in the national health insurance, while index model indicated a positive increase in the fee reimbursed. As expected, SGR model measured an overall trend of health expenditures rather than an individual financial status of medical institutions, and index model properly estimated the level of payments to oriental medical doctors. Upon a declining share of health expenditures on oriental medicine, a global budget system fixed to a flat rate of total budget could be an opportunity as well as a challenge.

• Journal of the Korean Society of Food Culture
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• v.21 no.4
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• pp.414-419
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• 2006

The purpose of this study was to measure the factor influencing tourist preferences for leaf mustard iimchi. Among 250 questionnaires, 230 questionnaires were utilized for the analysis. Frequencies, conjoint model, max. utility model, BTL model, Logit model, K-means cluster analysis, and one-way ANOVA analysis were used for this study. The findings from this study were as follows. First, the Pearson's R and Kendall's tau statistics showed that the model fitted the data well. Second, it was found that total respondents and three clusters regarded taste and price as the very important factor. Third, it was found that the first cluster most preferred product with light red color, plain package, and mild taste sold at a cheap price in factory. The second cluster most preferred product with light red color, plain package, and moderately pungent taste sold at a expensive price in factory. The third cluster most preferred product with dark red color, shaped package, and highly pungent taste sold at a cheap price in factory. Fourth, it was found that the first cluster most preferred simulation product with light red color, shaped package, and mild taste sold at a cheap price in factory. The second cluster most preferred simulation product with light red color, shaped package, and moderately pungent taste sold at a cheap price in factory. The third clutter most preferred simulation product with dark red color, shaped package, and highly pungent taste sold at a cheap price in factory.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.2
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• pp.39-49
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• 2002

The purpose of this study is to propose an objective and rational methodology for the selection of proposed sites far the National Trust(NT), which is the new alterative proposal far the conservation of natural environments destroyed by injudicious land development and economic growth. That is to enforce many analysis for the effective estimation of rare ecological and landscape resources and to propose a model based on estimation and united indicators. Using the estimative model, we apply it to the selection of the proposed site in micro scale and simultaneously offer the basic methodology of effective and systematic land conservation in macro scale. The results of this study are as follows: 1) The results of analysis for the reliability of estimative items and indicators, presented no problem in that the coefficient of reliability was over 0.7. 2) The correlation measure of the estimative indicator indicated that 'succession'and 'regenerating restorability' were highly correlative in the item of plants. Another three items showed a tendency to be alike. 3) The results of factor analysis on the characteristics of indicators, classified plants into four categories including a stable factor. The item of animals was classified as a stable and rare factor. The item of landscape was classified as a physical and mental factor and the environment as a pollutional and conditional factor. 4) The model of estimation created through factor analysis was valid for the approval of the regression model because significant probability was 0.00. When we consider the NT proposed site as a complex body that is composed of diverse natural and manmade resources, certainly the synthetic methodology of estimation is needed. If these studies are carried out, NT sites will be selected more rationally and effectively than at present. Consequently, they have the potential to play a core role of natural ecosystem conservation in Korea.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1315-1319
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• 2011

As government's policy is enacted to reduce greenhouse gas emission in transportation sector, railroad sector has to estimate amount of emission and propose feasible methods to reduce emission. To calculate accurate emission of railroad sector, we performed a study on the calculation model development for Tier 3 GHG emission factors. According to IPCC guide line, Tier 3 emission factor reflects individual characteristic of diesel locomotive. For this reason, we estimated GHG emission factor by stratified diesel locomotive and the result show difference of emission factor by notch changing. Therefore, the analysis of notch frequency during operation is required to develop Tier 3 emission factor, and we analysed a running pattern of diesel locomotive. As a result, idle and 8 notch consist about 70% of total running distance. In conclusion, the calculation model suppose that Tier 3 GHG emission factor is the sum of multiplied emission factor by weights in each notch. This result can contribute to Tier 3 emission factor calculation and reduction method development of emission in railroad sector by managing driving efficiency and technology development.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1109-1114
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• 2001

This paper describes an attempt to develop a new truss model for reinforced concrete beams failing in shear based on a rational behavioral model. The key idea incorporated with truss model is the internal force state factor which is able to express global state of internal force flow in cracked reinforced concrete beams subjected to shear and bending. A new truss model using internal force state factor may provide a comprehensive result of shear strength in reinforced concrete beams without web reinforcement.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.642-647
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• 1998

A new small-signal model for the controlled on-time boost power factor correction (PFC) circuit is presented. The proposed small-signal model is valid up to high frequencies over lKHz. The model can be used in designing the voltage feedback compensation of PFC circuits, the control bandwidth of which is maximized with auxiliary means of removing the low-frequency ripple from the output. The accuracy of the model is confirmed by a 200W experimental hardware

• The Journal of the Korea Contents Association
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• v.6 no.8
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• pp.20-29
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• 2006

This paper proposes a quality measurement model for video phone service over IP environment. Proposed model enhances conventional E-Model by using quality analysis and this model is suitable for ubiquitous environment. This research measures video phone quality by applying bust packet loss and recency effect. It uses delay and recency effect for compensating actual quality and recognized quality of user using NR and UR factor. Simulation results show that this model can provide more precise results than conventional model by considering recency effect of video phone service quality measurement model.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.6
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• pp.789-799
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• 1999

In this paper, the optimization of fuzzy inference systems is proposed for fuzzy model of nonlinear systems. A fuzzy model needs to be identified and optimized by means of the definite and systematic methods, because a fuzzy model is primarily acquired by expert's experience. The proposed rule-based fuzzy model implements system structure and parameter identification using the HCM(Hard C-mean) clustering method, genetic algorithms and fuzzy inference method. Two types of inference methods of a fuzzy model are the simplified inference and linear inference. in this paper, nonlinear systems are expressed using the identification of structure such as input variables and the division of fuzzy input subspaces, and the identification of parameters of a fuzzy model. To identify premise parameters of fuzzy model, the genetic algorithms is used and the standard least square method with the gaussian elimination method is utilized for the identification of optimum consequence parameters of fuzzy model. Also, the performance index with weighting factor is proposed to achieve a balance between the performance results of fuzzy model produced for the training and testing data set, and it leads to enhance approximation and predictive performance of fuzzy system. Time series data for gas furnace and sewage treatment process are used to evaluate the performance of the proposed model.

• Journal of Ginseng Research
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• v.33 no.3
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• pp.240-243
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• 2009

To better understand how to increase a ginseng grower's revenue, a 4-factor revenue determination model (RDM) of raw ginseng production (R=A Y Q P) was proposed. The total revenue (R) is a multiplicative function of four factors: cultivation area(A), unit yield (Y), quality grade (Q) and unit price (P). The A appears to be a pure capital factor. Y and Q are technological factors and P is social and market factor. When P is constant, the technological term (YQ) is the revenue per unit area (R/A) production efficiency per capital. The RDM appears to be a linear model between R and A with the slope [YQ]. RDM was applied to three farmers' raw ginseng production for assessment of its dependency on capital and technological factors.