• Journal of applied mathematics & informatics
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• v.15 no.1_2
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• pp.53-75
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• 2004

First, we present two classes of sequential algorithms for minimum flow problem: decreasing path algorithms and preflow algorithms. Then we describe another approach of the minimum flow problem, that consists of applying any maximum flow algorithm in a modified network. In section 5 we present several parallel preflow algorithms that solve the minimum flow problem. Finally, we present an application of the minimum flow problem.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.401-402
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• 2006

In the present paper, approximate plastic limit load solutions for pipe bends under combined internal pressure and bending are obtained from detailed three-dimensional (3-D) FE limit analyses based on elastic-perfectly plastic materials with the small geometry change option. The present FE results show that existing limit load solutions for pipe bends are lower bounds but can be very different from the present FE results in some cases, particularly for bending. Accordingly closed-form approximations are proposed for pipe bends under combined pressure and in-plane bending based on the present FE results. The proposed limit load solutions would be a basis of defective pipe bends and be useful to estimate non-linear fracture mechanics parameters based on the reference stress approach.

• Journal of the Korean Institute of Rural Architecture
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• v.9 no.3
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• pp.73-82
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• 2007

Ministry of Education and Human Resources presented on December, 2006, 'Alternative school establishment and operation regulation' of contents that can be recognized attainments in scholarship because is authorized if alternative schools fulfill fixed condition. Even though, one time, it was true that several opinions which try to limit to adaptation school of person disqualified for school, thus, various discussion and efforts that specialized school for alternative education does to grow are appearing. However, the expectation which a lot of non authorized schools will apply is not so high because specialized school for alternative education will be controlled in free curriculum and school operation that have been administered and can not be guaranteed school's sell-regulation if acquire legal authorization. Under such social and educational background I surveyed present condition, law, system, literature investigation of existing study, Japanese system and example and authorized two sample specification schools etc. through 'A Basic Study on the Optimum Facilities Criteria Modeling of Regional Specialized Schools for Alternative Education(2006. 10)'. This study was preceded the succession and I visited 17 schools that permit investigation opening of schools among 29 that is authorized until present. So I try to find out architectural planning criteria to activate specialized school for alternative education more through analyzing school's general present condition, establishment idea, operation and specialized education plan, facilities present condition and characteristic.

• International Commerce and Information Review
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• v.5 no.1
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• pp.181-202
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• 2003

This study investigates the present status and development of e-marketplace which is the most actively used in the e-trade stages from market research, searching for business partners, negotiations to contract. It also shows the present status and development of e-marketplace as an "e-trading company" designated by government, which gives prospect of profitable model of e-marketplace. Especially focused on EC21 - the best e-marketplace of Korea, this study views present status and development of EC21 and trading companies applied for EC21, government designated e-trading company, to receive electronic trading support services. In addition, we hope that the findings of this study will be a helpful material to government for making policy and framing supporting project toward leading organizations of e-trade such as Ministry of Commerce, Industry and Energy, e-trade promotion committee of Korea International Trade Association and small-ta-medium companies interested in e-trade, to activate e-trade.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.241-244
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• 2006

The present paper describes the scale effect correction method for wind turbine by using CFD(computational fluid dynamics). For the correct ions of wind turbine scale effect, various researches on the helicopter rotor scale effect were Investigated and feasibility study of methods was performed to correct wind turbine scale effect The present paper also introduces new scale effect correction method based on two dimensional lift slope modification. In order to test the Present method, performance analyses of NREL Phase VI wind turbines under various scale conditions were carried out by using CFD. The present method showed reasonable results when applied to NREL Phase VI wind turbine.

• Journal of Korean Neurosurgical Society
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• v.38 no.3
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• pp.165-183
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• 2005

Surgery for temporal lobe epilepsy refractory to medical treatment is a promising treatment option. After a short overview on historical developments in this field, we describe the present practice of presurgical evaluation and resection strategies as practiced at our institution and review the corresponding publications from other centers. We try to delineate major future developments for surgical therapy of temporal lobe epilepsy, as they can derived from present trends.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.4
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• pp.158-170
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• 1998

In this study, we divide greenspace in Suwon city into three parts, that is, the conservation part, the maintenance part and the creation part by considering the quantitative aspect of greenspace and the present targets. To do it, two steps are taken. Firstly, assuming that the target year is 2007, the final target of greenspace area is established by combining targets presented in present state survey, the evaluation of resident perception and the future population estimates. The target of greenspace area in present state survey is 7,887,062$m^2$+$\alpha$ and that of greenspace area demanded in the evaluation of resident perception is 8,242,419$m^2$. Demand of greenspace area based on population estimates is 4,227,513$m^2$. When the greenspace needed in the city is added, the target may be more than 8,242,419$m^2$ which is demanded in the evaluation of resident perception. Outcome of the present state survey, 7,887,062$m^2$ + $\alpha$, is considered to be enough to accomodate the greenspace area demanded in the evaluation of resident perception and the population estimates. Therefore, targets of greenspace in Suwon City was established based on the area of greenspace analyzed in the present state survey. Secondly, the target of greenspace is divided into three parts, that is, the conservation part, the maintenance part and creation part. And the methods to attain the target are presented. In order to set desirable targets of urban greenspace, it is necessary to combine the outcome of present state survey, the resident perception, the population estimates and the various urban conditions. If the results of this study are applied to the urban planning or other related planning, the urban ecosystem will be protected and the biotope will be created.

• Journal of The Korean Association For Science Education
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• v.17 no.4
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• pp.525-540
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• 1997

The present study tested the hypothesis that maturation of the prefrontal lobes is a crucial factor determining the performance of scientific reasoning tasks, Functions of the prefrontal lobes, such as activating relevant information, sequential planning and monitoring, and inhibiting irrelevant information, are related thinking patterns with scientific reasoning. Therefore, we inferred the idea that the prefrontal lobes play an important role in scientific reasoning. To test the hypothesis. the present study investigated a prefrontal lobe patient's task solving procedures in scientific reasoning tasks and the correlation and regression analysis between a test of prefrontal lobe function and two scientific reasoning tasks, The perseverative errors in the Wisconsin Card Sorting Test(WCST) was used as a measure of the prefrontal lobe function, The Melinark Type Task and the Classroom Test of Scientific Reasoning were used as measures of scientific reasoning abilities. Ages and Group Embedded Figure Test were also used as measures of two alternative hypotheses, general maturation and field independency respectively. The prefrontal lobe patient showed a crucial deficiency in solving scientific reasoning tasks. In the tasks, the patient could not used the reasoning of If... and... then... therefore pattern. In correlation study, the perseveration errors of the WCST showed a significantly negative correlation with two scientific reasoning tasks. Multiple regression study also showed that the perseveration errors measured as a function of the prefrontal lobes have more contribution to scientific reasoning ability than contributions of alternative hypotheses. Therefore, the present study supported the hypothesis that prefrontal lobes play a crucial role in scientific reasoning ability, What function of the prefrontal lobes do play crucial role in scientific reasoning? The present study provided an explanation for the question, which inhibiting ability of the prefrontal lobes is responsible for the scientific reasoning ability, in a part at least. That is, perseverative tendency in task-solving procedures causes a deficiency of an ability to inhibit the wrong information to solve a task. The present study provided a possibility of neuropsychological approach in science education research. The present study also showed an importance of the prefrontal lobe development in the performance of scientific reasoning task.

• Journal of Distribution Science
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• v.14 no.12
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• pp.99-105
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• 2016

Purpose - In the present study, it has become the most important necessity in our daily lives that consumers' psychological factors affect the use of smartphones, and it has been analyzed through behavioral economic approaches. In this respect, the present study is intended to apply the heuristic theory and the prospect theory among behavioral economics theories to examine how psychological factors affect consumers' product selection. Research design, data, and methodology - In the present study, using smartphone repurchase as a dependent variable, whether regulatory focus effects have interaction effects on behavioral economic theories and behavioral economic effects such as possession (ownership) effects, framing effects, and brand recollection. As an analysis method, questionnaire surveys conducted with university students in Incheon were examined through Two-Way ANOVAs using the SPSS23 package. Results - The analysis from the results are as follows. Using smartphone repurchase as a dependent variable, the main effects and interaction effects on two variables; satisfaction difference with product functions and positive framing variable were statistically significant. Using repurchase as a dependent variable was statistically significant, there was no interaction effect between the two variables; satisfaction difference with product functions and the difference of brands in possession. Using smartphone repurchase as a dependent variable, interaction effects on two variables; satisfaction difference with product functions and the lengths of product possession periods were not statistically significant. The results from the analyses of interaction effects of brand recollection and brands type were statistically significant in possession using repurchase as a dependent variable. The results from the analyses of the main effect of the brands type were statistically significant in possession using repurchase as a dependent variable. Conclusions - The implication of the present study is that it suggests the factors that became important for customers' smartphone purchase following the change in the meaning of smartphones from practical products in the past to hedonic products. Limitations of the present study are first, the study subjects are limited to students and the number of copies in questionnaires is only approximately 130, which is insufficient, so that the present study is not sufficient as a study for entire smartphone users.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.4
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• pp.684-695
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• 1992

The present study is concerned with the analysis of three-dimensional sheet metal forming process by the upper-bound method. For the analysis a systematic approach is necessary for the expression of geometric configuration of the deforming workpiece. In the present paper geometric configuration is constructed by three unit surfaces which are defined by sweeping the vertical section curves and boundary curve. The principal components of strain increment during the process is calculated directly from the change of geometric configuration for an arbitrary triangular element. The corresponding solution is found through optimization of the total energy consumption with respect to some parameters assumed in the velocity field and geometric profile. In order to verify the effectiveness of the present method, hydrostatic bulging of a rectangular disphragm is analyzed and the computation by the present method for the geometric shape renders the good result. From the comparison of the present results with the existing experimental results and elastic-plastic finite element solutions, good agreements have been obtained for the pressure curves, polar membrane strains and pressure distributions. The present method can thus be further applied to the analysis of other three-dimensional sheet metal forming processes.