• Journal of Drive and Control
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• v.15 no.2
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• pp.38-45
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• 2018

In this study, the theory of fluid mechanics and dynamics is used to build a mathematical model for a three-stage flow control valve. The significance of the study is that the mathematical model can easily be used to study the effect of different design parameters on the performance of the valve. The geometry of the valve and the properties of the fluid were used in this study to determine the variation in the performance of the valve when varying the magnetic force on the pilot spool. While a linearization technique is not used to solve the developed model, the solution of the mathematical model is found in the time domain by simulation of the equations using a software package. The results indicate that if the developed mathematical model is solved for the different values of magnetic force, the valve behaves linearly; the valve is thus called the proportional flow control valve.

• Journal of the Korean housing association
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• v.23 no.4
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• pp.33-40
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• 2012

Managing apartments is critical not only to handling the physical deterioration over time, but also to the quality of community life, social environment and ultimately residents' satisfaction with the housing environment. Therefore, this study aims at understanding residents' awareness of apartment management, and finding the relationship between management activities and residents' satisfaction and participation by comparing an apartment with active management and an apartment without it. This study examines 1) management activities of two subject apartment complexes, and 2) how management activities affect residents' participation and satisfaction. Surveys were conducted of the residents, and SPSS statistics package was utilized to analyze the survey data. This study found that management activities of apartment complex have positive influence on residents' participation and satisfaction with their housing environment. The results of this study can be utilized as basic materials to develop effective guidelines and manual from the perspective of environmental management of apartment houses, in order to improve the participation of the residents in the apartment management.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.14 no.1
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• pp.5-24
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• 2003

In recent years, electronic technologies are rapidly changing the library's approach to collection management. In digital age, collection is a hybrid, that is, a mix of analog materials and digital information resources. But electronic publications are both a blessing and a curse for libraries. And the rapid acceptance of electronic resources raises many misconceptions and myths about their capabilities. This paper analyzes the digital paradox of current collection management from six standpoints : production of digital informations : digital scholarly communication : digital access paradigm : acceptance of e-journal package web collection development : digital archiving. Nowadays the pragmatic view of library is a logical information gateway to its own services and those of other libraries and information providers. Libraries and librarians need a concept and strategies of the hybrid collection management that reflects digital reality.

• Journal of the Korean Home Economics Association
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• v.29 no.4
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• pp.65-80
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• 1991

The present study was designed to find out demanding characteristics about a desk in the teenager's housing lifestyles. Documentry research and questionnaire survey methods were used in this study. Questionnaire were administered to 233 teenagers in seoul. Data were analyzed with the use SPSS PC+ package. The statistics were frequency, percentage, factor analysis, chi-squre, and cluster analysis. The major findings were followings: the teenager's housing lifestyles were categorized into the five patterns: the creative and impulsive type, the personal and private type, the economic and traditional type, the Western lifestyle-type, functional and achievement-orienented type. Teenagers in the low class of the functional and achievemental type demanded for the desk of the strong structure and materials, under 200,000 wons, and D furniture. Teenagers in the middle-high class of the personal and private type demanded for the desk of colorful and good design, 200,000-400,000 wons, and DS furniture. Teenagers in the high-low class of the Western lifestyle-type demanded for the desk of the famous trademark, 400,000-600,000 wons and S furniture. Teenagers in the middle-low class of the economic and tradition-oriented type demanded for the desk of the convinient and functional design, under 200,000 wons, and L furniture.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.10
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• pp.673-677
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• 2014

In this paper, thermal analysis of HDU (Heat Dissipation Unit) for infrared CCTV is performed by using SolidWorks Simulation (Thermal analysis) package, in order to change the part materials and HDU shape is optimized. Furthermore, HDU disperses the aggregated heat around the LED inside the housing. The junction temperature of infrared LED checked by HDU check was $65.83^{\circ}C$, $42.02^{\circ}C$, respectively. In addition, the Thermoelement by changing the shape of the HDU was possibly designed and equipped with. Comparison with simulation and prototype measurement results, without HDU model was $65.83^{\circ}C$, $61.99^{\circ}C$, respectively. In addition to with HDU model was $42.02^{\circ}C$, $39.01^{\circ}C$, respectively. Only HDU mounted into infrared CCTV is usable in the ordinary house or outdoors. Also HDU with thermal element, fan mounted into infrared CCTV is usable in a blast furnace workplace or high temperature workplace.

• Transactions of Materials Processing
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• v.13 no.7
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• pp.635-641
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• 2004

Today the specific outputs of modern supercharger DI diesel engine for passenger cars reach values exceeding 50kw/1. By development of the articulated piston, specific output of up to 70kw/1 are sought. In doing so, peak cylinder pressure increases from the current 14-16MPa to 18-20MPa. The Articulated piston was composed Al cast skirt part and steel forged crown part. We have the target fer the design of forging process and die of the steel forged crown part. The design parameters of the forging process of the piston were obtained by the forging industry experiences and our experimental data and analysis result of finite element simulation. Especially, the design parameter of preform in blocker die was decided by finite element simulation using numerical package DEFROM3D. And also we can verify the design parameter by conducting visio-plasticity test using plasticine material. When we compared the results of analysis and experiment, a metal flow and load curve showed good agreement. Through this research, we could design optimal preform shape of articulated piston for this supercharged DI diesel engine.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.2751-2755
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• 2016

Background: Melanoma, the most life-threatening type of skin cancer, is a malignant tumor initiating in melanocytes that rapidly metastasizes and causes death. Materials and Methods: In this retrospective study, samples were selected from patients' information files in our Cancer Institute in Tehran with a designed checklist. A total of 322 files were found from 2003 until 2012. Then the raw data were transferred to Statistical Package for Social Sciences (SPSS) software version 16 and additional analysis was performed by Students t-test. The important variables were considered according to the available information from history of pathology including age, gender, occupation, stage and location of tumor. Results: Our data showed that incidence of melanoma has been different in the studied 10-year period according to age. Also, incidence of melanoma was higher in men than women. It was more common in lower limbs. More commonly housewives among women and farmers among men were affected by melanoma. Conclusions: Taken together the descriptive data clarified general aspects of this disease for further screening and interventions.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.1
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• pp.115-129
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• 2019

This study aimed to develop methods for technical design education that can be intimately connected to the industrial field. For this, technical design jobs performed in the fields of the domestic and foreign fashion industries and their required competences were examined, and educational methods based on constructivism were proposed. Korean fashion technical designers' works were identified, and then the fashion technical designer's responsibilities and qualifications were collected and analyzed from global employment sites. On the basis of the collection and analysis, hands-on staff members and education experts were interviewed about required competences for the actual business and possible suitable methods for education. The results of research showed that in the case of the US, job systems and relevant duties for technical designers were clearly defined by clothing brands, whereas in Korea, businesses were systematized around vendors, not brands, and as a result the businesses of technical package composition and specification proposals were not performed properly. This study organized the contents of technical design education into fit development and specification, the composition of technical design packages, the evaluation and approval of samples, fit schedule management and fitting, block pattern setting and pattern correction, sewing specifications appropriate for styles and materials, grading, technical terms, and production management. As for the technical design education models, the cognitive apprenticeship model, resource-based learning, the problem-based and anchored model, and the problem-based and resource-based models were proposed.

• Journal of the Korean institute of surface engineering
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• v.52 no.3
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• pp.171-179
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• 2019

We have developed a numerical model to analyze flow dynamics and heat transfer characteristics of the cooling water in a circular rotating magnetron cathode by a moving boundary grid method realized in a commercial multiphysics package, CFD-ACE+. The numerical model is composed of a target, dual mass rotating cathode and cooling water connections. When the inlet and outlet of the cooling water are offset by the same distance from the rotation axis, the temperature at the center is higher by $50^{\circ}C$ at maximum. At 5 mm away from the target surface, the temperature profile showed typical center high characteristic. At heat input of 30 kW, the maximum temperature change of the cooling water hits $6^{\circ}C$ within 0.5 sec under 60 rpm. With a cooling water configuration of center in/edge out, the temperature of the center region of the target gets lowered. Within 100 seconds of plasma operation time, the cooling water temperature keeps getting higher.

• Nuclear Engineering and Technology
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• v.53 no.5
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• pp.1534-1539
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• 2021

This study reports on the dissolution behavior of SrO in LiCl at varying SrO concentrations from low concentrations to excess. The amount of SrO dissolved in the molten salt and the species present upon cooling were determined. The thermal behavior of LiCl containing various concentrations of SrO was investigated. The experimental results were compared with results from the simulated results using the HSC Chemistry software package. Although the reaction of SrO with LiCl in the standard state at 650 ℃ has a slightly positive Gibbs free energy, SrO was found to be highly soluble in LiCl. Experimentally determined SrO concentrations were found to be considerably higher than those present in used nuclear fuel (<2 g/kg). As Sr-90 is one of the most important heat-generating nuclides in used nuclear fuel, this finding will be impactful in the development of fast, simple, and proliferation-resistant heat reduction processes for used nuclear fuel without the need for separating nuclear materials. Heat reduction is important as it decreases both the volume necessary for final disposal and the worker handling risk.