• International Journal of Advanced Culture Technology
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• v.6 no.2
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• pp.9-15
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• 2018

The purpose of this study was to assess risk indicators of depressive symptoms such as demographic, socio-economical domains (age, gender, marital status, education, child, religion, income, health, friendship) and personality domains (neurotic personality, self-esteem and life goal attitude) of community dwelling elderly persons. A total of 300 community-residing elderly participants aged 65+ in a metropolitan city in Korea, were recruited for this interview survey. The interview covered demographic and socio-economic characteristics, and administration of the 20-item Korean Version of CES-D, the 10-item Self-esteem, the 19-item Neuroticism and the 10-itm Goal Instability scale. The prevalence of significant depressive symptoms (CES-D scale >= 21) was 31%. Logistic regression analysis showed high risk for depression was associated with high neuroticism, less intimate friendship, high goa1 instability, and childlessness, respectively in the order of significance. Factors in the personality domains were more strongly associated with depressive symptoms than factors in the socio- economical domains. Both cultural and universal meaning of the findings was discussed with regard to intervention.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.7
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• pp.407-413
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• 2003

Before expanding of distribution automation application to distribution network, we must examine whether there are economical effect. Investment expense for distribution automation can be divided into facility investment expense, maintenance expense, communication expense, investment expense etc. Effect of distribution automation can classify by effect that can convert into money and effect that can not convert into money. Representative effect is outage time decrease effect, distribution line loss decrease effect, main transformer upload effect, distribution line upload effect, work environment improvement effect of lineman and so on. This paper studied economical effect and break-even Point for investment expense by using data that acquire in KEPCO's distribution network.

• Proceedings of the Korea Database Society Conference
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• 1997.10a
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• pp.96-113
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• 1997

The purpose of this paper is to make a study on the characterization of multimedia phenomena and to analyse the tendency of multimedia services and market. At first, various definitions of multimedia and the basis of multimedia services are analysed and evaluated from the point of economical, technical, and practical views. After that the expert survey to estimate an accurate tendency of multimedia services in Germany is analysed and the state of development in the field of multimedia database in Korea is investigated. Upon the results of these analysis and evaluation, the economical and managerial interests are described.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.592-595
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• 2009

In recent years, geothermal heat pump (GHP) systems have become increasingly popular for heating and cooling in buildings. The Standing Column Well (SCW) method is one of the most efficient GHP system. Because it use groundwater for heat transfer material. In SCW systems, water is re-circulated between the well and the building (heat pump). It is only a short time since this method has been applied in domestic. So we have to refer to the developed countries' guides and manuals of SCW. In this paper, several design and construction points of SCW method are filed. We used real operation data of SCW system at Chong-Ju Univ. site for economical efficiency analysis. As a result, the payback period of Chong-Ju Univ. site is calculated at 7.23 years.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.261-264
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• 2007

In this study, the consolidation and casting processes of fine Si powders, by-products of making high purity Poly-Si rods in the current method, were systematically investigated for use as economical solar-grade feedstock. Morphology, size, and contamination type of the poly-Si fine powders were inspected by combined analysis of SEM, particle size analyzer, and FT-IR. Poly-Si powder compacts were tried to fabricate by a consolidation process without a binding agent and then their density ratio and strength were evaluated. Finally, the electrical resistivity of the specimens prepared by an electromagnetic casting method was examined for purity assessment.

• Journal of Ocean Engineering and Technology
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• v.5 no.1
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• pp.64-70
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• 1991

The design theory of roller gate has been systematized laying more emphasis on practical formulas than theoretical ones and the design procedure of the existing gate facilites is reviewed and analyaed on economical viewpoint and safety factor. The design theory of timoshenko, the thechnical standards for hydraulic gate and penstock of Japan, and the design standards for waterworks structures of Germany are applied to the study of optimal design of a gate leaf. In this study, gate leaf which is now being operated for water control at the seadike, estuary dam and reservoir dam are adopted as a mode, and a new design method by the computer is proposed through the variation of design elements within practical ranges. As a result, safety factor and economical design can be made by using T-beams to the horizontal and vertical beam of the gate leaf instead of H-beams used in the existing seadike roller gate at Asan, and total weight of gate leaf is reduced by the present optimization.

• Journal of the Korean Society for Railway
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• v.8 no.5
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• pp.444-453
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• 2005

The safety evaluations of railway wheelsets make use of the static fracture toughness obtained in ingot materials. The static fracture toughness of wheelset materials has been extensively studied by experiments, but the dynamic fracture toughness with respect to wheelset materials has not been studied enough yet. It is necessary to evaluate the characteristics of the fracture mechanics depending on each location for a full-scale wheelset for high-speed trains, because the load state for each location of the wheelset while running is different the contact load between the wheel and rail, cyclic stress in the wheel plate, etc. This paper deals with the fracture toughness depend on load rates. The fracture toughness depending on load rate data shows that once the downward curve from quasi-static values was reached, subsequent values showed a slow increase with respect to the impact velocity. This means that dynamic fracture toughness should be considered in the design code of the wheelset material.

• Journal of Sericultural and Entomological Science
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• v.18 no.2
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• pp.95-100
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• 1976

Utilization of the various cocoon beds were evaluated by raising the silkworm variety "Seul-ak${\times}$Soyang"according to cocoon quality produced in spring of 1969: Rotary cocoon bed, improved cocoon bed, grima cocoon bed, wood framed straw rope cocoon bed, and pine cocoon bed. In addition the economical analysis was made on the basis of cocoon price in spring of 1976. 1. The Rotary cocoon bed has economically much advantages in many ways; easy cocoon collection and percentage of best cocoon, percentage of cocoon shell, reelability and percentage of raw silk. It may give 8100 won for an extra income per box and increase by raising higher yielding variety. 2. The grima cocoon bed is superior to the wood framed straw rope cocoon bed, and the pine cocoon bed and it is comparatively easy set-up even though it is inferior to the improved cocoon bed in many characters.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.198-199
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• 2017

In this paper, the applicability of PHC piles to replace Myanmar local piles were evaluated. In Myanmar, based on the size of the building, foundation design and field applications are carried out using bored pile and square pile. As a result of the analysis, the application of PHC pile is more economical than conventional bored pile or square pile which was applied in the high rise (17-story) and middle story (12-story) buildings. However, in the low - rise (8-story) building, the application of the existing square piles was found to be more economical than PHC pile.

• Journal of Hydrogen and New Energy
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• v.18 no.2
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• pp.216-223
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• 2007

The present carbon-based energy system will not last long due to its environmental and economical drawbacks. Hydrogen energy attracts more attention recently and seems to have large ripple effect on economy providing its technical, environmental and economical problems are solved. This paper analyses the situation changed from fossil to non-fossil energy system and the R&D policies of advanced countries by reviewing the world energy status and the energy policy of foreign countries. Finally, the R&D strategy of hydrogen energy technology was developed through analyzing the present states of energy research policy and programs of major countries.