• Journal of computational fluids engineering
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• v.22 no.1
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• pp.51-58
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• 2017

A penalized VIC method offers an efficient hybrid particle-mesh algorithm to simulate an incompressible viscous flow passing a solid body in an infinite domain. In this manner, the computational domain needs to be restricted to a relatively small region to reduce computational cost which would be very high in case of using a large domain. In this paper, we present how to dispose of far-field particles to avoid an unnecessarily large computational domain. The present approach constraints expansion of the domain and thus prevents the incremental computational cost. To validate the numerical approach, a flow around an impulsively started sphere was simulated for Reynolds numbers of 100 and 1000.

• Journal of Technology Innovation
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• v.8 no.2
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• pp.97-117
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• 2000

TOEM strategy is widely used in Japan and Korea because of the diverse advantages such as cost sharing, technology transfer, equipment lease and base technology acquisition between parent company and OEM supplier. There are, however, some disadvantages that (1)OEM suppliers are likely to be reactive to environmental changes and (2) may have difficulty in building competitive position and long-term growth. When the parent company relocates its plant to foreign countries to achieve lower labor cost or to enhance value added this change will affect directly the OEM supplier's outcome. The parent company's divestiture from existing businesses will also affect the OEM supplier. For the OEM supplier to survive in face of these strategic changes it must enter the new countries with the parent company. Alternatively, the OEM supplier must actively diversify its technologies based on its core capabilities of existing product and process technologies and seek new business arenas. The strategy of aligning its businesses with the parent company's new business strategy allows the OEM supplier to share the new market while it requires the OEM supplier to develop core capabilities. In Korea many small and medium sized OEM suppliers are dependent on a few large companies. For the industry structure in Korea where industry concentration is extremely high OEM suppliers should move away from the past strategy, where they are dependent on the parent company's low profitability businesses. They should actively enter new businesses for which parent companies enter to achieve long-term growth.

• Ocean and Polar Research
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• v.21 no.2
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• pp.117-126
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• 1999

To meet increasing needs for environmentally sustainable management of coastal area, there has been compelling pressure to establish a cost-effective and long-term coastal water quality (CWQ) monitoring system. A remote CWQ monitoring system, STAMP, has been developed and is in operation along the route between Kyema harbor and Anma Island in the southwestern coastal area of Korea. STAMP uses a PCS phone as a telemetry unit to transmit acquired data for monitoring general water quality parameters, and a routinely operating coastal passenger ship or car ferry. STAMP has various merits of low-cost operations; long-term monitoring with secure instrumentation; and stable real-time telemetry of acquired data with-out the loss and noise. It is expected that the system will serve as a very useful tool in the CWQ managing programs of Korea taking the advantage of many coastal passenger ships in various routes including the ships departing from the coastal industrial cities. The acquired data compiled on suspended surface sediment concentrations (SSSC) will be also valuably helpful in understanding the sediment budget across the routes of the vessel.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.878-882
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• 1996

This paper discusses the definition and concepts, approach methodologies, capable application areas in electricity business, and tentative calculation of avoided generation costs based on the Korea's official long-term generation expansion plan. The objective to evaluate avoided costs of a resource is to supply decision makers with the breakeven cost of a targeting avoided resource. For the evaluation of avoided costs of the Korea's generation system, we consider the pseudo-DSM option which has 1,000MW peak savings, load factor with 70 percent, and life-time With 25 years as the avoided resource. The DSM resource can save the fuel and capacity additions of a electric utility during its life time. The capacity and fuel savings are evaluated from the two different cashflows with and Without the DSM option, which are generated on the basis of the generation system optimization model(WASP-II), independently. The breakeven kWh costs of the DSM option over this 25-year period is projected to be 34.1[won/kWh], which is composed of generation-capacity and fuel avoided costs with 101.139[won/kW] and 17.6[won/kWh], respectively.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.3
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• pp.237-248
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• 2017

The estimation method of economical leakage management target utilized upon planning business for improvement of revenue water ratio in South Korea is presented and applicability of methods developed in this study is assessed through application on site. With a consideration of revenue water ratio in application target area, estimation method of long-term economical leakage management target is applied. Three leakage reduction methods such as replacement of residual aged pipe, leakage investigation and restoration and water pressure management are applied with a consideration of characteristics of site. Due to difficulty of obtaining data, analysis of cost/benefit by leakage reduction methods is performed by applying method of leakages estimation equation among statistical methods. As a result of application, revenue water ratio corresponding to long-term economical leakage management target is 91.6 %.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.65-67
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• 2011

It is necessary to the development of the best maintenance system for applying the long-term maintenance plan using the cost breakdown structure in the educational facilities. This study developed the cost breakdown structure for the best maintenance system using the delphi method. For the convenience of maintenance, the maintenance cost breakdown structures are separated into building exterior wall, building inside wall, electric installation, heating installation and outdoor facilities. And these results atomized in each parts. And this study constructed the cost breakdown structure to maintenance's practicality and effectiveness through the expert analysis.

• Journal of the Korea Institute of Building Construction
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• v.15 no.2
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• pp.209-215
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• 2015

This study was conducted to analyze the actual utilization rate of the deposit for defect repair of apartment complexes and its influential factors. We analyzed the data on enforced defect deposit cases by using one-sample t-test, Pearson's correlation analysis, and simple linear regression analysis. The difference between the deposit amount specified and the enforcement amount actually disbursed was found to about 0.51%. The change rates for short-term costs amounted approximately to $839KRW/m^2$ and 130,000 KRW/household per year, and those for long-term costs were $647KRW/m^2$ and 123,207 KRW/household per year. The results warrant the need for further research on establishing a deposit amount based on actual statistical data.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.7 no.2
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• pp.125-132
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• 2013

This research is focused on improvement of satisfaction of the assistive products, which is used by long term care elderly people. We investigated 1,200 long-term cared elderly and this survey was conducted by care-giver. The average satisfaction of the assistive products are in convenience 3.43, in function and effectiveness 3.33, in safety and secure 3.29 and in adequacy cost compared to effectiveness 2.69. Total average satisfaction of utilization is 3.19. Satisfaction with the use of assistive products in using motivation does not show a statistically significant difference, but in selection factors is a difference to be statistically significant. In conclusion, expert-consulting should be enhanced for the improvement of satisfaction and the provision of assistive products should be expanded in long-term care insuance schemes. Also, the rational index and evaluation method of the satisfaction of the assistive products should be developed through continuous studies.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.484.2-484.2
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• 2014

There are many efforts to improving the power conversion efficiencies (PCEs) of dye-sensitized solar cells (DSCs). Although DSCs have a low production cost, their low PCE and low thermal stability have limited commercial applications. This study describes the preparation of a novel multifunctional polymer gel electrolyte in which a cross-linking polymerization reaction is used to encapsulate $TiO_2$ nanoparticles toward improving the power conversion efficiency and long-term stability of a quasi-solid state DSC. A series of liquid junction dye-sensitized solar cells (DSCs) was fabricated based on polymer membrane encapsulated dye-sensitized $TiO_2$ nanoparticles, prepared using a surface-induced cross-linking polymerization reaction, to investigate the dependence of the solar cell performance on the encapsulating membrane layer thickness. The ion conductivity decreased as the membrane thickness increased; however, the long term-stability of the devices improved with increasing membrane thickness. Nanoparticles encapsulated in a thick membrane (ca. 37 nm), obtained using a 90 min polymerization time, exhibited excellent pore filling among $TiO_2$ particles. This nanoparticle layer was used to fabricate a thin-layered, quasi-solid state DSC. The thick membrane prevented short-circuit paths from forming between the counter and the $TiO_2$ electrode, thereby reducing the minimum necessary electrode separation distance. The quasi-solid state DSC yielded a high power conversion efficiency (7.6/8.1%) and excellent stability during heating at $65^{\circ}C$ over 30 days. These performance characteristics were superior to those obtained from a conventional DSC (7.5/3.5%) prepared using a $TiO_2$ active layer with the same thickness. The reduced electrode separation distance shortened the charge transport pathways, which compensated for the reduced ion conductivity in the polymer gel electrolyte. Excellent pore filling on the $TiO_2$ particles minimized the exposure of the dye to the liquid and reduced dye detachment.

• Health Policy and Management
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• v.19 no.1
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• pp.81-96
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• 2009

The expansion of long-term care hospitals (LTCHs) is expected to contribute to meeting the long-term care needs of the elderly with chronic diseases in a rapidly aging society. It is also expected to increase efficiency of health resource use and decrease elderly health expenditures by transferring patients from acute care hospitals (ACHs) to LTCHs. This study aimed to empirically examine how the expansion of LTCHs had influences on the length of hospitalization of the elderly in ACHs. Panel regression analysis was employed as an analytic tool using data of the National Health Insurance and the National Statistical Office from 2002 to 2006. The expansion of LTCHs was measured as location quotient (LQ) of LTCHs, denoting the share of LTCHs in a large city or province relative to the share of LTCHs at the national level. In addition, per capita GRDP (gross regional domestic product) and the proportion of population over 65 were included as control variables. The main findings are as follows. First, it was observed that LQ of LTCHs showed a statistically significant negative association with the length of hospitalization of the elderly in ACHs. Second, the negative correlation was evident among general hospitals with over 100 beds while it was not among hospitals with less than 100 beds. Third, LQ of LTCHs had more influences among the elderly over 85. In conclusion, the expansion of LTCHs seems to contribute to decrease in the inpatient cost of the elderly in ACHs and to increase efficiency in the utilization of health resources.