• Journal of Power System Engineering
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• v.19 no.6
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• pp.12-18
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• 2015

Austenitic stainless steels generally experience the occurrence of chromium-depleted zones at the boundaries, known as sensitization, caused by the carbide precipitation that takes place due to a welding process or heat treatment. Normally, the depleted zones become the focus of the intense corrosion. In this study, the Cr-free organic/inorganic hybrid solution was developed, and the artificially degraded STS316S and STS347H with the solution-coating investigated the corrosion resistance by salt spray test. Both the OIBD-1 and OIBD-2 solutions improved the corrosion resistance of STS310S and STS347H. The corrosion resistance with the OIBD-1 solution was better than that of OIBD-2 solution. Additionally, Both solutions have been proven excellence in adhesion ability, boiling water resistance and flexibility. However, a problem of rubbing after the boiling was found out to be overcome.

• Tribology and Lubricants
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• v.11 no.5
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• pp.162-171
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• 1995

The application of reciprocating engine crankshaft bearings is of particular importance and interest among the plain bearing, not only because the sheer volume of intemal combustion engines now produced, but because the severe operating conditions they are subjected to. Demands for better performances of crankshaft bearings have provide an important impetus in the development of bearings and bearing materials. As engine design progresses toward higher outpt and higher efficiency, crankshaft bearings must perform under more seveve operating conditions. Higher load, temperature, and speed as well as lower viscosity oil are applied to the bearing sysem, resulting in a smaller minimum oil film thickness. This means more solid-solid contact between the shaft and bearing, and the bearing is exposed to more danger of seizure. Some engines may experience bearing seizure problems. However, understanding about the seizure behavior and mechanism is far from being enough. Seizure resistance of a bearing-shaft system will be affected by the properties of the shaft and bearing, especially their materials and surface texture. Commonly used engine bearing materials include Al-Pb-Si, Al-Sn-Si, Al-Sn, and Cu-Pb with Pb-Sn-Cu overlay. These materials have very different properties. They showed different behaviors dering seizure tests and seizure may occur with different mechanism for different bearing material. Shaft materials also affect the seizure resistance of the system. Surface texture of the bearing and shaft have apparent effects on the lubrication and solid-solid contact pattern, and therefore will affect the seizure behavior of the system. Bearings and shafts which are made of different materials and have different surface textures have been tested and analyzed. Their effects on seizure resistance are discussed and possible seizure mechanisms for different beatings are presented in this paper.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.6
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• pp.2566-2574
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• 2013

This study performed a focus group interview(14 people) on food-service staffs, dieticians, and housewives to develop a small multi-function oven for rice flour. The interviewees have experienced rice flour cooking and oven at home or food-service business. The interviewees have not used commercial ovens on a daily basis for several reasons, such as the absence of understanding rice flour, lack of various recipes with rice flour and inconvenience of the oven. This study suggests of design, user experience, functional characteristics, color and so on relating to a small multi-function oven to the customers.

• Fashion & Textile Research Journal
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• v.22 no.2
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• pp.209-221
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• 2020

Recently, following the commercialization and market entry of smart clothes with diverse functions, smart clothes have been changing from technology-centered products to user-centered products. However, the analysis of consumer demand centered on actual commercialized products is lacking. Therefore, this study classified commercialized smart clothes by function and analyzed the demand and requirements of smart clothes according to sports/outdoor clothes consumption behaviors. As a result, consumers were classified according to their sports/outdoor clothes consumption behaviors into an outdoor leading group with high consumption propensity, an outdoor pursuit group with medium consumption propensity, and an outdoor following group with low consumption propensity. Among the commercialized smart clothes, those with a heartbeat measuring function, those with a heating function, and those with a light-emitting function were presented and demand analysis was conducted. According to the results, the outdoor leading group and the outdoor pursuit group had higher levels of awareness, preference, and purchase intentions than the outdoor following group. In addition, the outdoor leading group showed the highest level of purchase price acceptance while the outdoor following group showed the lowest level of purchase price acceptance. However, this study has a limitation that the acceptance for smart clothes were analyzed with consumers who had experience in sports outdoor clothes consumption. Therefore, in future, studies will be conducted with a wide range of consumers.

• School Mathematics
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• v.11 no.2
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• pp.281-299
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• 2009

In this paper, we show how dynamic manipulation environments can be integrated in the mathematics curriculum by presenting some pedagogical tasks manufactured by dynamic manipulation. These examples are composed to produce meaningful definitions through inductive experiments, to strengthen the thinking ability on continuity through the visualization, to make mathematics through investigation and finding, and to strengthen the ability of posing and generalizing problems. Through these examples students can observe the process of how mathematics is being invented, and they can experience how to solve mathematical problems using physical experiments in dynamic manipulation environments. When integration of dynamic manipulation into the teaching and learning of mathematics is applied, some difficulties can come out. To resolve such difficulties, a teacher must play the role of a co-worker of students in addition to the role of a scaffolder, coach, or close listener.

• Health Policy and Management
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• v.23 no.3
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• pp.210-223
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• 2013

Backgrounds: Escalating pharmaceutical expenditure has threatened the sustainability of National Health Insurance system in Korea. Generic medicines allow patients to access safe, effective, high-quality medicines at low cost, thus insurers could achieve significant financial savings by promotion of generics, if they are priced much lower than the originator. The purpose of this study was to review generic pricing as well as promotion policies in other countries and assess the implication of those policies. Methods: We reviewed the main measures adopted by the developed countries such as Austria, Belgium, Denmark, Finland, France, Germany, Italy, Japan, Netherlands, Norway, Sweden, United Kingdom, especially in countries where governments are the largest third-party payers or insurance finance resource is the national health insurance. Results: The foreign countries's experience with generic medicine policy shows that demand-side policies such as physician budgets, international nonproprietary name prescribing, generics substitution, patients co-payment as well as supply-side policies relating to pricing and reimbursement seems to play a critical role in developing the generic medicines market. Conclusion: Various strategy should be implemented to promote generic drug use.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.5
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• pp.19-28
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• 2016

This study was to design the optimal locations of the water level monitoring to quantify the agricultural water use in irrigation area supplied from an agricultural reservoir. In most of agricultural areas without TM/TC (Tele-Monitoring and Tele-Control) or monitoring network, irrigation water have been supplied on conventional experience and agricultural reservoir have been operated based on the operating simulation results by HOMWRS (Hydrological Operation Model for Water Resources System). Therefore, this study quantified the amount of agricultural water use in an irrigation area (Musu Reservoir, Jincheon-gun) by establishing water level monitoring network and analyzed the agricultural water saving effect. According to the evaluation of the economic values for water saving effect, the saving agricultural water of 1.7 million ton was analyzed to have economic values of 0.85 million won as water for living, and 1.78 million won as water for industrial use. It is identified to secure economic feasibility of the new water monitoring network by establishing one monitoring point in the entrance, irrigation area and endpoint through the economic analysis.

• Progress in Superconductivity and Cryogenics
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• v.16 no.4
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• pp.49-52
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• 2014

REBCO coated conductor (CC) tapes with superior mechanical and electromechanical properties are preferable in applications such as superconducting coils and magnets. The CC tapes should withstand factors that can affect their performance during fabrication and operation of its applications. In coil applications, CC tapes experience different mechanical constraints such as tensile or compressive stresses. Recently, the critical current ($I_c$) degradation of CC tapes used in coil applications due to delamination were already reported. Thermal cycling, coefficient of thermal expansion mismatch among constituent layers, screening current, etc. can induce excessive transverse tensile stresses that might lead to the degradation of $I_c$ in the CC tapes. Also, CC tapes might be subjected to very high magnetic fields that induce strong Lorentz force which possibly affects its performance in coil applications. Hence, investigation on the delamination mechanism of the CC tapes is very important in coiling, cooling, operation and design of prospect applications. In this study, the electromechanical properties of REBCO CC tapes fabricated by reactive co-evaporation by deposition and reaction (RCE-DR) under transversely applied loading were investigated. Delamination strength of the CC tape was determined using the anvil test. The $I_c$ degraded earlier under transverse tensile stress as compared to that under compressive one.

• 한국지구물리탐사학회:학술대회논문집
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• 2007.06a
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• pp.285-290
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• 2007

Electrical and electromagnetic methods were widely applied to survey of civil engineering, environment site assessments and maintenance of underground structures in Korea. Electro-physical properties measurements of soil and rock are necessary in order to quantitatively estimate the ground from these survey results. A few geotechnical researcher groups have been simplified measurement system of the electro-physical properties, which was intermittently operating by the necessity. Recent strong concern about $CO_2$ underground storage and development of gas hydrate projects have urged many advanced countries. The electro-physical properties estimation of the deep object stratum is very importance for basic information of these research. So, advanced countries have a high-end measurement system with high temperature(200 degrees) and pressure(300 MPa), also they have been a lot of experience and know-how on the electro-physical properties measurement.

• Nuclear Engineering and Technology
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• v.41 no.4
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• pp.545-548
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• 2009

Korean utility has utilized a Periodic Safety Review (PSR) that assesses the cumulative effects of plant aging, modifications, operating experience, technical developments, and site characteristics since 2000. In particular, the assessment and management of plant aging is one of the major areas in PSR. It includes identification of critical Systems, Structures, and Components (SSCs) for aging, assessment of aging effects, and implementation of aging management programs. Since the PSR system was introduced based on the atomic energy acts and related laws, PSRs of eight sets for 12 Nuclear Power Plants (NPPs) that have been operating more than 10 years have been completed. PSRs of two sets for 4 NPPs are currently being carried out. The utility has confirmed that domestic NPPs have been operated safely through these PSRs and have implemented the follow-up corrective activities to increase the nuclear safety. In this paper, the status of PSR implementation is discussed and improvement programs to conduct PSR follow-up corrective activities efficiently for NPPs are suggested based on experiences with aging assessments.