• Nuclear Engineering and Technology
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• 제47권6호
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• pp.700-711
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• 2015

Sodium-cooled fast breeder reactors use liquid sodium as a moderator and coolant to transfer heat from the reactor core. The main hazard associated with sodium is its rapid reaction with water. Sodium-water reaction (SWR) takes place when water or vapor leak into the sodium side through a crack on a heat-transfer tube in a steam generator. If the SWR continues for some time, the SWR will damage the surface of the defective area, causing it to enlarge. This self-enlargement of the crack is called "self-wastage phenomena." A stepwise numerical evaluation model of the self-wastage phenomena was devised using a computational code of multicomponent multiphase flow involving a sodium-water chemical reaction: sodiumwater reaction analysis physics of interdisciplinary multiphase flow (SERAPHIM). The temperature of gas mixture and the concentration of NaOH at the surface of the tube wall are obtained by a numerical calculation using SERAPHIM. Averaged thermophysical properties are used to assess the local wastage depth at the tube surface. By reflecting the wastage depth to the computational grid, the self-wastage phenomena are evaluated. A two-dimensional benchmark analysis of an SWAT (Sodium-Water reAction Test rig) experiment is carried out to evaluate the feasibility of the numerical model. Numerical results show that the geometry and scale of enlarged cracks show good agreement with the experimental result. Enlarged cracks appear to taper inward to a significantly smaller opening on the inside of the tube wall. The enlarged outer diameter of the crack is 4.72 mm, which shows good agreement with the experimental data (4.96 mm).

• 한국해양공학회지
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• 제35권3호
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• pp.191-202
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• 2021

Studies on very large offshore structures are increasing owing to the development of deep sea, large-scale energy generation using ocean resources, and so on. The enlargement of offshore structures makes the hydroelastic effect and low natural frequency related responses important. Numerical analyses and model tests for hydroelastic and higher-order springing responses of fixed cylindrical structures are conducted in this study. The panel methods with and without the hydroelastic effect with shell elements, and the Morison analysis method with beam elements are applied. To observe the hydroelastic effect for structural strength, two structures are considered: bottom-fixed cylindrical structures with high and low bending stiffnesses, respectively. The surge motions at the top of the structure and bending stresses on the structure are observed under regular and irregular wave conditions. The regular wave conditions are generated considering the ratios of the cylindrical outer diameter to the wave lengths, and keeping the wave steepness constant. The model tests are performed in the three-dimensional ocean engineering basin in the KRISO (Korea Research Institute of Ships and Ocean Engineering). From the numerical and experimental results, in which the hydroelastic responses are only observed in the case of the structure with a low bending stiffness, it is confirmed that the hydroelastic responses are highly dependent on the structural stiffness. Additionally, the higher-order phenomenon on the specified wave condition is analyzed by observing the higher-order springing responses when the incident wave frequency or its multiples with the high wave height coincides with the natural frequency of the structure.

• 대한본초학회지
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• 제37권1호
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• pp.11-18
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• 2022

Objectives : Green gram (mung bean) has a cold nature and has been known to detoxify against various side effects that belong to hot in nature. In particular, since it has the effect of detoxifying fever and detoxification to treat swelling, it was also used externally to treat febrile dermatological diseases such as erysipelas and rubella. This study was designed to determine whether green gram exhibits anti-inflammatory effects on contact dermatitis in mice. Methods : We investigated the effects of green gram extract (70% ethanol extract) on skin lesion, skin thickness and weights, melanin and erythema index and spleen body weight ratio in mice with contact dermatitis induced by repeated application of 1-Fluoro-2,4-dinitrobenzene. Results : Topical application of green gram extract ameliorates skin lesions of contact dermatitis such as scale and roughness induces by 1-Fluoro-2,4-dinitrobenzene. green gram extract also suppressed enlargement of skin thicknesses and weights significantly. In addition, green gram extract treatment also lowered erythema index significantly compared to those in the control group. In the histopathological observation, green gram extract prevented epidermal hyperplasia and hyperkeratosis in inflamed tissues. Finally, green gram extract did not affect changes in body weights and the spleen body weight ratio, unlike dexamethasone, which significantly prevented body weight gain and lowered the spleen body weight ratio. Conclusions : These results imply that green gram, which is known to have a detoxifying effect in Korean medicine, can be used in the treatment of contact dermatitis.

• 수산경영론집
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• 제16권1호
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• pp.31-54
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• 1985

The mutual credit of Fisheries Cooperatives is reciprocal financing bring overs and shorts to settlement themselves by filling each other's needs among feeble fishermen economically. The spread of mutual credit through Fisheries Cooperatives reduces private loan dependence and private loan interest rate at fishery village, and that fills up policy financing being restricted by working scale. And seeing movement side of Fisheries Cooperatives, it has done an under board to settle self-supporting foundation of primary fisheries cooperatives early. The mutual credit deposit shows about 53 times increase past an interval of a ten years. This increase rate is an epoch-making record being unparalleled in other banking facilities except Fisheries Cooperatives. Then being unparalleled increase rate, time and savings deposits increase has been contributed a great deal than demand deposits. Thinking important function factors as mutual credit growth, we can classify interior and exterior factors. The exterior factor is income of fishery household in some measure, interior factors are the high deposits interest rate and the enlargement of facilities organization. As these, they have been in a better factors, also have been a restriction factors. The restriction factors are conflict cancellation between mutual credit and them bring into existence a village vault, mutual savings and finance companies, private finance. For the sake of continuance growth rate in mutual credit as past, we should eliminate restricted factors in growth. On the other hand the better factors in growth should be act upon affirmation side continually. Consequently under circumstances not to an amicable settlement bring the fisheries fund demand as policy financing, we should do continuous and sound development of fisheries financing by means of putting in good order of fisheries cooperatives mutual credit. Surveying a problem from these viewpoints, when we study more deep and a full into a subject about growth project of mutual credit, we think to expect continuous growth in mutual credit of Fisheries Cooperatives.

• 산업공학
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• 제25권1호
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• pp.52-63
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• 2012

Up-to-date enlargement of the scale of global outsourcing has brought about the need of systematic and efficient tools for competitive supplier discovery located in various areas. A web-based business supporting system, referred to as Excellent Manufacturer Scouting System(EMSS), is being developed to serve core business functions including supplier discovery, negotiation, and collaboration between overseas buyers and domestic suppliers throughout the process of supply chain formation. In this paper, a supplier assessment model devoted to evaluation of core manufacturing capability is proposed by targeting small and medium sized mold companies. The assessment model will eventually be loaded to EMSS. Even if many well-designed models for supplier assessment have been presented in literature, most of them limit the evaluation criteria to somewhat general information on a given supplier, such as cost, delivery time, quality, rather than core manufacturing capability itself. This research is pioneering work on supplier assessment from the viewpoint of manufacturability. The proposed assessment model classifies assessment indices into six criteria, which have been drawn by intensive survey and analysis of the mold industry. Actual assessment indices for each criterion are also presented along with an exemplary evaluation result.

• 한국축산시설환경학회지
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• 제6권1호
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• pp.1-14
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• 2000

The structural and environmental characteristics of typical pig houses in different growth phases were surveyed and analyzed. Based on the data for thirty nine selected farms in four provinces, Jeonbuk-do, Jeonnam-do, Gyeongbuk-do, and Gyeongnam-do, in the southern provinces, Korea, the goal is to eventually establish standard pig houses of sow and litter, nursery pigs, and growing-finishing pigs. The survey included farm scale, production specialization, structural dimensions of the houses and their ventilation systems, cooling and heating systems, and floor and pit systems related to manure collection. The survey showed 90∼98% of growing-finishing pig houses adopted the sidewall curtain systems. The sidewall curtain systems, although popular, is not well insulated which leads to excessive heating costs in winter. Regarding flooring and manure collection system of the house, 23∼35% of growing-finishing houses installed scraper systems with concrete-slat floors in Gyeongsang provinces while 52∼78% did in Jeolla provinces. The cause of a large variance in flooring between tow regions could not be academically pinpointed, rather it could be attributed to the advice of neighbors who leads local pig production circle. A general trend toward enlargement and enclosure of pig houses for all growth phases was gaining popularity in most regions in recent years. A steady shift to multisite operation from continuous operation was also observed to prevent a disease transfer. The structural design of a standard pig house with its environmental control systems including ventilation and heating/cooling system was suggested for further validation study. In-depth analysis of the survey data is presented in the Results and Discussion section.

• 한국항해항만학회지
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• 제29권6호
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• pp.529-536
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• 2005

최근 들어 초대형 선박에 대한 논의가 활발해진 가운데 선사들은 선박 대형화에 의한 규모의 경제 효과를 꾸준히 추구하고 있다. 기술과 경제성이 보장되는 한 당분간 이러한 선박 대형화의 추세는 지속될 전망이다. 선박대형화에 따라 거주공간의 위치변화에 대한 필요성이 조심스럽게 제기되고 있다. 본 논문은 초대형 컨테이너선의 거주 공간 재배치에 따른 경제성 평가 분석에 관한 내용을 다루었다. 선박의 초기 설계 단계에서, 도면 생성의 보완과 검증을 통하여 거주구역과 엔진실의 공간을 분리하는 제안을 하였다. 그에 관한 장단점을 분석하고, 실현 가능성 여부를 경제성 평가 분석을 통해 검토하였다. 경제성 평가 방법을 위한 목적함수는 요구운임지수를 사용하였다. TEU 증가에 의한 경제성을 전망하고, 이러한 공간 재배치에 따른 조선소와 선주의 경제성 평가를 분석하여 선적 개수의 증가에 따른 경제성 전망을 제시하였다.

• 대한안전경영과학회지
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• 제19권1호
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• pp.63-71
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• 2017

As the demand for automation (or autonmation) or clean workplace has grown, the interest in the knowledge and skill regarding safety is rising in manager duty. Moreover, the importance of severity rate of injury has increased due to the enlargement of industry scale, even safety management area has developed. Thus, it is important that production managers, the core of the line process, realize the safety in their production line, even if a safety manager acts as a staff. However, in the duty oriented National Competency Standard (NCS), the education about the safety duty of production management part is insufficient. According to NCS, it is calculated production managers receive only 6.7% of whole safety education regarding the duty related the safety management for production manager in mechanical industry. However, the ability in safety is more demanded from production managers as the concept of "production and safety" turns into the concept of "production with safety". And then in this paper, we will compare and analyze the safety management duty in Korean NCS and the safety management duty in State Leaders Connecting Learning to Work in US manufacturing industry, in terms of the duty of the production manage in mechanical industry (05). And, we will develop the safety duty education system for production manager, by classifying the safety education in domestic mechanical industry into knowledge education, skill education, and attitude education with using AHP(Analytic Hierarchy Process).

• Journal of Korean Neurosurgical Society
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• 제54권3호
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• pp.164-174
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• 2013

Objective : The aim of this study was to determine 30-day mortality and 6-month functional recovery rates in spontaneous intracerebral hemorrhage (S-ICH) patients undergoing hemodialysis treatment for end-stage renal disease (ESRD), and to compare the outcomes of these patients and S-ICH patients without ESRD. Methods : The medical records of 1943 S-ICH patients from January 2000 to December 2011 were retrospectively analyzed with focus on demographic, radiological, and laboratory characteristics. Results : A total of 1558 supratentorial S-ICH patients were included in the present study and 102 (6.5%) were ESRD patients. The 30-day mortality of the S-ICH patients with ESRD was 53.9%, and 29.4% achieved good functional recovery at 6 months post-S-ICH. Multivariate analysis showed that age, Glasgow Coma Scale (GCS) score, pupillary abnormality, ventricular extension of hemorrhage, hemorrhagic volume, hematoma enlargement, anemia, and treatment modality were independently associated with 30-day mortality in S-ICH patients with ESRD (p<0.05), and that GCS score, volume of hemorrhage, conservative treatment, and shorter hemodialysis duration was independently associated with good functional recovery at 6 months post-S-ICH in patients with ESRD (p<0.05). Conclusion : This retrospective study showed worse outcome after S-ICH in patients with ESRD than those without ESRD; 30-day mortality was four times higher and the functional recovery rate was significantly lower in S-ICH patients with ESRD than in S-ICH patients without ESRD.

• 한국축산시설환경학회지
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• 제5권1호
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• pp.1-15
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• 1999

The structural and environmental characteristics of typical pig houses in different growth phases were surveyed and analyzed. Based on the data for thirty six selected farms in four provinces, Gyonggi-do, Gangwon-do, Choongnam, and Chonbook, in Central Korea, the goal is to eventually establish standard pig houses of sow and litter, nursery pigs, and growing-finishing pigs. The survey included farm scale, production specialization, structural dimensions of the houses and their ventilation systems, cooling and heating systems, and floor and pit systems related to manure collection. The survey showed 90∼99% of growing-finishing curtain installation rate was lower by 10∼20%. The sidewall curtain system, although popular, is not well insulated which leads to excessive heating costs in winter. Regarding flooring and manure collection system of the house, there was quite a lot variability among provinces, with 30∼80% of the houses installing scraper systems with concrete-slat floors in comparison with 30∼60% using a slurry system. Gangwon-do and Choongbook Chungwoo-goon are the predominant regions that installed a scraper system. A general trend toward enlargement and enclosure of pig houses for all growth phases was gaining popularity in most regions in recent years. A steady shift to three site production from a lumped system was also observed to prevent a disease transfer. The structural design of a standard pig house with its environmental control systems including ventilation and heating/cooling system was suggested for further validation study. In-depth analysis of the survey data is presented in the Results and Discussing section.