• 한국공작기계학회논문집
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• 제12권2호
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• pp.37-43
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• 2003

This study makes to flow analysis of computational fluid dynamics(CFD) according to the basic theory of turbulent flow regarding high-pressure injection nozzle. It also makes structural analysis to find out the structural validity of the optimum shape of high-pressure injection nozzle. It divides to two areas such as plunger areas and high-pressure injection nozzle area including plunger.

• Journal of Biosystems Engineering
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• 제18권4호
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• pp.390-401
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• 1993

This study was conducted to analyze the optimum capacity of Rice Processing Complex (RPC) and to select the optimum location of RPC based on the analysis of rice production and its commercializing rate for each county of major area of paddy field nationally. The study results showed that 500 of RPC having a drying capacity of 3,000 tons of rice would be needed nationally based on the selection analysis.

• 한국조경학회지
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• 제30권6호
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• pp.66-78
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• 2003

The purpose of this study was to minimize the forest disturbance around an entry road of a power transmission tower construction site between Taean and Sinsesan, Chungnam. The main study field was classified into existing materials and a GIS, remote sensing analysis, and a field examination. This information was used to identify the most suitable entry road using a degree of green naturality map, eco-naturality map, actual vegetation map, and a forest state map as the existing materials. Also, the study used an normalized difference vegetation index, altitude and slope map in order to make the evaluation materials which used an remote sensing image, and GIS. This data was used to choose an optimum area, and diagnosed the current condition of the vegetation with a field survey of the area. It analyzed vegetation structure, species diversity, the age of trees in a field examination. Subsequently, we proposed four area types based on the analysis results--preservation area, transplantation area, restoration area and development area. As a result, the preservation area was categorized into 8 grades, according to the degree of green naturality, large area of breast diameter at Pinus densiflora community, competition area of Pinus densiflora and Quercus spp. and Quercus spp. community of over 20 years old. A transplantation area established 46 optimum areas according to the GIS analysis and vegetation investigation results. Vegetation restoration plan for disturbance area should be made based on ecological value of existing vegetation to worthwhile area as Quercus spp. mixing forest proposed. The development area selected a ecological worthless place as an artificial forest where Pinus densiflora and Pinus thunbergii growth is poor. This research results suggest that restoration of vegetation will be possible in the real world. Also, ecological restoration guidelines will be made through building and analyzing data base and routine monitoring of transplantation and restoration area.

• 한국농공학회지
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• 제38권2호
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• pp.108-122
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• 1996

This study was to introduced estimation model for optimum probabilistic rainfall intensity on hydrological area. Originally, probabilistic rainfall intensity formula have been characterized different coefficient of formula and model following watersheds. But recently in korea rainfall intensity formula does not use unionize applyment standard between administration and district. And mingle use planning formula with not assumption model. Following the number of year hydrological duration adjust areal index. But, with adjusting formula applyment was without systematic conduct. This study perceive the point as following : 1) Use method of excess probability of Iwai to calculate survey rainfall intensity value. 2) And, use method of least squares to calculate areal coefficient for a unit of 157 rain gauge station. And, use areal coefficient was introduced new probabilistic rainfall intensity formula for each rain gauge station. 3) And, use new probabilistic rainfall intensity formula to adjust a unit of fourteen duration-a unit of fifteen year probabilistic rainfall intensity. 4) The above survey value compared with adjustment value. And use three theory of error(absolute mean error, squares mean error, relative error ratio) to choice optimum probabilistic rainfall intensity formula for a unit of 157 rain gauge station.

• 대한공업교육학회지
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• 제39권2호
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• pp.1-18
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• 2014

본 연구에서는 중등단계 직업교육에서 활용되고 있는 기존 발명 지식재산 관련 교과서를 대상으로 '발명 지식재산 핵심 학습 요소'의 반영 비율에 대한 편성 실태를 분석하고, 앞으로 중등단계 직업교육에서 요구되는 적정한 발명 지식재산 교육내용별 편성 비율을 제안하고자 하였다. 이를 위해서 현재 특성화고 및 마이스터고에서 사용되고 있는 발명 지식재산 교과서의 교육내용에 '어떤 종류의 발명 지식재산 핵심 학습 요소가, 얼마나 있는지와, 향후 어떤 학습 요소를 얼마나 편성하는 것이 바람직한가'를 연구 문제로 설정하였다. 이를 해결하기 위해서 내용분석 방법을 활용하여 발명 지식재산 교육내용의 반영 실태를 분석하고, 델파이 조사로 앞으로 요구되는 발명 지식재산 교육내용별 반영 비율을 제시하였다. 본 연구를 통해서 얻어진 결과를 제시하면 다음과 같다. 첫째, 중등단계 직업교육에서 활용되고 있는 기존 발명특허 인정도서에 포함된 발명 지식재산 핵심 학습 요소를 분석한 결과 모든 핵심 학습 요소가 교과서에 분포하고 있었으나 일부 교과서에서는 D(문제 해결과 활동)영역이 집중되어 있는 경향이 있었다. 둘째, 중등단계 직업교육에서 활용되고 있는 발명특허 인정도서에 제시되어 있는 발명 지식재산 교육내용의 영역별 반영 비율을 분석한 결과 대부분의 교과서가 창출영역에 치중되어 있는 경향이 있었으며, 일부 교과서에서는 보호영역과 활용영역을 다루고 있었다. 그러나 대체적으로 활용영역에 대한 반영 비율이 미흡한 실정이었다. 성취유형별로는 모든 교과서에서 지식영역이 주를 이루고 있었다. 또한 발명특허기초, 발명과 문제해결, 발명과 디자인 교과서에서만 기능영역을 일부 다루고 있었으며, 태도영역은 대부분의 교과서에서 없거나 미흡하게 다루고 있었다. 셋째, 전문가 델파이 조사를 통해 얻어진 중등단계 직업교육에서 요구 되는 발명 지식재산 교육 핵심 학습 요소 영역 중에서 D(문제 해결과 활동) 17.7%, E(발명 융합 지식) 2.9%, K(특허출원) 6.9%, L(특허정보 조사) 9.6%를 줄여야 하는 것으로 나타났다. 발명 지식재산 교육내용 중에서 발명 소양영역 3.1%, 지식재산 창출영역 4.5%, 지식재산 보호영역 10.6%를 줄여야 하고, 지식재산 활용영역은 17.7%를 늘려야 하는 것으로 나타났다. 또한 성취유형의 적정 반영 비율은 지식영역은 52%를 줄여야 하고, 기능영역 32.3%, 태도영역 19.6%를 늘려야 하는 것으로 나타났다.

• 한국식품조리과학회지
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• 제12권3호
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• pp.305-311
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• 1996

This study was to seek menu model in usual dishes to guarantee the optimum salt intake considering the optimum gustation of salt surveyed on Korean adults. First, a pilot test was practiced using rice gruel to determine the criteria and a meaningful interval of salt concentration. Based on the criteria and interval so determined, a test was performed to seek the optimum gustation of salt concentration in usual diets. Subjectgroup for the above tests was university students living in Kyung-Book area. The results were as follows: 1. Mode value of the optimum gustation of salt was 0.5% and the received threshold difference of salt was 0.2% in the pilot test. 2. Mode values of the optimum gustation of salt in a la carte, soups and stews were lower than those of other side dishes. 3. But the portion size of a la carte, soups and stews is much larger than that of other side dishes, so that a la carte, soups and stews are sources of relatively larger amount of salt than other side dishes. 4. Considering the recommended optimum salt intake, it is desirable to reduce the amount of stock in soups and stews and to select fried food or salad more frequently.

• Journal of Forest and Environmental Science
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• 제35권3호
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• pp.173-180
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• 2019

This study determined the economic impact of environment-friendly cultivation and the optimal cultivation area of Omija (Korean for Schisandra chinensis Baillon) for full-time farmers by analyzing the management performance of existing Omija cultivators. The study divided the target income into urban household income and Omija farm income, and estimate the optimal cultivation area by substituting the target profit from the cost-volume-profit analysis model. The optimum cultivation area was 1.4 ha for general cultivation, 1.08 ha for organic cultivation, and 1.18 ha for pesticide-free farming cultivation considering the average urban household income as the target, and 0.81 ha for general cultivation, 0.63 ha for organic cultivation, and 0.69 ha for pesticide-free farming, considering the average 2012 farm household income as the target. Therefore, the study reached conclusion that it is necessary to secure the price of Omija farm and stable support for income increase. Therefore, the support plan for income stabilization of Omija farm should be considered. Especially, the central government should provide various policies and financial support to help the optimal cultivation area of Omija Farm.

• 대한토목학회논문집
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• 제4권4호
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• pp.127-135
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• 1984

본 연구는 실제 하중을 받는 강재 아치구조의 최적형상을 다루었다. 목적함수로는 아치의 중량을 취했으며, 제약조건으로는 단면력, 체적, 아치리브의 길이, 아치부채 단연적의 조합으로 구성된 웅력제약초건을 고려하였다. 형상최적화문제는 아치부재의 단면척이 설계변수의 항으로 형성되었으며, 첫단계로 구조해석의 정밀도가 최적 설계의 목적함수값에 미치는 영향을 분석하였다. 형상최적화 알고리즘은 Two-space System 으로 형성되었고, Space 1 에서는 Modified Newton-Raphson Method에 의한 단면최적화, Space 2 에서는 Powell Method 에 의한 형상최적화를 시도하여 형상최적화 알고리즘을 도출하였다. 본 연구에서 도출된 최적화 알고리즘을 이용하여 아치의 단면최적화와 최적 아치형상에 관한 연구가 수행되었다. 이 알고리즘에 의해 실제 조건하에서 아치의 최적 Span-Rise 비를 구할 수 있다.

• Structural Engineering and Mechanics
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• 제15권1호
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• pp.39-52
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• 2003

A computer program has been developed for the optimum design of prestressed concrete beams under flexure. Optimum values of prestressing force, tendon configuration, and cross-sectional dimensions are determined subject to constraints on the design variables and stresses. 28 constraints have been used including flexural stresses, cover requirement, the aspect ratios for top and bottom flanges and web part of a beam and ultimate moment. The objective function contains cost of concrete, prestressing force and formwork. Using this function, it is possible to obtain minimum cost design, minimum weight or cross-sectional area of concrete design and minimum prestressing force design. Besides the idealized I-shaped cross-section, which is widely used in literature, a general I-shaped cross-section with eight geometrical design variables are used here. Four examples, one of which is available in the literature and the others are modified form of it, have been solved for minimum cost and minimum cross-sectional area designs and the results are compared. The computer program, which employs modified grid search optimization method, can assist a designer in producing efficient designs rapidly and easily. Considerable savings in computational work are thus made possible.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.250-250
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• 2017

Studies were conducted to select the optimum sowing date and planting density of sesame in the middle area of Korea. To select the optimum sowing date, sesame seeds sowed from 20 April to 7 July with 15-day intervals. To select the optimum planting density, sesame seeds investigated under four different planting distances ($30{\times}10,\;30{\times}15,\;30{\times}20$, and $30{\times}25cm$)respectively in the experimental field. As seeding date was delayed, days to emergence were shortened flowering and maturing date were delayed. Delayed sowing date resulted in decreased length, capsule setting stem length and number of capsules, and branchs per plant. Number of Capsules was high sowing date on 5 May in the range of 90~95ea/plant in sesame. Also yield of sesame seeds was most high on 5 May in the range of 142kg/10a by sowing date. Sowing date up to 5 May showed no effect on grain yield, but from 5 June to 5 July decreased 27%, 68% and 86%, respectively. For all planting distances, weight of 1,000 grain was not significantly different. However, number of branches and capsules tended to increase. Number of Capsules was high planting distance of $30{\times}20cm$ and $30{\times}25cm$ in the range of 146.7~165.7ea/plant in the Geonbaekkae. Areumkkae also showed the same tendency on planting distance of $30{\times}20cm$ and $30{\times}25cm$ in the range of 122.0~147.5ea/plant, respectively. Yield of Geonbaekkae and Areumkkae seeds was most high 116kg/10a, 117kg/10a, respectively on planting distance $30{\times}20cm$. Decreased in the planting distance of sesame has increased the incidence of disease and lodging. Based on the results, we suggest a planting distance of $30{\times}20cm$ maximal growth and yield of sesame in the middle area of Korea. Considering growth characteristics, sesame yield ability, the optimum sowing date was 5 May and optimum planting pattern was founded to be two rows planting in one ridge and planting densities was $30{\times}20cm$.