• 대한기계학회논문집
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• 제13권2호
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• pp.257-264
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• 1989

본 연구에서는 높은 열확산의 재료까지도 수용할 수 있도록 시편의 전면 전체를 가열하는 기존의 방법으로부터, 가열하는 시편 전면의 면적을 그 중심으로 부터 임의로 조절하여 축 및 반경방향의 열흐름을 강화시켜, 반경방향의 온도를 측정한 후 이를 이용하여 열확산계수를 구할 수 있는 방정식을 제시하였다. 방정식에서는 시편의 전.후면은 물론 열원의 방사시간도 함께 다루었다.

• 한국조경학회지
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• 제13권2호
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• pp.37-70
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• 1985

The purpose of this study is to present objective basic data for environmental design by the quantitative analysis of visual quality emboded in physical environment. For this, as for the front garden of high schools, the spatial image was measured by the S.D. Scale Method, Factor Analysis was proceeded by the principal component analysis and the visual preference was investigated by the Paired Comparision Method. The scale values of plain and unpleasant road surface and external appearance of buildings, which are related to emotions of simpleness fell from straightness and stability, were found to be high. But, except for the road surface of Kyunggi High School, scale values of variables explaining the variation of the quality of materials, level of floor and rythm were generally low. For all green spaces, scale values of variables explaining the degree of pleasantness was found to be generally high. And, those explaining tidiness and characteristics of green spaces were not in the same tendency. But, the green spaces of Youngdong High school can be considered to the space with plenty of visual absorption uniqueness were high. As for the correlation between variables, variables for green spaces(12 and 26) and those for overall view of front garden( 1 and 4) revealed high positive correlation. Also, "order - disorder" and "convenient- incovenient" included in road surface variable can be regarded to have the same meaning since the correlation coefficient between them is very high, 0.7045. Image variables including road surface, external appearance of buildings, green spaces and overall view of front garden showed 91.21~61.08% of total variance. Thus, the remains can be considered to be the error valiance or specific variance. In Fctor I, II and III, main components explaining the road surface image of front gardens are order, hardness, texture, color, gradient and rythm. As for the external appearance of b wilding, variables of color, hardness, stability, peculiality and shape revealed high values of factor load. For all variables, communality was drastically high and ellen values and common variance were found to be very high in Factor I. As for the front gardens, variables explaining volume and peculiarity were found to be the main components of Factor I. In Factor II and III, variables of factor load were tidiness, pleasantness.

• 대한기계학회논문집A
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• 제28권6호
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• pp.701-708
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• 2004

This paper discusses applicability of the enhanced reference stress method to estimate J-integral along the semi-elliptical surface crack front. It is found that angular variations of normalized J­integral are strongly dependent on the geometry, loading mode and loading magnitude. As application of the reference stress approach to semi-elliptical surface cracks implies proportional increases in the normalized J-integral, the present results pose a question in applicability of the reference stress approach. However, investigation of the error in the estimated J-integral in the present work suggests that the enhanced reference stress approach, recently proposed by authors, provides an effective engineering tool fur estimating crack driving force along the semi-elliptical surface crack front.

• 한국의류학회지
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• 제17권4호
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• pp.608-621
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• 1993

The Purposes of this study were 1)to find the body surface total line and segment line significantly(${\alpha}$=0.05) changed by the leg movement including all movement direction of hip joint, knee joint and ankle joint for the more functional clothing. 2)to classify them into 3 types-expansion type, contraction type, expansion & contraction type, and 3)to identify the characteristics of the body surface length changes. 10 Crosswise and 5 lengthwise body surface total lines and 48 crosswise & 39 lengthwise body surface segment lines of 26 female college students aged from 18 to 24 years were measured directly on the body surface and were analyzed by ANOVA & Multiple Comparison Test (Tukey). The results were as following : Body surface total lines significantly changed were all the body surface total lines except abdoman girth, 1/2thigh girth of lower leg and ankle girth, and these were classified into 3 types : Center front leg line belonged to expansion & contraction type, whereas lateral leg line, legscye girth, and total crotch length belonged to contraction type. The rest belonged to expansion type. Knee girth showed maximum expansion, whereas center front leg line showed maximum contraction. Body surface total lines have shown large expansion crosswise whereas lengthwise they have mainly shown contraction. At least more than one component segment line of each body surface total lines except abdoman girth and ankle girth have shown significant change. Top segment of inner leg line showed maximum expansion. whereas just below top segment of center front leg line showed maximum contraction. Crosswise all the body surface segment lines have shown expansion except inner back segments of thigh girth and 1/2thigh girth of upper leg which have shown contraction. Lengthwise they have shown both expansion and contraction according to the location of front or back, and below or upper 1/2thigh girth line except the component segment lines of lateral leg line, which has shown contraction only.(cf. figure 2. figure 3. and table 2-2).

• 한국안광학회지
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• 제9권2호
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• pp.417-421
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• 2004

안경렌즈 면 위에 반사되는 상을 관찰하연 한 물체에 대해 두 개의 상이 나타나 있다. 이것은 렌즈 전면에서 반사되는 상과 렌즈 후면에서 반사되는 상이다. 이 상들은 렌즈 전, 후면의 굴절력에 의해 렌즈 면에서 반사되는 상이며, 렌즈 전체의 굴절력은 렌즈 전, 후면의 굴절력을 이용하면 얻을 수가 있다. 그러므로 렌즈 면 위에서 나타나는 상 크기 측정은 렌즈의 굴절력을 측정하는 기기의 도움 없이 렌즈의 굴절력을 측정하는 방법이 될 수 있다. 렌즈 면 위에서 측정된 두 개 반사상의 비와 굴절력을 측정하여 계산한 값과 비교하였다.

• 한국전기전자재료학회논문지
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• 제35권6호
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• pp.616-621
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• 2022

Numerical simulation is a good way to predict the conversion efficiency of solar cells without a direct experimentation and to achieve low cost and high efficiency through optimizing each step of solar cell fabrication. TOPCon industrial solar cells fabricated with n-type silicon wafers on a larger area have achieved a higher efficiency than p-type TOPCon solar cells. Electrical and optical losses of the front surface are the main factors limiting the efficiency of the solar cell. In this work, an optimization of boron-doped emitter surface and front electrodes through numerical simulation using "Griddler" is reported. Through the analysis of the results of simulation, it was confirmed that the emitter sheet resistance of 150 Ω/sq along the front electrodes having a finger width of 20 ㎛, and the number of finger lines ~130 for silicon wafer of M6 size is an optimized technology for the front emitter surface of the n-type TOPCon solar cells that can be developed.

• Water Engineering Research
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• 제3권1호
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• pp.9-22
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• 2002

In general, two dimensionless numbers are used in predicting the front propagation rate of density currents: the densimetric Froude number and the dimensionless front velocity. The former expresses the front speed in terms of the characteristic length and reduced gravitational acceleration. Previous papers report that the range of this dimensionless number is wide. The other is the dimensionless front velocity, which is a function of the buoyancy flux per unit width. This paper presents the state of the art review of the dimensionless numbers for the front propagation rate of density currents. Values of the densimetric Froude number are found to be consistent when the proper characteristic length is used for normalization. Then, the densimetric Froude number and the dimensionless front velocity are compared by using the experimental data of density currents over a horizontal surface.

• 한국해양학회지
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• 제25권2호
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• pp.84-95
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• 1990

CTD, 해류계, 인공위성 영상사진을 이용하여 황해 중부의 조석전선 주변역을 조사 한 결과 몇 가지 물리적 특성을 알 수 있었다. 전선은 태안반도 끝 부분을 중심으로 하여 4월 중에 태양열에 의한 해표면 가열과 함께 나타나기 시작하여 8월에 가장 뚜렷 하며 11월에는 표층냉각과 함께 소멸한다. 전선의 북측에서는 전선을 가로지르는 조류 에 의하여 수온 염분의 조석주기 변화가 나타남으로써 전선구조를 보여준다. 경기만에 서 나타나는 전선은 통최상의 조석전선과 달리 한강에서 유출된 담수와 외양수의 만남 에 의하여 형성된다. 표층냉수의 중심에서는 조석혼합역이 연안으로부터 약 50 km 외 양하지 분포한다. 전선의 남측에서도 전선의 구조는 비슷하나 전반적으로 혼합 정도가 약하게 나타난다. 이 연안 혼합역의 연안쪽에서는 금강유출된 담수에 의하여 염분전선 이 좁은 범위에서 흥성된다. 이 염분전선 부근의 일부에서는 용승과 같은 현상이 관측 되었다.

• Korean Journal of Acupuncture
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• 제17권1호
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• pp.157-171
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• 2000

Front Points are told to be deeply related with viscera and bowels in oriental medicine. Since the Front Points are treated as response zone, it can be used for the diagnosis and treatment of disease in viscera and bowels. The location of Front Points are very similar to the several response zones in western medicine. Diagnostic aspect of Front Points to several response zones were discussed in here based on many thesis and reported laboratorial experiments. Front Points are located in the same latitude of viscera and bowels. So, diagnosis result in Front Points represent condition of each organs. Palpitation of the Front Points can make diagnosis of body surface and the organ beneath the body surface. Such use of Front Points for diagnosis can used as the treatment points also. Only three Front Points (LU-1, LI-14, GB-24) in lung, liver and gall bladder meridian are located on its meridian. The Front Points of Stomach (CV-12) cross its meridian or closely located to it. Unlike to those four Front Points that are matched to its meridian, other eight Front Points do not located or cross its meridian at all. It seems that the location of Front Points are decided by the location of organs and the conditions at a certain organ do not delivered by the meridians but delivered by main collaterals, tertiary collaterals and superficial collaterals instead. Among visceral response zones, Five Front Points (CV-3, CV-4, CV-12, LI-14, GB-25) are exactly matched to Head's response zone and other Front Points are closely matched to the Head's response zone. There are five Front Points (CV-12, CV-14, CV-17, LI-14, GB-24) that are matched with the location of pressing palpitation point and other Front Points are closely located to the pressing palpitation point. So far, it was clear that the Front Points do have important role as response points. Symptoms expressed to the Front Points were delivered conditions or symptoms occur in corresponding organ and the anatomical location of Front Points were also found near the corresponding organ. Diagnostic and therapeutic application of Front Points for Organ theory and in the Interpromotion-restraint of the five elements in oriental medicine can be made in future to increase its potential.

• 한국자동차공학회논문집
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• 제13권4호
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• pp.81-89
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• 2005

The response surface method is the statistical method which can be applied to the non-sensitivity based optimization. The response surface which is constructed by the least square method contains only the polynomial terms so that the global maximum and minimum points are easily obtained. In this paper, this response surface method is utilized to optimize the crashworthiness of auto-body members. As the first step, the thickness of a simple circular tube is optimized to confirm the application of the response surface method to the crashworthiness. Optimization of the thickness on the front side member is, then, performed with the constructed response surface of the absorbed energy and deformation. Optimization results demonstrate that the absorbed energy and the deformation pattern of the front side member is improved in the viewpoint of enhancement of the crashworthiness.