• 대한화학회지
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• 제29권4호
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• pp.365-371
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• 1985

이온쌍크로마토그래피에 의한 유기 및 무기음이온을 분리하는데 반대이온으로서 양이온 염료인 메틸렌 부루$(MTB^+)$를 사용하여 흡수가 되지 않는 음이온 시료를 간접적으로 분광광도 검출기로서 가시영역인 665nm에서 검출할 수 있었으며 혼합시료의 분리를 시도한 결과 좋은 분리도와 높은 감도를 보여주었다. 또한 여러 실험조건에서 분리인자를 측정하여 머무름 기구를 조사하였다. 본 연구에서 머무름 기구는 $MTB^+$가 고정상에 일차층(primary layer)을 형성하고 반면 음이온 시료 또는 이동상에 존재하는 다른 음이온들이 경쟁적으로 이차층(secondary layer)을 형성하는 ion-interaction model임을 확인하였다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2005년도 추계 학술대회논문집
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• pp.293-298
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• 2005

We calculate the coordinates of an axisymmetric nozzle with a central body. This nozzle ensures a transonic flow with a plane sound surface, which is orthogonal to the symmetry axis and has a wall kink at the sonic point, The Chaplygin transformation in the subsonic part of the flow leads the Dirichlet problem for a system of nonlinear equations. The definition domain of the solution in the velocity-hodograph plane is taken as a rectangle. This enables one to obtain the nozzle with a monotonic distribution of velocity along its subsonic part. In the nonlinear differential equation, the linear Chaplygin operator for plane flows is separated, which allows the iterative calculation of the solution. The supersonic part of the nozzle is calculated under the assumption that the flow at the nozzle exit is uniform and parallel to the symmetry axis; i.e., the supersonic jet outflows to the submerged space with the same pressure. The calculation is performed by the characteristic method. The exact solution of Tricomi equation for near-sonic flows with the straight sonic line is used to 'move away' the sound plane. The velocity distribution alone the supersonic part of the nozzle is also monotonic, which ensures the absence of the boundary-layer separation and, therefore, the adequacy of the ideal-gas model. calculations show that the flow in the supersonic part of the nozzle is continuous (compression shocks are absent)

• 한국잠사곤충학회지
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• 제39권1호
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• pp.22-29
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• 1997

Ultraviolet weavelength (UV) of 366 nm produced clearer fluorescent dolor than that of 254 nm for the inspection of silkworm cocoons. Fluorescent color of silkworm cocoons varied in color, appears no relationship with the natural color under the normal light. Uniformity of fluorescent color was improved by selection of blue or yellow line from wild types. Blue and yellow, located at the opposite poles on the color solid and L*a*b* color system, confirmed as pure standard of fluorescent color in the silkworm races for commercial white cocoons. the cocoons with blue fluorescence occupied as high as 1.7 to 8.6 times than those with yellow in the Japanese silkworm races. Fluorescence of silkworm cocoon was not affected by forced flow dry at 70$^{\circ}C$ for 6 hrs. While the Japanese races revealed no sexual difference in fluorescent color, sex-dependence of the color was common in the Chinese races for commercial white cocoon. The fluorescence of cocoon shell of Chinese races showed clear separation of blue of median color. Silkworm strain of Dc20 and Fc24 were sexualy segregated 98.8${\pm}$1.20%, 99.0${\pm}$1.00% by cocoon fluorescence, as that of 99.3${\pm}$0.44% by typical larval marking of sex-limited inheritance. Specific expression of cocoon fluorescence, applicable to breeding of simple discrimination of sex for Chinese races, inspected thoroughly on the surface and inner layer of cocoon shell.

• International Journal of Aeronautical and Space Sciences
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• 제4권2호
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• pp.17-25
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• 2003

Simple methods are developed to predict temperatures of a satellite box during launch stage. The box is mounted on outer surface of satellite and directly exposed to space thermal environment for the time period from fairing jettison to separation. These simple methods are to solve a 1st order ordinary differential equation (ODE) which is simplified from the governing equation after applying several assumptions. The existence of analytical solution for the 1st order ODE is determined depending on treatment of time-dependent molecular heating term. Even for the case that the analytical solution is not available due to the time dependent term, the 1st order ODE can be solved by relatively simple numerical techniques. The temperature difference between two different approaches (analytical and numerical solutions) is relatively small (Jess than $1^{\circ}C$ along the time line) when they are applied to STSAT-I launch scenario. The present methods can be generally used as tools to quickly check whether a satellite box is safe against space environment during the launch stage for the case that the detailed thermal analysis is not available.

• 대한한의학원전학회지
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• 제33권4호
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• pp.131-145
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• 2020

Objectives : This paper discusses Normal Birth in the Korean Medical context with a focus on bodily phenomena, with an aim to shed new light on what happens to mothers and the fetuses at the time of birth. Methods : Based on contents in the medical classics, changes that happen to the mother's body and their mechanisms were examined, followed by changes that happen in the fetus. The developments that happen to the fetus in the final month of pregnancy were studied in relation to aforementioned findings on the mother. Results : Signs of birth presented in the mother's body are manifestations of bodily changes that happen in a network with certain channels/meridians and viscera/bowels surrounding the uterus. The fetus prepares for birth as well, moving downwards into the mother's pelvis and his/her shen(神) getting prepared for separation from the mother's body. Conclusions : The birth process is not a race towards a finish line that ends with the birth of the fetus. It is rather a time wherein necessary changes in both the mother and the fetus takes place for a smooth and healthy birth.

• Animal Systematics, Evolution and Diversity
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• 제3권1호
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• pp.41-50
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• 1987

한국에 서식하는 A. chinensis의 골학적 특정을 조사하기 위하여 본 종이 속하 는 황어아과 어류와 가장 가까운 강준치아과 어류 수종의 골격들과 비교검토한 결과 등지느러미와 뒷지느러미의 기조수가 같고, symphyseal knob가 없으며dermosphenotic과 안상골이 접촉되어 있지 않고, 수염이 없는 점 등은 황어아과의 다른 어류들과 일치하였고, 복부 용골상 융기연과 전이골의 trigemino- facial nerve foramen이 2개인 점은 강준치아과 어류의 특정과 일치하였다. 그퍼나 상사골의 형태.4개의 안하골, 하미축골이 5-6개. 양안간격의 비가 57-60%, ex-trascapular가 없고, 선측이 불온전하고, 봄비 극히 왜소한 점 등은 오직 A. chi-nensis만이 특이하게 소유하고 있는 점으로 보아 본 종은 지금까지 보고되지 않은 새로운 아과에 해당되는 어류 분류군이 될 가능성도 있다. 그러나 이 점은 앞으로 보다 자세한 전기영동 분석과 수리분류학적 그리고 기타 형태학적 연구로 면밀히 검토되어야 할 것으로 믿는다.

• 수면정신생리
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• 제1권1호
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• pp.3-8
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• 1994

With the recent development of sleep medicine, insomnia has been perceived as a disease from a simple symptom. As there are various causes in a disease, proper treatment according to each cause is necessary for a more effective treatment In general, insomnia is classified into five categrories of physical, physiological, psychological, psychiatric and pharmacological aspects. However, such categorizations are often insufficient in treating insomnia. Furthermore understanding of the developmental mechanisms of insomnia is required. The function of sleep is developed and maintained through the balance of the reciprocal forces of sleep and arousal. These forces are contantly regulated by what is called a circadian rhythm. Sleep is induced by this rhythm which is affected by factors such as awakening time in the morning, amount of intellectual function, amount and time length of physical exercise and sunlight Insomnia could develop when this rhythm is delayed and leads to a "forbidden zone" which is a very difficult period for inducing sleep about two to four hours before the routine bedtime. Whereas sleep gradually develops in line with the circardian rhythm, arousal can occur very abruptly by any cause triggered by emotional discomfort or anxiety. Such characteristic and emotional factors as perfectionism, separation anxiety, secondary gain, insecurity, and negative cognition may provoke the inner anxiety and fear for insomnia, which can lead acute insomnia to a chronic one. As chronic insomnia is developed by multiple causes and factors, integrated approaches through analysis of above mentioned factors will be more effective in the treatment of insomnia than a simple administration of hypnotics.

• 대한기계학회논문집B
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• 제25권1호
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• pp.87-95
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• 2001

A numerical study was made of heat transfer in locally-forced turbulent separated and reattaching flow over a backward-facing step. The local forcing was given to the flow by means of sinusoidally oscillating jet from a separation line. A Rhee and Sung version of the unsteady $\kappa$-$\varepsilon$-f(sub)u model and the diffusivity tensor heat transfer model were employed. The Reynolds number was fixed at Re(sub)H=33,000 and the forcing frequency was varied in the range 0$\leq$fH/U(sub)$\infty$$\leq$2. The condition of constant heat flux was imposed at the bottom wall. The predicted results were compared and validated with the experimental data of Chun and Sung and Vogel and Eaton. The enhancement of heat transfer in turbulent separated and reattaching flow by local forcing was evaluated and analyzed.

• 복식
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• 제50권2호
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• pp.111-123
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• 2000

This study compares architecture with dress, investigates the image of transparency expressed in modern dress, and reveals its modern meaning. That is the purpose for this study. The study results are as follows. First, purity was expressed with simple, white color which has not any exaggeration or decoration, and transparent veils of wedding dress express clean and pure image which represents the original meaning of wedding dress. Second, eroticism conveys being erotic by exposing human body through transmission of light over transparent materials. Eroticism expressed by wearing thin and transparent dress with body-conscious line almost like being nude or emphasizing the sexually curious area in human body. The biggest difference in this study is that eroticism is delivered in dress, but not in architecture. Third, playfulness shows synchronism which recognizes human body with transmission of light over ,linear, transparent materials or recognizes inside dress. Playfulness expressed with location switch between inside and outside, exaggeration, distortion , and emphasis. Forth , openness makes dress atmosphere soft by putting transparent materials over opaque materials, expressed separation from restriction by wearing transparent dress over a naked human body, and expressed open ad free image by expressing human emancipation and freedom. Transparent dress expressed modern human being's sensitivity desire for living with light and joyful mood departing from heavy through, and also open and free image which pursues for freedom of human boedy departing from the restriction of human body.

• 한국정밀공학회지
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• 제3권4호
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• pp.53-63
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• 1986

In this study, the stress distribution of rectangular bar under torsion, when warping of both ends is free or constrained, is investigated. Method of separation of variable and Fourier Series are used for the theoretical analysis, and 3dimensional photoelastic stress-freezing method for experimental analysis. The main results are as follows; 1) In the case of warping-constrained rectangular bar, the normal stresses are negligible because they are less then 0.5% of the shear stresses. The maximum normal stress is placed on the point of y=0.61 b when b/a=1 and it gradually moves to the corner y=b when the value of b/a is increased. 2) According to increase of the value of b/a, on the crossection, the maximum shear stress is placed on the middle point of the long side (x=${\pm}a$, y=0) when warping of both ends is free but the middle of the short side (x=0, y=${\pm} b$) when warping is constrained. The stress distribution is straight line when warping is constrained, namely, the stress distribution is proportional to the distance from the axis of centroid, but parabolic when warping is free. 3) The values of the combined stress of warping-constrained bar, if the influence of the loaded point is neglected, are generally smaller than those of warping-free.