• 대한기계학회논문집
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• 제10권1호
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• pp.78-85
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• 1986

본 연구에서는 결함재의 결함선단에 발생 전파하는 피로거동을 검토하기 위해서 미소원공과 미소슬릿을 가공하고, 이것들의 피로한도를 기준으로 해서 이들 결함의 형상이 피로크랙 전파특성에 미치는 영향을 상세히 고찰하고자 한다.

• 대한기계학회논문집B
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• 제25권6호
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• pp.758-765
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• 2001

Purpose of the present is to investigate the food configuration at a tunnel entrance for reducing the micro pressure wave that is generated according to train speed. Two configurations were examined for tunnel of 0.5 km length. The experimental results show that a slit cover hood installed at the entrance of the tunnel reduces the maximum micro pressure wave by 41.2%, and a configuration with a slit cover hood installed at the entrance and a 45$^{\circ}$slanted portal at the exit of the tunnel suppresses it by 47.7%.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.619-624
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• 2000

The purpose of present study is to investigate for reducing micro pressure waves generated according to train speeds $(240km/h{\sim}380km/h)$ through tunnels with countermeasures as followings; the hood configuration in tunnel entrance. We developed hoods for tunnel of 0.5 km length in the condition of tunnel cross-section area of $107m^2$ on the slab track. According to the results the maximum micro-pressure wave is reduced by 41.2% for the slit hood installed at the entrance of the tunnel and reduced by 47.7% for the slit hood installed at the entrance of the tunnel and the $45^{\circ}$ slanted portal at the exit of the tunnel

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.335-340
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• 2001

There are many tunnels located apart short distance from each other in mountainous country like Korea. Serial tunnels are connected by snow shelter in many cases. This study presents some countermeasures against micro-pressure wave at the tunnel exit using snow shelter. Through 1/60 scale model laboratory test, we find that snow shelter with 3.6m slit and slit cover show the effect of reducing the micro pressure wave to about 50.6%.

• 한국터널지하공간학회 논문집
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• 제2권3호
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• pp.3-11
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• 2000

본 연구의 목적은 고속철도 터널 입구에 슬릿 커버 후드를 적용하여, 고속열차 터널 진입시 터널 출구 쪽에서 방사되는 미기압파를 저감시키는데 있다. 경부고속철도 $107m^2$의 단면적을 갖는 슬라브 궤도 0.5 km 터널에 대하여 슬릿 커버 후드라는 구조물 대책을 마련하였다. 개발시험 결과는 터널 입구에만 후드를 설치했을 경우 미기압파가 최대 41.2 %가 저감되었으며, 터널 입구에 후드를 설치하고 출구에 $45^{\circ}$ 경사갱구를 설치했을 경우는 47.7 %가 저감되었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.390-395
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• 2000

There are many tunnels located apart short distance from each other in mountainous country like Korea. Serial tunnels are connected by snow shelter in many cases. This study presents some countermeasures against micro pressure wave at tile tunnel exit using snow shelter. Through 1/60 scale model laboratory test. we find that snow shelter with 3.6m slit and slit cover show the effect of reducing the micro pressure wave to about 60.5%.

• 한국의류학회지
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• 제17권4호
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• pp.539-549
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• 1993

The purpose of this study was to find out the moving fitness and slit length of tight skirt in relation to its length & silhouette. Five kinds of length, micro mini, mini, natural line, medi and maxi, and two kinds of siihuette, slim & straight-a total of ten tight skirts-were investigated. Ten college students were chosen for this experiment. The moving fitness was tested by measuring the step length, step width and step angle in the case of walking on the flat and going up the stairway & bus stair. The slit length was tested by measuring the back slit length needed in the case of going up stairway & bus stair. Data were analyzed with use of SAS pakage. The statistics were based on average, standard diviation, two-way ANOVA, Pearson's correlation and multiple regression analysis. The main results were as follows. 1. There was significant difference in the moving fitness according to length & silhouette of tight skirt. The moving fitness of slim type was lower than that of straight type and the longer the skirt length was, the lower the moving fitness was. The significance appeared particularly in the case of going up the bus stair. 2. There was significant difference in the skirt length obove slit accorting to length & silhouette of tight skirt. The skirt length obove slit of slim type was shorter than that of straight type. The longer skirt length was, the longer it was from micro mini to natural line, that of medi skirt was shorter or a little longer than that of natural line skirt and there was little change from medi skirt to maxi skirt.

• Korea-Australia Rheology Journal
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• 제19권2호
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• pp.51-59
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• 2007

A polyelectrolyte chain confined in a slit nanochannel exhibits a structural transition from the one in free space. In this paper, the effect of the long-range electrostatic interactions between the xanthan polyelectrolyte and the slit wall on the confined xanthan conformation is investigated via the Brownian dynamics simulation. A neutral and two negatively charged surfaces of polydimethylsiloxane (PDMS) and glass are combined to make four kinds of slit channels with different charge characteristics: i) neutral-neutral, ii) glass-glass, iii) neutral-PDMS and iv) neutral-glass walls. Their walls are characterized by uniform surface charge densities determined from experimental data of zeta potential. Both the nonmonotonic chain size variation and the loss of long-range bond vector correlation, previously observed under confinement in the PDMS-PDMS slit, are also found in the neutral slit, demonstrating the nonelectrostatic origin of such crossover behaviors. As expected, the effect of wall charges is negligible at sufficiently high medium ionic strength of 100mM but it becomes significant in the opposite limit of 0.01mM. In the latter case, the high charge density of glass walls strengthens the effective confinement of a negatively charged polyelectrolyte and produces a xanthan structure comparable to that confined in a much narrower neutral slit. The obtained structural data suggest the possibility of controlling the structure of confined polyelectrolytes by the modification of surface charge characteristics of micro/nanofluidic devices in combination with the adjustment of the medium ionic strength.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.561-564
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• 2003

The machining technology for the removal of micro-burr has been demanded because electrode parts of electron gun have minute holes. In this study, Magnetic Assisted Polishing(MAP) is applied to remove the micro-burr instead of the contentional polishing process such as the etching and barrel. Optimal polishing conditions are selected from many experiments using the tool of the flat end slit type. On the basis of experimental results, the deburring machine for the Magnetic Assisted Polishing of electrode part is developed and its performance is evaluated.

• 한국광학회지
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• 제24권2호
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• pp.53-57
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• 2013

본 논문에서는 금속 슬릿 배열로 구성된 편광 선택 가능한 블레이즈드 회절 격자를 제안한다. 마이크로 스케일의 블레이즈드 회절 격자를 디자인 하고 이 구조에 추가적으로 나노스케일의 금속 슬릿 구조를 적용하여 편광 선택기능을 부여하였다. 이 소자에 대하여 사례 연구로 예를 디자인하여 FDTD(Finite Difference Time Domain method)방법을 이용한 전산모사를 통해 성능을 검증해 보았다. 임의의 디자인 사례에 대해 대략 77.61% 의 회절효율과 8.99의 편광선택비가 얻어졌으며 편광선택비를 높이기 위한 또 다른 디자인에서는 64.22%의 회절효율과 81.09의 편광선택비가 얻어졌다.