• 대한기계학회논문집
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• 제8권5호
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• pp.442-449
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• 1984

본 연구에서는 두 분류가 교우되어 배합이 이루어지는 유동역에서 3차원 방향 에 대하여 평균속도분포, 난류강도분포, 난류전단응력분포, 상관계수의 분포 및 난류 운동에너지와 운동량의 변화 등을 측정 분석하였다.

• 대한기계학회논문집B
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• 제25권6호
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• pp.799-803
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• 2001

Miniature heat pipe(MHP) with woven-wired wick was used to cool the CPU of a notebook PC. The pipe with circular cross-section was pressed and bent for packaging the MHP into a notebook PC with very limited compact packaging space. A cross-sectional area of the pipe is reduced about 30% as the MHP with 4mm diameter is pressed to 2mm thickness. In the present study a performance test has been performed in order to review varying of operating performance according to pressed thickness variation and heat dissipation capacity of MHP cooling module that is packaged on a notebook PC. New wick type was considered for overcoming low heat transfer limit when MHP is pressed to thin-plate. The limiting thickness or pressing is shown to be within the range of 2mm∼2.5mm through the performance test with varying the pressing thickness. When the wall thickness of 0.4mm is reduced to 0.25mm for minimizing conductive thermal resistance through the wall of heat pipe, heat transfer limit and thermal resistance of MHP were improved about 10%. In the meantime, it is shown that the thermal resistance and heat transfer limit for the MHP with central wick type are higher than those of MHP with existing wick types. The results of performance test for MHP cooling modules with woven-wired wick to cool a notebook PC shows the stability as cooling system since T(sub)j(Temperature of Processor Junction) satisfy a demand condition of 0∼100$\^{C}$ under 11.5W of CPU heat.

• 한국터널지하공간학회 논문집
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• 제17권4호
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• pp.415-428
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• 2015

국내의 장대터널 및 도심지내 터널시공과 시공계획이 증가함에 따라 터널굴착기술의 개발이 요구되고 있다. 국내의 터널 굴착방법으로 drilling & blasitng method가 주로 쓰이고 있는 실정이나 이 공법은 극심한 발파진동으로 현장주민의 민원과 인근 암반구조물에 피해를 입히는 단점이있다. 따라서 문제발생예측 지역에는 무발파 굴착공법인 TBM터널링을 사용하는 것이 효율적이다. 하지만 TBM 터널링은 drilling & blasitng method와 비교하였을 때 비경제적이므로 현장에서 꺼리는 실정이다. 이러한 한계를 극복하기 위하여 다양한 TBM 장비 및 시공기술이 요구된다. 또한 관련된 기술의 기준이 될 수 있는 시방서 및 설계기준의 지속적인 개정도 필요한 상황이다. 본 연구에서는 2015년 고시된 터널표준시방서내 TBM에 대한 개정 내용 및 관련 해설에 대한 내용을 다루고 있다.

• 컴퓨터교육학회논문지
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• 제14권3호
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• pp.1-12
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• 2011

'정보기기의 구성과 동작' 영역은 5차 교육과정에서 개정 교육과정에 이르기까지 지속적으로 정보교과의 교육과정에 포함되어 왔다. 그러나 이 영역에 대한 내용선정이나 교수방법 등과 같이 교육적 본질에 대한 논의는 전혀 이루어지지 않았다. 따라서 본 연구는 현대 교육과정의 관점에서 '정보기기의 구성과 동작' 영역의 탐구적 경향을 분석하였다. 4개의 교과서를 대상으로 분석한 결과, 1개의 교과서만이 탐구적 교과서로 나타났다. 연구 결과를 토대로 본 연구는 교과서의 제작에서는 내용의 중요성과 학습활동의 관점을 함께 고려할 것, 융복합의 시대에 기본이 되는 교과로서 단순 암기의 지식보다는 성찰을 제공하는 교과임을 고려해야 함을 제안하였다.

• 재활복지공학회논문지
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• 제9권4호
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• pp.319-329
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• 2015

본 논문에서는 다자유도 동적 하네스 시스템 개발을 위해 일상동작에서와 트레드밀 보행 시 하네스 체중 지지에 따른 하지 동작 패턴에 관한 연구를 수행하였다. 건강한 성인 남성 5명을 대상으로 일상생활 동작과 하네스 체중지지에 따른 좌, 우 대퇴직근, 외측광근, 전경골근, 외측 비복근과 족압을 측정하였다. 실험 결과, 일상생활 동작 수행 시 EMG는 각 구분 동작들에 따른 특이적인 근육 활성을 나타내었다. 슬관절의 굴곡과 신전을 요하는 앉기, 서기, 계단 오르기, 계단 내리기 동작에서의 외측광근의 활성이 두드러졌다. 족압 분포의 경우 일상생활 동작 중 중력방향으로 내려오는 계단 내려오기 동작에서 가장 큰 족압 분포 값을 보였다. 수동형 하네스 체중 지지율이 증가에 따라 근육 활성도와 족압 분포 값은 감소하는 경향을 보였다. 이러한 결과를 토대로 체중지지를 통한 보행 훈련이 체중지지율 변화에 따라 다양한 환자 군에 적용 시킬 수 있을 것이다 판단된다.

• Nuclear Engineering and Technology
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• 제41권1호
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• pp.135-142
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• 2009

In this investigation, we prepared a 1 and 3-parallel serpentine single PEMFC, which has an active area of $100\;cm^2$ and a flow channel cross section of $1{\times}1mm$. Distribution and transport of water in a non-operating PEMFC were observed by varying flow types and the flow rates (250, 400, and 850 cc/min). This investigation was performed at the neutron imaging facility at the CO1d Neutron RAdiography facility (CONRAD), HMI, Germany of which the collimation ratio and neutron fluence rate are 250, $1{\times}10^{6}n/s/cm^2$, respectively. The neutron image was continuously recorded by a scintillator and lens-CCD coupled detector system every 10 seconds. It has been observed that although the distilled water was supplied into the cathode channel only, the neutron image showed a water movement from the cathode to the anode channel. The water at the cathode channel was completely discharged as soon as the pressurized air was supplied. But the water at the anode channel was not easily removed by the pressurized air except for the 3-parallel serpentine type with 850cc/min of air flow rate. Moreover, the water at the MEA wasn't removed for any of the cases.

• 한국의류학회지
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• 제29권9_10호
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• pp.1349-1358
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• 2005

Generally apparel products were recognized as an incongruent product type which direct search was needed for. But nowadays apparel products were ranked as a second product type next to electronics in sale amount of internet shopping mall. Therefore more detailed study on which attributes of fashion products are more successful and suitable in internet shopping mall is necessary. This study was executed to analyze common attributes of successful apparel in internet shopping mall on the basis of real sale data, and then to help internet apparel marketer plan marketing strategies more efficiently. Common attributes of successful apparel products in internet shopping-mall in terms of product, price and promotion attributes were identified. 240 products which were loaded in bestseller section of internet shopping-mall for 8 weeks from November to December, 2004 were analyzed. The results are as follows. First, products ratio for women ($76.7\%$) were higher than for men($18.3\%$). And the amount of each apparel product types purchased by consumers were ranked in the order of leather/fur coat, woven coat, inner wear, jacket, T-shirts, pants, training wear, suit, knit wear etc. and basic style dominated in $74.2\%$. General brands ($69.2\%$) that had price competitiveness were preferred to famous designer brand, national brand and PB brand. Preferred level of price was ten thousand to fifty thousand won. For promotion skill, in order of just one product, product adding promotion product and package set were preferred. Regular price, less than $50\%$ off and more than $50\%$ off price showed no difference in preference. Product planning strategy for internet apparel marketer was followed on the basis of these results.

• 한국의류학회지
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• 제35권8호
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• pp.933-945
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• 2011

This research proposes a pattern design method for 24 pleated skirts in order to develop an automatic draft program for pleated skirts that will enhance fit and enable mass production. The research method and results are outlined as follow. 1. Three-dimensional body measurements were conducted on 30 randomly selected women in their 20s. By using 34 body measurement items and 6 types of calculations among the items, the items required in the designing of an original pleated skirt were extracted. They were then interpreted through correlation analysis, variance analysis, a t-test, linear regression analysis and multiple regression analysis. 2. An extra amount was added to the waist measurement and external capsule measurement according to the number of times the pleats coincided and the thickness of the fabric by the degree of polymerization of the horizontal cross section (the test of this research: 0.518mm). The extra amount of waist measurement was 3.6cm while the hip measurement was 4.3cm larger than the hip measurement combined with the external capsule measurement and the extra amount. 3. Based on the ${\pm}$standard deviation/2 as the average of the difference between the external capsule measurement and waist measurement, the subjects were classified into 3 somatotypes. Somatotype 1 presented an average total length of waist darts of 23.6cm while that of somatotype 2 was 26.2cm and that of somatotype 3 was 30.2cm. It has been confirmed that there is a significant difference among somatotypes in the total length of waist darts from the front center to the front side and the total length of waist darts from the side to the back center in terms of the average amount of waist darts for every 12 parts on the WL.

• The Plant Pathology Journal
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• 제22권2호
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• pp.155-160
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• 2006

A strain of Pepper mottle virus (PepMov) was isolated from chili pepper plants in Korea. In host range study, this virus, designated PepMoV-SNU1, shared most characteristics with PepMoV isolates reported previously. Thermal inactivation point ($45^{\circ}C\;to\;75^{\circ}C$) and dilution end point ($10^{-1}\;to\;10^{-4}$) of PepMoV-SNU1 showed differences depending on the propagation hosts. Cylindrical and pinwheel-shaped inclusions were always observed in pepper leaf tissues infected with the virus alone. Unexpectedly, a special structure of pinwheel shaped inclusion surrounded with unknown small spots was also observed in the leaf section when co-infected with a strain of pepper mild mottle virus. The partial sequence of coat protein gene and 3' untranslated region of PepMoV-SNU1 showed 98% identity with those of other PepMoV isolates. A primer pair derived from 3' end of the coat protein gene and poly A tail regions were designed. Optimal detection condition of PepMoV-SNU1 by RT-PCR was tested to determine appropriate annealing temperature and additional volumes of oligo-dT (18-mer), dNTP, and Taq polymerase. Under the optimized condition, an expected 500 Up PCR-product was detected in pepper leaves infected with PepMoV-SNU1 but not in healthy plants.

• 한국도로학회논문집
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• 제16권4호
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• pp.63-74
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• 2014

PURPOSES: This research is to evaluate the mechanical performance of different types of Hot Mix Asphalt (HMA) pavement cells prepared for MN/Road field testing section through an extensive experimental analysis of air voids and simple statistical evaluation tools (i.e. hypothesis test). METHODS: An extensive experimental work was performed to measure air voids in 82 asphalt mixture cores (238 samples in total) obtained from nine different types of road cell located in MN/Road testing field. In order to numerically and quantitatively address the differences in air voids among the different test Cells built in MN/Road, a simple statistical test method (i.e. t-test) with 5% significance was used. RESULTS: Similar trends in air voids content were found among the mixtures including conventional HMA, Reclaimed Asphalt Pavement (RAP) and Warm Mix Asphalt (WMA) combined with taconite aggregate this provides support to the use of RAP and WMA technology in the constructions of asphalt pavement. However, in case of acid modified HMA mixtures, significant differences in air void content were observed between on the wheel path and between wheel path location, which implies negative performances in rutting and thermal cracking resistances. Conclusions : It can be concluded that use of RAP and WMA technology in the construction of conventional asphalt pavement and the use of PPA (Poly Phosphoric Acid) in combinations with SBS (Styrene Butadiene Styrene) in asphalt binder production provide satisfactory performance and, therefore, are highly recommended.