• 한국대기환경학회지
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• 제13권6호
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• pp.475-486
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• 1997

The characteristics of atmospheric aerosols were investigated as a function of particle size and water solubility. The atmospheric aerosols were sampled with classifying into 12 size ranges by the use of Andersen low-pressure impactor. Collected aerosol particles were extracted by ultrapure water and filtered to be separated into water-soluble and insoluble components. The concentrations 12 elements in both components were determined by PIXE analysis. And the concentrations of 8 ions in the soluble component were analyzed by ion chromatography. In general, the mass size distribution of particulate matter was represented as a bimodal distribution. The mass size distributions of S$(SO_4^{2-}), K(K^+), Zn and NH_4^+$ skewed to the smaller size range and those of Si, Ca$(Ca^{2+}), Fe, Na^+ and Mg^{2+}$ skewed to the larger size range. They had roughly one peak in the fine and coarse particle region,respectively. On the other hand, the mass size distribution of Ti, Mn, Ni, Cu, $Cl^- and NO_3^-$ were represented as the bimodal distribution. Fe and Si in the aerosol particles extracted into pure water are existing in high insoluble state. Conversely, almost the whole of S is dissolved in water.

• 한국컴퓨터정보학회논문지
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• 제3권3호
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• pp.129-137
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• 1998

국민경제에서 중소기업이 차지하고 있는 비중은 계속 증가하고 있는 가운데 중소기업의 경영상의 애로점으로 자금 조달의 문제가 가장 심각한 것으로 지적되고 있다. 본 연구는 중소기업의 경영 문제 가운데 재무구조의 실태를 파악하고 이를 대기업 또는 우리나라산업평균 재무비율과 비교함으로써 중소기업의 재무안정성 비율을 분석한 것이다. 조사 분석 결과 전체적으로 산업별 표준비율에는 그 수준이 미치지 못하고 있으나 산업평균과 비교할 때 그 수준이 양호한 것으로 조사되었으며 산업평균에 비해 안정성과 유동성이 양호한 반면 차입금 의존도가 대단히 낮은 것으로 조사되어 국가 또는 행정 자치적인 측면에서 중소기업 자금 지원 정책이 개발되어야 할 것으로 인식되었다.

• Archives of Reconstructive Microsurgery
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• 제8권1호
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• pp.77-83
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• 1999

전북대학교병원 정형외과에서 1993년 8월부터 1997년 8월까지 족부 및 수부 손상 5례에 대하여 족 배 유리 피부판 이식술을 시행하고, 1999년 3월까지 최소 19개월부터 최장 67개월간 추시하여 다음과 같은 결과를 얻었다. 1. 나이별로는 9세부터 35세까지로 평균 23세 이었으며, 성별로는 전례가 남자이었으며, 족부에서 시행하였던 예가 4례, 수부에서 1례이었다. 2. 족부의 손상 원인은 교통사고 2례, 기계 사고 1례, 자전거 바퀴 사고 1례 이었으며, 수부에서는 교통사고에 의하여 전완부 요골의 개방성 골절이 동반되고 수부 배부의 다발성 신전 건 파열 및 피부 괴사에 의한 신전 건 노출 1례이었다. 3. 수여 동맥은 족 배 동맥 2례, 전 경골 동맥 1례, 후 경골 동맥 1례 그리고 척골 동맥이었으며, 수여 정맥은 족부 4례에서 2개 정맥을 문합하였으며, 5례(100%) 전례에서 성공하였다. 4. 추시 결과 유리 피판 이식술 후 외양(exterior)과 일상생활시 피부판이 손상되는 분쇄(maceration) 정도는 우수하였으나, 감각 회복 정토는 불량하였다. 5. 제공 부위인 족 배부는 유리 피판 이식술 3주 후 전층 식피술을 시행하여 완전 접착되었으며, 추시상 유병율없이 우수한 결과를 보였다.

• Restorative Dentistry and Endodontics
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• 제14권1호
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• pp.189-197
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• 1989

The purpose of this study was to observe the resulting canal shape after using hand, sonic and ultrasonic instrumentation. Thirty canals from extracted human upper or lower 1st and 2nd molars were divided into 3 groups: hand, sonic and ultrasonic instrumentation group. 10 canals of each group were individually prepared with one of three instrumentation methods. After instrumentation and histological processing, apical, middle and coronal third cross sections were examined on the roundness of the canal by microscope. The result were as follows. 1. All experimented groups showed no significant difference in canal roundness regardless of size and level of the canal. 2. Sonic air instrumentation groups revealed Significantly better canal roundness than ultrasonic groups at the middle third of the fine canal. 3. In ultrasonic instrumentation groups, the roundness of the large canal was significantly better than that of fine canal.

• 한국의류산업학회지
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• 제6권5호
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• pp.634-640
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• 2004

Nowadays, the use of apparel CAD system is important to the mass production of ready to wear. Especially, computer-based grading is the most important process to improve the fitness of clothes and to reduce the time needed to make various size pattern. The purpose of this study was to suggest a standard sizing system for high school boys' pants and to suggest a grading method according to the sizing systems. The subjects were 217 high school boys of 16 to 18 year-old. The size intervals of waist girth and hip girth were 3 cm and 4 cm respectively. The sizing system, which had frequencies more than 4%, was classified 8 cases. Among them, 71-92 and 71-88 size were the most frequent size and were adopted the basic size for the two types of grading. According to the sizing system, hand-made patterns were manufactured. By measure of the each part of the slacks, 4 size's new grading-rule patterns were developed by each size. This result will contribute to clothing fitness of consumer and the amount of production.

• 한국의류학회지
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• 제24권3호
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• pp.289-300
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• 2000

Stretchable textile materials are getting more widely used in clothing industry. Among others are two obvious reasons which make it so desirable to young female customers, i.e., better confort with motion and more closely fitted silhouette. But these two points cannot get along well always. If a manufacturer try hard to make his products too closely fit, then the products are even less comfortable than made of non-stretchable material. On the other hand, if a stretchable garment are developed to be too comfortable with plenty of size tolerance. it cannot attract customers who are looking for something closely fit. So the study was aimed to investigate appropriate size tolerances.

• Archives of Reconstructive Microsurgery
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• 제6권1호
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• pp.87-95
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• 1997

Traumatic injury to the hand often leads to soft tissue defects with exposed tendons, bones, or joints. Though many new flap have been introduced, the choice of flap that would be best for the patient depends on such factors as the site, size, and degree of wounds. Additionally the selected surgical method should be yielded cosmetic and functional superiority by the one-staged reconstruction. In our experience, small to medium sized soft tissue defect with bone and tendon exposure of hand can be resurfaced with an arterialized venous free flap from the volar aspect of distal forearm. Wide and deep defects of the hand can be covered with a sensory cutaneous free flap such as the medial plantar free flap, dorsalis pedis free flap, and radial forearm free flap. Specialized flap such as wrap-around flap, toe-to-finger transfer, onychocutaneous free flap can be used for the recontruction of defect on the thumb and finger. Based on the above considerations and our clinical experience of 60 free flap cases of the hand, the various methods for the proper repair of soft tissue defects of the hand are described. And we obtained satisfactory functional and cosmetic results with 95% success rate of free flap.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제1권3호
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• pp.177-186
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• 2012

본 논문에서는 실시간 손동작 분석을 위한 깊이정보 기반 손 영역 검출 및 추적 방법을 제안한다. 이를 위해 손 영역 검출단계에서는 깊이정보만을 이용하여 손 영역의 특징인 형태모델을 생성하고, 검출 시 움직임 정보와 영역 확장(Region Growing)을 통해 객체를 추출한다. 추출된 객체는 사전에 생성된 형태모델과 크기정보를 분석하여 최종 손 영역으로 판정한다. 판정된 손 객체는 추적단계에서 중심점 전이 과정을 통해 이전 중심점과의 최근접점을 획득하고, 최근접점으로부터 영역 확장과 깊이기반 적응적 평균 이동 기법(DAM-Shift)을 통해 새로운 중심점을 검출하여 추적한다. 마지막으로 성능 검증을 위해 다양한 손 모양과 속도 및 위치에 대한 다양한 환경에서 실험하고, 검출속도와 추적된 궤적의 정량적, 정성적 분석을 통해 제안하는 방법의 효율성을 입증한다.

• 한국세라믹학회지
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• 제29권1호
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• pp.65-73
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• 1992

The effect of grain size on the time-dependent piezoelectrice degradation of a poled PZT of MPB composition Pb0.988Sr0.012 (Zr0.52Ti0.48)O3 with 2.4 mol% of Nb2O5 was studied, and the degradation mechanism was discussed. Changes in the internal bias field and the internal stress both responsible for the time-dependent degradation of poled PZT were examined by the polarization reveral technique, XRD and Vickers indentation, respectively. The piezoelectric degradation increased with increasing time and grain size, and the internal bias field due to space charge diffusion decreased with increasing grain size of poled PZT. The internal bias field, however, was almost insensitive to the degradation time regardless of the grain size. On the other hand, both the x-ray diffraction peak intensity ratio of (002) to (200) and the fracture behavior including the crack propagation support that the ferroelectric domain rearrangement of larger grain size showed rapid relaxation of the internal stress compared with smaller one, which is thought the origin of the larger piezoelectric degradation in the former. In conclusion, the contribution of space charge diffusion on the piezoelectric degradation of PZT is strongly dependent on both the grain size and the composition. Thus, the relaxation of internal stress due to the ferroelectric domain rearrangement as well as the amount and time-dependence of the internal bias field due to space charge diffusion should be considered simultaneously in the degradation mechanism of PZT.

• International Journal of Fluid Machinery and Systems
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• 제7권2호
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• pp.60-67
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• 2014

In order to clarify the effect of inlet bellmouth size of semi-opened type axial fan on its performance and flow fields around rotor, fan test and flow field measurements using hotwire anemometer were carried out for 6 kinds of bellmouth size. As results of fan test, the shaft power curve hardly changed, even if the bellmouth size changed. On the other hand, the pressure-rise near best efficiency point became small with the bellmouth size decreasing. Therefore, the value of maximum efficiency became small as the bellmouth size decreased. As results of flow field measurements at fan inlet, the main flow region with large meridional velocity existed near blade tip when the bellmouth size was large. As bellmouth size became smaller, the meridional velocity at fan inlet became smaller and the one at outside of blade tip became larger. As results of flow field measurements at fan outlet, the main flow region existed near rotor hub side.