• Korean Chemical Engineering Research
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• 제44권3호
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• pp.259-264
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• 2006

염화반응에 의한 $TaCl_5$의 제조에서 반응생성물 중 $NbCl_5$, $TiCl_4$, $FeCl_2$ 등이 주요 불순물로 존재하게 된다. $TaCl_5$와 $NbCl_5$는 증류나 수소 환원법에 의해 쉽게 분리가 되므로, 반응생성물에서 $TaCl_5/NbCl_5$ 혼합물을 99.9％ 이상 순도로 분리하기 위해 2기의 연속식 증류공정을 사용하여 light한 성분과 heavy한 성분을 제거하는 공정을 구성하였다. 본고에서는 순차배열(direct sequence)과 비 순차배열(indirect sequence)으로서의 두 분리공정에 대한 비교연구를 상용성 화학공정모사기인 Aspen Plus 13.1을 이용해서 전산모사를 수행하였다. 비교결과 순차배열이 비 순차배열에 비하여 초기 장치투자비용이나 운전비용에서 좀 더 우수한 것으로 나타났다.

• 설비공학논문집
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• 제27권9호
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• pp.475-483
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• 2015

In Korea, a typically hot and humid summer means that air-conditioners consume a large quantity of electricity; accordingly, the simultaneous usage of an indirect evaporative cooler may reduce the sensible-heat level and save the amount of electricity that is consumed. In this study, the heat-transfer and pressure-drop characteristics of an indirect evaporative cooler made of paper/plastic film were investigated under both dry and wet conditions; for the purpose of comparison, an indirect evaporative cooler made of plastic film was also tested. Our results show that the indirect evaporative efficiencies under a wet condition are greater than those under a dry condition, and the efficiencies of the paper/plastic sample (109% to 138%) are greater than those (67% to 89%) of the plastic sample; in addition, the wet-surface, indirect evaporative efficiencies of the paper/plastic sample are 32% to 36% greater than those of the plastic sample. Further, the wet-surface pressure drops of the paper/plastic sample are 13% to 23% larger than those of the plastic sample, and this might have been caused by the surface roughness of the samples. A rigorous heat-transfer analysis revealed that, for the plastic sample, 30% to 37% of the wet channels remained dry, whereas all of the channels were wet for the paper/plastic sample.

• 대한수의학회지
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• 제32권1호
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• pp.57-61
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• 1992

Borna disease(BD) virus 특이항체검출에 대한 세 가지 혈청진단법(간접형광항체법, 세포효소면역반응법, 혈청중화시험)의 정확도를 비교하기 위해 BD virus를 실험적으로 감염시킨 273수의 토끼의 혈청으로 시험하였다. 혈청중 간접형광항체법에 의하여 판정된 123혈청들은 모두 세포효소면역반응법에 의해서 양성으로 판정되었으나 혈청중화시험법에 의해서는 단지 27혈청에서만 양성으로 판정되었다. 혈청중화시험법은 간접형광항체법과 세포효소면역반응법에 비하여 민감도가 훨씬 낮게 나타나 BD virus의 혈청학적 연구에는 간접형광항체법 및 세포효소면역반응법의 활용도가 높을 것으로 생각된다.

• 전기학회논문지
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• 제67권11호
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• pp.1555-1561
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• 2018

Tracking and detecting targets by the millimeter wave seeker is affected by movement of platform. Stabilization equipments use an inertial sensor to compensate for disturbance of stabilizing gimbal or platform. In the direct line of sight stabilization system, an inertial sensor is mounted on inner gimbal to compensate the disturbance directly, so the performance is excellent and the implementation method is simple. However gimbal design requires somewhat larger volume. Since an inertial sensor is mounted on gimbal base in the indirect line of sight stabilization system, additional space of gimbal is not required for the gimbal design. However, this method does not directly compensate for the disturbance of the line of sight stabilization axis, which can degrade performance. In order to perform the tracking performance, two methods are analyzed for line of sight stabilization performance based on direct and indirect of a 2-axis gimbaled servo system for millimeter wave seeker in this study. The simulation and experimental results validate the performance comparison of two methods.

• Physical Therapy Rehabilitation Science
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• 제12권2호
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• pp.201-205
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• 2023

Objective: Resistance exercise is a necessary element to improve quality of life, and measurement and evaluation of muscle strength provide important information for prescription and management of rehabilitation and exercise programs. This study analyzed the correlation between direct and indirect 1RM for isokinetic maximum torque of the knee joint in order to provide useful information in the field of exercise programs. In addition, the flexion-extension ratio and the difference in left-right deviation were verified. Design: A cross-sectional study Methods: The subjects of this study were 33 healthy adult men and women without medical problems who participated in the health exercise class program at S University in Seoul. The correlation between isokinetic maximum torque and direct and indirect 1RM was analyzed, and a dependent t-test was performed to analyze the flexion-extension ratio and left-right deviation. Results: There was a high correlation between the isokinetic maximum torque and direct and indirect 1RM, and no statistically significant difference was shown between the test methods in the analysis of the flexion-extension ratio and left-right deviation. Conclusions: Isokinetic muscle function measuring equipment is expensive, so it is difficult to use it in local exercise rehabilitation and training sites. Through this study, it was found that direct and indirect 1RM isokinetic maximum torque showed a high correlation, and there was no difference in evaluating muscle function such as flexion-extension ratio and left-right deviation. Therefore, it is considered that the muscle function evaluation using 1RM in general field can be usefully utilized.

• 융합신호처리학회논문지
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• 제13권1호
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• pp.44-49
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• 2012

간접접촉 심전도 측정(Indirect-Contact ECG)은 일상생활에서의 무구속 무자각 측정에 적합한 새로운 심전도 측정 방법이다. 간접접촉 심전도 측정 에 서 관측되는 큰 배경 잡음을 줄이기 위한 기초 연구로서, 본 연구에서는 간접 접촉 심전도에서 사용되는 용량성 결합 능동 전극(Capacitively coupled active electrode)의 열잡음(Thermal Noise) 모델을 구성하였다. 실험을 통해, 용량성 결합 능동 전극만의 배경 잡음의 크기가 열잡음 모델에서 예상한 수준과 거의 일치함을 확인하였다. 면으로 된 직물의 실제의 전기적 특성을 열잡음 모델에 적용하여, 면 위에서 측정된 간접접촉 심전도의 이론적 열잡음을 계산하였다. 이 연구를 통해, op-amp의 내부 잡음(intrinsic noise)은 저항에 의한 열잡음에 비해 무시할 수 있을 정도로 작음을 알 수 있었다. 그리고 열잡음의 크기와 능동 전극의 입력 저항간의 관계를 도출할 수 있게 되어, 능동 전극의 입력 저항의 최적 값 선정을 위한 향후 연구의 기반이 되었다.

• 한국의상디자인학회지
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• 제15권3호
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• pp.1-17
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• 2013

The purpose of this study was to identify the relationships among self-esteem, physical appearance comparison, media concern, sociocultural attitude toward appearance, body attitudes, and life satisfaction. Data were collected from a convenience sample of 232 female undergraduate students. Data were analyzed using factor analysis, correlation, and multiple regression. The result showed that there was a correlation between physical appearance comparison and media concern. Self-esteem, physical appearance comparison, and media concern had an indirect influence on body attitudes through sociocultural attitude toward appearance. Self-esteem and physical appearance comparison had a direct effect on body attitude. All variables did not have an influence on life satisfaction, except self-esteem.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2009년도 추계학술대회 논문집
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• pp.671-672
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• 2009

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2009년도 추계학술대회 논문집
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• pp.673-674
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• 2009

• Archives of Plastic Surgery
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• 제32권3호
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• pp.293-298
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• 2005

Osseointegrated prosthetic auricular reconstruction can be classified as either direct or indirect. In the $Br{\aa}nemark $ system of direct osseointegration, implants are placed into the mastoid process of the temporal bone. In the Epitec system of indirect osseointegration, implants are inserted into a three-dimensional carrier plate that is fixed to the mastoid by means of screws. We experienced forty-four cases using the indirect system and seventeen cases using the direct system. We compared with two systems by complications, such as skin reaction, implant loosening, implant loss. There were no specific differences in the skin reaction around the implants and abutments in relation to age or system used. The degree of skin reaction was different according to the conditions around the implant: in cases of virgin microtia, a skin flap was used to cover the implant, in contrast to grafted skin coverage for failed autogenous reconstruction. In both systems, the skin reaction was more severe and frequent in skin flap than in grafted skin. Loosening of the implant was more frequent in the direct system; however, accidental detachment of the implant from the abutment was more frequent in the indirect system. To reduce complications of skin reaction in osseointegrated prosthetic auricular reconstruction, it is important for soft tissue around implant to immobilize. Therefore, grafted skin is better than skin flap as soft tissue around implant. And immobilization of soft tissue around implant by wound dressing is major facter.