• Computational Structural Engineering
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• v.3 no.3
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• pp.30-38
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• 1990

본 실험은 지금까지 우리나라에서 수행 되어온 기존, 건축 토목관계 실험의 수준을 한차원 높히는데 크게 기여하리라 생각된다. Hydraulic Jack을ㄹ 이용한 1 방향 실험과는 비교할 수 없을 정도로 자동화, 기계화를 이루었으며, 실험에 사용된 Actuator는 미국의 MTS사 제품으로 빠른 속도 (2Hz에서 최대 +/-7.5cm Stroke)로 움직이는 반복 주기 하중을 컴퓨터가 제어하고 Data를 자동적으로 컴퓨터에 기록하므로 구조물의 동적특성까지를 규명하는데 필수적인 장비이다. 또한 Shaking table은 실제로 발생하는 지진파를 그대로 입력시켜 구조물에 대한 내진 성능을 완벽하게 측정할 수 있다. 특히 구조설계자들 사이에도 논란이 되고 있는 우리나라 내진규준의 R factor(반응수정계수)를 정하는데 매우 유효한 역할을 하리라 기대된다.

• Journal of Biomedical Engineering Research
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• v.20 no.2
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• pp.139-148
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• 1999

In this paper, we designed the dental surgery system based on PC. This system predict post operated 3-dimensional image, So the patient has no need to take CT after surgery and expose his body to radiological damage. We predict the post operated skull from the patient's CT with pre and post cephalometry X-ray. Our novel procedures, to register X-ray and CT, are based on anatomical landmarks, singular value decomposition. And we display the predicted image 3-dimensionally by surface rendering. We verified this system by dry skull experiment and clinical experiment. When significance level is 0.05, there is on significance.

• Journal of Science Education
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• v.37 no.3
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• pp.417-433
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• 2013

The purpose of this study was to analyze 'how STEAM activities affect students' science process skills and science-related attitudes'. For more accurate, we have set 31 sixth-grade students from Gyeong-gi Province as an experiment group, and another 31 as a comparative group. We developed a STEAM program based on the educational concepts: Creative Design and Emotional Touch. Through pre-post experiment design, we have introduced TSPS, and Test of Affective Aspects. For TSPS, the comparative group scored higher average grade before the process. After the process, however, the experiment group exceeded the other. The result was considerable enough to verify that the science process skills were bolstered through the STEAM program(p<.05), Similar result was derived regarding the science related attitude. Students in the comparative group originally showed higher degree of interest to science. When the STEAM program was carried out, the standing reversed. The increase in the number of science related attitude indicates the program valid(p<.001). Furthermore, when we asked the students who participated in the experiment how they recognized the STEAM activity, we received positive answers: they consider the program efficient and well suited to the class environment. Conclusively, the STEAM program was proven to be effective for improving science process skills and attitude, and was perceived affirmative.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.4
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• pp.337-345
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• 1991

This study was designed to investigate the effects of dietary protein ana calcium levels on hematological properties and renal functions of the Pb-administered rats. Male Sprague-Dawley rats were assigned to a 3$\times$3$\times$2 factorial design with 3 levels of protein (40％, 16％, 6％), 3 levels of Ca (1.2％, 0.6％, 0.12％) and 2 feeding Periods (3 and 7 Weeks). The Control group was included separately, The rats were exposed to the drinking water containing 2, 000ppm of lead. Hematocrit, hemoglobin content and RBC count were lower in the Pb-added groups than in the control group and were reduced with decreasing dietary protein and Ca levels. Urinary-aminolevulinic acid was higher in the Pb-added groups than in the control group and increased with decreasing dietary Ca level. However, urinary glucose was higher in the Pb-added groups than in the control group and enhanced with decreasing dietary protein and Ca levels. Creatinine celarance was not affected by the Pb administration when the rats fed the diet containing sufficient protein and Ca.

• The KSFM Journal of Fluid Machinery
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• v.3 no.1 s.6
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• pp.43-50
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• 2000

Upgrade development of a high pressure ratio centrifugal compressor in marine engine turbochargers is presented. A new matched operating point at increased speed of rotation was determined through system cycle analysis using the exisitng test data of turbine performance. Under some severe restrictions for geometric parameters, the state-of-the-art methods of both aerodynamic design and CFD analysis were applied, in which only an impeller, a vaned diffusor and some part of casing wall were modified. Prototype hardware was fabricated and assembled for system performance tests. Excellent performance in pressure ratio and efficiency was obtained over whole speed region. Reduced surge and choke margin was, however, observed at design speed of rotation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4729-4735
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• 2014

To protect the environment, the regulation of emissions from off-road engines which are relatively neglected, is being reinforced. This paper deals with the robust design of off-road diesel engines considering the emission characteristics. Measurements of the NOx and PM levels based on the DOE were carried out. The injector hole number, injection timing and EGR rate were selected as the control factors. The orthogonal arrays table $L_9(3^3)$ was made from 2 or 3 levels for each factor and measurements of emissions were accomplished based on the table. The small-the-better SN ratio according to the Taguchi method was evaluated. The ANOVA (analysis of variance) for the SN ratio was conducted. The injection timing on the NOx emissions and the EGR rate on the PM have the largest effect on the low-load operation condition. The confidence levels of the control factors were more than 90%.

• Korean Journal of Poultry Science
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• v.39 no.3
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• pp.195-205
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• 2012

The objective of this study was to evaluate the effects of different levels of dietary ME on growth performance and carcass characteristics in two different strains of broiler chicken. A total of one thousand, 1-day-old A strain and R strain male chicks were randomly assigned into 8 treatments in a $2{\times}4$ factorial arrangement. They were fed iso-nitrogenic (CP 21%) crumbled diets formulated to contain metabolizable energy (ME) 2,950 to 3,250 kcal/kg in increment of 100 kcal/kg in the starter phase (1 to 21d) and iso-nitrogenic (CP 19%) pelleted diets containing same ME levels as in the finishing phase (22 to 38d). The body weight (BW) gain of chicks fed the lower ME diets (2,950 or 3,050 kcal/kg) were higher than those of the higher ME groups. The dietary energy level showed significant effects on feed intake and feed conversion rate (FCR) from 1 to 38 days of age (p<0.05). With the increment of dietary energy, feed intake tended to be reduced, whereas FCR was improved in the two strains of broiler chickens. The lowest FCR was observed at 3,250 kcal/kg diet groups in both of the two strains from 1 to 38 days of age. Feed intake and BW gain during 38 days were significantly affected by the strain factor. Increasing dietary energy up to 3,250 kcal/kg had no effect on the relative weights of breast meat and abdominal fat. The dietary energy and strains showed significant effects on the dressing percentage. There were no significant differences in various blood profiles except for GPT activity.

• Journal of Scientific & Technological Knowledge Infrastructure
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• s.2
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• pp.100-101
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• 2000

최근 분자모델링을 이용한 신물질설계기술 (Computer Aided Material Design)이 재료과학이나 생명과학분야의 획기적인 성공사례를 통하여 신물질개발연구에 실제적인 도움을 줄 수 있는 매우 효율적인 방법이라는 인식이 보편화되었다. 최근 미국, 유럽 등 기술선진국에서는 신제품 개발시 기존의 실험적인 연구가 아닌 모델링 방법의 분자설계기술을 이용하여 신약이나 기능성 첨단소재 등의 개발로 엄청난 부가가치를 창출하고 있다. 과학적 기반이 열세이고, 사업기술의 수준이 상대적으로 중간적 지위에 있는 우리나라는 신물질 및 신제품 개발을 위한 첨단기반기술의 확보가 다가오는 21세기 국가산업경쟁력 제고에 필수적이라는 인식 아래 분자설계 개발연구센터는 산업자원부의 기술혁신센터(Technology Innovation Center)로 지정받아 컴퓨터 모델링을 이용한 화학신소재 분차설계기술 보급에 힘쓰고 있다. 산업체에 첨단기술 보급을 위하여 기술혁신센터를 운영하고 있으며 또한, 초고속정보망기술지원실에서 정보통신부의 지원으로 올해 '3차년도 초고속응용기술지원사업'을 수행하고 있는 숭실대학교 분자설계연구센터의 소장인 노경태 교수를 찾아보았다.

• ETRI Journal
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• v.14 no.4
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• pp.165-178
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• 1992

본 고는 Mini-MAP 네트워크의 접속장치를 구현한 내용이다. 이 접속장치는 공장자동화 네트워크 시스팀에서 Mini-MAP 노드로 동작하며, PLC, CNC, robot와 같은 프로그래머블 디바이스를 MAP 네트워크 환경에 접속하여 원격제어가 가능하도록 하는 네트워크 구축을 위한 핵심 장치이다. 이 접속장치는 MAP 3.0의 Mini-MAP으로 구현하고 실현하였다. MAC 부계층은 Token Bus Controller(TBC)가 담당하며, LLC 부계층은 class 3로 설계하였고, MMS는 implementaton class MAP3를 설계하였다. 구현된 모든 소프트웨어는 Mini-MAP의 실시간 정보 전송 성능을 보증하기 위해 real-time 멀티 태스크 OS로 운영하도록 설계하였으며, 보드에 firmware로 탑재하였다. 프로토콜 분석기를 이용하여 LLC 수준의 오류검출과 전송기능을 확인하였으며, MMS는 적합성 시험을 이미 받은 MMS를 탑재한 상용 제품과의 통신 실험을 통해 적합성을 확인하였다.

• Journal of the Korean Society for Library and Information Science
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• v.32 no.3
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• pp.207-230
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• 1998

Because of a rapid increase of information available through web site, a user often falls into confusion of which web sites should be visited for his information needs. If a web site search engine can classify web sites according to their subject or topics, it can help the user to determine which web sites are worth accessing and thus to easily acquire relevant information. In this study, I propose new classifying system with a two level hierarchy and 57 items.