• 항공우주기술
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• 제3권2호
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• pp.238-247
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• 2004

실시간 시뮬레이션 및 HILS(Hardware In the Loop Simulation)는 항공기 설계 및 개발에 있어서 개발기간의 단축과 비용절감 측면에서 필수적이며 컴퓨팅 기술의 발달로 그 중요성이 더욱 부각되고 있다. 복잡한 운동모델과 실시간 시뮬레이션에 대한 요구사항을 충족시키기 위하여 분산처리에 의한 시뮬레이션이 요구되며 실시간 컴퓨터 환경 내에서 시뮬레이션 소프트웨어를 개발해야 하므로 개발 및 디버그, 유지보수가 매우 어렵다. 특히 실시간, 무 교착상태의 고성능 분산코드를 작성하는 경우는 더욱 그러하다. 본 연구에서 구축하는 회전익기 HILS 환경은 이러한 어려움을 상당부분 처리함으로써 사용자가 직접 코드를 손대지 않고 HILS 및 시뮬레이션을 수행할 수 있도록 상용화된 부품과 개발된 최신 툴을 이용하여 구성하였다. Matlab/Simulink 환경에서 개발된 회전익기 비행시뮬레이션 소프트웨어를 기준으로 하여 HILS 환경 및 MILS(Man In the Loop) 환경이 추가되어 조종사의 직접 입력에 대한 반응을 실제 하드웨어에 피드백 하는 MILS-HILS 통합 환경을 구축하였다. 개발기간의 단축 및 유지보수의 편의를 위하여 RT-Lab을 사용하여 실시간 코드를 생성하고 타켓컴퓨터에 다운로드 하는 방식으로 실시간 시뮬레이션이 가능하다.

• Journal of Microbiology and Biotechnology
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• 제14권2호
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• pp.417-421
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• 2004

A normal prion protein (PrPc) is converted to a protease resistant isoform (PrPsc) by an apparent self-propagating activity in bovine spongiform encephalopathies (BSE), which is a neurodegenerative disease. The cDNA encoding bovine PrP open reading frame (ORP) in Korean cattle was cloned by polymerase chain reaction (PCR). The cloned cDNA had a length of 795 base pairs which coded for a protein of 264 amino acid residues with a calculated molecular mass of 28.6 kDa. Identities of 90, 90, 79 and 78% on nucleotide and 94, 94, 84, and 84% on amino acid sequence were shown to PrP genes from sheep, goat, human, and mouse, respectively. The cloned DNA was ligated into the pQE30 expression vector and transformed into E. coli M15. The PrP was expressed by induction with isopropyl-$\beta$-D-thiogalactoside (IPTG) and purified on the Ni-NTA affinity column. High specific activities of the recombinant PrP were observed in the fraction of pH 5.8 eluate and showed a molecular mass of-29 kDa on SDS-PAGE and Western blot analysis.

• 한국강구조학회 논문집
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• 제8권4호통권29호
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• pp.85-94
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• 1996

This paper investigated structural behaviors of joint of concrete filled steel tube column and P.C reinforced concrete beam through a series of hysteretic behavior experiment. The results are summarised as follows: (1) The joint stiffness of concrete filled square steel tube column and P.C reinforecd beam was higher than that of concrete filled circular steel tube column and P.C reinforecd beam, and it was decreased as the increase of the number of hysteretic cycle. (2) The aspects of the hysteretic behavior in the joint was stable as the increase of the number of hysteretic cycle, and rotation resisting capacity of joint of concrete filled square steel tube column and P.C reinforced concrete beam was higher than those of the concrete filled circular steel tube column and P.C reinforced concrete beam. (3) Some restriction must be put upon the ratio of axial force in this joint model because the load carrying capacity was decreased by flexural and flexural-torsional buckling in case of the ratio of axial force 0.6. (4) The emprical formula to predict the ultimate capacity of joint model to superimpose shearing strength of steel web(H section) and bending strength of reinforced concrete beam was expected.

• 간호행정학회지
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• 제11권3호
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• pp.289-301
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• 2005

Purpose: This study was to examine the ego-identity of nursing students and their adjustment to home and university in an effort to identify the correlation of their ego-identity to their adjustability and lay the foundation for providing better personality education to them. Method: The subjects in this study were 400 nursing students at H and S universities in south Chungcheong province. The instruments used in this study were Park A-cheong(2003)'s Korean-version Ego-Identity Inventory and Jeong Jonggweon(1998)'s Home and School Adjustment Inventory. For data analysis, SPSS/PC+ Package was used, and statistical data on frequency and percentage were obtained. Besides, t-test, one-way ANOVA and Pearson correlation coefficient were employed. Result: The findings of the study were as follows: The nursing students investigated got a 3.46 and 3.53 in ego-identity and family life adjustment respectively out of possible five points, which were both above the average. Their score in school adjustment was 2.89, which wasn't high. As for connections between general characteristics and ego-identity, their academic school year, their type of residence, presence or absence of parents and their birth order made no statistically significant differences to their ego-identity. But as to motivation of choosing nursing, the students who chose their major at their own option were the best in that regard. Their adjustment to family life made no significant differences, and regarding school adjustment, ego-identity was better among those who lived in a lodging house or dormitory(F=4.01, p<.05) and who chose their major at their own option(F=4.88, p<.01). In addition, those with better ego-identity were better adjusted to home and school. Conclusion: As the above-mentioned findings suggested that nursing educators should teach students by mapping out specific plans to enhance the ego-identity of students and facilitate their school adjustment, and full-fledged nurses should be produced by teaching students to build the right work ethics and become qualified as a professional.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2003년도 추계국제학술대회
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• pp.181-181
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• 2003

We have studied the mechanism of action of TCDD on CYP1A1 promoter activity in both Hepa Ⅰ and MCF-7 cells using transient transfection system with p1A1-Luc reporter gene. When HDAC inhibitors, such as trichostatin A, HC toxin and a novel HDAC inhibitor, IN2001 were cotreated with TCDD to the cells transfected with plAt-Luc reporter gene, the basal promoter activity of CYP1A1 was increased by HBAC inhibitors. Also, in MCF-7 human breast cancer cells, HDAC inhibitors, such as IN2001 and trichostatin A increased the basal activity of CYP1A1 promoter but TCDD stimulated CYP1A1 promoter activity was not changed by HDAC inhibitors. And, in stably-transfected Hepa Ⅰ cells with p1A1-Luc, HDAC inhibitors increased the basal promoter activity only Also, we have investigated the effects of HDAC inhibitors on the human breast and prostate cancer cells in terms of cell proliferation and apoptosis based on SRB assay. IN2001 as well as trichostatin A inhibited the MCF-7, MDA-MB-231, MDA-MB-468, T47D, ZR75-1, PC3 cell growth dose-dependently. The growth inhibition of these cells with HDAC inhibitors was associated with profound morphological change, which suggests the HDAC inhibitors induced apoptosis of cells. The result of cell cycle analysis after 24h exposure of IN2001 showed G2/M cell cycle arrest in MCF-7 cells and apoptosis in T47D and MDA-MB-231 cells.

• Journal of Periodontal and Implant Science
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• 제53권1호
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• pp.2-19
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• 2023

Purpose: Surgical techniques in orthodontics have received widespread attention in recent years. Meanwhile, biomaterials with high molecular content have been introduced, such as platelet concentrates (PCs), which may accelerate orthodontic tooth movement (OTM) and reduce periodontal damage. The present systematic review aimed to answer the following PICO question: "In patients in whom orthodontic surgical techniques are performed (P), what is the effectiveness of using PCs over the surgical site (I) when compared to not placing PCs (C) to achieve faster tooth movement (O)?" Methods: A search was performed in 6 databases. The criteria employed were those described in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses declaration. The present review included studies with a control group that provided information about the influence of PCs on the rate of OTM. Results: The electronic search identified 10 studies that met the established criteria. Conclusions: The included studies were very diverse, making it difficult to draw convincing conclusions. However, a tendency was observed for OTM to be accelerated when PCs were used as an adjuvant for canine distalization after premolar extraction when distalization was started in the same session. Likewise, studies seem to indicate an association between PC injection and the amount of canine retraction. However, it is not possible to affirm that the use of PCs in corticotomy shortens the overall treatment time, as this question has not been studied adequately.

• 한국대기환경학회지
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• 제22권4호
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• pp.451-458
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• 2006

Automotive exhaust is suspected to be one of the major reasons of the rapid increase in greenhouse effect gases in ambient air. As the concerns regarding global worming were increased, the pressure on mobile source greenhouse gas (GHG) emission were also increased. Carbon Dioxides contribute over 90% of total GHG emission and the mobile source occupies about 20% of this $CO_2$ emission. In this study, in order to investigate $CO_2$ emission characteristics from gasoline and LPG passenger cars (PC), which is the most dominant vehicle type in Korea, 53 vehicles were tested on the chassis dynamometer. $CO_2$ emissions and fuel consumption efficiency were measured. The emission characteristics by fuel type, model year, mileage, vehicle speed and transmission type were also discussed. Test modes used in this study were NIER 10 modes and CVS-75 mode, which have been used for developing emission factors and testing new vehicles respectively. The results of this study showed that the main factors which have significant influences on the $CO_2$ emissions are fuel type, transmission type, displacement of vehicle and mileage. The correlation between $CO_2$ emission and FE was also determined by comparing $CO_2$ emission and fuel consumption efficiency. The overall results of this study will greatly contribute to domestic greenhouse gas emissions calculation and designing national strategies for climate change.

• Journal of Biosystems Engineering
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• 제16권4호
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• pp.384-398
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• 1991

본 연구는 개별농가(個別農家), 영농단(營農團), 위탁영농회사(委託營農會社)의 농기계 적정투입모형(適正投入模型) 선정(選定)과 보유기종(保有機種)이나 구입희망기종((購入希望機種) 의 경제성을 분석(分析)할 수 있는 대화식(對話式) 시뮬레이션 프로그램을 개발(開發)하고자 수행(遂行)되었으며, 그 결과(結果)를 요약하면 다음과 같다. 가. 농기계(農機械)의 적정투입(適正投入) 규모(規模) 선정(選定) 경제성(經濟性) 분석(分析)의 현실(現實) 적용성(適用性)을 높이기 위하여 투입(投入) 농기계(農機械)의 부담면적(負擔面積) 결정요인(決定要因)과 비용분석을 위한 기초자료를 문헌(文獻) 및 자료조사(資料調査)를 통하여 수집하였으며 이를 기초로 하여 수학적 모델을 개발하였다. 나. 개별(個別) 농업경영체(農業經營體)(농가(農家) 또는 영농단(營農團))의 지역(地域), 기후지대별(氣候地帶別) 적기작업기간에 따른 농기계이용(農機械利用) 일수(日數), 임작업료(賃作業料) 등을, 농촌지도소에 보급된 행정전산용(行政電算用) PC를 이용(利用)하여, 프로그램 이용자(利用者)가 입력설정(入力設定)하고 투입농기계의 경제성(經濟性)을 분석(分析)할 수 있는 대화식(對話式) 프로그램을 개발(開發)하였다. 다. 개발된 프로그램을 이용하여 벼농사 일관작업(一貫作業)은 물론 각 농작업(農作業)을 분리(分離)하여 투입 농기계별로 상세(詳細)한 경제성(經濟性)을 분석(分析)할 수 있으며, 경운 정지작업 기종은 3형식, 이앙(移秧), 방제(防除), 수확작업(收穫作業) 기종은 2형식을 동시(同時)에 분석(分析)할 수 있다. 벼농사는 경운(耕耘), 정지(整地), 방제작업(防除作業)에 대하여 분석할 수 있다. 라. 프로그램 분석결과(分析結果)는 입력(入力)된 경지면적(耕地面積)에서 기계화 영농을 수행할 때 투입 농기계의 기계사용(機械使用) 과부족일수(過不足日數), 부담면적(負擔面積), 손익분기면적(損益分岐面積), 월간(月間) 고정비(固定費), ha당(當) 기계이용비(機械利用費) 등을 포함한다. 마. 손익분기면적(損益分岐面積) 기종별(機種別) 임작업료(賃作業料)를 기준으로 한 손익분기면적(損益分岐面積)은 경운(耕耘) 정지작업(整地作業)의 임작업료(賃作業料)가 100원/평 일때 경운기, 트랙터 22,25,35,38,50,74 마력은 각각(各各) 1.8, 6.7, 7.6, 9.7, 9.3, 17.5, 23.7 ha 였으며, 이앙작업(移秧作業)의 임작업료(賃作業料)가 100원/평일 때 이앙기 보행4조, 승용4,6조는 각각(各各) 2.2, 5.8, 7.9 ha, 수확작업(收穫作業)의 임작업료(賃作業料)가 130원/평 일때 바인더, 콤바인 2,3,4조는 각각(各各) 2.2, 7.2, 10.2, 15.7 ha로 나타났다.

• Tuberculosis and Respiratory Diseases
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• 제48권2호
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• pp.203-209
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• 2000

연구배경: 위식도역류는 정상인 보다 천식환자에서 약 30-85% 정도 높다. 최근 운동에 의해 위식도역류가 증가한다는 보고를 통해 운동시 증가하는 위식도역류가 운동유발생 천식의 발생에 기여하는지 알아보고자 본 연구를 시행하였다. 방 법: 운동유발성 천식의 기왕력이 있는 18명의 환자를 대상으로 운동부하검사와 식도내 pH측청, 운동 전후의 폐활량 검사를 시행하여 위식도역류와 운동유발성 천식을 판정하였다. 본 연구에서는 운동유발성 천식과 기관지천식과의 연관성을 알아보기 위해 메타콜린 기도 유발시험(methacholine bronchial provocation test, MBPT)을 시행하여 대상환자를 운동유발성 및 메타콜린 과민성 천식군(Group I, EIA and methacholine hypersensitive asthma group), 운동 유발성 천식군(Group II, EIA group), 대조군(Group III)으로 분류하였다. 결 과: 전체 18명의 환자 중 남자는 6 명, 여자는 12명이었고, 이들의 평균 연령은 41.1 세이었다. 본 연구에 참가한 모든 환자는 병력상 운동유발성 천식을 의심할 만한 기왕력을 갖고 있었으나, ${\Delta}FEV_1$이 20% 이상 감소한 환자는 대상 환자 18명중 15명이었다. 대상 환자 중 ${\Delta}FEV_1$이 20% 이상 감소한 15명을 대상으로 시행한 MBPT 결파상 PC20 값이 8 mg/ml 이하에서 $FEV_1$이 20% 이상 감소하여 기관지천식으로 진단된 환자는 12명이었으며, 나머지 3 명은 음성을 보여 운동유발성 천식(Group II)으로 판정하였다. 전체 18예 모두 운동 전에는 의미있는 식도내 pH 감소는 없었으며 운동 후 5예에서 식도내 pH 4 이하로 60초 이상 감소하고, pH 4 이하의 시간 백분율이 7.0% 이상을 보여 위식도역류성 질환으로 진단하였으며, 이중 3예는 Group 1 이었고, 나머지 2예는 Group II이었다. 결 론: 본 연구에서 운동유발성 천식 환자에서 위식도역류의 빈도는 33.3%(5/15) 이었다. 모두 5 명의 환자에서 위식도역류가 관찰됨으로써 위식도역류가 다른 여러 요인들과 더불어 운동유발성 천식의 병태생리의 한 요인으로 작용할 수 있다는 가능성을 완전히 배제할 수는 없었다. 이러한 이유로 운동유발성 천식 환자들의 진단 및 치료시에 위식도역류에 대한 관심을 갖는 것이 의미있을 것으로 생각되나, 앞으로 더 많은 연구를 통해 이에 대한 검증이 필요할 것으로 사료된다.

• Journal of Periodontal and Implant Science
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• 제25권1호
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• pp.167-178
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• 1995

It has been believed that the increased release of free oxygen radicals and their tissue damaging potency might be a contributing factor in the pathogenesis of periodontal disease. Antioxidant enzymes such as superoxide dismutase(SOD) and catalase can protect the tissue damage from the free oxygen radicals($O_2^-,H_2O_2$, and $OH^-$). In order to investigate the SOD- and catalase - activity in the blood plasma and red blood cells(RBCs) of the patients with perodontitis, 19 male periodontitis patients($25{\sim}35$ years old) who had good general health, more than 10 teeth with severely inflamed gingiva, attachment loss more than 6mm and bone loss were selected as periodontitis group, and 13 male volunteers($22{\sim}29$ years old) with good general and periodontal health were selected as normal group. After blood plasma and RBC were separated from peripheral blood of 2ml collected from antecubital vein of each subject, SOD- activity in blood plasma and RBCs was measured by the same method that Paoletti et al. did, and catalase - activity in RBC was measured by the same method that Beers et al, did. The difference of SOD- and catalase - activity between the normal and the periodontitis groups was statistically analyzed by Student t-test with SPSS/PC program.The results were as follows : 1. SOD activity in blood plasma was significantly lower in the periodontitis group($1.986{\pm}0.893$) than in the normal group($3.324{\pm}1.044$)(p<0.05). 2. There was no statistical significance in the difference of SOD- activity in RBCs between the periodontitis group($7.753{\pm}3.206$) and the normal group($8.116{\pm}1.192$)(p$242.8{\pm}45.6$) than in the normal group($280.2{\pm}32.6$)(p