Pipe 및 Hose Ass'y 생산시스템 공정최적화 설계 연구

윤철호,이수완 선문대학교·중소기업기술지원연구소 1998 선문공대 연구/기술 논문집 Vol.3 No.1

자동차 에어콘 부품인 Pipe 및 Hose 조립 공정의 생산성을 향상시키기 위하여 공정분석을 실시하였다 시간 연구법에 의해 대상 공정인 5개의 Pipe 및 Hose Ass’y공정에 대한 관측을 하였고. 그 결과 공정별 요소작업및 요소작업별 표준시간을 설정하였다 표준시간을 기초자료로 활용하여 line balancing을 실시한 결과 공정을 재배치 하게되면 공정의 균형 손실이 현저하게 줄어든다는 것을 알 수 있었다. Process analysis was conducted to improve productivity of the automobile airconditioner parts assembly lines. First, five pipe and hose assembly lines were observed by time study methodology. Using the results, element works of target assembly lines and standard time of element works were fixed. Next, line balancing methodology was utilized to evaluate current productivity of target process and layout status The results suggested remarkable line balancing effects when target process relocated

서비스 공정성이 고객만족과 관계품질에 미치는 영향

윤경산,주철수,윤만희 大邱大學校 社會科學硏究所 2001 社會科學硏究 Vol.9 No.1

이 연구의 목적은 관계 마케팅에 있어 지각된 서비스 공정성의 결정적인 역할에 대해 이해하고자 하는 것이다. 본 연구는 서비스 공정성과 관계 마케팅 변수들(관계품질과 고객만족)의 관계, 그리고 고객만족과 관계품질의 연결에 대해 검증하였다. 자료는 대구에 소재한 멤버십 할인매장을 방문한 고객들 중 250명을 분석의 대상으로 하였고, 다중 회귀분석은 만족스러운 모델 적합도를 보여주었다. 제안된 가설들 중 6개의 가설이 통계적으로 지지되었다. 검증 결과 서비스 공정성은 고객만족과 관계품질에 모두 유의한 영향을 미치는 것으로 나타났으나, 분배공정성은 관계품질에 유의한 영향을 미치지 않는 것으로 나타났다.

비구조적 미지 시스템을 위한 라구에르 네트워크의 적응력 근사화

김윤상,오현철,안두수 成均館大學校 科學技術硏究所 1998 論文集 Vol.49 No.1

This paper presents an efficient method which can approximate the systems with unstructured dynamics using Laguerre networks. The proposed method is to approximate a unstuctured unknown systems adaptively from only input-output information, which can exclude additional procedure for system identification and thus reduce the required computational burden for real-time approximation. Higher convergence speed is achieved with our manner.

관상동맥 스텐트 시술 후의 재협착에 관한 연구

김윤철,이정우,김보영,강정아,임대승,이민수,김정희,성보영,최성준,성인환,전은석 충남대학교 의과대학 지역사회의학연구소 2000 충남의대잡지 Vol.27 No.1

Coronary stent implacement is known as an effective treatment in the intimal dissection after percutaneous transluminal coronary angioplasty and the prevention of restenosis. However, In-stent restenosis still remains a major concern in clinical stenting. The stents were placed in 103 patients from July 1996 to March 1999 and performed follow-up coronary angiograms in 59(57.3%) patients. To identify the clinical, angiographic and procedurerelated variables 'which predict late restenosis within the stented artery, 59 patients(58.3±9.9, M:F= 41:18) were studied. The clinical characteristics of the patients were stable angina in 23(39.0%), unstable angina in 14(23.7%), acute myocardial infarction in 21(35.6%) and old myocardial infarction in 1(1.7%). Coronary stenting was performed in 1 patient(1.7%) for primary lesion, 50 patients(84.7%) for suboptimal results after PTCA, 6 patients(10.2%) for bail-out procedure, and 2 patients(3.4%) for restenotic lesions. All patients were treated with aspirin and ticlopidinc. The follow-up angiograms were obtained at 7±4 months. The overall in-stent restenosis rate was 27.1%. The coronary angiographic findings were 32 single vessel(54.2%), 19 two vessel(32.2%) and 8 three vessel disease(13.6%). The angiographic morphological characteristics were type A in 33(55.9%), type B in 14(23.7%), type C in 12(20. 3%) cases. Variables of 16 patients with restenosis were compared with those of 43 patients without restenosis. Previously known predictors for in-stent restenosis were multiple stenting, stenting for restenotic lesions, residual stenosis after stenting, stenting for total occlusion lesions, reference diameter, balloon to vessel ratio, acute gain and minimal luminal diameter after procedure, design and characteristics of stents, ostial lesion of aorta, high pressure method for stenting, lesion length, diabetes mellitus, size of artheroma, saphenous vein grafts, ulcerlating lesions and calcified lesions. In this study, Reference diameter before stenting(2.43±0.54mm vs. 2.88±0.65mm, p=0.016) and balloon-to-artery ratio(1.28±0.26 vs. 1.11±0.18, p=0.006) were predictors for in-stent restenosis. 1) The overall in-stent restenosis rate was 27.1%. 2) In the analysis of predictors for in-stent restenosis, there was no significant differences in clinical, angiographic factors between group with restenosis and without restenosis. But, Only reference diameter before stenting and balloon-toartery ratio were predictors of late in-stent restenosis. In conclusion, stenting is effective revascularisation method for selected patients with ischemic heart disease, and to minimize in-stent restenosis rate, stent implanting is achieved in a large vessel on the basis of an artery-to-stnet ration of 1:1, if possible.

일반적인 Lattice 구조의 적응 IIR 필터 설계에 관한 연구

오현철,김윤상,안두수 成均館大學校 科學技術硏究所 1998 論文集 Vol.49 No.2

An adaptive joint-process IIR filter with generalized lattice structure is implemented by modifying the conventional lattice filter and making an adaptive algorithm in a system identification problem. LMS algorithm used to estimate of the error-surface gradient to update the filter coefficient.

황체기 결함의 월경주기를 가진 한국여성의 아침 첫 오줌내 Steroid Glucuronide의 농도 변화

장철수,윤용달 대한임상병리사협회 2001 대한임상병리사회지 Vol.21 No.1

신성고혈압쥐에서 혈관내피층이 Phorbol Ester에 의한 수축에 미치는 영향

정수아,김형,차경훈,전제열,윤평진,염철호,박진,조남수,홍순표 대한순환기학회 2003 Korean Circulation Journal Vol.33 No.11

단독주택지역의 주거환경에 대한 주민만족도에 관한 연구

김철수,임성호,윤병구 계명대학교 산업기술연구소 1998 産業技術硏究所 論文報告集 Vol.21 No.1

The main purpose of this study is to suggest some policy directions for a better residential environment in detached housing area in case of Taegu metropolitan city. In order to consider the change of urban spatial structure, study areas are classified into three zone-CBD, inner zone and outer zone. A field survey is conducted to measure residential satisfaction levels in term of safety, health and convenience. The main findings of this research can be summarized as follows. In general, the level of residential satisfaction at CBD is the worst with the lowest levels of the all three measures, while that of outer zone is the best with some dificiencies in term of health. The major determinants of the levels of residential satisfaction are found out to be (i) privacy protection, public transport, air quality and neighborhood facilities in case of CBD, (ii) cleanliness, fire protection, sunlighting and shopping facilities in case of inner zone, and (iii) public transport in case of outer zone. As is discussed, zonal problem is unique.

광중합형 글라스 아이오노머 시멘트의 개발에 관한 연구

김철위,윤수한,임범순 대한치과기재학회 1998 대한치과재료학회지 Vol.25 No.1

The object of this study was to synthesize the experimental light-activated glass ionomer cement change of glass components such as aluminum, fluorine, calcium, and strontium. To reinforce the glass ionomer cement, additions of metallic powder, ceramic powder, and light-activated composite resin to glass ionomer cements were performed. Radiopacity, comprehensive strength, bond strength, fracture toughness, sloubility, and cytotoxicity of the various experimental glass ionomer cements were investigated. From the experiment, the following results were obtained: 1. Experimental light-activated glass ionomer cement showed similar physical and mechanical properties to commercial glass ionomer cement. Radiopacity, resistance of solubility, fracture thoughness, and compressive strength of the experimental cement were superior to those of commercial cements, but bond strength and biocompatibility of the experimental cement were inferior to commercial cements. 2. Addition of amalgam powder to light-activated glass ionomer cement resulted in the lower compressive strength and fracture toughness, but addition of aluminium powder resulted in the enhanced the fracture toughness. 3. Addition of alumina powder (Al₂O₃) could enhance the compressive strength and fracture toughness of the glass ionomer cement without sacrificing of the esthetic property. 4. Physical mixing light-activated glass ionomer cement with light-activated composite resin could enhanced the physical properties except for bond strength.

STWS를 이용한 최적추종 제어기 설계

吳顯哲,金潤相,安斗守 성균관대학교 1998 학술회의지원논문목록집 Vol.1998 No.-

This paper presents a design method of optimal tracking controller and reduced-order obsercer for time invariant comtinuous system using STWS(single term Walsh series). In optimal control, it is well known that the design problem with quadratic performance criteria often involves the determination of time varying feedback gain matrix by solving the matrix nonlinear Riccati equation and of command signal by solving the intergral equation, which makes design procedure quite difficult. Therefore, in order to resolve this problem this paper introduces STWS. In this paper, the time-varying feedback gains and command signals are determined by piecewise constant gains which can be easily determined by algebraic equation using STWS.