소프트웨어 신뢰도 측정 지원 도구의 설계 및 구현에 관한 연구

문철이(Chul-Yi Moon),김원중(Won-Joong Kim),지동해(Dong-Hae Chi) 한국정보과학회 1991 한국정보과학회 학술발표논문집 Vol.18 No.2

신뢰성있는 소프트웨어를 경제적으로 개발하기 위하여 많은 소프트웨어 신뢰도 모델이 개발되어 왔다. 그러나 신뢰도 모델을 실제의 개발 과정에 적용하기에는 개발 환경에 맞는 신뢰도 모델의 선택, 신뢰도 측정을 위한 고장 자료의 수집 방법, 신뢰도 측정 지원 도구의 부족등과 같은 문제점들이 남아있다. 본 논문에서는 이러한 문제점들을 해결하기 위하여 시험 사례의 수행과 고장 자료의 수집과정을 자동화하여 신뢰도 모델에 부합하는 양질의 고장 자료를 시험과 동시에 실시간으로 수집하고 이를 이용하여 신뢰도를 측정하는 신뢰도 측정 지원 도구에 대하여 기술한다. 그리고 이를 운영체제 개발 과정에 적용한 사례를 소개한다. 신뢰도 측정 지원 도구의 사용으로 신뢰도 측정 자료를 개발 과정에서 실시간으로 수집하고 처리함으로써, 개발중인 소프트웨어의 신뢰도를 끊임없이 관찰하고 그 결과를 개발 과정에 반영하여 신뢰성이 높은 소프트웨어를 경제적으로 개발하는데 도움을 줄 수 있도록 하였다.

고속영상처리에 의한 레일형상측정시스템 개발

문철이(Moon Chul Yi),김만철(Kim Man Chul) 한국철도학회 2006 한국철도학회 학술발표대회논문집 Vol.- No.-

Railway track supports and guides train and it directly affects ride quality and safety. To maintain track quality, regular maintenance activity is essential but it degrades track usage since maintenance activity occupies the track during the work. To achieve maximum track efficiency, track inspection should be performed at commercial running speed. In this paper, we designed and developed high speed rail profile measurement system using laser light sectioning method with line laser generator, digital camera and DSP based image processing system. The measurement system can supports rail profile measurement at the speed of 300 Km/h that can be applied to KTX.

3D 레이저 스캐너 기반의 터널스캐너 개발

사공명,문철이,이준석,황선근,김병홍,SaGong, Myung,Moon, Chul-Yi,Lee, Jun-S.,Hwang, Seon-Keun,Kim, Byung-Hong 한국터널지하공간학회 2006 한국터널지하공간학회논문집 Vol.8 No.4

구조물은 시공과 더불어 노화 현상이 발생하는데 해당 구조물의 효율적인 사용을 위해서는 주기적인 점검 및 유지보수가 수행되어야 한다. 적절한 유지보수의 시기 및 방법의 결정에 있어서는 사전 점검이 중요한 역할을 한다. 본 연구에서는 터널의 사전점검 자동화를 위한 검측 시스템의 개발을 목표로 하고 있으며 이를 위한 사전단계로 시작품을 제작하였다. 시작품 제작에 앞서 기존의 영상 및 레이저를 기반으로 하는 터널 스캐너를 비교 분석하였으며 초기 단계의 터널 스캐너 시작품을 제작하였다. 레이저 스캐닝 시스템 제작에 앞서 범용의 근거리 측량용 상용 레이저 스캐너를 통하여 레이저 스캐너의 적용성을 확인하였으며 그 결과로부터 레이저 스캐너를 바탕으로 하는 터널 스캐닝 시스템이 제작되었다. 제작된 시스템을 바탕으로 실제 공용중인 여러 형상 및 크기의 터널에 대한 스캐닝이 수행되어 장비의 검증이 이루어 졌다. Most structures experience deterioration after construction. A routine inspection and maintenance must be accomplished for the efficient use of the structures. The routine inspection will play a major role on the determination of maintenance period and method. This study aims development of an automated tunnel inspection system based upon a 3 dimensional laser scanner. As for the initial stage of the project, a prototype tunnel scanner has been developed. The development of a tunnel scanner prototype follows comparison between image scanning and laser scanning system and investigation on the applicability and adaptivity of the scanners to the railway tunnel scanner. The applicability of the laser scanner on the railway tunnel has been confirmed from the pilot test by using commercialized general purpose close range laser scanner and applicability of a laser scanner as a railway tunnel scanner has been checked. From the result, a prototype of railway tunnel scanner has been built and the calibration of the system was carried out. Finally the developed tunnel laser scanner has been applied to different shapes and sizes of tunnels in use.

임상연구 : Sevoflurane과 Propofol 마취가 Rocuronium의 깊은 근이완으로부터의 회복기에 미치는 영향

정종성 ( Jong Seong Jeong ),이수현 ( Su Hyun Lee ),전영훈 ( Young Hoon Jeon ),문철원 ( Chul Won Moon ),김시오 ( Si Oh Kim ),백운이 ( Woon Yi Baek ) 대한마취과학회 2003 Korean Journal of Anesthesiology Vol.45 No.4

베어링 편심도와 자세각에 따른 저어널 베어링의 윤활효과

김종도(Jong-Do Kim),왕일군(Yi-Jun Wang),윤문철(Moon-Chul Yoon) 한국기계가공학회 2015 한국기계가공학회지 Vol.14 No.5

The thickness of adsorbed molecular layers is the most critical factor in studying thin-film lubrication, and it is the most essential parameter that distinguishes thin-film from thick-film lubrication analysis. The thin film between the shaft and bearing surface within a very narrow gap was considered. The general Reynolds equation has been derived for calculating thin-film lubrication parameters affecting the performance of the circular journal bearing. Investigation of the load-carrying capacity and pressure distribution for the journal bearing considering the adsorbed layer thickness has been carried out. A Reynolds equation appropriate for the journal bearing is used in this paper for the analysis, and it is discussed using the finite difference method of the central difference scheme. The parameters, such as eccentricity and attitude angle, are used for discussing the load-carrying capacity of the journal bearing. The results reported in this paper should be applied to analysis of the journal bearing with different lubrication factors. The steady-state analysis of the journal bearing is conducted using the Reynolds model under thin-film lubrication conditions. For a journal bearing, several parameters, such as a pressure, load capacity, and pressure components of the bearing can be obtained, and these results can be stored in a sequential data file for later analysis. Finally, their distribution can be displayed and analyzed easily by using the MATLAB GUI technique. The load-carrying capability of the journal bearing is observed for the specified operating conditions. This work could be helpful for the understanding and research of the mechanism of thin-film lubrication.

저어널 베어링의 베어링 인자에 따른 윤활효과분석

김종도(Jong-Do Kim),진도훈(Do-Hun Chin),왕일군(Yi-Jun Wang),곽재섭(Jae-Sub Kwak),윤문철(Moon-Chul Yoon) 한국트라이볼로지학회 2015 한국트라이볼로지학회 학술대회 Vol.2015 No.4

제왕절개술중 정맥마취약제의 투여가 뇌파스펙트럼 분석에 미치는 영향

백운이,김시오,문철원 대한마취과학회 1996 Korean Journal of Anesthesiology Vol.31 No.3

Background: Anesthesia induces the spectral changes in EEG. Attempts to relate these spectral changes to adequacy of anesthesia have been hindered due to the complex waveforms of EEG. The objective of this investigation is to monitor the awareness of patients during cesarean section by means of EEG spectral analysis. Methods: 20 patients for cesarean section aged from 24 to 39 and ASA class I or II, were maintained with O₂(50%)-N₂O(50%)-enflurane(0.8%). And they were administered with midazolam(0.07 mg/kg) in group I(n=6), fentanyl(l ㎍/kg) in group II(n=7), and fentanyl(2 ㎍/kg) in group III(n=7) after birth. The density of each spectral band in EEG (delta 1-3.25 Hz, theta 3.5-7.75 Hz, alpha 8-12.15 Hz and beta 13-31.75Hz) was analyzed to derive total density, delta ratio and median power frequency. Results: The spectral data demonstrated that the alpha rhythm was dominant in pre-induction period and beta rhythm was abundant both in the immediate post-induction period and after birth for all three groupslta ratio and median power frequency decreased after injection of midazolam and fentanyl in all three groups. None of patients could reeall the memory about experience during cesarean section. Conclusions: These findings indicate that EEG spectral analysis is potentially useful to determine the changes of cerebroelectrical activity but difficult to monitor the awareness of patients during cesarean section.

경요도 전립선절제술에서 척추마취 시 소용량 Bupivacaine-Fentanyl의 병용투여와 상용용량 Bupivacaine의 임상 효과 비교

곽경화,이수현,전영훈,문철원,백운이 대한마취과학회 2002 Korean Journal of Anesthesiology Vol.43 No.4

Background: The combination of local anesthetics and opioids in the spinal anesthesia has a synergic analgesic effect, Therefore, we compated intraoperative conditions and clinical effects of low dose (5 mg) bupivacaine added with fentanyl versus a conventional dose(10 mg) of bupivacaine in spinal anesthesia for a transurethral resection of the prostate (TURP). Methods: Forty five ASA class 1 and 2 patients scheduled for a TURP were randomly divided into three groups. Group B (n = 15) received bupivacaine 10 mg, group BF (n = 15) received bupivacaine 5 mg added with fentanyl 20 ㎍, and group BFE received bupivacaine 5 mg added with fentanyl 20 ㎍ and 0.2 mg epinephrine. Blood pressure and heart rate were recorded every 5 minutes before and after spinal anesthesia. Sensory blockade was measured by a pin-prick test and motor blockade was evaluated by the Bromage motor scale. Side effects including pruritus, nausea, vomiting, respiratory depression, and intraoperative pain were observed. Results: The duration of sensory and motor blockade in group BF was significantly shorter than in group B and group BFE (P < 0.05). Without statistical significance, hypotension (6.7%) and bradycardia (13.3%) were observed in group B and pruritus (26.7%) and nausea (13.3%) occurred in all patients who received fentanyl. Conclusions: The addition of fentanyl 20 ㎍ to low dose bupivacaine 5 mg resulted in short lasting motor and sensory block, compared with conventional dose bupivacaine 10 mg. Therefore, we concluded that the clinical application of this method could provide adequate analgesia with early discharge and no serious side effects for TURP patients. (Korean J Anesthesiol 2002; 43: 418~423)