저장신뢰도 유지를 위한 최적 2단계 주기적 검사정책

조용석,이주호,Cho, Yong-Suk,Lee, Joo-Ho 한국통계학회 2008 Communications for statistical applications and me Vol.15 No.3

본 연구에서는 장기간 보관 중인 장비의 신뢰도를 유지하기 위한 2단계 주기적 검사모형을 제안하였다. 제안된 모형은 불완전한 간이검사와 완전한 정밀검사를 단계적으로 사용하여 고장이 발견되거나 검사 후 저장신뢰도가 미리 정해진 값 이하로 떨어질 때 장비에 대한 오버홀을 수행한다. 제안된 모형을 사용하여 오버홀까지의 단위시간당 기대비용을 유도하고 이를 최소화하기 위한 절차를 구하였으며, 고장시간이 지수분포 및 와이블분포를 따를 경우 제안된 모형을 1단계 주기적 검사모형과 비용함수의 다양한 모수값에 대하여 비교하였다. 또한 실제 운용 중인 유도탄 시스템에 제안된 검사정책을 적용하여 현재 사용 중인 검사정책과의 비교를 수행하였다. In this thesis we propose a two-stage periodic inspection model for maintaining the reliability of a system in long-term storage. There are two types of tests available; a fallible test and an error-free test. The system is overhauled at detection of failure or when the storage reliability after inspection becomes less than or equal to the prespecified value. The expected cost per unit time until overhaul is derived and a procedure for minimizing the expected cost is suggested. The two-stage periodic inspection model is compared with the one-stage periodic inspection model for various parameters of the cost function when the failure time follows exponential and Weibull distributions. The proposed model is then applied to an existing missile system for comparison with the current inspection policy.

Mo 함유 오스테나이트계 스테인리스강의 공식특성에 미치는 이온질화의 영향

조용석,최한철,김관휴 ( Yong Seok Cho,Han Cheol Choe,Kwan Hyu Kim ) 한국부식방식학회 1994 Corrosion Science and Technology Vol.23 No.1

백서 두개골에서 이종골 이식 후 치유에 관한 실험적 연구

조용석,김경원,Cho, Yong-Seok,Kim, Kyoung-Won 대한악안면성형재건외과학회 1999 Maxillofacial Plastic Reconstructive Surgery Vol.21 No.1

The purpose of this investigation was to evaluate the acceptability of the collagen-based xenograft ($Laddec^{(R)}$). Full thickness bone defects were prepared in the calvaria of the rats. In the experimental groups the bone defects were filled with a kind of collagen based xenograft. And bone defects, which left without filling, were used as control groups. Sequential sacrifice was performed at the 1st, 2nd, 4th, 8th, and 16th weeks of experiment. 1. At the 1st week of experiment, infiltration of chronic inflammatory cell was observed in all groups. In the experimental group, resorption of the xenograft was initiated. 2. At the 2nd week of experiment, infiltration of chronic inflammatory cells was decreased in all groups. In the experimental group, active resorption of xenograft and new bone formation from the periphery of the xenograft was observed. 3. At the 4th and 8th weeks of experiment, more resorption of the xenograft and new bone formation with calcification was observed in the experimental group. 4. At the 16th week of experiment, small bone trabecula was formed partially in the control group but that couldn't fill the whole bone defect. In the experimental group, more advanced resorption of xenograft and more new bone formation was observed. However mid portion of the xenograft was still remained without resorption. 5. From this experiment, we concluded that the collagen-based xenograft had some osteoconductive but no osteoinductive property. So the xenograft would be used for the bone defect filling material where rapid bone remodeling is not required.

갑상설관낭종 및 동의 임상적 고찰

조용석(Yong Suk Cho),박성길(Sung Gil Park),전성은(Seong Eun Chon),윤대근(Dae Kun Yoon),정봉화(Bong Wha Chung),허준(Jun Hur),조마해(Ma Hae Cho),조지웅(Ji Woong Cho),박윤규(Yoon Kyu Park),채승완(Seoung Wan Chae),조성진(Seong Jin Cho) 대한외과학회 2003 Annals of Surgical Treatment and Research(ASRT) Vol.64 No.3

H.261의 오류정정 복호기 설계

조용석(Cho yongsuk),정학진(Chong hakjin) 한국통신학회 1994 한국통신학회 학술대회논문집 Vol.1994 No.11

[가솔린엔진부문] 냉시동시 미연 배기가스 점화 기술이 촉매 온도 상승 및 분포에 미치는 영향

조용석(Yongseok Cho),엄인용(Inyong Ohm),김인탁(Intak Kim),김충식(Choongsik Kim),최진욱(Jinwook Choi),천준영(Junyoung Chun) 한국자동차공학회 2000 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

To make close-coupled catalytic converter (CCC) reach light-off temperature within a few seconds after cold-start, UEGI technology was developed to warm up the CCC. The unburned exhaust mixture is ignited by four glow plugs installed upstream of the catalyst. To verify the temperature rise effect by UEGI technology, CCC temperature distribution was measured with thermocouples. The results con finned that UEGI system makes easier for CCC to reach light-off temperature and shortens light-off time. The results also showed that UEGI system doesn't affect CCC temperature distribution so much, but the shape of exhaust manifold strongly affects the temperature distribution.

[가솔린엔진부문] 냉시동시 미연 배기가스 점화 기술을 이용한 배기저감

조용석(Yongseok Cho),김충식(Choongsik Kim),최진욱(Jinwook Choi),천준영(Junyoung Chun),김인탁(Intak Kim) 한국자동차공학회 2000 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

To alleviate the problems of air pollution caused by vehicles, many researchers are trying to develop new emission reduction technologies. In this study, UEGI technology was developed to help three way catalyst's fast light-off. A HC adsorber was applied to UEGI system to improve emission reduction perfo그ance of the system. Experimental results showed that closed-coupled catalyst's light-off time and HC and CO emissions are significantly more reduced by UEGI technology with the HC adsorber. There were 50.8% reduction of THC and 94.4% reduction of CO by the UEGI system, and 78.1% of THC and 96.6% of CO were reduced by the UEGI system with the HC adsorber

루터와 오스만 투르크

조용석(Yong-Seuck Cho) 장로회신학대학교 기독교사상과 문화연구원 2017 장신논단 Vol.49 No.4

본 연구는 16세기 종교개혁시기 오스만 투르크의 유럽침공과 관련된 루터의 신학적 대응을 탐구하고자 한다. 루터는 오스만 투르크의 군사적 위협을 독일민족 혹은 타락한 로마-가톨릭 교회를 위한 하나님의 징계라고 해석한다. 루터는 그의 문건 “투르크 전쟁에 대하여”에서 투르크 보다 적그리스도로서 묘사되는 교황에 대해 좀 더 비판적인 입장을 피력하고 있다. 그러나 이는 세속정부가 외부의 공격을 방어하지 않아도 된다는 사실을 의미하지 않는다. 이와 같은 신학적 신념에 근거하여, 루터는 그리스도인들에게 회개와 기도를 통하여 오스만 투르크에 대항해야 한다고 영적인 차원에서 권면한다. 여기서 회개는 오스만 투르크와의 영적인 전쟁의 수행을 위한 출발점이 된다. 요약하자면, 루터는 소위 그의 두 왕국론에 근거하여 영적 정부와 세속 정부의 통치영역을 구분했다. 즉 황제는 전쟁과 같은 세속적인 사안을 다루어야 하며, 성직자는 그리스도인들에게 경건한 행위를 통하여 싸워야 한다고 주장했던 것이다. 1529년 오스만 투르크가 비엔나를 침공했을 때, 루터는 오스만 투르크의 군사적 위협을 종말론적 전망 속에서 고찰했다. 그는 묵시적 종말론의 전망 속에서 오스만 투르크의 침공이 다니엘서 7장에 이미 예언되었다고 확신했다. 그는 성서에 근거하여 오스만 투르크가 결코 유럽의 기독교를 파멸시킬 수 없을 것이라고 생각했다. 더 나아가 그는 (이슬람 교도들을 위한) 올바른 기독교 변증을 위하여 코란을 연구함으로써, 이슬람 종교를 객관적으로 파악할 수 있는 기회를 확보했다. 이를 통하여 그는 독일 그리스도인들이 신앙을 강화할 수 있으며, 기독교의 진리의 명백한 증거를 제시할 수 있을 것이라고 확신했다. This study aims to investigate Luther’s theological reaction to the Ottoman invasion of Europe at the time of the Protestant reformation. Luther made it clear that sinful Germans or the corrupt Roman Catholic church had earned God’s punishment and that the Turks could be a divine means to carry it out, even if the Turks were demonic pawns. In On War against the Turk, Luther is actually less critical of the Turks than he is of the Pope, whom he calls an anti-Christ. However, this did not mean that the earthly authority should not defend their land from an aggressive attack and had the obligation to do so. From this conviction, Luther gave spiritual counsel to European Christians, providing the exhortation that they must fight against the Turk with repentance and prayer. Repentance must be the starting point. To sum up, Luther explained that the spiritual and earthly authorities act for their divinely-ordained purpose on the basis of the so-called Luther’s two kingdoms doctrine. It should be noted that the emperor must deal with secular matters like war and clergy must exhort Christians to fight as acts of piety. About the time of the siege of Vienna in 1529, Luther also began to view the Turkish threat in apocalyptic perspective. He was convinced that the rise of the Turks was foretold in the eschatological prophecies in scripture, especially Daniel 7. From the prophecy of Daniel 7, Luther concluded this determined reality that shaped his entire perspective on the Turks: The Turks would never conquer European Christianity. Furthermore, The study Quran afforded him the opportunity finally to engage Islam at its source. By exposing the errors of the Quran, Luther was convinced that German Christians would find their faith strengthened and could begin to offer the obvious evidence for the truth of the Christian religion. It is this correct purpose of Luther’s apologetic.

난류연소장치를 이용한 스파크 점화 화염의 성장에 관한 연구-스파크 출력의 영향

조용석(Y.S.Cho) 한국자동차공학회 1995 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1995 No.11_2

An experimental study to evaluate the effect of spark power on the growth rate of spark-ignited flame kernels was conducted in an optically-accessible turbulent flow combustion system at latm, 300K conditions. All measurements were made with premixed, propane-air at a fuel/air equivalence ratio of 0.93. Two flow conditions were studied: a low turbulence intensity case and a high turbulence intensity case. The growth of the spark-ignited flame kernel was recorded over a time interval from 83μsec to 20msec following the start of ignition using high speed laser shadowgraphy. In order to evaluate the effect of spark power, tests were conducted with a long duration (-4msec) inductive discharge ignition system with an average spark power of 14 watts and two short duration (∼100nsec) breakdown ignition systems with average spark powers of<br/> 6×10⁴ and 6×10^5 watts.<br/>

NO₂LIF를 이용한 공연비 측정

조용석(Y.S.Cho) 한국자동차공학회 1996 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1996 No.6_2

The results show that fluctuations in local mixture strength due to incomplete fuel-air mixing cause flame kernel surfaces to become wrinkled and distorted. Incomplete fuel-air mixing was also found to result in a significant increase in "cyclic" variations in the flame kernel growth. The average flame kernel growth rates for the premixed and the incompletely mixed cases were found to be within the experimental uncertainty except for the 33%-RMS-fluctuation case where the growth rate is significantly lower. The premixed and 6%-RMS-fluctuation cases had a 0% misfire rate. The misfire rates were 1% and 2% for the 13%-RMS-fluctuation and 24o%-RMS-fluctuation cases, respectively; however, it drastically increased to 23% in the 33%-RMS-fluctuation case.<br/>