모터내장형 주축의 동특성 해석

조정준,김석일,최대봉 한국정밀공학회 1993 한국정밀공학회 학술발표대회 논문집 Vol.1993 No.11월

공작기계용 고속주축계의 동특성해석

조정준,김석일,최대봉 한국정밀공학회 1993 한국정밀공학회 학술발표대회 논문집 Vol.1993 No.5월

선반용 고속주축계의 동특성 해석

조정준,김석일,최대봉 한국정밀공학회 1994 한국정밀공학회지 Vol. No.

고속절삭을 통해서 가공능률과 가공정밀도의 향상을 도모할 수 있기 때문에, 최근에는 공작기계용 고속주축계가 많은 주목을 받고 있다. 본 연구에서는 주축 선단부에 무거운 척과 공작물이 위치하는 선반용 고속주축계의 동특성을 해석하기 위해서 유한요소법을 도입하였다. 특히 세장비가 비교적 작은 주축은 Timoshenko 이론으로, 폭이 유한한 베어링은 반경방향 외에도 모멘트방향의 강성 및 감쇠특성을 가지고 있는 것으로 모델화하였다. 그리고 선반용 고속주축계의 고유진동수와 감쇠비에 대한 주축회전수, 베어링의 지지특성, 베어링의 간격, 주축재료의 내부감쇠율 등의 영향을 고찰하였다.

해부실습에서 동료평가에 대한 의과대학생들의 인식과 필요성

조정준,강성우,이승준,정수정,이재호 대한체질인류학회 2019 해부·생물인류학 (Anat Biol Anthropol) Vol.32 No.3

Peer review in dissection is a good evaluation method that allows students not only to recognize professional behavior of peers, but also to look back on themselves. The purpose of this study is to analyze the recognition and feelings of students about peer review in dissection and to use peer review more effectively. In this study, it was to examine the reflection on grades of peer review, the improvement on attitude of dissection by peer review, and the reliability of peer review, also, additionally necessary subjects, the method of peer review, the emotions of students during the peer review. As a result of the questionnaire survey, the necessity about reflection of peer review (48, 67.6%), the improvement on attitude of dissection (41, 57.7%) and the reliability of peer review (30, 44.1%) were positive. Moreover, many students asked additionally necessary subjects not to be required except for anatomy (42, 67.7%). In the questionnaire on the method of peer review, to select students who have been good and bad in the practice is best (34 students, 57.6%). In the questionnaire for emotions of students during the peer review, “bad” was the most common (25, 39.7%), and the average value was about 2.7 in the 5 scale. There is a limitation to utilize peer review as an evaluation method of anatomy education. Therefore, much more effort is needed to improve the utilization of peer review and the professor should support the emotions of students during the peer review. 해부실습에서 동료평가는 학생들이 자신과 동료들의 행동을 되돌아보게 하는 좋은 평가 방법이다. 본 연구의 목적은 해부실습에서 동료평가에 대한 학생들의 인식과 감정을 분석함으로써 향후 동료평가를 보다 효 과적으로 사용하고자 한다. 본 연구에서는 2018학년도 K대학교 의과대학에 재학 중인 본과 1학년 학생 72명 을 대상으로 동료평가의 성적 반영, 실습 태도의 개선 효과, 평가 신뢰도와 동료평가 시행이 추가적으로 필요 한 과목, 동료평가 방법, 동료평가 시 학생들의 감정에 대한 총 6개 문항을 설문하였다. 설문 조사 결과, 동료평 가의 성적 반영의 필요성 (48명, 67.6%), 실습 태도의 개선 효과 (41명, 57.7%)와 평가의 신뢰도 (30명, 44.1%) 는 긍정적인 반응을 보였다. 그리고 해부학 외 동료평가가 필요한 과목은 없다 (42명, 67.7%)는 의견이 많았다. 평가방법에 대한 설문에서는 해부실습에 성실히 참여한 학생과 성실히 참여하지 않은 학생 모두를 평가하자 는 의견이 가장 많았다 (34명, 57.6%). 그리고 평가 시 감정에 대한 설문에서는 나쁨 (25명, 39.7%)이 가장 많았 으며, 평균값은 5점 척도에서 약 2.7로써 나쁨과 보통 사이였다. 아직 해부학 교육의 평가 방법으로 동료평가를 활용하는 데에는 많은 한계가 있기 때문에 동료평가의 활용도를 높이기 위해서는 평가 시 학생들의 감정을 잘 조절할 수 있도록 많은 노력이 필요하다.

True Aneurysm of the Common Coronary Button in a Marfan Patient with an Anomalous Right Coronary Artery after a Bentall Procedure: A Case Report

조정준,김윤석,김근직,김재현 대한심장혈관흉부외과학회 2022 Journal of Chest Surgery (J Chest Surg) Vol.55 No.3

True aneurysms of the coronary artery after aortic root replacement in Marfan syndrome patients are very rare. An anomalous origin of the right coronary artery (RCA) from the left sinus of Valsalva adds complexity during aortic root surgery. We present a case of a 37-year-old male patient with Marfan syndrome who had an RCA anomaly and a 4.5-cm true aneurysm of the common coronary button 14 years after a previous Bentall procedure. A redo Bentall operation and hemi-arch replacement were successfully performed. The anomalous origin of the RCA from the left sinus of Valsalva was safely divided and anastomosed as separate coronary buttons to the prosthetic composite valve graft. To prevent coronary button aneurysms after aortic root surgery in Marfan patients, the coronary buttons and the corresponding side holes on the prosthetic graft must be reduced to the maximum possible extent.

스페인 바르셀로나 동물원 방문기

조정준,Jo, Jeong-Jun 대한수의사회 2013 대한수의사회지 Vol.49 No.10

한국 대중문화의 ‘다음’을 그린다

조정준 영화진흥위원회 2012 현안보고(이슈페이퍼) Vol.- No.-

일본 도쿄, 오사까, 고베 Pet Shop 방문기

조정준,Jo, Jeong-Jun 대한수의사회 2013 대한수의사회지 Vol.49 No.12

더러브렛 말의 Streptococcus equi subsp. zooepidemicus 감염에 의한 복막염

조정준,강상철,양형석,양재혁,손원근,배종희,김재훈,Cho, Jung-Joon,Kang, Sang-Chul,Yang, Hyoung-Seok,Yang, Jae-Hyuk,Son, Won-Geun,Bae, Jong-Hee,Kim, Jae-Hoon 대한수의학회 2007 大韓獸醫學會誌 Vol.47 No.3

Fibrinopurulent peritonitis and abdominal abscesses associated with Streptococcus (S.) equi subsp. zooepidemicus is reported in a 1-year-old female thoroughbred horse. The horse died after showing 5-day history of the cold, severe abdominal distention, abdominal breathing, hyperthermia, anorexia, and loss of intestinal sound. At necropsy, several liters of turbid yellowish green fluid were seen in the abdominal cavity. Yellowish creamy and fibrinous or bloody materials were presented on the serosa of various abdominal organs that were intensively adhered with each other. Spleen and mesenteric lymph node were remarkably enlarged. Affected lobes of the lung showed severe congestion, hemorrhage and doughy consistency. Histologically, the lung showed hemorrhagic pneumonia with diffuse congestion and edema. Severe diffuse fibrinopurulent peritonitis with Gram-positive bacterial cocci and adjacent fibrosis were showed in the serosa of various abdominal organs such as liver, spleen, stomach, and intestine. And multifocal abscess pouches were presented in the granulation tissue of abdominal viscera. S. equi subsp. zooepidemicus was isolated from the peritoneal swab, abdominal organs, and lung. Hematogenous dissemination of bacteria from hemorrhagic pneumonia is proposed as the route of infection in this case.

터널 경계부 휘도수준에 따른 운전자 연령대별 안전수준 비교

조원범,정준화,김도경,박원일 한국도로학회 2015 한국도로학회논문집 Vol.17 No.1

PURPOSES : The purpose of this study is to suggest a basis for setting appropriate safety goals specifically related to the threshold zone luminance in a vehicular traffic tunnel. . METHODS: In the test, drivers were divided into two groups. One group consisted of all drivers (average drivers) group with an age ratio of drivers holding domestic driver's license and driver group by age to produce threshold zone luminance in the tunnel. The threshold zone luminance produced as a result was used to analyze how it affects the safety level of each driver group and provide a basis for setting an appropriate safety criterion that can be used to determine threshold zone luminance. We used test equipment, test conditions, and ananalysis of threshold zone luminance identical to that reported by ChoandJung(2014) but the values of adaptation luminance in our analys is were expanded to range from100 to10,000 cd/m2. RESULTS : Adaptation luminance and threshold zone luminance are found to be related by a quadratic function. The threshold zone luminance needed by older drivers to ensure a certain safety level is significantly higher than that for drivers of other age brackets when adaptation luminance increases. 56% of older drivers are at an increased risk of an accident at the same luminance for which the safety level of average drivers is 75%. The safety level that can be achieved for older drivers increases to above 60% when threshold zone luminance level is set with the goal of attaining a safety level of more than 85% for average drivers. The safety level that can be attained for average drivers is above 90% when the threshold zone luminance is high enough to ensure over 75% in the safety level of older drivers. Results of this study are applicable to highways and others whose designed speed is 100 km/h. CONCLUSIONS : Threshold zone luminance determined on the basis of drivers having average visual ability is of limited value as a performance standard for ensuring the safety of older drivers. Hence, safety level for older drivers should be considered separately from safety levels for drivers with an average ability to avoid risk. Upward adjustment of older drivers' safety level in the process of determining appropriate threshold zone luminance in a vehicular traffic tunnel may bring both tangible and intangible benefit as a result of reducing accidents. However, there is an associated dollar cost arising from installing and operating lights. As a result, the economic impact of these trade-offs should also be considered.