http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
조창민(Chang-Min Cho),김승철(Seung-Chul Kim),정성종(Sung-Chong Chung) 한국생산제조학회 2010 한국공작기계학회 추계학술대회논문집 Vol.2010 No.-
Ripple force deteriorates tracking accuracy and generates oscillation in linear motor driven servos. It has periodic relationship with the position of the translator and the magnets. In this paper, a composite controller composed of the PID and feedforward controllers, and the ripple compensator. To derive an accurate dynamic model of the linear servo, system identification of the linear servo with ripple forces is conducted first. The feedforward control consists of velocity and acceleration compensation terms to improve tracking performance. Harmonic modeling of ripple forces is applied to construct the ripple compensator. After selection of optimal gains of the composite controller, linear and sinusoidal motion commands are applied to verify the tracking performance of the linear servo. Experimental results confirm the effectiveness of the developed control system.
위아전절제술 후 발생한 역행성 공장 - 위중첩증 1 예
조창민(Chang Min Cho),하승수(Seung Su Ha),박재홍(Jae Hong Park),김태석(Tae Seok Kim),강천일(Chun Il Kang),이현정(Hyun Jung Lee),김현수(Hyun Soo Kim),탁원영(Won Young Tak),권영오(Young Oh Kweon),김성국(Sung Kook Kim),최용환(Yong Hwan 대한소화기학회 2001 대한소화기학회지 Vol.37 No.6
Retrograde jejunogastric intussusception is a segmental invagination of jejunal loop into stomach through stoma. It is a rare complication which can develop after partial gastrectomy, gastroenteroanastomosis, or enteroanastomosis. Clinical manifestations are abdominal pain, vomiting with bile or blood, and palpable mass in epigastric area. It presents considerable difficulties in diagnosis unless the index of suspicion is high. Endoscopy and upper gastrointestinal series are very helpful in the diagnosis of this disease. Although its management is usually surgical, an endoscopic reduction can alternatively be attempted. When anatomical reduction is performed on appropriate time, the prognosis is fairly good. We report a case of retrograde jejunogastric intussusception developed in a 52-year-old man with a brief review of literature. He had received subtotal gastrectomy and gastrojejunostomy for duodenal ulcer perforation 20 years before. (Korean J Gastroenterol 2001;37:466-469)
조창민 ( Chang Min Cho ) 대한췌담도학회 2017 대한췌담도학회지 Vol.22 No.3
영상 기기의 발달과 건강검진의 보편화로 무증상 담관 확장을 임상에서 흔히 접하게 되는데, 담관 확장만으로는 정상과 비정상을 구분하기는 어렵다. 담관 확장이 의심되는 환자를 진료할 때, 주의해야 할 것은 영상학적 검사 한 가지만으로 판단해서는 안되며, 동반되는 증상이나 간기능 검사를 포함하여 종합적으로 판단하여 접근하여야 한다. 동일한 담관 직경이 있다고 하더라도 연령, 증상 유무, 담낭절제술 유무에 따라 정상 혹은 비정상일 수 있다. 일반적으로 복부 초음파를 통한 담관의 정상범위는 7-8 mm 미만이며, 조영 검사는 10 mm 미만이나, 고령에서는 각각 10 mm와 12 mm까지도 정상일 수 있다. 복부 초음파에서 담관 확장이 발견되었으나 뚜렷한 원인을 발견할 수 없었던 환자에서 담도성 동통이나 간기능 검사의 이상소견이 동반되어 있을 때는 원인질환을 찾기 위해 적극적인 추가 검사를 하는 것이 필요하다. 반면에, 담낭확장이 우연히 발견되고 증상이나 간기능 검사의 이상소견이 없을 때는 추가 검사를 통해서도 상대적으로 원인질환을 발견할 수 있는 경우가 낮으므로 선택적인 판단이 필요하다. asymptomatic bile duct dilatation was commonly found in clinical practice due to the development of imaging devices and frequent health screening examination, it is sometimes difficult to distinguish between normal and abnormal. In evaluating the cause of bile duct dilatation, comprehensive approach should be accompanied, instead of determining by using any one of imaging modalities. Before diagnosing bile duct dilatation, physiologic changes due to aging and history of biliary operation might be considered. The acceptable range for normal diameter of bile duct is 7-8 mm in transabdominal ultrasonography and less than 10 mm in cholangiography. However, the diameter of bile duct in elderly is acceptable up to 10 mm and 12 mm, respectively. Among patients with incidentally found bile duct dilation, further additional image studies are required to confirm the cause of bile duct dilatation in case of presence of symptom and abnormal liver function test. Meanwhile, the truly asymptomatic patient with normal liver enzyme profiles should be followed closely with clinical and laboratory follow-up to help decide whether any additional imaging would be appropriate.
조창민(Chang-Min Cho),임근호(Keun-Ho Lim),정성종(Sung-Chong Chung) 한국생산제조학회 2009 한국공작기계학회 추계학술대회논문집 Vol.2009 No.-
Design is important in the IT, digital appliance, and auto industries. Aesthetic and artistic images have been applied for better quality of the products. 2.5D engraving of glass products is important to fabricate aesthetic patterns in the jewelry industry. Laser and chemical methods have been used to fabricate jewelry. However, heat affection, chemical damage and lack of the 2.5D engraving system have limited the engraving application so far. In this paper, to improve productivity and quality of 2.5D machining on the glass, 2.5D engraving method has been studied through the MBF(Modified Boundary Follower) algorithm and glass machining technique. In addition, to obtain optimum cutting conditions in glass machining for jewelry, micro ball end-milling processes with crack free conditions are studied through Taguchi method. Performance of the developed system is verified through case studies.
내시경유두절제술 후 췌장염 예방을 위한 췌관 배액관 삽입
조창민 ( Chang Min Cho ) 대한췌장담도학회 2016 대한췌담도학회지 Vol.21 No.1
Endoscopic papillectomy (EP) has been considered to be a less invasive, alternative therapy to surgery for ampullary adenoma. However, complication rates after EP could not be ignored, when compared to endoscopic resection for gastrointestinal lesions. Among them, the prevalence of postpapillectomy pancreatitis is higher in EP than ERCP. The prophylactic placement of a pancreatic stent has been reported to decrease the risk of pancreatitis after EP. However, since pancreatic stent placement after EP is not always successful, various novel techniques have been developed to ensure reliable stent placement. Despite the recent advances in EP, a prospective, randomized, controlled study with a larger number of patients is needed to assess the efficacy of pancreatic stent placement to prevent pancreatitis.
김민성(Min-Sung Kim),박찬익(Chan-Yik Park),조창민(Chang-Min Cho),윤종호(Jong-Ho Yoon) 한국항공우주학회 2014 韓國航空宇宙學會誌 Vol.42 No.7
본 논문에서는 스마트 스킨 시제품을 항공기에 장착하고 비행데모시험을 수행하는 절차와 시험결과를 제시하였다. 통신항법용 4개의 안테나를 한 개의 안테나 내장 스킨구조(CLAS)에 삽입하였다. 대수주기 패치형 안테나를 4개의 안테나 주파수 대역을 포함하도록 다중대역 안테나로 설계하였다. 항공기에 장착하기 전에 안테나 내장 스킨구조의 요구조건은 지상시험으로 입증하였다. CLAS 스피드브레이크를 KT-1 항공기에 장착하고 2개 이상의 안테나를 작동시키는 다중 안테나 시험을 지상에서 수행하였다. 항공기에 장착된 기존 장비들과 CLAS와의 호환성을 확인하기 위해 전자파 적합성시험을 수행하였다. 비행데모시험은 4개의 안테나에 대하여 각 1회의 비행을 수행하였다. 비행 중 안테나 통신항법신호의 작동상태와 지속성, 항공기 원형 비행 시 사각지대 유무 확인을 하였다. 안테나 내장 스킨구조의 안테나는 4회 비행데모시험 동안 기대 이상의 성능을 보여주었다. This paper suggests an installation procedure of a smart skin prototype into an aircraft, flight demonstration test procedures and test results. Four communication and navigation antennas are embedded into one Conformal Load-bearing Antenna Structure(CLAS). Log periodic patch type antenna was designed as a multi-band antenna to cover four antenna frequency bands. The requirements of CLAS were verified by ground tests before aircraft installation. A CLAS speed-brake was installed into KT-1 aircraft and performances of dual antennas were verified as multi-antenna tests on the ground. Electromagnetic compatibility tests were conducted to check compatibility between the CLAS and all existing equipments. Flight demonstration tests were conducted by one sortie of flight test for one antenna. The activeness and continuity of communication and navigation signal during the flight, null area of antenna signal along the circling flight were monitored. The embedded antennas worked better than expected during four sorties of flight tests.
통신 항법용 다중대역 안테나 내장 스킨구조의 지상시험평가
김민성(Min-Sung Kim),박찬익(Chan-Yik Park),조창민(Chang-Min Cho),전승문(Seung-Moon Jun) 한국항공우주학회 2013 韓國航空宇宙學會誌 Vol.41 No.11
본 논문에서는 전투기 주구조물에 적용할 수 있는 안테나 내장 스킨구조(CLAS)의 새로운 시험평가 절차를 제시하였다. 대수 주기 패치형 안테나를 통신항법용 다중대역 안테나로 설계하였다. 탄소/유리 섬유 강화 적층 복합재(CFRP/GFRP)를 공력하중을 지지하기 위한 구조로 사용하고 안테나 성능 향상을 위해 하니컴 층을 적층하였다. 여러 재질로 구성된 다층구조의 안테나 내장 스킨구조를 고온의 오븐에서 경화하였다. 내장된 안테나의 이득, 전압 정재파비, 방사패턴을 0.15㎓∼2㎓ 주파수 범위에서 무반향 챔버시설을 이용하여 측정하였다. 안테나 내장 스킨구조의 구조강도를 평가하기 위하여 인장, 전단, 피로, 충격 하중을 부가하는 구조시험을 수행하였다. 각각의 구조시험 후에 안테나 성능시험을 수행하여 초기 값과 비교하므로써 구조시험이 안테나에 미치는 영향을 확인하였다. 새로 개발한 안테나 내장 스킨구조 시험평가 절차를 통신항법용 CLAS에 적용하여 설계개선이 필요한 점을 발견하였다. This paper suggests a test and evaluation procedure of conformal load-bearing antenna structure(CLAS) for high speed military jet application. A log periodic patch type antenna was designed for multi-band communication and navigation antenna. Carbon/Glass fiber reinforced polymer was used as a structure supporting aerodynamic loads and honeycomb layer was used to improve antenna performance. Multi-layers were stacked and cured in a hot temperature oven. Gain, VSWR and polarization pattern of CLAS were measured using anechoic chamber within 0.15~2.0 ㎓ frequency range. Tension, shear, fatigue and impact load test were performed to evaluate structural strength of CLAS. Antenna performance test after every structural strength test was conducted to check the effect of structural test to antenna performance. After the application of new test and evaluation procedure to validate a new CLAS, a design improvement was found.