원격조작에 의한 작업대상물 강성과 마찰 특성의 동정

권혁조,전지명,김진옥,문일동,오재윤 전북대학교 공학연구원 ( 구 전북대학교 공업기술연구소 ) 2002 工學硏究 Vol.33 No.-

This study performs a workpiece stiffness and frictional characteristic identification experiments by teleoperation. Experiments are performed using a bilateral force feedback teleoperation system. It is composed of a master manipulator, the slave manipulator equipped with a force/torque sensor, and a real-time control system. To control the teleoperation system, a position-force controller is developed. The slave manipulator is controlled by the master manipulator's position command and the master manipulator is controlled by the force information from the slave manipulator. This study presents a method to find the slave manipulator's stiffness. And, this study presents a method to compute the workpiece stiffness based on the measured pressing force and deflection at the slave manipulator. Also, this study performs a workpiece frictional characteristic identification experiments. In the experiments, the slave manipulator rubs a workpiece with an arbitrary pressing force. While the slave manipulator rubs a workpiece, a vertical force and a frictional force are measured and the ratio of a frictional force to a vertical force is considered as a frictional characteristic.

Revisiting Application of Exercise Electrocardiography in Patients with Stable Ischemic Heart Disease

Jun-Hyok Oh 대한심장학회 2020 Korean Circulation Journal Vol.50 No.5

N

혈구포식 림프조직구증을 동반한 Kikuchi병 1례

오준혁,박주현,황상연,이선희,김성일,김지연,이창훈,정주섭,이은엽,조군제 대한감염학회 2004 감염과 화학요법 Vol.36 No.3

Kikuchi병은 경부 림프절 종대와 발열을 특징으로 하는 양성질환으로, 대부분 수주에서 6개월 이내에 증상의 호전을 보이고, 아직 정립된 효과적인 치료는 없다. 드물게 재발 또는 전신성 홍반성 루푸스와 같은 다른 질환들이 동반되는 경우가 있어 추적 관찰이 필요하다. 특히 혈구포식 림프조직구증(hemophagocytic lymphohistiocytosis)이 Kikuchi병에 동반되어 발생하는 경우에는 매우 드물게 보고되고 있다. 저자들은 발진 및 고열, 경부 종괴를 주소로 내원한 35세 여자환자에서 경부 림프절 조직 검사를 시행하였고, 조직검사에서 괴사성 림프절염 소견이 관찰되어 Kikuchi병을 진단하였다. 스테로이드 강압요법 및 대중적 치료하였으나 환자의 증상이 악화되었고, 일반 혈액 검사에서 범혈구 감소 및 혈청 ferritin이 증가하여 시행한 골수 및 간 조직검사에서 적혈구와 혈소판, 림프구 등을 탐식한 조직구들의 증식이 관찰되었다. Kikuchi병에 동반된 혈구포식 림프조직구증을 진단한 1례를 경험하였기에 문헌고찰과 함께 보고하는 바이다. Kikuchi's disease usually occurs in young women and is characterized by localized lymphadenitis (mostly cervical) usually associated with fever. It is considered a self-limited disease and most patients recover spontaneously within a few weeks to 6 months without any serious sequelae. However, patients with Kikuchi's disease require a systemic survey and regular follow-up for several years because it may be associated with other diseases such as systemic lupus erythematosus. To our knowledge, there are very few reports of Kikuchi's disease accompanied by hemophagocytic lymphohistiocytosis. Biopsy of a right cervical lymph node in a 35-year-old female who presented with fever and masses in the right cervical region showed necrotizing lymphadenitis and a diagnosis of Kikuchi's disease was reached. She was started on methylprednisolone pulse therapy (500 ㎎ for 3 days) but developed generalized rash and fever. Laboratory data showed pancytopenia, elevation of serum transaminase and ferritin levels. Bone marrow and liver biopsy showed proliferation of histiocytes and Kupffer's cells engulfing lymphocytes, platelets and red blood cells, respectively. We report a case of Kikuchi's disease accompanied by hemophagocytic lymphohistiocytosis

무선랜 시스템을 위한 계산이 간단한 초기 동기부 설계

조준범(Jun-Beom Cho),이종협(Jong-Hyup Lee),한진우(Jin_Woo Han),유연상(Yeon-Sang You),오혁준(Hyok-Jun Oh) 대한전자공학회 2012 전자공학회논문지 Vol.49 No.12

주파수 옵셋 보상, 프레임 동기화, Timing Recovery를 포함하는 동기화는 모든 유/무선 통신 시스템에서 가장 중요한 신호 처리 블록이다. 대부분의 통신 시스템에서는 Training sequences 또는 프리앰블을 기반으로하는 동기화 방법이 사용된다. IEEE에서 제정한 802.11a/g/n의 무선랜 표준은 OFDM 시스템을 기반으로 한다. OFDM 시스템은 주파수와 타이밍 동기화 에러에 대해서 싱클캐리어 시스템보다 더 민감한 것으로 알려져 있다. 프레임의 시작점과 OFDM 심볼 및 훈련심볼의 시작점은 상관관계를 이용하여 추정될 수 있다. 상관관계를 처리 기능을 하는 블록은 일반적으로 많은 수의 곱셈기로 인하여 큰 복잡도를 갖게 된다. 본 논문에서는 IEEE 802.11a/g/n 시스템을 위한 훈련심볼 내의 심볼값이 반복되는 특성을 활용한 복잡도가 현저히 낮은 동기화 기법을 제안한다. 시뮬레이션과 구현결과 제안된 기법이 기존의 방법보다 성능저하는 없는 반면 훨씬 적은 복잡도를 갖는 결과를 보여준다. Synchronization including timing recovery, frequency offset compensation, and frame synchronization is most important signal processing block in all wireless/wired communication systems. In most communication systems, synchronization schemes based on training sequences or preambles are used. WLAN standards of 802.11a/g/n released by IEEE are based on OFDM systems. OFDM systems are known to be much more sensitive to frequency and timing synchronization errors than single carrier systems. A loss of orthogonality between the multiplexed subcarriers can result in severe performance degradations. The starting position of the frame and the beginning of the symbol and training symbol can be estimated using correlation methods. Correlation processing functionality is usually complex because of large number of multipliers in implementation especially when the reference signal is non-binary. In this paper, a simple correlation based synchronization scheme is proposed for IEEE 802.11a/g/n systems. Existing property ofa periodicity in the training symbols are exploited. Simulation and implementation results show that the proposed method has much smaller complexity without any performance degradation than the existing schemes.

근위부 상완골 골절의 술 후 하방 아탈구

문준규 ( Jun Gyu Moon ),남혁우 ( Hyok Woo Nam ),김종오 ( Jong Oh Kim ),하종경 ( Jong Kyoung Ha ),유석배 ( Seok Bae Ryu ) 대한골절학회 2005 대한골절학회지 Vol.18 No.1

『침구대성(鍼灸大成)』 의안(醫案)중 이질(痢疾), 간질(癎疾) 등 10안(案)에 대한 연구(硏究)

권오혁 ( Oh Hyeok Kwon ),조학준 ( Hak Jun Jo ),이재혁 ( Jae Hyok Lee ) 대한한의학원전학회 ( 구 대한원전의사학회 ) 2008 대한한의학원전학회지 Vol.21 No.4

We have known that 『Chimgudaeseong(鍼灸大成)』 had been written by Yanggyeju(楊繼洲) in Ming(明) dynasty. And it had been the only text book of acupuncture & moxibustion for 300 years. This book is composed of 10 chapters dealing almost all the medical theories of that times. This book is so enormous that it is hard to understand essential ideas of author. The reading medical records is one of the best way to develop one`s abilities of curing a disease without clinical practice. so we can`t help dealing with medical records, because it is one of important method of understanding Oriental Medicine. On this study, we investigate a objective method on understanding medical records in 『Chimgudaeseong(鍼灸大成)』.

Poster Session:PS 1171 ; Cardiology : Percutaneous Cardiopulmonary Support Experience of a National University Hospital in Busan

( Dong Hun Shin ),( Jun Hyok Oh ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Cardiopulmonary support has been used to treat the patients with refractory cardiogenic shock since 1950s. In advent of portable system its use has been widened considerably. In this retrospective study, we report our single center experience concerning possible indications, complications and outcomes of percutaneous cardiopulmonary support (PCPS) Methods: From January 2013 to March 2014, we searched the patients who were supported by PCPS system by reviewing the medical records in cardiology department at our Hospital. Infectious organism was limited to what was identifi ed within 2 weeks after weaning of PCPS. Results: A total of 9 patients were supported by PCPS with CAPIOX CX® system (Terumo inc. , Tokyo, Japan) initially for STEMI/NSTEMI in 4 patients, myocarditis in 3 patients, valvular heart disease in 1 patient, and acute respiratory distress syndrome (ARDS) in 1 patient. And in 4patients, cardiopulmonary resuscitation was done before PCPS. The mean duration of PCPS support was 79. 1±76. 6 hours and 5 of them were recovered and discharged alive. All the patients needed transfusions of various forms of blood products, especially 3 patients occurred major bleeding. And there was one major stroke and one hyperbilirubinemia in related to PCPS treatment. From blood culture, pathogens were detected in 2 patients. Conclusions: PCPS treatment was a valuable means to treat the patients with cardiovascular collapse, but not without costs. It will need to confi gure the appropriate team for this treatment. Efforts to reduce its associated complications should be made to improve outcomes.

A Study on the Usefulness of Ischemia-modified Albumin (IMA) in the Setting of a Symptom-Limited Exercise Stress Test to Detect Myocardial Ischemia

( Joon Sang Lee ),( Jun Hyok Oh ),( Byung Jae Ahn ),( Seong Ho Kim ),( Moo Young Kim ),( Woo Hyung Bae ),( Hyeon Gook Lee ),( Jun Kim ),( June Hong Kim ),( Kook Jin Chun ),( Taek Jong Hong ),( Yung Wo 대한내과학회 2005 대한내과학회 추계학술대회 Vol.69 No.10

급성 심근경색증에서 관상동맥 중재술시 발생하는 reflow disturbance 현상의 위험인자

안성규 ( Sung Gyu An ),오준혁 ( Jun Hyok Oh ),박태익 ( Tae Ik Park ),이상현 ( Sang Hyun Lee ),장형하 ( Hyung Ha Jang ),이동원 ( Dong Won Lee ),하재경 ( Jae Kyung Ha ),이한철 ( Han Cheol Lee ),김준 ( Jun Kim ),김준홍 ( June Hong K 대한내과학회 2008 대한내과학회지 Vol.74 No.1

목적: Reflow disturbance 현상은 급성 심근경색증으로 관상동맥 중재술을 받는 환자의 예후를 악화시키는 중요한 요인이다. 본 연구는 급성 심근경색증 환자에게 스텐트를 이용한 경피적 관상동맥 중재술을 시행할 경우 reflow disturbance 현상의 발생빈도와 위험인자를 분석하고자 하였다. 방법: 2003년 2월부터 2005년 6월까지 급성 심근경색증으로 부산대학교병원을 방문하여 경피적 관상동맥 중재술을 성공적으로 받은 475명의 환자를 대상으로 연령, 성별, 흡연, 당뇨, 고혈압의 병력, 심전도 기록, 혈액학적 검사 그리고 관상동맥조영술 소견을 후향적으로 분석하였다. 결과: 475명의 대상 환자 중 86.3%인 410명에서 정상적인 혈류가 관찰되었으며(normal flow 군), 13.7%인 65명에서 reflow disturbance 현상이 관찰되었다(reflow disturbance 군). 재관류 시간이 142시간 이후에서는 reflow disturbance 현상이 관찰되지 않았다. 재관류 시간이 142시간 이내인 경우를 대상으로 다변량 분석을 시행한 결과, 연령(OR=1.03, 95% CI 1.01~1.06, p=0.020), 낮은 수축기 혈압(OR=0.98, 95% CI 0.97~0.99, p=0.026) 그리고 혈전이 있는 경우(OR=2.27 95% CI 1.08~4.79, p=0.031)가 reflow disturbance 현상의 유의한 독립적 위험인자였다. 결론: 급성 심근경색증으로 관상동맥 중재술을 받는 환자에서 고령, 낮은 수축기 혈압 그리고 혈전의 존재가 reflow disturbance 현상의 독립적인 위험인자로, 이러한 요인을 가진 경우는 시술시 주의가 필요하리라 사료된다. Background/Aims: The reflow disturbance phenomenon is associated with poor functional and clinical outcomes for patients suffering with acute myocardial infarction (AMI). In the era of primary coronary intervention (PCI), accurately identifying those lesions that are at a high risk of no-reflow is of crucial importance. Therefore, we investigated the risk factors of the reflow disturbance phenomenon in AMI patients who underwent PCI. Methods: From February 2003 to June 2005, the clinical and angiographic characteristics of 475 patients who had undergone PCI were reviewed retrospectively. Results: 65 patients (13.7%) showed the reflow disturbance phenomenon and the reperfusion times of the reflow disturbance group ranged from 1 hour to 142 hours. On univariate analysis, an older age (p<0.001), low systolic blood pressure (p=0.01), no thrombolysis followed by PCI (p<0.001), primary PCI (p<0.001), less time to PCI (p=0.001), a high peak serum CK-MB level (p=0.013), angiographically visible thrombus (p=0.016), a low pre-TIMI grade (p=0.021) and ST segment elevation on the ECG (p=0.002) were the significant risk factors of the reflow disturbance phenomenon. An older age, a low systolic BP and angiographically visible thrombus were significant risk factors on multivariate analysis. Conclusion: An older age, low systolic blood pressure and angiographically visible thrombus were the independent risk factors for the reflow disturbance phenonmenon in AMI patients who undergo PCI. (Korean J Med 74:16-22, 2008)

무선랜 시스템을 위한 계산이 간단한 초기 동기부 설계

조준범,이종협,한진우,유연상,오혁준,Cho, Jun-Beom,Lee, Jong-Hyup,Han, Jin_Woo,You, Yeon-Sang,Oh, Hyok-Jun 대한전자공학회 2012 전자공학회논문지 Vol.50 No.8

주파수 옵셋 보상, 프레임 동기화, Timing Recovery를 포함하는 동기화는 모든 유/무선 통신 시스템에서 가장 중요한 신호 처리 블록이다. 대부분의 통신 시스템에서는 Training sequences 또는 프리앰블을 기반으로하는 동기화 방법이 사용된다. IEEE에서 제정한 802.11a/g/n의 무선랜 표준은 OFDM 시스템을 기반으로 한다. OFDM 시스템은 주파수와 타이밍 동기화 에러에 대해서 싱클캐리어 시스템보다 더 민감한 것으로 알려져 있다. 프레임의 시작점과 OFDM 심볼 및 훈련심볼의 시작점은 상관관계를 이용하여 추정될 수 있다. 상관관계를 처리 기능을 하는 블록은 일반적으로 많은 수의 곱셈기로 인하여 큰 복잡도를 갖게 된다. 본 논문에서는 IEEE 802.11a/g/n 시스템을 위한 훈련심볼 내의 심볼값이 반복되는 특성을 활용한 복잡도가 현저히 낮은 동기화 기법을 제안한다. 시뮬레이션과 구현결과 제안된 기법이 기존의 방법보다 성능저하는 없는 반면 훨씬 적은 복잡도를 갖는 결과를 보여준다. Synchronization including timing recovery, frequency offset compensation, and frame synchronization is most important signal processing block in all wireless/wired communication systems. In most communication systems, synchronization schemes based on training sequences or preambles are used. WLAN standards of 802.11a/g/n released by IEEE are based on OFDM systems. OFDM systems are known to be much more sensitive to frequency and timing synchronization errors than single carrier systems. A loss of orthogonality between the multiplexed subcarriers can result in severe performance degradations. The starting position of the frame and the beginning of the symbol and training symbol can be estimated using correlation methods. Correlation processing functionality is usually complex because of large number of multipliers in implementation especially when the reference signal is non-binary. In this paper, a simple correlation based synchronization scheme is proposed for IEEE 802.11a/g/n systems. Existing property of a periodicity in the training symbols are exploited. Simulation and implementation results show that the proposed method has much smaller complexity without any performance degradation than the existing schemes.