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      • 초음파 이송시스템의 진행파 제어에 관한 연구

        정상화,신상문,김태호,서호진,박진완 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1

        Methods of major transport system used in many industry fields are conveyor belt, magnetic levitation system and indexing system. It is an indispensable device in many fields and especially it is very important in the factory automation. However, the conventional transport system can damage precision optical components by the contact force and destroy the inner structure of semiconductor by the magnetic field. The new transport system for transporting without damage is required and the ultrasonic wave transport system has been proposed to replace the conventional transport system. In this paper. the object transport system using the ultrasonic wave is developed. Traveling waves are generated through the use of the ultrasonic wave generator to two ends of the beam. The modelling equation on steady state response of ultrasonic vibration is expressed through normal mode expansion. Natural frequency of flexural beam is estimated. Transport direction of the object is analyzed according to phase difference and frequency. In addition, it is verified by experiment.

      • 3축 제어용 시뮬레이터의 로드 프로파일 재현 소프트웨어 개발

        정상화,이규태,장완식,류신호 朝鮮大學校 機械技術硏究所 2001 機械技術硏究 Vol.4 No.2

        실제 운동조건과 같은 환경을 제공하는 다축 제어용 시뮬레이터는 설계나 평가에 있어 대단히 편리하면서도 경제적인 이점을 제공하여 준다. 일반적으로 완성차의 경우 설계에서부터 개발, 실험에 이르기까지 시간과 개발과정에 막대한 비용이 소모되고 있다. 그리고 자동차 부품업체에서는 완성차업체의 부품 검사서의 요구에 의해 시뮬레이터를 구비하고자 노력하고 있으나, 재현소프트웨어의 미비로 어려움을 겪고 있는 실정이다. 본 논문은 개발된 프로그램을 이용하여 기아자동차의 내구로(belgian road), 대우자동차의 도시로(city road), 고속도로(highway), 자갈로(gravel road)등의 신호를 입력하여 실제 실험을 수행함으로서 로드 프로파일 재현 소프트웨어의 타당성을 검증하였다. 이 과정에서 실험차량의 현가장치와 타이어가 비선형이기 때문에 초기 구동화일에 대한 응답신호는 요구되는 신호와 차이가 발생하였는데 이 오차는 반복 개선작업을 통하여 최소화시키면서 응답신호가 요구신호에 일치하도록 반복작업을 되풀이하였다. Full scale durability test in the laboratory is an essential of any fatigue life evaluation of components or structures of the automotive vehicle. Component testing is particularly important in today's highly competitive industries where the design to reduce weight and production costs must be balanced with the necessity to avoid expensive service failure. Generally, Hydraulic road simulator is used to carry out the fatigue test and the vibration test. In this paper, the algorithm and software to realize the real road profile are developed. The operation software for simultaneously controlled 3-axial simulator is developed and the input and output data are displayed window based PC controller in the real time. Futhermore, the software to generate the real road profile are developed. The validity of the software are verified by applying the belgian road, the city road the highway, and the gravel road. The results of the above experiment show that the real road profiles are realized well after 10th iteration. .

      • 실시간 분산 환경 감시를 위한 TMO 모델의 연구

        정윤석,김태완,장천현 건국대학교 산업기술연구원 2005 건국기술연구논문지 Vol.30 No.-

        We need an additional monitoring tool to observe a TMO model-based system because the conventional tools ae not based on the monitoring concept. Some studies have been conducted to develop a monitoring tool. But it is hard for them to support a distribued monitoring because they did not use a data sharing and delivery mechanism provided by the TMO model. To solve this problem, in this paper, we propose a TMO monitoring model which the TMO model and a monitoring concept are combined in. The model is composed of some components to support monitoring, and it guides the middleware to take all the monitoirng functions. Thus, a user can get monitored data provided by the middleware without any efforts. In addition, in this paper, we propose the MODS and MDC which are mechanisms to share or deliver the monitored data in distributed environments. These can resolve problems with conventional data stores used by the legacy monitoring tools, and provide a fundamental data management scheme to monitor several systems in distributed environments. The TMO monitoring model, MODS, and MDC can be used for a TMO system monitoring, performance evaluation, and monitoring tool development.

      • 구간 분할 제어를 이용한 형상기억합금 와이어의 온도제어에 관한 연구

        정상화,김주환,김태호,서호진,박진완 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1

        The key technology of robot is the design of the actuator. Particularly breakthroughs of power-to-weight ratio or energy-density III actuator technology have significant impacts upon the design and the control of robotic systems. To realize the anthropomorphic motion, artificial muscles such as shape memory alloy(SMA) and electro active polymer(EAP) are used. These actuators have the higher energy density than the electromechanical actuators such as the electric motor. The EAP has the property of good elasticity, but it is difficult to get the required power. The SMA has the good power density and simple structure, but the control scheme of the actuator is difficult. In this paper, temperature control of SMA wire using segment control is studied. The SMA wire is segmented by thermo-electric module(TEM). To supply constant currents in TEMs, MOSFET is used. Hysteresis in one segment of SMA wire is evaluated. The force and displacement of SMA wire are measured according to the number of segment. The program to control the temperature of TEM is developed by using LabVIEW software.

      • SCOPUSKCI등재

        단계적 온도 하강법을 이용한 췌도세포 냉동보존법

        정인경,오승훈,김병준,양태영,이병완,하창영,노정현,정재훈,민용기,이명식,이문규,김광원 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.26 No.1

        연구배경:최근 당뇨병의 새로운 치료법으로 시도되고 있는 췌도이식은 충분한 췌도수의 확보와 췌도생존율을 높이기 위한 면역억제제 사용이 제한점이 되고 있다. 본 연구의 목적은 이식 전 충분한 췌도 수의 확보를 위해 분리한 췌도를 냉동보존하는 방법을 확립하고 냉동보존한 백서 췌도세포의 시험관내 그리고 생체내 기능을 조사하였다. 방법:분리한 백서의 췌장소도를 48시간 배양한 후 한 시험관당 췌도세포 1000개씩 나누었다. 냉동보존은 6개의 시험관에 DMSO를 첨가한 후 초 냉각(supercooling), 핵화(nucleation)단계를 거친 후 99% isopropanol과 액체질소가 들어있는 dewer를 이용하여-0.25℃/분의 냉각속도로 -40℃까지 단계적으로 얼린후-70℃ 액체질소 탱크에 보관했다. 해동은 냉동시킨 vial들을 액체 질소 태으에서 꺼내 37℃ 항온조에 담가 급격히 해동시킨 후, 원심분리하여 상층액을 제거하고 각 vial에 0.75M sucrose 용액을 가한 후, 10% fetal calf serum이 함유된 RPMI 1640 media에서 배양하였다 각각 6개의 시험관에서 해동한 췌도들을 광학현미경 및 형광현미경하에서 췌도의 모양과 생존율에 대해 조사하고 인슐린 정적반응을 알아보았다. 또한 분리한 췌도를 냉동보존하지 않고 이식한 경우를 대조군(6마리)과 생체내 기능을 비교하였다. 결과:① 냉동보존후 획득한 췌도의 수와 생존율 해동후 획득한 췌도의 수는 해동시킨 당일날이 902±21, 24시간 배양 후에는 857±16, 72시간 후에는 817±18개로 점차 감소되었다. AO/PI 염색상 각 췌도의 생존율은 냉동 전을 100으로 하였을 때 해동당일, 24시간 후, 72시간 후가 각각 60±5, 80±5, 90±5%로 해동후 3일간 배양하였을 때 냉동전의 수준으로 회복하였다. ② 냉동보존후 췌도의 포도당에 대한 정적 인슐린 분비능:냉동직후 감소된 경향을 보였으나 해동후 3일간 배양한 췌도의 인슐린 분비는 냉동전과 통계적으로 의미있는 차이가 없이 냉동보존 전의 수준으로 회복되었다. ③ 냉동보존후 췌도의 포도당에 대한 동적 인슐린 분비능:냉동보존한 췌도를 해동후 3일째의 인슐린 동적 분비능은 냉동 전과 마찬가지로 자극 인슐린의 반응의 제1기와 2기가 잘 관찰되었다. ④ 냉동보존한 췌도세포 이식 후 혈당 변화:스트렙토조토신으로 유도된 당뇨병 쥐에 췌도이식 후 혈당은 냉동보존한 췌도이식군에서 대조군에 비해 혈당의 조절효과가 더 오래 지속되었다. 결론:소동물에서 단계적 온도 하강법을 이용한 췌도세포 냉동보존법을 확립하였으며 이는 기능, 구조 및 생존율에 큰 이상을 보이지 않았으므로 장차 사람의 췌도세포 동종이식시 부족한 췌도세포수를 극복하고 면역반응을 줄일 수 있는 매우 유용한 방법이 될 것으로 판단된다. Background : Although islet transplantation has been attempted to reverse the state of diabetes, achieving a critical number of islets and modulating the immune response limit the success of islet transplantation. Cryo-preservation of islets offers many important benefits for islet transplantation by collecting islets with a wide variety of HLA phenotypes and islet MHC expression. The aims of this study was to determine the optimal conditions for cryo-preservation by using a controlled cooling method and to evaluate in vitro and in vivo functional properties of the cryo-preserved islets. Methods : Collagenase-isolated, Ficoll-purified islets were cultured for 48 hours. They were aliquoted into freezing tubes (1000 islets per tube), equilibrated with 2M dimethyl sulfoxide (DMSO) in three steps, supercooled, nucleated, and controll-cooled at rate of 0.25℃/min to - 40℃ prior to storage at - 196℃. Rapid thawing and removal of DMSO with 0.75 M sucrose preceded 48 hour of culture and the morphology, viability, glucose-induced insulin secretion, and in vivo function of rats transplanted with cryopreserved islets was reexamined. Results : ① Recovery was 90.2±0.2%, 85.7±0.1% and 81.7±0.1% immendiately after, 24 hours and 72 hours after thawing respectively. The viability was 60±5%, 80±5%, 90±5% immediately after, 24 hours and 72 hours after thawing respectively. ② The glucose-stimulated-insulin secretion (GSIS) tended to decrease immediately after thawing, but GSIS increase to the level of pre-cryopreservation 72 hours after thawing. ③ The in dynamic GSIS, the first and the second phase of insulin secretion were well preserved in islets cultured for 72 hours after thawing. ④ The cryopreserved islets were cultured for 3 days and transplanted into renal sub-capsular space of streptozotocin (STZ) induced diabetic rats. The duration of normoglycemia in the STZ-induced diabetic rats transplanted with cryopreserved islets was significantly longer than of the fresh islets. Conclusion : The optimal condition of cryopreservation using the controlled cooling method was established in rat pancreatic islets. This cryopreservation method can be a feasible approach for human islet transplantation (J Kor Diabetes Asso 26:64~74, 2002).

      • 유니사이클 로봇에 대한 인간적 추론 제어 메카니즘

        김중완,안찬우,전태옥,전언찬,정희균 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.2

        Our unicycle has simple mechanical structure.But unicycle's dynamical system is a very sensitive unstable nonlinear system. equations of motion for a simple unicycle robot were derived using Lagrage's method. In this paper, a human fuzzy influence control mechanism was established throught an inquiry into human riding a unicycle, and we developed a hybrid controller to control our unicycle robot. This proposed hybrid controller is consisted with a pure PD and two fuzzy gain scheduled controllers and a direct fuzzy logic controller. Computer simulation results show that our hybrid controller has robust control performnance to unstable nnonlinear unicycle robot system.

      • 위암세포에 의한 종양침윤 림프구의 면역반응 억제기전에 관한 연구

        박정규,송규상,서광선,최정목,배진선,장일성,윤완희,노승무,조은경,백태현 大韓免疫學會 1995 大韓免疫學會誌 Vol.17 No.3

        Tumor-infiltrating lymphocytes ('1°ILs) interact most closely with tumor cells and thus are more likely to reflect tumor host interactions accurately. But it is unknown whether such T cells are nonspecific inflammatory cells or a subset of specific host immune responses. In this study, there was no clear correlation between the infiltration of T lymphocytes in stomach cancer and the overexpression of c-ErbB-2 or increasing class I MHC expression on tumor cells. A positive correlation was seen between the presence of TILs in the tumor and tumors with diploidy by flow cytometric DNA analysis. The proliferative responses of Ills stimulated with IL-2, anti-CD3 mAb, or both were examined. When compared to normal mucosal-associated lymphoid tissue lymphocytes, the proliferative response of TILs to high dose IL-2 was minimal. A similarly poor response to anti-CD3 mAb plus IL-2 was also observed. The freshly isolated TILs exhibit reduced ability to proliferate in response to IL-2, anti-CD3 mAb or both. The microenvironment of the tumor suppresses the proliferative capacity of the TILs. The mechanism of this suppression remains unknown. It could be mediated by suppressor cells, by soluble substances within the tumor, or both. To examine this question, supernatants of stomach cancer cells (SNSNU-1) were tested for the presence of immunosuppressive factors. Human peripheral blood T-cells and tumor-draining lymph node lymphocytes (TDLNL) were incubated for 3 days with SNSNU-1 and then assessed for proliferative responses to PMA, anti-CD28 mAb, or both and for the inducibility to express IFN- r or IL-4 mRNA to PMA. Peripheral blood T-cells pretreated with SNSNU-1 were unable to proliferate in response to PMA, anti-CD28 mAb or both. SNSNU-1 also produces inhibitory activities of TDLNL proliferative response to PMA or anti-CD28 mAb and PMA (49%, 52%, respectively). In contrast, culture supernatants obtained from HEp-2, K562 or Daudi showed normal proliferative responsiveness of peripheral blood T-cells and TDLNL by PMA, anti-CD28 mAb or both.

      • KCI등재

        측두하악관절의 초음파영상과 자기공명영상에서 하악과두 외측면과 관절낭간 거리 측정치 비교

        이태완,유동수,한원정,김은경 대한구강악안면방사선학회 2006 Imaging Science in Dentistry Vol.37 No.1

        Purpose : To evaluate the reliability and clinical usefulness of ultrasonography in the temporomandibular joint (TMJ). Materials and Methods : Parasagittal and paracoronal 1.5 T MR images and 7.5MHz ultrasonographs of 40 TMJs in 20 asymptomatic volunteers were obtained. Disc position using MR imaging was evaluated and the distance between the lateral surface of mandibular condyle and the articular capsule using MR image and ultrasonograph of 27 TMJs with normal disc position was measured and compared. Intraobserver and interobserver measurements reliability was evaluated by using interclass correlation coefficients(ICC) and measurement error. Also, the distance measured on ultrasonographs was compared, according to mouth position and disc postion. Results : The normal disc position was found in 27 of 40 asymptomatic joints. At the intraobserver reliability of measurement, ICC at the closed and open mouth position were 0.89 and 0.91. The measurement error was 0.4% and 0.5%. At the interobserver reliability, ICC at the closed and open mouth position were 0.92 and 0.81. The measurement error was 0.4% and 0.7%. At the TMJ with normal disc position, the distances between the lateral surface of mandibular condyle and the articular capsule measured on MR images and ultrasonographs were 2.0±0.7 mm, 1.8±0.5 mm, respectively(p<0.05). On the ultrasonographs, the distances at open mouth position were 1.2±0.5 mm (p<0.05). At the TMJ with medially displaced disc, the distances at the closed and open mouth position were 1.3±0.3 mm and 0.9±0.2 mm (p<0.05). Conclusion: The results suggest ultrasonography of TMJ is a reliable imaging technique for assessment of normal disc position. (Korean J Oral Maxillofac Radiol 2006; 36 : 41-8)

      • KCI등재후보

        한국판 사건충격척도 수정판의 신뢰도 및 타당도 연구

        은헌정,권태완,이선미,김태형,최말례,조수진 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.3

        Objectives : The present study was conducted to explore the reliability and validity of the "Impact of Event Scale-RevisedKorean version" (IES-R-K). Methods : The subjects were college students who visited a college counseling center and patients who were admitted to a general hospital and two orthopedic local clinics.Those subjects who experienced catastrophic traumatic events were tested for CAPS, BDI, STAI-I, II, and MMPI-PTSD scale. Results : The range of correlations between item-total were .45 -.89. The coefficients of internal consistency were .69 -.83, of them were the Split-half reliability was .71 and the test-retest reliability was .89, all within expected ranges. Inter-corre-lations of IES-R-K, CAPS, BDI, STAI-I, II, and MMPI-PTSD scale were high. CAPS showed the highest correlation Coef-ficient. Factor analysis indicated 4 factors in IES-R ; avoidance, hyperarousal, intrusion, and sleep problem & numbness. IES-R-K can be a useful self-rating diagnostic instrument for PTSD symptoms to be a clinical concern by using 24/25 cutoff in total score. The partial PTSD cutoff score is 17/18. Conclusion : The IES-R-K was confirmed in it's reliability and validity. IES-R-K could be applied for screening of PTSD.

      • 화농성 슬관절염이 동반된 수막구균성 수막염 1예

        김태연,유진홍,박성환,김연식,임상현,신완식,강문원,정창훈,최문구,강지민 대한화학요법학회 1997 대한화학요법학회지 Vol.15 No.2

        저자들은 최근 화농성 슬관절염과 병발한 수막구균성 수막염 1예를 체험하였고, 이는 국내에서 아직 보고되지 않은 드문 예로 사료되어 문헌고찰과 함께 보고하는 바이다. We recently experienced a case of meningococcal meningitis associated with pyogenic arthritis in a 37-year old male patient. Pyogenic arthritis developed in right knee joint during treatment for meningococcal meningitis. He was treated successfully by appropriate antibiotics and arthroscopic irrigation. To our knowledge, such a rare case has not ever been reported in Korea, Hence we report this case with a review of related literatures.

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