민(MIN) 설계 방법을 이용한 무인기 수평이동제어 알고리즘에 관한 연구

왕현민(Hyun-Min Wang),허경무(Kyung-Moo Huh),우광준(Kwang-Joon Woo) 대한전자공학회 2009 電子工學會論文誌-SC (System and control) Vol.46 No.3

최근 무인기의 형태는 다양한 형태로 개발되고 있으며, 탑재 장비의 고성능 소형화를 바탕으로 무인기는 소형화 되고 있다. 이러한 소형화되고 일반적인 형태가 아닌 무인기 개발에 있어, 기존의 개발방법으로는 이러한 비선형적인 요소로 인하여 정확한 모델링 및 제어기 알고리즘의 정형화하기가 어렵다. 따라서 본 논문에서는 기존이 비행체 개발 방법이 아닌, 하중 제어 개념을 적용한 Min 설계 방법의 첫 번째 단계로, 원통형 무인기에 적용하여, 수평 비행 조건과 특성 그리고 제어기 설계 알고리즘을 찾아보았다. 이러한 Min 설계 방법은 고성능 컴퓨터를 사용한 무인기 개발에 있어 실시간 시뮬레이션을 통한 비용절감과 개발기간을 단축시킬 수 있다. Recently, UAV(unmanned aerial vehicle) has evolved into various figure and become miniaturized. On using existing design method, it is hard to make modelling and standardizing design of flight control system of the figure including cylinder like pipe. These problems are caused by uncorrect express of nonlinearity in controller design. Therefore, it is developed through step of correct modelling and simulation on real time using high efficiency computer in aircraft development of various figure. This is reducing period and expense of aircraft development. For the shake of solving these problems, Min-design method has been devised by H.M. Wang. In this paper, an object of control is cylindrical UAV instead of the general figure of aircraft. It was analyzed flight condition, specification about level flight of the UAV and was presented algorithm to find control value.

Forced suction thrombectomy in patients with acute ischemic stroke using the SOFIA Plus device

Roh Hyun Ki,Ju Min-Wook,Byoun Hyoung Soo,Park Bumsoo,Park Kwang Hyon,Jeongwook Lim 대한뇌혈관외과학회 2022 Journal of Cerebrovascular and Endovascular Neuros Vol.24 No.3

Objective: Stent retrieval thrombectomy has recently been the standard treatment for acute ischemic stroke with large artery occlusion. However, the development of catheters for suction thrombectomy has recently led to results comparable to that of stent retrieval thrombectomy (SRT). This study aimed to analyze the safety and efficacy of forced suction thrombectomy (FST) using the SOFIA Plus (MicroVention Terumo, Tustin, CA, USA) device.Methods: We included patients with acute ischemic stroke who underwent FST using the SOFIA Plus device at our institution. Medical records and angiographic data were reviewed, and the results of this study were compared with those of other FST studies.Results: A total of 35 patients were included in this study. The occlusion sites were the internal carotid artery terminal (4), M1 segment (20), and posterior circulation (11). Of the 35 patients, FST was performed in only 21 (60%) patients, and the remaining 14 (40%) patients underwent SRT and FST. In all cases, the recanalization rate was 100%, and the average time from groin puncture to recanalization was 21±4.94 min. In particular, the average time required to reach the SOFIA Plus lesions from the groin puncture was 10.44±5.06 min and about 67% of the FST patients were recanalized at the first attempt. Three-months modified Rankin Scale (mRS) score of ≤2 was observed in 52% of the patients.Conclusions: Forced suction thrombectomy using the SOFIA Plus yielded a high recanalization rate within a shorter time. In particular, the recanalization rate was higher than that reported in previous studies using other types of suction devices.

비행 물체의 유도제어 시스템 설계를 위한 하중(중력수) 제어 모델의 성능분석

왕현민(Hyun-Min Wang),우광준(Kwang-Joon Woo),허경무(Kyung-Moo Huh) 대한전자공학회 2009 電子工學會論文誌-SC (System and control) Vol.46 No.1

기존의 방법에서는 비선형 운동 물체의 운동 방정식을 선형화하므로써 비행체의 운동 상태방정식을 구하고, 각 제어 기관에 따라 전달함수를 구하여 안정성 판별과 더불어 제어기를 설계하였다. 이러한 설계 방법으로는 일반적인 비행기와 같은 형태, 비행 환경이 급격하게 변하지 않고 속도가 빠르지 않는 비행체의 유도/제어기 설계에 많이 사용되어 많은 성능을 발휘할 수 있다. 그러나 이러한 설계 방법은 통상적이지 않는 비행체 형태뿐만 아니라 빠른 속도에서 급격한 움직임을 갖는 비행체에서는, 기존의 유도/제어기 설계 방법으로는 이러한 비선형성으로인하여 제어성(경로문제)과 안정성(안정화문제)을 동시에 충족할 만한 성능을 발휘 할 수 없다. 따라서 본 논문에서는 이러한 불확실성이 내포된 비행체 제어 문제에서 제어성과 안정성을 동시에 충족시키기 위한 과정 중 먼저 제어성 문제를 해결하기 위한 비행체 제어성을 분석하고 모델을 제시한다. 또한 본 논문에서 비행체 모델과 동역학 모델에서 제어 요소로서 하중(중력수)을 설정하고 비행 특성에 따른 제어요소 값을 살펴본다. 이것은 Min 설계 방법 1단계이다. In conventional method, flight model is discribed to differential equation by linealization of nonlinear object motion equation. As state equation from differential equation of moving object, the controller is designed by transfer functions of each module under discrimination of stability criteria. But this conventional method is designed under limitation of nonlinearity from object's shape and speed. In other word, The greater part of guidance/navigation system was satisfied with the result of good performance for normal figure of flight object, not sudden changed flight condition, not high speed. But it is not able to give full play to its ability on flight object which has abnormal figure, sudden changeable motion, high speed. Therefore, in this paper was presented performance analysis of load control model for navigation/guidance system on flying object being uncertainty, non-linear like abnormal figure, sudden changeable motion, high speed and is presented method of trajectory control(controllability) ahead of controllability and stability to achieve flight mission. In other word, this paper shows the first step of Min-design method and flight control model.

국산 Lidocaine 알칼리화를 위한 Bicarbonate 혼합시 침전유발 최소량에 대한 고찰

이선호,김현수,곽인숙,안원식,최관호,김광민,손민제 대한마취과학회 2000 Korean Journal of Anesthesiology Vol.39 No.5

Background : When local anesthetics for regional anesthesia is used, usually small amounts of bicar-bonate are added for rapid onset. This addition gives the mixed solution a more alkaline pH. The following result is an increased unionized form of the local anesthetic and rapid penetration of the drug into tiissue. Unfortunately, no data about adequate mixing volumes of domestic lidocaine and bicarbonate is available. Methods : We examined six mixing pairs of two kinds of 2% lidocaines and three kinds of 8.4% bicarbonates for minimum volumes of bicarbonate to cause a precipitation of 2% 20 ml lidocaine. Results : The mean volumes of bicarbonate to cause precipitation were 1.54 ml for Kwang-Myung lidocaine with Kwang-Myung bicarbonate, 2.90 ml for Kwang-Myung lidocaine with Dae-Won bicarbonate, 2.73 ml for Kwang-Myung lidocaine with Je-Il bicarbonate, 0.97 ml for Je-Il lidocaine with Kwang-Myung bicarbonate, 1.26ml for Je-Il lidocaine with Dae-Won bicarbonate and 1.39 ml for Je-Il lidocaine with Je-Il bicarbonate. Conclusions : We conclude that the Kwang-Myung lidocaine and the Je-Il lidocaine could cause precipitation when mixing with a smaller bicarbonate volume than foreign textbook recommended. (Korean J Anesthesiol 2000; 39: 726-729)

정상 폐혈관 저항인 환장에서 일측 폐 환기시 흡입 투여된 Nitric Oxide가 산소화와 혈역학에 미치는 효과

김태성,이정원,김현수,김광민 대한마취과학회 1997 Korean Journal of Anesthesiology Vol.32 No.5

Background: Inhaled nitric oxide (NO) is a selective and potent pulmonary vasodilator. The authors hypothesized that inhaled NO at 40 ppm would improve parameters of oxygenation and pulmonary hemodynamics in patients undergoing one-lung ventilation in the lateral decubitus position by causing selective ventilated lung vasodilation. Methods: Six patients scheduled for thoracotomy operations were anesthetized with a thoracic epidural lidocaine (2%, 8ml/hr), intravenous fentanyl (2-5 ug/kg/min) and inhaled isoflurane (0.5 1.0%), and were monitored with radial and pulmonary artery catheters. After the patients were tumed into in the lateral decubitus position, the dependent lung was ventilated with 70% O2 and 30% N2 for 15 min for the control one-lung ventilation condition. For the study of one-lung ventilation condition, the dependent lung was ventilated with the same gas concentration with NO at 40 ppm for 15 min. During all conditions, pulmonary and systemic hemodynamics, intrapulmonary shunt and other parameters of ventilation were measured in a double blind method. Results: Baseline pulmonary vascular resistance during two-lung ventilation was 146.8+50.3 (SD) dynes sec cm. Administration of inhaled NO did not affect right-to-left intrapulmonary shunt, pulmonary vascular resistance, mean arterial pressure or systemic vascular resistance. Mean pulmonary arterial pressure remained unchanged during the administration of inhaled NO. Conclusions: Inhaled NO at 40 ppm does not significantly decrease ventilated lung PVR or improve oxygenation during one-lung ventilation in the lateral decubitus position in patients with normal pulmonary vascular resistance. This may be attributed to the inability of inhaled NO to further decrease normal baseline PVR exhibited by all patients enrolled in our study. (Korean J Anesthesiol 1997; 32: 761-767)

지르코니아 광페룰 사출성형용 WC 코아 핀의 Diamond Like Carbon 코팅

박현우,정세훈,김현영,이광민,Park, Hyun-Woo,Jeong, Se-Hoon,Kim, Hyun-Young,Lee, Kwang-Min 한국재료학회 2010 한국재료학회지 Vol.20 No.11

A diamond-like carbon (DLC) film deposited on a WC disk was investigated to improve disk wear resistance for injection molding of zirconia optical ferrule. The deposition of DLC films was performed using the filtered vacuum arc ion plating (FV-AIP) system with a graphite target. The coating processing was controlled with different deposition times and the other conditions for coating, such as input power, working pressure, substrate temperature, gas flow, and bias voltage, were fixed. The coating layers of DLC were characterized using FE-SEM, AFM, and Raman spectrometry; the mechanical properties were investigated with a scratch tester and a nano-indenter. The friction coefficient of the DLC coated on the WC was obtained using a pin-on-disk, according to the ASTM G163-99. The thickness of DLC films coated for 20 min. and 60 min. was about 750 nm and 300 nm, respectively. The surface roughness of DLC films coated for 60 min. was 5.9 nm. The Raman spectrum revealed that the G peak of DLC film was composed of $sp^3$ amorphous carbon bonds. The critical load (Lc) of DLC film obtained with the scratch tester was 14.6 N. The hardness and elastic modulus of DLC measured with the nano-indenter were 36.9 GPa and 585.5 GPa, respectively. The friction coefficient of DLC coated on WC decreased from 0.2 to 0.01. The wear property of DLC coated on WC was enhanced by a factor of 20.

Studies on Lytic, Tailed Bacillus cereus-specific Phage for Use in a Ferromagnetoelastic Biosensor as a Novel Recognition Element

( In Young Choi ),( Joo Hyeon Park ),( Kyoung Min Gwak ),( Kwang-pyo Kim ),( Jun-hyun Oh ),( Mi-kyung Park ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.1

This study investigated the feasibility of the lytic, tailed Bacillus cereus-specific phage for use in a ferromagnetoelastic (FME) biosensor as a novel recognition element. The phage was immobilized at various concentrations through either direct adsorption or a combination of 11-mercapto-1-undecanoic acid (11-MUA) and [N-(3-dimethylaminopropyl)-N’-carbodiimide hydrochloride and N-hydroxysuccinimide (EDC/NHS)]. The effects of time and temperature on its lytic properties were investigated through the exposure of B. cereus (4 and 8 logCFU/ml) to the phage (8 logPFU/ml) for various incubation periods at 22°C and at various temperatures for 30 and 60 min. As the phage concentration increased, both immobilization methods also significantly increased the phage density (p < 0.05). SEM images confirmed that the phage density on the FME platform corresponded to the increased phage concentration. As the combination of 11-MUA and EDC/NHS enhanced the phage density and orientation by up to 4.3-fold, it was selected for use. When various incubation was conducted, no significant differences were observed in the survival rate of B. cereus within 30 min, which was in contrast to the significant decreases observed at 45 and 60 min (p < 0.05). In addition, temperature exerted no significant effects on the survival rate across the entire temperature range. This study demonstrated the feasibility of the lytic, tailed B. cereus-specific phage as a novel recognition element for use in an FME biosensor. Thus, the phage could be placed on the surface of foods for at least 30 min without any significant loss of B. cereus, as a result of the inherent lytic activity of the B. cereus-specific phage as a novel recognition element.

농업 부산물 바이오매스 특성에 따른 반탄화 공정 최적화: 1. 질량감소 예측 모델 개발

김석준 ( Seok Jun Kim ),오광철 ( Kwang Cheol Oh ),박선용 ( Sun Young Park ),조라훈 ( La Hoon Cho ),김민준 ( Min Jun Kim ),이충건 ( Chung Geon Lee ),정인선 ( In Seon Jeong ),전영광 ( Yeong Kwang Jeon ),김대현 ( Dae Hyun Kim ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.2

본 연구에서는 국내에서 버려지고 있는 농업부산물의 에너지로서 이용 가능성이 분석되었다. 농업부산물 바이오매스는 화석연료와 동일하게 활용가능하며 지속적으로 생산되는 에너지원이다. 하지만 높은 수분 함량에 따른 보관문제, 화석연료와 비교하여 낮은 발열량등의 단점을 지니고 있어 전처리공정이 요구된다. 따라서 효율적인 활용을 위한 전처리 공정으로 반탄화가 선정되었다. 반탄화공정은 수분제거를 통해 에너지가 증가되어 저장·운송에 이점으로 인하여 최종적인 에너지 가치가 증대된다. 실험은 문헌탐색을 통한 반탄화공정 적용 가능 농업부산물(고추대)과 실험조건(200, 230, 270C, 10, 20, 30, 40 min)이 선정되었으며, 1차원 시뮬레이션을 통한 분석이 이루어졌다. 이때 반탄화 실험을 통하여 발생되는 질량감소량과 발열량 변화량은 높은 상관관계(r²=0.9528)를 가지고 있으며 본 연구에서는 반탄화공정의 질량감소량 예측 모델개발이 수행되었다. 질량감소량 분석을 위하여 열 중량 분석(Thermo Gravimetric Analyzer, TGA)이 수행되었으며 승온속도(5, 7.5, 15, 22.5, 30, 37.5°C min^-1)에 따른 반응속도상수가 도출되었다. 1차원 시뮬레이션 분석을 통하여 바이오매스 내부 온도를 예측하였으며 앞서 도출된 반응속도 상수를 이용하여 질량감소량이 예측되었다. 질량감소량 실험 및 시뮬레이션 결과 평균 r²=0.97로 상관관계를 나타내고 있으며 공정온도별 평균제곱근오차(Root Mean Square Error, RMSE)가 200°C-0.0165, 230°C-0.0191, 270°C-0.0207로 나타났다. 공정온도 증가에 따라 정확도가 감소되었으며, 이는 고온의 실험조건에서 발생되는 비응축가스와 온도변화에 의한 열분해 특성에 기인한 것으로 판단된다. 최종적으로 더 나아가서 질량감소 모델을 통한 발열량 예측을 위한 분석이 이루어져야한다.

뇌성마비 환자의 전신마취 하 치과치료

정준민,서광석,이영은,한희정,한진희,김혜정,신터전,김현정,염광원,장주혜,Chung, Jun-Min,Seo, Kwang-Suk,Yi, Young-Eun,Han, Hee-Jung,Han, Jin-Hee,Kim, Hye-Jung,Shin, Teo-Jeon,Kim, Hyun-Jeong,Yum, Kwang-Won,Chang, Ju-He 대한치과마취과학회 2008 Journal of Dental Anesthesia and Pain Medicine Vol.8 No.1

Background: Cerebral palsy (CP) is non-progressive disorder of motion and posture. In CP patient, there are difficulties in dental treatment because of uncontrolled movement of limb and head, and conjoined disabilities such as cognitive impairment, sensory loss, seizures, communication and behavioral disturbances. It is reported that CP patients have high incidence in caries and a higher prevalence of periodontal disease. But, despite the need for oro-dental care, these patients often are unlikely to receive adequate treatment without sedation or general anesthesia because of uncontrolled movements of the trunk or head. Methods: We reviewed the 58 cases of 56 patients with CP who underwent outpatient general anesthesia for dental treatment at the clinic for the disabled in Seoul National University Dental Hospital. Results: The mean age was 19 (2-54) years. The number of male patient was 40 and that of female was 18. They all had severe spastic cerebral palsy and 22 had sever mental retardation, 15 epilepsy, 8 organic brain disorder, 1 blindness, 2 deafness and cleft palate. For anesthesia induction, 14 cases was needed physical restriction who had sever mental retardation and cooperation difficulty, but 44 cases showed good or moderate cooperation. Drugs used for anesthesia induction were thiopental (37 cases), sevoflurane (14 cases), ketamine (3 cases ) and propofol (4 cases). All patients except one were done nasotracheal intubation for airway management and 4 cases were needed difficult airway management and 1 patient already had tracheostomy tube. Mean total anesthetic time was $174{\pm}56$ min and staying time at PACU was $88{\pm}39$ min. There was no death or long term hospitalization because of severe complications. Conclusion: If general anesthesia is needed, pertinent diagnostic tests and workup about anomaly, and appropriate anesthetic planning are essential for safety.

허혈성 심질환에 있어서 아데노신 급속 정맥투여후 관동맥압의 변화에 관한 연구

봉종대,오종용,배성한,신원용,김철현,이광희,최태명,현민수,김성구,권영주 순천향의학연구소 1998 Journal of Soonchunhyang Medical Science Vol.4 No.2

Background: Adenosine interacts with A1 receptors present on the extracellular surface of cardiac cells, activating K+channels in a fashion. It produces coronary vasodilatation and AV nodal block. The half-time is one to six second and has ultra-short action. In ischemic heart disease, fractional flow reserve(FFR) can be achieved safely with intravenous adenosine infusions at a rate of 150㎍/kg/min which cause maximal coronary hyperemia. Purpose: We investigated the patients who have had ischemic heart disease(n=8). After adenosine intravenous administration(150㎍/kg/min), the effect cause maximal hyperemia of coronary artery. During peak maximal hyperemia, we reported clinical findings, coronary hemodynamics and electrocardiogram findings. Methods: After diagnostic coronary angiography and left ventriculography, catheter was advanced into the ostium of coronary artery. We investigated coronary hemodynamics such as systolic coronary artery pressure, diastolic coronary artery pressure, mean coronary artery pressure and heart rate. To assess the use of adenosine for determination of fractional flow reserve, hemodynamics and electrocardiogram were measured at basal state and during peak maximal hyperemia. Results: Symptoms developed 1.5-2 minute after adenosine intravenous administration and each symptom disappeared 2-2.5 minute after adenosine administration. Two patients represented asymptomatic appearance and six patients complained of flushing, chest pain, palpitation and headache. In eight patients with ischemic heart disease, 1.5 minute after venous administration of 150㎍/kg/min of adenosine, coronary artery pressure decreased and heart rate increased significantly. Conduction abnormalities after administration of 150㎍/kg/min of adenosine were transient 2nd degree AV block 2 cases(25%). Conclusions: Adenosine is a potent ultra short-acting vasodilator. Although coronary artery pressure decreased and heart rate increased and mild cardiovascular symptoms occurred after continuous infusion of 150㎍/kg/min of adenosine, it is useful as an agent for determination of fractional flow reserve.