CVVL BLDC 모터의 열피로 가속시험을 통한 수명보증시험 설계

이상훈(San-Hoon Lee),박상욱(Sang-Wook Park),김민근(Min-Geiun Kim),선한걸(Han-Geol Seon),홍성렬(Sung Ryeul Hong),한만승(Man-Seung Han) 한국신뢰성학회 2015 신뢰성응용연구 Vol.15 No.4

Purpose : The demand for higher fuel economy vehicles has helped develop fuel-efficient vehicles such as a CVVL called continuous variable valve lift. Existing CVVL has been applying DC type motor to control intake valve, but recently some car parts manufacturers have been developing a BLDC type CVVL motor for improvements of endurance performance. The purpose of this study is to find the potential failure mechanism of the CVVL BLDC moto in early stage of development based on the design properties and design the accelerated life test model. Methods : CVVL BLDC is consist of brushs, coil, magnetic, PCB, bearing and so on. Each component has a latent failure mechanism caused by temperature, humidity, vibration. By analysis result of the failure mechanism, thermal fatigue is the most important factor of a durability of CVVL BLDC motor. So, we designed a new accelerated life test model for guarantee of the CVVL BLDC motor. Results : A crack occurred on via hole in test using the conditions we designed, so we did change the design to avoid this failure. The via hole dimension is changed a little larger, as a result we achieve improvements in reliability of the CVVL BLDC motor. By applying various kinds and extreme level of stresses, we can find the operating limits of products. Conclusion : In thesis, We analyzed the failure mechanism of CVVL BLDC and designed an accelerated life test method to give a guarantee for reliability. Based on the test results, we could improve the reliability of developments by change of design.

초음파 가진에 의한 마이크로 버블의 공진특성 해석

이상훈(San-Hoon Lee),김노유(Nohyu Kim) 한국비파괴검사학회 2023 한국비파괴검사학회 춘계학술대회 초록집 Vol.2023 No.5

간이식 환자에서 발생한 Nocardia farcinia 폐렴 및 패혈성 쇼크

이수환 ( Su Hwan Lee ),박병훈 ( Byung Hoon Park ),손지영 ( Ji Young Son ),정지예 ( Ji Ye Jung ),김은영 ( Eun Young Kim ),임주은 ( Ju Eun Lim ),이지훈 ( Ji Hoon Lee ),현신영 ( Shin Young Hyun ),이상훈 ( Sang Hoon Lee ),이상국 ( San 대한결핵 및 호흡기학회 2010 Tuberculosis and Respiratory Diseases Vol.69 No.6

Nocardia farcinia, an aerobic, gram-positive bacilli actinomycetes of the genus Nocardia, is an uncommon pathogen found in humans. The most common Nocardia infection sites are the lung, central nervous system, and skin. Even though hematogenous dissemination can occur, isolation of the organism from blood cultures is very rare. We report a case of Nocardia infection that was isolated on blood cultures. A 59-year-old male with a medical history that includes a liver transplantation 6-years prior due to hepatocellular carcinoma secondary to chronic hepatitis B, developed pneumonia and was transferred to Severance Hospital. At the time of admission, the patient`s initial exam showed hypothermia, tachypnea, and hypotension. His chest radiograph showed severe pneumonia and a large abscess on left upper lobe. Under the presumptive diagnosis of bacterial pneumonia or other opportunistic infection, we started broad spectrum antibiotics. However, he developed Nocardia sepsis, rapidly deteriorated, and subsequently died.

비만에서의 식이요법

이상훈 ( Sang Hoon Lee ),김산하 ( San Ha Kim ),박성철 ( Sung Chul Park ) 대한소화기학회 2024 대한소화기학회지 Vol.83 No.3

Obesity is defined as a condition characterized by the abnormal accumulation of fat cells, which results in increased body weight. Worldwide, obesity is progressively on the rise, leading to an increased prevalence of chronic conditions such as cardiovascular disease, type 2 diabetes, and hyperlipidemia. Obesity is a result of the interplay between genetic, metabolic, social, behavioral, and cultural factors, necessitating an interdisciplinary and multimodal management approach. Diet therapy, which includes dietary modifications and nutritional interventions, is a fundamental component of the multifaceted approach to managing obesity. The principle of diet therapy is based on achieving weight loss through a negative energy balance and maintaining weight through an equilibrium of energy intake and expenditure. Strategies for weight loss and control rely on caloric restriction, macronutrient distribution, and dietary patterns such as the Mediterranean and Dietary Approaches to Stop Hypertension (DASH) diets. Recently, studies have been conducted on weight control using information and communication technology-based interventions, as well as interventions based on intestinal microorganisms which consider inter-individual variability and long-term adherence. In conclusion, diet therapy stands as a pivotal element in the management of obesity, providing a personalized and comprehensive approach to weight control. By combining evidence-based dietary strategies with behavioral modifications and consistent support, healthcare professionals can enable individuals to attain and sustain a healthier weight, thereby reducing related health risks. (Korean J Gastroenterol 2024;83:87-93)

사이버나이프에서 폐종양 추적 시스템의 정확도 분석

허현도,최상현,김우철,김헌정,김성훈,조삼주,민철기,조광환,이상훈,최진호,임상욱,신동오,Huh, Hyun-Do,Choi, Sang-Hyoun,Kim, Woo-Chul,Kim, Hun-Jeong,Kim, Seong-Hoon,Cho, Sam-Ju,Min, Chul-Ki,Cho, Kwang-Hwan,Lee, Sang-Hoon,Choi, Jin-Ho,Lim, San 한국의학물리학회 2009 의학물리 Vol.20 No.3

사이버나이프 로봇 방사선 수술 시스템은 환자를 치료하는 동안 환자의 내부 기준 마커를 이용하여 종양의 위치를 실시간으로 추적 할 수 있는 시스템이다. 최근 폐종양 치료의 경우 기준 마커의 삽입 없이 폐종양의 밀도 차이를 이용하여 실시간 종양 추적을 할 수 있는 폐종양추적시스템이 개발되어 치료에 적용되고 있다. 최근 개발되어 국내 최초 도입된 폐종양 추적치료시스템의 위치 추적 정확도의 분석은 동적흉부 팬톰과 GafChromic film을 이용하였다. 폐종양추적시스템을 이용하여 종양의 위치 추적 정확도는 평균 오차 $0.85{\pm}0.22$ mm로 분석되었다. 기준마커 삽입 없이 폐종양추적시스템을 이용하여 폐종양 치료에 매우 유용한 것으로 판단되었다. To track moving tumor in real time, CyberKnife system imports a technique of the synchrony respiratory tracking system. The fiducial marker which are detectable in X-ray images were demand in CyberKnife Robotic radiosurgery system. It issued as reference markers to locate and track tumor location during patient alignment and treatment delivery. Fiducial marker implantation is an invasive surgical operation that carries a relatively high risk of pneumothorax. Most recently, it was developed a direct lung tumor registration method that does not require the use of fiducials. The purpose of this study is to measure the accuracy of target applying X-sight lung tracking using the Gafchromic film in dynamic moving thorax phantom. The X-sight Lung Tracking quality assurance motion phantom simulates simple respiratory motion of a lung tumor and provides Gafchromic dosimetry film-based test capability at locations inside the phantom corresponding to a typical lung tumor. The total average error for the X-sight Lung Tracking System with a moving target was $0.85{\pm}0.22$ mm. The results were considered reliable and applicable for lung tumor treatment in CyberKnife radiosurgery system. Clinically, breathing patterns of patients may vary during radiation therapy. Therefore, additional studies with a set real patient data are necessary to evaluate the target accuracy for the X-sight Lung Tracking system.

험지에서의 가변 휠형 무인 자율차량의 자세 제어를 위한 가변 휠의 형상 계획

임경빈(Kyeong Bin Lim),박석훈(Sukhoon Park),윤용산(Yong San Yoon),이상훈(Sang Hoon Lee),강신천(Shincheon Kang) 대한기계학회 2009 大韓機械學會論文集A Vol.33 No.3

Hybrid locomotive UGV with actively articulated legs along with wheeled ends has high traversability to travel over rough terrain. The behavior control method was usually adapted for the controlling of the suspension configuration which determines the traversability of the UGV. In this study, we are proposing a method of configuration planning of the legs without any detail geometric data about the terrain. The terrain was estimated by the traces of each wheel and the leg configurations for the desired posture of the vehicle were set up against the constraints of the terrain. Also, an optimal leg configuration was calculated based on the quasi-static stability and power consumption, and plans for the leg behavior were made. Validity of the proposed method was checked by simulations using some off-the-shelf programs, and showed that the orientation control without geometric features of terrains and simplification of the behavior planning for obstacle negotiation were possible.

가변 휠형 무인자율차량의 접촉휠 예측 모델

임경빈(Kyeong Bin Lim),김선재(Sun Je Kim),박석훈(Sukhoon Park),윤용산(Yong-San Yoon),이상훈(Sang Hoon Lee) 대한기계학회 2009 大韓機械學會論文集A Vol.33 No.8

Wheels of UGV can be used to get the information about the ground. However, wheels of UGV with actively articulated suspension cannot be used as the roles because the each wheel does not remain in contact with the ground. Therefore, in this study, we proposed the indexes and models to estimate the contact wheels. First, we formulated the dynamic equations about the actively articulated suspensions and wheels. Then estimation index IWTC and IATC were developed from the equations, and analyzed the strengths and weaknesses of each index. As the results, we developed the fuzzy rule-based estimation model additionally derived from our observations. IWTC model and IATC model could eliminate the noise of about 60% in comparison with the result without the estimation model. Fuzzy model also could reduce the noise of about 83%. In addition, fuzzy rule-based estimation model had high sensitivity and precision as well as robustness.