Model Predictive Control Based Multifunctional Advanced Driver-Assistance System Specialized for Rear-End Collision Avoidance

이황재,최세범 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.3

This paper presents the model predictive control (MPC) based multifunctional advanced driver-assistance system (MADAS) that is optimized for rear-end collision avoidance. First, the system’s operation is judged by considering the driver’s intention of avoidance and the possibility of avoiding obstacle vehicles. Once the system is activated, the lateral tire force corresponding to the driver’s steering input, which is essential for collision avoidance, is realized with the highest priority. The use of each tire friction circle is then maximized by utilizing available tire forces for braking through quadratic programming. While the MADAS ensures the lateral maneuver and deceleration of the vehicle, the system still can generate additional yaw moment calculated from the MPC, the upper level controller, to track the driver’s desired yaw rate or prevent the vehicle from becoming unstable. The nonlinearity inevitably encountered in maximizing tire forces is reflected through the extended bicycle model and the combined brushed tire model. The proposed system is verified by the vehicle dynamics software CarSim, and the simulation results show that the MADAS performs better in rear-end collision avoidance situations than conventional advanced driver-assistance systems (ADAS).

컨테이너 항만의 위험평가-인천항을 중심으로-

이황재,하민호 한국물류학회 2022 물류학회지 Vol.32 No.4

This study is the second step in a series of research on risk management and evaluation of container ports in Korea and focuses on the development of the risk evaluation framework. And then, the framework was applied to Incheon port to evaluate the risk levels of the selected risk factors and the total risk level in the context of container operations. The port risk evaluation framework developed in this study is a hybrid model of the FER algorithm and Utility Techniques by incorporating AHP to evaluate the weights and risk level of each risk factor, leading to driving the weighted risk level of the individual risk factor as well as the total risk level of the alternative port. Consequently, the results obtained by the risk evaluation model are expected to be used by port risk managers as diagnostic tools to mitigate port risk or to improve risk management practices. In addition, the results will be used as basic data for the risk control options(RCOs) selection and the cost-benefit(C/B)analysis for further study. 본 연구는 국내 컨테이너항만 위험관리 및 평가에 관한 연속연구의 두 번째 단계의 연구로 항만위험을 평가하기 위한 위험평가모델을 개발하고 이를 인천항에 적용하여 인천항 컨테이너항의 위험을 평가한다. 본 연구에서 제시하는 항만위험평가모델은FER algoritum과 Utility Techniques을 기반으로 AHP를 결합한 것이며, 이를 통해 각 위험요인의 중요도와 각 위험요인의 순수 위험수준을 각각 계산 및 통합하여 모든 계층 위험요인의 가중위험수준 및 항만 전체의 가중위험수준을 도출하였다. 본 연구에서제시하는 분석결과는 항만 위험관리자들이 항만위험을 완화 또는 위험관리 개선을 위한 진단 도구로 활용될 것으로 기대된다. 또한, 본 연구 결과는 향후 항만위험을 완화하기 위한 전략인 위험제어옵션(Risk Control Options) 선택 연구와 선정된 위험제어옵션에 대한 비용편익분석(Cost Benefit Analysis) 연구의 기초자료로 활용될 것이다.

Online Detection of Toe Angle Misalignment Based on Lateral Tire Force and Tire Aligning Moment

이황재,최세범 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.3

Wheel alignment of a vehicle composed of toe, camber and caster is essential for stable driving. Among them, the toe angle can be easily adjusted in many commercial vehicles when misaligned. However, there have been many difficulties for a driver to directly detect the misalignment of the toe angle. To solve this problem, this paper proposes a novel system that detects misaligned toe angle in real-time by utilizing the lateral tire force and tire aligning moment. The system is largely divided into the lateral tire force model construction, tire aligning moment model construction, and misalignment detection. During the lateral tire force model and the tire aligning moment model construction, linearized recursive least squares are used to identify parameters necessary for the building of the models. Afterwards, during the misalignment detection, the misaligned toe angle is detected in real-time without additional sensors by estimating the slip angle of each wheel reflecting the toe angle effect based on these two models. The proposed system is verified by the vehicle dynamics software CarSim, and the simulation results show that misaligned toe angle can be successfully detected in real-time while driving.

Photothermal hydrogelation in vivo

이황재,이재영,김세민,정솔찬 한국고분자학회 2014 한국고분자학회 학술대회 연구논문 초록집 Vol.2014 No.10

백서에서 GLUCOCORTICOIDS 투여시 골결손부 치유에 미치는 영향에 관한 연구

이황재,김경욱,이재훈 단국대학교 치과대학 구강악안면외과학교실 1996 단국 구강악안면외과학 논문집 Vol.4 No.1

2001년도 EMC기준전문위원회 활동방향

이황재 한국전자파학회 2001 전자파기술 Vol.12 No.1

재활 초음파 영상을 이용한 젊은 성인의 하지 근 구조 비교: 서울과 하노이 하지 근 단면적비교 연구

이황재,김민규,하현근,이완희,Lee, Hwang-Jae,Kim, Min-Kyu,Ha, Hyun-Geun,Lee, Wan-Hee 대한물리치료학회 2014 대한물리치료학회지 Vol.26 No.5

Purpose: The aim of the current study was to compare the muscle architecture of lower extremity using rehabilitative ultrasound imaging (RUSI) in young adults in Seoul and Hanoi. Methods: The study design was a comparative study of muscle cross-sectional area of lower extremity. Sixty healthy young subjects (Seoul group: 30, Hanoi group: 30) participated in this study. Real-time B-mode RUSI with a 7.5MHz linear transducer was used for measurement of cross-sectional area, pennation angle, and muscle thickness of the rectus femoris, tibialis anterior, and medial gastrocnemius muscles. Independent t-test was used for statistical analysis. Results: Significant difference in cross sectional area of rectus femoris was observed between Korean young adults and Hanoi young adults (p<0.01). Muscle thickness and pennation angle of tibialis anterior in Korean young adults were greater than in Hanoi young adults (p<0.01). In addition, the muscle thickness and pennation angle of the medial part of gastrocnemius muscle were greater in Korean young adults than in Hanoi young adults (p<0.01). In addition, in the results for gender, men had larger muscle architectures than women in both groups (p<0.01). Conclusion: This study, using RUSI, showed significant difference in muscle architectures of lower extremity in a diverse group of young adults RUSI.

성별에 따른 술호 경막외자가통증조절에 있어서 Butorhpanol과 Fentanyl의 비교

이황재,진영준,정찬종 대한마취과학회 2000 Korean Journal of Anesthesiology Vol.39 No.3

Background: Differences between sexes in sensitivity to nociceptive stimuli and response to analgesics have been noted in humans and animals. Male rats are more sensitive than female rats to the antinociceptive properties of morphine. Kappa-opioid analgesia is greater in women than in men. The purpose of this study was to evaluate the difference between the sexes in postoperative analgesic responses to patient-controlled epidural analgesia (PCEA) with butorphanol or fentanyl in 0.05% bupivacaine solution. Methods: After obtaining their consents, 30 men and 30 women, less than 60 years old, undergoing elective gastrectomy under general anesthesia were randomly allocated into four groups of 15 butor-phanol-female, butorphanol-male, fentanyl-female and fentanyl-male. An epidural catheter was introduced at the T7-8 or TS-9 interspinous space before the operation. Postoperative analgesia was provided with PCEA with butorphanol 50 ㎍/ml or fentanyl 5 pg/ml in a 0.05% bupivacaine solution. When patients first requred analgesics after complete recovery of consciousness from anesthesia, a bolus of 5 ml was initially administered. The PCEA device was set to deliver a bolus of 2 ml, a lockout interval of 10 min and no basal infusion. PCEA consumption, pain intensity using a 10-cm visual analog score (VAS), patient's satisfaction to PCEA and side effects were evaluated at 3, 6, 24, and 48 h after the surgery. Results: Cumulative PCEA consumption with butorphanol was less in the butorphanol-female group than in the butorphanol-male group at 24 and 48 h postoperatively. VAS pain scores and patients satisfaction to PCEA were not different between the butorphanol-female group and the butorphanol-male group. Cumulative PCEA consumption with fentanyl was less in the fentanyl-male group than in the fentanyl-female group at 6, 24 and 48 h postoperatively. VAS pain scores and patients' satisfaction to PCEA were not different between the fentanyl-female group and the fentanyl-male group. There was no differece in side effects in both butorphanol groups and in both fentanyl groups. Conclusion: For postoperative analgesia with PCEA, butorphanol may be better for females than males, and fentanyl may be better in males than in females.

다형성선종에서 연골유래형성단백의 발현

이황재(Hwang-Jae Lee),김철환(Chul-Hwan Kim),김경욱(Kyung-Wook Kim) 대한구강악안면외과학회 2007 대한구강악안면외과학회지 Vol.33 No.3

The bone morphogenic protein(BMP) can promote migration and growth of mesenchymal cells and initiate process for bone and cartilage formation. Cartilage-derived morphogenic protein(CDMP)-1 and -2 belong to the bone morphogenetic protein family in the transforming growth factor(TGF)-βsuperfamily. Although pleomorphic adenoma of the salivary glands is an epithelial tumor, it frequently shows ectopic cartilaginous formation with biomolecular studies. The mechanism of pathogenesis in cartilaginous formation is still controversy. We examined the expression and localization of CDMP-1 and -2, in comparison with the localization of cartilaginous matrix proteins, in human normal salivary glands and 20 cases of pleomorphic adenoma using immunohistochemical methods. The results were followed. 1. CMP-1 was immunolocalized in the striated ducts and the intercalated ducts , but not expressed in excretory duct, CDMP-2 was not expressed in the normal salivary glands. 2. CMP-1 was immunolocalized in the ductal cell and cuboidal neoplastic myoepithelial cells around the chondroid areas of the pleomorphic adenomas, whereas these molecules were not localized in the spindle-shaped neoplastic myoepithelial cells of the myxoid element in these tumors. CDMP-2 was expressed neither in normal salivary glands nor in any elements of the pleomorphic adenomas. 3. In transmission electron microscopic view, the tumor cells are composed of modifed myoepithelial cells between hyaline and myxoid stroma. 4. In Immuno-blot analysis, strong overexpression of CDMP-1 was frequently seen in pleomorphic adenomas, but the level of CDMP-2 was expressed minimally in pleomorphic adenoma. From the these results, it should be suggested that undifferentiated neoplastic myoepithelial cells around the chondroid areas expressed CDMP-1 and suggested that this molecule may play a role in the differentiation of neoplastic myoepithelial cells in pleomorphic adenoma, but not CDMP-2.

컨테이너 항만의 위험요인 식별 및 중요도 평가

이황재(Lee, Hwang-Jai),하민호(Ha, Min-Ho) 한국물류학회 2021 물류학회지 Vol.31 No.6

본 연구는 국내 컨테이너항만 위험관리 및 평가에 관한 연속연구의 첫 단계 연구로 항만 전문가 그룹의 관점에서 컨테이너 항만의 위험요인 식별 및 선정된 위험요인의 중요도를 평가한다. 국내 컨테이너 항만위험 관련 연구가 부족하여 해외 항만위험관리에 관한 연구에서 위험요인의 추출이 주로 이루어졌으며, 선정된 위험요인을 국내 컨테이너항만에 적용할 수 있는지 항만 전문가와 인터뷰를 통해 최종 5개 대분류 이하 19개 컨테이너 항만 위험요인을 선정하였다. AHP 결과에 따르면 인적 관련 위험요인, 환경 관련 위험요인 및 장비 관련 위험이 상대적으로 중요한 것으로 평가되었으며, 이는 의사결정자가 잠재적 사고를 방지하기 위해 이러한 요인에 자원 배분 등 최우선 순위를 두어야 한다는 것을 의미한다. 더욱 중요한 것은 이 연구의 결과가 위험요인의 발생가능성과 발생 시 결과 심각도와 결합 되어 향후 우리나라 컨테이너 위험평가 시 다양한 항만 위험평가 모델의 적용에 활용될 것이다. This study is the first step in a series of research on risk management and evaluation of container ports in Korea and focuses on the identification of the risk factor and the evaluation of the risk factor priority by taking perspective from a port expert group. Due to the lack of studies on the container port risk domain in Korea, the extraction has mainly been made from previous studies on overseas port risk management. 19 container port risk factors under 5 dimensions were selected through interviews with port experts by asking whether the selected risk factors can be applied to Korean container ports. According to AHP results, 3 dimensions of the human-related factors, environmental factors, and equipment-related factors were evaluated as important, which represents decision-makers should put their first priority on these factors to prevent potential accidents. More importantly, the results of this study are expected to be used in the application of various port risk assessment models by combining the occurrence likelihood of risk factors and the consequence severity of risk factors.