• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권12호
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• pp.2355-2373
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• 2011

Vision-based vehicle detector systems are becoming increasingly important in ITS applications. Real-time operation, robustness, precision, accurate estimation of traffic parameters, and ease of setup are important features to be considered in developing such systems. Further, accurate vehicle detection is difficult in varied complex traffic environments. These environments include changes in weather as well as challenging traffic conditions, such as shadow effects and jams. To meet real-time requirements, the proposed system first applies a color background to extract moving objects, which are then tracked by considering their relative distances and directions. To achieve robustness and precision, the color background is regularly updated by the proposed algorithm to overcome luminance variations. This paper also proposes a scheme of feedback compensation to resolve background convergence errors, which occur when vehicles temporarily park on the roadside while the background image is being converged. Next, vehicle occlusion is resolved using the proposed prior split approach and through reasoning for rule-based tracking. This approach can automatically detect straight lanes. Following this step, trajectories are applied to derive traffic parameters; finally, to facilitate easy setup, we propose a means to automate the setting of the system parameters. Experimental results show that the system can operate well under various complex traffic conditions in real time.

• International Journal of Automotive Technology
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• 제7권1호
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• pp.91-99
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• 2006

The diesel Auxiliary Power Unit (APU) for vehicle applications is a complex nonlinear system. For the purpose of this paper presents a dynamic average model of the whole system in an entirely physical way, which accounts for the non-ideal behavior of the diode rectifier, the nonlinear phenomena of generator-rectifier set in an elegant way, and also the dynamics of the dc load and diesel engine. Simulation results show the accuracy of the model. Based on the average model, a simple PI control scheme is proposed for the multivariable system, which includes the steps of model linearization, separate PI controller design with robust tuning rules, stability verification of the overall system by considering it as an uncertain one. Finally it is tested on a detailed switching model and good performances are shown for both set-point following and disturbance rejection.

• 전자공학회논문지S
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• 제34S권11호
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• pp.126-137
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• 1997

This paper describes the algorithm which can estimate road following direction and deetect obstacle using a monocular vision system. This algorithm can estimate the course of vehicle using the vanishing point properties and detect obstacle by statistical method. The proposed algorithm is composed of four steps, which are lane prediction, lane extraction, road following parameter estimation and obstacle detection. It is designed for high processing speed and high accuracy. The former is achieved by a small area named sub-windown in lane existence area, the later is realized by using connected edge points of lane. We would like to present that the new mehod can detect obstacle using the simple statistical method. The paracticalities of the processing speed, the accuracy of the algorithm and proposing obstacle detection method, have been justified through the experiment applied VTR image of the real road to the algorithm.

• 한국자동차공학회논문집
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• 제4권2호
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• pp.90-105
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• 1996

A real tine simulator of running power train for a construction vehicle was developed. The simulator mainly consists of following two parts; (1) running power train part and (2) running load generation part. An optimal servo control algorithm was adopted for designing the multi-variable digital control system of the simulator. By experiments investigating response characteristics under step-wise variation or pre-determined scenario of target vehicle velocity and target load torque, it was verified that the simulator could reproduce physical situations at and actual vehicle with excellent similarity.

• 한국정밀공학회지
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• 제14권7호
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• pp.137-143
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• 1997

In this study, handling simulation of a passenger car is carried out to see the effects of suspension compliance, roll stabilizef bar and chassis flexibility. The front suspension of the car is a MacPherson strut type and the rear suspension is a multi-link type. The following five DADS models are constructed and compared to verify the effects of suspension compliance and chassis flexibility during lane change. (1) Vdhicle model without hard point compliance and stabilizer, (2) Vehicle model with hard point compoiance, (3) Vehicle model with hard point compliance and stabilizer, (4) Vehicle model with hard point compoiance, stabilizer, and one vibration mode of the chaxxis. (5) Vehicle model with hard point compliance, stabilizer, and three vibration modes of the chassis. The result shows that hard point compliance and stabilizer are significant in roll angle, and the flexibility of the chassis affects the yaw angle and yaw rate.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 춘계학술대회
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• pp.105-108
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• 2010

자동차 내비게이션 시스템은 경로탐색 및 길안내 등의 기능을 제공하는 대표적인 운전자 지원 시스템의 하나로서 그 사용성이 크게 증가하고 있다. 내비게이션의 시장 확산에 따른 경쟁 상황에서 신규 서비스 기능에 대한 소비자 기대감 충족을 위한 차별화된 서비스의 필요성이 증가되고 있다. 또한 현재 차량에서는 대쉬보드에 나타나는 각종 차량 상태를 파악하여 해당 차량의 이상 유무를 파악하도록 되어 있지만 구체적인 차량의 이상 상태를 운전자가 본질적으로 파악하기 어렵고, 주행 중에 있는 운전자에게 실시간으로 알려주는 장치들은 거의 없다. 그래서 운행 중에 발생되는 각종 이상에 대한 신속한 조치를 취할 수 없어 안전사고를 미연에 방지하기 어렵다. 본 논문에서는 멀티미디어서비스와 지리정보시스템 중심의 내비게이션의 한정된 서비스에서 소비자에게 보다 향상된 서비스 제공을 위한 자동차 관리 및 진단, 차량 편의 장치 제어 등의 기능을 추가하고 OBD-II표준을 이용하여 ECU로부터 차량 정보를 가져와 무선 네트워크 기술인 블루투스 통신을 이용하여 실시간으로 내비게이션에서 차량의 관리 및 진단이 유용한 내비게이션과 연동한 자동차 진단 프로그램을 제안하고자 한다.

• 한국지능시스템학회논문지
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• 제21권3호
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• pp.323-328
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• 2011

실제 시스템 적용에 있어서, 수중비행체(Underwater Flight Vehicle : UFV)의 자율제어(autonomous control)를 위한 3-D 장애물회피(obstacle avoidance) 시스템은 다음과 같은 문제점들을 가지고 있다. 즉, 소나(sonar)는 지역적 탐색영역 내에서 장애물의 거리(range)/방위(bearing) 정보를 제공하며, 자율수중운동체(Autonomous Underwater Vehicle : AUV) 관점에서 에너지 소비 및 음향학적 소음이 적은 시스템을 필요로 하며, 최대 피치 및 심도와 같은 UFV 운용 제약조건을 가진다. 나아가, 구조와 파라메터의 관점에 있어서 용이한 설계 절차를 요구한다. 이 문제를 해결하기 위해서 진화 전략(Evolution Strategy : ES) 및 퍼지논리 제어기(Fuzzy Logic Controller : FLC)를 이용하는 지능형 3-D 장애물회피 알고리즘이 제안되었다. 제안된 알고리즘의 성능을 검증하기 위해 UFV의 3-D 장애물회피가 수행되었다. 시뮬레이션 결과는 제안된 알고리즘이 실제 시스템에 존재하는 문제점들을 효과적으로 해결하고 있음을 보여준다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.57-62
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• 2004

This paper deals with a waypoint trajectory following problem for the tilt-rotor UAV under development in Korea (TR-KUAV). In this problem, dynamic model inversion based on the linearized model and Sigma-Phi neural network with adaptive weight update are involved to realize the waypoint following algorithm for the vehicle in the helicopter flight mode (nacelle angle=0 deg). This algorithms consists of two main parts: outer-loop system as a command generator and inner-loop system as stabilizing controller. In this waypoint following problem, the position information in the inertial axis is given to the outer-loop system. From this information, Attitude Command/Attitude Hold logic in the longitudinal channel and Rate Command/Attitude Hold logic in the lateral channel are realized in the inner-loop part of the overall structure of the waypoint following algorithm. The nonlinear simulation based on the TR-KUAV is carried out to evaluate the stability and performance of the algorithm. From the numerical simulation results, the algorithm shows very good tracking performance of passing the waypoints given. Especially, it is observed that ACAH/RCAH logic in the inner-loop has the satisfactory performance due to adaptive neural network in spite of the model error coming from the linear model based inversion.

• International Journal of Control, Automation, and Systems
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• 제3권2호
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• pp.217-224
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• 2005

Generally, the underwater flight vehicle (UFV) depth control system operates with the following problems: it is a multi-input multi-output (MIMO) system because the UFV contains both pitch and depth angle variables as well as multiple control planes, it requires robustness because of the possibility that it may encounter uncertainties such as parameter variations and disturbances, it requires a continuous control input because the system that has reduced power consumption and acoustic noise is more practical, and further, it has the speed dependency of controller parameters because the control forces of control planes depend on the operating speed. To solve these problems, an adaptive fuzzy sliding mode controller (AFSMC), which is based on the decomposition method using expert knowledge in the UFV depth control and utilizes a fuzzy basis function expansion (FBFE) and a proportional integral augmented sliding signal, is proposed. To verify the performance of the AFSMC, UFV depth control is performed. Simulation results show that the AFSMC solves all problems experienced in the UFV depth control system online.

• 약학회지
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• 제35권4호
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• pp.295-300
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• 1991

Ralationship between noradrenergic nervous system activity and luteinizing hormone releasing hormone(LHRH) content mediated by testosterone in hypothalamus was tested. Three groups of adult male animals were prepared; (1) Intact; (2) Castration+Vehicle (Cast+V); (3) Castration+Testosterone (Cast+T). Silastic capsule containing vehicle or testosterone was implanted into neck region of animals two weeks following castration. Norepinephrine content, alpha-adrenergic receptor binding characteristics using H$^{3}$-WB4101, and content of LHRH by LHRH RIA procedure were determined. Testosterone replacement to castrated male rats augmented the content of norepinephrine and LHRH. Testosterone replacement increased the alpha-adrenergic receptor density but did not change alpha-receptor affinity. The data from the present study suggest that increase in LHRH content by testosterone may be positively coupled to the activity of central noradrenergic nervous system.