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1.
Masao Nagai Yutaka Hirano Sachiko Yamanaka 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1997,27(5):357-370
An integrated control system of active rear wheel steering (4WS) and direct yaw moment control (DYC) is presented in this paper. Because of the tire nonlinearity that is mainly due to the saturation of cornering forces, vehicle handling performance is improved but limited to a certain extent only by steering control. Direct yaw moment control using braking and/or driving forces is effective not only in linear but also nonlinear ranges of tire friction circle. The proposed control system is a model matching controller which makes the vehicle follow the desired dynamic model by the state feedback of both yaw rate and side slip angle. Various computer simulations are carried out and show that vehicle handling performance is much improved by the integrated control system. 相似文献
2.
Takehiro Yamakoshi Peter Rolfe Yasuhiro Yamakoshi Hajime Hirose 《Transportation Research Part C: Emerging Technologies》2009,17(1):69-80
Automobile driving in monotonous situations such as driving for long periods and/or travelling a familiar route may cause the lowering of the driver’s awareness level or what we term here as a Driver’s Activation State (DAS), resulting in an increased risk of an accident. We propose here to develop means with which to create an in-car environment so as to allow active driving, hopefully thus avoiding potentially dangerous situations. In order ultimately to develop a validated activation method, we firstly set out to examine physiological variables, including cardiovascular parameters, during simulated monotonous driving. Subsequently, we investigated the derivation of a suitable DAS index. During the experiment, a momentary electrical test stimulus of 0.5 s duration was applied at a rate of approximately once per 10 min to the subject’s shoulder to evoke a physiological responses. In 11 healthy male volunteers we successfully monitored physiological variables during the experiment and found particular patterns in the beat-by-beat changes of blood pressure in response to the electrical test stimulus. This finding, explained by autonomic activity balance, suggests that the patterns may be used as an appropriate and practicable index relevant to the Driver’s Activation State. 相似文献
3.
Investigations into frictional resistance reduction by microbubbles were carried out using a two-dimensional channel. The
flow velocity and the amount of air injected were varied, and the frictional resistance reduction was measured. The frictional
resistance reduction increased with increasing mean void ratio. When the bubble diameter was changed, the influence on frictional
resistance reduction was negligible. The influence of bubble distribution near a wall was also investigated. Although it is
thought that the influence of microbubbles near a wall is large, further investigations are required.
Received: February 6, 2002 / Accepted: April 30, 2002
Acknowledgments. This research was supported by a special research program of Toyo University, SR239 Research Committee of the Shipbuilding
Research Association of Japan, and the Research Project on Smart Control of Turbulence. The authors express their sincere
gratitude for these supports.
Address correspondence to: H. Kato (kato@eng.toyo.ac.jp) 相似文献
4.
Shigeru Yamanaka Takayuki Sakanoue Toshikazu Yoshii Tatsuo Inoue . Fundamental Technological Laboratory THK Co. Ltd. Naniwa-ku Osaka Japan . Department of Energy Conversion Science Kyoto University Sakya-ku Kyoto Japan 《上海交通大学学报(英文版)》2000,(1)
IntroductionInelashcorhaersiblestrainaccompaniedbyslidingofcrystalsduetothermalandphasetransformationdilatationiswellknowntointensivelythethedistonionofworkpieceunderqUopching,andsomanynumericalsimulatonsll-7]havebeencAnedoutintheframeworkofmotallochermo-mechwhcsl1].Transformationplasticity(TP),anothekindofbeversiblestrain,isalsorecognizedasoneofdominantparwtersthechngthestr6ssanddistorton,andsomenumcricalcalculationaremadebytakingtheeffectintoconsideration.Figurelschematicallyillustraresthe… 相似文献
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6.
Yasuhiro Matsui Masami Kubota Shoko Oikawa 《International Journal of Automotive Technology》2018,19(1):77-83
The Japan New Car Assessment Program (J-NCAP) evaluates the performance of cars in terms of protection against whiplash injuries in rear-end collisions. In the test protocol, a simplified triangular acceleration is applied to the sled. This study clarifies whether biofidelic rear-impact dummy II (BioRID II) measurements obtained for simplified triangular acceleration reflect car-to-car rear-end impacts in real-world accidents in Japan. We conducted a car-to-car rear-end impact experiment and a simplified-triangular-acceleration sled test. Our results indicate that the time series of dummy responses were approximately consistent in the two test conditions. The neck injury criterion (NIC) and maximum acceleration of the head and T1 measured using the BioRID II dummy were similar in the car-to-car and sled experiments. This revealed that the J-NCAP test protocol using simplified triangular acceleration reflects the car-to-car rear-end impact experiment using Japanese cars, in terms of the NIC and maximum acceleration of the head and T1. 相似文献
7.
Yasuhiro Shiomi Toshio YoshiiRyuichi Kitamura 《Transportation Research Part B: Methodological》2011,45(9):1314-1330
This study investigates the mechanism of traffic breakdown and establishes a traffic flow model that precisely simulates the stochastic and dynamic processes of traffic flow at a bottleneck. The proposed model contains two models of stochastic processes associated with traffic flow dynamics: a model of platoon formation behind a bottleneck and a model of speed transitions within a platoon. After these proposed models are validated, they are applied to a simple one-way, one-lane expressway section containing a bottleneck, and the stochastic nature of traffic breakdown is demonstrated through theoretical exercises. 相似文献
8.
Mohamed Rehan Karim Nik Ibtishamiah Ibrahim Ahmad Abdullah Saifizul Hideo Yamanaka 《国际交通安全学会研究报告》2014
Vehicle overloading has been identified as one of the major contributors to road pavement damage in Malaysia. In this study, the weigh-in-motion (WIM) system has been used to function as a vehicle weight sorting tool to complement the exsiting static weigh bridge enforcement station. Data collected from the developed system is used to explore the effectiveness of using WIM system in terms of generating more accurate data for enforcement purposes and at the same time improving safety and reducing the number of vehicle weight violations on the roads. This study specifically focus on the effect of vehicle by-pass and static weigh station enforcement capability on the overall effectiveness of vehicle weight enforcement system in a developing country. Results from this study suggest that the WIM system will significantly enhance the effectiveness and efficiency of the current vehicle weight enforcement, thus generating substantial revenue that would greatly off-set the current road maintenance budget that comes from tax payers money. If there is substantial reduction in overloaded vehicles, the public will still gain through reduction in road maintenance budget, less accident risks involving heavy trucks, and lesser greenhouse gases (GHGs) emissions. 相似文献
9.
Yoshio Masuda Yasuhiro Yamanaka Yoshikazu Sasai 《Journal of Marine Science and Technology》2013,18(2):220-228
In moving-ship type CO2 ocean sequestration, liquid CO2 is discharged into a domain in a water column. Since the maximum CO2 concentration that is reached depends on the horizontal shape of the water column and the depths of release, it is very important to optimize these parameters for each injection site in order to minimize the biological impact. We conducted numerical experiments using an offline Oceanic General Circulation Model with a horizontal resolution of 0.1 degree × 0.1 degree. Experiments using a different horizontal site shape show that a site elongated in the meridional direction is effective to reduce the CO2 concentration. This is because CO2 has a tendency to be transported in a zonal direction. Optimization of the vertical distribution of CO2 injections is inherently determined by the balance of the following two factors; (1) dilution effect by eddy activity which decreases with depth, and the (2) predicted no effect concentration (PNEC), a criterion concentration causing no effect on biota, which increases with depth. Based on superposition of simulated CO2 concentration, we determined the optimized vertical distribution of CO2 injection which keeps the ratio of a simulated maximum CO2 concentration to PNEC constant. 相似文献
10.
This study focuses on the possibility that providing travelers with information on travel time distribution, along with the existing travel time information, might affect their decision making and enhance traffic control. As an initial step to confirm the effectiveness of travel time distribution information, we use a laboratory experiment to obtain panel data of route choices when information is provided. The rationality of the behavior of the respondents and the characteristics of the route choice are first analyzed by aggregation analysis and then statistically examined by specifying a mixed logit route choice model. As a result, it is revealed that both travel time information and maximum travel time information significantly affect route choice behavior when a penalty is imposed for late arrival. 相似文献