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141.
Simulation Approach to the Effect of the Ratio Changing Speed of a Metal V-Belt CVT on the Vehicle Response 总被引:10,自引:0,他引:10
T. Ide A. Udagawa R. Kataoka 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1995,24(4):377-388
In regard to the belt and pulley system of a metal V-belt CVT, the characteristics of the ratio changing speed is obtained by experiments. It is summarized in a practical and simple experimental equation. By using this equation a simulation model is developed to analyze the response of a vehicle with a metal V-belt CVT to a rapid pulley ratio change. The simulation results are in reasonable agreements with experimental results. 相似文献
142.
143.
A.G. Thompson B.R. Davis 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1992,21(1):19-37
By the incorporation of frequency-shaping into the linear quadratic methods used in active suspension design it is possible to achieve improvements in both body frequency response and road-holding. The use of a PID filter for this purpose also leads to robustness of the system to disturbance forces. Zero steady-state deflections are achieved for applied body loads by the integral action with excellent attenuation of the transient response. The resulting system consists of a hydraulic actuator in parallel with a body spring of arbitrary stiffness and is optimal with equivalent full state feedback. 相似文献
144.
145.
146.
A. Karageorgis Ch. Anagnostou A. Sioulas G. Chronis E. Papathanassiou 《Journal of Marine Systems》1998,16(3-4)
This work aims at studying the geochemistry and mineralogy of Milos bay surface sediments. The bay forms an enclosed marine area, supplied totally by volcanic formations. Totally 16 samples were subjected to sedimentological (grain size), mineralogical (microscope examination and X-ray diffraction of the bulk sample and the pelitic fraction), and geochemical analyses (X-ray fluorescence in the pelitic fraction). Also the carbonate content was determined. Sediments were sandy with a high carbonate content (14–58%). The dominant minerals recognized in the pelitic fraction were smectite, kaolinite and illite, followed by chlorite, quartz, calcite, Mg-calcite and feldspars. In general, element concentrations appeared to be within the normal range, except Pb and Zn, which exhibited relatively high values. The Index of Geoaccumulation Igeo was computed, in order to investigate a possible enrichment of the surface sediments in metals. The analysis revealed again high values of Igeo class for both Pb and Zn. A careful study of the area, in relation to the quality of the catchment basins petrology, lead to a non-anthropogenic origin of these high concentrations. The enrichment of the surface sediments in Pb and Zn is attributed to the weathering of several mineral deposits, pyroclastic rocks and lavas, covering almost all Milos vicinity. A study of the geochemical data correlation coefficient matrix revealed three major groups of elements: (i) the elements of detrital origin represented by Si, Al, K and a part of the metals; (ii) the carbonates group; and (iii) a Fe–Mn oxyhydroxides–oxides group, which attracts a part of Pb, Cr and Ni. 相似文献
147.
The background and the literature in liner fleet scheduling is reviewed and the objectives and assumptions of our approach are explained. We develop a detailed and realistic model for the estimation of the operating costs of liner ships on various routes, and present a linear programming formulation for the liner fleet deployment problem. Independent approaches for fixing both the service frequencies in the different routes and the speeds of the ships, are presented. 相似文献
148.
This work presents an experiment on the relationships between subjective and objective evaluations of vehicle handling. Ten
cars were examined objectively in several open-loop driving dynamics manoeuvres and subjectively by test persons in typical
traffic situations. Results are extracted from a stationary test (the Slowly Increasing Steer Test), and a dynamical test
(the Frequency Response Test). The subjective measurements are obtained from drivers on a rural road course via a questionnaire,
which was developed to separately investigate the quantity level perception, the so-called “Niveau”, and the more qualitative
“Liking”. These subjective “measurements” are embedded into a two-channel definition of “Steering Comfort” as a genus for
“Steering Discomfort” and “Character”. The article concentrates on developing a statistical method for the consideration of
correlations amongst the subjective/objective data. In doing so, the variance in example subjective Niveau ratings can be
significantly explained by several objective quantities. Indicators for co-domains of validated discomfort characteristics
and hints for endeavouring character Liking ranges are detected. 相似文献
149.
Dimitrios A. Tsamboulas Anastasios Nikoleris 《Transportation Research Part A: Policy and Practice》2008,42(10):1274-1282
There are cases when passengers are willing to pay a premium to reduce the travel time, in particular when the trip has to be made. This paper aims to provide insight into factors that determine passengers’ willingness to pay to reduce travel time for their ground access to an airport. A methodology is developed that comprises two steps: the identification of the passengers with zero willingness to pay and from the rest the estimation of the additional price they are willing to pay to reduce their travel time. For the first step a Probit model was formulated and for the second a linear regression model. To this purpose, data has been collected employing stated preference from passengers at the Athens International Airport. It has been found that a high percentage of passengers have zero willingness to pay, and of the remaining ones those using public transport have a significant willingness to pay to reduce access travel time. The methodology and the models are structured in such a way that their transferability to any airport environment is possible, thus providing a useful tool for decisions relating to airport ground access measures. 相似文献
150.
A.T.Kearney 《上海汽车》2018,(1)
正关于自动驾驶发展进程的预测,业内普遍认同的观点是:自动驾驶汽车将在2025年前后开始呈现爆发式增长;到2035年,人类社会道路上行驶的车辆将有50%实现自动驾驶,届时自动驾驶整车及相关设备、应用的收入规模总计将超过5 000亿美元。1产品定位——从简单的交通工具转变为移动多用途空间无人驾驶首先转变的将是汽车产品自身的定位。在自动驾驶技术成为主流的时代,系统基本上 相似文献