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491.
H. Ouwerkerk Ramachandra Rao Guntur 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1972,1(2):67-88
In this paper, available information about anti-skid devices is reviewed with the specific purpose of bringing out the importance of skid prediction. Then the merits and demerits of three methods of prediction are studied. 相似文献
492.
A simultaneous vehicle scheduling and bus garage location and sizing optimization is described. The methodology's importance lies in its treating garage locations and sizes and vehicle schedules as dynamic. In other bus garage planning methodologies, vehicle schedules are assumed fixed. 相似文献
493.
Russell H. Owen James E. Bernard 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1982,11(5):251-265
This paper presents a study of the directional dynamics of large industrial tractors. These vehicles have special properties which make their dynamics interesting, including soft rear tires, large yaw moments of inertia and low or negative understeer gradients.
A linear yaw plane model was used for the analysis. The lateral compliance of the tires was included via a simplified version of the stretched-string model. Measurements were performed in support of the modeling effort, including inertial parameters, understeer gradient and transient response. A comparison between calculations and test results indicated that lateral compliance was an important influence on the transient response of these vehicles. 相似文献
A linear yaw plane model was used for the analysis. The lateral compliance of the tires was included via a simplified version of the stretched-string model. Measurements were performed in support of the modeling effort, including inertial parameters, understeer gradient and transient response. A comparison between calculations and test results indicated that lateral compliance was an important influence on the transient response of these vehicles. 相似文献
494.
495.
Xu X.-N.Li Y.-N.Li H.Song Z.-D.Liu D.-C. 《铁道工程学报》2018,(11):82-86
Research purposes: CTCS-3 train control system is adopted in Chinese high-speed railway with speed of 300 km/h or higher. It is based on track circuit to check train occupancy and adopt quasi-moving block. In recent years, rapid development of national economy has put forward higher requirements for the capacity of high-speed railway. As a higher level train control system, CTCS-4 train control system can realize virtual block or moving block, and further shorten headway, but it is still in the stage of theoretical research. So this paper aims to analyze the characteristics of high-speed railway, and to propose a scheme for the implementation of CTCS-4 train control system based on track circuit fusion. Research conclusions:(1)When the wireless communication between vehicle and ground is interrupted, transport efficiency of CTCS-4 train control system can not meet the transport demand of high-speed railway.(2)CTCS-4 train control system should have the CTCS-2 backup function, which can make non-communication trains run normally and ensure the transport efficiency.(3)CTCS-4 train control system should integrate track circuit information, which can make RBC obtain position information of non-communication trains, improve the availability of the system and avoid complicated operational rules.(4)Due to complexity of high-speed railway and change of existing equipment, virtual block can be used in early stage of CTCS-4 train control system.(5)The research results can provide some references for CTCS-4 train control system in high-speed railway. © 2018, Editorial Department of Journal of Railway Engineering Society. All right reserved. 相似文献
496.
Fu H.-L.Hu C.-C.Lin R.Huang Z.Zhang J.-B.Shi Y. 《铁道工程学报》2018,(11):48-54
Research purposes: In the construction process of curved shield tunnels, the force of excavation face is extremely complex and the stability is difficult to control, so it is very likely that the thrust of the jack will cause uplift of the soil in front because of passive failure. Taking the sand strata as an example, this paper established a combination model of "inverted ladder-wedge prism" to reveal that the soil in front of the excavation face of curved shield tunnels uplifts up because of passive failure based on the silo theory and limit equilibrium method, and deduced the calculation method of passive limited supporting force for curved tunnels. Then, we confirmed the accuracy and reliability of this model and calculation method through programing and simulating. Research conclusions:(1) The passive limited supporting force increases with the increase of buried depth and internal friction angle, and the growth rate gradually increases. (2) When the radius of the line is less than 200 m and the internal friction angle is more than 25 degrees, the passive limited supporting force is very sensitive to the curvature radius, and when the radius is more than 800 m, the passive limited supporting force is almost no difference with straight tunnels. (3) The numerical results indicate that the numerical solution is consistent with the theoretical solution and the difference is quite small. (4) The research results can provide theoretical basis for determining the passive limited supporting force in the constructions of similar curved shield tunnels especially small turn radius shield tunnels. © 2018, Editorial Department of Journal of Railway Engineering Society. All right reserved. 相似文献
497.
房志宇 《西安交通大学学报(英文版)》1995,(2)
THEEFFECTOFVITAMINCINTAKEONGLYCOHEMOGLOBINMEASUREMENTSFangZhiyu;SuMing,R.R.Little,H.M.Wiedmeyer,D.E.Goldstein(DepartmentofChi... 相似文献
498.
卜昕 《西安交通大学学报(英文版)》1995,(2)
NOVELPHOSPHORYLATIONSITESOFEUKARYOTICINITIATIONFACTOR-4EANDEVIDENCETHATPHOSPHORYLATIONSTABILIZESINTERACTIONSOFTHEP~25ANDP~220... 相似文献
499.
Traffic safety,usability and streetscape effects of new design principles for major urban roads 总被引:1,自引:0,他引:1
Hartmut H. Topp 《Transportation》1989,16(4):297-310
An important aspect of area-wide traffic calming concepts is the integration of major urban roads, because 70 to 80 percent of all urban accidents occur on major roads. Traffic calming which is primarily based on the locational shift to such main thoroughfares is socially injust, because — in spite of all disturbances on those streets — about one quarter of the urban population live there. Social justice can only be somewhat achieved if the expenditures for traffic calming and streetscaping are not used — as today is most common — for accumulating the advantages in the low traffic side streets, but aimed at a partial balance and compensation for the strains caused by car traffic on the major streets. Some compensatory measures and new design principles will be discussed. Backgrounds are the experience in six German model cities of area-wide traffic calming, several research projects and the discussion about new guidelines for major urban roads. Where traffic and environmental burdens focus, the concentration concept should be extended by compensatory measures. That is the state of discussion in Germany examplified by nine topics.This is an edited version of a speech presented by the author at the International Conference Living and Moving in Cities in Paris, January 1990. 相似文献
500.
Safety mechanism is required for an automotive battery pack to prevent thermal failure which could lead to catastrophic events. Passively cooled battery packs can prevent thermal failure by conducting adaptive control of battery power without any external cooling device. The key to this power control is how to secure battery safety while minimizing energy loss. This paper proposes a novel, adaptive power control strategy for automotive passive-cooling battery packs. Four different cases with electrochemical battery model are simulated and compared to each other according to a city driving profile. Driving simulation result confirmed that the present power control algorithm is an effective solution for preventing thermal failure along with improving energy efficiency of automotive battery packs. 相似文献