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901.
惠培 《西安交通大学学报(英文版)》1995,(2)
PHOSPHORYLATIONOFTHEMYELOIDZINCFINGERPROTEINMZF-1ISDIFFERENTIALLYREGULATEDDURINGMYELOPOIESISHuiPei;MariaR.Baer,PeterG.Bradfor... 相似文献
902.
王小民 《西安交通大学学报(英文版)》1995,(2)
MODULATIONOFAδ-ANDC-FIBEREVOKEDRESPONSESOFNOCICEPTIVENEURONSINTHESUPERFICIALANDTHEDEEPERDORSALHORNOFTHE MEDULLA:ROLEOFOPIOIDR... 相似文献
903.
Liwen Zhang Lixia Wei Guoliang Zhang J. Th.MDe Hosson Yuanliang Xia Fugang Wang . The State Key Laboratory for Materials Modification by Laser Ion Electron Beams . Material Engineering Department of Dalian University of Technology Dalian 《上海交通大学学报(英文版)》2000,(1)
IntroductionLaserTransformationhardeningtechniquehasbeensuccessfullyusedinindustryformanyyears.AlotsoftheoreticalworkshasbeendoneforheatflowduringthelasertfansformationhardeningofflatworkPieces["].Cyindricalbodiesarewidelyusedinindustrysuchaslocomotivecrankshaft,steelrollervalyeseat,enginecyinder.IftheschcesoftheseworkPiecesaretreatedbylasertheirwearresistancewiIIimProvealot.UptillnowmanyexPerimentalworkshasbeendoneforlasertransformationhardeningofcyindricalbodies,butfewtheoreticalworkshav… 相似文献
904.
THENEURONSDOUBLE-LABELLEDBYSEROTONINANDGLUTAMATE-IMMUNOREACTIVITYINMEDULLARYRAPHENUCLEIPROJECTINGTOTHECEREBELLARCORTEXOFTHEKI... 相似文献
905.
石冰 《西安交通大学学报(英文版)》1995,(2)
FFECTSOFNITRICOXIDESYNTHESISINHIBITIONWITHORWITHOUTNITRICOXIDEINHALATIONONRESPONSESTOSYSTEMICCOCAINEADMINISTRATIONINRATS.E.He... 相似文献
906.
907.
E. J. M. Hiensch N. Burgelman 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(9):1384-1404
The acting forces and resulting material degradation at the running surfaces of wheels and rail are determined by vehicle, track, interface and operational characteristics. To effectively manage the experienced wear, plastic deformation and crack development at wheels and rail, the interaction between vehicle and track demands a system approach both in maintenance and in design. This requires insight into the impact of train operational parameters on rail- and wheel degradation, in particular at switches and crossings due to the complex dynamic behaviour of a railway vehicle at a turnout. A parametric study was carried out by means of vehicle-track simulations within the VAMPIRE® multibody simulation software, performing a sensitivity analysis regarding operational factors and their impact on expected switch panel wear loading. Additionally, theoretical concepts were cross-checked with operational practices by means of a case study in response to a dramatic change in lateral rail wear development at specific switches in Dutch track. Data from train operation, track maintenance and track inspection were analysed, providing further insight into the operational dependencies. From the simulations performed in this study, it was found that switch rail lateral wear loading at the diverging route of a 1:9 type turnout is significantly influenced by the level of wheel–rail friction and to a lesser extent by the direction of travel (facing or trailing). The influence of other investigated parameters, being vehicle speed, traction, gauge widening and track layout is found to be small. Findings from the case study further confirm the simulation outcome. This research clearly demonstrates the contribution flange lubrication can have in preventing abnormal lateral wear at locations where the wheel–rail interface is heavily loaded. 相似文献
908.
Van Tan Vu Olivier Sename Luc Dugard Peter Gaspar 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(9):1405-1429
Rollover of heavy vehicle is an important road safety problem world-wide. Although rollovers are relatively rare events, they are usually deadly accidents when they occur. The roll stability loss is the main cause of rollover accidents in which heavy vehicles are involved. In order to improve the roll stability, most of modern heavy vehicles are equipped with passive anti-roll bars to reduce roll motion during cornering or riding on uneven roads. However these may be not sufficient to overcome critical situations. This paper introduces the active anti-roll bars made of four electronic servo-valve hydraulic actuators, which are modelled and integrated in a yaw-roll model of a single unit heavy vehicle. The control signal is the current entering the electronic servo-valve and the output is the force generated by the hydraulic actuator. The active control design is achieved solving a linear optimal control problem based on the linear quadratic regulator (LQR) approach. A comparison of several LQR controllers is provided to allow for tackling the considered multi-objective problems. Simulation results in frequency and time domains show that the use of two active anti-roll bars (front and rear axles) drastically improves the roll stability of the single unit heavy vehicle compared with the passive anti-roll bar. 相似文献
909.
In the conventional 2D-FFT based target detection method, all range-Doppler cells are computed by FFT (Fast Fourier Transform) and scanned by CA-CFAR (Cell-Averaging Constant False Alarm Rate) detection. This results in high computational complexity and long processing time. In this paper, we developed an automotive 24 GHz BSD (Blind Spot Detection) FMCW (Frequency Modulated Continuous Wave) radar with a low complexity target detection architecture based on a ROI (Region Of Interest) pre-processing scheme. In the real BSD zone, because the number of cars to be detected is limited, the designed method only extracts their velocities corresponding to the range ROIs in which real targets exist. Moreover, the presence probability of vehicles with the same range-bin but different velocities is very low. Thus, in the designed method, some Doppler ROIs cells with a high magnitude are only applied for CA-CFAR detection. This architecture can dramatically reduce the amount of data to be processed compared to that of the conventional 2D FFT based method, resulting in enhanced processing time. We developed a 24 GHz FMCW radar system composed a transceiver, antennas, and signal processing module. The designed algorithm was implemented in a tiny micro-processor of the signal processing module. By implementing our proposed algorithm in the developed 24 GHz FMCW radar system in an anechoic chamber and a real road, we verified that the range and velocity of a car occupying the BSD zone were detected. Compared to that of the conventional method, the reduction ratio of the total processing time was measured to be 52.4 %. 相似文献
910.
B. M. Duan Q. N. Wang J. N. Wang X. N. Li T. Ba 《International Journal of Automotive Technology》2017,18(2):335-344
This paper presents a calibration method of a rule-based energy management strategy designed for a plug-in hybrid electric vehicle, which aims to find the optimal set of control parameters to compromise within the conflicting calibration requirements (e.g. emissions and economy). A comprehensive evaluating indicator covering emissions and economy performance is constructed by the method of radar chart. Moreover, a radial basis functions (RBFs) neural network model is proposed to establish a precise model within the control parameters and the comprehensive evaluation indicator. The best set of control parameters under offline calibration is gained by the multi-island genetic algorithm. Finally, the offline calibration results are compared with the experimental results using a chassis dynamometer. The comparison results validate the effectiveness of the proposed offline calibrating approach, which is based on the radar chart method and the RBF neural network model on vehicle performance improvement and calibrating efficiency. 相似文献