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831.
CD_4~(+)EFFECTORCELLSDEFAULTTOTHETH2PATHWAYININTERFERONγ-DEFICIENTMICEINFECTEDWITH LEISHMANIA MAJORWangZhi'en;StevenL.Reiner,Z... 相似文献
832.
石冰 《西安交通大学学报(英文版)》1995,(2)
NITRICOXIDESYNTHESISINHIBITIONENHANCESBUPIVACAINECARDIOTOXICITYJ.E.Heavner,ShiBing;M.Pitkanen(DepartmentofAnesthesiology,Texa... 相似文献
833.
M.M. Elmadany 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1987,16(5):297-312
The purpose of this paper is to develop a procedure based on covariance analysis and nonlinear programming techniques which can be used for the parameter selection of optimum truck suspensions. The procedure is applied to explore the differences in parameter selection caused by the changes in the frequency content of the road input or by changes in the criteria for optimization. The equations of motion for a tractor-semitrailer truck are cast in state space form. The road excitations are represented by the output of a white noise excited shaping filter taking into consideration the time delays between the different vehicle axles. Shape filters to represent human perception of vibration in both the vertical and longitudinal directions in the time domain are presented and realized in terms of state variables. The suspension parameters of the road-vehicle-human body system are optimized using a direct search algorithm. 相似文献
834.
835.
M. Mitschke 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1975,4(1):43-54
Control systems consisting of a guideway fixed on the road and a controller built in the motor-vehicle can substitute the vehicle driver. In this paper stability of such systems is discussed for the case of low speed vehicles. In this case it is possible to simplify the model by neglecting some dynamic vehicle properties.
Der Fahrer im Kraftfahrzeug kann durch eine Leitlinie in der Fahrbahn und durch einen Regler im Kraftfahrzeug ersetzt werden. Fur solch ein System werden die Stabilitatsbedingungen diskutiert, und zwar fur Kraftfahrzeuge, die langsam fahren. Dabei konnen die dynamischen Eigenschaften vernachlassigt werden. 相似文献
Der Fahrer im Kraftfahrzeug kann durch eine Leitlinie in der Fahrbahn und durch einen Regler im Kraftfahrzeug ersetzt werden. Fur solch ein System werden die Stabilitatsbedingungen diskutiert, und zwar fur Kraftfahrzeuge, die langsam fahren. Dabei konnen die dynamischen Eigenschaften vernachlassigt werden. 相似文献
836.
837.
Two problems concerning the use of aerial photographs for conducting traffic studies in urban areas are considered in this paper: (1) Suitable procedures requiring simple equipment and methods and the appropriate formulae for determining the traffic characteristics of density, volume, traffic count, speed, composition; (2) Problems relating to flight planning for traffic surveys from the points of view of duration of photography and the scale of the photography from considerations of the reliability of the determined traffic characteristics, vehicle identification, and also economy. The conclusions concerning the flight planning were applied in a test flight from which traffic data were determined as illustrated in a sample calculation. 相似文献
838.
839.
M. J. Smith 《Transportation Research Part B: Methodological》1981,15(6):453-462
We consider a network with interactions and capacity constraints at each junction. We give conditions on the interactions and constraints which, if satisfied at each separate junction, ensure that any feasible assignment problem has an equilibrium solution. Two illustrative examples are provided; the first arises naturally and does not satisfy our conditions, while the second does satisfy our conditions but is somewhat unnatural. 相似文献
840.
M. J. H. Mogridge 《Transportation》1979,8(1):51-63
This report describes an application of continuous spatial models to freight movements in Greater London. Continuous spatial models are fitted to data on the densities of generation and attraction of the freight assuming that the density is dependent on the distance from the centre of the area. The fit is measured using regression analysis and the results are examined. The graphs of the densities against the distance from the centre suggest an exponential relationship, and Clark's model is fitted to the data. The model fits fairly well to the data on densities for most groups of commodities. The correlation between the density and the distance is stronger for attraction than for generation in most groups of commodities. 相似文献