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131.
132.
房志宇 《西安交通大学学报(英文版)》1995,(2)
INVITROGLYCATIONOFHEMOGLOBIN(HB):CHOOSINGTHEAPPROPRIATEMODELFangZhiyu;R.R.Little,H.M.Wiedmeyer,D.E.Goldstein(DepartmentofChil... 相似文献
133.
Characteristics of Guided-Steering Railway Trucks 总被引:1,自引:0,他引:1
R. E. Smith R. J. Anderson 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1988,17(1):1-36
The dynamic characteristics of guided-steering railway trucks are described both in a general sense and in terms of a specific design. Stability margins and curving performance have been predicted and are compared for both conventional and steered vehicles. It is shown that guided-steering trucks exhibit modes of instability which, although surmountable by proper design, are not found in conventional trucks. In particular, a low conicity, divergent, leading truck instability is described together with a companion high conicity, divergent trailing truck instability. Curving and dynamic performance for steered vehicles is shown to have the potential of being far superior to that of comparable conventional vehicles. Factors influencing the design of steered rail vehicles are presented and discussed. 相似文献
134.
To plan new bus routes in suburban areas, expected bus running times on these routes are needed. Using most readily available relevant variables, a regression model is developed for estimating bus running times. The model is conceptually reasonable and it was tested using data other than that used for estimation. 相似文献
135.
J. R. Ellis P. L. Read 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1976,5(4):205-219
The paper describes the development, operation and some of the results obtained from a simulation of the steering behaviour of the double bottom articulated vehicle, in particular the effects that arise when certain axles are locked. 相似文献
136.
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138.
S. S. Vallurupalli R. V. Dukkipati M. O. M. Osman 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1996,26(3):161-196
This paper presents a discrete adaptive control approach for an active suspension. The study involves formulation of an active suspension as a digital controller problem involving the time delays. A nonlinear time varying (NTV), single input single output (SISO) suspension model is considered for the analysis. A discrete model reference adaptive control (DMRAC) approach with recursive least square (RLS) estimation is used to form the controller. The controller is designed to maintain the static equilibrium irrespective of dynamic load variations as a disturbance force on the model. Simulation results for deterministic and stochastic inputs are presented to substantiate the approach. Results indicate good performance of adaptive controller even for large dynamic variations of the model and has the potential for a successful hardware implementation. 相似文献
139.
James R. Jones Lu Qu Kenneth L. Casavant Won W. Koo 《Maritime Policy and Management》1995,22(1):63-80
A mathematical spatial programming model developed to analyse changes in international and hinterland commodity flows through a regional port system is applied to wheat shipments through the U.S. Pacific Northwest port system. Two scenarios, one focusing on a Chinese quarantine on wheat shipments from the Pacific Northwest and the other on possible closure of barge transportation on the Columbia-Snake River, illustrate the capacity of the model to evaluate the impacts of international and hinterland shocks on the regional port system. 相似文献
140.
Mary R. Brooks 《Maritime Policy and Management》1983,10(2):77-85
This paper focuses on the potential effects the UNCTAD Liner Code of Conduct's provisions for cargo reservation on consumers of shipping services, with special reference to Canada. It is clear that as more nations enact flag-discriminating legislation then fewer choices amongest distribution options will exist for the consumer. This will involve nations like Canada in a fundamental reassessment of their current shipping policy, since the rationale of 'free market' competition will no longer be valid: carrier and services options will be curtailed. In the light of this, Canada will be forced to examine the concepts of 'free trade' and 'private sector enterptise' and develope a considered response that protects the consumer interest. 相似文献