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511.
This paper describes a comparative study between full scale measurements recorded on a fast patrol boat encountering heavy winter seas, south of the Isle of Wight and theoretical predictions accounting for the slamming behaviour of the flexible hull. A hydroelastic approach is adopted and satisfactory agreement between measured and predicted responses demonstrated. 相似文献
512.
Ship managers have been slow in their response to using information technology (IT) in spite of the dynamic environment encouraging technological support for a number of critical tasks. The reason is in part the conservatism of the shipping industry, but the main reason seems to be the poor quality of systems provided, creating a credibility gap and usage reluctance. This paper suggests five principles for the development of 'user seductive' systems and illustrates their successful use in a number of case histories of management support systems development. 相似文献
513.
P. A. Caridis 《Marine Structures》1988,1(2)
Results from a series of studies on stiffened plates under axial compression are presented in this paper. The large-deflection elasto-plastic behaviour of each panel component is described by the von Karman equations, thus enabling the lateral-torsional buckling of the stiffener to be modelled in a rigorous manner. Material nonlinearity is represented using the von Mises yield criterion in conjunction with the Prandtl-Reuss flow rule. Results are presented in the form of average stress-strain curves which are used to generate maximum strength curves for the stiffener and plate. 相似文献
514.
515.
A.G. Thompson P.M. Chaplin 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1996,25(3):185-202
For a simple vehicle active suspension system complete optimality and zero steady state body displacements may be achieved if the axle and body accelerations, and other easily measured quantities, are included in the performance index. Apart from not requiring an observer, this also allows the optimal feedback gains to be determined for an arbitrary body spring rate. In a theoretical example, model parameters matching those of an experimental test rig are employed. The results of computer simulations, with and without an electrohydraulic servovalve and actuator, are compared to demonstrate the effects of inner loop gain on force control. Aspects of the system behaviour including lockup are commented upon. 相似文献
516.
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518.
Adaptive Throttle Control for Speed Tracking 总被引:5,自引:0,他引:5
Z. Xu P. Ioannou 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1994,23(1):293-306
Electronic throttle control is an important part of every advanced vehicle control system. In this paper we design an adaptive control scheme for electronic throttle that achieves good tracking of arbitrary constant speed commands in the presence of unknown disturbances. The design is based on a simplified linear vehicle model which is derived from a validated nonlinear one. The designed control scheme is simulated using the validated full order nonlinear vehicle model and tested on an actual vehicle. The simulation and vehicle test results are included in this paper to show the performance of the controller. Due to the learning capability of the adaptive control scheme, changes in the vehicle dynamics do not affect the performance of the controller in any significant manner. 相似文献
519.
本文分析了传统二冲发动机的优缺点,全面阐述了对现代二冲程发动机的要求和各方面的改进设想,对今后设计新的二冲程发动机有一定的指导价值。 相似文献
520.
Mufu Yan Jihong Yan Zhiru Liu . School of Materials Science Engineering Harbin Institute of Technology Harbin P. R.China . Department of Automation Tsinghua University Beijing P. R. China 《上海交通大学学报(英文版)》2000,(1)
IntroductionTheworkonthermochemica1treatInntswithasadditiOnswasshmulatOdbybasicresearchinl982inChinall].SignilicantProgfesshasbeenmadedurillthepastdecadeinthefield.TheresultsshowthatontheonehandtheREe1emedscanacceleratethedecomPositionofthemediumandactiVatethecarburizedschceofsteelsandthusenhancethecoefficientofcarbontransfer(D").OntheotherhandatelevatedtemPeratUreREelements,althoughtheyhavemuchbiggeratOmicsizesthaniron,couddiffuseintobasedalloystOasignilicamdepth.MoreifllPortantiXtheP… 相似文献