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刘建林 《上海交通大学学报(英文版)》2005,10(3):314-317
The definitions of generalized pseudoconvex,generalized quasiconvex and its strictly generalized convexity were presented for the static programming at locally star-shaped set using the concept of right-upper derivative and the concept of sublinear. The sufficient and necessary conditions of the static programming were derived in terms of a generalized Lemmain this paper. The results obtained are useful for the further study on the duality of static programming and cover many already known conditions. 相似文献
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ABSTRACTIn this article, we propose a new model called subjective-utility travel time budget (SU-TTB) model to capture travelers' risk-averse route choices. In the travel time budget (TTB) and mean-excess travel time (METT) model, a predefined confidence level is needed to capture the risk-aversion in route choice. Due to the day-to-day route travel time variations, the exact confidence level is hard to be predicted. With the SU-TTB model, we assume travelers' confidence level belongs to an interval that they may comply with in the route choice. The two main components of SU-TTB are the utility function and the TTB model. We can show that the SU-TTB can be reduced to the TTB and METT model with proper utility function for the confidence levels. We can also prove its equivalence with our recently proposed nonlinear-expectation route travel time (NERTT) model in some cases and give some new interpretation on the NERTT with this equivalence. Finally, we formulate the SU-TTB model as a variational inequality (VI) problem to model the risk-averse user equilibrium (RAUE), termed as generalized RAUE (GRAUE). The GRAUE is solved via a heuristic gradient projection algorithm, and the model and solution algorithm are demonstrated with the Braess's traffic network and the Nguyen and Dupuis's traffic network. 相似文献
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水声语音通信在海洋工程、海洋科考、水下搜救等领域具有广泛应用。与单边带通信、数字编码调制通信相比,调频水声语音通信具有实现简单方便、抗幅度衰落性能好的特点,但浅海水声信道具有的复杂多径效应及噪声严重影响其获得的语音音质,容易出现语音含混、语义难辨等问题。本文通过浅海不同距离、不同多径信道下的海试实验比较了采用非线性解调法和正交解调法的调频语音通信性能,并通过客观语音质量评估PESQ(Perceptual evaluation of speech quality)方法对调频水声语音通信音质进行量化评估。 相似文献
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A kind of new design method for two-degree-of-freedom(2DOF)PID regulator was presented,in which,a new global search heuristic--improved generalized extremal optimization(GEO)algorithm is applied to the parameter optimization design of 2DOF PID regulator.The simulated results show that very good dynamic response performance of both command tracking and disturbance rejection characteristics can be achieved simultaneously.At the same time,the comparisons of simulation results with the improved GA,the basic GEO and the improved GEO were given.From the comparisons,it is shown that the improved GEO algorithm is competitive in performance with the GA and basic GEO and is an attractive tool to be used in the design of two-degree-of-freedom PID regulator. 相似文献
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通过对己有各种单桩计算方法的研究总结,建立了单桩计算新理论。该理论与以往基于荷载传递法的单桩计算方法相比,做了如下改进:(1)桩侧与桩端采用广义荷载传递模型;(2)引入混凝土的Rusch模型以考虑高荷载水平作用下桩身混凝土的弹塑性性状;(3)耦合Mindlin解答以考虑桩侧摩阻力在桩端处产生的桩端位移。因此该单桩荷载-沉降关系计算方法在理论上更趋完善,使基于荷载传递法的多层地基中单桩荷载-沉降关系计算方法得到完善和统一。 相似文献
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应用广义拟余能原理研究流固耦合问题(英文) 总被引:1,自引:0,他引:1
水动力学与固体力学交叉的流固耦合理论是船舶与海洋工程结构响应分析与直接设计的重要工具.本文应用卷变积方法,按照广义力和广义位移之间的对应关系,将弹性动力学的基本方程卷乘上相应的虚量,然后积分,代数相加,并考虑到体积力和面积力均为伴生力,建立了非保守系统初值问题的两类变量的广义拟余能原理.应用广义拟余能原理研究流固耦合问题,分析了结构的动力响应,给出同时求解力类量和位移类量两类变量的计算方法. 相似文献