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941.
A generalization of a well-known multiple objective linear fractional programming (MOLFP) problem, the multiple objective fractional programming (MOFP) problem, is formulated. A concept of multiple objective programming (MOP) problem corresponding to MOFP is introduced and some relations between those problems are examined. Based on these results, a compromise procedure for MOLFP problem is proposed. A numerical example is given to show how the procedure works.  相似文献   
942.
This paper is concerned with the development of a new high‐order finite volume method for the numerical simulation of highly convective unsteady incompressible flows on non‐uniform grids. Specifically, both a high‐order fluxes integration and the implicit deconvolution of the volume‐averaged field are considered. This way, the numerical solution effectively stands for a fourth‐order approximation of the point‐wise one. Moreover, the procedure is developed in the framework of a projection method for the pressure–velocity decoupling, while originally deriving proper high‐order intermediate boundary conditions. The entire numerical procedure is discussed in detail, giving particular attention to the consistent discretization of the deconvolution operation. The present method is also cast in the framework of approximate deconvolution modelling for large‐eddy simulation. The overall high accuracy of the method, both in time and space, is demonstrated. Finally, as a model of real flow computation, a two‐dimensional time‐evolving mixing layer is simulated, with and without sub‐grid scales modelling. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
943.
小波分式滤波器   总被引:3,自引:0,他引:3  
匡正  李云晖  崔明根 《计算数学》1998,20(4):353-358
1.引言用小波处理实际问题时,对称性具有重要的意义.如果小波不具有对称性,则在信号重构时可能导致失真.我们知道,用多项式滤波器构造的正交小波不具有对称性,这是一个重要的缺欠.本文讨论了分式滤波器,它作为多项式滤波器的最自然的推广和进展,且包含了B样条小波滤波器,可随意构造出对称性小波函数,对实际应用提供了有意义的构造性方法.在小波计算中,为了回避hllrl*r逆变换,人们通常喜欢用Mdl时算法山,即对尺度函数方程为造迭代格式为了得到迭代收敛(n。、v)条件,通常把滤波器其中以及时,迭代格式(2)逐点收敛于尺…  相似文献   
944.
截断半径变化对汽液界面参数和分维数的影响   总被引:2,自引:1,他引:1  
本文在分形理论基础上,采用分子动力学模拟方法研究了在平衡状态下的汽液界面参数,得了界面区内的密度、 温度、压力张量、表面张力和分维数的分布。研究表明,利用分形理论可以较好的反映汽液界面的特性。势函数的截断半 径对汽液界面参数和分维数的模拟值存在影响。  相似文献   
945.
The fractional spin of a system with Chern–Simons (CS) term coupled to a polaron at the quantum level is studied. The Faddeev–Senjanovic (FS) scheme for path-integral quantization of constrained Hamiltonian systems is applied. The quantal conserved angular momentum and the fractional spin at the quantum level of this system are presented based on the quantal Noether theorem. The fractional spin is also presented for the system with Maxwell kinetic term.  相似文献   
946.
The property of fractional spin of the system with Chern–Simons (CS) term coupled to polaron at the quantum level is studied. According to the rule of path integral quantization for constrained Hamiltonian system in Faddeev–Senjanovic (FS) scheme, this system is quantized. Based on the quantal Noether theorem, the quantal conserved angular momentum and the fractional spin at the quantum level of this system is presented. The fractional spin is also presented in the system including Maxwell kinetic term.  相似文献   
947.
利用GC-MS分别检测分级冷凝装置和常规冷凝装置制备的核桃壳生物油,对比常规冷凝生物油与分级冷凝多品级生物油有机组分的相对峰面积,发现分级冷凝对组分富集有较大影响,其中,乙酸在第四级生物油内相对峰面积从5.38%上升至9.44%;愈创木酚在第二级内从3.46%上升至6.23%;紫丁香醇在第一级内从1.48%上升至4.44%;异丁香酚在第一级内从5.52%上升至17.84%。经过75 d、15℃恒温恒湿储存后分级冷凝生物油水分增加,分别增加了1.58%、1.88%、1.80%、2.43%;脂肪类有机物峰面积减小;酚类有机物峰面积增大。第一、二级生物油内小分子有机物含量较少,老化反应强度较低;第三、四级生物油内小分子有机物含量较多,老化反应强度较高。根据GC-MS检测结果将有机物分类,统计各类有机物在储存前后的含量变化,分析储存过程中各类有机物发生的老化反应种类以及反应强度。  相似文献   
948.
This paper considers the consensus control problem of multi-agent systems (MAS) with distributed parameter models. Based on the framework of network topologies, a second-order PI-type iterative learning control (ILC) protocol with initial state learning is proposed by using the nearest neighbor knowledge. A discrete system for proposed ILC is established, and the consensus control problem is then converted to a stability problem for such a discrete system. Furthermore, by using generalized Gronwall inequality, a sufficient condition for the convergence of the consensus errors between any two agents is obtained. Finally, the validity of the proposed method is verified by two numerical examples.  相似文献   
949.
The pivotal aim of the present study is to employ fractional natural decomposition method (FNDM) to find the solution for a nonlinear system arising in thermoelasticity. The considered coupled system is generalised many physical phenomena associated with the material with elastic characters and its temperature and also which is called a Cauchy problem. We consider the coupled system by incorporating the Caputo fractional operator and investigate three distinct cases for different initial values to illustrate the applicability and efficiency of the FNDM. With respect to fractional order, we capture the behaviour of the achieved solution cited in three different cases and exemplified with the aid of 2D and 3D plots for the particular value of the parameters in the model. Moreover, some interesting behaviours of the projected model are confirms the prominence of the employed fractional operator while analysing the nonlinear coupled equations exemplifying real-world problems and also shows the capability of the considered algorithm.  相似文献   
950.
We establish lower and upper bounds for the small ball probability of a centered Gaussian process(X(t)) t[0,1] N under Hölder-type norms as well as upper bounds for some more general functionals. This extends recently established results for the uniform norm. In addition, our proof of the lower bound is considerably simpler. In the special caseN=1 we establish precise estimates under a wider class of norms including in particular the Besov norms.  相似文献   
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