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101.
本文证明了当2-(v,k,1)设计的自同构群G的基柱soc(G)=2F4(q2)时,Buekenhaut-Delandtsheer-Doyen猜想成立,即自同构群G的基柱为Ree群2F4(q2)的区本原2-(v,k,1)设计必为点本原的. 相似文献
102.
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104.
本文用“稳健设计”的观点,分别对OTL电路中点电压稳定性“系统择优”,“参数择优”及“容差择优”作出较为系统的介绍 相似文献
105.
Daniel G. Schwartz 《Fuzzy Sets and Systems》1985,17(2):153-165
This paper develops an interval-based approach to the concept of linguistic truth. A special-purpose interval logic is defined, and it is argued that, for many applications, this logic provides a potentially useful alternative to the conventional fuzzy logic.The key idea is to interpret the numerical truth value v(p) of a proposition p as a degree of belief in the logical certainty of p, in which case p is regarded as true, for example, if v(p) falls within a certain range, say, the interval [0.7, 1]. This leads to a logic which, although being only a special case of fuzzy logic, appears to be no less linguistically correct and at the same time offers definite advantages in terms of mathematical simplicity and computational speed.It is also shown that this same interval logic can be generalized to a lattice-based logic having the capacity to accommodate propositions p which employ fuzzy predicates of type 2. 相似文献
106.
在本文,我们证明了:若群G满足Sz(22m+1)≤G≤AutSz(22m+1)m≥1,且G作用在2-(v.k.1)设计上是线本原的,则G也是点本原的. 相似文献
107.
The properness of the efficient solution of the optimal problem with multicriteria has been independently defined by Kuhn and Tucker, Geoffrion, and Klinger. A theorem of Geoffrion describes the relation between Geoffrion's and Kuhn and Tucker's properness. In this paper, the dual part of the theorem is given, and some geometric approach is applied to derive the optimal conditions of proper efficient solutions and improper efficient solutions. 相似文献
108.
施绍裘 《宁波大学学报(理工版)》1988,(1)
采用传输线理论可以计算机械式UHF调谐器对应不同频率点的调谐电容量。在进行满足直线频率关系的调谐电容片形设计时,应当求出调谐电容量C_Τ与旋转角θ的显式函数关系。但对于分布参数的电路,这有一定的困难。本文采用数值计算方法完成了具有良好直线频率跟踪特性的调谐电容片形的设计,并由计算机自动绘出了片形。 相似文献
109.
B. D. Ripley 《Queueing Systems》1988,3(3):201-220
Simulation is a widely used methodology for queueing systems. Its superficial simplicity hides a number of pitfalls which are not all as well known as they should be. In particular simulation experiments need careful design and analysis as well as good presentations of the results. Even the elements of simulation such as the generation of arrival and service times have a chequered history with major problems lying undiscovered for 20 years. On the other hand, good simulation practice can offer much more than is commonly realized. 相似文献
110.
The primary aim of this paper is to demonstrate how the ‘design-of-experiments’ techniques which are successful in physical experiments could also be adapted to a numerical simulation code. As an example this technique is applied to a general finite difference code used for predicting three-dimensional turbulent recirculating flows. Here the equations for velocities and continuity are solved using the algorithm called SIMPLE, which stands for semi-implicit method for pressure-linked equations. Physical modelling of turbulence is taken care of by means of kinetic energy and turbulence dissipation rate equations. The objective is to optimize the underrelaxation factors of primary and secondary flow variables so that the number of iterations required for convergence is minimum. This is done by the orthogonal array technique (a particular type of design-of-experiment technique). The geometry considered for this purpose is that of a simple gas turbine can combustor and the study is restricted to the isothermal non-reacting condition. Tests are carried out on three different grid configurations. In each case the underrelaxation factor for velocities contributed most to speed up the rate of convergence. Also, for each grid configuration the underrelaxation factor settings for minimum iterations for convergence was found to be same. Hence it is proposed that when doing grid independence tests for any similar flow situation, all the underrelaxation factors could be optimized on coarse grids. 相似文献