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1.
Let F(S) be the free algebra of type (,∨,→) generated by the non_empty set S, it is proved that the logical equivalent relation defined by means of R 0_semantics is a congruence relation on F(S) and the corresponding quotient algebra is said to be the R 0_semantic Lindenbaum algebra. Taking R 0_semantic Lindenbaum algebra as a prototype, the concepts of implicational lattices and regular implicational lattices which are generalizations of the concept of Boolean algebras are introduced. Besides, the concept of fuzzy implicational spaces is introduced and the representation theorem of regular implicational lattices is obtained by means of fuzzy implicational spaces. In case of Boolean algebras, the corresponding fuzzy implicational spaces are zero_dimensional compact Hausdorff spaces and herefrom it is proved that the famous Stone's representation theorem of Boolean algebras is a corollary of the representation theorem of regular implicational lattices.  相似文献   

2.
A new approach for the derivation of the principal invariants of the stretch tensor with respect to the right Cauchy-Green tensor is presented in this paper. According to the definition of the derivation of tensor function, the three first-order derivatives for the principal invariants of the stretch tensor are obtained through derivation directly to the right Cauchy-Green tensor by incremental method. Then the three second-order derivatives are yielded by the derivation to the right Cauchy-Green strain tensor directly. Furthermore, an explicit expression of the tangent modulus of the general Varga material is given as an example.  相似文献   

3.
LU Jun 《自然科学进展》2007,17(2):144-149
The rigorous solutions of the stationary Schr?dinger equation for hydrogen atom are solved with the wave-mechanics method within the framework of the quantum phase-space representation established by Torres-Vega and Frederick. The “Fourier-like” projection transformations of wave function from the phase space to position and momentum spaces are extended to three-dimensional systems. The eigenfunctions in general position and momentum spaces could be obtained through the transformations from eigenfunction in the phase space.  相似文献   

4.
The rigorous solutions of the stationary Schrodinger equation for hydrogen atom are solved with the wave-mechanics method within the framework of the quantum phase-space representation established by Torres-Vega and Frederick. The "Fourier-like" projection transformations of wave function from the phase space to position and momentum spaces are extended to three-dimensional systems. The eigenfunctions in general position and momentum spaces could be obtained through the transformations from eigenfunction in the phase space.  相似文献   

5.
The main results are as follows: ( i ) For the number of chord diagrams of order n, an exact formula is given. ( ii ) For the number of spine diagrams of order n, the upper and lower bounds are obtained. These bounds show that the estimation is asymptotically the best. As a byproduct, an upper bound is obtained, for the dimension of Vassiliev knot invariants of order n, that is, 1/2 ( n -1)! for any n≥3, and 1/2( n - 1)! - 1/2( n - 2)! for bigger n . Our upper bound is based on the work of Chmutov and Duzhin and is an improvement of their bound ( n - 1)! . For n = 3, and 4,1/2( n - 1)! is already the best.  相似文献   

6.
The spectral moments are the important algebraic invariants of graphs.In this paper,on the basis of definitions of tricyclic graphs,base and the sequence of spectral moments,respectively,we study tricyclic graphs with given bases on the lexicographical order of the spectral moments sequence,and find the last and the first graphs.The results is very helpful for studying all tricyclic graphs ordering by spectral moments.  相似文献   

7.
Weighted occupation time processes associated with the super-Brownian motions on hyperbolic spaces are investigated. Longtime behavior and a central limit type theorem for the processes are obtained. For all dimension d≥2, the right normings for two fluctuations are t and t1/2 , and the limit results are the Riemannian measure and some centered Gaussian random measure, respectively.  相似文献   

8.
A theoretical model of collisional quantum interference ( CQI) is developed in a diatom-diatom system based on the first-order Born approximation of time-dependent perturbation theory and the multipolar interaction potential. The transition cross section is obtained. The relations between the differential and integral interference angles are discussed. The key factors on the determination of the differential and integral interference angles are obtained. The changing tendency of the interference angles with the experimental temperatures is obtained.  相似文献   

9.
Weighted occupation time processes associated with the super-Brownian motions on hyperbolic spaces are investigated. Longtime behavior and a central limit type theorem for the processes are obtained. For all dimension d≥2, the right normings for two fluctuations are t and t1/2, and the limit results are the Riemannian measure and some centered Gaussian random measure, respectively.  相似文献   

10.
Weighted occupation time processes associated with the super-Brownian motions on hyperbolic spaces are investigated. Longtime behavior and a central limit type theorem for the processes are obtained. For all dimension d≥2, the right normings for two fluctuations are t and t1/2, and the limit results are the Riemannian measure and some centered Gaussian random measure, respectively.  相似文献   

11.
Analysis on sustainable growth range of population   总被引:2,自引:0,他引:2  
Based on the summarization and the analysis of the obtained research results, the models for local stability and for global stability of ecosystems are developed by means of the theory of dissipative structures, with which the questions on sustainable growth range of population are answered.  相似文献   

12.
Electromechanical dynamics analysis and simulation on a rollforming equipment with both sides variable cross-section are discussed in this study.The system includes mechanical parts and electro-magnetism parts, and it is a strongly coupled electromechanical system.Based on a virtual work principle and given power,generalized forces of this system are obtained.By using Lagrange-Maxwell equations, a model of electromechanical dynamics is established.Differential equations of two-phase winding on d-q axis are obtained by Park transformation, which comes from three-phase winding equations on the A-B-C axis.This system is solved with the 4th order Runge-Kutta’ s method, and discrete solutions of all variables are obtained.Finally, by using Matlab language, the system is simulated.The results show that the proposed method works very well.  相似文献   

13.
<正>1 Introduction Endeavours on learning methods have long occupied the mind spaces of scholars and there have been theories abound on how people learn and in what way organisations can use some of the knowledge gained in the art of learning to maximise human productivity.While the theories by themselves are not solutions to problems,they are steps of inquiry that provide us with interesting perspectives that we can use to extend our knowledge of the dimensions of learning.This paper is an exploratory work on the theories postulated by three notable scholars including Zimmerman  相似文献   

14.
Microscopic halftone image recognition and analysis can provide quantitative evidence for printing quality control and fault diagnosis of printing devices, while halftone image segmentation is one of the significant steps during the procedure. Automatic segmentation on microscopic dots by the aid of the Fuzzy C-Means (FCM) method that takes account of the fuzziness of halftone image and utilizes its color information adequately is realized. Then some examples show the technique effective and simple with better performance of noise immunity than some usual methods. In addition, the segmentation results obtained by the FCM in different color spaces are compared, which indicates that the method using the FCM in the f1f2f3 color space is superior to the rest.  相似文献   

15.
Based on the entransy dissipation extremum principle for thermal insulation process, the constructal optimizations for a plane insulation layer of the steel rolling reheating furnace wall with convective and radiative boundary conditions are carried out by taking the minimization of entransy dissipation rate as optimization objective. The optimal construct of the plane insulation layer is obtained. The results show that for the convective heat transfer boundary condition, the optimal constructs of the insulation layer obtained based on the minimizations of the entransy dissipation rate and heat loss rate are obvi- ously different. Comparing the optimal construct obtained based on the minimization of the entransy dissipation rate with that based on the minimization of the heat loss rate, the entransy dissipation rate is reduced by 5.98 %, which makes the global thermal insulation performance of the insulation layer improve. For the combined convective and radiative heat transfer boundary condition, compared the insulation layer having an increasing thickness with that having constant thickness and a decreasing thickness, the entransy dissipation rates are reduced by 16.59 % and 39.72 %, respectively, and the global thermal insulation performance of the insulation layer is greatly improved.There exits an optimal constant coefficient α2,opt which leads to the minimum dimensionless entransy dissipation rate of the insulation layer. The difference between the optimal constant coefficients α2,opt obtained based on the minimizations of the entransy dissipation rate and the maximum temperature gradient of the insulation layer is small. This makes the corresponding thermal stress obtained based on the minimum dimensionless entransy dissipation rate also be small, and the global thermal insulation performance and thermal safety of the insulation layer are improved simultaneously. The results obtained can provide some guidelines for the optimal designs of the insulation layers.  相似文献   

16.
The characteristics of body build of middle - and old -aged women and its rule of variations as well as the basic sizes of various parts are discussed. All these are based on the body measurements of this age group, and also on the statistical studies of the measurement data. By setting the regression equation, the calculating formulae of various control parts are obtained, thus establishing the prototype of this age group for women.  相似文献   

17.
Difference schemes on non-uniform mesh and their application   总被引:1,自引:0,他引:1  
High order accurate schemes are needed to simulate the multi-scale complex flow fields to get fine structures in simulation of the complex flows with large gradient of fluid parameters near the wall, and schemes on non-uniform mesh are desirable for many CFD (computational fluid dynamics) workers. The construction methods of difference approximations and several difference approximations on non-uniform mesh are presented. The accuracy of the methods and the influence of stretch ratio of the neighbor mesh increment on accuracy are discussed. Some comments on these methods are given, and comparison of the accuracy of the results obtained by schemes based on both non-uniform mesh and coordinate transformation is made, and some numerical examples with non-uniform mesh are presented.  相似文献   

18.
The atomic decompositions of weak Hardy spaces of Banach-space-valued martingales are given. With the help of the atomic decompositions, some inequalities for B-valued martingales are established in the case 0〈r≤1. Here the results are connected closely with the p-uniform smoothness and q-uniform convexity of Banach spaces which the martingales take values in.  相似文献   

19.
The study of fractal analysis over the local fields as underline spaces is very important since it can motivate new approaches and new ideas, and discover new techniques in the study of fractals. To study fractal sets in a local field K, in this paper, we define several kinds of fractal measures and dimensions of subsets in K. Some typical fractal sets in K are constructed. We also give out the Hausdorff dimensions and measures, Box-counting dimensions and Packing dimensions, and stress that there exist differences between fractal analysis on local fields and Euclidean spaces. Consequently, the theoretical foundation of fractal analysis on local fields is established.  相似文献   

20.
This article reports a screw-driven polyhedron linear ultrasonic motor (USM) of nut-type. It is comprised of a stator, which is a threaded metal nut bonded with piezoelectric plates on its external surface, and a rotor with external threads, which engage with the internal threads of the stator. A traveling wave in the plane is stimulated on the stator when harmonic electric signals are applied to the piezoelectric plates. The traveling wave drives the rotor to rotate, and the threads transform the rotation into a linear motion. The lens can be fixed in the rotor and realize the integrated design of the auto focus system. This structure can omit retarder and directly drive to obtain a high accuracy of positioning, and it is shockproof. A mini AF cellular phone module (8.5 mm×8.5 mm×5.9 mm) driven by this motor was made and an image resolution of 3-5 MP was obtained in the module prototypes of the cellular phone.  相似文献   

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