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1.
Let F be a locally defined formation consisting of locally soluble groups,G a hyper-(cyclic or finite)locally soluble group and A a noetherian ZG-module with all irreducible ZG-factors being finite,G∈F,f(∞)≌f(p),f(P)≠Фfor each P∈π.The following conclutions are obtained:(1)if there exists a maximal submodule B of A such that A/B is F central in G and B has no nonzero F centml ZG-factors,then A has an F decomposition;(2)if there exists an irreducible F central submodule B of A such that all ZG-composition factors of A/B are F ecentric,then A has an F decomposition.  相似文献   

2.
Let Fbe a formation locally defined by f(p), G∈ Fand A a ZG-module, where p∈π={all primes and symbol ∞}.Then a p-main-factor U/V of G is said to be F -central in G if G/CG(U/V)∈f(p). In this paper, we have proved that: let Fbe a locally defined formation consisting of locally soluble groups, G a hyper-(cyclic or finite) locally soluble group and A an artinian ZG-module with all irreducible ZG-factors of A being finite; if G ∈ F, f(∞) f(p), f(p)≠ for each p∈π, A has an F -decomposition.  相似文献   

3.
On the basis of the quasi-isomorphism of finite groups, a new mapping, weak isomorphism, from a finite group to another finite group is defined. Let G and H be two finite groups and G be weak-isomorphic to H. Then G≌H if G satisfies one of the following conditions. 1) G is a finite Abelian group. 2) The order of G is p^3. 3 ) The order of G is p^n+1 and G has a cyclic normal subgroup N = 〈a〉 of order p^n. 4) G is a nilpotent group and if p^││G│, then for any P ∈ Sylp (G), P has a cyclic maximal subgroup, where p is a prime; 5) G is a maximal class group of order p4(p〉3).  相似文献   

4.
The notion of the inner product of vectors is extended to tensors of different orders, which may replace the vector product usually. The essences of the differential and the codiffcrential forms are pointed out: they represent the tangent surface and the normal surface fluxes of a tensor, reslpetivcly. The definitions of the divergence and the curl of a 2D surface flux of a tensor arc obtained. Maxwell's equations, namely, the constraction law of field, which were usually established based on two conservation laws of electric charge and imaginary magnetic charge, are derived by the author only by using one conservation law ( mass or fluid flux quantity and so on) and the feature of central field (or its composition). By the feature of central field (or its composition), the curl of 2D flux is zero. Both universality of gauge field and the difficulty of magnetic monopole theory ( a magnetic monopole has no effect on electric current just like a couple hasing no effect on the sum of forces) axe presented: magnetic monopole has no the feature of magnet. Finally it is pointed out that the base of relation of mass and energy is already involved in Maxwell's equations.  相似文献   

5.
设G(V,E)是2一边连通无向简单图,D(V,A)是G的一个定向图,A(D)为D的弧集,若映射f:A(D)→{…,-n,-(n-1),…,-1,0,1,…,n,…}满足Au∈V(D)有f^ (u)=f^-(u),则称<D,f>为一流图。其中f^ (u)=∑vu∈A(D)f(vu),f^-(u)=∑uv∈A(D)F(UV)。对Aa∈A(D),当f(a)≠0时,称<D,f>为非零流图,对非零流图。对非零流图<D,f>,称所有|f(a)|和最小值的流f为D的最小流。本文研究了这类流的若干问题。  相似文献   

6.
The extended finite element method(XFEM) is a numerical method for modeling discontinuities within a classical finite element framework. Based on the algorithm of XFEM, the major factors such as integral domain factor and mesh density which all influence the calculation accuracy of stress intensity factor(SIF) are discussed,and the proper parameters to calculate the SIF are given. The results from the case analysis demonstrate that the crack path is the most sensitive to the crack growth increment size, and the crack path is not mesh-sensitive. A reanalysis method for the XFEM has been introduced. The example presented shows that there is a significantly reduced computational cost for each iteration of crack growth achieved by using the reanalysis method and the reanalysis approach has increasing benefits as the mesh density increases or the value of crack growth increments size decreases.  相似文献   

7.
A subgroup H of G is called s-conditionally permutable in G if for every Sylow subgroup T of G,there exists an element x∈G such that HTx=TxH.In this paper,we investigate further the influence of s-conditionally permutability of some 2-maximal subgroups of the Sylow subgroup of G,on the structure of finite groups.New criteria for a group G being p-nilpotent are obtained.  相似文献   

8.
A random allocation scheme for SDMA systems is proposed with a goal of more efficient dynamic allocation. Based on theoretical analysis and derivation, the blocking probability of the proposed scheme is calculated and compared with those of the ftrst duplicate (FD) and duplicate last (DL) schemes with different state-independent probabilities (p,) of acquring a dupicate channel suecessfully and 5 resources; moreover, a more realistic performance analysis of the random scheme is made with state-dependent ps in the SDMA/CDMA environment. The results show that the random scheme has a similar allocation pefformace to the FD and DL schemes, but is simpler than them in computation and scheduling.  相似文献   

9.
Journal of Southwest Jiaotong University ( English Edition), J SWJTU (EE) , is a comprehensive academic journal facing the world; it mainly publishes up-to-date original papers on science and technology. By the end of 2005, J SWJTU(EE) has already issued 13 volumes, totally 25 issues. To meet the demand of readers and writers for more frequent issues, the Journal will change into a quarterly from 2005, published on the 30th of Jan. , Apr. , July and Oct, respectively.  相似文献   

10.
Objective To investigate the role of peripheral lymphocytes Sialyl Lewis(x) (CD15s) antigen before and after kidney transplantation. Methods Flow cytometry technique was applied to examine the expression of peripheral lymphoid cell surface CD15s antigen after renal transplantation, and to evaluate various therapeutic regimen. Results The statistic analysis results of peripheral lymphoid cell surface CD15s antigen expression level showed that there was significant difference among the patients with acute rejection, long-term dialysis and with normal renal function post-transplant; significant difference of CD15s expression level between group of rejection and infection; no significant difference of CD15s expression among the different groups treated by various therapeutic regimens. Conclusion The different therapeutic regimen has no influence to CD15s expression; Detection of peripheral lymphoid cell surface CD15s antigen expression periodically, intelligently make convenience to understand suitable status of immunosuppression.  相似文献   

11.
IntroductionLet D be a domain in C.Define for f mero-morphic on D and a,b∈C,we putE(a,f)={z∶f(z)-a=0}where a zero of multiplicity m is counted m times inthe set.And put-E(a,f)=f-1({a})∩D={z∈D∶f(z)=a}Then f and g share a IM(ignoring multiplicities),i.e.-E(a,f)=-E(a,g)If f-a and g-a have the same zeros with thesame multiplicities,then f and g share the value aCM(counting multiplicities),i.e.E(a,f)=E(a,g)A meromorphic function f on C is called anormal function if there exists a posit…  相似文献   

12.
Laser shock processing (LSP) has been proposed as a new surface treatment for improving hardness, wear resistance and fatigue. In this paper, the effect of LSP on brass is investigated with experiment. Micro-hardness, roughness, microstructure, wear resistance and friction coefficient evolution are investigated for different parameters of LSP. The result shows that the roughness increases after LSP; no ablation is observed; the microstructure has no remarkable ehange; hardness and the wear resistance increase as the pulse density increases.  相似文献   

13.
Given a graph G and a non-negative integer h, the h-restricted connectivity k^h(G) of G is the minimum cardinality of a set of vertices of G, in which at least h neighbors of any vertex is not included, if any, whose deletion disconnects G and every remaining component has the minimum degree of vertex at least h; and the h-extra connectivity k^h(G) Of G is the minimum cardinality of a set of vertices of G, if any, whose deletion disconnects G and every remaining component has order more than h. This paper shows that for the hypercube Qn and the folded hypercube FQn, k1(Qn)=k^(1)(Qn)=2n-2 for n≥3, k2(Qn)=3n-5 for n≥4, k1(FQn)=k^(1)(FQn)=2n for n≥4 and k^(2)(FQn)=4n-4 for n≥8.  相似文献   

14.
Suppose V is a vector space over the real orcomplex field F.A linear transformation T on Vis a function T from V into itself such that T(αx βy) =αTx βTy holds for any vectors x,y∈ V,and any scalarsα,β∈ F.Linear transformationsare applied to represent linear systems.A systemis said to interpolate[1] a family Soflinear transfor-mations if for each input of the system the corre-sponding output can be obtained by the action ofsome member of S.Thatis,if foreach x∈V,Tx= Qxx,for some …  相似文献   

15.
ON THE EXISTENCE OF THE h-RESTRICTED EDGE CONNECTIVITY OF A GRAPH   总被引:1,自引:0,他引:1  
IntroductionLet G=(V,E) be a finite,simple and undi-rected graph with vertex set V and edge set E.We' ll follow the terminology and notation of Ref.[1 ]and terms not defined here can be found inRefs.[1 ,2 ].A set S of edges of G is called an edgedisconnecting set if G - S is disconnected. Theusual edge connectivityλ(G) of G is the minimumcardinality over the all edge disconnecting sets ofG.Note that,in the above definition,absolutelyno conditions or restrictions are imposed either onthe…  相似文献   

16.
图Pm∨Wn与Wm∨Wn的第一类弱全色数   总被引:1,自引:1,他引:0  
对简单图G(V,E),f是从V(G)∪E(G)到{1,2,…,k}的映射,k是自然数,若f满足(1)uv∈E(G),u≠v,f(u)≠f(v);(2) uv,uw∈E(G),v≠w,f(uv)≠f(uw);则称f是G的第一类弱全染色.给出了路与轮,轮与轮联图的第一类弱全色数.  相似文献   

17.
With the aim of sending electric power to autonomous underwater vehicles (AUVs), an automatic wireless power supply system by means of electromagnetic coupler was proposed. An equivalent circuit of the electromagnetic coupler with compensating capacitors was presented to analyze the performance of the system. The magnetizing inductance and leakage inductance, which are important for choosing compensating capacitors, were calculated by finite element analysis (FEA) methods. Then the voltage gain, power loss and system efficiency were analyzed to optimize the winding turns. Finally, a phase-shift full bridge zero-voltage-switching converter and an electromagnetic coupler were produced. The experimental results demonstrated that the proposed system has a high voltage gain with small variation and sufficient power feeding.  相似文献   

18.
Let X = (x1 ,x2 ,…… ,xn ) and F(X) be a fuzzy set on a universal set X. A new def'mition of fuzzy entropy about a fuzzy set A on F(X), e^*' , is defined based on the order relation "≤" on [ 0,1/2 ]^n. It is proved that e^* is a σ-entropy under an additional requirement. Besides, some entropy formulas are presented and related properties are discussed.  相似文献   

19.
Projection welding is a variation of electric resistance welding with the dynamic changes of the flow paths for heat and electrical properties with changing temperature caused by the large plastic deformation collapse of projection. As the joint type between the auto door hinge and the inner plate, projection welding may bring welding distortions and would affect the assembly quality of auto body. A comprehensive electric-thermal-mechanical numerical simulation was performed to quantitatively simulate the processes of projection welding by using a coupled finite element method. The mechanism of projection collapse and the formation process of nugget were discussed and good conclusions have been achieved comparing with the test results.  相似文献   

20.
对于一个(p,g)图G,如果存在一个v(G)到非负整数集N0的一个映射以称为顶点标号)满足:(1)f(u)≠f(v),其中u≠v,且u,v∈V,(c);(2){f(u)+f(v)|uv∈E(G))={k,k+d,…,k+(g-1)d),称图G为(k,d)-算术图。证明了图Fm.4是(d,2d)-算术图和图Fm.6是(d,3d)-算术图。  相似文献   

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