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101.
根据对称群的基本性质以及第二同构定理,给出了通过添加生成元到P群来构造对称群的一个Sylow-p子群的定理,添加的生成元保证能够快速得到对称群的一个Sylow—p子群.根据第二西洛定理求出了所有共轭子群,即所有Sylow-p子群.针对求所有共轭子群过程中面临共轭子群出现重复的问题,利用正规化子的性质,找到使得两个Sylow-p子群共轭的元,保证每次求的Sylow-P子群不重复.将此算法应用于S1,实验表明该算法可操作性强,耗费时间少. 相似文献
102.
证明了下面的结论:1.若R是有单位元1的环,则Mn(R)作为环与R-模可由两个元生成;2.设F是域,Mn(F)作为F-代数可由两个元生成,且Mn(F)的任意非中心元皆可作为极小生成集中的一员;3.设F是特征为零的域,则Mn(F)的上三角矩阵子代数可由两个元生成 相似文献
103.
JIANG Long Department of Mathematics China University of Mining Technology Xuzhou China Institute of Mathematics Fudan University Shanghai China School of Mathematics System Sciences Shandong University Jinan China 《中国科学A辑(英文版)》2006,49(10):1353-1362
This paper establishes a limit theorem for solutions of backward stochastic differential equations (BSDEs). By this limit theorem, this paper proves that, under the standard assumption g(t,y,0) = 0, the generator g of a BSDE can be uniquely determined by the corresponding g-expectationεg;this paper also proves that if a filtration consistent expectation S can be represented as a g-expectationεg, then the corresponding generator g must be unique. 相似文献
104.
105.
We develop the method introduced previously, to construct infinitesimal generators on locally compact group C
*-algebras and on tensor product of C
*-algebras. It is shown in particular that there is a C
* -algebra A such that the C
*-tensor product of A and an arbitrary C
*-algebra B can have a non-approximately inner strongly one parameter group of *-automorphisms. 相似文献
106.
107.
Using the harmonic version of the generator coordinate method, and Skyrme interaction, the frequencies of the isoscalar breathing
and quadrupole modes are related to the relevant incompressibility coefficients. The possibility of extending this to spin
modes is also examined. It is found that a spin incompressibility coefficient is negative for a particular set of Skyrme parameter
for4He. Other sets produce low positive values and these in turn could imply a relatively low lyingS=2,T=1 state. The replacement of the three-body term by the density-dependent one, suggested by Chang provides a cure for this
pathology. 相似文献
108.
We discuss in detail the parasupersymmetric quantum mechanics of arbitrary order where the parasupersymmetry is between the
normal bosons and those corresponding to the truncated harmonic oscillator. We show that even though the parasusy algebra
is different from that of the usual parasusy quantum mechanics, still the consequences of the two are identical. We further
show that the parasupersymmetric quantum mechanics of arbitrary orderp can also be rewritten in terms ofp supercharges (i.e. all of which obeyQ
i
2
=0). However, the Hamiltonian cannot be expressed in a simple form in terms of thep supercharges except in a special case. A model of conformal parasupersymmetry is also discussed and it is shown that in this
case, thep supercharges, thep conformal supercharges along with HamiltonianH, conformal generatorK and dilatation generatorD form a closed algebra. 相似文献
109.
Walter Schempp 《Acta Appl Math》1997,48(2):185-234
Due to its unequalled advantages, the magnetic resonance imaging (MRI) modality has truly revolutionized the diagnosis and evaluation of pathology. Because many morphological anatomic details that may not be visualized by other high tech imaging methods can now be readily shown by diagnostic MRI, it has already become the standard modality by which all other clinical imaging techniques are measured. The unique quantum physical basis of the MRI modality combined with the imaging capabilities of current computer technology has made this imaging modality a target of interdisciplinary interest for clinicians, physicists, biologists, engineers, and mathematicians. Due to the fact that MRI scanners perform corticomorphic processing, this modality is by far more complex than all the other high tech clinical imaging techniques. The purpose of this paper is to outline a phase coherent wavelet approach to Fourier transform MRI. It is based on distributional harmonic analysis on the Heisenberg nilpotent Lie group G and the associated symplectically invariant symbol calculus of pseudodifferential operators. The contour and contrast resolution of MRI scans which is controlled by symplectic filter bank processing gives the noninvasive MRI modality superiority over X-ray computed tomography (CT) in soft tissue differentiation. 相似文献
110.
单重态氧发生器出口气流中水汽含量的光谱测量法 总被引:1,自引:1,他引:0
水汽的含量是化学法单重态氧发生器(SOG)的重要性能参数之一,因为它不仅对O_2( ̄1△)有猝灭作用,而且在氧碘化学激光器(COIL)光腔中对I ̄*也有严重猝灭作用。因此测控SOG出口处的水汽含量有重要意义。本实验采用光谱强度比较法测量SOG中的水汽含量,利用OMA-3的二维扫描积累功能,可对不同测点的光谱进行同时扫描积累,从而可以对SOG的数个测点同时进行水汽含量测定。测试精度可达±10%。 相似文献