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601.
教学执行力是教师从事教学工作的能力,是教师素质的重要展示,科学、公平、公正地评价教师的教学执行力益于引导教师提高素质.采用"三选法"探讨教师教学执行力评价指标内容、用矩阵法确定指标权重、评价量化数值采用三参数区间数表示,并转化为联系数处理数据运算,方法更加方便、有效.  相似文献   
602.
在联系数理论的基础上,针对评标中某些权重不宜用定值表示的问题,采用三参数区间数表示,并转化为联系数以表示权重,结合综合评价方法建立多指标评价模型来解决多属性决策问题,在招标决策中体现出方法的简易、有效.  相似文献   
603.
Tulsi Dass 《Pramana》1984,23(4):433-443
A general framework for the gauge theory of the affine group and its various subgroups in terms of connections on the bundle of affine frames and its subbundles is given, with emphasis on the correct gauging of groups including space-time translations. For consistency of interpretation, the appropriate objects to be identified with gravitational vierbeins in such theories are not the translational gauge fields themselves, but their pull backs,via appropriate bundle homomorphisms, to the bundle of frames. This automatically solves the problems usually encountered in constructing a gauge theory of the conventional sort for groups containing translations. We give a consistent formulation of the Poincare gauge theory and also of the theory based on translational gauge invariance which, in the absence of matter fields with intrinsic spin, gives a local Lorentz invariant theory equivalent to Einstein gravity.  相似文献   
604.
The left semi-tensor product of matrices was proposed in [2]. In this paper the right semi-tensor product is introduced first. Some basic properties are presented and compared with those of the left semi-tensor product.Then two new applications are investigated. Firstly, its applications to connection, an important concept in differential geometry, is considered. The structure matrix and the Christoffel matrix are introduced. The transfer formulas under coordinate transformation are expressed in matrix form. Certain new results are obtained.Secondly, the structure of finite dimensional Lie algebra, etc. are investigated under the matrix expression. These applications demonstrate the usefulness of the new matrix products.  相似文献   
605.
聂智 《数学杂志》2004,24(5):537-542
利用Chern联络D、Cartan张量A以及第二基本形式H.研究了Finsler子流形中的诱导Chern联络与第一、第二曲率R和P,给出了子流形的关于R曲率、P曲率以及flag曲率的Gauss方程。  相似文献   
606.
基于模糊判决的图像边缘连接   总被引:8,自引:1,他引:7  
杨绍清  贾传荧 《光学技术》2002,28(2):108-109
边缘连接是图像边缘提取中的一项重要的后处理技术。基于模糊判决理论 ,在由Sobel算法得到的边缘图像的基础上 ,给出了一套行之有效的边缘连接技术。结果表明 ,用所提出的算法提取目标图像的边缘时 ,能够在保持原有图像不失真的情况下 ,较大地提高边缘图像边界的连通性 ,为光电跟踪器和成像雷达的目标检测、跟踪和识别等提供了良好的基础。因而 ,本算法具有较高的实际应用价值  相似文献   
607.
The projective transformation of the special semi-symmetric metric recurrent connection is studied in this paper. First of all, an invariant under this transformation is granted; Secondly, by inducing of the invariant and making use of the properties that the corresponding covariant derivative keeps being fixed under the distinctness connection, the curvature tensor expression of the Riemannian manifold is posed at the same time.  相似文献   
608.
Natural convection mass transfer rates at both vertical and horizontal serially connected tubes were reported using the electrochemical technique involving the measurement of limiting currents for the deposition of copper on copper cylinders from acidified cupric sulphate solutions. Measurements were carried out with: (a) one tube active; (b) two tube surfaces active; (c) three tube surfaces active.

The electrolyte concentration and a number of serial connections of tubes were varied to provide a range of GrSc extending from 5.3×108 to 9.5×1011. The mass transfer rates at serially connected horizontal cylinders were in good agreement with mass transfer data in the literature. Correlation of results covered both laminar and turbulent conditions separately. The mass transfer rates at serially connected vertical cylinders were controlled by the boundary layer development at the multi-electrodes. The results for vertical electrodes, which are single, serially connected two and three electrodes, were separately correlated in the turbulent region.

The results illustrate the important effect of boundary layer development in determining current distribution in multi-electrode electrochemical cells.  相似文献   

609.
本文给出伏安法测量电阻时,安培计内、外接法的定量选择公式,定量地描绘了使测量误差在允许范围所需要采取的具体措施。  相似文献   
610.
We give a simple formula for the operator C 3 of the standard deformation quantization with separation of variables on a Kähler manifold M. Unlike C 1 and C 2, this operator cannot be expressed in terms of the Kähler–Poisson tensor on M. We modify C 3 to obtain a covariant deformation quantization with separation of variables up to the third order which is expressed in terms of the Poisson tensor on M and can thus be defined on an arbitrary complex manifold endowed with a Poisson bivector field of type (1,1).  相似文献   
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