Generalized eigenvectors and fractionalization of offset DFTs and DCTs

The offset discrete Fourier transform (DFT) is a discrete transform with kernel exp[-j2/spl pi/(m-a)(n-b)/N]. It is more generalized and flexible than the original DFT and has very close relations with the discrete cosine transform (DCT) of type 4 (DCT-IV), DCT-VIII, discrete sine transform (DST)-IV, DST-VIII, and discrete Hartley transform (DHT)-IV. In this paper, we derive the eigenvectors/eigenvalues of the offset DFT, especially for the case where a+b is an integer. By convolution theorem, we can derive the close form eigenvector sets of the offset DFT when a+b is an integer. We also show the general form of the eigenvectors in this case. Then, we use the eigenvectors/eigenvalues of the offset DFT to derive the eigenvectors/eigenvalues of the DCT-IV, DCT-VIII, DST-IV, DST-VIII, and DHT-IV. After the eigenvectors/eigenvalues are derived, we can use the eigenvectors-decomposition method to derive the fractional operations of the offset DFT, DCT-IV, DCT-VIII, DST-IV, DST-VIII, and DHT-IV. These fractional operations are more flexible than the original ones and can be used for filter design, data compression, encryption, and watermarking, etc.     

主动式红外光电靶的研究

提出了采用红外光源的主动式光电靶的设计构想，用以消除传统天幕靶在对低速弹测量时，声音对测量的干扰，并设计了整个实验方案，在对静态实验结果进行分析的基础上，证明了该种方法的可行性。     

职业道德建设的调查与思考

近年来各行各业加强职业道德建设,取得了一定成绩,涌现了一大批敬业爱岗、服务社会的岗位明星,但也存在着这样或那样的认识误区或现实局限,如形式主义、短期行为和领导观念异位等,这极大地阻碍了职业道德建设的深入推进。职业道德建设就其特征而言,它具有长期性、时代性和阶级性、相对稳定性以及创新性等属性,对此需要有一个理智而清晰的认识。应从营造良好的社会氛围、制定切实可行的道德准则、进行规范化的教育引导和发挥先进人物的示范作用等几方面入手,把职业道德建设推向深入。     

直齿圆柱变位齿轮的一种测绘方法

在工程实践中对损坏的无图纸齿轮进行重新制造时，测绘是必不可少的环节。在齿面已被严重磨损的情况下，如何准确地得到齿轮尤其是变位齿轮的各项参数是本文所着重讨论的问题。     

A new efficient numerical method and the dynamic analysis of composite laminates with piezoelectric layers

Firstly, a numerical method for the inversion of Laplace transform is developed and its accuracy is shown through examples. Then, a state-vector equation for the dynamic problems of piezoelectric plates is deduced directly from a modified mixed variational principle for piezoelectric bodies and its exact solution for the dynamic problems of simply supported rectangle piezoelectric plate is simply given. For multilayered hybrid plates, we derive the solution in terms of the propagator matrices. The techniques accounts for the compatibility of generalized displacements and generalized stresses on the interface both the elastic layers and piezoelectric layers, and the transverse shear deformation and the rotary inertia of laminate are also considered in the global algebraic equation of structure. Meanwhile, there is no restriction on the thickness and the number of layers. As an application of the numerical inversion of Laplace transform presented in this paper, typical numerical examples of the harmonic vibration and transient response are proposed and discussed. Since the highly accurate numerical results, they can serve as benchmarks to test various thick plate theories and various numerical methods, such as the finite and boundary element methods for transient response problems.     

热焊弯管用钢板工艺探讨

在统计分析、正交多项式回归和模拟试验的基础上，建立了高精度的屈强比预报模型，并运用多元函数极值原理，求导极值点及相应的工艺参数，为优化工艺制度，提高热焊弯管用钢(L360-WG系列)性能合格率提供了定量依据。     

项目经理负责制在设计单位推广初探

论文对我国社会主义市场经济形势下设计单位管理现状进行了分析,对在设计单位推广项目经理负责制的设计组织形式、项目经理的职责及如何发挥项目经理的作用等方面进行了初步探讨。     

Detection and quantification of endolymphatic hydrops in the guinea pig cochlea by magnetic resonance microscopy

The experiments carried out on the model of immobilization stress permit establishing the antiulcer effect of preventive introduction of sodium succinate solution, milk serum solution and solution of milk serum with sodium succinate. A decrease in the degree and number of ulcers and in the integrative indices characterizing the ulcer process after introduction of the studied drugs was accompanied by a fall of the intensity of lipid peroxidation processes.