关键词： Algebraic reconstruction   digital ray tracing   tomography   ultrasound  

摘要： In this paper we have discussed what appears to be a superior implementation of the Algebraic Reconstruction Technique (ART). The method is based on 1) simultaneous application of the error correction terms as computed by ART for all rays in a given projection; 2) longitudinal weighting of the correction terms back-distributed along the rays; and 3) using bilinear elements for discrete approximation to the ray integrals of a continuous image. Since this implementation generates a good reconstruction in only one iteration, it also appears to have a computational advantage over the more traditional implementation of ART. Potential applications of this implementation include image reconstruction in conjunction with ray tracing for ultrasound and microwave tomography in which the curved nature of the rays leads to a non-uniform ray density across the image.

关键词： Riccati equations   Software algorithms   Software packages   Application software   Control systems   Filtering   Symmetric matrices   Transmission line matrix methods   Nonlinear equations   Difference equations  

摘要： Numerical issues related to the computational solution of the algebraic matrix Riccati equation are discussed. The approach presented uses the generalized eigenproblem formulation for the solution of general forms of algebraic Riccati equations arising in both continuous- and discrete-time applications. These general forms result from control and filtering problems for systems in generalized (or implicit or descriptor) state space form. A Newtontype iterative refinement procedure for the generalized Riccati solution is given. The issue of numerical condition of the Riccati problem is addressed. Balancing to improve numerical condition is discussed. An overview of a software package, RICPACK, coded in portable, reliable Fortran is given. Results of numerical experiments are reported.

关键词： 质量   收入   财政管理   有效性系数   企业   企业管理   成本费用   质量成本核算   流动资产平均余额   销售成本   经济性  

摘要： 本文是湖北省黄冈地区经委24岁的青年干部程抱全同志即将于今年6月在英国布赖顿市召开的世界质量会议上宣读的论文。经作者同意在本刊发表,略有删节。

关键词： 数学模型   试验模型   数控切割   数值软件   DDF   计算机算法   凸性   RD   铂丝  

摘要： 本文建立了利用数控切割技术加工精密高度凸轮的数学模型和计算机算法,并编制了数值软件。根据本文所介绍的算法,可精确的计算出数控切割机床钼丝的运动轨迹,消除了原理误差,提高了加工精度和生产效率。现已在生产中应用。

关键词： 标准加入   计算法   内插法   插值法   数值分析   数学计算   光谱测定  

摘要： 本文提出光谱分析中的一种两标准加入数学计算法,其核心是一组(三个)公式,即计算公式、误差公式和校正公式。利用文献数据及实验数据加以验证,证明所提公式准确、可靠,可广泛使用于低含量及微量元素光谱定量分析的计算。两标准加入光谱计算法,目前有两种方法。童式国提出的增量计算法公式简单、可靠,但因公式中引入了感光板的反衬度,这势必增加光谱测定的工作量,并会引入新的误差;标准加入内插法,虽然消去了乳剂的反衬度,但需借助于作图来求解,结果处理麻烦。文献介绍了两种光谱数学计算法,但需要三个标准加入样,不属于两标准加入光

关键词： 产状   地质构造   线状构造   线理   断层面   面状构造   共轭断层   倾侧角   擦痕线   断层两盘   数学计算  

摘要： 地质构造形态的分析,本质上是地质线（线状构造）、地质面（面状构造）在空间几何关系的研究。产生各种构造形态的主应力轴方位,也可依据有关的线状、面状构造的空间几何关系确定出来。因此,运用数学原理进行地质构造分析是完全必要和可能的。

关键词： MACHINE SHOPS  

摘要： The authors seek to place the machines on the shop floor in such a way that, given the technological constraints on equipment installation, they minimize the total transportation costs (of subassemblies, components, and metal waste) subject to the condition that the total piping and wiring cost does not exceed a prespecified value, or alternatively minimize the total piping and wiring cost subject to the condition that the transportation costs do not exceed a prespecified limit. Alternative formulations of the problem focus on minimizing the total costs, including transportation, piping, and wiring, subject to the condition that individual cost components do not exceed prespecified values.

关键词： Linear algebra   Parallel algorithms   Optical signal processing   Signal processing algorithms   Matrix decomposition   Systolic arrays   Equations   Pipeline processing   Image motion analysis   Optical noise  

摘要： Architectures, algorithms, and applications for systolic processors are described with attention to the realization of parallel algorithms on various optical systolic array processors. Systolic processors for matrices with special structure and matrices of general structure, and the realization of matrix-vector, matrix-matrix, and triple-matrix products and such architectures are described. Parallel algorithms for direct and indirect solutions to systems of linear algebraic equations and their implementation on optical systolic processors are detailed with attention to the pipelining and flow of data and operations. Parallel algorithms and their optical realization for LU and QR matrix decomposition are specifically detailed. These represent the fundamental operations necessary in the implementation of least squares, eigenvalue, and SVD solutions. Specific applications (e.g., the solution of partial differential equations, adaptive noise cancellation, and optimal control) are described to typify the use of matrix processors in modern advanced signal processing.

关键词： 版权保护   法律保护   软件   专利保护   版权声明   专利许可证   计算机程序   数学算法   固件   商标保护   目标代码程序   转销   商业秘密   副本   CCPA  

摘要： 当我们引进国外的计算机系统或带有计算机的其他各类系统时,我们常想知道:可以公开地复制、移植或转销这些系统中的软件或固件吗?甚至我们还想了解:在合同中所提到的软件或固件许可证、转销权、复制权等究竟有多大的法律效力或实际意义呢? 当我们探索国际合作,把我们的软件或固件产品打入国际市场时,更应了解:如何来保护我们的成果和利益,如何才能不因为我们不深通软件和固件的保护法而贱卖了我们的成果,致使“肥水流入他人田”呢? 当我们在制订我国的软件或固件专利法时,或当在国内进行软件或固件的合作开发时我们很想借鉴一下国外的一些法律、规定、弊病和发展过程。 当读者确有以上这些需要时,我们推荐阅读本专论。本文虽然稍嫌冗长,但并非言之无物。