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941.
在C/S结构应用系统中,有效安全地运行客户端的应用程序是实现C/S结构应用系统的基础,通过分析Windows系统的特点,引入系统级服务进程实现对客户端应用的监控确保了客户端程序被强行结束或绕开运行,再利用已经运行的客户端应用程序反过来实现对系统级服务进程进行监控,从而确保了客户端应用程序的有效运行和工作.  相似文献   
942.
许永达 《计算机系统应用》2013,22(3):153-156,181
C语言指针的有些错误在程序编译阶段难以发现,且现行教材主要从概念、理论上对指针错误进行讲述,存在不足.分析了带有此类错误的示例程序,并在VISUAL C++6.0进行调试,展示此类指针错误的错误现象,分析其产生的原因,提出正确使用指针的方法,以达到预防此类指针错误发生的目的.  相似文献   
943.
本设计是以SEP4020为控制芯片,以μC/OS-II为实时操作系统来管理各个任务,移入了μC/GUI来完成TFT彩色液晶屏的操作,加入FAT32文件系统来对SD卡的数据存储功能进行操作,以TLC2543作为数据采集模块的多通道便携式发动机检测装置.实现了数据的实时采集,数据的显示和存储功能.该设计具有结构简单,易于实现,操作方便,效率高,实时性强,移动和通用性好的特点.  相似文献   
944.
以作者所在单位产品制造过程信息控制管理系统为例,详细描述了系统的方案与设计,阐述了基于C/S结构的产品条码管理系统的设计及其实现的关键技术,介绍了该系统的各个功能模块及数据库的实现方法。  相似文献   
945.
Microsoft office系列软件在日常工作中应用广泛。我单位在工程项目中大量使用Office软件进行数据处理及交换,对这些原始数据采取适当的方法分析挖掘,可以极大地缩短设计与试验周期、降低成本。由于项目产生的临时数据常以不同格式存放在各种办公软件中,且数量巨大,所以需要一个可以控制Office系列办公软件的程序来完成原始信息的收集及输出。给出了通过使用基于C++的Qt框架并结合COM、ODBC技术获取、处理数据,并输出至数据库或XML文档的实现方法。  相似文献   
946.
王芸 《计算机时代》2013,(12):73-75
基于积件思想,对五年制高职计算机课程项目式教学进行探索,以C语言程序设计为例研究分析,并组建C语言程序设计课程知识点积件库,编写高职C语言程序设计课程项目式校本教材,分析C语言程序设计课程教学项目“阶梯电价计费”.并借助开源平台Moodle实现了教学项目的应用.  相似文献   
947.
In this paper, the problem of robust H control is investigated for sampled-data systems with probabilistic sampling. The parameter uncertainties are time-varying norm-bounded and appear in both the state and input matrices. For the simplicity of technical development, only two different sampling periods are considered whose occurrence probabilities are given constants and satisfy Bernoulli distribution, which can be further extended to the case with multiple stochastic sampling periods. By applying an input delay approach, the probabilistic sampling system is transformed into a continuous time-delay system with stochastic parameters in the system matrices. By linear matrix inequality (LMI) approach, sufficient conditions are obtained, which guarantee the robust mean-square exponential stability of the system with an H performance. Moreover, an H controller design procedure is then proposed. An illustrative example is included to demonstrate the effectiveness of the proposed techniques.  相似文献   
948.
The interaction interface between two molecules can be represented as a bisector surface equidistant from the two sets of spheres of varying radii representing atoms. We recursively divide a box containing both sphere-sets into uniform pairs of sub-boxes. The distance from each new box to each sphere-set is conservatively approximated by an interval, and the number of sphere-box computations is greatly reduced by pre-partitioning each sphere-set using a kd-tree. The subdivision terminates at a specified resolution, creating a box partition (BP) tree. A piecewise linear approximation of the bisector surface is then obtained by traversing the leaves of the BP tree and connecting points equidistant from the sphere-sets. In 124 experiments with up to 16,728 spheres, a bisector surface with a resolution of 1/24 of the original bounding box was obtained in 28.8 ms on average.  相似文献   
949.
Embedding a number of displacement features into a base surface is common in industrial product design and modeling, where displaced surface regions are blended with the unmodified surface region. The cubic Hermite interpolant is usually adopted for surface blending, in which tangent plane smoothness across the boundary curve is achieved. However, the polynomial degree of the tangent field curve obtained symbolically is considerably higher, and the reduction of the degree of a freeform curve is a non-trivial task. In this work, an approximation surface blending approach is proposed to achieve tangential continuity across the boundary curve. The boundary curve is first offset in the tangent field with the user-specified tolerance, after which it is refined to be compatible with the offset curve for surface blending. Since the boundary curve is offset in a three-dimensional (3D) space, the local self-intersection in the offset curve is addressed in a 2D space by approximately mapping the offset vectors in the respective tangent planes to the parameter space of the base surface. The proposed algorithm is validated using examples, and the normal vector deviation along the boundary curve is investigated.  相似文献   
950.
In this new version of ISICS, called ISICS2011, a few omissions and incorrect entries in the built-in file of electron binding energies have been corrected; operational situations leading to un-physical behavior have been identified and flagged.

New version program summary

Program title: ISICS2011Catalogue identifier: ADDS_v5_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADDS_v5_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 6011No. of bytes in distributed program, including test data, etc.: 130 587Distribution format: tar.gzProgramming language: CComputer: 80486 or higher-level PCsOperating system: WINDOWS XP and all earlier operating systemsClassification: 16.7Catalogue identifier of previous version: ADDS_v4_0Journal reference of previous version: Comput. Phys. Commun. 180 (2009) 1716.Does the new version supersede the previous version?: YesNature of problem: Ionization and X-ray production cross section calculations for ion–atom collisions.Solution method: Numerical integration of form factor using a logarithmic transform and Gaussian quadrature, plus exact integration limits.Reasons for new version: General need for higher precision in output format for projectile energies; some built-in binding energies needed correcting; some anomalous results occur due to faulty read-in data or calculated parameters becoming un-physical; erroneous calculations could result for the L and M shells when restricted K-shell options are inadvertently chosen; to achieve general compatibility with ISICSoo, a companion C++ version that is portable to Linux and MacOS platforms, has been submitted for publication in the CPC Program Library approximately at the same time as this present new standalone version of ISICS [1].Summary of revisions: The format field for projectile energies in the output has been expanded from two to four decimal places in order to distinguish between closely spaced energy values. There were a few entries in the executable binding energy file that needed correcting; K shell of Eu, M shells of Zn, M1 shell of Kr. The corrected values were also entered in the ENERGY.DAT file. In addition, an alternate data file of binding energies is included, called ENERGY_GW.DAT, which is more up-to-date [2]. Likewise, an alternate atomic parameters data file is now included, called FLOURE_JC.DAT, which is more up-to-date [3] fluorescence yields for the K and L shells and Coster–Kronig parameters for the L shell. Both data files can be read in using the -f usage option. To do this, the original energy file should be renamed and saved (e.g., ENERGY_BB.DAT) and the new file (ENERGY_GW.DAT ) should be duplicated as ENERGY.DAT to be read in using the -f option. Similarly for reading in an alternate FLOURE.DAT file. As with previous versions, the user can also simply input different values of any input quantity by invoking the “specify your own parameters” option from the main menu. You can also use this option to simply check the values of the built-in values of the parameters. If it still happens that a zero binding energy for a particular sub-shell is read in, the program will not completely abort, but will calculate results for the other sub-shells while setting the affected sub-shell output to zero. In calculating the Coulomb deflection factor, if the quantity inside the radical sign of the parameter zs becomes zero or negative, to prevent the program from aborting, the PWBA cross sections are still calculated while the ECPSSR cross sections are set to zero. This situation can happen for very low energy collisions, such as were noticed for helium ions on copper at energies of E?11.2 keV. It was observed during the engineering of ISICSoo [1] that erroneous calculations could result for the L- and M-shell cases when restricted K-shell R or HSR scaling options were inappropriately chosen. The program has now been fixed so that these inappropriate options are ignored for the L and M shells. In the previous versions, the usage for inputting a batch data file was incorrectly stated in the Users Manual as -Bxxx; the correct designation is -Fxxx, or alternatively, -Ixxx, as indicated on the usage screen in running the program.A revised Users Manual is also available.Restrictions: The consumed CPU time increases with the atomic shell (K, L, M), but execution is still very fast.Running time: This depends on which shell and the number of different energies to be used in the calculation. The running time is not significantly changed from the previous version.References:
  • [1] 
    M. Batic, M.G. Pia, S. Cipolla, Comput. Phys. Commun. (2011), submitted for publication.
  • [2] 
    http://www.jlab.org/~gwyn/ebindene.html.
  • [3] 
    J. Campbell, At. Data Nucl. Data Tables 85 (2003) 291.
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