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961.
基于MFC技术的手机模拟器在PC上的实现 总被引:2,自引:0,他引:2
手机模拟器是在PC上运行、测试和调试手机软件的仿真工具,模拟器提供了前端类似真实手机的图形用户界面(GUI),开发者可以使用模拟器完成手机软件的前期开发和测试.国内此种产品还非常少,因此利用微软的MFC类库开发了手机模拟器,结果证明与不用模拟器相比,大大的提高了手机软件的开发速度.与其它国外的手机模拟器和手机软件源代码采用两个独立进程不同,采用了两部分代码共享一个进程空间的办法,有利于跟踪程序错误,避免了两个进程间同步的难题.该模拟器还采用Windows的内存池模拟了手机的RAM,用Windows操作系统模拟了手机操作系统,这也是其它国内模拟器所没有的技术. 相似文献
962.
以新舟60飞机为模型,C 语言为开发工具,开发出一套完整可行的飞行指引(F/D)软件.用以替代Collins APS-85飞控计算机完成飞行指引功能,并成功地在飞行模拟机上通过测试且得到应用.具有成本低廉,稳定可靠的特点,能够满足飞行员训练的需要. 相似文献
963.
964.
The electromagnetic parameters of microwave absorbing materials are important criteria when appraising the properties of absorbents. For reconstruction of parameters which belongs to the inverse scattering problem, the test data in requirement of traditional impedance method are "just enough" and not "redundant" to comprehensively evaluate the electromagnetic properties of materials. A novel optimization approach involving multiple impedance measurements is introduced in this paper to implement automatic measurement for electromagnetic parameters on microwave slot-line. Some results for standard samples and microwave absorbing materials are given. 相似文献
965.
An iteration algorithm for the analysis of speckle interference patterns is presented. First, four digitized phase-shifted patterns are locally averaged. The phase information is then extracted by the usual phase shift algorithm. The wrapped phase is in turn used to reconstruct four new phase-shifted patterns. These three steps form a cycle. Repetition of the three steps has a great effect on suppressing speckle noise. Theoretical study shows that the iterated phase converges to a perfect result under ideal conditions. In general, the iteration causes little error but improves the phase information a great deal. The signal-to-noise ratio rises when additional iterations are performed. 相似文献
966.
Constraint Satisfaction Problem (CSP) is an important problem in artificial intelligence and operations research. Many practical problems can be formulated as CSP, i.e., finding a consistent value assignment to variables subject to a set of constraints. In this paper, we give a quantitative approach to solve the CSPs which deals uniformly with binary constraints as well as high order,k-ary (k ≥ 2) constraints. In this quantitative approach, using variable transformation and constraint transformation, a CSP is transformed into a satisfiability (SAT) problem. The SAT problem is then solved within a continuous search space. We will evaluate the performance of this method based on randomly generated SAT problem instances and regularly generatedk-ary (k ≥ 2) CSP problem instances. 相似文献
967.
A scheme for the design of diffractive phase elements (DPE's) that integrates several optical functions is presented in a consistent sense based on the general theory of amplitude-phase retrieval and the Yang-Gu algorithm [Appl. Opt. 33, 209 (1994)]. We extend the original Yang-Gu algorithm to treat a system illuminated by a beam of incident light whose components are at different wavelengths, and a set of equations for determining the phase distribution of the DPE is derived. The profile of a surface-relief DPE can be designed with an iterative algorithm. Numerical simulations are carried out for the design of one-dimensional DPE's capable of both demultiplexing different wavelength components and focusing each partial wave at predetermined positions. The influence of the extension of sampling points in the DPE's from ideal geometric points to physical spots on design results is also investigated. The numerical simulation results show that the new algorithm can be used successfully to design the desired DPE's. It is therefore expected to be useful in the design of DPE's for micro-optical systems. 相似文献
968.
催化裂化装置龟甲网双层衬里的改进 总被引:1,自引:1,他引:0
顾一天 《石油化工设备技术》1995,16(2):25-28
通过对催化裂化装置老的龟甲网双层社里使用情况的调查研究以及对存在问题的分析,提出了改进措施。经近几年的实际应用考核证明,改进措施是行之有效的。在此基础上制订了院标“BL型隔热耐磨衬里施工技术要求”。 相似文献
969.
Directed melt oxidation (DMOX) of pure aluminium has been used to produce Al/Al2O3 composites by growth into a particulate alumina filler in the absence of any dopants apart from a -Al2O3 impurity in the filler. The microstructural development and mechanisms of growth of these composites have been investigated. It is shown that the Al2O3 filler used in this work has both chemical and physical effects on the reaction process. The -Al2O3 impurity introduces sodium into the system; this increases the wettability of alumina (both filler and oxidation reaction product) by molten aluminium, and initiates DMOX reactions. In addition, the filler particle size has an effect on the directed oxidation reaction. If the particle size is too fine, no oxidation growth takes place. Filler particles limit the ingress of oxygen through the reaction front so that AIN instead of Al2O3 may be formed in regions behind the main reaction front. Although such AIN production is seen when magnesium is used as a dopant to initiate DMOX reactions in the Al/Al2O3 system, it is more marked with sodium, because the latter has a greater effect on the wettability of alumina by aluminium. 相似文献
970.
目的:识别核桃油中同时掺入多种其他植物油的多元掺伪。方法:采用气相色谱技术分析核桃油、菜籽油掺伪混合物中脂肪酸含量,结合化学计量方法对气相色谱数据进行建模,并对不同比例核桃油、菜籽油混合物进行判别分析。结果:主成分分析法(PCA)能快速鉴别出纯核桃油和掺伪核桃油,并在一定程度上反映样本的掺伪比例;Bayes判别分析将83.33%的样品归入正确的分类;偏最小二乘判别分析法(PLS-DA)的判别准确率达87.50%;基于BP神经网络模型的判别分析,其训练集的正确率为84.21%,测试集的正确率为80.00%;基于遗传算法优化支持向量机(SVM-ga)的判别分析,其训练集和测试集的正确率均为100%。结论:多种分析模型均能不同程度地识别核桃油、菜籽油掺伪比例,其中SVM-ga模型的预测精度最佳。 相似文献