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91.
92.
崔彩霞 《数字社区&智能家居》2009,(12)
根据当前高等师范院校计算机专业人才培养的特点和离散数学的教学现状,从离散数学的教学内容、教学手段和实验教学等方面探讨了计算机专业离散数学的教学改革。通过这几年的改革实践,离散数学的教学效果得到了明显提高。 相似文献
93.
94.
针对目前手机的高普及、高智能和安全性差的问题,统计并研究了不同手机用户使用手机的击键特征。依据数理统计知识发现其符合正态分布,进而设计和实现了基于击键特征的手机用户身份认证系统。经测试表明,该系统能显著提高手机安全性。 相似文献
95.
带折痕的Loop细分曲面等距面处理算法 总被引:1,自引:0,他引:1
Loop细分曲面不同细分层次的网格面可作为不同加工工序的加工模型.现有等距面生成算法因未考虑折痕和边界的特殊情况,当折痕或边界存在时将会生成与预期结果有较大差别的等距面.给出了折痕等尖锐特征处极限等距位置的计算方法,以及根据尖锐特征点极限位置反求初始网格等距位置的Gauss-Jacobi迭代公式,并证明了其迭代收敛性.采用文中算法得到的等距网格面令人满意. 相似文献
96.
J. Ashkenazi 《Journal of Superconductivity》1995,8(5):559-562
The electronic structure of the high-T
c
cuprates is studied on the basis of large-U and smallU orbitals. Two types of charge carriers are predicted: (i) spinless polarons with a very small bandwidth; (ii) anomalous carriers of both charge and spin. The results are consistent with many anomalous properties of the cuprates. The spinless polarons undergo a CDW transition, and transitions between pair states of the two types of carriers provide the pairing mechanism.The author acknowledges stimulating discussions with participants of the workshop. Some numerical work was performed at the Florida State University Computing Center. 相似文献
97.
In the present article, higher-order shear and normal deformable plate theory together with modified couple stress theory are developed to study the bending analysis of thick functionally graded rectangular micro-plates. One material length scale parameter is used for capturing the size effects. Utilizing the variational approach and also a principle of virtual displacement, a new form of equilibrium equations and the corresponding boundary conditions are derived. It is assumed that material properties vary through the thickness according to the power law function. Finally, an analytical solution for the bending problem of a simply supported FG rectangular micro-plate is presented. 相似文献
98.
Most of the published literature on robust design is basically concerned with a single response. However, the reality is that common industrial problems usually involve several quality characteristics, which are often correlated. Traditional approaches to multidimensional quality do not offer much information on how much better or worse a process is when finding optimal settings. Köksoy and Fan [Engineering Optimization 44 (8): 935–945] pointed out that the upside-down normal loss function provides a more reasonable risk assessment to the losses of being off-target in product engineering research. However, they only consider the single-response case. This article generalizes their idea to more than one response under possible correlations and co-movement effects of responses on the process loss. The response surface methodology has been adapted, estimating the expected multivariate upside-down normal loss function of a multidimensional system to find the optimal control factor settings of a given problem. The procedure and its merits are illustrated through an example. 相似文献
99.
Tijn Borghuis 《Journal of Logic, Language and Information》1998,7(3):265-296
We present a framework for intensional reasoning in typed -calculus. In this family of calculi, called Modal Pure Type Systems (MPTSs), a propositions-as-types-interpretation can be given for normal modal logics. MPTSs are an extension of the Pure Type Systems (PTSs) of Barendregt (1992). We show that they retain the desirable meta-theoretical properties of PTSs, and briefly discuss applications in the area of knowledge representation. 相似文献
100.
M. Rajeswari S. Lakeou E. A. Wood D. D. Choughule T. Venkatesan K. S. Harshavardhan Z. Shi 《Journal of Superconductivity》1996,9(3):307-310
We present our studies of the low-frequency excess electrical noise in YBa2Cu3O7- thin films in the normal state. We have studied films with varying microstructure deposited on different substrates. The frequency dependence and bias current dependence of the noise power spectral density agree with the behavior expected for noise due to conductance fluctuations. Comparison between films on different substrates shows that the presence of defects such as grain boundaries in the film correlate with significantly enhanced noise levels. The noise levels in our good-quality epitaxial films are several orders of magnitude lower than the anomalously large noise magnitudes reported for YBa2Cu3O7- in most of the earlier studies. 相似文献