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271.
272.
介绍了Web2.0的含义以及相关技术,并分析了播客、P2P流媒体、SNS等新媒体形态的特点和形式,并针对各媒体形式的特征、对于其市场发展和对未来的影响进行了探讨。 相似文献
273.
提出了一种从UML2.0序列图产生软件安全测试用例的方法,该方法以基于模型的测试技术为基础,将序列图转换为事件迁移图,从而产生测试用例集,提高了软件安全性测试的自动化水平.该方法可应用于软件设计与开发过程的早期阶段.所添加的UML2.0序列图的新特征,可将传统的软件测试方法应用于软件安全性测试. 相似文献
274.
为了方便用户直观明了地观测光电转换状态,在Microsoft Visual C+ 6.0和MFC等开发环境下设计开发了一个光静态散射上位机软件。上位机软件运用USB 2.0标准的接口芯片与下位机进行通信,可实现设备的打开、关闭以及数据的接收、解析、存储、显示等,还可实时绘制状态参数曲线以监测光电转换状态。详细介绍了该上位机软件的工作原理、结构、功能和特点,实际应用表明该软件具有良好的稳定性、完善的功能性和友好的操作界面等优点,可以满足光静态散射系统的需求。 相似文献
275.
The semirestricted non-primitive mean spherical approximation (npmsa) is used in combination with the PC-SAFT equation of state to model completely dissociating aqueous alkali halide systems. The salts are described using ion-specific parameters from tables and correlations. Upon analyzing aqueous electrolyte systems at infinite dilution of the salt it was concluded that for the arithmetic mean ion diameter of anion and cation, the semirestricted npmsa contribution gives no reliable results. Therefore, this parameter is adjusted in this work. The model was applied to aqueous alkali halide systems up to the solubility limit at T = 298.15 K. Mean ionic activity coefficients and osmotic coefficients were correlated with good results. The model was subsequently applied to temperatures up to T = 373.15 K and compared to liquid densities and to system pressures up to the solubility limit of the salts in water. The agreement between experimental data and the proposed equation of state is satisfactory for the liquid densities and excellent in case of the system pressures. 相似文献
276.
We present a formulation of deformed oscillator algebra which leads to intermediate statistics as a continuous interpolation between Bose-Einstein and Fermi-Dirac statistics. It is deduced that a generalized permutation or exchange symmetry leads to the introduction of the basic number and it is then established that this in turn leads to the deformed algebra of oscillators. We obtain the mean occupation number describing the particles obeying intermediate statistics which thus establishes the interpolating statistics and describe boson-like and fermion-like particles obeying intermediate statistics. We also obtain an expression for the mean occupation number in terms of an infinite continued fraction, thus clarifying successive approximations. 相似文献
277.
The distributions of returns for stocks are not well described by a normal probability density function (pdf). Student’s t-distributions, which have fat tails, are known to fit the distributions of the returns. We present pricing of European call or put options using a log Student’s t-distribution, which we call a Gosset approach in honour of W.S. Gosset, the author behind the nom de plume Student. The approach that we present can be used to price European options using other distributions and yields the Black-Scholes formula for returns described by a normal pdf. 相似文献
278.
We show that the dependence of the total energy of the atoms on their atomic number can follow a q-exponential (as proposed by C. Tsallis), for practically all elements of the periodic table. The result is qualitatively explained in terms of the way the atomic configurations are arranged to minimize energy. 相似文献
279.
280.
Newly obtained data on the critical dynamics of the drifting/fracturing sea ice in the Arctic Ocean were analyzed and compared with published data on the dynamic processes in the Earth’s crust. Substantial similarities were found in the scaling behavior of both geophysical systems; the most important of them is the b-value space/time variability including a pre-failure drop of this parameter. The b-value pattern of the ensemble of drifting ice floes is an analogue of the b-value distribution over areas and depths in tectonic structures. A common feature of the pre-failure state in the cryosphere and in the Earth’s crust is the increased degree of the energy conservation that manifests itself both in the sea ice consolidation prior to basin-wide ice pack fragmentations, and in involving harder geological formations in the fracture process before earthquakes, respectively. From the viewpoint of the conservative SOC concept, this relation between the system’s conservativity and the occurrence of large-scale fracture events means that the expected scale level of failure is determined by the system’s closeness to “true” SOC behavior. 相似文献