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61.
Vague值向Fuzzy隶属度转化方法的准则 总被引:5,自引:4,他引:1
引入从Vague值A(u)导出的Vague值A軒(u)、赞成与反对程度、可能的不确定度、可能的赞成与反对程度等概念,应用这些概念提出两种把Vague值转换成Fuzzy隶属度的方法,提出判断Vague值转化为Fuzzy隶属度的准则,证明四种“转化”方法满足这些准则。 相似文献
62.
介绍了用Authorware扩展函数库alTools.u32实现Authorware多媒体课件全屏播放的方法 ,并通过一个实例详细讲解了其实现过程 相似文献
63.
S. Bradbury 《Journal of microscopy》1989,155(3):281-305
The pioneering seventeenth-century work of Hooke (using the compound microscope) and Leeuwenhoek (using the simple microscope) was followed in the eighteenth century by a period of comparative stagnation until the early nineteenth-century work of Lister (who evolved the principle of aplanatic focal points in lens design). The founding of the Microscopical Society of London in 1839 reflected the increasing importance of the microscope as a scientific instrument and its involvement in specimen preparation techniques, cell theory and bacteriology is described. The pursuit of increased resolving power—in particular the development of apochromatic lenses by Abbe and Zeiss and enhanced contrast techniques—polarized fight, u.v. microscopy, u.v. absorption and fluorescence, phase contrast and the differential interference contrast techniques, etc., are discussed. The story of microscopy in the twentieth century is one of interlocking discoveries and advances and the techniques of epi-illumination in scanning fluorescence microscopy, video acquisition and analyses of images in digital form and confocal scanning microscopy are surveyed. It is concluded that these techniques have opened up whole new areas for the future development of light microscopy. 相似文献
64.
65.
P. W. J. Van Eetvelt S. J. Shepherd S. K. Barton 《Wireless Personal Communications》1995,2(1-2):87-96
This paper presents the results of a preliminary investigation into the distribution of peak factors in the QPSK message space for different numbers of carriers with the aim of determining those messages which exhibit a low peak factor relative to a given threshold. A group structure is suggested which associatescosets of 16 messages intoequivalence classes having the same peak power. Algorithms for finding the members of cosets and equivalence classes are given. These messages are then rank ordered by peak power to show how a suitable code could be derived. It appears that allocating just one or two bits of redundancy to such a code will be sufficient to achieve substantial reductions in peak factor. 相似文献
66.
Rajni Sharma J. V. Yakhmi A. Sequeira B. A. Dasannacharya 《Journal of Superconductivity》1995,8(1):163-167
A 1201-phase superconductor (Pbub>0.5ub>Cuub>0.5ub>)SrLaCuOub>5±u35157730/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0">
ub> exhibiting a zero-resistance (R=0) state at 21 K has been synthesized. Neutron Rietveld refinement of the structure shows substantial oxygen disorder in the (Pb/Cu)-O(3) monolayer and excess occupancy of oxygen at the O(3) sites. The superconducting behavior of (Pbub>0.5ub>Cdub>0.5ub>)SrLaCuOub>5±u35157730/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0">
ub>, prepared under identical conditions, yields a value ofT
ub>
c
ub> (R=0) equal to 24 K. The presence of extra oxygen appears to be responsible for trapping of holes within the rock-salt (Pb/Cu)-O(3). 相似文献
67.
Ultrahigh vacuum studies indicate that the mechanism of the NO-CO reaction on Rh(111) involves reversible adsorption of NO and CO, NO decomposition, nitrogen desorption, and a Langmuir-Hinshelwood reaction between CO and oxygen. Employing available experimental data for the rate constants of these steps, we have calculated the steady-state reaction kinetics in a wide range of pressures and temperatures. At relatively high pressures (P
ub>NOub>u7768r4404075301/xxlarge8776.gif" alt="ap" align="MIDDLE" BORDER="0">P
ub>COub>u7768r4404075301/xxlarge8776.gif" alt="ap" align="MIDDLE" BORDER="0">0.01 bar), the results of simulations are in marginal agreement with the experimental data. Analyzing the difference between the theory and experiment makes it possible to understand the type of changes which might be introduced into the model in order to improve the agreement with the experiment. 相似文献
68.
Performance,cognitive load,and behaviour of technology‐assisted English listening learning: From CALL to MALL
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Chi‐Cheng Chang Clyde A. Warden Chaoyun Liang Pao‐Nan Chou 《Journal of Computer Assisted Learning》2018,34(2):105-114
This study examines differences in English listening comprehension, cognitive load, and learning behaviour between outdoor ubiquitous learning and indoor computer‐assisted learning. An experimental design, employing a pretest‐posttest control group is employed. Randomly assigned foreign language university majors joined either the experimental group (outdoor ubiquitous learning), with 80 participants (26 males and 54 females), or a control group (indoor computer‐assisted learning), with 80 participants (27 males and 53 females). The experiment lasted 3 weeks. Both groups were administered a test of English listening proficiency before and after the experiment along with a questionnaire of cognitive load postexperiment. Prior English listening proficiency forms a covariate for the multivariate analysis of covariance. Results show (a) students in the experimental group exhibit significantly better English listening comprehension after the experiment compared to the control group; (b) students in the experimental group reported significantly lower cognitive load than the control group; (c) English listening comprehension and cognitive load exhibited a statistically significant negative relationship; and (d) outdoor ubiquitous learning enhanced self‐reported learning interests and interactions more than indoor computer‐assisted learning. Contributions and significances of this study are presented based on these results. Finally, implications for teaching practices are proposed. 相似文献
69.
A thermo‐hydro‐mechanical model for multiphase geomaterials in dynamics with application to strain localization simulation
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T. D. Cao L. Sanavia B. A. Schrefler 《International journal for numerical methods in engineering》2016,107(4):312-337
In this paper, the non‐isothermal elasto‐plastic behaviour of multiphase geomaterials in dynamics is investigated with a thermo‐hydro‐mechanical model of porous media. The supporting mathematical model is based on averaging procedures within the hybrid mixture theory. A computationally efficient reduced formulation of the macroscopic balance equations that neglects the relative acceleration of the fluids, and the convective terms is adopted. The modified effective stress state is limited by the Drucker–Prager yield surface. Small strains and dynamic loading conditions are assumed. The standard Galerkin procedure of the finite element method is applied to discretize the governing equations in space, while the generalized Newmark scheme is used for the time discretization. The final non‐linear set of equations is solved by the Newton method with a monolithic approach. Coupled dynamic analyses of strain localization in globally undrained samples of dense and medium dense sands are presented as examples. Vapour pressure below the saturation water pressure (cavitation) develops at localization in case of dense sands, as experimentally observed. A numerical study of the regularization properties of the finite element model is shown and discussed. A non‐isothermal case of incipient strain localization induced by temperature increase where evaporation takes place is also analysed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
70.
The effect of u.v. radiation on the product distribution of the acid-catalysed depolymerization reaction of a lignite (C, 66.9wt%) has been investigated. The products are separated by solvent extraction and silica gel chromatography and their up>1up>H n.m.r. spectra and molecular weights are also measured. Larger amounts of solubilized material are formed in the u.v.-irradiated depolymerization experiments due to a greater amount of phenol incorporation in the reactions. The relative molar masses of products are lower than those obtained from thermal depolymerization experiments and they contain less hydroaromatic structures connected by fewer methylene bridges. It is suggested that u.v. radiation is making the coal more accessible for phenol in the depolymerization reactions. 相似文献