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991.
Fracture mechanism is pertinent to minimize the catastrophic failures and optimize the structural design. An exact treatment on the electromagnetic permeable crack problems in a magnetoelectroelastic medium is presented by establishing a Hamiltonian system in terms of the symplectic eigenfunctions. The coefficients of the series are determined from the lateral boundary conditions at the crack surfaces and the outer boundary conditions along the geometric domain. Analytical formulations of intensity factors and distributions of dual variables are obtained by the symplectic expansion method. The various intensity factors are directly related to the first few terms of the non-zero eigenvalue solutions. 相似文献
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996.
T. A. Arkhangelskiy 《Automatic Documentation and Mathematical Linguistics》2012,46(2):118-123
Four electronic corpora created in 2011 within the framework of the “Corpus Linguistics: the Albanian, Kalmyk, Lezgian, and Ossetic Languages” Program of Fundamental Research of the RAS are presented. The interface and functionalities of these corpora are described, engineering problems to be solved in their creation are elucidated, and the promises of their development are discussed. A particular emphasis is made on the compilation of dictionaries and automatic grammatical markup of the corpora. 相似文献
997.
This paper considers the issues of forming a fuzzy database and ensuring its fullness and consistency. In addition, a certain method of designing the database structure using an hierarchical system of linguistic rules is suggested. 相似文献
998.
T. Hahn 《Computer Physics Communications》2012,183(3):460-469
MathLink is Wolfram Research?s protocol for communicating with the Mathematica Kernel and is used extensively in their own Notebook Frontends. The Mathematica Book insinuates that linking C programs with MathLink is straightforward but in practice there are quite a number of stumbling blocks, in particular in cross-language and cross-platform usage. This write-up tries to clarify the main issues and hopefully makes it easier for software authors to set up Mathematica interfacing in a portable way. 相似文献
999.
J. Sch?nenberger T. Momose B. Wagner W. H. Leong V. R. Tarnawski 《International Journal of Thermophysics》2012,33(2):342-362
Forty Canadian soils were laboratory tested for the presence of quartz and other minerals using X-ray diffraction/X-ray fluorescence techniques. On average, the highest quartz content was observed in soil samples from sites in Nova Scotia followed by Prince Edward Island sites, whereas soil sample from British Columbia sites had the lowest quartz content. The second most abundant mineral was albite that mainly occurred in soil samples from Ontario and Quebec sites. Illite was the third most abundant and prevailed in soils mainly from British Columbia and New Brunswick sites. Soil samples from British Columbia sites had the highest combined clay and silt content and were composed of illite, albite, kaolinite, and chlorite. The lowest clay content was found in the samples from the Quebec sites. The highest microcline (a potassium feldspar) content was observed in Quebec, Ontario, and Prince Edward Island sites. In contrast to other provinces, samples from Quebec and Ontario sites also included amphibole. Soil samples from Saskatchewan and Manitoba sites also comprised carbonates, i.e., calcite and dolomite. Iron oxides (e.g., goethite) were present in all soils, except the Quebec sites, but their occurrence was rather insignificant. 相似文献
1000.
Purification of cadmium by selective volatilization in vacuum in presence of oxide phase on its melt
Purification of cadmium in the presence of a thin (~0·001?mm) oxide layer on the surface of the molten metal was carried out using a simple system designed and fabricated locally. The analytical results revealed that the distillation through oxide layer gave better separation for Co, Ni, Cu, Zn, Ag, Sn, Hg and Tl, when compared to the distillation without oxide layer. This was attributed due to the impurity metal oxide phases formation on the surface of the molten metal. The influence of oxygen flow time on the distillation rate of cadmium was established. There was no excess oxygen (O) retained in the distillate after two consecutive vacuum distillations through oxide route. The experiments were conducted at the level of nearly 1·5?kg a batch to study the impurities behaviour due to upscaling. The detailed chemical analysis of 58 impurity elements in Cd in presence and absence of oxide layer was carried out by glow discharge mass spectrometry (GDMS). 相似文献