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891.
The effect of the electromotive force arising in combustion of heterogeneous systems with condensed products is explained. A convective mechanism of arising regions with different charge densities due to charge transfer by the gas filtered in the pores is formulated on the basis of the developed physical concepts, estimates, and analysis of experimental data. Key words: combustion, electron emission, filtration, electromotive force.  相似文献   
892.
893.
The results of X-rays, electrical resistivities and magnetic studies performed on Yx Zr x Ba2Cu3Ot7−δ and Y1−2x Zr x Eu x Ba2Cu3O7−δ superconducting compounds, in the temperature range 4.2–500 K and external fields up to 50 kOe are reported. The presence of zirconium decreases the superconducting transition temperatures,T c. BelowT c, the hysteresis loops narrow when the zirconium content increases. From the magnetization curves, the critical current densities were determined. A time dependence of the magnetizations of logarithmic form was found. The flux-pinning energy was estimated to beU ≃0.03 eV. Above the transition temperatures, Yx Zr x Ba2Cu3Ot7−δ samples show a Pauli-type paramagnetism, while Y1−2x Zr x Eu x Ba2Cu3O7−δ compounds have, in addition, temperature-dependent contributions to the magnetic susceptibilities. The effective europium moments are ∼3.40 μB suggesting that the ion is in (+3) valence state.  相似文献   
894.
Pham  V.D. Vu  T.B. 《Electronics letters》1998,34(5):427-428
The authors present an adaptive space-time reduced-length minimum mean-squared error (MMSE) receiver to suppress co-channel interference in the near-far environment for an asynchronous direct-sequence code-division multiple-access (DS/CDMA) system. Simulation results show that better bit-error rate and faster and more stable convergence are achieved over the existing full- and reduced-length MMSE receivers  相似文献   
895.
896.
The paper describes the development of a software design aid for use at the conceptual stage of engineering design. It is intended for use in the design of mechatronic products but has wider potential uses. Early approaches were based on function structures and tables of options and the system that evolved allows the assembly of schemes linked by matching their input and output ports. A database of components is provided which can be accessed via different indexes and the designer can easily create and compare alternative schemes at the concept stage.A bond graph approach is used to define the interconnections between components. This allows correct port matching but also provides for future development such as constraint propagation through the design and links to simulation tools.  相似文献   
897.
898.
A method for identifying a set of candidate words that matches well with a given utterance is discussed. The method uses precomputed groups of acoustically similar words. Given a vocabulary, for each word a short list of words that are acoustically similar to it is computed. These groups are constructed using training utterances recorded by several speakers and used in an isolated utterance recognition system to construct candidate word lists during recognition. Experiments show that the correct word appears on the short list of candidate words constructed during recognition using this scheme over 98% of the time  相似文献   
899.
The matrix pencil (MP) method, based on the singular value decomposition (SVD), is applied to quantitative NMR spectroscopy. Its relationship to other SVD-based methods is also presented. Simulations and applications are given to demonstrate the capability of superior performance.©1993 John Wiley & Sons Inc  相似文献   
900.
Institute of Rock Mechanics, Academy of Sciences of the USSR, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 39–44, January-February, 1992.  相似文献   
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