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981.
DUAN Shao-guang 《保鲜与加工》2004,(11):66-70
The contact number is an important mathematical tool of systems theory and methods in the monograph Set Pair Analysis and Its Preliminary Applications written by Zhao Keqin for unitizedly processing the uncertainties due to the fuzzy, stochastic, intermediate and information uncomplete about something. The article applies the multivector algebra which is isomorphism with the real Dirac algebra in the real space-time adopted by Venzo de Sabbata to the contact number of set pair analysis, and consequently, the contact number is generalized correspondingly. 相似文献
982.
Mathematical model of power frequency electric field is established based on Charge Simulation Method(CSM) to analyze power frequency electric field caused by EHV lines with overhead ground wires and its effect, which are entering the megalopolis. Calculative method on the electric field under the transmission lines is analyzed and validated. According to the criterion of environmental evaluation, the distributing characteristic of electric field is summarized, in case of various arrangement manners of lines. At last, some advice and methods of eliminating electric field under the transmission lines entering the megalopolis is proposed with regard to protecting environment. 相似文献
983.
984.
Based on the data of dynamic tests of small single-storey steel frames,the suitability of simplified hi-linear restoring force model in earthquake response analysis is discussed, and the Maximum displacement response MD, the sum of squares of the displacements in the whole vibrating history SSD, and the total dissipated energy EI are considered respectively as equivalent object. 相似文献
985.
In general, the process of synthesis the refractory nanoparticles Is classified as solid state, liquid state and gaseity. The new progress and development in the study of refractory nanoparticles are investigated. The synthesis technology of the refrectory nanoparticle in liquid state is discussed mostly. The refrectory nanoparticles is synthesized by the liquid state. The characteristics and the structure of the refrectory nanoparticles have been studied in this paper. 相似文献
986.
WU Pei-lin~ 《保鲜与加工》2004,(6):6-12
The rural urbanization process in Chongqing is much slower than that in other metropolitans and most of the provinces in eastern China, which can't adapt to its important function as the economic and cultural center in southwestern China.It is urgent for Chongqing to accelerate the rural urbanization for improving its whole urbanization level and speeding up its economy development to catch up with other metropolitans and some advanced provinces.Compared with the urbanization in other metropolitans and some provinces, the authors demonstrated the rural urbanization situation and its characteristics in Chongqing in details, analyzed the reasons for the poor urbanization and its influences on the social-economic development especially that in the rural area.Inferior position of Chongqing's small towns in the market competition with those from other provinces is one of the results of its poor urbanization development.At last, the authors suggested a few practical countermeasures to improve the rural urbanization in order to get a rapid and sustainable rural development and to increase the whole economic effects of the metropolitan. 相似文献
987.
988.
Cao Shugang 《保鲜与加工》1992,(3):128-133
Defferent forms of mechanical construction, the distribution of stress, and the process of the deformation destruction in the enclosing rocks in a working face of a pitching seam are analyzed according to its geological and mining specialities. 相似文献
989.
Liu Yuwen Liang Xichang 《保鲜与加工》1993,(1):64-66
Based on the infroduction of the present process of quenched internal gear, a new technolgy of machining quenched internal gear-EDM generating technology is presented with its principle and machining processes. . 相似文献
990.
Huang Wenzhen Huang Buyu Dong Xun 《保鲜与加工》1993,(1):72-77
Based upon the eigenvalue sensitivity theory of non-self-adjoit system and the component mode synthesis method,a new technique is developed to analyze the eigenvalue sensitivity to variation of parameters of large rotor-bearing system. As an application, the influence of the journal bearing parameters on the stability of a large domestic turbine-generator set is analyzed and discussed. 相似文献