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81.
The group of Mid - mini enterprises under mass - economy is the intermediate organization built up by specialized division of work and cooperation. This kind of organization is flexible in operation with high efficiency, but difficult in development of new technology. On the basis of analyzing the character and deficiency of the mid - mini enterprises, in this paper, through providing a framework of information service platform for the mid - mini enterprises to enhance their creative ability and complex competition. The construction and operational strategy of such platform are investigated. Finally a successful case study is given. 相似文献
82.
83.
In this paper,solidifinG ladle of hot metal has been studied from the point ofview of heat transfer.A mathematical model,which is applied to predict the shape and the thicknessof solidifing layer,has been developed. The theoretical calculated results agree with the appliedresults in preduction. The effects of various paramenters,such as the circulating times, the inner-surface temporature of ladle and the different refractories,on the shape and the thickness ofsolidifing layer have been discussed.These are contributed to reduce the solidifing ladle of hot metal. 相似文献
84.
Li Yourong Jin Mingcong Tang Jingwen 《保鲜与加工》1993,(6):46-50
The concept of loss rate of available energy was introduced for evaluating heat exchanger performance. At the same time, the general expression of loss rate of available energy was obtained for heat exchangers of several typical. And NL criteria was recommended for evaluation of the loss rate of available energy of heat exchanger. Then. the influences of inlet temperatures ratio, heat capacity ratio of fluids, the number of heat transfer units and flow patterns of heat exchanger on ,VL criteria were also discussed. 相似文献
85.
Gu Qiankun Tang Yike Yu Youju Xie Zhijiang Liang Xichang 《保鲜与加工》1997,(6):96-102
The dynamic characteristic of active isolation atuator on flexible foundations was studied under the installation of parallel structure and foundation cancellation.The influencing relationships between active isolation force of the different installation ways and passive isolation system and flexible foundation were analyzed and compared.Scientific basis for selecting installation ways of active isolator is provided in this paper. 相似文献
86.
He Yaosan Lin Jingdong Tang Zhuoyao Tong Mingru 《保鲜与加工》1995,(5):7-12
In this paper, the excitation principle and operating characteristics ofasynchronized turbogenerators are analyzed,and adaptive tracing iterative control strategy based on state identification is proposed. In order to apply this control scheme to practice engineering, some primary elements are analyzed and presented for constituting dual-channel automatic excitation control system of asynchronized turbogenerators. Finally, the paper presents the principle structure charts about excitation control system of asynchroized turbogenerators. 相似文献
87.
Load dynamic matching of supply and demand side based on the utilization of urban sewage heat energy
Flowing dynamic characteristics and its temperature dynamic characteristics of a three-level sewage pipe network in Chongqing were analyzed. A mall's building whole year load was simulated. In the adverse condition of wastewater flow, the market construction peak discharge heat was compared with the sewage heat load, the balance between the most adverse flow and the building demand was found. Explored supply and demand matching method between urban sewage and city building load in flow adverse condition to take full advantage of the urban sewage cold and hot resources. the composite system was adeptcd to make up the most unfavorable flow time of sewage average heat load and the construction load difference; it also puts forward principle of load sharing and control strategy aimed at compound system. 相似文献
88.
为得出直墙拱形巷道围岩应力分布规律,应用复变函数弹性理论推导了直墙拱形巷道围岩应力分布的解析表达式。对直墙拱形巷道边界的围岩应力和巷道水平线方向的围岩应力分布规律进行分析,并考虑直墙拱形巷道断面高宽比和侧压系数对其影响规律。研究表明:在不同巷道断面高宽比、侧压系数下,直墙拱形巷道围岩应力集中区域主要集中在直墙底部底角处、拱形顶板中点附近和底板中部3个位置。不同巷道断面高宽比下,直墙拱形巷道沿水平线的应力分布规律基本相同。侧压系数大于1时,采用巷道断面高宽比小于1较有利于巷道稳定;侧压系数小于等于1时,采用巷道断面高宽比大于1较有利于巷道稳定。 相似文献
89.
90.
Liu Li Tang Janxin 《保鲜与加工》1995,(5):113-119
In this paper the author' s study on the monitoring measurement technique of NATM,the regularity and conditions of the country rock deformation are analysed based on the site measurement data in the west section of Zhongliangshan tunnel. The regression analysis of measure data for different measure lines of vavious country rock is done by the use of self-compiled CRAP program. The stability criterion for various rockmass and optimum time for primary and permanent support are provided. The conclusion available could conduct the theoretical research of NATM deeply as well as tunnel design and construction. 相似文献