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141.
This paper summarized the recent research results about the durability of structures, introduced their current application in durability design, appraisal, estimation of rest life and strategy of maintenance and strengthening as well as in other fields. 相似文献
142.
According to the graphics characteristics of metallic doors & windows design and based on the research of graphics dimension restriction problems. This paper provides a new method for parameterized design of metallic doors & windows in virtue of expression solution. In this method, the restrictions of graphic elements have been changed into the parameter expressions of sizes and positions of graphic elements. Through the calculation of such expressions, the parameter driven method has been reached. Thus the parameterization of graphics can be easier and quicker than before. It can be used to setup the open parameterized graphics libraries. 相似文献
143.
WU Wen xue 《保鲜与加工》2001,(5):124-129
For the stability analysis of the reinforced earth retaining wall with cohesive backfill, this paper assumes that the state of failure surface is circular sliding surface and the bearing capacity is straight line relation with capacity and length of the reinforcement strip. These formulas agree with actual state of the reinforced earth retaining wall with cohesive backfill and result in saving reinforcement material in the design. 相似文献
144.
In this paper,notions on appropriate technology for the Steel Construction Congregated Apartments are proposed in order to deal with the technical impediment that arises from applying steel structural techniques to the congregated apartments.The appropriate technology for the steel construction congregated apartments is defined as systematic technologies that are in harmony with the status quo of Chinese productive force level,social culture and building technology,and as the strategies of choosing or balancing technology according to sustainable development principle.The principal design and constructing strategies of appropriate technology are as follows:(1) organization of residential space combined with steel construction techniques,(2) suitable structural system,(3) a new idea of fire resistance,and(4) kit building technique etc.A technological concept analysis about an ideal model of a steel construction system congregated apartment combined with the appropriate technology is also presented. 相似文献
145.
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147.
Valuation based on the bill of quantifies will change the existing valuation mode of tender and bidding. For the standardized management of tender and bidding for power projects and the inteUigentized information management of power enterprises, it is an inevitable trend of reform to apply the valuation mode based on the bill of quantifies. According to the characteristics of power projects, this paper expounds the working process of the valuation mode based on the bill of quantities and analyzes the goal and function need of the tender and bidding management system. Considering the calculation procedure of the valuation and the quote strategy of quantities bill, the composition of fees for the valuation is settled and the calculation method is designed. To establish the management system of tender and bidding with a valuation based on the bill of quantities is beneficial for the costing reform of power projects and the perfection of the tender and bidding market. Therefore it is of great significance to spread the new management mode of project costing with a valuation based on the bill of quantities. 相似文献
148.
Chen Qigao Feng Ya 《保鲜与加工》1993,(1)
This paper analyses the thermal moist characteristics of the hull layer beside an air layer at lower temperature in an envelope for a cold storage and presents a new method of waterproof by air layer. With test data from engineering practice, the theory on the barrier of self moisture proof at the surface sublayer of the hull layer in an attic on a cold storage is proven. The dried zone about three phase point is confirmed. It is a new knowledge for thermophysics on thermal design of a cold storage with an optimum thermal performance. 相似文献
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