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991.
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
992.
Adopting the element SOLID65 and LINK8 in the general finite element analysis software ANSYS and fiber model beam-column element based on finite element flexibility method respectively, the comparative analysis of the cross, L and T-shaped RC columns under compression, bending, shear and torsion with flange width-thickness ratio of 4:1 is carried out. The applicability of plane section assumption in the nonlinear analysis is discussed primarily, which shows that it is feasible on the whole for shaped RC columns with flange width-thickness ratio equal to or smaller than 4:1. 相似文献
993.
In this paper the problem of energy consumption and environment in the birdhouse is introduced and the reconstructive measures aiming at energy savings are recommended. The measures include the limitation of temperature region, reconstruction of the building envelop and using the sunny board at the south side of the birdhouse roof. Finally, the energy efficiency of the reconstructive project is estimated. 相似文献
994.
This paper empirically discusses the mechanism of China Neutral Technology by Embodied Spillovers from North America, and the effect on China economic growth. The simulations show that the effects of technology spillovers on both the innovating and the receiving economies depend on SS and AC. The three sectors spillovers of North America can improve China's Hicks-neutral technological progress, but only the third industry can increase the output of same industry of China, and decrease the output of other two industries. Based on the simulations, some advices are given on China trade policy. 相似文献
995.
In the past, the criterion for calibration has almost invariably been the stellar oriented ballistic camera,the method is a point to point comparison on the identical coordinate system. Deficiencies is follows: The request of weather is severe(cloudless night); The period is often long; the measure equipment of high precision can't be calibrated. While EMBET methods is used in calibration, it does not need criterion and it demands only that the measure elements is larger than 3,and the trajectory and many system errors of the measure elements can be simultaneously calculated with the measure data sequences. The error models of related equipments' measure elements and the EMBET of typical equipment group are given. The EMBET method is successfully used in Accuracy-analysis of Satellite Launch. 相似文献
996.
Bill of material of product is data about product structure, and plays an important role in product information management. The paper analyzed characteristics of product BOM, and put forward a product BOM management method based on single layer BOM, witch can well meet requirements of product BOM. 相似文献
997.
It is important for enterprises' inventory management to find out the optimal production cycle and the length of shortage time,so that the total cost of inventory system can be reduced and the service level can be raised.Based on the classical EPQ model,this paper develops an EPQ model for deterioration items with different lost sale factor relative to the inventory level during shortage period.The existence of unique optimal solution is discussed by mathematic analysis and a numeric example.The sensitivity analysis shows that the parameter of losing sale has different impact on the costs of inventory system.The factors must be considered for the production inventory system to make management decision. 相似文献
998.
Fingerprint classification can provide an important indexing mechanism in a fingerprint database. An accurate and consistent classification can greatly reduce fingerprint matching time for large database. In the paper, by combining genetic algorithm and neural network is presented a fingerprint classification algorithm which is able to achieve an accurate classification. By inputting the global feature represented by directional image to three layer neural network trained by genetic algorithm, the fingerprints were classified into six categories: whorl, right loop, left loop, arch, double loop and undiscerning type successfully. 相似文献
999.
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
1000.
In this paper the working principle and performance character of both the manual and automatic Vicat apparatuses in existence are compared and analyzed,and their existing weakness and the urgent problem to be solved are pointed out.On this basis,adopting the technology of mechatronics and modern sensors,a new sort of full automatic Vicat apparatus that can fully satisfy the national standard in testing the setting time of the cement has been developed.This apparatus can be operated expediently with high precision,the test results are to be analyzed and computed automatically.This paper presents the working principle,performance character,key technology and prospect of application for the full automatic Vicat apparatus. 相似文献