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991.
The analysis of vibration response of structure with TMD is carried out under earthquake ,considering the ground-structure interaction. The varying rule of square difference of displacement of structure with the TMD on or off by changing the first inherent frequency is also presented .It has been proved by comparing and analyzing that a TMDstructure with optimum parameters can efficiently reduce the vibration of structure under strong wind and earthquake,when the main frequency of the ground motion is within the range of TMD vibration reducing frequency. 相似文献
992.
The exact computing of house architectural area and apportionment of area is strongly related to the actual interests of people. If it is done manually,there are many problem such as longer time spending, more workload, requiring detailed verification, nonstandard calculating report. Using ActiveX automation and ADO techniques, the house architectural area computing and plotting system was developed under Autocad R14 environment with VB 6.0 and Access database in order to solve above problem. The developed system can automatically compute house architectural area and apportionment of area for each floor of each building and can print the related data report and drawing. The system works well in many departments of house measurement. Several key technical problem of the system are discussed. 相似文献
993.
After the completion of the Three Gorges project,the navigation conditions of the reservoir region will be improved evidently,which has laid the foundation for straight run of the 10,000-ton-class fleet to Chongqing Port,and is the promotion of the development of shipping in Yangtze River.But according to the standard of the 10,000-ton-class fleet,there are still some reaches of the reservoir region can not meet the requirements of the waterway on smooth and safe navigation.Therefore,some regulation measures should be adopted to eliminate these obstructions.It is one of the important parts in the reservoir region waterway regulation work for the Fuling to Tongluo canyon reach blasting project.30 reef obstacle blocks of 14 reaches in this project were removed by blasting.Based on the analysis of obstruct features of various rocks,according to the standard of the 10,000-ton-class fleet,the design parameters and blasting regulation program were put forward,and the regulation effect is analyzed and forecasted. 相似文献
994.
You lihua Wu Huibi Sun Renbo Wang Daivu 《保鲜与加工》1992,(4):48-53
The basic equations of wall plates of MAN' S dry gas holders are derived in this paper. According to the law of cylindrical bending given by the finite element results .we derive some approximate formula calculating the deflection and stresses of the wall plates from the basic equations. Compared with the known approximate calculating method.the method car. obviously increase the percision. 相似文献
995.
Zhang Caian Mo Lilong Lu Zhiwen 《保鲜与加工》1992,(6):128-131
This paper discuss the effects of automatic plug mills in small seamless tube mills. Far from traditional ideas,the auther comes rp with mew ideas, which adot the mew process of replacing rolling by piercing,a huge sum of economical interests and great social benefits will be gained. 相似文献
996.
The paper analyzes the difference of the pathogenic varieties and the relationship of the variety composition,allording to the historic material to the varieties of the main hybid fece varieties in Southeast Sichuan during 1992 to 1998.It's the first time to advance to use the camparison on rate of pathogenic isolates between norm and refrieving to define the susceptible extent of the varity.It's an scientific base to adjust the structures of the vartieties,to reach the objective of the macroscopic regulating to rice blast. 相似文献
997.
SUN Rong-hen 《保鲜与加工》2001,(2):127-131
This paper studies asymmetric exhaustive service polling system with Bernoulli feedback,gives the distributions of queue lengths and sojoun times,and obtains some other results,in stationary condition. 相似文献
998.
Zhao Changfu Feng Xiangui Li Yulan 《保鲜与加工》1991,(6):115-118
Calculations and analyses are made with the CVDA, IIW, JWES standards for the strength and welding defects of two spherical tanks of natural gas in CHONG QING. The results of the analyses indecate that though there are some problems with the welding quality in these tanks, they may still be used with the desingned presure. Now the formal working of these two spherical thanks has verified of the validity the calculations and analyses. 相似文献
999.
1000.
He Zonglu Duan Yurong 《保鲜与加工》1990,(5):98-105
The productive forces distribution model with entropy constraint is established. it satisfies both the demand with minimization of total cosls and the other demands with optimum distribution at a certain level. The model's regular optimal solution is a gravity molel.. 相似文献