On the basis of choosing the basic element as the bar and choosing the basic mesh as the triangle as well as supposing the conditions of the element, the membrane states of an antenna reflector were researched by the ...On the basis of choosing the basic element as the bar and choosing the basic mesh as the triangle as well as supposing the conditions of the element, the membrane states of an antenna reflector were researched by the analogue method, because the membrane effect was not omitted during the ending deployment process of the radial rib antenna. The expressions of the bar element’s section area and density were obtained, while the expression of the stress state during the ending deployment process of antenna was attained. During the establishment process of the analogue method, the analysis method of the net shell structure was employed. Moreover, during the backward deduction of membrane stress, the continuation method was adopted. Because the expression of the membrane stress state can realize the analysis on the antenna membrane state, this research has great significance of theoretical direction to the normal operation of the space deployable antenna.展开更多
Electro hydrodynamic analogue (EHA) method is applied to study the flow fields in the West Lake. It gives out a satisfactory result on water velocities and discharges of the bridge openings.
In this paper, an analogue correction method of errors （ACE） based on a complicated atmospheric model is further developed and applied to numerical weather prediction （NWP）. The analysis shows that the ACE can eff...In this paper, an analogue correction method of errors （ACE） based on a complicated atmospheric model is further developed and applied to numerical weather prediction （NWP）. The analysis shows that the ACE can effectively reduce model errors by combining the statistical analogue method with the dynamical model together in order that the information of plenty of historical data is utilized in the current complicated NWP model, Furthermore, in the ACE, the differences of the similarities between different historical analogues and the current initial state are considered as the weights for estimating model errors. The results of daily, decad and monthly prediction experiments on a complicated T63 atmospheric model show that the performance of the ACE by correcting model errors based on the estimation of the errors of 4 historical analogue predictions is not only better than that of the scheme of only introducing the correction of the errors of every single analogue prediction, but is also better than that of the T63 model.展开更多
Based on the characteristics of pile-soil interaction and the Mohr-Coulomb strength theory,a new method of determining the side friction at a pile-soil interaction is proposed.Combined with the actual engineering case...Based on the characteristics of pile-soil interaction and the Mohr-Coulomb strength theory,a new method of determining the side friction at a pile-soil interaction is proposed.Combined with the actual engineering cases,the effectiveness of the analogue test method is verified by comparing it with the traditional anchor pile method and self-balanced method.Taking the self-balanced test of the bridge pile foundation in the Songhua River as an example,the conversion factor of sandy soil and weathered mudstone are confirmed by the analogue test method.The results show that the conversion factor of sandy soil and weathered mudstone in the Songhua River area should consider the geological conditions and the construction technology,etc.The standard values are relatively conservative.It is suggested that the engineering application should be properly revised.The recommended range of the conversion factor of sandy soil in this area is 0.65 to 0.85,and that of weathered mudstone is 1.0.展开更多
基金Sponsored by the National Natural Science Foundation of China(Grant No.19682003)
文摘On the basis of choosing the basic element as the bar and choosing the basic mesh as the triangle as well as supposing the conditions of the element, the membrane states of an antenna reflector were researched by the analogue method, because the membrane effect was not omitted during the ending deployment process of the radial rib antenna. The expressions of the bar element’s section area and density were obtained, while the expression of the stress state during the ending deployment process of antenna was attained. During the establishment process of the analogue method, the analysis method of the net shell structure was employed. Moreover, during the backward deduction of membrane stress, the continuation method was adopted. Because the expression of the membrane stress state can realize the analysis on the antenna membrane state, this research has great significance of theoretical direction to the normal operation of the space deployable antenna.
文摘Electro hydrodynamic analogue (EHA) method is applied to study the flow fields in the West Lake. It gives out a satisfactory result on water velocities and discharges of the bridge openings.
基金Project supported by the National Natural Science Foundation of China （Grant Nos 40575036 and 40325015）.Acknowledgement The authors thank Drs Zhang Pei-Qun and Bao Ming very much for their valuable comments on the present paper.
文摘In this paper, an analogue correction method of errors （ACE） based on a complicated atmospheric model is further developed and applied to numerical weather prediction （NWP）. The analysis shows that the ACE can effectively reduce model errors by combining the statistical analogue method with the dynamical model together in order that the information of plenty of historical data is utilized in the current complicated NWP model, Furthermore, in the ACE, the differences of the similarities between different historical analogues and the current initial state are considered as the weights for estimating model errors. The results of daily, decad and monthly prediction experiments on a complicated T63 atmospheric model show that the performance of the ACE by correcting model errors based on the estimation of the errors of 4 historical analogue predictions is not only better than that of the scheme of only introducing the correction of the errors of every single analogue prediction, but is also better than that of the T63 model.
基金The National Key Research and Development Program(No.2017YFC0703408)the National Natural Science Foundation of China(No.51478109,51678145,51878160)
文摘Based on the characteristics of pile-soil interaction and the Mohr-Coulomb strength theory,a new method of determining the side friction at a pile-soil interaction is proposed.Combined with the actual engineering cases,the effectiveness of the analogue test method is verified by comparing it with the traditional anchor pile method and self-balanced method.Taking the self-balanced test of the bridge pile foundation in the Songhua River as an example,the conversion factor of sandy soil and weathered mudstone are confirmed by the analogue test method.The results show that the conversion factor of sandy soil and weathered mudstone in the Songhua River area should consider the geological conditions and the construction technology,etc.The standard values are relatively conservative.It is suggested that the engineering application should be properly revised.The recommended range of the conversion factor of sandy soil in this area is 0.65 to 0.85,and that of weathered mudstone is 1.0.
