The paper presents process of creating a centrifugal pump rotor model in CAD environment. Modeling of a virtual object was divided into two stages, modeling of the efficient pump and the simulated failure of one of th...The paper presents process of creating a centrifugal pump rotor model in CAD environment. Modeling of a virtual object was divided into two stages, modeling of the efficient pump and the simulated failure of one of the impeller＇s blades. Comparison of the results of the resonance frequency obtained from the model analysis, with those obtained from measurements on the actual object was shown. Measurements and simulations were conducted on the pump before and after the simulated damaged of the rotor. In order to verify the model the rotor of pump was weighted and compared with the masses of the respective components obtained from the virtual object. In the second stage genuine rotor was subjected to the experimental modal analysis.展开更多
The optical properties of three linear conjugated oligomers （F-P, F-P-F, and P-F-P-F-P）, where phenothiazine （P） and fluorene （F） groups arrange alternately, are investigated. With the enhancement of the π-conj...The optical properties of three linear conjugated oligomers （F-P, F-P-F, and P-F-P-F-P）, where phenothiazine （P） and fluorene （F） groups arrange alternately, are investigated. With the enhancement of the π-conjugated system, their absorption and emission bands both gradually red shift, and their two-photon properties are also improved. Meanwhile, their fluorescence dynamic traces are analyzed with continuous rate distribution model, exhibiting that their decay rates gradually accelerate and the rate distribution width become narrower. The quantum chemical calculation offers their molecular structures and transition mechanism, showing that the enhancement of π-conjugated system should be responsible for tile improvement of two-photon properties.展开更多
Modeling the mean and covariance simultaneously is a common strategy to efficiently estimate the mean parameters when applying generalized estimating equation techniques to longitudinal data. In this article, using ge...Modeling the mean and covariance simultaneously is a common strategy to efficiently estimate the mean parameters when applying generalized estimating equation techniques to longitudinal data. In this article, using generalized estimation equation techniques, we propose a new kind of regression models for parameterizing covariance structures. Using a novel Cholesky factor, the entries in this decomposition have moving average and log innovation interpretation and are modeled as the regression coefficients in both the mean and the linear functions of covariates. The resulting estimators for eovarianee are shown to be consistent and asymptotically normally distributed. Simulation studies and a real data analysis show that the proposed approach yields highly efficient estimators for the parameters in the mean, and provides parsimonious estimation for the covariance structure.展开更多
The analytical forms of the interaction potentials between one pseudo-scalar/vector and one scalar/tensor/axial-vector heavy mesons are deduced based on a chiral quark model. Our results explicitly show the attractive...The analytical forms of the interaction potentials between one pseudo-scalar/vector and one scalar/tensor/axial-vector heavy mesons are deduced based on a chiral quark model. Our results explicitly show the attractive property between the two heavy mesons. Consequently, a series of possible molecular states are obtained. It is expected that our study might shed some light on the popular discussions of the newly observed XYZ states.展开更多
文摘The paper presents process of creating a centrifugal pump rotor model in CAD environment. Modeling of a virtual object was divided into two stages, modeling of the efficient pump and the simulated failure of one of the impeller＇s blades. Comparison of the results of the resonance frequency obtained from the model analysis, with those obtained from measurements on the actual object was shown. Measurements and simulations were conducted on the pump before and after the simulated damaged of the rotor. In order to verify the model the rotor of pump was weighted and compared with the masses of the respective components obtained from the virtual object. In the second stage genuine rotor was subjected to the experimental modal analysis.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China. （No.21103161. No.11274142, No.11304058, No.11274034. and No.11004080） and the China Postdoctoral Science Foundation （No.2011MS00927 and No.2013T60319）.
文摘The optical properties of three linear conjugated oligomers （F-P, F-P-F, and P-F-P-F-P）, where phenothiazine （P） and fluorene （F） groups arrange alternately, are investigated. With the enhancement of the π-conjugated system, their absorption and emission bands both gradually red shift, and their two-photon properties are also improved. Meanwhile, their fluorescence dynamic traces are analyzed with continuous rate distribution model, exhibiting that their decay rates gradually accelerate and the rate distribution width become narrower. The quantum chemical calculation offers their molecular structures and transition mechanism, showing that the enhancement of π-conjugated system should be responsible for tile improvement of two-photon properties.
基金supported by National Natural Science Foundation of China(Grant Nos.11271347 and 11171321)
文摘Modeling the mean and covariance simultaneously is a common strategy to efficiently estimate the mean parameters when applying generalized estimating equation techniques to longitudinal data. In this article, using generalized estimation equation techniques, we propose a new kind of regression models for parameterizing covariance structures. Using a novel Cholesky factor, the entries in this decomposition have moving average and log innovation interpretation and are modeled as the regression coefficients in both the mean and the linear functions of covariates. The resulting estimators for eovarianee are shown to be consistent and asymptotically normally distributed. Simulation studies and a real data analysis show that the proposed approach yields highly efficient estimators for the parameters in the mean, and provides parsimonious estimation for the covariance structure.
基金Supported by National Natural Science Foundation of China under Grant Nos.11105158,11035006,10975146,11261130,and 11475192Ministry of Science and Technology of China under Grant No.2009CB825200+1 种基金the Fundamental Research Funds for the Central Universities of Chinathe DFG and NSFC through Funds Provides to the Sino–German CRC 110"Symmetries and the Emergence of Structure in QCD"
文摘The analytical forms of the interaction potentials between one pseudo-scalar/vector and one scalar/tensor/axial-vector heavy mesons are deduced based on a chiral quark model. Our results explicitly show the attractive property between the two heavy mesons. Consequently, a series of possible molecular states are obtained. It is expected that our study might shed some light on the popular discussions of the newly observed XYZ states.
