A new method for MEMS dynamics analysis is presented,ased on the similarity theory. With this method, two systems' similarities can be captured in terms of physics quantities/governed-equations amongst different e...A new method for MEMS dynamics analysis is presented,ased on the similarity theory. With this method, two systems' similarities can be captured in terms of physics quantities/governed-equations amongst different energy fields, and then the unknown dynamic characteristics of one of the systems can be analyzed according to the similar ones of the other system. The probability to establish a pair of similar systems among MEMS and other energy systems is also discussed based on the equivalent between mechanics and electrics, and then the feasibility of applying this method is proven by an example, in which the squeezed damping force in MEMS and the current of its equivalent circuit established by this method are compared.展开更多
Multiconfigurational second order perturbation theory was employed in order to describe the ground and excited states of C60^-n. Different choices of the active spaces are discussed and the possibility to apply multic...Multiconfigurational second order perturbation theory was employed in order to describe the ground and excited states of C60^-n. Different choices of the active spaces are discussed and the possibility to apply multiconfigurational theory to study C12o is investigated. The calculations were performed for all possible spin states (for selected charge) and show the preference of low spin state. The energy difference between two C60^-3 and pairs C60^-1- C60^-5 and C60^-2- C60^-4 shows that the probability to create a charge alternation in fullerides is small.展开更多
The research and achievements made on seismic subsidence of loess,obtained over the past30 years,were reviewed.Seismic Subsidence of Loess(SSL)has been verified by microstructure characteristics,dynamic triaxial exper...The research and achievements made on seismic subsidence of loess,obtained over the past30 years,were reviewed.Seismic Subsidence of Loess(SSL)has been verified by microstructure characteristics,dynamic triaxial experiments,and in-situ explosion tests,and has become an important subject in the field of seismic loess engineering research.While,the research is still in the stage of theoretical study of saturated soil,and there are no representative cases of seismic subsidence of loess in historical earthquakes.It is difficult to express structure characteristics using microstructure morphology.While,soil mechanics are available methods for this.Seismic subsidence judgment is absolute in some certain value ranges for several parameters.Therefore,probabilistic judgment should be developed.The seismic subsidence ratio is estimated mostly by empirical formulas or semiempirical and semi-theoretical formulas,which are based on laboratory data.These formulas are not established on the basis of physical process and mechanics of seismic subsidence,and this leads to more variables,complicated computation,and poor practicability.To solve these problems,we need to distinguish the main factors and corresponding variables,to establish a mechanics model for seismic subsidence estimation,and to characterize its physio-mechanical process.The key of anti-seismic subsidence treatment is to reduce the seismic subsidence property of soils,and to lower the interaction between the soil body and underground structures.展开更多
A theoretical calculation of the nonrelativistic Lamb shift in nano-sized semiconducting (GaAs) and metallic (AI) circular rings is carried out. On the basis of a flat one-electron potential with infinitely high b...A theoretical calculation of the nonrelativistic Lamb shift in nano-sized semiconducting (GaAs) and metallic (AI) circular rings is carried out. On the basis of a flat one-electron potential with infinitely high barriers, the radiative back-action is obtained to second order in perturbation theory. Numerical results are presented for the radiative correction to the transition frequency between the ground state and first excited radial quantum states (initial state: (1,1,0), final state: (2,1,0)) neglecting the curvature term in the Schr6dinger equation. Lamb shifts are calculated as functions of the inner ring radius, the ring thickness, and the temperature.展开更多
文摘A new method for MEMS dynamics analysis is presented,ased on the similarity theory. With this method, two systems' similarities can be captured in terms of physics quantities/governed-equations amongst different energy fields, and then the unknown dynamic characteristics of one of the systems can be analyzed according to the similar ones of the other system. The probability to establish a pair of similar systems among MEMS and other energy systems is also discussed based on the equivalent between mechanics and electrics, and then the feasibility of applying this method is proven by an example, in which the squeezed damping force in MEMS and the current of its equivalent circuit established by this method are compared.
文摘Multiconfigurational second order perturbation theory was employed in order to describe the ground and excited states of C60^-n. Different choices of the active spaces are discussed and the possibility to apply multiconfigurational theory to study C12o is investigated. The calculations were performed for all possible spin states (for selected charge) and show the preference of low spin state. The energy difference between two C60^-3 and pairs C60^-1- C60^-5 and C60^-2- C60^-4 shows that the probability to create a charge alternation in fullerides is small.
基金sponsored by the Basic Research Foundation of Institute of Earthquake Science,China Earthquake Administration(No.2011IESLZ03)
文摘The research and achievements made on seismic subsidence of loess,obtained over the past30 years,were reviewed.Seismic Subsidence of Loess(SSL)has been verified by microstructure characteristics,dynamic triaxial experiments,and in-situ explosion tests,and has become an important subject in the field of seismic loess engineering research.While,the research is still in the stage of theoretical study of saturated soil,and there are no representative cases of seismic subsidence of loess in historical earthquakes.It is difficult to express structure characteristics using microstructure morphology.While,soil mechanics are available methods for this.Seismic subsidence judgment is absolute in some certain value ranges for several parameters.Therefore,probabilistic judgment should be developed.The seismic subsidence ratio is estimated mostly by empirical formulas or semiempirical and semi-theoretical formulas,which are based on laboratory data.These formulas are not established on the basis of physical process and mechanics of seismic subsidence,and this leads to more variables,complicated computation,and poor practicability.To solve these problems,we need to distinguish the main factors and corresponding variables,to establish a mechanics model for seismic subsidence estimation,and to characterize its physio-mechanical process.The key of anti-seismic subsidence treatment is to reduce the seismic subsidence property of soils,and to lower the interaction between the soil body and underground structures.
文摘A theoretical calculation of the nonrelativistic Lamb shift in nano-sized semiconducting (GaAs) and metallic (AI) circular rings is carried out. On the basis of a flat one-electron potential with infinitely high barriers, the radiative back-action is obtained to second order in perturbation theory. Numerical results are presented for the radiative correction to the transition frequency between the ground state and first excited radial quantum states (initial state: (1,1,0), final state: (2,1,0)) neglecting the curvature term in the Schr6dinger equation. Lamb shifts are calculated as functions of the inner ring radius, the ring thickness, and the temperature.