A bimorph piezoelectric beam with periodically variable cross-sections is used for the vibration energy harvesting. The effects of two geometrical parameters on the first band gap of this periodic beam are investigate...A bimorph piezoelectric beam with periodically variable cross-sections is used for the vibration energy harvesting. The effects of two geometrical parameters on the first band gap of this periodic beam are investigated by the generalized differential quadrature rule （GDQR） method. The GDQR method is also used to calculate the forced vibration response of the beam and voltage of each piezoelectric layer when the beam is subject to a sinusoidal base excitation. Results obtained from the analytical method are compared with those obtained from the finite element simulation with ANSYS, and good agreement is found. The voltage output of this periodic beam over its first band gap is calculated and compared with the voltage output of the uniform piezoelectric beam. It is concluded that this periodic beam has three advantages over the uniform piezoelectric beam, i.e., generating more voltage outputs over a wide frequency range, absorbing vibration, and being less weight.展开更多
In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the...In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the spaces of Lipschitz continuous functions. It has also been proved that the space of fractional integration,the space of Lipschitz continuous functions and the Sobolev space are identical in L^2-norm.Results obtainedhere are not true for fractional integrals(or Riesz potentials)in R^n.展开更多
Some building components are responsible for achieving more than one environmental function, these functions are usually of different requirements that can never be done by the same actions, and they are usually conne...Some building components are responsible for achieving more than one environmental function, these functions are usually of different requirements that can never be done by the same actions, and they are usually connected to changeable internal and external environment characteristics that vary among them. Minimizing the conflict of achieving the different environmental functions is an important challenge for all designers. Achieving a continuous thermal and optical comfort in an internal building space using the same window is an example of this challenge, as they have different requirements that may be sometimes contrary. It should be notable that there are a lot of recent technologies that may be used to find solutions for such a conflict. The Environmental Assessment Methods of Buildings appeared to set the principles of the optimum relation between buildings and their environment, they also could be used to encourage designers to reach the best environmental relations, and award them by main or additional assessment points. The research paper proposes to use the Environmental Assessment Methods of Buildings to assess the building ability of minimizing its environmental functions achievement conflict. This proposal depends on determining the inconsistency assessment items that depend on common building components to be achieved, and then determining the time periods that these items are achieved together within, to indicate the time periods without conflicting. Thus, the paper aims to raise the building environmental value in the assessment when the designer succeeds to minimize the expected conflict of the building environmental functions.展开更多
文摘A bimorph piezoelectric beam with periodically variable cross-sections is used for the vibration energy harvesting. The effects of two geometrical parameters on the first band gap of this periodic beam are investigated by the generalized differential quadrature rule （GDQR） method. The GDQR method is also used to calculate the forced vibration response of the beam and voltage of each piezoelectric layer when the beam is subject to a sinusoidal base excitation. Results obtained from the analytical method are compared with those obtained from the finite element simulation with ANSYS, and good agreement is found. The voltage output of this periodic beam over its first band gap is calculated and compared with the voltage output of the uniform piezoelectric beam. It is concluded that this periodic beam has three advantages over the uniform piezoelectric beam, i.e., generating more voltage outputs over a wide frequency range, absorbing vibration, and being less weight.
文摘In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the spaces of Lipschitz continuous functions. It has also been proved that the space of fractional integration,the space of Lipschitz continuous functions and the Sobolev space are identical in L^2-norm.Results obtainedhere are not true for fractional integrals(or Riesz potentials)in R^n.
文摘Some building components are responsible for achieving more than one environmental function, these functions are usually of different requirements that can never be done by the same actions, and they are usually connected to changeable internal and external environment characteristics that vary among them. Minimizing the conflict of achieving the different environmental functions is an important challenge for all designers. Achieving a continuous thermal and optical comfort in an internal building space using the same window is an example of this challenge, as they have different requirements that may be sometimes contrary. It should be notable that there are a lot of recent technologies that may be used to find solutions for such a conflict. The Environmental Assessment Methods of Buildings appeared to set the principles of the optimum relation between buildings and their environment, they also could be used to encourage designers to reach the best environmental relations, and award them by main or additional assessment points. The research paper proposes to use the Environmental Assessment Methods of Buildings to assess the building ability of minimizing its environmental functions achievement conflict. This proposal depends on determining the inconsistency assessment items that depend on common building components to be achieved, and then determining the time periods that these items are achieved together within, to indicate the time periods without conflicting. Thus, the paper aims to raise the building environmental value in the assessment when the designer succeeds to minimize the expected conflict of the building environmental functions.
