This research is focused on the singularity analysis for single-gimbal control moment gyros systems （SCMGs） which include two types, with constant speed （CSCMG） or variable speed （VSCMG） rotors. Through angular ...This research is focused on the singularity analysis for single-gimbal control moment gyros systems （SCMGs） which include two types, with constant speed （CSCMG） or variable speed （VSCMG） rotors. Through angular momentum hypersurfaces of singular states, the passable and impassable singular points are discriminated easily, meanwhile the information about how much the angular momentum workspace as well as the steering capability available is provided directly. It is obvious that the null motions of steering laws are more effective for the five pyramid configuration（FPC） than for the pyramid configuration（PC） from the singular plots. The possible degenerate hyperbolic singular points of the preceding configurations are calculated and the distinctness of them is denoted by the Gaussian curvature. Furthermore, failure problems to steer integrated power and attitude control system （IPACS） are also analyzed. A sufficient condition of choosing configurations of VSCMGs to guarantee the IPACS steering is given. The angular momentum envelops of VSCMGs, in a given energy and a limited range of rotor speeds, are plotted. The connection and distinctness between CSCMGs and VSCMGs are obtained from the point of view of envelops.展开更多
Retail stores are responsible for large energy consumption, which requires more intensified action to improve energy efficiency. Effective energy management can improve energy efficiency in retail stores. However, it...Retail stores are responsible for large energy consumption, which requires more intensified action to improve energy efficiency. Effective energy management can improve energy efficiency in retail stores. However, it is a challenge to implement energy management in retail stores due to different stakeholders’ roles and diverse store features. Literally, technical and management aspects of energy management have received much attention in research. However, limited studies systemically investigate internal and external factors and stakeholders’ involvement in the energy management of retail buildings. With multi-cases in the Philippines, this paper examines the energy profiles in retail stores and develops an assessment for energy management in retail stores. The assessment includes store features, internal and external stakeholders, climate, electricity price and grid condition, energy consumption, and management. The assessment can assist retail stores to develop their energy management plans with their store profile.展开更多
Today’s world is stressed by the ever-increasing demand for energy and the disastrous climate changes.New technologies that generate,convert,and store energy in a greener and more efficient way become increasingly cr...Today’s world is stressed by the ever-increasing demand for energy and the disastrous climate changes.New technologies that generate,convert,and store energy in a greener and more efficient way become increasingly critical in building a sustainable society.On this front,batteries,capacitors,fuel cells,and solar cells play the indispensable roles as the powers for applications,for example,electric vehicles shall mitigate our reliance on the depleting fossil fuels.It is crucial to invent new materials or technologies to improve the electrochemical performance of energy storage/conversion devices with higher energy,better power,longer cycle life,and better safety.One of the most important areas pertains to carbon-based materials.Researchers from different fields design carbon-based materials for low-cost energy devices with great portability and functionality.展开更多
文摘This research is focused on the singularity analysis for single-gimbal control moment gyros systems （SCMGs） which include two types, with constant speed （CSCMG） or variable speed （VSCMG） rotors. Through angular momentum hypersurfaces of singular states, the passable and impassable singular points are discriminated easily, meanwhile the information about how much the angular momentum workspace as well as the steering capability available is provided directly. It is obvious that the null motions of steering laws are more effective for the five pyramid configuration（FPC） than for the pyramid configuration（PC） from the singular plots. The possible degenerate hyperbolic singular points of the preceding configurations are calculated and the distinctness of them is denoted by the Gaussian curvature. Furthermore, failure problems to steer integrated power and attitude control system （IPACS） are also analyzed. A sufficient condition of choosing configurations of VSCMGs to guarantee the IPACS steering is given. The angular momentum envelops of VSCMGs, in a given energy and a limited range of rotor speeds, are plotted. The connection and distinctness between CSCMGs and VSCMGs are obtained from the point of view of envelops.
文摘Retail stores are responsible for large energy consumption, which requires more intensified action to improve energy efficiency. Effective energy management can improve energy efficiency in retail stores. However, it is a challenge to implement energy management in retail stores due to different stakeholders’ roles and diverse store features. Literally, technical and management aspects of energy management have received much attention in research. However, limited studies systemically investigate internal and external factors and stakeholders’ involvement in the energy management of retail buildings. With multi-cases in the Philippines, this paper examines the energy profiles in retail stores and develops an assessment for energy management in retail stores. The assessment includes store features, internal and external stakeholders, climate, electricity price and grid condition, energy consumption, and management. The assessment can assist retail stores to develop their energy management plans with their store profile.
文摘Today’s world is stressed by the ever-increasing demand for energy and the disastrous climate changes.New technologies that generate,convert,and store energy in a greener and more efficient way become increasingly critical in building a sustainable society.On this front,batteries,capacitors,fuel cells,and solar cells play the indispensable roles as the powers for applications,for example,electric vehicles shall mitigate our reliance on the depleting fossil fuels.It is crucial to invent new materials or technologies to improve the electrochemical performance of energy storage/conversion devices with higher energy,better power,longer cycle life,and better safety.One of the most important areas pertains to carbon-based materials.Researchers from different fields design carbon-based materials for low-cost energy devices with great portability and functionality.
