Increased penetration of electric vehicles(EVs)is expected to impact power system performance in adverse ways,e.g.,overloading,uncertain power quality,and increased voltage fluctuation,particularly at the distribution...Increased penetration of electric vehicles(EVs)is expected to impact power system performance in adverse ways,e.g.,overloading,uncertain power quality,and increased voltage fluctuation,particularly at the distribution level.Most EV charging control strategies that have been proposed only benefit the grid or EV users.A centralized EV charging strategy based on bilevel optimization is proposed in this paper with the objectives of deriving benefits for the grid and EV users simultaneously.The proposed strategy involves distributing the EV charging load more beneficially across both spatial and temporal levels.In the spatial problem,the whole fleet of EVs is controlled to minimize load variance as spatial coordination,with total charging rate and energy needed as the constraint.While in the temporal problem,EVs in each aggregator are controlled to minimize the charging cost or maximize the EV user’s degree of satisfaction with each aggregator’s charging rate and energy needed as the constraint.The proposed bi-level charging strategy is transformed to a single-stage optimization problem and solved using the classical optimization method.The impacts of uncontrolled charging on the grid and EV users are studied using the Monte Carlo Simulation(MCS)method.Then,the effectiveness of the proposed charging strategy is demonstrated via results obtained in the MCS.展开更多
A method for precise conversion between virtual world and real world is put forward in this paper. The method aims to precisely establish the connection between the virtual coordinates and the real coordinates with Op...A method for precise conversion between virtual world and real world is put forward in this paper. The method aims to precisely establish the connection between the virtual coordinates and the real coordinates with OpenGL. In the virtual world, two virtual cameras are set to capture the left and right perspective planar images, and coordinates of the planar images can be calculated by the perspective projection model. With coordinates of planar images, coordinates of the stereo- scopic image synthesized in the real world can be calculated by the binocular observation model. Therefore, the corresponding connection between the two systems is established. Experimental re- suits match data from this method well. Therefore, this method can precisely realize the conversion and the interactivity, laying a solid foundation for further study.展开更多
Presents the detailed algorithm established for determination of workspace for a 3-DOF coordinate measuring machine using parallel link mechanism by constructing the inverse kinematic model first and then reviewing th...Presents the detailed algorithm established for determination of workspace for a 3-DOF coordinate measuring machine using parallel link mechanism by constructing the inverse kinematic model first and then reviewing the physical and kinematical constraints from the structural characteristics of the parallel link mechanism, and discusses the actual geometries of workspace and the factors having effect on workspace through computer simulation thereby providing necessary theoretical basis for the research and development of coordinate measuring machines using parallel link mechanism.展开更多
A continuum thermodynamic model for how whirls can transform into thermal energy-forms determined by a functional relation for temperature is derived. This is used to describe how fishes maintain circulation in the va...A continuum thermodynamic model for how whirls can transform into thermal energy-forms determined by a functional relation for temperature is derived. This is used to describe how fishes maintain circulation in the vascular system, at very low temperatures.展开更多
The diverse morphologies among vertebrate species stems from the evolution of a basic body plan that is constituted by a spatially organized ensemble of tissue lineage progenitors. At gastrulation, this body plan is e...The diverse morphologies among vertebrate species stems from the evolution of a basic body plan that is constituted by a spatially organized ensemble of tissue lineage progenitors. At gastrulation, this body plan is established through a coordinated morphogenetic process and the delineation of tissue lineages that are driven by the activity of the genome. To explore the molecular mechanisms, in a comprehensive context, it is imperative to glean an understanding of the region-and population-specific genetic activity underpinning this fundamental developmental process. In this review, we outline the recent progress and the future directions in studies of genome activity for the regulation of mouse embryogenesis at gastrulation.展开更多
基金This work was supported by the Fundamental Research Funds for the Central Universities(No.2014XS09).
文摘Increased penetration of electric vehicles(EVs)is expected to impact power system performance in adverse ways,e.g.,overloading,uncertain power quality,and increased voltage fluctuation,particularly at the distribution level.Most EV charging control strategies that have been proposed only benefit the grid or EV users.A centralized EV charging strategy based on bilevel optimization is proposed in this paper with the objectives of deriving benefits for the grid and EV users simultaneously.The proposed strategy involves distributing the EV charging load more beneficially across both spatial and temporal levels.In the spatial problem,the whole fleet of EVs is controlled to minimize load variance as spatial coordination,with total charging rate and energy needed as the constraint.While in the temporal problem,EVs in each aggregator are controlled to minimize the charging cost or maximize the EV user’s degree of satisfaction with each aggregator’s charging rate and energy needed as the constraint.The proposed bi-level charging strategy is transformed to a single-stage optimization problem and solved using the classical optimization method.The impacts of uncontrolled charging on the grid and EV users are studied using the Monte Carlo Simulation(MCS)method.Then,the effectiveness of the proposed charging strategy is demonstrated via results obtained in the MCS.
基金Supported by the National Natural Science Foundation of China ( 60674052)
文摘A method for precise conversion between virtual world and real world is put forward in this paper. The method aims to precisely establish the connection between the virtual coordinates and the real coordinates with OpenGL. In the virtual world, two virtual cameras are set to capture the left and right perspective planar images, and coordinates of the planar images can be calculated by the perspective projection model. With coordinates of planar images, coordinates of the stereo- scopic image synthesized in the real world can be calculated by the binocular observation model. Therefore, the corresponding connection between the two systems is established. Experimental re- suits match data from this method well. Therefore, this method can precisely realize the conversion and the interactivity, laying a solid foundation for further study.
文摘Presents the detailed algorithm established for determination of workspace for a 3-DOF coordinate measuring machine using parallel link mechanism by constructing the inverse kinematic model first and then reviewing the physical and kinematical constraints from the structural characteristics of the parallel link mechanism, and discusses the actual geometries of workspace and the factors having effect on workspace through computer simulation thereby providing necessary theoretical basis for the research and development of coordinate measuring machines using parallel link mechanism.
文摘A continuum thermodynamic model for how whirls can transform into thermal energy-forms determined by a functional relation for temperature is derived. This is used to describe how fishes maintain circulation in the vascular system, at very low temperatures.
基金supported by the “Strategic Priority Research Program” of the Chinese Academy of Sciences (XDA01010201)National Key Basic Research and Development Program of China (2014CB964804, 2015CB964500)National Natural Science Foundation of China (31430058, 31571513, 31630043, 91519314)
文摘The diverse morphologies among vertebrate species stems from the evolution of a basic body plan that is constituted by a spatially organized ensemble of tissue lineage progenitors. At gastrulation, this body plan is established through a coordinated morphogenetic process and the delineation of tissue lineages that are driven by the activity of the genome. To explore the molecular mechanisms, in a comprehensive context, it is imperative to glean an understanding of the region-and population-specific genetic activity underpinning this fundamental developmental process. In this review, we outline the recent progress and the future directions in studies of genome activity for the regulation of mouse embryogenesis at gastrulation.
