With the advantage of fast charge transfer,heterojunction engineering is identified as a viable method to reinforce the anodes'sodium storage performance.Also,vacancies can effectively strengthen the Na+adsorption...With the advantage of fast charge transfer,heterojunction engineering is identified as a viable method to reinforce the anodes'sodium storage performance.Also,vacancies can effectively strengthen the Na+adsorption ability and provide extra active sites for Na+adsorption.However,their synchronous engineering is rarely reported.Herein,a hybrid of Co_(0.85)Se/WSe_(2) heterostructure with Se vacancies and N-doped carbon polyhedron(CoWSe/NCP)has been fabricated for the first time via a hydrothermal and subsequent selenization strategy.Spherical aberration-corrected transmission electron microscopy confirms the phase interface of the Co_(0.85)Se/WSe_(2) heterostructure and the existence of Se vacancies.Density functional theory simulations reveal the accelerated charge transfer and enhanced Na+adsorption ability,which are contributed by the Co_(0.85)Se/WSe_(2) heterostructure and Se vacancies,respectively.As expected,the CoWSe/NCP anode in sodium-ion battery achieves outstanding rate capability(339.6 mAh g^(−1) at 20 A g^(−1)),outperforming almost all Co/W-based selenides.展开更多
Regularized Boolean operations have been widely used in 3D modeling systems. However, evaluating Boolean operations may be quite numerically unstable and time consuming, especially for iterated set operations. A novel...Regularized Boolean operations have been widely used in 3D modeling systems. However, evaluating Boolean operations may be quite numerically unstable and time consuming, especially for iterated set operations. A novel and unified technique is proposed in this paper for computing single and iterated set operations efficiently, robustly and exactly. An adaptive octree is combined with a nested constructive solid geometry (CSG) tree by this technique. The intersection handling is restricted to the cells in the octree where intersection actually occurs. Within those cells, a CSG tree template is instanced by the surfaces and the tree is converted to planebased binary space partitioning (BSP) for set evaluation; Moreover, the surface classification is restricted to the ceils in the octree where the surfaces only come from a model and are within the bounding-boxes of other polyhedrons. These two ways bring about the efficiency and scalability of the operations, in terms of runtime and memory. As all surfaces in such a cell have the same classification relation, they are classified as a whole. Robustness and exactness are achieved by integrating plane-based geometry representation with adaptive geometry predicate technique in intersection handling, and by applying divide-and-conquer arithmetic on surface classification. Experimental results demonstrate that the proposed approach can guarantee the robustness of Boolean computations and runs faster than other existing approaches.展开更多
针对求解多目标优化问题(MOP:Multi-Objective Problem)时,人工蜂群算法(ABC:Artificial Bee Colony)存在难以收敛和候选解多样性难以保持的问题,对其各部分求解策略进行了改进。基于ABC算法框架,设计了一种基于自适应求解策略的多目标...针对求解多目标优化问题(MOP:Multi-Objective Problem)时,人工蜂群算法(ABC:Artificial Bee Colony)存在难以收敛和候选解多样性难以保持的问题,对其各部分求解策略进行了改进。基于ABC算法框架,设计了一种基于自适应求解策略的多目标ABC算法,并在机电执行器设计的实际应用工程设计问题中,将所提出的改进多目标ABC与其他典型的群智能算法进行优化性能比较。通过实验验证可知,所提出的MOABC/DD(Multi-Objective Artificial Bee Colony Based on Dominance and Decomposition)算法在求解机电执行器设计问题基准测试用例时,与典型算法相比,具有较好的问题求解精度。并且MOABC/DD的实验结果较为稳定,从而证明了MOABC/DD具有较高的求解稳定性和健壮性。展开更多
调整优化城市土地利用结构与布局,实现社会经济发展和生态保护的协同优化是城市土地利用规划管理和决策的关键。该研究使用多目标规划(multiple objective planning,MOP)模型和未来土地利用模拟(future land use simulation model,FLUS...调整优化城市土地利用结构与布局,实现社会经济发展和生态保护的协同优化是城市土地利用规划管理和决策的关键。该研究使用多目标规划(multiple objective planning,MOP)模型和未来土地利用模拟(future land use simulation model,FLUS)模型相结合的方法,运用权衡分析制定多目标权衡下的土地利用优化配置情景方案,以期为杭州市土地利用优化配置规划和管理提供科学参考。结果表明:1)通过耦合MOP模型和FLUS模型,从土地利用生态-经济转化效率视角可以有效实现土地利用结构和布局的优化配置情景模拟。2)通过比较单位经济效益的减少比例可产生的生态效益增加比例,确定土地利用经济与生态效益权重比例为4:6的发展情景是权衡土地利用社会、经济和生态效益下的杭州市土地利用结构最优方案。3)最优土地利用结构方案的建设用地扩张规模介于经济发展优化和生态保护优先情景方案间,耕地规模较其他情景方案减少幅度放缓,在空间上减少对生态用地的侵占,土地利用景观格局破碎度和复杂性降低。该研究的方法和结果可为区域土地利用规划决策和可持续发展提供理论与应用参考。展开更多
基金support from the Natural Science Foundation of Jilin Province(Grant No.20200201073JC)the National Natural Science Foundation of China(Grant No.52130101)+1 种基金Interdisciplinary Integration and Innovation Project of JLU(Grant No.JLUXKJC2021ZY01)the Fundamental Research Funds for the Central Universities.
文摘With the advantage of fast charge transfer,heterojunction engineering is identified as a viable method to reinforce the anodes'sodium storage performance.Also,vacancies can effectively strengthen the Na+adsorption ability and provide extra active sites for Na+adsorption.However,their synchronous engineering is rarely reported.Herein,a hybrid of Co_(0.85)Se/WSe_(2) heterostructure with Se vacancies and N-doped carbon polyhedron(CoWSe/NCP)has been fabricated for the first time via a hydrothermal and subsequent selenization strategy.Spherical aberration-corrected transmission electron microscopy confirms the phase interface of the Co_(0.85)Se/WSe_(2) heterostructure and the existence of Se vacancies.Density functional theory simulations reveal the accelerated charge transfer and enhanced Na+adsorption ability,which are contributed by the Co_(0.85)Se/WSe_(2) heterostructure and Se vacancies,respectively.As expected,the CoWSe/NCP anode in sodium-ion battery achieves outstanding rate capability(339.6 mAh g^(−1) at 20 A g^(−1)),outperforming almost all Co/W-based selenides.
基金supported by the Natural Science Foundation of China under Grant No.61202154 and No.61133009the National Basic Research Project of China under Grant No.2011CB302203+2 种基金Shanghai Pujiang Program under Grant No.13PJ1404500the Science and Technology Commission of Shanghai Municipality Program under Grant No.13511505000the Open Project Program of the State Key Lab of CAD&CG of Zhejiang University under Grant No.A1401
文摘Regularized Boolean operations have been widely used in 3D modeling systems. However, evaluating Boolean operations may be quite numerically unstable and time consuming, especially for iterated set operations. A novel and unified technique is proposed in this paper for computing single and iterated set operations efficiently, robustly and exactly. An adaptive octree is combined with a nested constructive solid geometry (CSG) tree by this technique. The intersection handling is restricted to the cells in the octree where intersection actually occurs. Within those cells, a CSG tree template is instanced by the surfaces and the tree is converted to planebased binary space partitioning (BSP) for set evaluation; Moreover, the surface classification is restricted to the ceils in the octree where the surfaces only come from a model and are within the bounding-boxes of other polyhedrons. These two ways bring about the efficiency and scalability of the operations, in terms of runtime and memory. As all surfaces in such a cell have the same classification relation, they are classified as a whole. Robustness and exactness are achieved by integrating plane-based geometry representation with adaptive geometry predicate technique in intersection handling, and by applying divide-and-conquer arithmetic on surface classification. Experimental results demonstrate that the proposed approach can guarantee the robustness of Boolean computations and runs faster than other existing approaches.
文摘针对求解多目标优化问题(MOP:Multi-Objective Problem)时,人工蜂群算法(ABC:Artificial Bee Colony)存在难以收敛和候选解多样性难以保持的问题,对其各部分求解策略进行了改进。基于ABC算法框架,设计了一种基于自适应求解策略的多目标ABC算法,并在机电执行器设计的实际应用工程设计问题中,将所提出的改进多目标ABC与其他典型的群智能算法进行优化性能比较。通过实验验证可知,所提出的MOABC/DD(Multi-Objective Artificial Bee Colony Based on Dominance and Decomposition)算法在求解机电执行器设计问题基准测试用例时,与典型算法相比,具有较好的问题求解精度。并且MOABC/DD的实验结果较为稳定,从而证明了MOABC/DD具有较高的求解稳定性和健壮性。
文摘调整优化城市土地利用结构与布局,实现社会经济发展和生态保护的协同优化是城市土地利用规划管理和决策的关键。该研究使用多目标规划(multiple objective planning,MOP)模型和未来土地利用模拟(future land use simulation model,FLUS)模型相结合的方法,运用权衡分析制定多目标权衡下的土地利用优化配置情景方案,以期为杭州市土地利用优化配置规划和管理提供科学参考。结果表明:1)通过耦合MOP模型和FLUS模型,从土地利用生态-经济转化效率视角可以有效实现土地利用结构和布局的优化配置情景模拟。2)通过比较单位经济效益的减少比例可产生的生态效益增加比例,确定土地利用经济与生态效益权重比例为4:6的发展情景是权衡土地利用社会、经济和生态效益下的杭州市土地利用结构最优方案。3)最优土地利用结构方案的建设用地扩张规模介于经济发展优化和生态保护优先情景方案间,耕地规模较其他情景方案减少幅度放缓,在空间上减少对生态用地的侵占,土地利用景观格局破碎度和复杂性降低。该研究的方法和结果可为区域土地利用规划决策和可持续发展提供理论与应用参考。