Mathematics homework is an important part of mathematics teaching. The new curriculum reform has not made specific measures for mathematics homework. At present, teachers dont know how to design layered homework in ho...Mathematics homework is an important part of mathematics teaching. The new curriculum reform has not made specific measures for mathematics homework. At present, teachers dont know how to design layered homework in homework arrangement. Mathematics is a logical subject, and most students have resistance to mathematics learning. Some researchers use the experimental method to study the design of elementary school mathematics stratified homework, taking the students in parallel classes as the research objects, and designing the mathematics homework to meet the students learning needs according to the students learning characteristics. Based on this, this paper studies the optimal design strategy of hierarchical exercises of senior mathematics in primary schools for reference.展开更多
Traditional modular design methods lead to product maintenance problems, because the module form of a system is created according to either the function requirements or the manufacturing considerations. For solving th...Traditional modular design methods lead to product maintenance problems, because the module form of a system is created according to either the function requirements or the manufacturing considerations. For solving these problems, a new modular design method is proposed with the considerations of not only the traditional function related attributes, but also the maintenance related ones. First, modularity parameters and modularity scenarios for product modularity are defined. Then the reliability and economic assessment models of product modularity strategies are formulated with the introduction of the effective working age of modules. A mathematical model used to evaluate the difference among the modules of the product so that the optimal module of the product can be established. After that, a multi-objective optimization problem based on metrics for preventive maintenance interval different degrees and preventive maintenance economics is formulated for modular optimization. Multi-objective GA is utilized to rapidly approximate the Pareto set of optimal modularity strategy trade-offs between preventive maintenance cost and preventive maintenance interval difference degree. Finally, a coordinate CNC boring machine is adopted to depict the process of product modularity. In addition, two factorial design experiments based on the modularity parameters are constructed and analyzed. These experiments investigate the impacts of these parameters on the optimal modularity strategies and the structure of module. The research proposes a new modular design method, which may help to improve the maintainability of product in modular design.展开更多
The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers b...The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers both bus network design and public bicycle network design is proposed. The chemical reaction optimization(CRO) is designed to solve the problem. A shortcoming of CRO is that, when the two-molecule collisions take place, the molecules are randomly picked from the container.Hence, we improve CRO by employing different mating strategies. The computational results confirm the benefits of the mating strategies. Numerical experiments are conducted on the Sioux-Falls network. A comparison with the traditional sequential modeling framework indicates that the proposed approach has a better performance and is more robust. The practical applicability of the approach is proved by employing a real size network.展开更多
文摘Mathematics homework is an important part of mathematics teaching. The new curriculum reform has not made specific measures for mathematics homework. At present, teachers dont know how to design layered homework in homework arrangement. Mathematics is a logical subject, and most students have resistance to mathematics learning. Some researchers use the experimental method to study the design of elementary school mathematics stratified homework, taking the students in parallel classes as the research objects, and designing the mathematics homework to meet the students learning needs according to the students learning characteristics. Based on this, this paper studies the optimal design strategy of hierarchical exercises of senior mathematics in primary schools for reference.
基金Supported by National Natural Science Foundation of China(Grant Nos.51205347,51322506)Zhejiang Provincial Natural Science Foundation of China(Grant No.LR14E050003)+3 种基金Project of National Science and Technology Plan of China(Grant No.2013IM030500)Fundamental Research Funds for the Central Universities of ChinaInnovation Foundation of the State Key Laboratory of Fluid Power Transmission and Control of ChinaZhejiang University K.P.Chao’s High Technology Development Foundation of China
文摘Traditional modular design methods lead to product maintenance problems, because the module form of a system is created according to either the function requirements or the manufacturing considerations. For solving these problems, a new modular design method is proposed with the considerations of not only the traditional function related attributes, but also the maintenance related ones. First, modularity parameters and modularity scenarios for product modularity are defined. Then the reliability and economic assessment models of product modularity strategies are formulated with the introduction of the effective working age of modules. A mathematical model used to evaluate the difference among the modules of the product so that the optimal module of the product can be established. After that, a multi-objective optimization problem based on metrics for preventive maintenance interval different degrees and preventive maintenance economics is formulated for modular optimization. Multi-objective GA is utilized to rapidly approximate the Pareto set of optimal modularity strategy trade-offs between preventive maintenance cost and preventive maintenance interval difference degree. Finally, a coordinate CNC boring machine is adopted to depict the process of product modularity. In addition, two factorial design experiments based on the modularity parameters are constructed and analyzed. These experiments investigate the impacts of these parameters on the optimal modularity strategies and the structure of module. The research proposes a new modular design method, which may help to improve the maintainability of product in modular design.
基金Projects(71301115,71271150,71101102)supported by the National Natural Science Foundation of ChinaProject(20130032120009)supported by Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers both bus network design and public bicycle network design is proposed. The chemical reaction optimization(CRO) is designed to solve the problem. A shortcoming of CRO is that, when the two-molecule collisions take place, the molecules are randomly picked from the container.Hence, we improve CRO by employing different mating strategies. The computational results confirm the benefits of the mating strategies. Numerical experiments are conducted on the Sioux-Falls network. A comparison with the traditional sequential modeling framework indicates that the proposed approach has a better performance and is more robust. The practical applicability of the approach is proved by employing a real size network.
