Using disordered multinomial logistic regression and multiple linear regression method,385 copies of questionnaires on farmer are analyzed to explore the relationship between peasant's psychological traits,peasant...Using disordered multinomial logistic regression and multiple linear regression method,385 copies of questionnaires on farmer are analyzed to explore the relationship between peasant's psychological traits,peasant's cognition on seed technology and perception on supplydemand matching of new variety.Research results show that the vast majority of farmers think that current new variety is at high-level supplydemand balance and the oversupply status,and updating speed of new variety on the market is faster;the farmers preferring risk,seeking innovation and having strong learning and cognition ability may select high-level supply-demand matching state,and the farmers understanding the importance and difference of seed technology tend to choose high-level supply-demand matching situation;the farmers with strong learning and cognition ability can acknowledge the importance and difference of seed technology,while the farmers preferring risk can perceive the difference of seed technology;psychology seeking the innovation and learning and cognition ability affect the farmer's perception on supplydemand matching status of new variety via affecting the farmer's cognition on technical difference.展开更多
The paper explores the optimal price strategy under the price-matching policy. First, the paper formulates the demand function under the price match policy and then discovers the retailer’s best response facing the p...The paper explores the optimal price strategy under the price-matching policy. First, the paper formulates the demand function under the price match policy and then discovers the retailer’s best response facing the price-matching pressure. From the theoretical analysis, we discover how the number of retailers plays an important role during the competition. When only two retailers are involved, the final prices may not converge to a single value. However, when more retailers are involved, the final price will converge to a single value. We also use numerical studies to illuminate the change of the prices over the time period, the sensitivity of the final price to the increment/decrement of initial prices. Finally, we provide managerial suggestions to both producers and retailers.展开更多
访问控制是应用系统中的重要问题之一。传统的基于角色的访问控制(RBAC)方案需要预先定义和同步用户-角色赋值关系,这会带来管理成本和同步开销,并且限制了应用系统的灵活性和动态性。文章提出一种基于策略的动态角色分配模型(Policy-ba...访问控制是应用系统中的重要问题之一。传统的基于角色的访问控制(RBAC)方案需要预先定义和同步用户-角色赋值关系,这会带来管理成本和同步开销,并且限制了应用系统的灵活性和动态性。文章提出一种基于策略的动态角色分配模型(Policy-based Dynamic Role Assignment Model——PDRA),它无需同步用户就可以自定义角色,并通过策略匹配的方式实现动态分配。模型完全兼容RBAC,可以成为RBAC良好的扩展机制。文章给出了模型的定义和算法,评估了模型的性能,并在华东师范大学的数据治理平台中进行了应用,验证了该方案的可行性和有效性。展开更多
文摘Using disordered multinomial logistic regression and multiple linear regression method,385 copies of questionnaires on farmer are analyzed to explore the relationship between peasant's psychological traits,peasant's cognition on seed technology and perception on supplydemand matching of new variety.Research results show that the vast majority of farmers think that current new variety is at high-level supplydemand balance and the oversupply status,and updating speed of new variety on the market is faster;the farmers preferring risk,seeking innovation and having strong learning and cognition ability may select high-level supply-demand matching state,and the farmers understanding the importance and difference of seed technology tend to choose high-level supply-demand matching situation;the farmers with strong learning and cognition ability can acknowledge the importance and difference of seed technology,while the farmers preferring risk can perceive the difference of seed technology;psychology seeking the innovation and learning and cognition ability affect the farmer's perception on supplydemand matching status of new variety via affecting the farmer's cognition on technical difference.
文摘The paper explores the optimal price strategy under the price-matching policy. First, the paper formulates the demand function under the price match policy and then discovers the retailer’s best response facing the price-matching pressure. From the theoretical analysis, we discover how the number of retailers plays an important role during the competition. When only two retailers are involved, the final prices may not converge to a single value. However, when more retailers are involved, the final price will converge to a single value. We also use numerical studies to illuminate the change of the prices over the time period, the sensitivity of the final price to the increment/decrement of initial prices. Finally, we provide managerial suggestions to both producers and retailers.
文摘访问控制是应用系统中的重要问题之一。传统的基于角色的访问控制(RBAC)方案需要预先定义和同步用户-角色赋值关系,这会带来管理成本和同步开销,并且限制了应用系统的灵活性和动态性。文章提出一种基于策略的动态角色分配模型(Policy-based Dynamic Role Assignment Model——PDRA),它无需同步用户就可以自定义角色,并通过策略匹配的方式实现动态分配。模型完全兼容RBAC,可以成为RBAC良好的扩展机制。文章给出了模型的定义和算法,评估了模型的性能,并在华东师范大学的数据治理平台中进行了应用,验证了该方案的可行性和有效性。