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1.
“请”字用法汉英对比的语用分析   总被引:1,自引:0,他引:1  
迁移是语际语用学和二语习得研究领域的重要范畴。现回顾迁移的相关理论,并考察请字在汉英两种语言里的用法及其异同点。并指出母语与知识对目的语表达的牵制作用、对母语句式或用法的泛化以及语言表达背后的社会价值观是造成语用负迁移的重要原因。  相似文献   
2.
建立科学有效的国有企业经营者激励与约束机制是国企改革的客观要求。当前国企经营者激励与约束机制在运行中存在诸多问题。必须尽快建立和完善现代企业制度 ;实行规范的年薪制 ;针对不同类型的国有企业分类指导 ;强化市场机制的基础性调节作用  相似文献   
3.
提出了变质量系统的相对论性万有D’Alembert原理,构造了相对论性广义动能函数,建立了变质量任意阶非线性非完整系统在准坐标下和广义坐标下的相对论性广义Mar-Millan型方程,并得到厂相应的型方程  相似文献   
4.
In this paper, we consider the application of the empirical likelihood for

linear models under median constraints in view of robustness. For two simple median constraints, it is shown that conditions to ensure the consistency of the empirical likelihood confidence regions can be surprisingly relaxed compared with the normal approach under L norm. However, the coverage accuracy of the empirical likelihood confidence regions based on simple median constrains cannot be improved because of the discontinuity of the constraints. Therefore, a smoothed version of median constraint is proposed and a general theory is established to ensure its validity.  相似文献   
5.
This paper provides a Bayesian estimation procedure for monotone regression models incorporating the monotone trend constraint subject to uncertainty. For monotone regression modeling with stochastic restrictions, we propose a Bayesian Bernstein polynomial regression model using two-stage hierarchical prior distributions based on a family of rectangle-screened multivariate Gaussian distributions extended from the work of Gurtis and Ghosh [7 S.M. Curtis and S.K. Ghosh, A variable selection approach to monotonic regression with Bernstein polynomials, J. Appl. Stat. 38 (2011), pp. 961976. doi: 10.1080/02664761003692423[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]]. This approach reflects the uncertainty about the prior constraint, and thus proposes a regression model subject to monotone restriction with uncertainty. Based on the proposed model, we derive the posterior distributions for unknown parameters and present numerical schemes to generate posterior samples. We show the empirical performance of the proposed model based on synthetic data and real data applications and compare the performance to the Bernstein polynomial regression model of Curtis and Ghosh [7 S.M. Curtis and S.K. Ghosh, A variable selection approach to monotonic regression with Bernstein polynomials, J. Appl. Stat. 38 (2011), pp. 961976. doi: 10.1080/02664761003692423[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]] for the shape restriction with certainty. We illustrate the effectiveness of our proposed method that incorporates the uncertainty of the monotone trend and automatically adapts the regression function to the monotonicity, through empirical analysis with synthetic data and real data applications.  相似文献   
6.
为提高车辆的可装载性,对考虑三维装载约束带时间窗的循环取货路径问题进行研究.在给定假设与约束条件的前提下,建立该问题的多目标数学模型,并设计用于问题求解的基于改进策略的启发式算法.数值实例的计算结果表明,该算法可有效求解考虑零件三维装载约束带时间窗的循环取货路径问题;且与时间窗优先法的求解结果相比,可大幅提高车辆的可装载性,并能有效减少不同车型车辆的投入数量.  相似文献   
7.
流动性约束与消费行为关系的实证研究   总被引:2,自引:1,他引:2  
流动性约束是指资本市场的资金流动具有单向性,流动性约束的存在可以提高储蓄水 平,降低当期累积消费. 通过三阶段生命期界的最优消费模型,证明了流动性约束的定量存在, 并通过实证检验发现,我国消费总量中受流动性约束影响的比例达到83. 46 %. 因此,增强信 贷市场的流动性,对于扩张有效需求将起重要作用.  相似文献   
8.
In contrast to the classical newsboy-style problem, this paper develops a model for the multiple-item budget-constraint newsboy problem considering a reservation policy to meet marketing needs. A discount rate is provided to those customers who are willing to make a reservation. In addition to the demand from the original customers, extra demand is also included in the model due to the motivation of the discount rate. A solution algorithm, namely the MCR algorithm, is proposed to solve the problem. The proposed algorithm can actually be considered as a generalization of the classical newsboy-style problem. The MCR algorithm not only provides a business unit with the optimal order quantity, but also the discount rate necessary to achieve the maximal total expected profit under a limited budget. From the illustrated example, it is shown that the expected profit from the proposed model is greater than that from the classical model, due to the consideration of reservations, even though the budget constraint is tight. The increase in the expected profit could be treated as an information value from the willingness function. Although the proposed model is developed for multiple-item problems, it also can be applied to single-item ones. From the sensitivity analysis, the application of the single-item problem to the proposed model can still obtain greater expected profit than the classical model under different budgetary levels.  相似文献   
9.
Upper Bounds for the SPOT 5 Daily Photograph Scheduling Problem   总被引:10,自引:0,他引:10  
This paper introduces tight upper bounds for the daily photograph scheduling problem of earth observation satellites. These bounds, which were unavailable until now, allow us to assess the quality of the heuristic solutions obtained previously. These bounds are obtained with a partition-based approach following the divide and pas conquer principle. Dynamic programming and tabu search are conjointly used in this approach. We present also simplex-based linear programming relaxation and a relaxed knapsack approach for the problem.  相似文献   
10.
针对QFD 系统的内在模糊性,运用带有对称三角形模糊系数的模糊规划理论,提出了一 种确定QFD 系统参数的方法. 并通过工程特性目标值的规范化,定义产品开发总成本函数、工 程特性改进成本函数及改进成本系数等概念,建立了一个QFD 规划模型. 仿真结果表明,该模 型能够帮助开发人员在不确定的、模糊条件下有效确定关联函数及自相关函数,优化顾客需求 的满意水平,确定工程特性目标值,使新开发/ 改进的产品顾客满意度赶上或超过目标市场上 的竞争企业,并满足开发预算约束.  相似文献   
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