精确农业在我国的推广应用分析

介绍了精确农业的概念及其技术系统;分析了我国发展精确农业的必要性和可行性;针对我国农业现状,提出在我国不同区域,发展不同阶段的精确农业的构想。     

资源型城市转型的战略构想

资源型城市经济转型,是一个全球性的难题,是一项系统工程。资源型城市转型要解决资源开发过程中所积累的一系列重大经济、社会和环境矛盾,既要充分发挥市场配置资源的基础性作用,又离不开以政府为主导的政策体系的支撑。对此,《中共中央、国务院关于实施东北地区等老工业基地振     

提高学生英语阅读水平

提高阅读能力是促进外语学习的重要手段,快速有效地阅读,不仅能获得大量信息,并可扩大词汇量,增强语感,,使我们的英语水平在总体上获得提高。     

Liner ship fleet deployment with container transshipment operations

This paper proposes a liner ship fleet deployment (LSFD) problem with container transshipment operations. The proposed problem is formulated as a mixed-integer linear programming model which allows container transshipment operations at any port, any number of times, without explicitly defining the container transshipment variables. Experiments on the Asia-Europe-Oceania shipping network of a global liner shipping company show that more than one third (17-22 ports) of the total of 46 ports have transshipment throughputs. Computational studies based on randomly generated large-scale shipping networks demonstrate that the proposed model can be solved efficiently by CPLEX.     

Robust schedule design for liner shipping services

This paper examines the design of liner ship route schedules that can hedge against the uncertainties in port operations, which include the uncertain wait time due to port congestion and uncertain container handling time. The designed schedule is robust in that uncertainties in port operations and schedule recovery by fast steaming are captured endogenously. This problem is formulated as a mixed-integer nonlinear stochastic programming model. A solution algorithm which incorporates a sample average approximation method, linearization techniques, and a decomposition scheme, is proposed. Extensive numerical experiments demonstrate that the algorithm obtains near-optimal solutions with the stochastic optimality gap less 1.5% within reasonable time.     

星辰急便倒闭危机对民营快递的启示

以星辰急便为例,结合时事资料分析其深陷倒闭危机的五大原因：市场定位不准、转型失误、强行并购、缺乏专业人才等。总结出企业投资决策需良好的市场调查,慎重采用加盟模式、加强内部管理等经验,希望国内民营快递企业有所借鉴,减少失败风险。     

多维距离视角下区域专利技术转移影响因素研究

区域创新是促进其经济增长的重要动力，而专利技术转移是区域创新的主要方式之一。将我国区域层面专利技术转移按照转移方向及边界划分为区域外部专利技术流入、流出以及区域内部专利技术流动3个维度，探讨地理距离、经济距离以及产业结构距离等多维距离对上述3个维度区域专利技术转移的影响，以及区域创新环境在上述影响中的调节效应。基于我国2001—2015年区域面板数据，采用Tobit模型对上述影响进行实证检验，得到如下结论：①区域外部专利技术转移明显弱于区域内部专利技术转移，且空间不均衡现象明显；②在多维距离中，产业结构距离对区域专利技术转移具有显著影响且该影响受区域创新环境的调节。产业结构距离增加使得区域内部专利技术流动减少，区域外部专利技术流入与流出增加，且上述作用在区域创新环境较差时尤为明显。最后，基于区域层面提出相关政策建议。     

Using Customer Service to Build Clients’ Trust*

It is well known in the credence-good literature that in an expert-client relationship, under the Liability assumptions, clients have to reject the expert’s serious-treatment recommendations with a positive probability to ensure that the expert honestly recommends treatments. Inefficiency arises because some socially efficient treatments are not provided. We show that the expert can enhance clients’ trust, or acceptance rate of the serious treatment, by providing intrinsically socially inefficient customer service upon recommending the serious treatment. Enhanced clients’ trust leads to higher efficiency and higher profit for the expert. However, trust cannot be enhanced by providing customer service with different timing.     

Opinion Divergence Among Professional Investment Managers

Abstract:  We find that opinion divergence among professional investment managers is commonplace, using a large sample of transaction-level institutional trading data. When managers trade together, future returns are similar regardless if they are all buying or selling, inconsistent with the notion that professional investment managers possess stock picking ability or private information that is of investment value. However, when managers trade against each other, subsequent returns are low, especially for stocks that are difficult to short. This U-shaped disagreement-return relationship is consistent with Miller's (1977) hypothesis that, in the presence of short-sale constraints, opinion divergence can cause an upward bias in prices.