快递企业航空货运网络的构建

快递业竞争激烈,构建高效合理的航空货运网络是快递企业提高竞争力的重要手段。“枢纽—辐射”式航空货运网络是整合航空快递资源、提高航空快递资源利用效率、提高快递企业竞争力的有效模式。本文以降低航空快递网络成本、加快航空快递处理时间为目标,从航空快递网络枢纽的选取、指派关系的确定、枢纽个数的选择三个方面研究了航空快递网络模型建立问题,选用遗传算法求解不同枢纽个数下航空快递网络的运输成本,并据此进行枢纽的选取,运用重力模型法进行指派关系的确定,在此基础上运用超效率DEA模型确定枢纽个数。接着,以包含17个节点的顺丰航空快递网络的规划为例,对本文所提出的模型和算法进行了验证,验证结果证实了模型的合理性。本文的研究为快递企业构建航空货运网络提供了科学实用的方法,该方法的使用可以降低航空货运成本,提高效率,从而提高快递企业的竞争力。     

上海股票市场收益的随机波浪模型

对金融资产收益分布状况的主要研究方法是先提出分布模型,然后进行实验验证;因缺乏必要的机理分析和研究手段单一,使其理论研究和应用研究都受到一定的制约.为克服这些不足,将金融资产收益联系起来看,根据其涨跌周期性构建出随机波浪模型,并利用模型导出随机波浪波高和周期的分布公式.通过实证分析,证明随机波浪模型具有一定的适用性;所用的时频分析方法以及所得结论有益于对金融资产收益分布状况进行更深入的理论和应用研究,也有益于指导市场参与者进行短期和长期交易.     

波士顿矩阵法在河南承接产业转移中的应用

承接产业转移是加速区域经济发展的"助推器",提升产业集聚能力是提高区域产业竞争力的关键,如何科学地选择承接产业,并提升产业集聚能力是河南亟待解决的问题.选取2010年和2014年两个时点,运用产业梯度系数和产业动态集聚指数对工业进行分行业分析,并借鉴波士顿矩阵分析法将其划分为明星、金牛、问题、瘦狗和衰退等产业.根据河南的自然资源、劳动力、区位条件、市场需求等比较优势,并考虑产业集聚发展的能力,来确定河南承接产业转移的重点产业.     

Recent optimization models and trends in location,relocation, and dispatching of emergency medical vehicles

Over the past 10 years, a considerable amount of research has been devoted to the development of models to support decision making in the particular yet important context of Emergency Medical Services (EMS). More specifically, the need for advanced strategies to take into account the uncertainty and dynamism inherent to EMS, as well as the pertinence of socially oriented objectives, such as equity, and patient medical outcomes, have brought new and exciting challenges to the field. In this context, this paper summarizes and discusses modern modeling approaches to address problems related to ambulance fleet management, particularly those related to vehicle location and relocation, as well as dispatching decisions. Although it reviews early works on static ambulance location problems, this review concentrates on recent approaches to address tactical and operational decisions, and the interaction between these two types of decisions. Finally, it concludes on the current state of the art and identifies promising research avenues in the field.     

A Laboratory,Computer and Calculus Based Course in Mathematics

The paper describes the designing and testing of a laboratory, computer and calculus based course in mathematics. The laboratory is central to the course and stimulates in the student the need and desire to know more about mathematics. Further, it enables mathematics to be taught in a real world context. Computers are used to take the drudgery out of the mathematics and make it possible to attack real scientific and technical problems. This new approach to calculus is less formal and depends to a smaller extent upon prior mathematical training so that it appeals to a much wider audience. The proposed course, with its emphasis on laboratory measurements, is ideally suited to the exploration of numerical methods and their application to the calculation of derivatives, definite integrals and the solution of differential equations.     

Imprecise stochastic orders and fuzzy rankings

We extend the notion of stochastic order to the pairwise comparison of fuzzy random variables. We consider expected utility, stochastic dominance and statistical preference, which are related to the comparisons of the expectations, distribution functions and medians of the underlying variables, and discuss how to generalize these notions to the fuzzy case, when an epistemic interpretation is given to the fuzzy random variables. In passing, we investigate to which extent the earlier extensions of stochastic dominance and expected utility to the comparison of sets of random variables can be useful as fuzzy rankings.     

Students’ self-regulation of emotions in mathematics: an analysis of meta-emotional knowledge and skills

Over the past decade, the concept of self-regulated learning has broadened to include motivational, volitional, and emotional components next to (meta-)cognitive ones. In this article, we present a meta-emotion perspective as an essential component of a conceptual framework on self-regulation that fully acknowledges the role of emotions. Against this background, a study is presented that attempts to contribute to the clarification of the relevance and the functioning of students’ meta-emotional knowledge and emotional regulation skills in school-related mathematical activities. It investigates the coping strategies that 393 students of the second (age 14) and fourth (age 16) year of secondary school report to use to regulate their emotions in three different mathematical school settings (i.e., a mathematics test, a difficult mathematics homework, and a difficult mathematics lesson). More specifically, it aims (1) to document the nature and frequency of the reported coping strategies, and (2) to explore—for the three different mathematical school settings—relationships between these reported coping strategies and personal characteristics (i.e., students’ familiarity with the particular school settings, their track in secondary education, their achievement level, their age, and gender). The results indicate that students report to know and to make use of several coping strategies in school-related mathematical activities, and reveal that the use of these strategies is related to specific person-related characteristics. In conclusion, we elaborate on how schools and teachers can stimulate students to acquire appropriate strategies and skills to self-regulate their emotions.     

基于主客观信息综合判断的非线性拉开档次法

针对以最大程度的拉开被评价对象间差异的综合评价问题,通过分析线性拉开档次法存在的局限性,本文提出了一种基于主客观信息综合判断的非线性拉开档次法,旨在进一步丰富和完善拉开档次法的理论知识。首先对线性拉开档次法进行简单的介绍,并分析了线性拉开档次法的局限性;然后提出前提假设,给出非线性因子选取的原则以及确定指标序关系的方法,并给出排序后相邻指标重要程度比值的选取方法,根据评价原则利用规划模型求解各评价指标的权重系数,利用求得的指标权重采用非线性集结模型计算最终的评价结果;最后用一个算例验证了方法的有效性。     

The effective communication of system dynamics to improve insight and learning in management education

Experienced exponents of system dynamics in management education appreciate that feedback, non-linearities and delays are ubiquitous, and create difficulties for making intuitive judgements about the dynamic behaviour of business systems. They have applied much effort to solving this problem, offering simple, high-level causal mapping techniques to conceptualise dynamic issues, formal simulation modelling, and simulation-based learning environments. However, the use of these methods is still not extensive, and it is often disconnected from other management development pedagogies.System dynamics is ideally suited to operationalising certain concepts central to the management field, notably the resource-based and competence-based view of strategic management. However, three developments must be made if this potential is to be exploited. Firstly, system dynamics must connect with those established concepts and frameworks in the management field. Secondly, the barriers for managers to appreciate the power of system dynamics must be lowered, to make the method an integral part of the managerial mind-set. Thirdly, managers need help to climb the learning curve of understanding regarding the dynamic behaviour of the business systems they endeavour to manage, through a comprehensive set of resource-mapping and gaming simulation tools.This paper describes how these developments can be implemented, reports on experience of using the resulting learning devices and comments on possible future directions. There is an exciting opportunity for system dynamics to make a major contribution to a new strategy paradigm, based on a dynamic resource-system view of the firm, a perspective that can be extended to other fields in management and to non-business contexts.     

The Implications of Cognitive-style Findings for Operational Research

Cognitive style refers to differences that can be perceived in individuals due to differing cognitive structures. There has been a large amount of research on how cognitive style affects managerial decision-making, particularly in the context of management information systems, but little or no attempt to relate these findings to operational research. This paper reviews the findings of cognitive-style research from the perspective of operational research, and draws a number of useful inferences concerning the matching of OR aids to managers, the presentation of information and recommendations, the use and acceptance of OR, and the structure of OR groups. Further, it is argued that cognitive-style findings help to give a justification to the move towards ‘soft’ approaches to analysis.     

居民生活私人交通碳排放驱动因素的“三级分解”模型

突破以往采用难以保证精确性估算数据的局限,根据居民生活私人交通所消耗的能源种类,利用官方统计年鉴中的数据,在保证数据真实性的基础上,基于扩展的IPAT与LMDI模型,构建一个包含居民私人交通碳排放强度、碳排放结构、交通消费倾向、收入、家庭规模与户数6个因素的居民私人交通碳排放驱动因素的"三级分解模型",对居民生活私人碳排放及其驱动因素进行核算.结果建议进一步降低居民私人交通碳排放强度,提高居民能源消费的利用效率;同时鼓励发展小排量与新能源汽车消费,并且大力发展公共交通,倡导居民出行多采用公共交通工具出行,引导节能减排的出行方式.     

基于STEP-FRAM的机坪保障车辆事件分析

为了克服传统事件分析方法解决单一因素、相对简易系统故障引发的事件的不足,利用STEP-FRAM模型对机场停机坪保障车辆的不安全事件进行了系统分析,结果表明:使用这种方法可以找出导致机场保障车辆不安全事件的功能共振及其影响因素,解释事件的原因和过程,从而设计出预防和控制措施,降低机坪保障车辆不安全事件再次发生的风险.     

Método numérico para la evaluación holística del riesgo sísmico utilizando la teoría de conjuntos difusos

The fuzzy set theory offers a bridge between the symbolic and numerical processing, allowing managing qualitative concepts useful in the decision-making process related to the seismic risk management and, in general, to the disaster risk management. Its use in the seismic risk evaluation is necessary in the cases where the data required to apply a conventional method of assessing risk are not available or are insufficient. One possible solution, considered in this article, is to replace the missing information by expert opinions and to process the resulting qualitative variables and linguistic qualifications instead of numerical values. This process is based on the fuzzy set theory. In order to achieve an effective management, the risk must be defined as the potential physical, economic, social and environmental consequences which occur due to hazards in a given period of time. From this holistic perspective and using the fuzzy set theory, the proposed numerical method calculates a level of the physical risk and level of the aggravating conditions related to social fragility and to the lack of resilience, to determine a total risk level. In the article are included two examples of application of the proposed method and the obtained results are compared with those corresponding to a conventional method of holistic evaluation.     

The utility of returns to scale in DEA programming: An analysis of Michigan rural hospitals

In 1984, Banker, Charnes, and Cooper introduced the capability of using data envelopment analysis to assess increasing, decreasing, or constant returns to scale. This analysis would appear to make an important contribution to the health care field because of the regulatory environment within which the industry exists and the competition among hospitals for additional services and capacity. In many states, hospitals must submit a “certificate of need” to prove eligibility to add capacity or services. Agency administrators at the state level should analyze each hospital's production performance to determine the effectiveness of resource utilization. Residents of a state where hospitals are regulated need to know the effectiveness of agencies in allowing resources to be properly allocated to hospitals. Returns to scale analysis can help provide answers to these concerns. We examine Michigan rural hospitals and propose a simple, yet logical procedure for evaluating returns to scale for technically inefficient hospitals.     

Global existence and asymptotic behavior of solutions to the nonisentropic bipolar hydrodynamic models

In this paper, we consider a one-dimensional bipolar nonisentropic hydrodynamical model from semiconductor devices. This system takes the nonisentropic Euler-Poisson form with electric field and frictional damping added to the momentum equations. First, we prove global existence of smooth solutions to the Cauchy problem. Next, we also discuss the asymptotic behavior of the smooth solutions. We find that in large time, the densities of electron and hole tend to the same nonlinear diffusive wave, the momentums tend to the Darcy's law, and the temperatures tend to the ambient device temperature. Finally, we can obtain the algebraic decay rate of the densities to the same nonlinear diffusive wave, the momentums to the Darcy's law and the temperatures to the ambient device temperature, and the exponential decay of their difference and the electric field to zero. We can show our results by precise energy methods.     

Capturing preferences for inequality aversion in decision support

We investigate the situation where there is interest in ranking distributions (of income, of wealth, of health, of service levels) across a population, in which individuals are considered preferentially indistinguishable and where there is some limited information about social preferences. We use a natural dominance relation, generalised Lorenz dominance, used in welfare comparisons in economic theory. In some settings there may be additional information about preferences (for example, if there is policy statement that one distribution is preferred to another) and any dominance relation should respect such preferences. However, characterising this sort of conditional dominance relation (specifically, dominance with respect to the set of all symmetric increasing quasiconcave functions in line with given preference information) turns out to be computationally challenging. This challenge comes about because, through the assumption of symmetry, any one preference statement (“I prefer giving $100 to Jane and $110 to John over giving $150 to Jane and $90 to John”) implies a large number of other preference statements (“I prefer giving $110 to Jane and $100 to John over giving $150 to Jane and $90 to John”; “I prefer giving $100 to Jane and $110 to John over giving $90 to Jane and $150 to John”). We present theoretical results that help deal with these challenges and present tractable linear programming formulations for testing whether dominance holds between any given pair of distributions. We also propose an interactive decision support procedure for ranking a given set of distributions and demonstrate its performance through computational testing.     

The Unity Game–Reflections of a Faculty Moderate

Change is a perennial struggle for campuses. Trustees, presidents, policymakers, faculty, staff, students, alumni, and community groups all seek to alter some aspect of colleges and universities. Common wisdom is that higher education faculty, staff, and administrators do not want to change and are slow to innovate. This article examines the challenges of change from a macro perspective, using insights from studies of change and leadership, and the perspective of change agents, to provide a new hypothesis of why change is difficult: the presence of too many simultaneous and competing change initiatives, not the unwillingness of campus constituents to engage in change, prevent progress. Concentrated institutional action is impeded by too many stakeholders interested in different types of change, a lack of synergy among change initiatives, an inability to create priorities, leadership turnover, a pressure for leaders to innovate rather than implement, and the movement away from core institutional purposes in the pursuit of prestige.     

Optimal structural design of a planar parallel platform for machining

Parallel manipulators have many advantages over traditional serial manipulators. These advantages include high accuracy, high stiffness and high load-to-weight ratio, which make parallel manipulators ideal for machining operations where high accuracy is required to meet the requirements that modern standards demand.Recently, the finite element method has been used by some workers to determine the stiffness of spatial manipulators. These models are mainly used to verify stiffness predicted using kinematic equations, and are restricted to relatively simple truss-like models. In this study, state-of-the-art finite elements are used to determine the out of plane stiffness for parallel manipulators. Euler–Bernoulli beam elements and flat shell elements with drilling degrees of freedom are used to model the platform assembly.The main objective of this study is to quantify the stiffness, particularly the out of plane stiffness, of a planar parallel platform to be used for machining operations. The aim is to obtain a design that is able to carry out machining operations to an accuracy of 10 μm for a given tool force.Reducing the weight of a parallel manipulator used in machining applications has many advantages, e.g. increased maneuverability, resulting in faster material removal rates. Therefore the resulting proposed design is optimized with respect to weight, subject to displacement and stress constraints to ensure feasible stiffness and structural integrity. The optimization is carried out by means of two gradient-based methods, namely LFOPC and Dynamic-Q.     

中国煤层气的产业化进程与发展建议

煤层气产业在中国能源建设中具有重要战略地位。中国煤层气勘探开发历经矿井瓦斯抽排利用、现代煤层气理论技术的引进发展与成功应用、商业化开发试验及产业化发展（初期）4个阶段。由于在煤层气地质基础理论、勘探技术方法、开发工艺技术、集输利用与管理制度等方面的发展创新、系统集成,我国已有能力大规模发展煤层气产业,这在我国能源发展战略上是非常难得的历史机遇。当前,为了加快煤层气产业的发展,必须加强统筹规划,发挥多种积极性;加强煤层气地质研究、提高对区域勘探的指导与目标评价水平;开展高效低成本开发工艺技术攻关;发展煤层气产品集输和加工利用;继续跟踪国外煤层气前沿理论技术,加强技术交流与合作研究。     

Feature-Inclusion Stochastic Search for Gaussian Graphical Models

We describe a serial algorithm called feature-inclusion stochastic search, or FINCS, that uses online estimates of edge-inclusion probabilities to guide Bayesian model determination in Gaussian graphical models. FINCS is compared to MCMC, to Metropolis-based search methods, and to the popular lasso; it is found to be superior along a variety of dimensions, leading to better sets of discovered models, greater speed and stability, and reasonable estimates of edge-inclusion probabilities. We illustrate FINCS on an example involving mutual-fund data, where we compare the model-averaged predictive performance of models discovered with FINCS to those discovered by competing methods.