基于鲁棒性的关键链二次资源冲突消除策略

以关键链方法中的二次资源冲突困境为切入点,从鲁棒调度优化角度提出一种解决策略.首先,采用定量化建模对问题进行数学描述和表达,剖析插入输入缓冲引起二次资源冲突的原理,进而采用场景分析法从复杂的冲突表象中分解出四种基本的冲突场景构成要素.其次,基于鲁棒调度优化理论,探究各种冲突子问题的有效对策并归类,据此开发出一种消除二次资源冲突的局部重调度启发式协调策略;根据策略设计基于两次调度进程和两类缓冲动态消耗的鲁棒性指标,采用鲁棒性关键链项目调度问题输出鲁棒性最大的调度方案.再次,设计仿真程序和三个测试指标:项目实际按期完工率、活动开始时间偏差绝对值之和及偏差绝对值的方差;基于ProGen随机地生成测试算例集合进行数值实验.结果发现,以鲁棒性调度方案为依据安排项目的实施过程,三个统计指标值都优于以传统关键链调度方案为依据时相对应的指标值.结论表明:基于鲁棒调度优化的二次资源冲突消除策略及设计的关键链鲁棒性指标在项目实施中具有较好的稳定性效果.     

Planners’ Perceptions of Why Canadian Communities Have Too Many Plans

A survey of Canadian planners explored perceptions about factors contributing to the growing number of plans communities have adopted recently. The results suggest that practitioners see themselves as responding to current community concerns, as well as to requirements imposed by higher levels of government. Neoliberal practices that force compliance with accountability frameworks to enable transfer payments increase demands for new plans. Professional practices within planning have encouraged specialization—in fields such as urban design—that often leads to plan-making activities. With many plans to coordinate, and limited staff resources and time available, practitioners face increasing implementation challenges.     

Expatriate contact with a local host: an intervention to increase social support

Social capital is a crucial factor for expatriates to employ as they cope with the demands of an international assignment. This longitudinal study used a mixed method approach to examine the social support benefits of expatriate contact with a local host. Western expatriates in the Netherlands were randomly divided into two groups: an experimental group (n = 33), that had contact with a Dutch host during 9 months, and a control group (n = 32) with no host. Qualitative methods such as interviews and diaries were included to shed light on the various types of social support that occurred. Results show that local hosts offered all four types of social support: social companionship, informational support, emotional support, and instrumental support. Furthermore, expatriates with a host increased their social capital; they received significantly more social support from host nationals than did those without a host. This study shows that HRD professionals may develop the social capital of expatriates by bringing them into contact with a local host, which can produce more social support from host nationals. Increased social capital may lead to a higher performance at both the individual and organisational levels.     

Program Evaluation and Causal Inference With High‐Dimensional Data

In this paper, we provide efficient estimators and honest confidence bands for a variety of treatment effects including local average (LATE) and local quantile treatment effects (LQTE) in data‐rich environments. We can handle very many control variables, endogenous receipt of treatment, heterogeneous treatment effects, and function‐valued outcomes. Our framework covers the special case of exogenous receipt of treatment, either conditional on controls or unconditionally as in randomized control trials. In the latter case, our approach produces efficient estimators and honest bands for (functional) average treatment effects (ATE) and quantile treatment effects (QTE). To make informative inference possible, we assume that key reduced‐form predictive relationships are approximately sparse. This assumption allows the use of regularization and selection methods to estimate those relations, and we provide methods for post‐regularization and post‐selection inference that are uniformly valid (honest) across a wide range of models. We show that a key ingredient enabling honest inference is the use of orthogonal or doubly robust moment conditions in estimating certain reduced‐form functional parameters. We illustrate the use of the proposed methods with an application to estimating the effect of 401(k) eligibility and participation on accumulated assets. The results on program evaluation are obtained as a consequence of more general results on honest inference in a general moment‐condition framework, which arises from structural equation models in econometrics. Here, too, the crucial ingredient is the use of orthogonal moment conditions, which can be constructed from the initial moment conditions. We provide results on honest inference for (function‐valued) parameters within this general framework where any high‐quality, machine learning methods (e.g., boosted trees, deep neural networks, random forest, and their aggregated and hybrid versions) can be used to learn the nonparametric/high‐dimensional components of the model. These include a number of supporting auxiliary results that are of major independent interest: namely, we (1) prove uniform validity of a multiplier bootstrap, (2) offer a uniformly valid functional delta method, and (3) provide results for sparsity‐based estimation of regression functions for function‐valued outcomes.     

基于非参数时变Copula模型的美国次贷危机传染分析

金融危机传染分析是国际金融领域中的重要课题,本文对Copula变点检测方法进行推广,采用时变非参数阿基米德Copula模型检验金融危机传染的存在性及其变化趋势,以时变尾部相依系数的大小来度量危机传染程度,并结合系数的变化趋势和时间段对金融危机传染效应进行分析.最后选择全球六个主要股票市场指数和S&P500指数进行危机传染实证研究,得出次贷危机对不同国家或地区的传染效应有所差别.     

Forest Fire Risk Management and Public Participation in Changing Socioenvironmental Conditions: A Case Study in a Mediterranean Region

Under current conditions of accelerated socioenvironmental change in the Mediterranean forested landscapes, fire is one of the most critical and difficult risks to tackle within the region. This article summarizes the lessons learned from a project based on the participatory integration of qualitative local stakeholders' knowledge with expert GIS fire simulations carried out in the County of El Bages, Catalonia, Spain. First, in this article, a theoretical model--the forest fire circle--is presented in order to explain the reasons for the rise in the damage and frequency of forest fires in this Mediterranean area. Second, it describes the methodology developed and the stages followed during the project. Results show that: (1) the advocacy of old forest reactive management paradigm assumptions and practices based on uncontrolled forest succession can put vast wooded areas of the Mediterranean basin at critical risk; and (2) forest fire management approaches that ignore the crucial role of long-term prevention and local capacity building strategies have failed. In the final section, the content and the specific dimensions of the old reactive paradigm that has characterized forest fire risk management in Catalonia are discussed and contrasted with the possibly emerging preventative paradigm.     

从平宁藩之役看王守仁的军事思想

王守仁善于从政治角度去处理军事问题,在战争指导思想上十分重视谋略,在建军思想上强调选将用将,并将因材施教原则应用于军事训练．他将心学运用于军事之中是其军事思想最具特色之处．阳明心学虽属唯心主义体系,他的军事思想却具有唯物主义倾向．     

安大简《诗经》“侯六”“魏九”浅析

通过分析《毛诗·魏风》《唐风》诸篇的诗旨和安大简自身的特点,认为安大简《侯》《魏》两部分内并无“误置”现象。又从战国初期的历史背景出发,并结合诗旨、春秋战国时期的“用诗”特点,赞成安大简《魏》之所以抄写《毛诗·唐风》中的诗篇,当与战国时期魏国国力强盛、占有晋国故地相关。由于抄写《唐风》诗篇的部分被称为“魏”,因此,抄写《魏风》的部分就不能再称为“魏”,必须改题。从《毛诗》诸国风的命名逻辑看,“侯”极可能是地名。不过,若考虑到安大简的特点,“侯”为爵位也未尝不可。从安大简《侯》《魏》的特殊安排看,它无疑是一个改编本,其底本与《毛诗》应该非常接近。     

地方党政主要领导职位空缺的现状、成因及对策

地方党政主要领导职位空缺是指在领导干部选任和调配过程中,由于诸多常规或非常规原因导致某一地区的党委或政府部门主要领导职位在较长时间内空缺,进而直接或间接影响地方党政工作的特殊现状,广泛存在于各级、各地党政部门。由于我国有关干部职位空缺的制度建设和管理规范尚不完善,地方党政主要领导职位空缺产生一些消极影响,主要表现为不利于地方党政机关运行,存在腐败风险,触发舆论风险等。在充分认识空缺危害性的基础上,深入分析造成职位空缺的干部调配因素、选任导向变革因素以及其他非常规因素等,从完善遴选机制、衔接制度、保障机制、舆论生态治理、干部教育等五个方面切实解决地方党政主要领导职位空缺带来的一系列问题。     

少数民族地区水利水电工程移民问题探讨

西部少数民族地区是我国水利水电开发的重点区域。少数民族地区移民的特殊性对移民安置的实施提出了挑战。综合利用文献和田野经验,在梳理少数民族地区移民安置主要研究领域的同时,分析了研究的前沿科学问题。已有研究主要围绕少数民族地区移民的搬迁补偿、移民安置、移民适应、移民融合等问题。后续研究中,需要关注少数民族人地关系与生计、少数民族宗教信仰与文化习俗及其恢复补偿、少数民族移民可持续发展研究等。