客运专线32 m箱梁徐变效应研究

针对已建成通车的武广、沪杭客运专线两种32 m跨预应力混凝土箱梁,对比分析施工阶段梁体跨中上拱变形实测数据,探讨箱梁在施工阶段的徐变特性。在此基础上,应用MIDAS/Civil分析软件,采用ACI 209R收缩徐变计算模式,根据设计图纸和施工控制要求,建立梁体有限元模型,对比两种箱梁的徐变变形,与实测结果互为验证,预测二恒铺装对梁体变形影响和铺装后期徐变变形。结果表明,沪杭客专32 m梁徐变变形较武广客专32 m梁小,变形控制措施更为完善。     

The Origin and Role of Trust in Local Policy Elites’ Perceptions of High‐Voltage Power Line Installations in the State of Arkansas

The debate over an installation of high‐voltage power lines (HVPLs) has been intense, particularly in northwest Arkansas. Detractors claim that the installation will negatively affect both the natural environment and the local economy, which contains a large tourism component. By contrast, those in favor of installing HVPLs claim that the installation is necessary in order to reliably support the increasing demand for electric power. Using original data collected from a recent statewide Internet survey of 420 local policy elites in Arkansas, this article focuses on two key aspects. First, we examine how local policy elites’ perceptions of risks versus benefits of HVPL installation in their communities are influenced by their levels of trust toward information provided by various sources (e.g., energy industry, environmental groups, and government). Second, we utilize cultural theory to explain how the cultural worldviews of policy elites––specifically, egalitarianism, individualism, hierarchism, and fatalism––shape these levels of trust and HVPL benefit‐risk perceptions, while controlling for other factors claimed by previous literature, including levels of knowledge on energy‐related issues and demographic characteristics. In general, our analysis indicates that policy elites’ value‐oriented formation of HVPL benefit‐risk perceptions is partially due to the influence cultural values have on trust in information sources. We conclude this article by discussing broader implications for the origin and role of trust in policy elites’ decisions throughout the policy‐making process.     

“These Power Lines Make Me Ill”: A Typology of Residents’ Health Responses to a New High‐Voltage Power Line

Little attention has been devoted to the potential diversity in residents’ health responses when exposed to an uncertain environmental health risk. The present study explores whether subgroups of residents respond differently to a new high‐voltage power line (HVPL) being put into operation. We used a quasi‐experimental prospective field study design with two pretests during the construction of a new HVPL, and two posttests after it was put into operation. Residents living nearby (0–300 m, n = 229) filled out questionnaires about their health and their perception of the environment. We applied latent class growth models to investigate heterogeneity in the belief that health complaints were caused by a power line. Classes were compared on a wide range of variables relating to negative‐oriented personality traits, perceived physical and mental health, and perceptions of the environment. We identified five distinct classes of residents, of which the largest (49%) could be described as emotionally stable and healthy with weak responses to the introduction of a new power line. A considerable minority (9%) responded more strongly to the new line being activated. Residents in this class had heard more about the health effects of power lines beforehand, were more aware of the activation of the new line, and reported a decrease in perceived health afterwards. Based on our findings we can conclude that there is a considerable heterogeneity in health responses to a new HVPL. Health risk perceptions appear to play an important role in this typology, which has implications for risk management.     

Performance Analysis of Exponential Multi-Server Production Lines with Fluid Flow and Finite Buffers

This article presents an approximation method for fluid flow production lines with multi-server workstations and finite buffers. Each workstation consists of parallel identical servers, which are subject to operation-dependent failures with exponentially distributed uptimes and downtimes. The proposed method decomposes the production line into single-buffer subsystems, each described by a continuous state Markov process, the parameters of which are determined iteratively. The approximation method is appropriate for the analysis of longer production lines, able to accurately estimate performance characteristics (e.g., throughput and mean buffer content), and shown to perform well on a large test set.     

群在时空之间:论明代土司的民族族系分布特点

本文在土司族属理论研究基础上对我国明代土司的族属分布、群分布、时间分布和空间分布做出了基本分析,揭示了民族政治文化的同一性以及多元性、多样性特点.文章认为在明帝国辽阔版图内有26个少数民族存在着土司,而且形成四大土司集群,各民族土司内部存在数量不等的土司类型,不同类型之间不断发生转化.对土司的民族族系进行断代清理,可以强化土司学的跨民族文化研究的功能,有效地实现土司学和民族史学科的对接与转换.     

线在建筑速写中的运用

用线造型是建筑速写的主要表现方法，对线的造型性、线的节律性以及线的表现力进行了讨论，阐述了线在建筑速写中所起到的重要作用。     

Quantity Constraints, Poverty Lines and Poverty Orderings

By limiting the scope for substitution between commodities, other things equal quantity constraints raise the cost of living. Thus, rationed families have higher povery lines than unconstrained ones. This heterogeneity in both resources and poverty lines means that, in principle, bivariate dominance results are required to order distributions in terms of poverty.     

GPS在输电线路双端量故障测距中的应用

双端量故障测验需要同步采样 .分析了故障测距对同步时钟的要求 ,介绍了GPS的特点 ,给出了GPS在输电线路双端量故障测距中应用的初步方案     

球形凸模胀形时胀形力分析计算

本文从理论上研究了球形凸模胀形过程中正应力沿子午面（θ）方向的分布状况．从塑性力学出发．推导出了胀形力的计算公式，对公式作了说明并提出了一些建议．     

《易传》的道德观发微

《易传》是我国先秦时期一部专门解释《易经》的重要典籍,在其无比丰富的内容中,透露了相当深刻的道德观念:一是对《易经》所包含的道德观念进行了创造性阐发;二是大力倡导一些具有积极意义的道德精神;三是提出了一些具有积极意义的修身原则,这些都对我们民族的道德理论和道德实践产生了极其深远的影响。