An economic analysis of the Cattlemen’s Beef Promotion and Research Board demand-enhancing programmes

The research reported here addressed two objectives. The first objective was to measure the overall impact of the Cattlemen’s Beef Board as well as eight-specific advertising, promotion and research activities on US beef demand. The second objective was to compute marginal benefit–cost ratios (BCRs) for the eight individual checkoff activities and for the overall programme. The results indicated that Cattlemen’s Beef Board’s Promotion activities increased total domestic beef demand by 15.7 billion pounds in total, or 2.1 billion pounds per year between 2006 and 2014. Collectively, the overall marginal BCR for all Cattlemen’s Beef Board activities was $11.20.     

基于BOTDA的桩体水平位移分布式光纤监测技术

随着城市的发展,城市轨道交通建设成为城市发展中具有重要意义的工程项目。然而由于该项目本身具有高风险性,一旦发生破坏,将产生难以承担的后果,因此如何防止此类事故的发生是目前亟须解决的问题。利用布里渊散射光时域分析（BOTDA）技术,以厦门轨道交通3号线3标段为工程依托,对开挖地铁基坑的围护桩变形进行监测。针对桩体位移,利用材料力学推导水平位移计算公式,并与监测结果进行对比,以验证所提布设方案在基坑监测中的可靠性。     

桩基施工对验潮井变形与内力影响数值分析

桩基施工过程中对土体的挤压与扰动势必对周围土层的位移与内力产生影响,而其影响范围是判断周围已有建构筑物稳定性的重要依据.采用目前在岩土工程领域广泛使用的三维数值模拟软件FLAC3D进行模拟计算,得出桩基施工过程中联合国海洋平面观测站(验潮井)变形与内力变化.计算结果显示:1～16号桩在施工过程中对验潮井竖向与侧向均产生了位移,但位移值较小;最小主应力与最大主应力变化不明显.通过对验潮井的位移与内力的计算,南防波堤平台桩基工程施工应由近及远依次施工,施工时应尽量避免对岩土体的扰动与破坏,不得采用爆破施工,保证基岩完整性.     

Wagner’s law versus displacement effect

The public sector has grown dramatically over the past few centuries in many developed countries. In this article, we use wavelet methods to distinguish between two leading explanations for this growth – Wagner’s law and the displacement effect. In doing so, we use the long-term data of 10 OECD countries for a maximum time span of 1800–2009. We find that the validity of Wagner’s law is likely to vary strongly over time for each country. A roughly similar feature in most of the countries is that the law is less valid in the earliest stage of economic development as well as in the advanced stages, with the validity tending to follow an inverted U-shaped pattern with economic development. Further, our results indicate that the long-run growth of government size cannot be adequately explained by Wagner’s law. On the other hand, the displacement effect appears to account for the bulk of the growth in most of the countries.     

桩筏基础非线性共同作用分析及变刚度调平设计

桩筏基础的承载力、位移特征分析,尤其是建立在桩-土-筏共同作用基础上的以减小沉降差为目的的变刚度调平分析是目前桩筏基础设计的难点与热点。文章利用桩筏基础的非线性共同作用分析方法和分析程序,分析了桩筏基础当筏板厚度和桩距、桩长、桩径变化时,筏板的位移特性和桩顶的反力及其分布规律,得到了一些有意义的结论。利用本文的分析结果,进行桩筏基础的变刚度调平设计,以达到减少桩筏基础筏板沉降差的目的。     

GPS在集输管道异常位移监测技术中的应用

集输管道是石油、天然气的主要运输渠道,承担着能源运输的重大责任。一些重大管线如果发生事故,则给国家造成不可估量的损失。这就迫切需要解决管网事故率高的问题,以减少由此造成的不必要的损失。采用GPS系统来监测长距离集输管道的异常位移,具有全天候、高精度、自动化程度高等特点,并且卫星通信覆盖能力强,信号稳定,相对于人烟稀少的地点,更具有优势。本文介绍了利用GPS(RTK)技术监测集输管道实时位移的方法和实现途径。     

REGIONAL TIES AND DISCRIMINATION: POLITICAL CHANGE,ECONOMIC CRISIS,AND JOB DISPLACEMENTS IN SOUTH KOREA, 1997–99

Probing into the incidence of job displacements during the 1997–99 recession period, this study offers theoretically grounded micro‐causal explanations for regional ties and regional discrimination in South Korea. Our statistical analysis reveals the significant impact of a worker's birth region (the basis of regional ties and discrimination) on the layoff process. Native Kyongsang workers are found to have faced higher rates of layoff in Seoul‐Kyongki regional firms than native Jolla workers during the recession period. The Kyongsang–Jolla layoff rate gap is mainly due to differential treatment rather than a difference in observable characteristics. The findings suggest that the problem of regional ties and regional discrimination is more deep‐rooted and widespread in South Korea than previously reported.     

水平井水力参数优化设计研究

水平井水力参数的优化设计,是指在一口井施工以前,根据水力参数优选的目标,对钻进水平井时的每个井段所采取的钻井泵工作参数(排量、泵压、泵功率等)、钻头和射流水力参数(喷速、射流冲击力、钻头水功率等)进行设计、计算。分析钻井过程中与水力因素有关的各变量可以看出,当地面机泵设备、钻具结构、井身结构、钻井液性能和钻头类型确定以后,真正对水平井水力参数大小有影响的可控参数就是钻井液排量和喷嘴直径。因此,水平井水力参数优化设计的主要任务也就是确定钻井液排量和选择喷嘴直径。     

Profitability of incremental generic promotion of Australian dairy products

The motivation for this study rests on two factors. First, Australian dairy farmers spend around $20 million annually on generic promotion and estimates of the returns from this expenditure are required to facilitate efficient investment decisions. Second, while the Australian dairy industry has been highly regulated, there has been a substantial reduction in assistance over the past decade and farm‐gate milk prices were deregulated on 1 July 2000. The profit potential of promotion may vary with the degree of regulation, so past estimates of the returns from promotion may not hold in the competitive environment of the future. Hence, the aim of this study is to examine the effects of government intervention on the profitability for dairy farmers of incremental changes in generic dairy promotion expenditure using a perfectly competitive market as a reference point. Competitive market price and quantity outcomes for the Australian dairy industry are estimated. The impacts of increments in dairy product and competing product generic promotion expenditures on dairy farmers’ profits are assessed using equilibrium displacement modelling. Finally, graphical procedures are used to examine the effects of dairy industry regulation on the profitability of dairy promotion.     

Sister Communities: Rejecting Labels of Informality and Peripherality in Vanuatu

Some labels have dire consequences. This article takes issue with the labels commonly used to describe the physical and social location of communities living on the edge of Port Vila, Vanuatu—labels that position communities for eviction by entrenching tropes of informality and peripherality into how they are seen and represented. Such terms include informal, settlement, informal settlement, squatter and peri-urban. Based on interviews with around 100 people and two years of ethnographic engagement with urban communities in Port Vila, Vanuatu, I critique the language of policy against the lived experience of those at the urban edge. I use Bourdieu's articulation of power as an accumulation of symbolic capital that enables one to speak the world into being. I conclude that the language of policies and plans is reflective of a dominant discourse in urban studies and international aid, and non-reflective of the experience and identities of people living at the urban edge. My interviewees and interlocutors maintain their identities as sister communities—as places grounded in the formality of customary tenure, and as part of the city rather than outside it.