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1.
In horticultural markets, trade barriers often apply to the processed products whereas domestic support applies to farm-produced raw commodities. Here we assess the effects of such trade barriers and domestic support by simulating the effects of policy reform on global processing tomato markets, which are faced with modest processed product tariffs and high domestic support in the European Union (EU). Both protection and EU subsidy drive down world welfare, but we find that reducing import tariffs for tomato products would yield greater effects on markets and larger welfare impacts outside Europe than would reductions in EU domestic support.  相似文献   
2.
对一种已经通过试验研究的钢管混凝土结构的新型节点进行数值分析。这种节点将钢管混凝土柱的钢管在节点区间断,在节点区设置芯钢管,使梁中的纵筋在节点中直通、梁与节点区混凝土成为一体可靠的传递梁中的弯矩、剪力及轴力。本文利用数值分析弥补模型试验数量少的缺陷。选择不同芯钢管壁厚的节点模型进行非线性有限元分析,得出芯钢管壁厚对节点承载力的影响规律。分析结果表明芯钢管壁厚是影响节点承载力的主要因素之一。  相似文献   
3.
用拉格朗日方程导出离心摆式减器精确的运动微分方程,并根据工程实际中挂摆式减振器结构,提出考虑平行四边形效应的运动微分方程的修正。  相似文献   
4.
Schlichtman and Patch suggest that there is an elephant sitting in the academic corner: while urbanists often use ‘gentrification’ as a pejorative term in formal and informal academic conversation, many urbanists are gentrifiers themselves. Even though urbanists have this firsthand experience with the process, this familiarity makes little impact on scholarly debate. There is, Schlichtman and Patch argue, an artificial distance in accounts of gentrification because researchers have not adequately examined their own relationship to the process. Utilizing a simple diagnostic tool that includes ten common aspects of gentrification, they compose two autoethnographic memoirs to begin this dialogue.  相似文献   
5.
Gentrification in China is intertwined with urban redevelopment, which causes the large‐scale displacement of rural–urban migrants from ‘villages in the city’ (ViCs). Because of the informality of ViCs, migrant renters have very insecure tenancy and during redevelopment they are treated as a negligible (‘invisible’) social group. As they are very difficult to locate after displacement, they are also literally invisible to researchers. To make the invisible visible, this study traced a sample of displaced migrants from Huangbeiling village in Shenzhen. The focus was on the displacement process and on identifying the consequences for the displaced. We found various forms of displacement during the redevelopment process. Nearby ViCs were prioritized by displaced migrants to minimize as much utility loss as possible. However, they generally suffer from decreased proximity, increased living costs, and the loss of social networks and job opportunities. Remarkably, some choose to return to the gentrifying village, enduring displacement in situ caused by increasing rents, drastic physical neighbourhood changes and declining liveability, in exchange for retaining their original social and economic networks. Large‐scale urban redevelopment is causing the rapid shrinkage of informal housing. Recognizing and addressing the housing needs of this impoverished social group is a matter of urgency.  相似文献   
6.
Abstract:

Through a comprehensive review of the progressive institutional change (PIC) literature, I first discuss four possible trajectories of PIC by considering the forces of societal reaction that might frame the path, as well as the scale and scope of the changes. Thus, I pose four questions that need to be asked when related policies are formulated for PIC. To illustrate this method, I scrutinize the evidence from the construction of a socialist market economy by the Chinese government since the 1980s and argue that related policies have successfully promoted PIC from three dimensions: (1) curbing potential conflicts with power groups; (2) promoting a sense of awareness among stakeholders; and (3) minimizing disturbances to the community. Actually, the related changes demonstrate a dynamic “displacement process” for PICs. Despite the success of this sociosystem, it is found that the sustaining of PIC which requires policy factors that enhance instrumental efficiency in the Chinese context will serve as a challenge to the Chinese government ahead.  相似文献   
7.
刘海林 《价值工程》2015,(12):57-60
养老地产在我国是一项新兴产业,作为该类建筑中的一个重要组成部分——供暖、通风与空气调节工程,其设计合理与否,对于居住环境和老年人身体健康的影响至关重要。设计人员为了力求打造一个更为适合老年人居住的建筑环境,结合具体工程,做了较为细致的探讨。文章对工程设计方案,包括采暖、空调方式,室内空气质量的控制,气流组织,工程材料选择,振动噪声控制,共五大方面,逐一作了介绍。  相似文献   
8.
王小存 《价值工程》2013,(28):61-62
本文对汽轮发电机振动超标原因进行了分析,并对预防振动超标措施进行了探讨,为汽轮发电机安装人员提供借鉴参考。  相似文献   
9.
周玉丰 《价值工程》2011,30(19):41-43
为了对柴油机故障类型进行准确诊断,对柴油机缸盖振动信号进行特征提取,所测取的信号通过小波变换提取时域、频域特征参数,得到相应的拟合曲线并计算多项式系数。设定两种常见故障,通过比较其小波变换拟合多项式系数与标准模式间的距离,从而判断出故障类型。经过验证,所判断出的故障类型正好为所设定的故障,由此表明该方法具有很大的优越性。  相似文献   
10.
静电除尘器是一种高效的除尘器,已被越来越多的炼钢厂转炉所采用.为了保持静电除尘器长期、高效、稳定地运行,应该对影响静电除尘器除尘效率的因素进行分析,并加强对静电除尘器运行、维护和检修的管理.  相似文献   
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