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21.
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Angie Fredrickson 《Coastal management》2013,41(3):258-271
Consistent with the policies set forth in the Coastal Zone Management Act, the California Coastal Act seeks to balance the utilization and conservation of coastal resources, taking into account the social and economic needs of the citizens of California. One way the statute pursues this balance is through its provisions for ports. These provisions have functioned as a type of smart growth planning for ports, encouraging densification of existing port districts and possibly averting maritime commercial and industrial sprawl along the California coast. One unintended consequence of the encouraged consolidation of port activities, when combined with the rapid growth in international trade over the last four decades, has been disproportionally large environmental and health impacts on low-income and minority communities surrounding ports. This article examines how the Port of Long Beach's conformance with the California Coastal Act has resulted in ongoing environmental justice concerns. It discusses approaches employed by the Port of Long Beach to reduce environmental justice concerns resulting from significant and unavoidable environmental impacts and offers suggestions for how to address this issue. 相似文献
23.
介绍了既有线钢轨焊接接头焊后热处理、矫直及外形精整综合处理系统的总体结构、主要技术参数和性能特点。现场使用表明,样机采用感应加热、液压四向矫直和固定支点仿形打磨技术,自动化、专业化程度高,满足铁路标准规定的质量要求,提升了既有线维护质量和效率。 相似文献
24.
结合工程实例对气幕法沉井工艺有效减低井周土体扰动的原理,有利于减少沉井工程周边管线与构筑物搬迁,降低沉井工程的成本等优势及该工艺的应用进行分析和探讨,总结了一些经验,认为该工艺是在城市化地区沉井施工中一种值得采用的施工措施。 相似文献
25.
常莉蓉 《国防交通工程与技术》2010,8(4):67-70
重庆江北火车站大跨度钢管桁架无柱式雨棚,高14m,长540m,建筑面积达56230m2。结构工程跨度大,场地条件复杂,施工制约因素多,质量要求高。对主桁架等大型构件首次采用加工厂下料、现场加工制作、现场拼装、整体吊装的方案。详述了主桁架的吊装、焊接等工艺和施工控制措施。通过合理选择施工方案,严格按照工艺要求,合理安排施工程序,保证了工程如期保质保量的完成。 相似文献
26.
Development of Thermal Process and Numerical Modeling 总被引:2,自引:0,他引:2
Zhuang Liu Pan Zeng Department of Mechanical Engineering Tsinghua University Beijing P.R. China 《上海交通大学学报(英文版)》2000,(1)
IntroductionWithinrecentdecade,thenumericaIsimulationhasbeenrapidlyachievedandhasaPpliedtothermalmanufacturingprocess.ThephasetransformationiscomplicatedbythefactthatthereareseveralmicrostructuralscaIestoconsideHl1-I4].InordertorevealtheruIeofcomplexphasetransformation,itisnecessarytousethetoolofnumericalsimulationtomodelandcontroltheoverallprocessofphasetransformation.NowthecomputersimulationcangetsomereasonabIeresultSinmanyaspectsofthermalmanufacturingprocess:e.g.,thesimulationoftemperat… 相似文献
27.
WT. Wu J.P. Tang G. Li Scientific Forming Technologies Corporation Reed Road Columbus Ohio - U.S.A. 《上海交通大学学报(英文版)》2000,(1)
l.IntroductionThemostboortantdrivingforceinmanufacturillistoPrOduCeabetterPrOductatalowercost.GenerallyeffecthemethodsinchideshOrtenintheleadtiminthedesigncyCle,andredUcinthetoolingcostandmaChinedOWnmeatProductionst4e.AllOfthemrewtabettertmderstandingofhO… 相似文献
28.
Tiffany C. Smythe 《Coastal management》2013,41(6):665-680
Anecdotal evidence indicates that commercial and recreational water-dependent uses have been under development pressure in recent years, and in some cases have been converted to other uses. The conversion of water-dependent uses, which range from commercial shipyards to recreational marinas, may have many public costs, including the loss of access to public trust waters, the loss of jobs and associated economic activity, and the loss of traditional working waterfronts. This two-part study investigated the role of five coastal management programs in the northeastern United States in managing, monitoring, and protecting water-dependent uses. First, coastal managers in Massachusetts, Rhode Island, Connecticut, New York and New Jersey were interviewed to assess the conversion problem. Second, in collaboration with New York City-based Regional Plan Association, follow-up interviews were conducted with coastal managers and local planners in Connecticut, New York, and New Jersey to gain greater insight into the role of coastal management programs and local governments in managing and promoting water-dependent uses. This article presents select findings from this study and discusses recommendations for improving the capacity of coastal management programs and local governments to manage water-dependent uses for the benefit of the public. 相似文献
29.
分析客车底盘车架焊接结构,确定使客车底盘车架中段、前段、后段和行李舱骨架的变形量小的焊接工艺,使得整个底盘车架三段部分的焊接质量、形位精度满足设计和使用要求。 相似文献
30.