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241.
文章主要对汽车电子技术专业现代学徒制的概念进行了阐述,并提出汽车电子技术专业现代学徒制教学评价体系以及教学改革措施。 相似文献
242.
《铁道标准设计通讯》2017,(10):28-32
线路曲线半径是高速铁路主要技术标准之一,与高速铁路机车车辆运行时的舒适性、安全性及轮轨动力特性密切相关。运用多体动力学软件um建立高速铁路车线模型,考虑高速铁路轨道不平顺情况,研究曲线半径对列车运行时动力响应的影响。研究表明,随曲线半径的增加,横向加速度、脱轨系数、轮重减载率、磨耗功参数均呈现递减趋势,但半径超过7 000 m时递减趋势有所减弱,半径大于8 500 m时,各项指标趋向稳定。在满足安全性的条件下,为营造出优良舒适性,建议时速350/250 km共线高速铁路曲线半径取8 000 m,困难情况可取7 000 m。 相似文献
243.
首先分析自行式压路机总功率的计算方法.并根据压路机在实际工作中的功率谱和载荷谱提出了加权因子评价法;以国内外现有压路机的参数,建立功率回归计算的经验方程评价法及进行回归显著性检验。这两种评价计算方法为压路机的设计和发动机功率选择的合理性提供了依据。 相似文献
244.
This article, one part of the National Coastal Zone Management Effectiveness Study, evaluates the effectiveness of state coastal management programs in protecting estuaries and coastal wetlands. State programs were evaluated in a four-step, indicatorbased process to estimate (1) the relative importance of the issue; (2) the potential effectiveness of programs based on the policies, processes, and tools used; (3) outcome effectiveness based on on-the-ground indicators; and (4) overall performance, where outcome effectiveness was compared to issue importance and potential effectiveness. State evaluations were synthesized to provide a national perspective on CZM contributions and effectiveness in estuary and wetland protection. Although on-the-ground outcome data were sparse, they were sufficient to determine at least probable levels of effectiveness for about one-third of the states. Of these states, 80% were performing at expected or higher levels, considering how important the issue was in their state, and the scope and strength of the policies, processes, and tools they had deployed. Monitoring and record keeping, freshwater wetland management, and the use of nonregulatory restoration in coastal management were common program weaknesses. The evaluation approach and indicators used here are recommended as a starting point for designing a national monitoring and performance evaluation system addressing this CZM objective. 相似文献
245.
Marc J. Hershman James W. Good Tina Bernd-Cohen Robert F. Goodwin Virginia Lee Pam Pogue 《Coastal management》2013,41(2-3):113-138
The Coastal Zone Management Effectiveness Study was undertaken between 1995 and 1997 to determine how well state coastal management programs in the United States were implementing five of the core objectives of the U.S. Coastal Zone Management Act (CZMA). The five core objectives studied were: (1) protection of estuaries and coastal wetlands; (2) protection of beaches, dunes, bluffs and rocky shores; (3) provision of public access to the shore; (4) revitalization of urban waterfronts; and (5) accommodation of seaport development (as an illustration of the policy to give priority to coastal-dependent uses). Separate articles in this issue of Coastal Management report the findings of the five studies, each dealing with one of the core objectives. Each of the articles assesses issue importance, processes and tools used, and the limited outcome data available for that objective. This article provides an overview of the purposes of the study, the methodology used, the summary findings of each study, and overall conclusions and recommendations of the study team. State coastal programs are found to be effective in addressing the five CZMA objectives examined, but this conclusion is based on very limited information about program outcomes. A more definitive conclusion will require better outcome information. Coastal managers in the United States have not agreed upon indicators of success, which severely inhibits systematic and sustained collection of outcome information. A national outcome monitoring and performance evaluation system is recommended to address these deficiencies and allow better determinations of program effectiveness in the future. 相似文献
246.
Nicholas Falk 《Coastal management》2013,41(2-3):187-213
Abstract Technological innovations in the 1960s led to fundamental changes in the location and the nature of dock and warehousing work. Cities throughout the world have adopted very different planning and development approaches to facing these changes in technology. This paper draws mainly on a survey of the British experience in order to identify common problems and suggest some ways of solving them. The first part briefly analyzes the factors which have made docklands redundant in many areas. Problems and needs as seen by local officials are then reviewed; and some of the general difficulties facing efforts to reintegrate dock areas into the larger socioeconomic systems of a city are described. Then, the alternative policies of conservation and redevelopment are discussed. Finally, future policy directions are considered. 相似文献
247.
VC++在公路工程质量评定中的应用 总被引:1,自引:0,他引:1
介绍了在公路工程质量管理中,运用Visual VC++实现了公路工程质量检验评定系统的方法。其中包括数据存储、窗口界面、报表打印等主要功能的构成。讲述了窗口界面、数据存储、菜单、工具栏、数据输入窗口设计及报表打印的步骤。为施工管理人员和监理人员提供了质量检验评定管理平台,为计算机在公路工程质量管理的应用提供了范例。 相似文献
248.
249.
在参考现行公路养护状况评价方法的基础上,建立了一种新的公路技术状况评价方法,该方法针对不同设施特点分别设计了相应的评价单元段划分方法,根据设施的重要性和空间位置关系确定了新的设施层次关系,同时建立了一种既考虑设施重要性又考虑设施数量的新的加权方法即“等效长度加权法”,实现了单一设施评价和多设施综合评价的结合。并给出综合评价指标的计算方法和计算示例。 相似文献
250.
文章结合我国桥面防水层施工损伤试验实例,分析造成现场施工损伤的原因,介绍采用抗施工机械损伤性能、抗热集料刺破性能及不透水性能评价防水层的抗施工损伤性能的方法,提出相应的试验评价指标,对常见防水材料的抗施工损伤性能进行对比和评价,并确定了桥面防水层的最小厚度。 相似文献