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341.
Despite the emphasis placed on the contextual nature of integrated coastal management (ICM) implementation in the literature, many uniformities are encountered in ICM implementation worldwide. In this article the tangled threads of ICM practice are unravelled and a theoretically founded set of criteria for evaluating the design of ICM implementation models is provided. First, paradigms in integrated environmental management (IEM) implementation, the broader domain within which ICM practice is nested, are characterized in terms of their key concepts. Next, the paradigms are used as a mechanism to distill uniformities in ICM practice as reported in review articles. Finally a set of fourteen building blocks against which the scientific credibility of contextual, country-specific ICM implementation models can be validated, is generated by translating the theory-based characterization into evaluation criteria readily accessible to practitioners. 相似文献
342.
Within the scope of this article a nonlinear kinematics of the two-dimensional, non-shear-deformable and extensible Euler–Bernoulli beam imposed with the planar flexure and/or lengthening/shortening is considered. The complete and exact formulations of the pertinent kinematic response quantities (displacements, curvature and strain) are derived and discussed. Special emphasis is given to the case of the symmetric bending devoid of the external longitudinal force action, since it represents an appropriate idealization of the realistic load cases for the most of the ship and aircraft structures. The relationship between proposed and conventional formulations, i.e. those commonly accepted in the current structural engineering practice and employed by the current progressive collapse analysis methods based on Smith's approach, is discussed throughout the article and illustratively exemplified through the case of the pure symmetric bending of the Euler–Bernoulli cantilever. Finally, implications of the derived formulations pertinent to the progressive collapse analysis methods based on the Smith's approach are discussed. 相似文献
343.
Inconsistent choices in Stated Choice data;Use of the logit scaling approach to handle resulting variance increases 总被引:2,自引:0,他引:2
The scaling approach is a statistical estimation method that allows for differences in the amount of unexplained variation in different types of data, which can then be used together in the analysis. This approach has been mostly used in context of combining Stated Preference and Revealed Preference data, but has also been used as a method of identifying systematic differences in the variance of choices within a single Stated Preference data set, e.g. for investigation of learning and fatigue effects. This paper investigates whether a scaling approach is suitable for handling inconsistencies in Stated Choice data. Both the number of inconsistent choices, based on a test of violations of the transitivity axiom, and education are used as scaling variables. Scaling effects appear to exist due to inconsistent choices, and the amount of unexplained variance is shown to increase as the number of inconsistent choice increase. Scaling due to inconsistencies significantly improves the models and reduces the valuations of travel time. In addition, the scaling approach makes the valuations of travel time from the Stated Choice data more consistent with the valuations from Contingent Valuation data included in the same study. In spite of the fact that education is the only significant explanatory variable for the number of inconsistent choices, scaling due to education gives no significant improvement in the model. 相似文献
344.
澳门西湾大桥引桥上部结构设计 总被引:1,自引:0,他引:1
澳门西湾大桥主桥是世界上第一座双层承载的预应力混凝土斜拉桥,其南、北引桥总长1 425m,是60m跨度的预应力混凝土连续梁桥,着重介绍澳门西湾大桥引桥的上部结构设计。 相似文献
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347.
数控高频感应弯板成型设备曲板成型数据库系统开发研究 总被引:1,自引:1,他引:0
针对数控高频感应弯板加工工艺的特点和实际生产的具体要求,结合计算机技术和数据库技术,在探明弯板加工工艺的基础之上,前台运用面向对象的并运行于.NET Framework之上的高级程序设计语言C#语言,后台则采用MySQL 6.0建立数据库,开发了高频感应曲板成形设备的曲板成形数据库管理系统,实现从Tribon数据库中获得每一块加工的板的原始数据,记录并保存加工工艺参数数据,并且实现板的比较、形成数控指令、以及表格、文本及图形显示等功能,旨在收集和总结技术工人熟练的加工经验,快速确定出弯板加工的工艺参数,从而大大提高产品质量、效率和生产安全性. 相似文献
348.
该文通过对几个山区垃圾进场填埋场道路设计的实例分析,探讨山区垃圾填埋场进场道路设计中的重点和难点,特别是选线中的几个要点,总结其与一般道路设计的不同,最终在设计中找到安全、经济的设计方案. 相似文献
349.
高校公共篮球课参与式教学方法的应用研究 总被引:1,自引:0,他引:1
贾炜 《兰州交通大学学报》2011,(2)
本文以兰州交通大学体育课篮球项目选项学生为研究对象,运用文献资料法、访谈法、实验法和数理统计法,探求参与式教学方法在篮球课中的应用研究。通过参与式教学的实验研究表明,在公共篮球课教学中运用参与式教学能改变学生的被动学习状态,激发学生积极主动参加体育活动的学习兴趣和愿望,有效提高学生的身体素质、专项素质能力,发展学生的参与意识,提高参与能力,从而体现以学生为本的现代教育教学理念。 相似文献
350.