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排序方式: 共有349条查询结果,搜索用时 15 毫秒
151.
152.
基于地理设计的三维道路设计系统研究与实现 总被引:2,自引:0,他引:2
道路规划设计是一项复杂的系统工程,现阶段道路设计采用传统的平台难以适应空间分析、三维展现、交互设计等新的需求,更不能充分利用GIS分析、参数化设计等新技术为设计服务。地理设计的诞生为将设计与分析的融合提供了指导思想,参数化设计则为基于规则的道路设计提供技术基础。本文以地理设计为指导、以参数化驱动设计为手段,构建一个基于三维地理环境的道路设计系统,阐述地理设计、参数化驱动设计在系统中的作用及系统的结构组成,最后展现系统建设成果。 相似文献
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根据某高速公路南店村大桥地基因淤泥质土含水量大于30%而承载力低的实际情况,采用石灰粉喷桩,加固处理南店村大桥桥台软基。根据开挖与动测结果,满足桥台地基承载力不小于150kPa的要求。该方法具有设备简单、施工方便、经济效益好的特点。 相似文献
156.
Within a shipyard, many designers each have their own design objective cooperating in complex design circumstance that a variety of software tools run on different hardware platforms. Different CAD systems are used by different design stages and departments, and the design result is usually delivered on paper drawings. The proliferation of data and the rising number of disparate data systems do not communicate with each other and certainly do not collaborate. Advanced 3D modelling tools are installed in most of progressive shipyards for advantage to improve their productivities. However these 3D models are repetitiously constructed as per the specified design objectives of disparate software tools in various design stages. This paper describes the development of collaboration modelling framework, knowledge-based design support system, to make a web-based data-sharing collaborative environment potentially allowing to facilitate some applications, construct 3D lines rapidly, translate the product data, and further be capable of providing reasonable model configurations for XML type, and sharing the web services from the Internet to comply with shipyards’ specific strategy for each particular case to be designed. 相似文献
157.
ISD单片语音录/放器件及电路设计 总被引:1,自引:0,他引:1
ISD单片语音器件的独特之处,是有用直接模拟存储技术,语音信号以其原本的模拟形式直接存入模拟量存储器中并长远保存。省去了传统的A/D和D/A数模转换机制,能高保真的将语音内容再生。这是一种高新录/放技术。另外,给出的ISD基本录/放电路十分简单易用。可方便地为微机系统、测控仪表、电器和广播等设备所采用,使设备具有高效功能。 相似文献
158.
On February 6, 1994, a large debris flow developed because of intense rains in a 800-m-high mountain range called Serra do Cubatão, the local name for the Serra do Mar, located along the coast of the state of São Paulo, Brazil. It affected the Presidente Bernardes Refinery, owned by Petrobrás, in Cubatão. The damages amounted to about US $40 million because of the muck cleaning, repairs, and 3-week interruption of the operations. This prompted Petrobrás to conduct studies, carried out by the authors, to develop protection works, which were done at a cost of approximately US $12 million. The paper describes the studies conducted on debris flow mechanics. A new criteria to define rainfall intensities that trigger debris flows is presented, as well as a correlation of slipped area with soil porosity and rain intensity. Also presented are (a) an actual grain size distribution of a deposited material, determined by laboratory and a large-scale field test, and (b) the size distribution of large boulders along the river bed. Based on theory, empirical experience and back-analysis of the events, the main parameters as the front velocity, the peak discharge and the volume of the transported sediments were determined in a rational basis for the design of the protection works. Finally, the paper describes the set of the protection works built, emphasizing their concept and function. They also included some low-cost innovative works. 相似文献
159.
《Marine Policy》2016
Ecosystem management (EM) requires new tools to facilitate stakeholder access to information and analysis, however these tools are often not perceived by stakeholders to be usable, useful, and salient to their concerns. This paper provides a case study which applies new participatory design methods, known as design thinking, to create an EM tool called the Great Lakes Aquatic Habitat Explorer. Both participating and non-participating stakeholders rated the usability of the resulting tool positively, and stakeholders who attended design workshops rated the perceived usefulness and salience of the resulting tool more highly than those who had not. Design workshop survey data found that the methods produced an environment of collaborative learning among participants, including diverse participants, authentic dialog, and creativity. Design thinking methods hold promise for the development of new tools which better respond to the needs of EM stakeholders. 相似文献
160.
根据福建元洪港无长期海浪和风观测资料及该水域的多岛礁地形的特征,以邻近的平潭海洋站30a实测海浪资料,采用考虑底摩擦效应的浅水波浪折射数值模式进行港区设计波高计算,并与港工程规范算法相比较,得出码头,航道口门和航道中段的设计波高参数。 相似文献