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随着Internet的发展和人们对各类信息需求的增加及企业面向社会提高知名度的需要,使得企业三维仿真WebGIS系统有着较为广泛的应用前景。文章探讨了利用VisualBasic等开发企业三维仿真webGIS系统的过程和方法。 相似文献
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爆炸装置搜索视景仿真训练系统的设计与实现 总被引:1,自引:0,他引:1
为解决搜爆人员在爆炸装置搜索训练过程中,真实训练环境搭建繁琐、人力与物资成本投入大等问题,在分析搜索爆炸装置训练过程的基础上,设计了一套爆炸装置搜索训练视景仿真系统。该系统通过搜爆场景逐级细化的方法构建虚拟场景,且以具有感应能力的三维模型模拟摩尔探测仪与非线性节点探测仪等搜爆工具。基于Open Scene Graph(OSG)图形开发库,以VC++为开发环境实现了爆炸装置搜索训练视景仿真。实践证明:该系统仿真度高,达到了爆炸装置搜索仿真训练的效果,并且运行流畅,沉浸感强。 相似文献
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Pernille Schiellerup 《Area》2008,40(2):163-171
An account is given of a research project with particular attention to the place of data analysis and interpretation. It shines some light into what often remains the black box of qualitative research practice, the mysterious process of generating a research narrative based on the data. The paper provides other apprentice researchers with an insight into what the data analytical experience can be like, warts and all. It raises issues to do with qualitative data analysis, the use of CAQDAS, grounded theory, the relationship between the narratives of the researcher and the researched, and about the training of qualitative researchers. 相似文献
125.
Design spectrum (DS) model is typically specified in a seismic code of practice for structural design. In a region of low-to-moderate seismicity where seismic code does not exist, a DS model in a well established code of practice is usually adopted, while the suitability of such model has seldom been evaluated. In this article, the elastic DS models for reference (rock) site stipulated in six major codes of practice (AS1170.4–2007, EN1998-1:2004, GB50011–2010, IBC–2012, NBCC–2010 and NZS1170.5:2004) have been compared and scrutinized. Three cities of low-to-moderate seismicity, namely, Melbourne (Australia), Hong Kong (China) and Karlsruhe (Germany), have been selected for illustrative purposes. Particular emphasis has been put on the parameterization scheme for DS model. It is found that huge discrepancies (over 100%) exist among the models, especially at the long period range, due to differences in spectral shapes and the recommended corner periods, which would lead to undesirable effects on the use of the displacement-based seismic design approach. It is urged that the values of corner periods should be determined specifically and cautiously based on the regional seismicity pattern and local geological conditions. 相似文献
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针对“微波遥感”教学中存在的学生动手能力差、实践能力培养欠缺等问题,探索利用开源软件进行实践教学辅助的教学改革。分析了开源软件在实验教学中的优缺点,介绍了微波遥感中常用的开源软件及主要功能。在此基础上,构建了一套开源软件辅助下的“微波遥感”实践教学项目,建立了标准实验数据集,编写了实验指导材料,并通过百度云盘等方式实现了网络共享。通过教学改革,拓展了学生的实践教学途径,提高了学生的实践动手能力及微波遥感数据处理能力。 相似文献
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水准测量一直是获得地面点精密高差的重要手段,其测量速度慢、效率低也一直是困扰全球测量界的一大难题。为了提高水准测量的速度和效率,本文提出了新一代高速对向观测数字水准尺仪的概念、结构、原理与方法。具体采用水准仪与标尺合二为一的一体化结构设计,将传统水准测量的3点互动配置改变为2点互动配置来提高测站仪器安置速度和地形适应能力;采用对偶测量原理将传统水准测量的单向单系统测量改变为对(双)向双系统测量来提高水准测量的精度及可靠性;采用正交二脚架及L型水准器来提高水准标尺及水准仪的安平速度。理论分析及初步实践表明:新一代高速对向观测数字水准尺仪与传统水准仪相比,水准测量效率可提高1倍以上,是目前世界上最快速、最智能、最精密的电子水准测量系统。高速对向观测数字水准尺仪的发明,将对全球大地及工程测量界产生重大及颠覆性的影响,将开启人类社会普及电子水准仪的新时代。 相似文献
130.
Sirpa Tani Kalle Juuti Seija Kairavuori 《Norsk geografisk tidsskrift. Norwegian journal of geography》2013,67(3):172-178
The article investigates the potential and challenges of integrating geography with other school subjects. The analysis is based on the outcomes of a course that introduced the principles of discipline-based integration. The course was included in multicultural-class teacher education programme at the University of Helsinki. For a project within the course, the students worked in small groups and made short films that integrated three subjects – geography, physics, and visual arts – in order to evoke questions of space in children's minds. The students were asked to write essays in which they analysed their understanding of space from the three subjects’ viewpoints, describe the aims and contents of their short films, and lastly reflect on their experiences of the potential and possible problems in discipline integration. In this article, the authors analyse the students’ experience of the integration between the geography, physics, and visual arts. In general, the students experienced discipline-based integration as an interesting way of working. Moreover, the project seemed to deepen their understanding of different grounds for integrative pedagogy. Although the students reported some difficulties regarding the subject knowledge required for fruitful integration, the process enabled them to construct a better understanding of the identity of each discipline. 相似文献