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1.
GIS专业的学生需要一定的软件设计和编程技能,传统单一的课堂教学模式难以适应当前培养GIS人才的要求。文中提出通过引导学生参加软件考试,结合考试类型和考试科目进行考试的技术指导和培训,并将其引入到"空间数据库"的课堂教学,使得课程教学与软件考试紧密结合;通过引入任务驱动、情景教学、分级和分组的教学方法,以及课程考试和软件考试的双重考核方法,促进"空间数据库"课程教学改革。课程改革的实施不仅活跃了课堂教学氛围,改善课堂秩序,而且促进学生课后的学习自主性和社会实践积极性,为培养高质量的GIS人才打下基础。  相似文献   
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目的】为分析铜仁区域短时强降水极端阈值及分布特征。【方法】利用铜仁区域内10个国家级台站2006—2022年3—11月逐日逐时降水资料,分别挑选1 h、2 h、3 h降水极值和次极值进行升序排列,基于第95个百分位的基本方法综合判定阈值,通过常规统计结果判定其分布特征。【结果】1 h降水量≥25 mm、2 h降水量≥40 mm、3 h降水量≥50 mm均可作为铜仁区域短时强降水的阈值。松桃是铜仁市短时强降水的高值中心,江口为次中心。西部5县和东部的万山6月份为短时强降水高发月份;东部松桃、碧江、玉屏7月为高发月份,江口以8月为主。铜仁区域短时强降水主要集中在5—8月,占总日数的84.4%,且67.3%的短时强降水以单站形式出现,短时强降水的局地性明显。铜仁发生短时强降水以夜间为主,江口最为明显,短时强降水夜间频数与短时强降水总频数之比达到84.9%,夜间短时强降水量与短时强降水总量之比达到86.5%,短时强降水较降水总量的夜雨性更为明显。【结论】该研究对深入了解铜仁区域短时强降水作了有益的探索,对科学制定强降水“三个叫应”指标和防灾减灾具有一定的指导意义。  相似文献   
3.
针对传统的建筑物建模方法需要大量人机交互操作,建模过程复杂和成本高的问题,该文提出一种参数化建筑物三维建模方法。首先,以高分辨率遥感影像和建筑物立面影像作为数据源,在遥感和GIS软件平台的支持下,提取建筑物的底面边界、高度、楼层数、层高和屋顶类型等空间数据和属性数据,并将其保存至GIS空间数据库。其次,提出基于拉伸、拆分、添加结构面过程的建筑物主体结构建模方案,并设计了模型自动生成算法。进一步,采用Ruby面向对象语言,通过调用SketchUp平台的应用程序接口函数,结合编程实现了建筑物的自动化建模。最后,开发了建筑物参数化建模插件。实际建模实验成果表明:该方法能够显著降低建模人员劳动强度,提高建模效率。  相似文献   
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In addition to the normal service loadings, engineering structures may be subjected to occasional loadings such as earthquakes, which may cause severe destruction. When the steel rebar is corroded, the damage could be more serious. To investigate the seismic performance of corroded RC columns, a three-dimensional mesoscale finite element model was established. In this approach, concrete was considered as a three-phase composite composed of aggregate, mortar matrix and interfacial transition zone (ITZ). The nonlinear spring were used to describe the bond slip between steel and concrete. The degradation of the material properties of the steel rebar and cover concrete as well as the bonding performance due to corrosion were taken into account. The rationality of the developed numerical analysis model was verified by the good agreement between the numerical results and the available experimental observation. On this basis, the effect of corrosion level, axial force ratio and shear-span ratio on the seismic performance of corroded RC columns, including lateral bearing capacity, ductility, and energy consumption, were explored and discussed. The simulation results indicate that the mesoscopic method can consider the heterogeneity of concrete, to more realistically and reasonably reflect the destruction process of structures.

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6.
全面介绍了现代信息高速公路中的各种数据接入技术及其发展状况,并对我院校园网数据接入提出了一些设想。  相似文献   
7.
According to the characteristics of Chinese marginal seas, the Marginal Sea Model of China (MSMC) has been developed independently in China. Because the model requires long simulation time, as a routine forecasting model, the parallelism of MSMC becomes necessary to be introduced to improve the performance of it. However, some methods used in MSMC, such as Successive Over Relaxation (SOR) algorithm, are not suitable for parallelism. In this paper, methods are developedto solve the parallel problem of the SOR algorithm following the steps as below. First, based on a 3D computing grid system, an automatic data partition method is implemented to dynamically divide the computing grid according to computing resources. Next, based on the characteristics of the numerical forecasting model, a parallel method is designed to solve the parallel problem of the SOR algorithm. Lastly, a communication optimization method is provided to avoid the cost of communication. In the communication optimization method, the non-blocking communication of Message Passing Interface (MPI) is used to implement the parallelism of MSMC with complex physical equations, and the process of communication is overlapped with the computations for improving the performance of parallel MSMC. The experiments show that the parallel MSMC runs 97.2 times faster than the serial MSMC, and root mean square error between the parallel MSMC and the serial MSMC is less than 0.01 for a 30-day simulation (172800 time steps), which meets the requirements of timeliness and accuracy for numerical ocean forecasting products.  相似文献   
8.
针对矿区基准点布设时间较早,容易发生位移的特点,为确保高精度GPS控制网坐标系统转换后的质量,克服基准点位移对转换成果的影响,提出顾及基准点位移的高崩溃污染率抗差估计理论,建立坐标转换参数的估计模型和转换后GPS网的质量评价体系.以兖州某矿区为例进行分析,结果表明,该模型可以选择分布合理且稳定的基准点,很好地保留了GP...  相似文献   
9.
针对三维地质建模工作繁琐、复杂,从手工绘制地质模型角度提出了一种基于GIS耦合SketchUp技术的三维地层模型绘制方法。采用钻孔资料作为数据源,通过ArcGIS的插值和栅格转换工具生成地层三角网格。然后利用SketchUp的封面插件和表面求交工具,生成地层的三维体模型。该方法操作简单、直观和易于掌握,具有一定的推广和应用价值。  相似文献   
10.
矿体建模是矿山可视化的重要内容之一。在矿体建模过程中,模型编辑是建模的关键环节。本文从软件开发的角度,探讨了三维矿体线框模型编辑器的设计与开发方法。介绍了开发环境、建模方法、空间数据模型以及模型编辑等关键技术,并重点讨论了人机交互编辑的具体实现过程。该编辑器已经能够在三维可视化环境中交互绘制矿体剖面轮廓线,并通过轮廓线快速地构造矿体的线框模型。最后以矿体断面图为实例验证了该编辑器的有效性和易操作性。  相似文献   
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