在教育部倡导信息技术与高等教育实验教学深度融合的背景下,以隧道施工工艺虚拟仿真实验教学项目为研究对象,在分析隧道施工方法的基础上,对虚拟仿真实验教学系统的架构和功能进行了探讨,运用网络开发技术搭建了虚拟仿真实验平台,采用Unity 3D引擎与MySQL数据库对隧道施工工艺流程进行了开发,实现了隧道中隔壁法施工全过程,并利用仿真动画技术研制了隧道多种施工方法动画流程视频,为学生提供了丰富的实验教学内容,取得良好的实验教学效果.

通过对拱桥结构的分析,利用Bentley建模平台Microstation以及结构详细模型软件Prostructures,探讨建立桥梁三维模型的方法,构建下承式简支拱桥的系梁、主拱、吊杆、预应力钢束等构件的BIM模型,并对桥梁整体进行组装;对预应力钢束和普通钢筋进行碰撞检查,及时发现图纸存在的问题,避免返工;利用LumenRT软件平台,实现桥梁整体模型动态漫游以及场景的实时交互,为该类桥梁结构的快速建模和三维可视化提供新的思路.

简述了BIM的含义和特点,分析了BIM技术在桥梁工程中的应用优势,利用Autodesk Revit软件,对桥梁结构进行了三维仿真模拟,并在Navisworks软件分析平台下模拟了施工过程,为该类桥梁结构提供三维可视化模型和4D施工过程模拟的新展示理念.

The meaning and characteristics of BIM technology are summarized briefly.The model of PC continuous box-girder bridge stiffened by steel truss is established with Autodesk Revit software platform based on parameterized libraries of bridge pier, box girder and reinforcement.The library models can be modified automatically.The graphics format conversion of the BIM model is discussed and the dynamic roaming demonstration is implemented based on Lumion software platform, which provides 3D visualization and new ideas for detailed demonstration of such complex bridge structures.

针对普铁综合图绘制系统无法实现高铁双线并行综合图的绘制问题,提出了高铁综合图自动生成和输出的方法.通过在Auto LISP中使用ActiveX对象与Microsoft Excel对象,实现了Excel数据文件的导入和数据转换;基于高铁综合图信息,以Visual LISP语言实现了高铁综合图的自动生成;采用图形裁剪算法,实现了长条形综合图的自动分幅;运用虚拟打印技术,实现了分幅图的批量打印或PDF文件生成.实验结果表明:所提方法不仅可以快速高效地进行数据处理和综合图自动生成,还能准确地进行图形自动分幅和输出.研究结果对铁路基础设施、综合维修、列车运行等方面的信息化研究具有重要的参考价值.

工程图学系列课程属于量大面广的技术基础课,该课程的教学改革对后续课程的学习有着直接的影响,是一个需要长期摸索、不断提高的过程.本文结合教育部出台的“卓越计划”对人才培养的要求,本着提高学生学习主动性与自觉性的原则,对工程图学系列课程的课程体系、教学方法和考核方式进行了一系列改革,制定了基于模块化教学的课程教学体系和基于过程评价的考核体系,并经历了两年的实践检验,效果良好.

为评价某公铁两用斜拉桥桥面系的承载能力,利用ANSYS建立了有限元模型,分析该桥面系在最不利荷载工况下的整体受力和各构件的位移及最大应力分布状况,指出该斜拉桥桥面系的承载力及各构件的强度均满足规范要求.

本文以伊犁地区146个草地样地调查数据为基础，结合遥感及气象数据，进行草地植被地上生物量与 NDVI、EVI、海拔、年均降水、年均气温、积温、干燥度、湿润指数等因子的回归分析。并通过各因子对地上生物量影响权重参数分析和加权融合，运用 ArcGIS 软件，反演分析了新疆伊犁地区草地植被地上生物量的空间分布特征。结果表明，新疆伊犁地区草地平均产草量约为704．96 kg／hm2，与20世纪80年代全国草地调查数据相比，产草量有所下降。草地植被地上生物量与各项因子具有较好的相关性，反演结果与伊犁地区的地形、地貌、气候特征基本吻合，反映了伊犁地区草地植被的空间分布特征。地上生物量反演结果得到验证，预测值与实测值之间相关系数（R 2）为0．8532；均方根误差（RMSE）为216．559 kg／hm2，偏离度为22．92％，可以为新疆伊犁地区草地资源合理利用与评价提供参考。

Three-dimensional entity model is foundation for the building of 3D visualization information system. Through the research on the basic theory and method about geometric modeling and graphic processing, the paper discusses three-dimensional graphics interface and solid modeling method in ObjectARX tool which are based on the theory of constructive solid geometry. It realizes the three-dimensional solid automatic modeling, graphics transformations and Boolean operations with Visual C++ and ObjectARX tool for secondary development. Bridge structure is taken as an example of parametric modeling. It is the basis of the construction of bridge Information platform.

在对桥梁结构特征、模型变量与建模过程进行分析的基础上,总结了各种结构的建模规律,提出适合不同结构的建模方法及建模中注意的问题;利用VC++和ObjectARX工具,通过创建图形实体及其面域,形成建模参数,运用AcDb3dSolid类建立的对象容器,实现了三维实体的拉伸、扫掠和放样参数化建模,并对立体添加颜色或材质;运用图形变换和布尔运算,对三维实体进行整体组装,实现了桥梁结构三维实体参数化建模.

With Visual Lisp as development tool in AutoCAD environment, this paper studies data processing, graphics rendering, graph cutting and printing, and develops a fast and highly effective automatic drawing software to fulfill data importing, graphics rendering, graphic framing and batch printing in order that the efficiency of drawing is improved and a graphic platform is provided for railway track maintenance department.

Optimal location and site distribution rationality evaluation of the 120 Emergency Centers are of great significance to the formulation of emergency treatment plan and rational allocation of urban public service facilities. Taking Chengguan District of Lanzhou City as the research area, this paper employs GIS spatial analysis method and the software ARCGIS to carry out buffer analysis and overlay analysis of the main medical sites and the main line of the Chengguan District, and thus to get service coverage areas. The medical emergency service coverage and service level classification map of the Chengguan District of Lanzhou City can be got by grading the coverage areas according to the classification requirement, visually displaying the service level of every area. The results show that medical emergency site distribution of Chengguan District is too concentrated, basically concentrated in urban center, site distribution is not reasonable enough, and there are a lot of overlapping areas and a certain blind zone of service.

Aiming at the emerging issues within the teaching process of visual programming, the corresponding improved teaching methods is put forward. Based on the MFC framework, the students are guided to learn OpenGL toolkit of visualization functions according to strengthening practices, improving multimedia teaching, inducing examples and producing teaching demonstration program. Combined with training methods of GIS major, the study and practice platform is developed for students, and the teaching demonstration system is obtained to aid the classroom teaching. It is significantly improved the quality teaching that the students′ thinking patterns extended by using interactive teaching methods.

According to the thought of incremental inserting algorithm , this paper establishes the three-dimensional point , tri-angle and dynamic array to build TIN data model , programs to achieve the incremental inserting algorithm based on OpenGL In VC++ 6 . 0 software development platform , and completes the functions to display TIN model and query information .

On the basis of the structural characteristics of various kinds of steel truss bridge and member models, interface functions of drawing environment settings for setting layer, color, line type, text and marking style are established, and the interface services to draw graphics, mark dimensions and write characters are developed. According to the different parameters of steel truss members, parametric drawing and symbol annotation sub-module for various members are created, parametric drawing for members of steel truss bridge is fulfilled, and then new concept and method for parametric drawing of steel truss bridge are proposed.

To improve the efficiency of area filling, the paper makes an introduction and analysis for the three common area filling algorithms and further improves the active-edge-table algorithm which has more obvious advantages compared with the others. For the deficiency of traditional algorithm, the improved algorithm makes full use of vertex information and establishes the dynamic discovery mechanism of active edges, making the time efficiency and space efficiency both improved;meanwhile, in order to fill the self-intersected polygons, an easy and effective method to detect self-intersected vertices based on scan line is proposed, making the adaptability of the algorithm enhanced. Experimental results demon-strate that the improved algorithm achieves very good results.

Establishment of campus buildings visualization query system is important campus information management modernization of scientific means.Combining with building visualization query system subject,three-dimensional modeling in AutoCAD and 3DMAX is built and two-dimensional and three-dimensional map in ArcGIS is produced by using ArcGIS Engine as the system development components and C# for the second development to realize browsing buildings,editing graphics,modifying the attributes and querying functions in two-dimensional and three-dimensional view on campus.The platform is provided for the school function departments to query information,plan campus and manage real estate.

在构建河系树的基础上,结合河流层次、等级、数量密度和长度等河流描述因子,提出将河流选取数量按河流数量密度逐级分摊到河系与河系内部各级子流域的方法。选取的河流按其层次逐层输出可视化的试验表明,该方法是有效的。

The engineering graphics course is a specialized basic course required of the students in Colleges of engineering,is one of the important basic courses in engineering colleges to realize the goal of cultivating talents.The reform of the course will directly affect the training plan implementation and follow-up course,should be carefully.The task group on the basis of a careful reading of some opinions of the Ministry of education on the implementation oftraining planexcellent engineer education,combined with thebasic requirementsEngineering Drawing Course Teaching in Colleges and universities,has conducted the research and the reform practice of a series of science course in our college of engineering drawing teaching system,teaching content,teaching means,examination methods,to explore a set of not only conforms to the modern education idea,but also embodies the value of traditional teaching,to cultivate and improve students' ability of engineering design teaching mode.

本文以NOAA-18(N)AVHRR/3数据,运用通用劈窗技术获得地表温度.首先,利用MODTRAN 4模拟不同地表和大气状况下热红外通道(Ch4,10.3～11.3μm和Ch5,11.5～12.5μm)的星上亮温,并建立模拟数据库.其次,按照地表温度、大气可降水汽含量、地表比辐射率和观测天顶角,对模拟数据库分组,确定出各分组的通用劈窗算法系数.然后,将构建的地表温度反演模型应用到NOAA-18(N)AVHRR/3数据,模型所需的地表比辐射率由NDVI阈值法确定,大气可降水汽含量是利用Li等(2003)提出的一种劈窗的协方差与方差比的方法来估算.反演结果表明:在观测天顶角小于30°或者大气可降水汽含量小于3.5 g/cm2时,地表温度反演的均方根误差小于1.0K;在观测天顶角小于45°并且大气可降水汽含量小于5.5g/cm2情况下,均方根误差小于1.5K.最后,利用美国通量站的实测数据对地表温度反演结果进行了验证,结果表明均方根误差小于1.8K.