基于GIS与Scoops 3D的水动力型滑坡区域稳定性分析

库岸边坡在库水位变动、降雨等水动力因素的作用下易发生水动力型滑坡,进而威胁库区居民生命及财产安全。以某流域HD和DHQ库段为主要研究区段,在对已有滑坡点进行地质调查和遥感解译的基础上,将ArcGIS的空间分析与三维斜坡稳定性分析模型(Scoops 3D)相结合,对研究区段的潜在滑面进行系统的三维搜索及识别,并基于GIS数据与室内试验等确定计算参数,对天然和暴雨两种工况下的区域滑坡稳定性进行评价比较。结果表明:(1)研究区历史滑坡点分布与基础地质环境、岩土体强度指标参数有很强的相关性;(2)天然工况下,非稳定区主要分布在DHQ坝区、迤场、DH坝址、拉巴铁、宝塔河以及甸尾附近;(3)暴雨工况下,非稳定区面积较天然工况有显著的增大,DHQ坝址、营盘镇、甸尾、HD坝址附近有较为密集的分布;(4)暴雨工况下模型计算的非稳定区与历史滑坡点的分布特征基本一致。由此可见,三维斜坡稳定性分析模型可以较为准确模拟不同工况下滑坡稳定性,且易发程度区分明显,稳定性评价结果在一定程度上反映了研究区段的稳定性时空分布。

具身认知视域下利用3D GIS技术赋能高中地理教学的实践探究——以“地貌的观察”为例

在教育数字化转型背景下,借助地理信息技术提升学生的地理空间能力和地理实践力,成为地理学科教学的重要趋势。针对传统地理课堂教学中地理实践力培养落实难,野外观察存在经济成本高、安全隐患、难以观察全貌等问题,3D GIS技术为地理课堂教学提供了具身的教学方法和手段。本文从具身认知理论出发,阐明3D GIS技术赋能“地貌的观察”适切性的基础上,在案例设计中具体说明3D GIS技术开发教学资源的步骤及在地理课堂教学中的应用,为地理实践力的落实以及师生地理信息素养的提升提供参考。

特高压GIS隔离开关开合母线方式3试验中暂态电压波形解析

为分析特高压GIS隔离开关方式3试验中暂态电压与断口间动态绝缘特性的关联,文中构建了超宽频暂态电压监测系统和电弧形态观测系统,全过程监测了特高压GIS隔离开关开合过程中电源和负载侧的暂态电压,以及动静触头间击穿时的电弧形态。试验发现,隔离开关方式3试验合闸和分闸过程中电弧重燃和熄灭交替出现的持续时间分别为140 ms和240 ms。电压峰值附近发生的电弧熄灭,将引发过电压,但幅值低于1.4 p.u.。分合闸过程中产生的暂态电压持续时间约12μs,波头时间约25 ns,其频率主要分布在1 MHz以下,最高瞬时频率接近50 MHz。方式3试验中,断口间击穿不会产生特快速暂态过电压,与方式1存在较大区别。文中研究揭示了隔离开关分合闸过程中暂态电压的激发机理和时频特征,以及对断口间动态绝缘的影响,为GIS隔离开关的性能考核和优化设计提供了有力支撑。

基于GIS和SWMM的城市雨洪模型构建与业务化

近年城市化进程加快,极端天气频繁出现,各大城市都出现过严重的内涝情况,严重危害人民群众的财产和人身安全。暴雨洪水管理模型(storm water management model,SWMM)等常用的城市雨洪径流模型已在城市内涝研究中广泛应用且效果显著。但构建SWMM工程文件所需的数据处理相对烦琐且对大多数模型来说,模型的输入和输出数据不直观,使用极不便。针对这一现状,研究如何快速构建城市雨洪模型并实现业务化意义重大。以成都市双流区东升街道为例,基于双流行政区划边界图层、排水(雨水)管网分布图、气象站点实况监测、数字高程模型(digital elevation model,DEM)和土地利用分类等多源数据,利用地理信息系统(geographic information system,GIS)技术,数字化并概化双流区的地下管网,利用水文分析法和泰森多边形法划分东升街道子汇水区,使用表面分析方法和分区统计方法计算处理各子汇水区的不透水占比、平均百分比坡度;利用GIS软件开发技术实现子汇水区特征宽度的求取;最后实现成都市双流区东升街道雨洪模型的程序化构建、自动化运行和结果可视化等一系列业务化研发,并利用历史内涝个例数据对构建的东升街道雨洪模型进行模拟对比验证,结果显示溢流节点与记录发生的汛情一致,效果良好;相应成果也应用到了双流城市内涝预警业务中。

BIM+GIS技术在城市建筑三维可视化中的应用研究

本文以某工程为例,采用几何转化和渲染处理相结合的方式,得到了BIM轻量化模型。将轻量化模型导入三维可视化展示平台,按照构件对应的空间标高属性信息,通过触发系统BIM模型的层高属性,实现了BIM模型分层、分类展示;运用3GIS技术,结合对应关联、地物类对应关联、混合关联等的处理方式,将地理信息中的属性数据与矢量化或栅格数据相结合,形成了一套能够应用的GIS地理数据。在城市空间直观可视的基础上,整合城市建设数据,形成城市建设基础数据库,为打造“城市可视、管理精细、资源共享、数据开放、服务便捷”的智慧城市建设与运维管理的新体系奠定数据支撑。

BIM-GIS技术在输水隧洞工程勘察设计中的应用

为促进BIM和GIS技术在输水隧洞工程勘察设计中的应用,针对BIM与GIS数据存在数据来源多样化、融合标准化程度低等问题,以3D Tiles格式为数据集成容器,提出了通过格式转换、坐标转换、属性集成、轻量化等步骤实现BIM与GIS融合的技术路线。以罗田水库—铁岗水库输水隧洞工程为例,验证了该方法的实用性和可操作性,并探讨了基于3DE的BIM模型和GIS多源数据融合成果在输水隧洞工程勘察设计阶段中的应用。研究成果可为同类输水隧洞工程提供参考。

基于BIM与3D GIS的大学数字校园系统设计与研究

作为建筑行业的发展方向,建筑信息模型(Building Information Modeling,BIM)技术已然成为实现建筑信息化发展目标的关键技术。在数字校园建设过程中,若能够将地理信息系统与建筑信息模型相融合,则可实现校园全场景的三维可视化与建筑设施精细化管理。从场景搭建、数字校园建模以及BIM与三维地理信息系统(3D Geographic Information System,3D GIS)结合应用角度出发,阐述了大学数字校园系统设计要点,为数字化校园持续发展奠定基础。

基于3D GIS的突发化学事故危害评估与救援辅助决策支持系统

化学事故具有突发性强、环境污染破坏严重、救援难度大等特点,对突发化学事故的影响范围、破坏程度进行快速评估,为事故抢险救援提供决策支持,是应对重特大突发化学事故、降低事故损失的重要手段。本文基于三维地理信息系统(Three-dimensional Geographic Information System,3D GIS),在充分考虑下垫面影响的前提下,研究了大气污染扩散模型,提出了扩散场快速构建技术及兼顾污染分区的救援力量调度方法,并以此为核心建立了系统总体框架,形成了集扩散模拟、危害分析、救援调度等功能于一体的突发化学事故危害评估与救援辅助决策支持系统,可为突发化学事故危害后果评估与辅助救援决策提供有效的技术支撑。

Lie symmetry analysis and invariant solutions for the(3+1)-dimensional Virasoro integrable model

Lie symmetry analysis is applied to a(3+1)-dimensional Virasoro integrable model and the corresponding similarity reduction equations are obtained with the different infinitesimal generators.Invariant solutions with arbitrary functions for the(3+1)-dimensional Virasoro integrable model,including the interaction solution between a kink and a soliton,the lump-type solution and periodic solutions,have been studied analytically and graphically.

Interaction solutions for the second extended(3+1)-dimensional Jimbo–Miwa equation

Based on the Hirota bilinear method,the second extended(3+1)-dimensional Jimbo–Miwa equation is established.By Maple symbolic calculation,lump and lump-kink soliton solutions are obtained.The interaction solutions between the lump and multi-kink soliton,and the interaction between the lump and triangular periodic soliton are derived by combining a multi-exponential function or trigonometric sine and cosine functions with quadratic functions.Furthermore,periodiclump wave solution is derived via the ansatz including hyperbolic and trigonometric functions.Finally,3D plots,2D curves,density plots,and contour plots with particular choices of the suitable parameters are depicted to illustrate the dynamical features of these solutions.

论三维GIS及Unity 3D技术管理的可视化构建

以三维GIS及Unity 3D技术为支持,分析了高速公路施工进度管理系统的功能及需求,认为在三维动态建模、动态分段、场景化和可视化等模块及计算工程量的模型构建中,Unity 3D和GIS技术加持下的综合应用能够极大提升可视化效果,解决高速公路工程关键性的技术难题。

基于BIM+3D GIS的智慧地下管线系统

为了城市地下管线的可持续发展,要解决传统市政管线管理模式中存在的信息不透明、管理难度大等问题,以实现三维可视化、管线状态监测及视频监控、故障定位等目标。从系统总体架构和系统功能、数据库建设等方面出发,整合应用建筑信息模型(building information modeling,BIM)技术与三维地理信息系统(three-dimensional geographic information system,3D GIS)技术,提出智慧地下管线系统的建设方案。结合工程实例,应用智慧地下管线系统,分析与评价其应用效果。以期为未来地下管线的巡查、分析、决策提供数据支持,为相关工程提供借鉴。

Evaluation of Airway Obstruction at Soft Palate Level in Male Patients with Obstructive Sleep Apnea/Hypopnea Syndrome:Dynamic 3-Dimensional CT Imaging of Upper Airway

This study examined the dynamic characteristics of upper airway collapse at soft palate level in patients with obstructive sleep apnea/hypopnea syndrome（OSAHS） by using dynamic 3-Dimensional（3-D） CT imaging.A total of 41 male patients who presented with 2 of the following symptoms,i.e.,daytime sleepiness and fatigue,frequent snoring,and apnea with witness,were diagnosed as having OSAHS.They underwent full-night polysomnography and then dynamic 3-D CT imaging of the upper airway during quiet breathing and in Muller＇s maneuver.The soft palate length（SPL）,the minimal cross-sectional area of the retropalatal region（mXSA-RP）,and the vertical distance from the hard palate to the upper posterior part of the hyoid（hhL） were compared between the two breathing states.These parameters,together with hard palate length（HPL）,were also compared between mild/moderate and severe OSAHS groups.Association of these parameters with the severity of OSAHS [as reflected by apnea hypopnea index（AHI） and the lowest saturation of blood oxygen（LSaO2）] was examined.The results showed that 31 patients had severe OSAHS,and 10 mild/moderate OSAHS.All the patients had airway obstruction at soft palate level.mXSA-RP was significantly decreased and SPL remarkably increased during Muller＇s maneuver as compared with the quiet breathing state.There were no significant differences in these airway parameters（except the position of the hyoid bone） between severe and mild/moderate OSAHS groups.And no significant correlation between these airway parameters and the severity of OSAHS was found.The position of hyoid was lower in the severe OSAHS group than in the mild/moderate OSAHS group.The patients in group with body mass index（BMI）≥26 had higher collapse ratio of mXSA-RP,greater neck circumference and smaller mXSA-RP in the Muller＇s maneuver than those in group with BMI26（P0.05 for all）.It was concluded that dynamic 3-D CT imaging could dynamically show the upper airway changes at soft palate level in OSAHS patients.All the OSAHS patients had airway obstruction of various degrees at soft palate level.But no correlation was observed between the airway change at soft palate level and the severity of OSAHS.The patients in group with BMI≥26 were more likely to develop airway obstruction at soft palate level than those with BMI26.

基于BIM+3D GIS的智慧城市管理平台

随着我国城市化进程的加快,传统的治理方式与质量与城市运营发展的要求越来越不相适应。本文研究了基于BIM+3D GIS的智慧城市管理方法,构建了基于BIM+3D GIS的智慧城市管理平台,并详细阐述了“数字城市”的功能,为构建智慧城市奠定了一定的基础。

Temporal Three-Dimensional Ontology for Geographical Information Science (GIS)—A Review

While the use of three-dimensional (3D) geographical information system (GIS) is becoming in rapid development and being used in various fields such as urban and regional planning, disaster management and planning, mobile navigation and etc., commercial and open source GIS software packages tend to offer 3D-GIS functionalities for their products. On the basis, GIS analysis functions are to provide information with respect to geographical location and by having 3D spatial data as an input, it will give advantages in providing horizontal position information. However, to analyze moving objects (temporal) in 3D seems not an easy task and not fully supported by current GIS platform packages. Previously in two-dimensional (2D) GIS practice, main issue addressed by researchers in managing temporal spatial objects is GIS packages were designed based on hardware and software constraints whereby it should be based on the temporal spatial objects ontology. Nowadays, the trend of managing temporal 3D data is via 3D spatial simulation or animation. This approach will not in assistance for GIS users in conducting spatial queries. Without having a suitable ontology and valid topological data structure for temporal 3D data, it will cause repetitive of temporal data (redundancy) and complications in executing spatial analysis in 3D environment. Therefore this paper focuses on the ontology for managing moving 3D spatial objects (i.e. air pollution, flood). The characteristics of moving objects were reviewed thoroughly by categorizing it based on its different appearances. Moreover, existing methods in managing temporal database were addressed and discussed for its practicalities. Another important aspect in managing temporal 3D objects is the implementation of topological data structures for 3D spatial objects were reviewed. In the last section of this paper it summarized the issues and further ideas towards implementing and managing temporal 3D spatial objects in GIS based on the Geoinformation Ontology (GeO).

550kV GIS盆式绝缘子小型化设计(三)——缩比结构验证

为制造经小型化设计的550 kV盆式绝缘子并验证其电气性能,采用3D打印结合环氧树脂浇注工艺制备了1:10缩比绝缘子。首先,将氧化铝填料与光敏树脂复合作为低相对介电常数(3.98~4.20)3D打印浆料,根据光固化与流变特性确定填料含量及打印参数后,利用立体光固化3D打印机制备低介电常数的绝缘子主体。随后,将二氧化钛填料与环氧树脂复合作为高相对介电常数(11.32~14.58)真空浇注浆料,浇注至3D打印绝缘子预留的高介电常数区域内,加热固化完成缩比绝缘子的制造。0.2 MPa下SF6氛围中的工频耐压实验结果表明,优化后的绝缘结构具有更优的绝缘强度。相同绝缘距离下,几何形状优化绝缘子闪络电压较常规绝缘子提高13.6%,几何形状/介电分布联合优化的绝缘子提高13.8%;绝缘距离减少15%后,联合优化绝缘子耐电强度与常规绝缘子相当;当法兰侧“楔形”气隙内存在金属丝时,相同绝缘距离下,仅进行形状优化的绝缘子耐电强度提升幅度降低至6.7%,而联合优化绝缘子由于在法兰侧形成低电场区域,闪络电压仍可提高13.1%。结果表明,几何形状/介电分布联合优化绝缘子具有显著的绝缘优势。

Three-dimensional Building Damage Simulation Based on GIS

GIS technology has been applied to building damage analysis around the world. However, most previous studies focused on the application of 2-D GIS technology, and the results from traditional earthquake damage prediction are displayed in 2-D figures and charts, which is incapable of demonstrating the 3-D spatial characteristics of buildings. Taking brick-concrete building as an example, we study the characteristics of building damage, and effectively combine the information of building textures and earthquake damage. Then, we apply Google SketchUp techniques to create building models and display them with seismic damage texture in the ArcGIS Engine software development environment. In this paper we propose a solid idea for 3-D simulation of earthquake damage, which is helpful in earthquake damage prediction, virtual emergency rescue practice and earthquake knowledge education.

基于TEN的3D GIS数据模型及其生成算法

四面体网格 (简称TEN)是三维GIS中的一个重要的数据模型 ,文中首先提出了一种基于TEN的三维GIS数据模型 ;然后介绍了其中TEN的生成算法 ;最后本文总结了基于TEN的三维数据模型的优缺点。

基于X3D的网络3维GIS研究

在分析网络3维GIS研究现状基础上,指出当前网络3维GIS的不足,即VRML规范本身存在不足以及在地理信息共享与互操作方面存在局限。X3D是代替VRML的下一代交互式3D规范,支持XML格式的编码。提出一个基于X3D的网络3维GIS原型系统,试图克服传统网络3维GIS中的不足。

一种基于3D GIS的计算水库淹没区范围的算法研究

介绍了水库淹没区的基本概念,分析了传统基于二维的水库淹没区范围和基于DEM模型的水库淹没区范围2种计算方法的不足,及它们计算水库淹没区范围存在误差的原因。提出了一种基于3D GIS的计算水库淹没区范围的算法,并列举了所提算法用来计算水库淹没区范围的基本流程,论证了该算法在理论上的可行性和在实践中的有效性。