机动管线线路管理三维可视化模型探讨

本文探讨了适合机动管线线路管理的三维管线几何模型,采用断面与体面三角剖分拟合方法构建直管线、弯曲管线的三维模型,利用专业3D软件对管件及泵站装备进行符号化处理,给出了管线建模的方法和步骤。     

基于BIM+GIS的铁路三维信息实景化技术研究

BIM+GIS技术可用于铁路环境的模拟分析,目前在BIM模型信息的语义场景转化方面的扩展尚显不足,造成部分BIM模型转化后信息冗余或缺失的现象。针对此问题,提出一种坐标转换方法,将铁路BIM模型相对坐标转化为GIS地理坐标,并设计了一种考虑铁路场景复杂度的三维模型与GIS地形匹配方法,以实现铁路BIM模型在不同三维场景下的精确匹配,基于构建的对象重要性评价模型,实现了符号化三维铁路场景多尺度表达,该方法有效解决模型漂浮或模型淹没等问题,满足大比例尺下探析三维场景要素和目视精确定位的场景需求,同时兼顾铁路BIM模型轻量化按需加载的应用要求。研究成果解决了铁路BIM模型与三维GIS地理场景精确匹配与表达的技术难题,具有较高的理论意义和工程实践价值。     

基于CAXA与CATIA的船体三维建模技术比较分析

对300箱多用途集装箱船船体结构进行生产设计,分别使用CAXA和CATIA实体软件完成三维建模,着重研究船体构件建模和装配模拟,展示三维设计技术在船舶生产设计中的应用。对国产软件CAXA和大型造船三维软件CATIA在曲面造型和参数化设计等方面的功能进行比较分析,进一步研究探讨三维建模技术在船体复杂曲面生产设计中的运用。     

检测数据全息可视化系统设计与实现

在对空间、时间和业务属性数据关联性聚合的基础上,利用地理信息系统技术、三维虚拟现实技术和多媒体技术将高速综合检测列车的检测数据统一在一个三维GIS可视化系统上进行展现.采用数据层、服务层、接口层、应用层、客户层的5层架构模式进行系统结构设计,利用MapABC与AnGeo二三维平台相结合的方式进行二三维数据一体可视化,实现了二三维数据的融合与实时联动;解决了高速运动条件下三维场景快速加载及全息可视化等关键技术,为检测数据的综合分析和展示提供了新的思路和方法.     

基于微课程的“三维建模技术应用”教学设计

微课程是一种新型的教学模式,是信息化技术与现代化教学在碎片化时间下的新融合。文章在对微课程内涵分析的基础上,结合"三维建模技术应用"课程的教学要求,就微课程教学设计中的关键环节进行剖析与设计,为同行提供参考。     

基于BIM+3D GIS技术的公路三维信息应用研究

正目前,我国BIM技术在公路领域的应用刚刚起步,本文将实际的公路工作与三维地理信息系统(3D GIS)技术、BIM技术、云计算、大数据、移动互联网等先进技术和理念结合起来,对BIM+3D GIS技术在公路管养中的应用进行研究,以期在现有公路BIM数据采集处理方法、公路BIM建模方法及其应用等方面有所启示。     

基于路基病害的地质雷达探测模型与数值模拟探究

为降低路基沉降等病害对公路结构产生的负面影响,有必要快速而准确地探测出病害存在的区域和形状,继而采取有针对性的治理措施。基于此,本文探讨了针对公路路基病害的地质雷达探测技术,通过构建公路路基病害的地质雷达探测模型,总结分析了路基疏松、局部沉降和路基空洞等病害的数值模拟特征。结果显示,使用地质雷达探测公路路基病害时,检测速度较快且所得结果准确,具有良好的实践应用价值。     

空间数据仓库技术及其建模研究

空间数据仓库（Spatial DataWarehouse）是GIS技术和数据仓库技术相结合的产物，它大大扩展了GIS的应用功能。为逐渐兴起的全球变化和区域持续发展研究以及复杂的商业地理分析提供了强有力的支持。本文论述了空间数据仓库的背景、定义及功能特征，分析了空间数据仓库的体系结构，并对其建模技术进行了研究。     

高速公路填砂路基施工技术

本文介绍了静力压实法、冲击压实法与振动压实法三种常用的路基压实方法,分析了含泥量、含水量对路基质量的影响以及填砂路基的特殊结构,结合工程实践,制定一套填砂路基的施工工艺,并对路基平整度、压实度与沉降量进行检测,可为高速公路填砂路基的施工技术提供参考。     

关于某高速公路路面开裂的原因分析

基于某高速公路T1/T2互通k39+405～k39+543段路面出现的纵向裂缝,通过三维激光扫描、物探数据采集、钻芯和开窗取样及地形测量等勘察方式,结合实际勘察情况及资料,从工程建设情况、外围河道整治、路基水平位移和沉降等方面系统分析,发现造成路面开裂的主要原因为路基滑移和沉降。     

基于非集计模型的交通方式选择研究

基于非集计模型的基本理论与建模方法,依据2002年重庆市主城区综合交通调查数据,建立了交通方式选择MNL模型,通过多项logistic分析对模型进行标定,并用2008年居民出行调查数据检验模型精度.所建立的模型亦用于研究影响交通方式选择的关键因素,通过对可控影响因素的引导和调整,达到优化交通方式结构的目的.研究结果表明,非集计模型较集计模型能更好地表达居民出行方式选择行为,有利于交通方式结构的调整和优化.     

Determining intra-urban spatial accessibility disparities in multimodal public transport networks

Urban rail systems have been added to public transport systems, thereby changing distribution disparities in urban spatial accessibility. These disparities reflect both the ability of the public transport system to meet the needs of residents and the locational pros and cons of public service facilities. In this paper, integrated accessibility metrics are used to assess the disparities in Nanjing, Jiangsu Province, China. This is achieved by dividing the urban space into a multilevel grid that can be easily combined with grid-based population data to facilitate accessibility modeling, calculation, and evaluation. Additionally, an acquisition method for more accurate travel time data in the multimodal public transportation network was developed on the basis of an Internet mapping service. This provides a realistic, multimodal, door-to-door modeling approach that avoids the requirement of building complex traffic networks through Geographic Information System (GIS) software and simplifies road network modeling efforts. The results show that this modeling method can be used to reflect the accessibility disparities in the Nanjing urban space objectively and accurately.     

基于系统控制机制的动态物流联盟建模研究

在阐述物流系统建模技术研究的基础上，提出基于系统控制机制的动态物流联盟建模思路，核心思想是采用合理的控制方式，使具有不同优化目标的决策过程间实现最大程度的一致性。为此建立了基于整子控制机制的动态物流联盟模型的总体架构，并建议采用递阶控制机制协调子系统内部的过程联系。     

Exploring the Implications of Virtual Reality Technology in Tourism Marketing: An Integrated Research Framework

The proliferation of the Internet and other technological innovations has transformed the structure of the tourism industry as well as affected how tourism destinations are perceived and consumed. The 3D virtual world provides opportunities for destination marketing organizations to communicate with targeted markets by offering a rich environment for potential visitors to explore tourism destinations. However, as of yet, there is little understanding about how to effectively market tourism destinations to virtual world participants who are technology users as well as potential consumers. The purpose of the present study is to develop a research framework that integrates the technology acceptance model (TAM) and self‐determination theory to understand how tourists use a 3D virtual world. Primary data were obtained for this study through self‐administered Web questionnaires. The data were conducted in a laboratory setting with 186 participants. This study contributes to the empirical TAM literature by applying the model to a 3D virtual tourism site. Additionally, this study provides a research framework to capture the entertainment nature of a 3D virtual world by extending the TAM to incorporate psychological elements of self‐determination theory to understand consumer experience. From the perspective of tourism professionals, this study contributes to an understanding of how best to construct informative and interactive tourist destinations in 3D virtual worlds to attract potential online and real‐world tourists. Copyright © 2015 John Wiley & Sons, Ltd.     

路基浆砌片石骨架护坡施工的质量控制

浆砌片石骨架护坡是路基防护的常见形式，其质量对确保路基安全十分重要。结合路基浆砌片石骨架护坡施工中容易发生的问题，从材料选择、基坑开挖、砂浆制作、砌筑方法、养护及施工工艺控制、质量检测等方面，分析质量通病的形成原因，提出控制浆砌片石骨架护坡施工质量的针对性措施。     

Modeling downstream petroleum supply chain: The importance of multi-mode transportation to strategic planning

This paper proposes a deterministic mixed integer linear programming (MILP) model for downstream petroleum supply chain (PSC) network to determine the optimal distribution center (DC) locations, capacities, transportation modes, and transfer volumes. The model minimizes multi-echelon multi-product cost along the refineries, distribution centers, transportation modes and demand nodes. The relationship between strategic planning and multimodal transportation is further elucidated. A case study was considered with real data from the U.S. petroleum industry and transportation networks within Geographic Information System (GIS). A scenario analysis is also conducted to demonstrate the impact of key parameters on PSC decisions and total cost.     

Optimizing high-speed rail routes using a Spatial Decision Support System (SDSS): the Texas Urban Triangle (TUT) case

Previously, an analytical method was derived to model a possible high-speed rail route within the Texas Urban Triangle (TUT) area. By implementing a raster-based geographic information system (GIS), researchers were able to optimize a route with the given variables. Based on prior research outcomes, the authors improved the overall analytical approach. This article expands the study boundary from Travis County through Bexar County to test the corridor between the San Antonio and Austin metropolitan areas. Nearby counties are also included, resulting in a total of six counties. In addition, a statistical tool, explanatory factor analysis (EFA), is added to fill the gap identified in the previous modeling practices. The project addresses transportation corridor planning in the Texas Urban Triangle at the regional scale. Its aim is to determine the most suitable locations for new transport infrastructure by employing a Spatial Decision Support System (SDSS). The proposed SDSS provides a composite foundation for decision making to attain enhanced regional mobility, especially for a high-speed rail (HSR). Route alternatives are compared in terms of construction estimates, anticipated land acquisition fees, and suitability scores.     

统一授信存货质押下第三方物流选择研究

选择合适的第三方物流是统一授信模式存货质押业务顺利开展的关键环节.在对国内外存货质押研究现状进行分析的基础上,从市场竞争力、监管技术水平、品牌与信誉及地域交通4个方面构建统一授信存货质押下第三方物流选择的评价指标体系,建立了层次分析法与灰色评价相结合的多层次灰色评价模型,研究银行开展统一授信存货质押业务中如何选择第三方物流,并通过案例说明模型的有效性.     

Traveling in the three-dimensional city: applications in route planning, accessibility assessment, location analysis and beyond

Indoor environments are increasingly important spaces in contemporary three-dimensional cities. Handling these micro-scale spaces within the broader context of outdoor - urban environments is a significant challenge in transportation analysis and geographic information science. This complexity stems from the greater computational requirements, the specificity of indoor network data structures, as well as the inherent perceptual intricacies of 3D visualization. As built environments grow in size and in complexity, two-dimensional urban geography research reveals its limits. This paper advocates for 3D network-based urban research and showcases the feasibility of this approach for three specific types of urban analytical functionalities, namely route planning, spatial accessibility assessment, and facility location planning. The latter modeling functionality can be viewed as foundational elements for comprehensive network-based three-dimensional analytics of urban environments. The effectiveness of the data modeling scheme and of the integrated software application 3DCityNet is discussed through the three coupled geospatial modeling functionalities.     

A spatially explicit techno-economic model of bioenergy and biofuels production in California

This study presents a spatially explicit techno-economic Bioenergy Siting Model (BSM) of the bioenergy production system in California. The model describes the bioenergy system in terms of facility siting and size, conversion technology, feedstock profile, and feedstock supply chain configuration for the year 2015. The BSM expands upon previous bioenergy siting work by optimizing the system using spatially explicit feedstock supply curves, multiple potential conversion technologies and geographically determined bioenergy demand. We present sensitivity analysis demonstrating the effect of market and policy change scenarios. The model couples transportation network analysis using a Geographic Information System (GIS) with a mixed integer-linear programming (MIP) optimization model. Scenario results show total biomass resource utilization between 18 and 25 million dry tons annually at biofuel prices from $2.20 to $4.00/gallon of gasoline equivalent.