Function Analyses of Geographic Information System on Rural Distribution Network

With the actuality and characteristic and requirement of rural power enterprise distribution network management, this article introduced the function of geographic information system on the framework of distribution network, in order to develop rural distribution network.

Development and application of a GIS-based artificial neural network system for water quality prediction: a case study at the Lake Champlain area

Artificial Neural Network(ANN)models have been extensively applied in the prediction of water resource variables,and Geographical Information System(GIS)includes powerful functions to visualize spatial data.In order to provide an efficient tool for environmental assessment and management that combines the advantages of these two modules,a GIS-based ANN water quality prediction system was developed in the present study.The ANN module and ArcGIS Engine module,along with a dynamic database,were imbedded in the system,which integrates water quality prediction via the ANN model and spatial presentation of the model results.The structure of the ANN model could be modified through the graphical user interface to optimize the model performance.The developed system was applied to a real case study for the prediction of the total phosphorus concentration in the Lake Champlain area.The prediction results were verified with the monitoring data,and the performance of the developed model was further evaluated through graphical techniques and quantitative statistical methods.Overall,the developed system provided satisfactory prediction results,and spatial distribution maps of the predicted results were obtained,which coincided with the monitored values.The developed GIS-based ANN water quality prediction system could serve as an efficient tool for engineers and decision makers.

Exploring Crowdsourced Hard—Acceleration and Braking Event Data for Evaluating Safety Performance of Low-Volume Rural Highways in Iowa

There are over four million miles of two-lane roadways across the United States, of which a substantial portion is low-volume roads (LVR). Traditionally, most traffic safety efforts and countermeasures focus on high-volume high-crash urban locations. This is because LVRs cover an extensive area, and the rarity of crashes makes it challenging to use crash data to monitor the safety performance of LVRs regularly. In addition, obtaining up-to-date roadway information, such as pavement or shoulder conditions of an extensive LVR network, can be exceptionally difficult. In recent times, crowdsourced hard-acceleration and braking event data have become commercially available, which can provide precise geolocation information and can be readily acquired from different vendors. The present paper examines the potential use of this data to identify opportunities to monitor the safety of LVRs. This research examined approximately 12 million hard-acceleration and hard-braking events over a 3-months period and 26,743 crashes, including 9373 fatal injuries over the past 5-year period. The study found a moderate correlation between hard acceleration/hard-braking events with historical crash events. This study conducted a hot spot analysis using hard-acceleration/hard-braking and crash datasets. Hotspot analysis detected spatial clusters of high-risk crash locations and detected 848 common high-risk sites. Finally, this paper proposes a combined ranking scheme that simultaneously considers historical crash events and hard-acceleration/hard-braking events. The research concludes by suggesting that agencies can potentially use the hard-acceleration and hard-braking event dataset along with the historical crash dataset to effectively supervise the safety performance of the vast network of LVRs more frequently.

A Contention-Based MAC and Routing Protocol for Wireless Sensor Network

Advance development of wireless technologies and micro-sensor systems have enabled Wireless Sensor Network (WSN) to emerge as a leading solution in many crucial sensor-based applications. WSN deploys numerous resource-constrained sensor nodes which have limited power supply, memory and computation capability in a harsh environment. Inefficient routing strategy results in degraded network performance in terms of reliability, latency and energy efficiency. In this paper, a cross-layer design, Contention-based MAC and Routing protocol is proposed, termed Contention/SNIR-Based Forwarding (CSBF) protocol. CSBF utilizes the geographical information of sensor nodes to effectively guide the routing direction towards destination node, thereby enhancing reliability. Furthermore, Signal-to-Noise-plus-Interference Ratio (SNIR) metric is used as a routing parameter to guarantee high quality link for data transmission. A Contention-Winner Relay scheme is utilized to reduce the delays caused by the contention procedure. Energy efficiency is also improved by introducing sleep mode technique in CSBF. The simulation work is carried out via OMNeT++ network simulator. The performance of CSBF is compared with other existing routing protocols such as AODV and DSDV in terms of packet delivery ratio (PDR), average end-to-end (ETE) delay and energy consumption per packet. Simulation results highlight that CSBF outperforms AODV and DSDV protocols in respect of PDR and energy efficiency. CSBF also has the most consistent overall network performance.

A Decision Support System Web—Application for the Management of Forest Road Network

The present study contributes to the development of an online FRMP(Forest Road Management Platform)that aims to assist in the management of forest road network in a holistic way.This is achieved by the proposed methodology which serves as a database using geoprocessing and geospatial technologies for the handling,and the identification of critical issues in the infrastructure of forest road networks,visualization of forest roads,and the optimization of the management of the forest road network by proposing alternative strategies.In this paper,the development of the decision making web-tool,and presented examples to demonstrate effectively its application and resulting advantages are described.The developed web-application may provide assistance to various forest organizations in the management of forest road networks and associated problems in an effective and sustainable way.

Application of Wireless Network Positioning Technology Based on GPS in Geographic Information Measurement

Based on the analysis of the advantages and disadvantages of GPS positioning system in practical application,this paper proposes the combination of wireless network positioning technology and GPS positioning system to overcome the low accuracy of GPS positioning system in the case of occlusion.This paper introduces in detail the principle of the application of wireless network positioning technology based on GPS positioning system in geographic information measurement,and illustrates its practical application in production by taking coal mine positioning as an example.

Lifeline system network reliability calculation based on GIS and FTA

Lifelines, such as pipeline, transportation, communication, electric transmission and medical rescue systems, are complicated networks that always distribute spatially over large geological and geographic units. The quantification of their reliability under an earthquake occurrence should be highly regarded, because the performance of these systems during a destructive earthquake is vital in order to estimate direct and indirect economic losses from lifeline failures, and is also related to laying out a rescue plan. The research in this paper aims to develop a new earthquake reliability calculation methodology for lifeline systems. The methodology of the network reliability for lifeline systems is based on fault tree analysis （FTA） and geological information system （GIS）. The interactions existing in a lifeline system ale considered herein. The lifeline systems are idealized as equivalent networks, consisting of nodes and links, and are described by network analysis in GIS. Firstly, the node is divided into two types： simple node and complicated node, where the reliability of the complicated node is calculated by FTA and interaction is regarded as one factor to affect performance of the nodes. The reliability of simple node and link is evaluated by code. Then, the reliability of the entilre network is assessed based on GIS and FTA. Lastly, an illustration is given to show the methodology.

Models and Methods for Urban Power Distribution Network Planning

The models, methods and their application experiences of a practical GIS(geographic information system)-based computer decision-making support system of urban power distribution network planning with seven subsystems,termed CNP,are described.In each subsystem there is at least one or one set of practical mathematical methobs.Some new models and mathematical methods have been introduced.In the development of CNP the idea of cognitive system engineering has been insisted on,which claims that human and computer intelligence should be combined together to solve the complex engineering problems cooperatively.Practical applications have shown that not only the optimal plan can be automatically reached with many complicated factors considered, but also the computation,analysis and graphic drawing burden can be released considerably.

Navigation System for Foreign Tourists in Japan

The present study aimed to design, develop, operate and evaluate a sightseeing navigation system in order to support foreign tourists＇ efficient acquisition of sightseeing spot information in Japanese urban tourist areas, about which a variety of information is transmitted, by enabling information to be accumulated, shared and recommended. The system was developed by integrating Web-GIS （Geographic Information Systems）, SNS （Social Networking Services） as well as the recommendation system into a single system. The system used the non-language information such as signs, marks and pictograms in addition to English information, and displayed sightseeing spot information and conduct navigation on 2D and 3D digital maps of the Web-GIS. Additionally, the system was operated for two weeks in the central part of Yokohama city in Kanagawa Prefecture, Japan, and the total number of users was 54. Based on the results of the web questionnaire survey, all of the specific functions are highly evaluated, and the usefulness of the system when sightseeing was excellent. From the results of the access analysis of users＇ log data, it is evident that it can be said that the system was mainly used before sightseeing and users confirm their favorite sightseeing spots and made their tour planning in advance, using 2D and 3D digital maps.

LAN Tool: A GIS Tool for the Improvement of Digital Elevation Models Using Drainage Network Attributes

Digital Elevation Models (DEMs) are constructed using altitude point data and various interpolation techniques. The quality and accuracy of DEMs depend on data point density and the interpolation technique used. Usually however, altitude point data especially in plain areas do not provide realistic DEMs, mainly due to errors produced as a result of the interpolation technique, resulting in imprecise topographic representation of the landscape. Such inconsistencies, which are mainly in the form of surface depressions, are especially crucial when DEMs are used as input to hydrologic modeling for impact studies, as they have a negative impact on the model’s performance. This study presents a Geographical Information System (GIS) tool, named LAN (Line Attribute Network), for the improvement of DEM construction techniques and their spatial accuracy, using drainage network attributes. The developed tool does not alter the interpolation technique, but provides higher point density in areas where most DEM problems occur, such as lowland areas or places where artificial topographic features exist. Application of the LAN tool in two test sites showed that it provides considerable DEM improvement.

粤港澳大湾区内地城市群路网韧性的贝叶斯网络评估

随着我国城市化进程的推进,城市路网的韧性问题愈发凸显。构建了一种基于贝叶斯网络模型的城市路网韧性评价模型,并以粤港澳大湾区内地城市群为例,评估了2000—2019年该地区9个城市的路网韧性。基于韧性功能函数从容灾性、稳定性、重构性、恢复性4个方面建立功能层,选取稳定性、可变性、可维护性、可靠性、服务性、安全性、鲁棒性、可修性、适应性9个因素建立性能层,选取客运量、公共汽车数量、道路面积率、出租车数量、交通事故死亡人数、公共交通投资、每万人公共汽车数、道路运输从业人数、人均道路面积9个因素建立因素层。研究结果表明:路网韧性指数最高的为深圳(60%),而最低的为中山(43%);广州、深圳、珠海、东莞的路网韧性一直稳定增长,其余城市的路网韧性浮动较小;路网韧性并非总是随着城市GDP的增长而提高,还与人均GDP有关;敏感性分析表明,路网重构性、路网可靠性、交通事故死亡人数分别为各自所在层中对路网韧性影响最大的因素;加强中心城市与其他城市之间的联系可以提高城市路网韧性。研究成果可为粤港澳大湾区城市群交通路网功能完善与韧性提升提供技术参考。

面向地学分析AI建模的地理信息服务层次网络模型

在人工智能生成(AIGC)和大语言模型(LLM)的大背景下,如何提升地学分析模型构建的智能化水平已成为业界广泛关注的焦点。为此,本文提出地理信息服务层次网络模型5-HiNet,基于需求描述、抽象模型、功能模块、服务接口、函数实例的5层子网络结构对海量地学分析模型进行建模,由抽象到具体逐层描述地学分析模型的实现过程,固化模型中的知识,形成面向地学分析模型的完备知识体系。5-HiNet模型能够进一步与大语言模型(LLM)进行耦合,实现地学分析模型的智能化生成。本文通过原型系统和应用案例,初步验证了5-HiNet的可行性,并为未来研究和应用提供新的方向和思路。

基于GIS的青岛市绿地景观生态格局与网络构建

定量化研究绿地景观生态格局和网络构建能够为城市绿地系统和国土空间的科学规划提供理论依据与方法支撑。研究基于无线电高空测候(RS)和地理信息系统(GIS)技术,运用总体景观生态格局分析和梯度分析方法,选取12个景观指数,对沿海城市——青岛市的绿地景观生态格局从斑块类型水平和景观水平两方面进行了定量研究。结果表明:斑块类型水平上,区域绿地以大型斑块为主且占优势地位,防护绿地以大中型斑块为主,二者虽空间分布不均匀,但生态效益较好;附属绿地以中小型斑块为主,缺乏大面积绿地建设,景观破碎度高但符合公众游憩需求;公园绿地以小型斑块为主且数量较少,在城区集中分布。景观水平上,城市绿地景观类型较齐全,但整体破碎度高,中部地区景观破碎度高,南部与中北部地区绿地类型多样,景观破碎度高且景观形状较复杂。在此基础上,进而分析了青岛城市绿地景观生态格局存在的问题,提出了“一轴、三核、廊汇成网、节点密布”的城市绿地生态网络优化与构建方案,以提高各类城市绿地连接度水平,发挥绿地生态系统的整体效益。

基于改进加权距离的建成区布线及供电范围调整

针对建成区源荷空间发展与配电网供电范围调整及其建设改造之间的复杂耦合关系,提出一种基于改进加权距离的建成区布线及供电范围调整方法。首先,结合建成区与新建区自动布线的技术差异性,建立建成区配电网供电范围调整及其自动布线一体化优化框架;其次,提出考虑新增源荷归属动态调整的新建线路待选条数区间计算方法;然后,综合考虑负载率越限改进效果和源荷距离特征,提出基于改进加权距离的新建线路供电范围划分和基于混合整数线性优化的网架布局方法;最后,通过所提实例验证模型和方法的经济性与实用性。

在线社交网络中用户地理位置预测综述

随着智能移动终端的日益普及,人们越来越多地利用社交网络平台(如Twitter、新浪微博等)获取信息、评论和交流.虽然全球卫星定位系统(GPS)设备能够精确获取位置信息,但是大量用户出于隐私和安全的考虑不会直接共享自己的位置信息.因此,如何获取在线用户的地理位置成为了一个前沿的研究领域以及学术界和工业界共同关注的重要课题,并且成为众多下游应用的基础,例如基于位置的定向广告投放、事件/地点的推荐、自然灾害或疾病预警和网络犯罪的追踪等.详细总结了预测社交网络用户地理位置的方法、数据、评价体系和基础算法.首先,归纳了不同的定位任务以及相应的评价指标;其次,针对不同的任务梳理所用的数据类型和数据融合方式,并且,详尽分析了已有的信息抽取和特征选择方式及其优缺点;再次,对现有定位模型和算法进行分类,从地名词典、传统机器学习和深度学习3个方面对用户定位方法进行阐述和分析;最后,总结了社交网络用户地理位置预测的难点和面临的挑战,并展望该领域的发展趋势和未来研究所需要关注的方向.

顾及地理尺度的矢量建筑物变化检测方法

高现势性数据与现有矢量地理实体数据库融合和更新时,由于现有基础地理数据库具有特定规范、精度与比例尺要求,使变化检测异常困难。鉴于此,提出了一种顾及地理尺度的变化检测样本构建方法。首先通过数据匹配建立新旧矢量数据同名实体间的对应关系,再通过固定尺度地理单元和数学形态学方法将变化样本聚焦在局部显著变化区域,以提高卷积神经网络对变化信息的尺度感知力。通过实验确定了样本地理单元的合适尺度,并对比了AlexNet、GoogleNet与传统C4.5决策树模型的变化检测效果。结果表明,基于图像的深度学习方法优于基于矢量人工特征的C4.5模型;基于固定尺度单元样本库的变化检测模型明显优于基于外接矩形样本的构建方法,进一步验证了该方法的有效性。

动态能源与地理信息融合的光储充电站电动汽车充电路径引导

电动汽车(EV)的出行、充电行为在对交通系统运行规律造成影响的同时,也使得能源网络负荷的时空分布发生改变。为此,考虑光储充一体化系统的特点,结合大规模EV、区域路网、配电网以及光储充电站的动态信息,构建了精细化的车-站-路-网动态融合模型;在此基础上,分别从用户、交通路网、电网3个角度构建包含行程时间、交通拥堵情况、电网稳定性的多目标优化函数。针对当前模型的高复杂度,运用分层规划和双向搜索思路对LPA*路径规划算法进行改进,从而实现动态环境下的充电路径引导。以某市一区域路网为例进行仿真,结果表明:与现有的策略相比,所提充电路径引导策略能很好地解决因EV充电带来的局部道路拥挤、区域光储能源消纳不均衡等问题。

基于地理空间视角的南沙新区基础设施空间布局分析

完善的教育、医疗体系是衡量城市文明程度和支撑城市高质量发展的基础。本文基于基础性地理国情监测成果,在分析南沙新区交通路网基础设施空间布局现状的基础上,利用地理信息技术的网络分析与缓冲区分析方法,通过定性与定量相结合的方式,对南沙新区的教育、医疗机构等基础设施的可达性分析,从地理空间的角度评价南沙新区基础设施空间布局的合理性,为新区教育、医疗机构设施空间布局优化及未来新区基础设施规划选址提供技术方法与数据参考。

基于地理信息系统的配网自动化系统设计研究

地理信息系统的加入能够提高电网管理自动化水平,研究了基于地理信息系统的配网自动化系统。设计了配网自动化系统现场通信节点,对基于地理信息系统的配网自动化系统设计给出了总体方案。该研究可以为实现配网自动化、现代化发挥更大作用。