A Single-Site Positioning Method Based on TOA and DOA Estimation Using Virtual Stations in NLOS Environment

This paper presents a single-site positioning method based on the joint estimation of propagation time-of-arrival(TOA) and direction-of-arrival(DOA), with the assist of virtual stations in the typical non-line-of-sight(NLOS) environment. Consider the influence of multipath noise on the positioning performance, the proposed method firstly presents a modified high-resolution estimation technique called Multipath noise Limiting Matrix Pencil(MLMP) algorithm to achieve the TOA/DOA estimations, in which the matrix pencil and matrix enhancement process are implemented to deal with the measurements from the uniform linear array(ULA) receiver. Meanwhile, the subspace dimension estimation is improved via an adaptive threshold, for enhancing the performance of high-resolution techniques in low signal-noise-ration(SNR) situation. Next the proposed method generates virtual stations utilizing the known floor plan of surrounding reflectors, and adopts a weighted Least Square(WLS) position estimator to calculate the required position, combining the TOA/DOA estimations with the location of virtual stations. Simulations are conducted to evaluate the proposed method under NLOSconditions, and the results show that comparing with the multipath fingerprinting scheme, the proposed method has better performance in various simulation scenarios.

Preliminary site classification of free-field strong motion stations based on Wenchuan earthquake records

During the great Wenchuan earthquake, about 460 permanent free-field stations in National Strong Motion Observation Network System （NSMONS） of China captured the main shock acceleration records. These records can be applied to site effect analyses, and then the site classification of those permanent stations can be carried out firstly, which will served as the fundamental information for further research. In this paper, the site of near-fault stations is classified by horizontal-to-vertical spectral ratio （HVSR） method according to the site class description of Japan earthquake resistant design code and response spectral shapes （RSS） method following the site class description of the 1997 Uniform Building Code （UBC） provisions. Then based on the detailed borehole data of those free-field stations, the equivalent shear wave velocity and overburden thickness are calculated and the site classifications are given by Chinese code for seismic design of buildings. Furthermore, for the stations having successful microtremor test data, the site dominant periods are computed to verify the results of site classification. Finally, combined with all the above results, the recommended site classes of near-fault permanent free-field stations are given.

Research on Site Planning of Mobile Communication Network

In this paper,considering the cost of base station,coverage,call quality,and other practical factors,a multi-objective optimal site planning scheme is proposed.Firstly,based on practical needs,mathematical modeling methods were used to establish mathematical expressions for the three sub-objectives of cost objectives,coverage objectives,and quality objectives.Then,a multi-objective optimization model was established by combining threshold and traffic volume constraints.In order to reduce the time complexity of optimization,a non-dominated sorting genetic algorithm(NSGA)is used to solve the multi-objective optimization problem of site planning.Finally,a strategy for clustering and optimizing weak coverage areas was proposed.In order to avoid redundant neighborhood retrieval during cluster expansion,the Fast Density-Based Spatial Clustering of Applications with Noise(FDBSCAN)clustering method was adopted.With different sub-objectives as the main objectives,this paper obtained the distribution map of weak coverage areas before and after the establishment of new base stations,as well as relevant site planning maps,and provided three planning schemes for different main objectives.The simulation results show that the traffic coverage of the three station planning schemes is above 90%.The change in the main optimization objective will result in a significant difference between the cost of the three solutions and the coverage of weak coverage points.

楞古水电站V线右岸边坡深部裂隙成因及边坡稳定性分析

针对楞古水电站V线右岸边坡深部裂隙发育特征,以边坡工程地质条件及坡体结构为基础,结合嘎夏帕滑坡破坏模式对其深部裂隙成因进行了分析,认为其深部裂隙是由于边坡滑移-剪切变形所造成,且边坡缓倾角结构面发育程度决定了边坡深部裂隙分布范围及张开度。分析边坡深部裂隙变形程度,结合边坡整体稳定性FLAC3D模拟,得出蓄水后边坡上游侧稳定性较边坡下游侧更低,以后对边坡采取合理的支护措施提供了可靠的依据,并为同类水电站蓄水边坡稳定性研究提供了参考。

A mobile polar atmospheric parameter measurement system:Ⅱ. First atmospheric turbulence observation at Antarctic Taishan Station

This is the second paper of a series devoted to atmospheric optical turbulence Cn^2 observation using a mobile polar atmospheric parameter measurement system. We present the initial results of Cn^2 measurement at Antarctic Taishan Station using micro-thermal sensors and a three-dimensional sonic anemometer at height -2.0 m above the snow surface. The site testing experiments were carried out during the 30th Chinese National Antarctic Research Expedition （CH1NARE）. We collected about 1 000 h of data between 30 December 2013 and 10 February 2014. The C,： curve exhibits clear daily structures, with two peaks around midnight and midday and two troughs around 7：30 and 17：00 local time （UTC＋5）. The mean C,2 is 2.7×10^-15 m^-2/3 and the 25th and 75th percentiles of the C,2 cumulative distribution are 9.6×10^-16 m^-2/3 and 6.2×10^-15 m^-2/3, respectively. Meteorological parameters such as temperature, relative humidity, wind speed, and air pressure are also presented.

电动汽车集中型充电站选址定容模型

针对充电和换电等单一模式的盲目建设,规划不集中带来的资源利用率低与部分充电需求得不到满足等问题,本文提出一种考虑充电和换电与移动充电的多种充电模式下集中型充电站选址与定容方法。首先,分析不同类型电动汽车的充电行为特性,模拟得到规划区域的充电需求分布;然后,基于最近距离原则采用排队论方法计算电动汽车充电损耗成本,优化移动充电设备自充电时刻,求得电动汽车自充电成本;最后,以集中型充电站建设维护成本、用户损失成本及设备自充电成本总和最小为目标建立选址定容模型,结合某城市部分实际道路网为研究区域,采用遗传算法求解模型,确定规划区域内集中型充电站建设数量、位置及不同设备的配置数量。结果表明:规划区域内建设8座集中型充电站总成本达到最低,充电需求车辆数量与充电功率变化对集中型充电站成本均有较大影响,且优化移动充电设备自充电调度管理,可降低集中型充电站高峰时期32.62%的电网负荷,提高了电网稳定性。

Current State, Shortcomings, and Strategies to Improve China’s Waste Recycling Network: Optimization of Regional Site Selection for Waste Disposal Systems Based on Supply Chain Management

Based on the basic supply chain model,the status quo of waste recycling in China is examined by analyzing and comparing the changes in the waste recycling network and the problems of siting in relation to China’s waste disposal system.

基于IE的城市新能源汽车充电站选址优化研究

汽车产业一直是我国国民经济重要支柱,随着我国经济结构转型升级和环境保护综合治理的力度持续加大,新能源汽车普及已势在必行,但新能源汽车销量的陡增给未来城市功能结构调整带来动力和挑战,特别是新能源汽车充电站在城市的选址布局优化问题尤为突出。以城市新能源汽车充电站布局为研究对象,使用IE优化理论方法与技术工具,针对充电站选址过程中忽略人的出行需求,导致其选址结果不精确的现状,应用Logit回归分析确定居民出行新能源汽车分担率,从而判断使用充电桩的需求数量,提高了计算结果精准度;再应用联合覆盖模型,确定充电场站选址位置,优化充电场站中充电桩的配置数量,用户使用充电桩最大距离缩短至2 km。实现了以低成本高效率满足新能源汽车用户的充电需求,对城市未来新能源充电场站选址与布局具有一定借鉴意义。

CTCS-2+ATO列控系统对短站坪长度需求适应性研究

研究目的:对于有地下线路的铁路工程,由于开挖土方等方面的问题,要求站坪长度尽量缩短,以节省工程投资。现有CTCS-2+ATO列控系统因其安全防护距离设置位置、车载设备安装位置、适应的运行速度较高等原因,对站坪长度要求较CBTC列控系统长,成为在市域铁路运用时的不利因素,需要对其进行短站坪长度需求的适应性分析并提出适宜的解决方法,提升系统的竞争力。研究结论:(1)侧线股道增设安全线,基于列车停稳信息及时解锁过走防护区段、利用应答器报文增加过走防护区段信息、及时回缩列控移动授权范围等配套方法,将安全距离、附加距离设于目标点信号机的内方,利用安全线及咽喉区线路缩短股道区线路长度;(2)合理约束车载应答器接收天线安装位置,根据市域列车运行速度计算、确定可靠解析出报文所需要的应答器距离信号机距离,以及应答器组间最小距离要求,最终确定股道出站应答器安装位置最小长度需求;(3)经折返线道岔侧向的进路不发低频码,轨道电路长度仅考虑轨道占用检查时间,进一步缩短折返道岔区段长度要求;(4)本研究成果在市域铁路中有广阔的运用前景。

Optimal Siting of Electric Vehicle Charging Stations Based on Voronoi Diagram and FAHP Method

The electric vehicle charging station should be allocated based on traffic density, geographical distribution and other factors, and Voronoi diagram is adopted to set the service area of charging station. In combination with the actual situation of site selection of electric vehicle charging station, the comprehensive benefits index system is established. There are numerous factors influencing the site selection, among which there are uncertainty and fuzziness. The comprehensive evaluation method based on the fuzzy analysis and Analytical Hierarchy Process (AHP) is used to evaluate the comprehensive benefits in the site selection of electric vehicle charging stations, with the consultation of experts. This paper contributes to the best selection of comprehensive benefits and provides the reference for the decision-making of building the electric vehicle charging station. Actual examples show that the method proposed is effective.

Comparison of Soil Samples from Selected Anthropogenic Sites within Enugu Metropolis for Physicochemical Parameters and Heavy Metal Levels Determination

This study compared the physicochemical parameters and heavy metal levels in soil samples from selected anthropogenic sites within Enugu metropolis, Enugu State, Nigeria using standard analytical methods. Soil samples at depths (0 - 20 cm) and (20 - 40 cm) were collected from waste dump sites, metal scrap dumps, fuel filling stations and auto-mechanic workshops and analyzed for physicochemical characteristics and heavy metal levels. Atomic absorption spectrophotometer was used for heavy metal determination while conventional analytical methods were employed for physicochemical parameters evaluation of the soil samples. At soil depths 0 - 20 cm and 20 - 40 cm the respective mean range of pH, electrical conductivity, organic matter and organic carbon contents in the soil samples were, 6.33 - 6.74, 101.46 - 123.21 μS/cm, 6.41% - 8.35% and 13.73% - 16.14% for auto-mechanic workshops;6.92 - 7.43, 56.46 - 60.02 μS/cm, 1.53% - 2.20% and 11.93% - 12.60% for fuel filling stations;7.14 - 7.84, 70.81 - 77.71 μS/cm, 3.81% - 4.12% and 8.57% - 9.24% for metal scrap dumps;6.54 - 6.81, 94.40 - 100.71 μS/cm, 8.83% - 10.75% and 18.26% - 20.81% for waste dump sites. The pH of the top soil samples from auto-mechanical workshop was below the WHO recommended limits for agricultural purposes. The physic-chemical characteristics of the soil samples decreased with soil depths indicating therefore that anthropogenic activities greatly influence the soil characteristics at the top soils than the sub-soils. The electrical conductivity values of top and sub-soil samples from the studied auto-mechanical workshops were above the recommended limits. At soil depths 0 - 20 cm and 20 - 40 cm, the respective mean range of Zn, Pb and Cd in the soil samples were 17.29 - 19.16 μg/g, 0.704 - 0.96 μg/g and 0.26 - 0.33 μg/g for auto-mechanic workshops;4.13 - 4.88 μg/g, 0.21 - 0.32 μg/g and 0.03 - 0.11 μg/g for fuel filling stations;30.02 - 36.11 μg/g, 0.43 - 0.48 μg/g and 0.15 - 0.19 μg/g for metal scrap dumps;9.30 - 10.84 μg/g, 0.53 - 0.60 μg/g and 0.38 - 0.45 μg/g for waste dump sites. The mean levels of Pb in soil samples from mechanic workshops and waste dump sites were above the recommended permissible limits for agricultural purposes. The study therefore indicated that these sites (auto-mechanic workshops and waste dump sites) could be major sources of Pb pollution to nearby farmlands, streams and the general environment. Plants grown on or around these sites may not produce high yields and could be severely contaminated with heavy metals which portend health danger to food consumers within the environment.

基于POI数据的公共免租站点数字化检测策略探索与应用

在5G网络大规模部署和刚性成本快速增长的局势下,为了节省基站建设场地租赁费用以及制定有效的选址策略,文章提出了一种公共免租站点智能检测的方法。该方法利用中文切词算法挖掘公共免租站点关键词并建立公共免租关键词库,引入广泛的POI数据、基站数据以及合同数据进行匹配和交叉运算,实现系统化、智能化地检测现有站点是否满足公共免租条件。通过建设公共免租关键词库,辅助锁定存量租用的现网物业站点,并以公共免租谈判的手段进行推动,有效地摆脱了传统人工判断的主观性与不确定性,为基站选址决策者提供可靠的参考,从而降低基站租金成本,提高5G网络的经济效益。

基于两级接力的5G海域超远覆盖创新实践

海洋覆盖的关键是站点的海拔高度,对于沿海以平原为主的地区,常规手段难以实现5G海域超远覆盖。提出一种基于两级接力的5G海域超远覆盖方案,通过在海上平台部署海基站,与陆地岸基站实现两级接力的方式实现海域超远覆盖,并通过实测验证了方案的有效性。

基于改进多目标遗传算法的5G基站选址布局研究

5G基站的建设是5G产业链中十分重要的一环。对于运营商而言,基站的选址规划会直接影响5G网的信号质量和使用效率。针对基站选址规划不合理的问题,本文考虑了不同区域基站覆盖范围不同和网络业务量不同的特点,以基站建设成本最小、面积覆盖率和业务覆盖率最大为优化目标,建立了5G基站选址优化模型,使用改进的NSGA-Ⅱ算法对模型进行求解。仿真结果表明,该算法有效解决了基站选址问题,并且具有速度快、效率高、不易陷入局部最优解等优势。

考虑火灾风险与多级覆盖的城市消防站选址优化

为进一步优化城市消防服务不完善等问题,将城市火灾风险评估和多级覆盖选址模型相结合,对城市消防站选址进行合理优化。首先,运用模糊层次分析法对城市火灾风险进行评价,结合ArcGIS空间分析功能得到城市火灾风险值。然后,将火灾风险值引入最大覆盖模型,同时考虑最小救援距离。以现有消防站的数量和对火灾风险点的覆盖率为约束条件,建立多目标消防站选址优化模型,并利用NSGA-Ⅱ算法对其进行求解。最后,以武汉市主城区为实例研究对象来验证模型的科学性和有效性。研究结果表明:利用多目标选址优化模型求解的候选消防站和现状消防站相比,在兼顾火灾高风险地区的特殊考虑同时,能有效提升对火灾低风险地区的覆盖。研究结果可为武汉市的消防服务及消防站选址规划提供一定参考。

改进非洲秃鹫算法的汽车充电站选址方法

充电站选址需要综合考虑多个因素,如充电需求密度、车流密度、车速等,这些因素之间存在复杂的相互关系和约束条件,如何将它们综合考虑是一个难点。为了获取用户满意度较高的选址方案,提出一种考虑交通拥堵的新能源汽车充电站选址优化方法。考虑交通拥堵指数对新能源汽车用户出行和充电站选取的影响,以运营商投资成本最小和用户满意度最大为目标,建立新能源汽车充电站选址优化模型。利用改进非洲秃鹫优化算法对模型求解,确定新能源汽车充电站选址最优解决方案。仿真实验结果表明,所提方法可以有效提升用户满意度,减少网损率和路径长度,获取更加贴合实际需求的新能源汽车充电站选址方案。

无人机抛投式GNSS滑坡监测设备智能化部署选址方法

GNSS技术广泛应用于滑坡形变监测,而复杂艰险的高危滑坡往往人员难至,导致GNSS监测设备安装困难。无人机抛投部署技术为解决此问题提供了可能,然而其前提是为无人机抛投提供适宜的目标部署位置,传统的选址方法主要依赖专家现场踏勘评估,无法满足该场景应用需求。为此,本文首先利用无人机航测、InSAR-Stacking技术获取选址区域的DSM、DOM及地表历史形变速率图,然后基于深度学习、地形分析等方法提取历史形变、裂缝分布、坡度、地表粗糙度、植被指数、坡向等选址因子,最后基于层次分析法对多个选址因子进行决策融合,智能化评估滑坡区域内不同位置的选址适宜性并推荐无人机抛投式GNSS监测设备的目标部署位置。以甘肃黑方台滑坡区域为例开展选址试验,评估了该区域内的选址适宜性并推荐了4处GNSS监测设备部署位置,现场情况及历史站点形变序列验证了本文方法的有效性。本文方法综合考虑了形变监测、部署难度、观测条件及持续运行等需求,可高效评估选址区域内设备部署的适宜程度,对于提升无人机抛投式GNSS监测设备的部署效率及监测效果具有重要参考价值。

交通网-电网耦合框架下制氢加氢站选址定容

制氢加氢站(HPRS)的合理规划对氢燃料电池车的发展具有重要意义,为此提出交通网-电网耦合框架下的HPRS规划方法,实现大规模分布式新能源并网电力系统下的HPRS选址定容。首先,基于城市路网阻抗信息模型对氢燃料车的出行进行模拟,得到交通网层面上加氢负荷时空分布。然后,以建设运营成本、交通网加氢负荷覆盖率与电力网络运行稳定性为约束,构建多目标综合评价选址定容模型,通过改进粒子群算法对HPRS的选址和设备容量进行求解。在33节点电网和25节点交通网上进行算例分析,结果表明所提出方法有效降低了HPRS在接入电网后引起的电网损耗与电压偏差,同时提升新能源自消纳率,提高了HPRS的交通网服务质量并减少了建设运营成本。

NB/T 35009-2024修订内容解读及抽水蓄能电站标准化工作历程回顾

本文回顾了抽水蓄能电站选点规划标准化工作历程,从90年代选点规划工作范围逐步扩展,一批代表性站点规划落地,选点规划思想逐渐成熟,首版标准于2003年编制完成。到2009年全国范围抽水蓄能电站选点规划系统性开展,继22个省(区、市)完成选点工作,第二版标准修订完成,有效指导了实践工作。随着抽水蓄能电站选点规划的管理流程和技术路线不断成熟,选点规划已成为前期工作和开工建设的重要基础。双碳目标提出以来,抽水蓄能中长期发展规划为行业发展带来新机遇新挑战,第三版标准修订工作适时开展,区分功能定位、明确技术要求,积极响应了当前新能源和抽水蓄能行业高质量发展的要求。