大型设备的基础放样和安装测量方法

结合轧机基础施工和设备安装实例,总结了设备基础施工放样和安装测量中具有普遍性的技术工作,针对特殊预埋件的放样定位采用独立建网一次固定的方法,设备安装采用专用控制网,通过角度严密归方、精密校正距离的方法,用高精度测量仪器直接控制安装施工,保证了基础预埋件位置的准确和设备各机组之间严密的位置关系。     

精密设备安装放样与质量控制探析

近几年来,随着自动化及人工智能的普及,许多工厂作业线上的工作人员已被机器取代,而这些设备的安装,对点位精度要求非常高。本文通过精密放样测量在设备安装中的应用实例,对精密放样测量的方法及精度的控制进行了探讨,总结出了一些运用中的经验。     

浅谈准直测量技术在工业测量系统中的应用

在精密工程测量中,大型设备精密制造和安装,对测量工作提出了更高的要求。通过对平面镜和立方镜准直技术的研究,运用MetroIn系统建立或者恢复高精度的坐标系,实现对高精度设备的制造和安装,该方法成为精密工程测量界重点研究的方向之一。     

利用原基础的大型设备安装测设问题探讨

工程测量中有时会遇到设备的重装和利用原基础安装新设备的问题 ,本文结合实例就在原基础上进行设备安装时的测设问题作了有益探讨。     

第三讲 核电站建设的安装测量

在核电站建设的安装测量中，最有核电特色的是环形吊车，压力容器，堆内构件，主泵、蒸发器、装卸料机轨道等安装测量工作，这些设备要求精度高，施工条件差，难度大，这一讲将对这些设备的安装测量作详细介绍，丽其它设备的安装测量比较简单，就不再介绍。     

亚毫米级预埋件定位技术研究

大型精密设备预埋件安装存在精度要求高、施工影响大、工期短等特点,需要采取稳定可靠的定位安装措施来保证预埋件亚毫米级精度要求,本文通过对预埋件安装及浇筑混凝土过程中误差来源的分析与相关公式的推导,探讨消除或减弱定位及施工对预埋件安装精度影响的方法,并用实例进行了说明和验证.     

反应堆内主要设备安装测量方法探讨

反应堆内设备的安装测量是核电建设中的关键性工作,其测量环境突出,观测条件差,而且观测精度要求高,安装定位精度要求达到0.1 mm,甚至更高.主要探讨反应堆内压力容器、装卸料机、主泵和蒸发器等主要设备的安装测量方法.     

工业摄影测量技术在核岛三维控制网建立中的应用

论述工业摄影测量技术在核岛安装三维控制网建立中的应用,为满足核岛设备安装定位高精度设计要求,须建立核岛精密三维控制网,获取设备安装定位测量基准坐标信息.采用工业近景摄影测量技术对分布于设备房间的基准点多角度、多位置拍摄,利用专用测量软件对高清影像处理与平差,获取各基准点空间坐标.通过工业摄影测量技术实现核岛三维控制网的网型布设、点位观测、数据处理,提高测量精度,提升施工效率,满足核岛设备安装定位测量需求.     

制浆造纸专业设备安装工程中的精密放样测量

讨论了机械设备安装工程施工过程中的精密放样测量内容、施工控制网建立、测量方法及精度控制,总结出了一些高精度设备安装测量中的经验。     

安装航车航轨测量工作点滴

本文主要对大型设备的安装测量工作方法和步骤以及精度要求进行了分析总结。提出的一些建议，对于开展工程测量工作具有一定的实际意义。     

1999—2020年长江经济带(江苏段)生态环境变化监测及人类活动驱动分析

协调区域城镇化与生态环境保护之间的关系,是推动我国长江经济带可持续发展的核心问题之一.针对现有研究中,生态环境变化与人类活动驱动之间的响应关系缺少时空对应的数据支持、影响过程不明的问题,本文充分利用多源卫星遥感技术在处理和提取时空信息上的优势,以长江经济带江苏段沿江县区为例,利用1999—2000年、2009—2010...     

北斗在地壳形变监测中的应用进展

北斗卫星导航系统(BDS)于2020年建成并开始向全球提供服务。如何提高其在防灾减灾领域的应用是目前关注的焦点。本文梳理了国内外采用BDS数据开展地壳形变(包括同震和震间形变获取)研究的现状,总结了BDS数据的定位精度,归纳出基于BDS数据的地壳形变监测需要进一步解决、有待拓展的关键问题:①扩展GNSS地壳形变监测的内涵,采用GPS与BDS双模或多模算法提高形变解算精度;②开展BDS实时形变监测在地质灾害早期识别中的应用;③开发、发布相关数据处理算法与软件系统,切实推进BDS在高精度地壳形变监测领域的应用。     

Satellite Earth observation data to identify anthropogenic pressures in selected protected areas

Protected areas are experiencing increased levels of human pressure. To enable appropriate conservation action, it is critical to map and monitor changes in the type and extent of land cover/use and habitat classes, which can be related to human pressures over time. Satellite Earth observation (EO) data and techniques offer the opportunity to detect such changes. Yet association with field information and expert interpretation by ecologists is required to interpret, qualify and link these changes to human pressure. There is thus an urgent need to harmonize the technical background of experts in the field of EO data analysis with the terminology of ecologists, protected area management authorities and policy makers in order to provide meaningful, context-specific value-added EO products. This paper builds on the DPSIR framework, providing a terminology to relate the concepts of state, pressures, and drivers with the application of EO analysis. The type of pressure can be inferred through the detection of changes in state (i.e. changes in land cover and/or habitat type and/or condition). Four broad categories of changes in state are identified, i.e. land cover/habitat conversion, land cover/habitat modification, habitat fragmentation and changes in landscape connectivity, and changes in plant community structure. These categories of change in state can be mapped through EO analyses, with the goal of using expert judgement to relate changes in state to causal direct anthropogenic pressures. Drawing on expert knowledge, a set of protected areas located in diverse socio-ecological contexts and subject to a variety of pressures are analysed to (a) link the four categories of changes in state of land cover/habitats to the drivers (anthropogenic pressure), as relevant to specific target land cover and habitat classes; (b) identify (for pressure mapping) the most appropriate spatial and temporal EO data sources as well as interpretations from ecologists and field data useful in connection with EO data analysis. We provide detailed examples for two protected areas, demonstrating the use of EO data for detection of land cover/habitat change, coupled with expert interpretation to relate such change to specific anthropogenic pressures. We conclude with a discussion of the limitations and feasibility of using EO data and techniques to identify anthropogenic pressures, suggesting additional research efforts required in this direction.     

基于Sentinel-1的长江干流水域面积动态变化遥感监测

本文利用Sentinel-1数据获得了2016-2020年月度长江干流上海-宜宾段水域面积,并分析其年际、年内变化规律。分析结果表明,①月度变化规律为1-5月水面面积变化相对平稳,6-8月水域面积逐步增加,在7月达到峰值;9月稍有回落,10月再次达到峰值后逐步减少至稳定。②季节性变化规律为冬季水域面积最小,夏季水域面积最大,夏季和冬季呈现明显的季节差异。③年际变化规律为2016年后水域面积呈增长趋势,其中2017-2019年水域面积相对稳定且缓慢增长,2020年面积急剧增长。分段而言,水域面积随时间的变化幅度为下游>中游>上游,中上游变化相对平稳,下游较显著。④易发生洪涝的断面主要分布在中下游段,需引起重视并做好监测预警。     

GIS中的数据转换与代数同构分析

对GIS中常见的数据转换进行了细致的研究 ,为数据转换中的质量保证提供了一种理论上严谨的检验手段 ,首次提出了用代数同构的思想来检测网络环境下数据共享的可信度     

A Visual Art Interface to an Embedded Sequence of Maps

The role of art in relation to maps is being reappraised on the basis of a perceived ability to depict aspects of a place that maps alone cannot. Many as opposed to one perspective on a place communicates more fully the essence of that place (with art as a valuable source of qualitative geospatial data) and so maps and art should be presented in the same visualization package. This paper outlines the development and implementation of an interface where a scanned painting forms the mode of access to an embedded sequence of maps. The interface is used to represent the history and habitat extent of the kea (alpine parrot) in New Zealand from pre human colonization times through to their present, limited range to a speculation on their future habitat. The painting and the map (in what has been termed in the literature as an anti-map / map combination) are in their own separate layers and joined by an interactive link. The interface harnesses the ability of visual art to aggregate multiple themes, locations and times into a single cohesive image, coupled with map composition and symbology that complements the painting. The ability to contain many temporal instances is close to the comic strip frame (and instances of Renaissance art) in particular, with, in this case, an implicit time frame from left to right on the painting. The use of an artistic image minimizes use of text to depict events, due to the visual and narrative power of the painting.     

Integrating Sketch Maps with GIS to Explore Fear of Crime in the Urban Environment: A Review of the Past and Prospects for the Future

Understanding the spatial dimension of fear of crime in the urban environment is important to understanding behaviors in response to this concern. Making this connection between perception and action has long been a goal of scholars in the social and health sciences, though this complex relationship has yet to be fully elucidated. Specifically, in studies on fear of crime and its influence on behavior, a variety of definitions and methods have been employed. This situation has yielded insights, as well as inconsistencies. In the past decade, Geographic Information Systems (GIS) has been added to this methodological mix, though it too has contributed limited understanding of the environmental perception-behavior nexus. During this time, some scholars have integrated a traditional technique for accessing environmental perception, the sketch map, with this newer technology. This article provides a review and critical assessment of the way GIS has been used to understand fear of crime, specifically through the integration of sketch maps. This focus is framed by an overview of substantive and methodological concerns and concludes with a discussion of continued research needs. As behavioral responses to fear of crime are acknowledged to impact physical and mental health and overall well-being, in addition to the viability of neighborhoods, research in this area will continue apace. However, for integration of sketch maps in GIS to be a valuable methodological contributor to this line of inquiry, users of the approach must understand its complexities. This article outlines these issues so that they may be considered in future research and may improve the ability for this approach to yield new understanding of fear of crime.     

A geometric-based approach for road matching on multi-scale datasets using a genetic algorithm

Object matching is used in various applications including conflation, data quality assessment, updating, and multi-scale analysis. The objective of matching is to identify objects referring to the same entity. This article aims to present an optimization-based linear object-matching approach in multi-scale, multi-source datasets. By taking into account geometric criteria, the proposed approach uses real coded genetic algorithm (RCGA) and sensitivity analysis to identify corresponding objects. Moreover, in this approach, any initial dependency on empirical parameters such as buffer distance, threshold of spatial similarity degree, and weights of criteria is eliminated and, instead, the optimal values for these parameters are calculated for each dataset. Volunteered geographical information (VGI) and authoritative data with different scales and sources were used to assess the efficiency of the proposed approach. According to the results, in addition to an efficient performance in various datasets, the proposed approach was able to appropriately identify the corresponding objects in these datasets by achieving higher F-Score.     

Evaluating the performance of high-resolution satellite imagery in detecting ephemeral water bodies over West Africa

Pastoralism is a major occupation in Africa’s Sahel region, which spans from Senegal in the west to Ethiopia in the east and has a semi-arid climate. Pastoralists from the region are usually nomadic, moving regularly in search of water and pasture, often for hundreds of kilometers. Traditionally, pastoralists have relied on historical knowledge and transhumance pathways to reach the water bodies (WB). Due to climatic conditions, a vast majority of the WBs in this region are small, sporadic, and ephemeral, therefore there is a need to map and frequently monitor water availability. Remote sensing observations can be used to complement current monitoring efforts. High-resolution near-daily imagery from the recently launched PlanetScope (PS) constellation of small satellites has the potential to complement the existing medium-resolution and infrequent but well established and extensively calibrated sensors like Landsat. The aim of this study is to investigate the performance and applicability of high-resolution PS data to detect and monitor WBs in the Ferlo region of West Africa, in comparison to Landsat-8 imagery. The results indicate that for cloud-free days, PS data was comparable (r >0.88; ubRMSE <0.01) to Landsat, but due to inadequate cloud masking, the results were poor for cloudy days (r < 0.49 and ubRMSE>0.058). The PS images were able to detect nearly 95% of the WBs, whereas Landsat was able to identify only 32% at the water fraction threshold >40%. Initial results from this study show that the high spatial and temporal resolution PS datasets show promise in monitoring WBs in arid regions of West Africa.     

增强地图服务,做大地理信息板块

回顾了北京市测绘设计研究院二十多年地理信息产业的发展历史,分析了所面临的机遇与挑战,认为空间数据的可视化输出-地图生产是地理信息产业的主要任务之一。搞好这项工作应建立GIS数据库到地图数据库的双向通道;扩展地图数据库的地图制图和桌面出版功能;编制好系列基础底图和社会公众普遍需要的普通地图、政区图、地名图、交通旅游图,逐步实现编制导航地图,争取导航电子地图资质;做好用户需求调查,编制若干专题地图产品;开发影像地图、三维地图、实景地图等地理信息新品种;跟踪国家开展的各类普查或调查项目,编制高科技含量的地图集。