首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 562 毫秒
1.
This paper adopts a Bayesian spatial modeling approach to investigate the distribution of young offender residences in York Region, Southern Ontario, Canada, at the census dissemination area level. Few geographic researches have analyzed offender (as opposed to offense) data at a large map scale (i.e., using a relatively small areal unit of analysis) to minimize aggregation effects. Providing context is the social disorganization theory, which hypothesizes that areas with economic deprivation, high population turnover, and high ethnic heterogeneity exhibit social disorganization and are expected to facilitate higher instances of young offenders. Non-spatial and spatial Poisson models indicate that spatial methods are superior to non-spatial models with respect to model fit and that index of ethnic heterogeneity, residential mobility (1 year moving rate), and percentage of residents receiving government transfer payments are, respectively, the most significant explanatory variables related to young offender location. These findings provide overwhelming support for social disorganization theory as it applies to offender location in York Region, Ontario. Targeting areas where prevalence of young offenders could or could not be explained by social disorganization through decomposing the estimated risk map are helpful for dealing with juvenile offenders in the region. Results prompt discussion into geographically targeted police services and young offender placement pertaining to risk of recidivism. We discuss possible reasons for differences and similarities between the previous findings (that analyzed offense data and/or were conducted at a smaller map scale) and our findings, limitations of our study, and practical outcomes of this research from a law enforcement perspective.  相似文献   

2.
随着城市建设的发展和环保建设研究的不断增强,防尘、噪声等污染正在严重影响城市环保绿色建设,同时,工地的安全、文明施工也逐渐成为现代工地的必备条件之一。大型工地的智慧化监管越来越智能化。本文以“智慧工地”建设为目标,引入地理信息技术和物联网技术,将工地位置和实时监测数据融合在一起,同时配合视频监控和GPS车辆定位等,建立初步的智慧工地综合监管平台,为文明施工和文明执法提供依据。此平台在工地应用,提供实时报警和设备联动,提升了自动化水平和安全水平,保障了工地施工的文明和安全。  相似文献   

3.
The representation of place is a key theoretical advancement that geographic information science can offer to improve the understanding of environmental determinants of health, but developing robust computational representations of place requires a substantial departure from conventional notions of geographic representation in GIS. Unlike conventional GIS representations based on either objects or locations, we suggest that place representation should incorporate dynamic subjective, experiential, and relational aspects of place, as the influence of place on health behavior concerns not only the features that can be objectively observed at a particular location but also the environmental perceptions of the individual, as molded by biological, social, and experiential characteristics. In addition, assessments of environmental exposures on health outcomes should focus on individuals' time–activity patterns and microenvironment profiles, which form a potentially unique personalized exposure environment for each individual. Addressing these representational challenges via collaborative research has the potential to advance both geographic information science and health research.  相似文献   

4.
In human cognition, both visual features (i.e., spectrum, geometry and texture) and relational contexts (i.e. spatial relations) are used to interpret very-high-resolution (VHR) images. However, most existing classification methods only consider visual features, thus classification performances are susceptible to the confusion of visual features and the complexity of geographic objects in VHR images. On the contrary, relational contexts between geographic objects are some kinds of spatial knowledge, thus they can help to correct initial classification errors in a classification post-processing. This study presents the models for formalizing relational contexts, including relative relations (like alongness, betweeness, among, and surrounding), direction relation (azimuth) and their combination. The formalized relational contexts were further used to define locally contextual regions to identify those objects that should be reclassified in a post-classification process and to improve the results of an initial classification. The experimental results demonstrate that the relational contexts can significantly improve the accuracies of buildings, water, trees, roads, other surfaces and shadows. The relational contexts as well as their combinations can be regarded as a contribution to post-processing classification techniques in GEOBIA framework, and help to recognize image objects that cannot be distinguished in an initial classification.  相似文献   

5.
Representing Complex Geographic Phenomena in GIS   总被引:1,自引:0,他引:1  
Conventionally, spatial data models have been designed according to object- or field-based conceptualizations of reality. Conceptualization of complex geographic phenomena that have both object- and field-like properties, such as wildfire and precipitation, has not yet been incorporated into GIS data models. To this end, a new conceptual framework is proposed in this research for organizing data about such complex geographic phenomena in a GIS as a hierarchy of events, processes, and states. In this framework, discrete objects are used to show how events and processes progress in space and time, and fields are used to model how states of geographic themes vary in a space-time frame. Precipitation is used to demonstrate the construction and application of the proposed framework with digital precipitation data from April 15 to May 22, 1998, for the state of Oklahoma, U.S.A. With the proposed framework, two sets of algorithms have been developed. One set automatically assembles precipitation events and processes from the data and stores the precipitation data in the hierarchy of events, processes, and states, so that attributes about events, processes, and states are readily available for information query. The other set of algorithms computes information about the spatio-temporal behavior and interaction of events and processes. The proposed approach greatly enhances support for complex spatio-temporal queries on the behavior and relationships of events and processes.  相似文献   

6.
随着城市建设和发展,违法用地和违法建设现象愈演愈烈,制止“两违”是一项长期复杂的工作。一直以来,“两违”执法程序烦琐,缺乏有效的技术手段,无法及时发现和制止违法行为。利用遥感(RS)技术可以实时监测土地违法现象,结合地理信息系统(GIS)和全球定位系统(GPS)技术构建“两违”执法管理平台,能准确快速地定位“两违”图斑并指导现场执法巡查。本文以石狮市为例,研究了3S(RS、GIS、GPS,遥感(Rernote Sensing,RS)、地理信息系统(Geographic Information System,GIS)、全球定位系统(Global Positioning System,GPS))技术在“两违”执法工作中的实践应用。结果表明,“3S”技术可以全面及时地发现土地违法行为,极大地提高执法效率。  相似文献   

7.
The use of object-orientation for both spatial data and spatial process models facilitates their integration, which can allow exploration and explanation of spatial-temporal phenomena. In order to better understand how tight coupling might proceed and to evaluate the possible functional and efficiency gains from such a tight coupling, we identify four key relationships affecting how geographic data (fields and objects) and agent-based process models can interact: identity, causal, temporal and topological. We discuss approaches to implementing tight integration, focusing on a middleware approach that links existing GIS and ABM development platforms, and illustrate the need and approaches with example agent-based models.  相似文献   

8.
贾奋励  张威巍  游雄 《遥感学报》2015,19(2):179-187
作为新一代地理分析工具,虚拟地理环境对于增强人类地理认知、分析解决地理问题方面具有显著优势。目前虚拟地理环境的基本框架、实现技术均有较多论述与成果。但在虚拟地理环境的认知研究方面尚缺乏有效指导。为提高虚拟地理环境构建的科学性,本文通过对虚拟地理环境现有概念的分析,提出从系统论角度进行虚拟地理环境认知研究的观点;并对虚拟地理环境的认知与地理认知、地图认知等相近概念进行了对比分析。从现实环境与虚拟环境间的相似性入手建立了虚拟地理环境的认知研究框架,该框架从思维相似、感觉相似、几何相似、特性相似和离散相似5个方面探讨了虚拟地理环境认知研究目前的着眼点,并将思维相似作为虚拟地理环境认知研究的重点与难点。该框架将虚拟地理环境的认知问题置于一个更广泛背景中进行研究,一方面体现了虚拟地理环境所具有的地理实验研究新平台的作用,另一方面重点强调了人的作用,对深入开展虚拟地理环境的研究具有重要意义。  相似文献   

9.
在国土资源执法监察信息化建设的背景下,通过对市、县级国土资源执法监察业务的分析与梳理,构建了动态巡查和卫片执法监察的业务模型和业务流程,完成了移动执法监察管理信息系统的设计与开发。本文对系统的总体架构、系统功能、系统特点和应用情况作了简要介绍。  相似文献   

10.
基于粗集的环境机制发现模型及其渔业应用   总被引:3,自引:0,他引:3  
地学事件或地学变量受控于环境因子,其关系常为非线性。另一方面,影响变量取值或事件发生的时空范围及其环境要素具有不确定性。环境因子的时空配置关系集中体现这种关系的复杂度。这使得寻找决定事件发生或某些地学变量取值的环境因子及其组合存在困难。针对渔场形成的环境机制发现,构建RS-STAMM模型,将时空离散化,以邻域方法提取空间环境变量,形成决策表,利用粗集约简方法,对环境因子及其时空配置关系进行筛选,进而寻找影响事件或变量取值的环境因子的时空配置结构。最后以发现渔场形成的环境机制为目标,将模型应用在渔业遥感研究中,以海洋鱼类聚集的温度场配置提取为实例,验证模型有效性。  相似文献   

11.
闾国年  袁林旺  俞肇元 《测绘学报》2017,46(10):1549-1556
系统回顾了地理信息系统产生以来地理信息内涵发展与拓展的主要历程,指出地理信息的定义一直是在"空间+属性"的地图信息基本框架下逐步扩展,其发展历程经历了地图GIS、语义GIS、时空GIS和大数据GIS 4个不同的阶段,但仍无法满足时空大数据的分析和应用需求。从地理学研究的对象和内容出发,对地理学所需要的"地理信息"的内涵和外延进行了系统的梳理总结,提出了涵盖"空间定位""语义描述""属性特征""几何形态""演化过程""要素相互关系"的地理信息六要素表达模型。在地理定律和地理规律的指导下,面向地理现象空间分布、时空格局、演化过程、相互作用机理的集成表达、系统分析和高效管理,设计了六要素集成表达的几何代数统一GIS数据模型、地理规律与相互作用驱动的新型GIS数据结构、非结构化时空数据组织与存储等关键技术,为测绘地理信息走向地理科学信息提供了另一个理论基础与技术方法支撑,有助于提升GIS对地理格局、演化过程和要素相互作用等地理规律的组织、管理、表达和分析能力。  相似文献   

12.
以HJ-1A/B或北京一号卫星多光谱数据为数据源,采用遥感技术、地理信息系统技术及计算机技术等高新技术手段,开展了2009~2010年甘肃省新增机场、港口码头、高尔夫球场大宗用地的监测,及时、准确地掌握该地区土地利用情况,为土地督察、执法提供确实可靠的资料.  相似文献   

13.
Learning knowledge graph (KG) embeddings is an emerging technique for a variety of downstream tasks such as summarization, link prediction, information retrieval, and question answering. However, most existing KG embedding models neglect space and, therefore, do not perform well when applied to (geo)spatial data and tasks. Most models that do consider space primarily rely on some notions of distance. These models suffer from higher computational complexity during training while still losing information beyond the relative distance between entities. In this work, we propose a location‐aware KG embedding model called SE‐KGE. It directly encodes spatial information such as point coordinates or bounding boxes of geographic entities into the KG embedding space. The resulting model is capable of handling different types of spatial reasoning. We also construct a geographic knowledge graph as well as a set of geographic query–answer pairs called DBGeo to evaluate the performance of SE‐KGE in comparison to multiple baselines. Evaluation results show that SE‐KGE outperforms these baselines on the DBGeo data set for the geographic logic query answering task. This demonstrates the effectiveness of our spatially‐explicit model and the importance of considering the scale of different geographic entities. Finally, we introduce a novel downstream task called spatial semantic lifting which links an arbitrary location in the study area to entities in the KG via some relations. Evaluation on DBGeo shows that our model outperforms the baseline by a substantial margin.  相似文献   

14.
作为空间数据质量的重要方面,一致性关系维护在多源数据集成建库与一致性更新中扮演重要角色。相较于同一要素类目标间发生的拓扑不一致,不同要素类目标间的不一致问题通常表现为深层次的分布模式不匹配,语义关系逻辑矛盾等,实施一致性维护困难得多。本研究从地理学第一定律出发,将不同性质地理实体空间分布上形成的依存关系作为一致性评价的依据。首先,总结归纳了位置共享、结构关联、区域包含3种不同类型的分布依存关系,并形式化表达为一致性约束规则;然后,探讨了违背不同类型约束规则的冲突现象探测与一致性改正方法。本研究从地理学角度认知空间数据质量问题,通过知识工程手段,引入分布依存知识作为一致性处理的依据,对扩宽空间数据质量的研究思路具有意义。  相似文献   

15.
陈琦 《北京测绘》2012,(4):52-54
为确保土地违法用地案件早发现、早制止、早报告,本文利用ESRI公司开发的ArcGIS9.3.1软件为地理信息数据管理平台,结合GIS、RS和GPS技术,建立土地执法监察辅助应用系统,形成土地执法监察新机制,帮助土地执法监察工作人员快速准确发现疑似违法用地的位置,方便数据统计和上报。  相似文献   

16.
t-GIS and environmental dynamic models   总被引:2,自引:0,他引:2  
1 IntroductionTodayitseemsthatpeople’sinterestandatten tiontoGISmainlyfocusontheaspectofspatialat tributesofgeographicinformation ,notsufficientlyontimefactor .Thisisanerroneoustendency ,anditwillbedisadvantageoustothebalanceddevelop mentofGISwhenexplaini…  相似文献   

17.
地理可达性是研究评价各种服务设施布局及其服务域的重要指标之一,空间距离、交通便捷性、出行成本等是可达性测度的重要因子。由于医疗设施等公共设施通常以服务的公平性和覆盖性为目标,因此可定义居民点到最邻近医院的距离为地理可达性的测度。在此基础上,作者提出了基于GIS与Voronoi多边形的地理可达性计算方法。这一方法不仅将地理可达性分析中的空间点对之间的距离计算简化为空间查询,方便了GIS应用,而且计算的Voronoi多边形在本质上就是最邻近意义上医院的服务域,即服务域内各居民点到该医院的距离就是最邻近距离。此外结合人口分布等属性数据,还可深入分析各医院的服务承载力,本方法为医疗设施等公共服务设施的规划决策提供了重要的工具。  相似文献   

18.
Dynamic flood disaster simulation is an emerging and promising technology significantly useful in urban planning, risk assessment, and integrated decision support systems. It is still an important issue to integrate the large assets such as dynamic observational data, numerical flood simulation models, geographic information technologies, and computing resources into a unified framework. For the intended end user, it is also a holistic solution to create computer interpretable representations and gain insightful understanding of the dynamic disaster processes, the complex impacts, and interactions of disaster factors. In particular, it is still difficult to access and join harmonized data, processing algorithms, and models that are provided by different environmental information infrastructures. In this paper, we demonstrate a virtual geographic environments-based integrated environmental simulation framework for flood disaster management based on the notion of interlinked resources, which is capable of automated accumulating and manipulating of sensor data, creating dynamic geo-analysis and three-dimensional visualizations of ongoing geo-process, and updating the contents of simulation models representing the real environment. The prototype system is evaluated by applying it as a proof of concept to integrate in situ weather observations, numerical weather and flood disaster simulation models, visualization, and analysis of the real time flood event. Case applications indicate that the developed framework can be adopted for use by decision-makers for short-term planning and control since the resulting simulation and visualization are completely based on the latest status of environment.  相似文献   

19.
矢量GIS空间方向关系的演算模型   总被引:5,自引:0,他引:5  
邓敏  刘文宝  李俊杰  孙电 《遥感学报》2006,10(6):821-828
空间方向关系是描述空间目标间位置分布的一类基本空间约束,在GIS中是由形式化模型描述的。但现有模型由于简化假设过多,其描述分辨率较低。以点/点空间方向关系的计算量为基础,在综合考虑空间目标的几何构成和分布关系后,提出了定量化演算空间方向关系的一种新模型。利用该模型的结果,根据定量表达与定性描述之间的转换函数,可以得到相应的定性描述结果。理论分析和算例表明,新模型对目标间距离和目标本身的形状等影响方向关系的参数更为敏感,因而比现有模型有更高的描述分辨率。  相似文献   

20.
基于GIS的"数字社区"建设技术研究   总被引:2,自引:0,他引:2  
对"数字社区"建设的相关环节和技术问题进行了研究。首先就"数字社区"建设中的应用对象进行了分析,总结出了"数字社区"的5类应用对象。从地理信息技术角度和应用的空间位置角度出发,对社区信息资源进行了分类,对社区信息资源的调查、管理,以及"数字社区"应用系统的架构提出了技术要求。对"数字社区"具体的服务功能做了分析。为基于GIS的"数字社区"建设提供了有益的借鉴和建议。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号