基于Android的城市空气质量查询系统的设计与实现

为了方便公众第一时间了解和掌握空气质量状况及变化情况,设计并实现了基于Android平台的城市空气质量查询系统。该系统通过HTML解析,获取了来自中国环境监测总站发布的114个监测城市的实时数据。系统使用Android最新ActionBar样式的导航界面以及直观的仪表界面,实现了各城市空气质量指数查询、空气质量排名查询、各监测点数据查询、一周数据查询等功能。经试用,该系统在Android手机上运行良好。     

基于MMS和Web GIS的移动搜索

针对目前WAP带宽瓶颈和高额付费问题,提出一种将MMS和Web GIS相结合的移动搜索设计方案。以Web GIS作为空间信息引擎,采用MMS7.0和CMPP3.0为通信协议,依托Lucene技术框架实现中文索引和分词,搭建移动空间信息搜索平台。该平台接受移动用户查询,并生成空间信息,以彩信方式反馈到手机用户。实验结果证明,该方案可以有效降低移动搜索成本。     

基于.NET的考古遗址空间信息系统的设计与实现

为实现考古遗址空间信息的开放式管理和可视化查询功能,提出一种基于XML和MapInfo技术的解决方案,并在.NET平台下设计实现了一个考古遗址空间信息系统ASIS.在阐述了该系统的设计思路和实现技术的基础上,提出将页面控件的属性取值映射到XML模板文件的属性位置,再将XML模板文件解析后保存在属性数据表中的方法,实现了开放式的遗址属性信息管理;提出利用图元将遗址空间信息与属性信息关联,在关系数据库上实现了对遗址空间信息的可视化查询.通过原型系统的运行,验证了所提方法的可行性和实用性.     

面向数字校园的网格LBS体系构架研究

为了有效解决基于位置的服务（LBS）系统中空间信息的共享问题,提出了面向网格计算环境下空间信息网格的数据组织与访问机制模型,构建了以服务为核心,包括定位层、数据层、服务层和应用层的基于网格地理信息系统的校园LBS（CLGG）体系构架。以数字校园为应用实例,研制了原型系统, 实现了的区域导航、实时定位、历史路径查询、热点区域信息发布、用户认证与管理等功能,验证了所提出的LBS系统构架和空间信息网格的数据组织与访问机制的可行性和有效性。     

空间信息共享平台中数据索引服务的研究*

为消除空间信息孤岛,研究开放网格服务架构,建立空间信息共享平台。用户通过平台中的网格服务透明访问虚拟组织中的数据。为提升数据索引服务的性能,提出一种改进的R树算法,在节点分裂时考虑其他节点是否有剩余空间,从而避免了频繁的分裂导致产生大量的节点。实验结果表明,与经典R-树节点分裂算法相比,改进后的节点分裂算法的空间查询性能得到提升,该研究可为空间信息全面共享提供实用可行的实施方案。     

基于Android平台的车载导航系统的研究与设计

为缩短嵌入式车载导航系统开发进程,提高系统维护和升级能力,研究了Android平台的特点以及车载导航系统的性能需求,提出在andriod平台基础上,结合baidu map,设计一个基于Android平台的车载导航终端系统;实验结果表明,该系统实现了车辆自我定位、地图查询、路径规划和导航;经过严格测试,系统运行良好.     

房地产信息管理系统开发研究

根据房地产信息的基本特征,研究了房地产信息管理系统的数据结构和系统功能,结合某部队的房地产信息普查,在地理信息系统平台下研制了部队房地产信息管理系统。该系统具有空间数据管理的特性、对象的空间分布查询、条件查询和专题查询等功能。此外充分利用空间信息实现了图文互访查询和图上全景图像的浏览。以图、表、文相结合,全面地表述房地产信息,大幅度地提高了房地产管理的水平和效率。     

基于OGC规范和Open Source项目的WebGIS开发与应用

为更好地实现地理空间信息共享,在最新开源（Open Source）项目基础上,设计与开发一个基于OGC标准规范的WebGIS空间数据管理系统,给出具体的实现步骤。该方案可高效地完成矢量空间信息的入库、地图发布、可视化浏览、空间目标对象属性信息查询等任务,能够为集成应用提供标准的数据访问和获取接口。最后,将其应用到国家科技基础条件平台“地球系统科学数据共享平台”中,取得较好效果。     

多功能话务服务系统技术解决方案

为了提高服务质量和效率,针对普通114查号系统不能更好地满足多功能号码查询服务需求的问题,提出了一套完整的电话号码查询人工处理系统。通过采用开放式的、面向组件的多层Client/Server系统结构,构建了一个多种功能的系统平台。应用结果表明,多功能话务服务系统号码查询效率提高了40%;在数据管理、排队管理方面居于同行业领先水平。     

一种空间信息网格平台的设计与实现

网格技术的出现为空间信息科学的发展带来了新的机遇,如何把网格技术有效的融入到空间信息的处理和应用中正是空间信息网格要解决的问题。建立空间信息网格应用项目首先要选择好网格基础平台,本文首先介绍了当前常用的几种网格平台的特点及适用领域,接着阐述了开发一套空间信息网格平台的必要性,之后详细介绍了空间信息网格(SIG,Spatial Information Grid)平台的设计与实现,最后讲述了平台的安装及运行结果。     

A novel visualization model for web search results

This paper presents an interactive visualization system, named WebSearchViz, for visualizing the Web search results and acilitating users' navigation and exploration. The metaphor in our model is the solar system with its planets and asteroids revolving around the sun. Location, color, movement, and spatial distance of objects in the visual space are used to represent the semantic relationships between a query and relevant Web pages. Especially, the movement of objects and their speeds add a new dimension to the visual space, illustrating the degree of relevance among a query and Web search results in the context of users' subjects of interest. By interacting with the visual space, users are able to observe the semantic relevance between a query and a resulting Web page with respect to their subjects of interest, context information, or concern. Users' subjects of interest can be dynamically changed, redefined, added, or deleted from the visual space.     

iNavigation: an image based indoor navigation system

This paper presents a novel image-based indoor navigation web application designed for mobile phone. It is inspired by Google Street View that features 360° imagery for navigation. Ordinary data collection of image based navigation systems implements panorama cameras, so it is difficult to be extended to indoor environment. On the other hand, they cannot provide timely updates because it requires immense image data. This paper introduces a ‘proof of concept’ which only uses ordinary organized photo collections instead of panoramic photo to guide people through the building. It implements SIFT (scale-invariant feature transform) feature detection and ANN (approximately nearest neighbor) search to provide positioning service. People can upload query images to obtain current position. It also enables information sharing by using IPM (inverse perspective mapping) technique to figure out distance from a single query image, and update the query image into the image collection correctly based on the distance calculation.     

Join index hierarchy: an indexing structure for efficientnavigation in object-oriented databases

A novel indexing structure-the join index hierarchy-is proposed to handle the “gotos on disk” problem in object-oriented query processing. The method constructs a hierarchy of join indices and transforms a sequence of pointer-chasing operations into a simple search in an appropriate join index file, and thus accelerates navigation in object-oriented databases. The method extends the join index structure studied in relational and spatial databases, supports both forward and backward navigation among objects and classes, and localizes update propagations in the hierarchy. Our performance study shows that a partial join index hierarchy outperforms several other indexing mechanisms in object-oriented query processing     

空间元数据研究及应用

分布式地理空间数据的快速导航一直是分布式GIS研究的重点。针对地理空间数据的特点,在已有空间元数据标准的基础上,构造了一个分层空间元数据库框架,设计实现了不同级别的空间元数据库,很好地组织和管理了分布在网络上的地理空间数据库及其数据;在分层空间元数据库的支持下,基于地图（图层）的4个基本要素（专题、空间范围、地层、时间）,设计了一个面向用户的地理空间数据请求描述规范,并据此实现了一个基于多Agent的分布工地理空间数据查找策略,该策略能够很好地确定性或非确定性地理空间数据快速导航的要求。     

利用TreeView实现层次结构数据导航查询

为了充分发挥TreeView控件展示数据和导航查询的作用,通过一个通讯录实例,介绍了如何在ADO.NET中利用TreeView实现层次结构数据的加载及导航查询,讨论了如何做到精准导航查询。提出了改进的导航查询方案中的自定义函数,具有一定的借鉴意义。     

Location-aware query reformulation for search engines

Query reformulation, including query recommendation and query auto-completion, is a popular add-on feature of search engines, which provide related and helpful reformulations of a keyword query. Due to the dropping prices of smartphones and the increasing coverage and bandwidth of mobile networks, a large percentage of search engine queries are issued from mobile devices. This makes it possible to improve the quality of query recommendation and auto-completion by considering the physical locations of the query issuers. However, limited research has been done on location-aware query reformulation for search engines. In this paper, we propose an effective spatial proximity measure between a query issuer and a query with a location distribution obtained from its clicked URLs in the query history. Based on this, we extend popular query recommendation and auto-completion approaches to our location-aware setting, which suggest query reformulations that are semantically relevant to the original query and give results that are spatially close to the query issuer. In addition, we extend the bookmark coloring algorithm for graph proximity search to support our proposed query recommendation approaches online, and we adapt an A* search algorithm to support our query auto-completion approach. We also propose a spatial partitioning based approximation that accelerates the computation of our proposed spatial proximity. We conduct experiments using a real query log, which show that our proposed approaches significantly outperform previous work in terms of quality, and they can be efficiently applied online.     

基于Lucene的语义检索系统

在一种基于LUCENE的传统文本检索引擎之上,采用C/S架构模式的语义检索实验系统。用户可以根据需要,从客户端向服务器提交相应的查询信息配置,服务器根据此配置,通过本体导航与同义词查询2种查询扩展优化技术,对提交的查询关键词组进行查询、扩展等优化处理后,将经优化处理过的查询关键词组导入传统的文本检索引擎中,对文档资源进行匹配,将查询结果根据用户要求的排列,并依次返回给用户。通过用户与服务器的信息交互与对查询语句的查询扩展,该系统提高了查准率与查全率。     

Analysis of navigation behaviour in web sites integrating multiple information systems

Abstract. The analysis of web usage has mostly focused on sites composed of conventional static pages. However, huge amounts of information available in the web come from databases or other data collections and are presented to the users in the form of dynamically generated pages. The query interfaces of such sites allow the specification of many search criteria. Their generated results support navigation to pages of results combining cross-linked data from many sources. For the analysis of visitor navigation behaviour in such web sites, we propose the web usage miner (WUM), which discovers navigation patterns subject to advanced statistical and structural constraints. Since our objective is the discovery of interesting navigation patterns, we do not focus on accesses to individual pages. Instead, we construct conceptual hierarchies that reflect the query capabilities used in the production of those pages. Our experiments with a real web site that integrates data from multiple databases, the German SchulWeb, demonstrate the appropriateness of WUM in discovering navigation patterns and show how those discoveries can help in assessing and improving the quality of the site. Received June 21, 1999 / Accepted December 24, 1999     

Orchard: Exploring Multivariate Heterogeneous Networks on Mobile Phones

People are becoming increasingly sophisticated in their ability to navigate information spaces using search, hyperlinks, and visualization. But, mobile phones preclude the use of multiple coordinated views that have proven effective in the desktop environment (e.g., for business intelligence or visual analytics). In this work, we propose to model information as multivariate heterogeneous networks to enable greater analytic expression for a range of sensemaking tasks while suggesting a new, list-based paradigm with gestural navigation of structured information spaces on mobile phones. We also present a mobile application, called Orchard, which combines ideas from both faceted search and interactive network exploration in a visual query language to allow users to collect facets of interest during exploratory navigation. Our study showed that users could collect and combine these facets with Orchard, specifying network queries and projections that would only have been possible previously using complex data tools or custom data science.     

Search on transportation networks for location-based service

The issue of how to provide location-based service (LBS) attracted many researchers. In this paper, we focus on a typical situation of LBS which is to provide services for users in cars that move in a road network. To provide such kind of services, an integration method for representing transportation information with a road map is proposed. By using our integration method, since the transportation information of road networks is managed under the spatial index structure created for road networks, spatial queries on them can take advantages of the spatial index structure and achieve an efficient process. Moreover, we discuss path search, region search, nearest neighbor search and continuous nearest neighbor search in this paper, which are based on transportation networks with (or without) considering the static spatial objects outside the transportation networks. Using transportation information and the corresponding real road network, the paper offers evaluations by comparing our representation method and query method with those in related works. The results show a good performance of our methods.