David J. Coleman

Towards Web-based representation and processing of health information

BackgroundThere is great concern within health surveillance, on how to grapple with environmental degradation, rapid urbanization, population mobility and growth. The Internet has emerged as an efficient way to share health information, enabling users to access and understand data at their fingertips. Increasingly complex problems in the health field require increasingly sophisticated computer software, distributed computing power, and standardized data sharing. To address this need, Web-based mapping is now emerging as an important tool to enable health practitioners, policy makers, and the public to understand spatial health risks, population health trends and vulnerabilities. Today several web-based health applications generate dynamic maps; however, for people to fully interpret the maps they need data source description and the method used in the data analysis or statistical modeling. For the representation of health information through Web-mapping applications, there still lacks a standard format to accommodate all fixed (such as location) and variable (such as age, gender, health outcome, etc) indicators in the representation of health information. Furthermore, net-centric computing has not been adequately applied to support flexible health data processing and mapping online.ResultsThe authors of this study designed a HEalth Representation XML (HERXML) schema that consists of the semantic (e.g., health activity description, the data sources description, the statistical methodology used for analysis), geometric, and cartographical representations of health data. A case study has been carried on the development of web application and services within the Canadian Geospatial Data Infrastructure (CGDI) framework for community health programs of the New Brunswick Lung Association. This study facilitated the online processing, mapping and sharing of health information, with the use of HERXML and Open Geospatial Consortium (OGC) services. It brought a new solution in better health data representation and initial exploration of the Web-based processing of health information.ConclusionThe designed HERXML has been proven to be an appropriate solution in supporting the Web representation of health information. It can be used by health practitioners, policy makers, and the public in disease etiology, health planning, health resource management, health promotion and health education. The utilization of Web-based processing services in this study provides a flexible way for users to select and use certain processing functions for health data processing and mapping via the Web. This research provides easy access to geospatial and health data in understanding the trends of diseases, and promotes the growth and enrichment of the CGDI in the public health sector.

A semi-automated approach for extracting buildings from QuickBird imagery applied to informal settlement mapping

Recent advances in sensor technology have promoted the mapping communities to investigate the potential and information contents of recent very high‐resolution satellite images. In this paper, we report our new semi‐automatic building extraction approach and our first results of mapping informal settlement areas obtained using QuickBird high‐resolution images. We implemented our mapping approach using snakes and a radial casting algorithm, and assessed the results both qualitatively and quantitatively and compared them with ground truth data from a similar area. Finally, we summarized the potential and limitations of the second‐generation commercial high‐resolution satellite images to extract buildings using existing software.

Potential Contributions and Challenges of VGI for Conventional Topographic Base-Mapping Programs

This chapter introduces the context and characteristics implicit in conventional digital topographic mapping programs and then contrasts them to important underlying assumptions regarding volunteered geographic information. It defines the term “authoritative data” and challenges its use in the context of comprehensive topographic base-mapping programs. After examining prevailing cultures and assumptions that must be adjusted and workflows that must be modified to manage risk and make the best use of VGI in this role, case studies from the state of Victoria, Australia; the United States Geological Survey; and TomTom describe the early experiences of conventional mapping organizations in this regard. The author contends that VGI is not the ultimate solution to all geospatial data updating and maintenance challenges now faced by mapping organizations. However, it does represent an important potential channel of such updates that needs to be investigated seriously and implemented responsibly.

Citizen Surveillance of the State: A Mirror for eGovernment?

This paper discusses, conceptually and empirically, the role of geographic ICT (geoICT) and virtual globes (e.g. Google Earth) at the interface of public policy and citizens. Our preliminary findings from on-going field work in an Indian city and in Zanzibar suggest that virtual globe technology can potentially transfer to citizens surveillance power, traditionally held by the government. Starting from the traditional electronic government framework, where bureaucracy acts as a filter between policy makers and citizens with grievances, we outline an emerging framework where commercial virtual globes act as mediators between policy-makers and citizens. We show that the emerging framework holds the potential of allowing citizens concerned, in our case, about the quality of water services, to influence policy makers directly. The virtual globe acts as a mirror to the traditional eGovernment framework and lends a different societal visibility both to public services provision, and to localized citizens’ needs.

Developing a groupware-based prototype to support geomatics production management

Abstract Digital map and chart providers are under increasing pressure to bring their original and updated products to market in shorter time frames than ever before. As the contract production model has come to play an increasingly significant role in digital mapping and charting programs, workflow processes and production tasks have at least been extended, if not redefined. At the same time, through the refinement and integration of groupware tools and Intranet/Extranet software, applications of computer-supported cooperative work have emerged in support of both project-driven research and corporate information management. The Geographical Engineering Group at University of New Brunswick has undertaken a program of research to: (1) investigate the applicability of groupware and database technologies to support collaborative geomatics production in networked environments; (2) develop Extranet-based prototypes; and (3) evaluate the effects of these prototypes on project management and organizational culture. A summary of the results from the preliminary works is presented in this paper. Focus has been placed on the collaboration prototype developed in terms of quality control inspection project in mapping and charting productions. The paper concludes with a discussion of key design and implementation issues.

Modeling distributed GIS data production workflow

Real-time access to status of project progress, control of production processes and activities, and automation of production procedures are major hurdles in further improving production throughput and project management in distributed GIS data production projects. Workflow technology promises to address these issues by facilitating, automating or controlling GIS data production processes. The success of applying workflow technologies to distributed GIS data production requires comprehensive understanding of the underlying production processes. This paper presents the first research effort on rigorously modeling distributed GIS data production workflows, with particular attention to a GIS data quality control process using the Internet-based workflow management technologies. Existing practices of distributed GIS data production projects are used as the essential sources for modeling the required workflow. The paper discusses some issues faced and concepts such as workflow process repository and GIS data QC testing program repository.

Semi-automatic building extraction in dense urban settlement areas from high-resolution satellite images

Abstract Recent availability of high-resolution satellite images provides a new data source for geospatial data acquisition. This high-resolution data source has made it possible to extract man-made features such as roads and buildings, which are required for varieties of applications including urban planning, creation of GIS databases, and environmental monitoring. In this paper, we have developed a new method to extract buildings in urban informal settlement areas using high-spatial resolution panchromatic imagery. The proposed method uses radial casting algorithm to initialize snakes contours, and the fine measurement of building outlines is automatically carried out using snakes models. The building extraction results are satisfactory with an extraction rate of 94 percent as demonstrated by examples over a variety of selected test areas. The potential and limitations of applying this method to extract buildings is also discussed.

The Potential for Using Very High Spatial Resolution Imagery for Marine Search and Rescue Surveillance

Abstract Recreational boating activities represent one of the highest risk populations in the marine environment. Moreover, there is a trend of increased risk exposure by recreational boaters such as those who undertake adventure tourism, sport fishing/hunting, and personal watercraft (PWC) activities. When trying to plan search and rescue activities, there are data deficiencies regarding inventories, activity type, and spatial location of small, recreational boats. This paper examines the current body of research in the application of remote sensing technology in marine search and rescue. The research suggests commercially available very high spatial resolution satellite (VHSR) imagery can be used to detect small recreational vessels using a sub‐pixel detection methodology. The sub‐pixel detection method utilizes local image statistics based on spatio‐spectral considerations. This methodology would have to be adapted for use with VHSR imagery as it was originally used in hyperspectral imaging. Further, the authors examine previous research on ‘target characterization’ which uses a combination of spectral based classification, and context based feature extraction to generate information such as: length, heading, position, and material of construction for target vessels. This technique is based on pixel‐based processing used in generic digital image processing and computer vision. Finally, a preliminary recreational vessel surveillance system ‐ called Marine Recreational Vessel Reconnaissance (MRV Recon) is tested on some modified VHSR imagery.

An enhanced spatio-spectral template for automatic small recreational vessel detection

This paper examines the performance of a spatiospectral template on Ikonos imagery to automatically detect small recreational boats. The spatiospectral template is utilized and then enhanced through the use of a weighted Euclidean distance metric adapted from the Mahalanobis distance metric. The aim is to assist the Canadian Coast Guard in gathering data on recreational boating for the modeling of search and rescue incidence risk. To test the detection accuracy of the enhanced spatiospectral template, a dataset was created by gathering position and attribute data for 53 recreational vessel targets purposely moored for this research within Cadboro Bay, British Columbia, Canada. The Cadboro Bay study site containing the targets was imaged using Ikonos. Overall detection accuracy was 77%. Targets were broken down into 2 categories: 1) Category A-less than 6 m in length, and Category B-more than 6 m long. The detection rate for Category B targets was 100%, while the detection rate for Category A targets was 61%. It is important to note that some Category A targets were intentionally selected for their small size to test the detection limits of the enhanced spatiospectral template. The smallest target detected was 2.2 m long and 1.1 m wide. The analysis also revealed that the ability to detect targets between 2.2 and 6 m long was diminished if the target was dark in color.

The Canadian Surveying and Mapping Industry in 1987

Abstract A countrys economic and social development is shaped in large measure not only by its distinctive physical and economic geography, but also by how this geography is perceived by its people and leaders. Knowledge about the physical character and natural resources of a country is of fundamental importance in undertaking any development strategy and this information is largely derived from surveys, maps and charts. From a Canadian perspective, Dr. E.F. Roots has noted that because “Canada was a large land with comparatively few native inhabitants, and because its modern settlement took place rapidly in the wake of the industrial revolution and the first organised applications of technology to country development, surveys and mapping have played a perhaps more important and familiar role in the development of the country than in most other nations. Cadastral, boundary and resource surveys have to a large degree led the development of Canada, rather than followed it.” [Roots, 1985] And, almost from t...