28,147 research outputs found
Monitoring land use changes using geo-information : possibilities, methods and adapted techniques
Monitoring land use with geographical databases is widely used in decision-making. This report presents the possibilities, methods and adapted techniques using geo-information in monitoring land use changes. The municipality of Soest was chosen as study area and three national land use databases, viz. Top10Vector, CBS land use statistics and LGN, were used. The restrictions of geo-information for monitoring land use changes are indicated. New methods and adapted techniques improve the monitoring result considerably. Providers of geo-information, however, should coordinate on update frequencies, semantic content and spatial resolution to allow better possibilities of monitoring land use by combining data sets
Review of current practices in recording road traffic incident data: with specific reference to spatial analysis and road policing policy
Road safety involves three major components: the road system, the human factor and the vehicle element.
These three elements are inter-linked through geo-referenced traffic events and provide the basis for road
safety analyses and attempts to reduce the number of road traffic incidents and improve road safety.
Although numbers of deaths and serious injuries are back to approximately the 1950s levels when there
were many fewer vehicles on the road, there are still over 100 fatalities or serious injuries every day, and
this is a considerable waste of human capital. It is widely acknowledged that the location perspective is the
most suitable methodology by which to analyse different traffic events, where by in this paper, I will
concentrating on the relationship between road traffic incidents and traffic policing. Other methods include
studying road and vehicle engineering and these will be discussed later. It is worth noting here that there is
some division within the literature concerning the definitions of âaccidentâ and âincidentâ. In this paper I
will use âincidentâ because it is important to acknowledge a vast majority of âroad accidentsâ are in fact
crimes. However I will use the term âaccidentâ where it is referred to in the literature or relevant reports. It
is important to mention here that a road traffic accident can be defined as âthe product of an unwelcome
interaction between two or more moving objects, or a fixed and moving objectâ (Whitelegg 1986). Road
safety and road incident reduction relates to many other fields of activity including education, driver
training, publicity campaigns, police enforcement, road traffic policing, the court system, the National
Health Service and Vehicle engineering.
Although the subject of using GIS to analyse road traffic incidents has not received much academic
attention, it lies in the field of crime mapping which is becoming increasingly important. It is clear that
studies have been attempted to analyse road traffic incidents using GIS are increasingly sophisticated in
terms of hypotheses and statistical technique (for example see Austin, Tight and Kirby 1997). However it is
also clear that there is considerable blurring of boundaries and the analysis of road accidents sits
uncomfortably in crime mapping. This is due to four main reasons:
- Road traffic incidents are associated with road engineering, which is concerned with generic
solutions while road traffic analysis is about sensitivity to particular contexts.
- Not all road traffic incidents are crimes
- It is not just the police who have an interest in reducing road traffic incidents, other partners
include local authorities, hospitals and vehicle manufacturers
- The management of road traffic incidents is not just confined to the police
GIS has been used for over thirty years however it has only been recently been used in the field of
transportation. The field of transportation has come to embrace Geographical Information Systems as a keytechnology to support its research and operational need. The acronym GIS-T is often employed to refer to
the application and adaptation of GIS to research, planning and management in transportation. GIS-T
covers a broad arena of disciplines of which road traffic incident detection is just one theme. Others include
in vehicle navigation systems.
Initially it was only used to ask simple accident enquiries such as depicting the relative incidence of
accidents in wet weather or when there is no street lighting, or to flag high absolute or relative incidences
of accidents (see Anderson 2002). Recently however there has been increased acknowledgement that there
is a requirement to go beyond these simple questions and to extend the analyses. It has been widely claimed
by academics and the police alike that knowing where road accidents occur must lead to better road
policing, in order to ensure that road policing becomes better integrated with other policing activities. This
paper will be used to explore issues surrounding the analysis of road traffic accidents and how GIS
analysts, police and policy makers can achieve a better understanding of road traffic incidents and how to
reduce them.
For the purpose of this study I will be trying to achieve a broader overview of the aspects concerning road
accident analysis with a strong emphasis on data quality and accuracy with concern to GIS analysis. Data
quality and accuracy are seen as playing a pivotal role in the road traffic management agenda because they assist the police and Local Authorities as to the specific location whereby management can be undertaken.
Part one will consider the introduction to road incidents and their relationship with geography and spatial
analysis and how this were initially applied to locating âhotspotsâ and the more recent theory of âaccident
migrationâ. Part two will address current data issues of the UK collection procedure. This section will pay
particular reference to geo-referencing and the implication of data quality on the procedure of analysing
road incidents using GIS. Part three addresses issues surrounding the spatial analysis of road traffic
incidents, including some techniques such as spatial autocorrelation, time-space geography and the
modifiable area unit problem. Finally part four looks at the role of effective road traffic policing and how
this can be achieved due to better understanding of the theory and issues arising from analysing road traffic
incidents. It will also look at the diffusion and use of GIS within the police and local authorities
GIS Application to Support Land Administration Services in Ghana: Institutional Factors and Software Developments
In June 1999, the Ghanaian Government launched a new land policy document that sought to address some fundamental problems associated with land administration and management in the country. The document identified the weak land administration system as a particular problem and recommended the introduction of computer-aided information systems in the âlands sectorâ. In 2001, the Government made further proposals to prepare and implement a Land Administration Programme (LAP) to provide a better platform for evolving an efficient land administration that would translate the âNational Land Policyâ into action. Thus, an up-to-date land information system (LIS), supporting efficient management of land records, is to be constructed, which provides a context for the research reported in this paper. We document two aspects of our research on the adoption of GIS by the Lands Commission Secretariat (LCS) which form part of a pilot project in GIS diffusion. Part one of the paper mainly outlines the empirical results arising from fieldwork undertaken during 2001 to determine the information and GIS requirements of the LCS in relation to their routine administrative processes and to identify the critical factors that are required to ensure that any new GIS applications are successfully embraced. Part two explains the prototype software system developed using ArcView 3.2 and Access that provides the LCS with a means to automate some of the routine administrative tasks that they are required to fulfil. The software has been modified and upgraded following an initial evaluation by LCS employees also conducted as part of the fieldwork in Accra
Geographically intelligent disclosure control for flexible aggregation of census data
This paper describes a geographically intelligent approach to disclosure control for protecting flexibly aggregated census data. Increased analytical power has stimulated user demand for more detailed information for smaller geographical areas and customized boundaries. Consequently it is vital that improved methods of statistical disclosure control are developed to protect against the increased disclosure risk. Traditionally methods of statistical disclosure control have been aspatial in nature. Here we present a geographically intelligent approach that takes into account the spatial distribution of risk. We describe empirical work illustrating how the flexibility of this new method, called local density swapping, is an improved alternative to random record swapping in terms of risk-utility
Bridging the Gap Between Traditional Metadata and the Requirements of an Academic SDI for Interdisciplinary Research
Metadata has long been understood as a fundamental component of any Spatial Data Infrastructure, providing information relating to discovery, evaluation and use of
datasets and describing their quality. Having good metadata about a dataset is fundamental to using it correctly and to understanding the implications of issues such as missing data or incorrect attribution on the results obtained for any analysis carried out.
Traditionally, spatial data was created by expert users (e.g. national mapping agencies), who created metadata for the data. Increasingly, however, data used in spatial analysis comes from multiple sources and could be captured or used by nonexpert users â for example academic researchers â many of whom are from nonâGIS disciplinary backgrounds, not familiar with metadata and perhaps working in geographically dispersed teams. This paper examines the applicability of metadata in this academic context, using a multiânational coastal/environmental project as a case study. The work to date highlights a number of suggestions for good practice, issues and research questions relevant to Academic SDI, particularly given the increased levels of research data sharing and reuse required by UK and EU funders
A framework for utility data integration in the UK
In this paper we investigate various factors which prevent utility knowledge from being
fully exploited and suggest that integration techniques can be applied to improve the
quality of utility records. The paper suggests a framework which supports knowledge
and data integration. The framework supports utility integration at two levels: the
schema and data level. Schema level integration ensures that a single, integrated geospatial
data set is available for utility enquiries. Data level integration improves utility data
quality by reducing inconsistency, duplication and conflicts. Moreover, the framework
is designed to preserve autonomy and distribution of utility data. The ultimate aim of
the research is to produce an integrated representation of underground utility infrastructure
in order to gain more accurate knowledge of the buried services. It is hoped that
this approach will enable us to understand various problems associated with utility data,
and to suggest some potential techniques for resolving them
Spectral characterization of the Nigerian shoreline using Landsat imagery
The challenges of shoreline mapping include the high costs of acquiring up-to-date survey data over the coastal area. As a result, in many developing countries, the shoreline has not been consistently mapped. The variety of methods used for this mapping and the large time differences between the surveys (on the order of decades) could result in inaccuracies in shoreline data. This study presents the development of a shoreline characterization procedure for the Nigerian coastline using satellite remote sensing technology. The study goal is to produce a complete, consistent and continuous shoreline map using publicly available data processed in a GIS environment. A spectral analysis using different satellite bands was conducted to define the land/water boundary and characterize the coastal area around the shoreline. The satellite-derived shorelines were compared to charted shorelines for adequacy and consistency. The procedure was developed based on study sites along the Nigerian coastline. Although the shoreline characterization procedure is developed based on datasets from Nigeria, the procedure should be suitable for use in mapping other developing areas around world
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