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Abstract: The concept of interoperability
has been of concern to the GIS community for twenty years. In
an attempt to promote data interoperability the Open GIS Consortium
(OGC) has developed Geography Markup Language (GML), an open standard
for the description of geographical data. GML is based on Extensible
Markup Language (XML), the technology that fast become the data
exchange standard over the Internet. This research reviews the
penetration of GML in the Geographical Information (GI) industry,
and addresses the advantages and disadvantages of adopting GML
as an industry data standard. Various case studies focusing on
the benefits of data interoperability within the information community
of environmental applications are reviewed. Spatial environmental
datasets held by the Malta Environment and Planning Authority
were used to assess the suitability of GML as a data standard.
Commercial data translators, and direct conversions using text
editors, were employed to convert geospatial data from proprietary
format to GML. The conversion process and the quality of the output
were evaluated. The practical research indicates that GML is not
yet a mature technology. Although the encoding could represent
most of the characteristics of the case study datasets; the interoperability
of the data was compromised. This was due to vendor specific treatment
of the GML coding.
GIS Education from the necessary perspectives
Abstract: As Geographic Information Systems and Science education
programs proliferate, the dichotomy between practical Geographic
Information Systems training versus theoretical Geographic Information
Science education grows. As a result, education programs now vary
considerably in accreditation, duration and content. In the last
fifteen years there have been four significant efforts to develop
core curricula for Geographic Information Systems and Science
education programs. These efforts, primarily driven by the National
Center for Geographic Information and Analysis and the University
Consortium for Geographical Information Science have also included
contributions from the international community. Additional efforts
by the Association of Geographic Information Laboratories in Europe
round out the key efforts involved in developing common, core
curricula. As the dichotomy grows, educators, students and employers
must now grapple with a common understanding of education program
content and the degree to which this content is practical or theoretical.
If tools and methods were developed that could assist these vested
parties, each with their own unique perspective on education content,
then better communication on existing and ideal content would
be facilitated. This thesis presents the results of research performed
on curriculum efforts, defines known global Geographic Information
Systems and Science education programs and provides a methodology
for classifying and quantifying common core content in programs.
In addition a methodology is proposed for measuring perspectives
on content in ideal Geographic Information Systems and Science
education programs as well as existing ones. The research culminates
with the development of the educational cartogram as a means of
displaying quantified perspectives of education programs in a
graphical sense. Better communication between all the perspectives
is the first step in resolving the practical versus theoretical
dichotomy.
The Effective Use of GIS in Natural Resource
Management at the Local Level
Abstract: The Earth's natural resources are under increasing threat,
especially from human activity. It has never been more important
to gather more information to be able to quantify those threats,
understand them and put in place initiatives and policies to counter
them. Every project of environmental conservation concern from
the Amazon Rainforest at one end of the scale to the local ancient
woodland at the other are all pieces of the same jigsaw. When
connected together the different pieces form a single 'Big Picture'
of an Earth that is diverse and complex in nature. When studying
this Earth, scientists often take a 'holistic' approach in the
belief that by observing its systems as a whole, a greater overall
understanding of its complexities, and the influences on it will
be gained. The local environmental system is a relatively small
component part of that much larger global system; nevertheless
the same principals and concepts apply at both ends of the scale.
Large-scale environmental study projects are driven by the need
to find remedies to problems that have potential global consequences.
This need demands that they are at the forefront of conceptual
thought, methods of study and technological advancement. Much
value can be gained from studying the large-scale systems and
applying the concepts that govern them to the development of the
local system. In an age of increasing environmental concern the
development of effective systems at all scales is paramount to
understand the world we live in and help to conserve the natural
resources we have left.
Realities of Interoperability: Case
study of Microsoft SQL Server and GeoMedia WebMap as an interoperable
GIS Solution
Abstract: With the wider adoption of GIS and the deployment of
web based applications, GIS is no longer confined to specialised
use within an organisation. Many organisations have moved to RDBMS
solutions for the management of spatial data to address issues
such as redundancy, duplication, backup and security. With e-government,
the e-citizen, better customer service and accountability, access
to data from public organisations is now expected. Methods to
achieve this access are becoming more necessary. The key to providing
this cross boundary enterprise access to data is interoperability.
The Open GIS Consortiums main aim is to provide specifications
to make GIS interoperability possible. This research looks at
the infrastructure in Irish local authorities for the dissemination
of GIS: Microsoft SQL Server and GeoMedia WebMap, and evaluates
its capacity to provide an interoperable GIS solution using Open
GIS specifications. This took the form of testing the OpenGIS
compliant add-ons provided with GeoMedia products and investigating
the setting up an interoperable spatial database in SQL Server.
Microsoft SQL Server does not provide spatial capabilities in
its core database but have developed MapPoint and MapPoint .NET
a web services product. The functionality and interoperability
of these products are reviewed. Due to the lack of GIS functionality
within SQL Server, the building of an OpenGIS compliant database
in SQL Server is beyond the scope of this research project. The
XML functionality provided with SQL Server is reviewed and possible
areas for development and further researchidentified. GML as a
data storage mechanism for spatial data is not practical for reasons
of performance and data size. Generating a Web Page was unsuccessful
due to the size of the GML files created. Replacing an RDBMS or
vendor proprietary format with GML is not yet a reality. Further
research using GML 3.0 and other possible uses of GML is recommended.
The research carried out using the Web Map Service adapter kit
was successful.. Using the Web Map Server is a practical, approach
to using the existing GIS infrastructure to provide interoperability
It could provide access to an organisations data across the web
without data conversion and without the need for data warehousing,
centralised databases, etc. Further research into the Web Map
Server and Web Feature Server Specifications are recommended.
The role of GIS in handling digital
spatial data in UK map libraries
Abstract: Spatial data provision is increasingly moving towards
digital format. This has great benefits for both the producer
in terms of cost savings as maps no longer need to be printed
and the user who can integrate their own data with spatial data
provided by national mapping agencies and other suppliers. The
impact of this on UK map libraries is significant and presents
challenges to be addressed. Map libraries in the United States
have developed strategies to handle digital spatial data and this
has been extensively described and analysed in the published literature.
However, comparatively little research has been carried out in
the UK to examine the impact here of digital spatial data. The
cessation of large-scale map printing by the Ordnance Survey for
example, has significant implications for legal deposit in the
UK and similar moves by other data providers are likely to follow.
The high cost of digital data means that map libraries are unlikely
to be able to extensively purchase data for their collections,
so the development of online data services such as Digimap, which
provides access to Ordnance Survey data, will play an important
role. Digital spatial data is often in raw format, which has implications
for access provision and the potential of GIS to handle digital
data in map libraries is an option that is being increasingly
adopted in the US and may provide an answer for UK libraries.
The traditional role of both map libraries and their librarians
is challenged, but research has shown that there is an awareness
of these changes and an enthusiasm to develop UK map libraries
as both data archives and spatial information providers.
Problems in mapping genealogical data for
the purposes of geographical analysis
Abstract: The aim of this dissertation was to investigate the
issues of mapping genealogical data of Victorian England and Wales,
with reference to assessing the suitability and spatial quality.
It is evident from the research carried out that GIS is becoming
more widespread and exploring new and exciting application areas.
This is driven by developments and improvements to computer technology,
which has enabled a greatly expanded number of potential spatial
data users. Historical geographers are now rediscovering new dimensions
in historical studies that were previously unavailable in their
search to explain and identify geographical patterns. Yet outside
the academic world genealogy has seemingly been overlooked. Why
is this? Genealogy is a growth area that is yet to be fully explored.
The application of GIS in the fields of modern day demographic
studies and socio-economics is proven and well documented. Clearly
the spatial analysis of family names and lineage is an ideal candidate
for GIS, but as with anything related to historical research and
analysis the availability of the data is crucial to producing
a meaningful, valid and successful conclusion. Given the expected
high data quality standards required today, is the quality of
historical data acceptable for GIS? The case study analysis has
highlighted many of the diverse problems that face integration
of genealogical data and GIS for the purposes of geographical
analysis.
The use of Web GIS to improve public participation
within local government
Abstract: The increase in the use of Web GIS by local authorities
has seen a wide variety of different systems and approaches. While
a large body of literature exists about the design and layout
of normal websites this has not been extended to those sites that
employ some form of GIS. The uses of those sites have not been
examined in terms of how they interact with the public and what
sort of information they provide. The way the Web GIS looks and
behaves all has an impact on how the public react to the information
presented. If designed with the customer in mind the site can
help to provide a value link between the citizen and local government,
encouraging them to put forward their views and ideas. The designer
needs to take into account the audience, the type of functions
it needs to perform and it's accessibility to the outside world.
Certain Web GIS systems have introduced channels which they can
feedback information on particular issues and how this data is
feed back can help to improve local democracy. Highlighting what
makes up a good public participation Web GIS (or PPGIS) means
that these concepts can be applied to a real example. The sustainability,
data quality and the community involvement all play a key role
in the sites success. The problems and pitfalls of creating such
a site help to highlight why there is only a limited number of
councils attempting to communicate to the public in this way.
Development of a Value-Based Approach
to GIS Mineral Potential Mapping: A Case Study of Gold Deposits
in Northern Nevada
Abstract: Weights of Evidence (WoE) modeling has been applied
in a number of GIS studies of mineral deposits and other natural
systems. WoE is a very useful tool in quantifying the spatial
relationships of a point data set, representing the points of
interest, to a series of polygonal datasets representing potential
location controls of the points. One drawback to the technique
is all of the data points are equal in their contribution to the
statistical results. In a standard WoE study, a point representing
a world-class ore body has the same influence on probability statistics
as an abandoned prospect. As a result, the results of these studies
are often biased to the more numerous but less productive prospects
instead of the less frequent but more desirable ore bodies. This
study examines the use of two techniques to incorporate the attribute
information, in this case the gold endowment of deposits, into
a WoE model. In first technique, the manual approach, the operator
selects the test polygons for each test case, determines the total
area of the polygons, and extracts the sum of the attribute values
for the points "captured" by the selected polygons using standard
map query techniques in a GIS program. These values are then entered
into a spreadsheet containing the WoE formulas and the WoE statistical
measures are calculated. For the second technique, the representative
points approach, the operator first creates a new points dataset
with each point representing a fixed amount of the attribute being
sought. The appropriate number of points are then placed within
the "footprint" of each study target. Since the attribute value
is now converted to a group of points, automated WoE calculation
modules such as those found in ArcSDM can be used to calculate
the WoE statistical values. However, the closely spaced points
within the target footprint of the larger deposits can cause problems
in the calculation of conditional independence and other statistical
measures of the validity of correlation between multiple map layers.
Despite how they are depicted on small scale maps, mineral deposits
and similar features are not dimensionless points but three-dimensional
objects. Errors may arise when a single point represents a surface
that may actually span several polygons within the evidentiary
layers The use of the representative points method, if the points
are correctly placed, can minimize these errors by allowing the
attribute values to be split among several polygons if they intersect
within the footprint of the mineralization. The study area for
this project is the northern part of the state of Nevada, USA.
Total gold endowment for the region exceeds 7,300 tonnes of metal
(235 million troy oz) with at least 20 deposits that are considered
world class. Evidentiary layers used in the study included geology,
geochemistry, mineral occurrences, and isotopic data. Over six
hundred individual WoE determinations were winnowed down to four
evidentiary evidence layers that showed the best WoE contrasts
combined with low conditional independence. These were combined
to create a deposit probability map that was then merged with
other layers to create a map depicting the likely gold content
of each unit cell. The highest values in this map compare favorably
with the actual locations of the largest deposits in the study
area.
Organisations involved in the management
of the environment need access to each other's data. However,
access to spatial environmental data are often constrained by
issues of cost, manpower, data quality, data classification, data
standards, copyright, organisational problems and data knowledge.
To overcome these constraints, many countries are in the process
of integrating a Spatial Data Infrastructure (SDI), improving
the management of environmental information by making the best
use of digital map data.This dissertation examines how the establishment
of an SDI would help to overcome these constraints in the country
of Zimbabwe, focussing in particular on habitat data.
The Southern African Development Community (SADC)
is providing support to Zimbabwe's spatial environmental data
community, in particular by establishing an SDI in the whole of
the SADC region in Southern Africa.
A national SDI effectively integrated in
Zimbabwe will be part of the wider regional SDI in the SADC region,
and these in turn will contribute to the proposed Global SDI. The
Global SDI will affect and support, through considering needs, the
regional and national SDI's.
Through programmes of work to support environmental
information systems in African countries and taking an overview
on these countries' needs, EIS-AFRICA is also helping to promote
moves towards SDI's.
GIS based habitat evaluation and modelling
for selected diurnal Lepidoptera coenoses
Abstract: There is an urgent need for butterfly habitat assessment
as an important component in conservation and development planning
for multiple species at multiple spatial scales. In order to take
into account the needs of different butterfly species, a basic
system of natural ecological classification of butterflies has
been devised based upon aggregations of the ecological properties
of butterfly species in Wachau, Lower Austria. Different model
levels were developed based upon the properties of each ecological
group of butterflies. Local or site-scaled models were developed
based upon a synthesis of literature review of the biology and
ecology of butterflies. Fine-scaled field surveys were used to
enable an accurate assessment of the suitability of potential
and actual habitats occupied by butterflies, based upon site-specific
habitat composition and structure combined with spatial and topographical
variables. Regional-scaled models were developed to evaluate habitat
suitability in the areas adjacent to a planned "Life Project Wachau",
and were based on the site-scale models, with field-survey-based
variables of habitat composition being replaced by viariables
obtained from remote sensing. An object based image analysis was
used to derive habitat composition on regional scale. Modelling
was done by means of fuzzy logic and GIS. The predictive power
of the developed models was high. The mean absolute error between
predicted and observed habitat suitability was 0,09 for site-scale
models, and 0,13 for regional scale models (values ranged between
0 and 1). The process of model development and application synthesizes
the sometimes diffuse literature, helps to identify knowledge
and data gaps to guide future research, and provides a framework
for improving habitat assessment with knowledge gained in the
future. These models can be an effective tool for conservation
planning, monitoring and management, and can contribute to a reduction
in development costs.
Local Government and the National Land and
Property Gazetteer
Abstract: The National Land and Property Gazetteer (NLPG) is considered
to be one of keystones of local e-government and a catalyst to
joining up information across government and beyond. Local government
has been put at the heart of the process by the commitment of
the Improvement and Development Agency (IDeA) to develop the NLPG
in a public-private partnership with Intelligent Addressing (IA).
At the end of January 2003, 200 local authorities had submitted
their Local Land and Property Gazetteer (LLPG) to the national
NLPG hub hosted by IA. This leaves 207 still to create an LLPG
and, based on IA's status figures, at various rates of progress.
Much has been written about the success of the NLPG but there
has also been some criticism and even suggestions that local government
is not the correct home for the NLPG. Investigation into the rates
of progress in local authorities may shed some light on the challenges
they face and determine whether there are insurmountable problems
that puts the whole NLPG process in doubt. Through a questionnaire
the most important people in this process - the local authority
officers - give their views on issues such as organisational support,
resources, data cleansing, sustainability and relationships with
the street gazetteer. The results are examined to identify examples
of successes in spite of difficult circumstances and failures
where all the correct conditions seem to be in place. All the
assembled information is examined to conclude whether local government
is the correct home for the NLPG and when, if ever, an up to date
NLPG feeding off 407 frequently maintained LLPGs will be achieved.
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