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Improving road ice prediction through the introduction of GIS generated geographical parameters to an ice forecasting modelFry, Richard January 2010 (has links)
Network forecasting has traditionally been conducted using survey data collected by field-based surveys of the road network to model the microclimate surrounding the road network. A review of the literature in the subject area identifies that the current methods rely heavily on a field based survey approach. This research examines the premise that these field surveys replaced by modern GIS modelling methods. The research goes on to describe the development of a variety of GIS based methodologies and software for the calculation of geographical parameters for input into the Geographical Road Ice Prediction model and the dissemination of the resulting ice forecast through a web based GIS system. The methods developed are then discussed in relation to a trial conducted in Hampshire in the winter of 2006/7, which test the methods in a real world scenario. The final element to this research is the exploration of a variety of different GIS datasets to test the methodologies developed and investigate the impact of varying the methodologies and data sources on the network forecast for a small locality in the north of Hampshire. Results suggest that a number of the methodological parameters developed could be adjusted without affecting the resulting forecast and therefore improve the efficiency of the modelling process. It also identifies which of the GIS datasets available in the UK produce the best forecasting results. The research concludes that the methodologies developed have successfully helped predict ice formation on road networks without the use of any manual survey data. Moreover, the methods developed can be used in other research fields. In particular, this research has found a more accurate method for modelling building heights from medium resolution IFSAR data, which has resulted in an 11% improvement in building height estimations. Finally, this research goes onto discuss further research and how a more detailed assessment of the methodologies under different climatic and geographical conditions the methods developed, have the potential to replace parts or all of the survey methods currently used in ice prediction surveys.
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Crossing organisational boundaries : prerequisites for spatial data sharing in South AfricaWehn de Montalvo, Uta January 2001 (has links)
No description available.
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A Framework for a Multi-Participant Gis ProgramNabar, Maneesha Mangesh 17 April 1998 (has links)
The objective of this paper is to develop a well-defined and sound framework for the implementation of a multi-participant GIS program and to illustrate the developed framework by its application to the Departments of the Town of Blacksburg.
A multi-participant approach to implementing GIS technology faces greater challenges than a single-participant GIS project, due to the unique culture, structure, policy, decision-making rule and expectations of participants from implementation of GIS technology. So a successful program depends upon aligning different characteristics of the program's structure to those of participants, individually and collectively. Maximizing the system's potentials necessitates a well-defined implementation framework that can help manage changes and integrate the technology in organizations. Therefore, the paper focuses on the implementation aspects of multi-participant GIS programs.
The paper achieves its objective by exploring various issues involved in the implementation process of GIS technology and multi-participant GIS programs, develops a framework for implementing a multi-participant GIS program and applies the framework to the Departments of the Town of Blacksburg to achieve successful implementation. The illustration of the Town of Blacksburg identifies various constraints for multi-participant GIS program for which recommendations are provided to achieve successful implementation. / Master of Urban and Regional Planning
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Geography of Tuberculosis in the Greater Accra Region of GhanaDonkor, Kweku 05 1900 (has links)
In Ghana, spatial patterns of TB vary for different regions and variations may occur within the same region. This study examines TB distribution in the Greater Accra Region of Ghana using Geographic Information Systems (GIS). Behavioral, cultural and economic variables associated with TB morbidity are examined. From January 1998 to June 1999, data obtained from the Ghana Ministry of Health revealed that, men had a higher TB rate than women, TB was common among the age groups 20-29 and 30-39, and the average TB rate of 67.7 per 100, 000 population in the Greater Accra Region was higher than the national average (58.6 per 100,000 population). Using the human ecology model, this study attempts to explain the spatial distribution of the disease.
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Comparative Geospatial Analysis of Twitter Sentiment Data during the 2008 and 2012 U.S. Presidential ElectionsGordon, Josef 10 October 2013 (has links)
The goal of this thesis is to assess and characterize the representativeness of sampled data that is voluntarily submitted through social media. The case study vehicle used is Twitter data associated with the 2012 Presidential election, which were in turn compared to similarly collected 2008 Presidential election Twitter data in order to ascertain the representative statewide changes in the pro-Democrat bias of sentiment-derived Twitter data mentioning either of the Republican or Democrat Presidential candidates.
The results of the comparative analysis show that the MAE lessened by nearly half - from 13.1% in 2008 to 7.23% in 2012 - which would initially suggest a less biased sample. However, the increase in the strength of the positive correlation between tweets per county and population density actually suggests a much more geographically biased sample.
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Τεχνικογεωλογικός χάρτης Πελοποννήσου με τη χρήση GISΤσάφου, Κυριακή, Χατζηχαριστού, Ευαγγελία 20 April 2011 (has links)
Ψηφιοποίηση του τεχνικογεωλογικού χάρτη της Πελοποννήσου με τη χρήση του GIS. TO GIS μάς επιτρέπει την ανάκτηση διανυσματικών δεδομένων από στρωματογραφικούς χάρτες ή ψηφιακές δορυφορικές εικόνες και το συνδυασμό αυτό των δεδομένων για την επίλυση προβλημάτων. / -
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Urban Erosion Potential Risk Mapping with GISWeikmann, Amanda Maria 19 January 2018 (has links)
Federal, state and local governments are increasingly focused on the effects of development on water quality and quantity. With waterbodies being especially sensitive to certain pollutants, such as sediment and nutrients, regulations have been put in place to control the amount of pollutant that gets discharged. Sediment is a cause for concern as it originates during both rural and urban activities, and often carries other pollutants (metals, nutrients, etc.) with it. Existing erosion models focus primarily on estimating erosion from agricultural watersheds. Methods are needed to predict areas with high erosive potential (EP) in urban watersheds. Highlighting highly erosive areas in urbanized watersheds allows for the prioritization of maintenance and installation of Stormwater Control Measures (SCMs), and monitoring of sediment by municipal planners and engineers. This study utilizes commonly available geospatial layers in conjunction with a computational procedure to compute relative EP risk throughout a target urban watershed. A case study of the developed methodology was performed on a watershed in Blacksburg, VA, to generate EP risk maps. Results of the study indicate areas of erosive potential within the target watershed and provide a methodology for creating erosion potential risk maps for use by municipal planners and engineers / Master of Science / Federal, state and local governments are increasingly focused on the effects of development on water quality and quantity. With waterbodies being especially sensitive to certain pollutants, such as sediment and nutrients, regulations have been put in place to control the amount of pollutant that gets discharged. Sediment is a cause for concern as it originates during both rural and urban activities, and often carries other pollutants (metals, nutrients, etc.) with it. Existing erosion models focus primarily on estimating erosion from agricultural watersheds. Methods are needed to predict areas with high erosive potential (EP) in urban watersheds. Highlighting highly erosive areas in urbanized watersheds allows for the prioritization of maintenance and installation of Stormwater Control Measures (SCMs), and monitoring of sediment by municipal planners and engineers. This study utilizes commonly available geospatial layers in conjunction with a computational procedure to compute relative EP risk throughout a target urban watershed. A case study of the developed methodology was performed on a watershed in Blacksburg, VA, to generate EP risk maps. Results of the study indicate areas of erosive potential within the target watershed and provide a methodology for creating erosion potential risk maps for use by municipal planners and engineers.
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Predicting reptile species distributions and biogeographic patterns within Kruger National ParkBarends, Jody Michael January 2018 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / Knowledge of global reptile ecology is limited and there remains much to understand in terms of detailed reptile species information, including that of their distributions. In South Africa, despite being one of SANParks best-studied reserves, surprisingly little is known about the distributions and spatial ecology of reptiles within Kruger National Park (KNP). Management within KNP follows a strategic adaptive management strategy which monitors the statuses of animals using species or group specific indicators. Indicators are given predetermined upper and lower ranges of acceptable fluctuation before actions are taken. These ranges are referred to as thresholds of potential concern (TPCs), and for reptiles these are based on changes to their distributions across the landscape of KNP.
An apparent lack of high-quality reptile distribution data inhibits the effective monitoring of the statuses of these animals within KNP, which in turn limits management and conservation options. In this study, I use several methods to quantify available reptile occurrence data which formed the foundations for predicting the distributions of these species across KNP by means of species distribution modelling, with a view to gaining novel insight into reptile assemblage structure across the landscape of KNP.
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Modeling Historical Meander Bends Reconnection on the lower Long Tom River in Lane Co. and Benton Co., ORAppleby, Christina 21 November 2016 (has links)
Since the damming and channelization of the lower Long Tom River in the 1940s and 1950s, the quality and quantity of habitat for coastal cutthroat trout and spring Chinook salmon in the watershed has dramatically diminished. In order to better understand the potential for stream restoration, this study uses 2D hydraulic modeling to determine the impact of reconnecting historical meander bends to the main stem of the lower Long Tom River on localized flooding, sediment erosion and deposition, and salmonid physical habitat. These models compare the current conditions to two restoration scenarios that allow for fish passage given 1, 2, and 5-year flood events at two study sites. This study reveals important variations in the impact of restoration between the study sites and the reconnection methods. It also suggests that there is the potential for a large increase in the area of accessible habitat with stream restoration.
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Καινοτόμος τεχνική χωρικής διαίρεσης χαρτών πόλεων και αναπαράσταση χωρικών δεδομένων σε αυτούςΚαλαβρουζιώτης, Νικόλαος 02 April 2014 (has links)
Σκοπός της παρούσας εργασίας, αποτελεί η κατανόηση και η μελέτη των Γεωγραφικών Πληροφοριακών Συστημάτων (ΓΠΣ), και εν συνεχεία η ανάπτυξη μιας διαδικτυακής εφαρμογής, χρησιμοποιώντας συγκεκριμένα χαρακτηριστικά των ΓΠΣ.
Πιο συγκεκριμένα, έχοντας μια σαφή εικόνα των χαρακτηριστικών των ΓΠΣ, προχωρούμε στον σχεδιασμό και την υλοποίηση μιας εφαρμογής, που ως στόχο έχει την τμηματοποίηση και τον διαχωρισμό του χάρτη μιας δοθείσας περιοχής αστικού περιβάλλοντος, σε άλλες μικρότερες περιοχές. Ο διαχωρισμός αυτός δεν ακολουθεί μια αυθαίρετη λογική κατάτμησης, αλλά βασίζεται στον διαχωρισμό σε πολεοδομικά τετράγωνα, δημιουργώντας έτσι μικρότερες περιοχές ενδιαφέροντος.
Στο παρελθόν έχουν υλοποιηθεί αρκετές τεχνικές αναπαράστασης της χωρικής πληροφορίας πάνω στον χάρτη, όπως οι Heat Maps, οι Dot Density Maps, οι Proportional Symbol Maps, κ.ά. Ωστόσο, αν και σε πολλές περιπτώσεις είναι αρκετά αποδοτικές αυτές οι τεχνικές, συνήθως είναι δυσνόητες και ασαφείς ως προς την κατανόησή τους από μη-ειδικούς χρήστες. Στην εργασία αυτή, σε κάθε νέα περιοχή ενδιαφέροντος (πολεοδομικά τετράγωνα), προσδίδεται ένας χρωματισμός, ανάλογα με τα δεδομένα που εξάγουμε από τα μέσα κοινωνικής δικτύωσης, μια τεχνική όπου είναι εύληπτη και κατανοητή από τον άνθρωπο, και μπορεί μέσω αυτής να εξάγει εύκολα συμπεράσματα. / The purpose of this work is to understand and study Geographic Information Systems (GIS), and subsequently to develop a web application, using specific characteristics of GIS.
More specifically, having a clear picture of the characteristics of GIS, we proceed to the design and implementation of an application, which aims to segment and separate a given urban map area to other smaller one areas. This division does not follow an arbitrary logical partition, but is based on the separation in urban squares, thus creating smaller areas of interest.
In the past, several techniques have been implemented for representing of spatial information on the map, such as HeatMaps, Dot Density Maps, Proportional Symbol Maps, etc. However, although in many cases these are quite effective, these techniques are usually obscure and unclear in their understanding of non-skilled users. In this work, in each new region of interest (urban squares), imparted a coloring, depending on the data extracted from social networking, a technique which is accessible and understandable by users and easy conclusions can be exported through.
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