• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 821
  • 257
  • 56
  • 34
  • 23
  • 13
  • 11
  • 10
  • 10
  • 10
  • 10
  • 10
  • 10
  • 10
  • 8
  • Tagged with
  • 1507
  • 1507
  • 1507
  • 225
  • 214
  • 206
  • 194
  • 187
  • 175
  • 172
  • 165
  • 152
  • 148
  • 141
  • 141
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
841

Using Building Energy Simulation and Geospatial Modeling Techniques in Determine High Resolution Building Sector Energy Consumption Profiles

Heiple, Shem C. 01 January 2007 (has links)
A technique is presented for estimating hourly and seasonal energy consumption profiles in the building sector at spatial scales down to the individual taxlot or parcel. The method combines annual building energy simulations for cityspecific prototypical buildings and commonly available geospatial data in a Geographical Information System (GIS) framework. Hourly results can be extracted for any day and exported as a raster output at spatial scales as fine as an individual parcel (
842

Quantifying the benefits of hydrologic simulation and the implementation of active control for optimizing performance of green stormwater infrastructure

Bahaya, Bernard January 2019 (has links)
No description available.
843

Reconstructing the history of urban development in the mining town of Virginia, Free State between 1940 and 2015

Ajayi, Paul Oluwanifemi January 2017 (has links)
A research report submitted In partial fulfilment for the degree Master of Science (Geographical Information Systems & Remote Sensing). to the School of Geography, Archaeology & Environmental Studies, University of the Witwatersrand, Johannesburg , July 2017 / The nature of urban development experienced by mining towns across the world has been a subject of concern among urban planners because of its transitory nature. Most times mining towns develop gloriously into booming urban centres that create employment, generate wealth and satisfaction. All these fades into oblivion as soon as the mines get depleted. Mining towns often go through a number of urban processes which have been considered an expression of ‘infrastructural violence’ especially in the earlier stage of urban growth, and continually persists throughout the town’s life span. This research sought to reconstruct the history of urban development in the mining town of Virginia, Free State, and to quantify the manifestations of infrastructural violence throughout its timeline using GIS and remote sensing. Hence, land use and land cover maps were produced from aerial photographs, topographical maps and Landsat images through manual on-screen digitizing and classification using supervised support vector machine algorithms. Land use change detection analysis was conducted on the produced images using the cross classification and tabulation tool of QGIS 2.18.4 and the post classification tool of ENVI 5.3. Landscape metrics were employed to calculate the dimensions of growth and change experienced by all the land use classes during the timeline under study. Results obtained from this study confirmed the thoughts and findings of several theories vis a vis the nature of mining towns. Results reveal a rapid growth in the urban formal land use class up until 1995 with urban expansion and sprawl happening in the years between 1986 and 1995 with metrics of CA, NP and ED multiplying to twice their initial values ten years earlier. The urban informal land use class also experienced its subtle growth throughout the timeline of the study with its own urban expansion also happening between 1986 and 1995 with double increase in CA, NP and ED metric values. However, unlike the formal class that experienced decline after this period of urban expansion, the informal class continued to experience growth up until the end of the study period. Infrastructural violence was measured using the fractal dimension index (AWMPFD) of the landscape metrics for the formal and informal LU class. The results reveal continuous fragmentation throughout the period of study but with higher values in the years in which urban development started. / LG2018
844

Geographic Information System (GIS) Simulation of Emergency Power Production from Disaster Debris in a Combined Heat and Power (CHP) System

Ryals, Christopher Shannon 30 April 2011 (has links)
The objective of this study is to determine a predicted energy capacity of disaster debris for the production of emergency power using a combined heat and power (CHP) unit. A prediction simulation using geographic information systems (GIS) will use data from past storms to calculate an estimated amount of debris along with an estimated energy potential of said debris. Rather than the expense and burden of transporting woody debris such as downed trees and wood framing materials offsite, they can be processed (sorting and chipping) to provide an onsite energy source to provide power to emergency management facilities such as shelters in schools and hospitals. A CHP unit can simultaneously produce heat, cooling effects and electrical power using various biomass sources.This study surveys the quantity and composition of debris produced for a given classification of disaster and location. A comparison of power efficiency estimates for various disasters is conducted.
845

Using Geographical Information Systems to Investigate Spatial Patterns in Fossils of Tapirus polkenis from the Gray Fossil Site, Washington County, Tennessee

Ketchum, Winn Addison 01 December 2011 (has links) (PDF)
Discovered in 2000, the Gray Fossil Site provides a snapshot of the flora and fauna that lived during late Miocene to early Pliocene time in eastern Tennessee. These fossils occur in sediments consisting of fine-grained clays and sands of lacustrine origin, which were deposited after multiple sinkholes formed in the underlying Knox Group basement carbonates. Three-dimensional nearest neighbor analysis has been applied to fossils of Tapirus polkensis, characterizing the spatial patterns exhibited. These analyses determined the importance of taphonomic and depositional processes that occurred during the sites formation. Six characteristics were analyzed, four at the bone level including carnivore utilization, weathering, abrasion, and arthritis, and two at the specimen level, articulation and age class. Weathering, arthritis, and articulation, show clustered patterns indicating that the site had active predators, it consisted of many microenvironments, and deposition occurred in a passive setting. Although the current state of excavation makes any spatial analyses and taphonomic interpretations difficult, spatial analysis in both dimensions can be accomplished.
846

The Application of Pedology, Stable Carbon Isotope Analyses and Geographic Information Systems to Ancient Soil Resource Investigations at Piedras Negras, Guatemala

Johnson, Kristofer Dee 13 July 2004 (has links) (PDF)
The ancient inhabitants of the Maya Lowlands enjoyed a long and fruitful period of growth which climaxed at around AD 800. At that time, millions of people successfully subsisted in a challenging environment that today only supports a population a fraction of that size. These facts, and the subsequent "Maya Collapse", are the impetus of many recent studies that utilize environmental data, in addition to conventional archaeology, to investigate this Maya mystery. Pedological studies and stable carbon isotope analysis of soil organic matter, combined with Geographic Information Systems (GIS) are three tools that can be used to answer crucial questions as to how the Maya managed their soil resources. GIS maps that indicated areas of best agricultural potential based on slope and soil type were used as a guide to opportunistically sample soils in an area south of Piedras Negras Guatemala – an area that was densely vegetated and unexplored. Soils that represented the different soil resources of the area were sampled with a bucket auger at 15 cm intervals. The samples were then tested in a laboratory for physical and chemical characteristics and δ-13C values were determined for soil organic matter. Soil taxonomical descriptions indicated that overall the soil resources of the area were very good as almost all the soils were classified as Mollisols - the most fertile of all the soil orders. The suite of great groups found was Haprendolls, Argiudolls, Argiaquolls and Udorthents. The characteristics which distinguish these great groups were used to further investigate relative agricultural productivity from an ancient soil resources point of view. Haprendolls were better drained and probably made for good agricultural soils given soil depth and rainfall were adequate. The Argiudolls and especially the Argiaquolls were probably less favored because of very high clay contents that made them more difficult to work with and poor drainage. Stable carbon isotope analyses revealed strong evidence for maize agriculture in some environments of the study area. δ-13C values as high as -16.6‰ (76% C4—Carbon) were observed in areas of significant soil accumulation in well drained and moderately drained soils. Minimal evidence of maize agriculture was found in more marginal environments such as those with little soil accumulation or poorly drained areas. Also, the pattern of the graph of δ-13C values versus depth indicated that ancient agriculture occurred continuously in some areas, but in other areas as distinguishable events. Finally, when the strength of the C4 signal was represented graphically and overlaid with a modified GIS agricultural potential map, a visual representation of the extent and degree of ancient agriculture was achieved. Our findings suggest that upland agriculture was favored by the ancient Maya of Piedras Negras and that the region between Piedras Negras and Yaxchilan was an agriculturally important breadbasket. The methods and results of this study provide foundational information for the investigation of ancient Maya agriculture. In future studies, it may be possible to more systematically map ancient agricultural fields and estimate the carrying capacity of a region based on its soil resources.
847

Collaborative Web-Based Mapping of Real-Time Sensor Data

Gadea, Cristian January 2011 (has links)
The distribution of real-time GIS (Geographic Information System) data among users is now more important than ever as it becomes increasingly affordable and important for scientific and government agencies to monitor environmental phenomena in real-time. A growing number of sensor networks are being deployed all over the world, but there is a lack of solutions for their effective monitoring. Increasingly, GIS users need access to real-time sensor data from a variety of sources, and the data must be represented in a visually-pleasing way and be easily accessible. In addition, users need to be able to collaborate with each other to share and discuss specific sensor data. The real-time acquisition, analysis, and sharing of sensor data from a large variety of heterogeneous sensor sources is currently difficult due to the lack of a standard architecture to properly represent the dynamic properties of the data and make it readily accessible for collaboration between users. This thesis will present a JEE-based publisher/subscriber architecture that allows real-time sensor data to be displayed collaboratively on the web, requiring users to have nothing more than a web browser and Internet connectivity to gain access to that data. The proposed architecture is evaluated by showing how an AJAX-based and a Flash-based web application are able to represent the real-time sensor data within novel collaborative environments. By using the latest web-based technology and relevant open standards, this thesis shows how map data and GIS data can be made more accessible, more collaborative and generally more useful.
848

Improving usability of land warfare simulator: pathfinding and adaptive speed based on geographic data

Engström, Olof, Lördal Tigerström, Gabriel January 2017 (has links)
SANDIS II is a land warfare simulation and analysis tool developed by the Finnish Defence Research Agency. The Swedish Defence Research Agency has evaluated SANDIS II to have potential as a war gaming aid within education, at the Swedish Defence University. However, operating the tool is considered too difficult to avail that potential. In this report we propose a way of using geographical data for path-finding in terrain and automatically adjusting units’ speeds. We construct a cost raster from various types of geographic data, with each grid in the cost raster storing a value, representing a degree of mobility. Models using cost rasters are then created for adjusting unit speed and finding least-cost paths. We implement the models in Python as a stand-alone module, and describe the module’s internal methods, interface and how it can be used by SANDIS II. / SANDIS II är ett simuleringsoch analysverktyg utvecklat av Finska Försvarsmaktens Forskningsanstalt. Svenska Totalförsvarets forskningsinstitut har utvärderat SANDIS II och funnit ett potentiellt användningsområde för verktyget som stöd vid krigsspel, inom utbildning vid Försvarshögskolan. Verktyget anses dock vara för svårhanterligt för att uppfylla detta syfte. I denna rapport föreslås metoder för att beräkna de snabbaste förflyttningsvägarna i terräng och att automatiskt justera enheters hastighet i simulatorn, baserat på geografisk data. Vi konstruerar ett kostnadsraster av olika typer av terrängdata, där varje ruta i rastret tilldelas ett värde som representerar framkomlighet. Med kostnadsraster som grund skapar vi sedan modeller för att kunna justera enheters hastigheter och beräkna framryckningsrutter med så låg kostnad som möjligt. Vi implementerar modellerna i en separat Python-modul och beskriver modulens interna metoder, gränssnitt och hur det kan användas av SANDIS II.
849

Ekosystemtjänster : - med exempel från Flens kommun / Ecosystem services : - with examples from Flen

Ekström, Amanda January 2018 (has links)
Ekosystemen bidrar med många olika tjänster som är en förutsättning för att människans och samhällets behov ska kunna tillgodoses. Av den anledningen är det av största vikt att hänsyn tas till ekosystemtjänsterna och att de planernas för i stads- och samhällsplaneringen. Bland Sveriges miljömål finns ett par etappmål som handlar specifikt om ekosystemtjänster. Där framgår att vikten av ekosystemtjänsterna samt vad de påverkas av ska identifieras. Ekosystemtjänster kan delas in i fyra olika kategorier: Reglerande-, försörjande-, kulturella-, och stödjande ekosystemtjänster. De stödjande tjänsterna är en förutsättning för övriga tjänster och kan vara till exempel jordmånsbildning och geokemiska kretslopp. De kulturella tjänsterna är tjänster som bidrar till människans välbefinnande och hälsa, såsom friluftsliv och estetiska värden. De reglerande tjänsterna fås från naturens reglering vilket kan vara reglering av vattenflöden eller klimat. De försörjande tjänsterna är produkter som fås av naturen såsom livsmedel och vatten. Ekosystemtjänsterna påverkas av klimatförändringarna som innebär varmare och torrare klimat med risk för mer extrem nederbörd, exempelvis våtmarker riskerar att torka ut. Samtidigt är ekosystemtjänster viktiga då de motverkar effekter av klimatförändringarna. Bland annat minskar risken för översvämningar på grund av naturens förmåga att reglera vattenflöden och även hindra vatten från att nå markytan.   Syftet med rapporten är att identifiera ekosystemtjänster i Flen samt beskriva dess koppling till klimatförändringar. Resultatet kommer att fokusera på reglerande och kulturella ekosystemtjänster vilka har en stor betydelse i den bebyggda miljön. Resultatet fås och presenteras genom en litteraturstudie och inspiration från Metrias, Naturvårdsverkets, Huddinge kommuns och Högskolan i Gävles arbete med identifiering av ekosystemtjänster genom att studera ett områdes marktäcke. En karta tas fram över marktäcket i Flen och ekosystemtjänsterna presenteras sedan i en tabell, kopplande till marktäcke. Flens kommun består av mycket skog och sjöar. Där finns även åkermark och våtmark. Dessa marktäcken bidrar med många viktiga ekosystemtjänster från samtliga kategorier. / Ecosystems provide many different services that are essential for meeting human and social needs. For this reason, it is very important that ecosystem services are taken into account and are an important part of the urban planning. Among Sweden's environmental goals, there are two goals to achieve, that deal specifically with ecosystem services. The goals describe that the importance of ecosystem services and what they are affected by should be identified. Ecosystem services can be divided into four categories: regulating services, provisioning services, cultural services, and supporting ecosystem services. Supporting services are essential for the three other services. Two different supporting services is for example soil formation and geochemical cycles. The cultural services are services that contribute to well-being and health, such as outdoor activities and aesthetic values. The regulating services are obtained from nature’s natural regulations, which can be for example the regulation of water flows or the climate. The supply services are products obtained from nature such as food and water. Ecosystem services are affected by climate change, which means warmer and drier climate with the risk of more extreme precipitation, for example wetlands risk to become dry. At the same time, ecosystem services are important as they prevent the effects of climate change. For example, the risk of flooding is reduced due to the nature's ability to control water flows and also prevent water from reaching the ground surface.   The purpose of the report is to identify ecosystem services in Flen and describe its connection to climate change. The result will focus on regulating and cultural ecosystem services which are of great importance in the built environment. The result is obtained and presented through a literature study and inspiration from Metria, the Swedish Environmental Protection Agency, the town of Huddinge and the University of Gävle's work on identifying ecosystem services by studying an area's ground cover. A map is drawn over the covered area in Flen, and ecosystem services are then presented in a table linking to the ground cover. Flen consists of a lot of forests and lakes. There are also farmland and wetlands. These ground covers contribute many important ecosystem services from all four categories.
850

Tracking Violence: Using Neighborhood-level Characteristics In The Analysis Of Domestic Violence In Chicago And The State Of Illinois

Morgan, Rachel 01 January 2013 (has links)
Social disorganization theory proposes that neighborhood characteristics, such as residential instability, racial and ethnic heterogeneity, concentrated disadvantage, and immigrant concentration contribute to an increase in crime rates. Informal social controls act as a mediator between these neighborhood characteristics and crime and delinquency. Informal social controls are regulated by members of a community and in a disorganized community these controls are not present, therefore, crime and delinquency flourish (Sampson, 2012). Researchers have focused on these measures of social disorganization and the ability to explain a variety of crimes, specifically public crimes. Recently, researchers have focused their attention to characteristics of socially disorganized areas and the ability to predict private crimes, such as domestic violence. This study contributes to the research on social disorganization theory and domestic violence by examining domestic offenses at three different units of analysis: Chicago census tracts, Chicago neighborhoods, and Illinois counties. Demographic variables from the 2005-2009 American Community Survey were utilized to measure social disorganization within Chicago census tracts, Chicago neighborhoods, and Illinois counties. Data on domestic offenses in Chicago were from the City of Chicago Data Portal and data on domestic offenses in Illinois counties were retrieved from the Illinois Criminal Justice Information Authority (ICJIA). This study incorporated geographic information systems (GIS) mapping to examine the relationships between locations of domestic offenses and the measures of social disorganization in each unit of analysis. Results of this study indicate that different measures of social disorganization are significantly associated with domestic offenses in each unit of analysis.

Page generated in 0.1052 seconds