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  • 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.
1

Habitatový model potenciálního rozšíření argali \kur{(Ovis ammon ammon)} na jižním Altaji / Habitat model of potential distribution of argali \kur{(Ovis ammon ammon)} in South Altai

LHOTSKÁ, Pavla January 2010 (has links)
In this thesis I develop a model of potential distribution of argali (Ovis ammon ammon) in South Altai. There are two hypotheses of why the numbers of argali are declining, and I try to discover which of them is the most probable in our case. In the end I create a proposal for better conservation of the Ukok plateau, or (if you prefer) argali
2

Mapeamento de áreas suscetíveis a inundação por rompimento de barragem em ambiente semiárido / Mapping of areas susceptible to flooding by dam breaking in semi-arid environment

Oliveira, Alarcon Matos de 11 October 2016 (has links)
Barragens pode ser considerando como risco potencial, o conhecimento da forma provável que se comportaria uma onda de cheia (escoamento crítico), provocado pelo rompimento de barragem é muito importante para as populações que residem à jusante do barramento, como acontece em São José do Jacuípe. Isto por que em caso de rompimento torna-se necessário existir plano de evacuação para área afetada a jusante. Neste sentido destaca-se a utilização de modelos ambientais aliados ao SIG como eficaz ferramenta que possibilita mapear áreas com susceptibilidade a inundação em caso de rompimento. O HEC-RAS surge como poderoso modelo hidrológico capaz de efetuar o modelo para rompimento de barragem em integração com o Sistema de Informação Geográfica. E para classificar o grau de risco da população a jusante é fundamental a adoção de metodologia que contemple as variáveis inerentes à importância deste empreendimento, por tanto será utilizado à metodologia de Menescal (2001) por abarcar todas as facetas importantes de segurança de barragem. / Dams can be considering as a potential risk, knowledge of probable way to behave a flood wave (critical flow) caused by dam break is very important for people living on the bus downstream, as in São José do Jacuípe. This is because in case of breakage becomes necessary to have the evacuation plan for the downstream affected area. In this sense there is the use of environmental models combined with GIS as an effective tool that makes it possible to map areas with susceptibility to flooding in the event of disruption. The HEC-RAS comes as powerful hydrological model able to make the model for dam breaking in integration with Geographic Information System. And to classify the degree of risk of downstream population is essential to adopt methodology that considers the variables inherent importance of this project for both will be used to Menescal methodology (2001) to cover all the important facets of dam safety.
3

Mapeamento de áreas suscetíveis a inundação por rompimento de barragem em ambiente semiárido / Mapping of areas susceptible to flooding by dam breaking in semi-arid environment

Alarcon Matos de Oliveira 11 October 2016 (has links)
Barragens pode ser considerando como risco potencial, o conhecimento da forma provável que se comportaria uma onda de cheia (escoamento crítico), provocado pelo rompimento de barragem é muito importante para as populações que residem à jusante do barramento, como acontece em São José do Jacuípe. Isto por que em caso de rompimento torna-se necessário existir plano de evacuação para área afetada a jusante. Neste sentido destaca-se a utilização de modelos ambientais aliados ao SIG como eficaz ferramenta que possibilita mapear áreas com susceptibilidade a inundação em caso de rompimento. O HEC-RAS surge como poderoso modelo hidrológico capaz de efetuar o modelo para rompimento de barragem em integração com o Sistema de Informação Geográfica. E para classificar o grau de risco da população a jusante é fundamental a adoção de metodologia que contemple as variáveis inerentes à importância deste empreendimento, por tanto será utilizado à metodologia de Menescal (2001) por abarcar todas as facetas importantes de segurança de barragem. / Dams can be considering as a potential risk, knowledge of probable way to behave a flood wave (critical flow) caused by dam break is very important for people living on the bus downstream, as in São José do Jacuípe. This is because in case of breakage becomes necessary to have the evacuation plan for the downstream affected area. In this sense there is the use of environmental models combined with GIS as an effective tool that makes it possible to map areas with susceptibility to flooding in the event of disruption. The HEC-RAS comes as powerful hydrological model able to make the model for dam breaking in integration with Geographic Information System. And to classify the degree of risk of downstream population is essential to adopt methodology that considers the variables inherent importance of this project for both will be used to Menescal methodology (2001) to cover all the important facets of dam safety.
4

A GIS Model to Estimate a Sustainable Potential of Forest Fuel for Energy Generation in the Municipality of Växjö, Sweden / En GIS-modell för att uppskatta en bärkraftig potential av skogsbränslen för energiproduktionen i kommunen Växjö, Sverige

Wohletz, Gunnar January 2011 (has links)
Since the 1980s the municipality of Växjö in Southern Sweden has been increasingly focusing on using wood to produce energy for the region. A permanent and sustainable supply of wood material is therefore indispensable. The main source for this wood fuel is harvested wood from forests which can be used as energy, so-called forest fuel. The objective of this research is to develop a model to estimate a sustainable potential of forest fuel supply until the year 2050 for the municipality using a geographic information system (GIS). The model overall follows a top-down approach that consists of three sequential modeling steps which are generally applicable for biomass potential estimations: a theoretical, technical and the reduced technical potential. For input data the model uses georeferenced forest data (called kNN-Sweden) and topographic data about the study area to describe and narrow down the forest fuel potential by setting numerical or topographic (spatial) parameters for each modeling step. In this report forest data from 2005 has been used, which was obtained shortly before the storm ‘Gudrun’ hit and damaged great parts of the Swedish forest landscape. This factor might have resulted in slightly misleading estimated numerical modeling results concerning the actual future forest fuel supplies, but is not related to the overall layout of the model. The results show that the municipality of Växjö should be able to satisfy its demand for energy wood from harvested forest wood alone until around the year 2035, but might have shortages after that year until 2050 (and possibly beyond that). This thesis concludes that for the next 40 years the municipality of Växjö should not only rely on its annually available forest fuel capacity, but instead, different wood resources, such as recycled wood from constructions or furniture, have to be utilized or forest wood from years with surplus supply have to be stored for future tighter years. For more accurate results the modeling steps should be repeated with more recent forest data. The report also concludes that the estimation of the forest fuel potential in this study still lacks accuracy and that it is advised to treat the estimated numerical modeling results with caution. There’s still room for further improvement, and therefore possible error sources and suggestions for future work are listed. / North Sea Sustainable Energy Planning
5

A GIS Based Approach to Measure Walkability of a Neighborhood

MANTRI, ANUPAMA 23 April 2008 (has links)
No description available.
6

Object-Based Segmentation and Classification of One Meter Imagery for Use in Forest Management Plans

Wells, W. Kevin 01 May 2010 (has links)
This research developed an ArcGIS Python model that extracts polygons from aerial imagery and assigns each polygon a vegetation type based on a modified set of landcover classes from the Southwest Regional Gap Analysis Project. The model showed an ability to generate polygons that accurately represent vegetation community boundaries across a large landscape. The model is for use by the Utah Division of Forestry, Fire, and State Lands to assist in the preparation of forest management plans. The model was judged useful because it was easy to use, it met a designated 50% threshold of useable polygons, and it met a designated 50% threshold of vegetation class assignment accuracy.
7

Anticipating Urban Evacuations: A Planning Support System for Impact Reduction

Belhadj, Joshua S. 23 April 2008 (has links)
No description available.
8

Impact du changement climatique sur la distribution des populations de poissons. Approche par SIG, modèles et scénarios d'évolution du climat / Climate change impacts on fish species distribution. Approach using GIS, models and climate evolution scenario

Kaimuddin, Awaluddin Halirin 28 June 2016 (has links)
La compréhension des interactions liant la répartition des espèces, la biodiversité, les habitats marins et le changement climatique est nécessaire voire fondamentale pour la mise en oeuvre d’une gestion efficace de la conservation, par exemple la mise en place d’aires marines protégées. Dans cette étude, nous avons travaillé sur l’évolution de richesse de 89 espèces de poissons notées «rares» ou «exotiques» (observées en dehors de leur aire de répartition connue) lié au changement climatique. Nous avons modélisé et prédit leur distribution saisonnière par le modèle SIG en fonction de leurs niches écologiques (déterminée dans cette étude). En superposant tous les modèles en fonction du temps, cette approche permet d’identifier des zones d’occupation préférentielle de forte biodiversité (hotspots). La méthode offre une alternative pour mesurer la richesse d’espèces de façon saisonnière dans des zones peu connues, et de suivre leur mouvement au cours de temps, puis avoir information de base sur l’efficacité de positionnement des aires marines protégés liées à ces zones hotspots. La zone d’étude s’est située dans trois grands écosystèmes marins : le courant des Canaries, le plateau sud de l’Atlantique Européen et les mers celtiques. La région centrale est une zone de transition (entre les eaux tropicales et tempérés) connue pour sa sensibilité aux effets du changement climatique. De 1982 à 2012, la SST augmente constamment au fil du temps, avec des tendances et des magnitudes qui varient selon l’écosystème. Une augmentation du nombre d'espèces dans un écosystème dans une période a été généralement suivie par une tendance à la baisse ou à la hausse dans des écosystèmes adjacents. Les niches écologiques des espèces étudiées ont été estimées par l’extraction des valeurs environnementales à l’échelle mondiale au point d'occurrence au moment de l'observation. Les résultats de niches sont cohérents avec ceux obtenus à partir d’études observationnelles ou expérimentales. La flexibilité du modèle SIG nous a permis de suivre l'évolution saisonnière de distribution des espèces au fil du temps. En général, les espèces montrent une tendance à élargir leur distribution vers le nord, montrant l'effet du réchauffement de l'océan sur la distribution des poissons marins. L’approche de modèle peut être utilisée pour modéliser la distribution des espèces moins connues, ou dans des zones où les données d’occurrences sont peu nombreuses, ainsi que pour prédire le modèle de distribution future. L'analyse spatiale de la superficie des AMPs (Aires Marines Protégées) par pays appartenant à la zone d'étude, montre que le Royaume-Uni puis la France possèdent le plus grand nombre d'AMP ainsi que les superficies totales protégées les plus importantes. La fréquence à laquelle les AMPs (Aires Marines Protégées) sont touchées par les zones de hotspots est fortement influencée par les variations de l’environnement, les zones favorables évoluant alors au fil des saisons. Ainsi, il est important de prendre en compte les variations saisonnières pour la création des AMPs afin de préserver les capacités adaptative des espèces soumises au changement global. / Understanding connectivities among species distributions, biodiversity, marine habitats and climate change is necessary for the design of an effective conservation management, such as in the implementation of marine protected area (MPA). In this study, we observed the richness of 89 "rare" or "exotic" fish species (observed outside their known distribution range) related to climate change. We modeled and predicted their seasonal distributions according to the species ecological niches (determined in this study) using the GIS model. Superposing the models of all species using GIS, we determined the preferential zones or zones of high biodiversity (hotspots) over time. The GIS approach offers an alternative to measure seasonal species richness in poor-data areas. This approach allowed also species track movement over time. This information could be then used to measure the effectiveness of MPA positioning related to the hotspot areas. Our study area covers a wide latitudinal range of the Eastern Atlantic waters, from the warm tropical/subtropical waters to the temperate waters. This area is located in three large marine ecosystems: the Canary current, the South European Atlantic Shelf and the Celtic Seas. The transitional zone in the central region has well known for its sensitivity to the detection of climate change. From 1982 to 2012, the SST in all of studied ecosystems has increased consistently over time, with magnitude and trend varied among ecosystems. The change of number of species in each decadal period differed among ecosystems. Increasing number of species in an ecosystem was generally followed by decreasing trend in adjacent ecosystems. Species ecological niches were obtained by extracting the environmental values in the location of species occurrence at the time of observation. The environmental data and the occurrence records used were at global scale, and the methods yields coherent results with the results obtained from observational studies. The flexibility of GIS Model used in this study allowed us to follow the evolution of species seasonal distribution over time. Generally, most of the studied species showed a northbound trend in their distribution. These northbound tendencies were more evident in the middle region, confirming the effect of global warming in shifting marine species distribution. This approach provides an alternative of measuring seasonal richness of poor-known species and/or modeling in poor-data areas. The results present a complete picture of predictive number of species in an area over time. MPAs superficial analysis by country (countries lying in the study area) showed that UK has the highest number of MPA and the largest protected areas, following by France and Mauritania. Frequencies of the MPAs touched by the hotspot were strongly influenced by seasonal variations. Thus, considering seasonal variations in a conservation effort could preserve species adaptive variation under environmental changes. Overall, our works provide several alternative methods for species distribution studies and for studies poor-known species in data-poor area. The results provide evidences of ocean warming effect in shifting marine fish distribution.

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