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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.
541

數位化原住民農耕知識之策略─以尖石泰雅族部落為例 / The Strategy For Digitization of Indigenous Knowledge of Farming ─ A Case Study of the Atayal Communities in Jianshih Village

張孟瑄 Unknown Date (has links)
原住民農耕知識乃長期適應自然環境,並與自然達成平衡關係之農耕方式,因此藉由探討原住民農耕知識,得提供高山農業政策上的建議。惟偏向質性的原住民知識,需萃取、轉化為科學形式,方能利用。是以,本研究以地理資訊系統為基礎、利用土地適宜性分析與羅吉斯迴歸為方法,設計一套適用於數位化原住民農耕知識的策略。此策略為一個迭代的循環,包含蒐集、轉換、分析與檢視的程序。首先,以量化方式蒐集原住民農耕知識,次將知識轉換成空間資料的形式,再透過分析將知識轉化成有意義的資訊,並以視覺化方式展示分析成果,而分析成果可用以檢視知識蒐集的完整性、檢驗知識轉換後的正確性,進而以為基礎,針對興趣點再度蒐集知識,如此反覆操作上述程序。以土地適宜性分析為核心之策略,可用以探究原住民農耕區位選取知識;以羅吉斯迴歸為主軸之策略,則以個別農耕地為基礎,驗證農耕行為與邊坡穩定性之關聯。本研究以尖石泰雅族部落為研究區域。研究發現此數位化原住民農耕知識策略是可行的,得以有效地達到原住民農耕知識蒐集、分析及展示的目標。數位化後的原住民農耕知識具體而明確,可作為相關政策之參考。 / Indigenous knowledge of farming is empirical rules based on a long-term interaction between human and organism which benefit to each other. As a result, by discussing indigenous knowledge of farming, it could provide positive suggestions for the cultivation on slope land. However, indigenous knowledge tends to be qualitative rather than quantitative. Thus, we need to translate it into a scientific formats so as to take use of it. Consequently, the paper which is based on GIS, utilizes land use suitability analysis and logistic regression aims to establish a strategy for digitizing indigenous knowledge of farming. Actually, the strategy is an iterative circle with the procedure of extraction, translation, analysis and review. Firstly, investigate indigenous knowledge of farming in quantitative way. Secondly, translate it into layers. Then, turn the fragmentary data into meaningful information, and illustrate it on the map. Finally, review the result whether it is comprehensive and reliable. We used land use suitability analysis as the strategy to explore indigenous knowledge of farming site selection. Similarly, we use logistic regression as the strategy to demonstrate the correlation between the practice of farming and slope stability. The Atayal communities in Jianshih village was used for testing of the above strategy. In conclusion, the strategy for digitizing indigenous knowledge of farming is feasible for investigating, analyzing and visualizing the indigenous knowledge of farming. Therefore, the result is quite clear and specific as an important supplement to policy.
542

An integrated GIS-based and spatiotemporal analysis of traffic accidents: a case study in Sherbrooke

Harirforoush, Homayoun January 2017 (has links)
Abstract: Road traffic accidents claim more than 1,500 lives each year in Canada and affect society adversely, so transport authorities must reduce their impact. This is a major concern in Quebec, where the traffic-accident risks increase year by year proportionally to provincial population growth. In reality, the occurrence of traffic crashes is rarely random in space-time; they tend to cluster in specific areas such as intersections, ramps, and work zones. Moreover, weather stands out as an environmental risk factor that affects the crash rate. Therefore, traffic-safety engineers need to accurately identify the location and time of traffic accidents. The occurrence of such accidents actually is determined by some important factors, including traffic volume, weather conditions, and geometric design. This study aimed at identifying hotspot locations based on a historical crash data set and spatiotemporal patterns of traffic accidents with a view to improving road safety. This thesis proposes two new methods for identifying hotspot locations on a road network. The first method could be used to identify and rank hotspot locations in cases in which the value of traffic volume is available, while the second method is useful in cases in which the value of traffic volume is not. These methods were examined with three years of traffic-accident data (2011–2013) in Sherbrooke. The first method proposes a two-step integrated approach for identifying traffic-accident hotspots on a road network. The first step included a spatial-analysis method called network kernel-density estimation. The second step involved a network-screening method using the critical crash rate, which is described in the Highway Safety Manual. Once the traffic-accident density had been estimated using the network kernel-density estimation method, the selected potential hotspot locations were then tested with the critical-crash-rate method. The second method offers an integrated approach to analyzing spatial and temporal (spatiotemporal) patterns of traffic accidents and organizes them according to their level of significance. The spatiotemporal seasonal patterns of traffic accidents were analyzed using the kernel-density estimation; it was then applied as the attribute for a significance test using the local Moran’s I index value. The results of the first method demonstrated that over 90% of hotspot locations in Sherbrooke were located at intersections and in a downtown area with significant conflicts between road users. It also showed that signalized intersections were more dangerous than unsignalized ones; over half (58%) of the hotspot locations were located at four-leg signalized intersections. The results of the second method show that crash patterns varied according to season and during certain time periods. Total seasonal patterns revealed denser trends and patterns during the summer, fall, and winter, then a steady trend and pattern during the spring. Our findings also illustrated that crash patterns that applied accident severity were denser than the results that only involved the observed crash counts. The results clearly show that the proposed methods could assist transport authorities in quickly identifying the most hazardous sites in a road network, prioritizing hotspot locations in a decreasing order more efficiently, and assessing the relationship between traffic accidents and seasons. / Les accidents de la route sont responsables de plus de 1500 décès par année au Canada et ont des effets néfastes sur la société. Aux yeux des autorités en transport, il devient impératif d’en réduire les impacts. Il s’agit d’une préoccupation majeure au Québec depuis que les risques d’accidents augmentent chaque année au rythme de la population. En réalité, les accidents routiers se produisent rarement de façon aléatoire dans l’espace-temps. Ils surviennent généralement à des endroits spécifiques notamment aux intersections, dans les bretelles d’accès, sur les chantiers routiers, etc. De plus, les conditions climatiques associées aux saisons constituent l’un des facteurs environnementaux à risque affectant les taux d’accidents. Par conséquent, il devient impératif pour les ingénieurs en sécurité routière de localiser ces accidents de façon plus précise dans le temps (moment) et dans l’espace (endroit). Cependant, les accidents routiers sont influencés par d’importants facteurs comme le volume de circulation, les conditions climatiques, la géométrie de la route, etc. Le but de cette étude consiste donc à identifier les points chauds au moyen d’un historique des données d’accidents et de leurs répartitions spatiotemporelles en vue d’améliorer la sécurité routière. Cette thèse propose deux nouvelles méthodes permettant d’identifier les points chauds à l’intérieur d’un réseau routier. La première méthode peut être utilisée afin d’identifier et de prioriser les points chauds dans les cas où les données sur le volume de circulation sont disponibles alors que la deuxième méthode est utile dans les cas où ces informations sont absentes. Ces méthodes ont été conçues en utilisant des données d’accidents sur trois ans (2011-2013) survenus à Sherbrooke. La première méthode propose une approche intégrée en deux étapes afin d’identifier les points chauds au sein du réseau routier. La première étape s’appuie sur une méthode d’analyse spatiale connue sous le nom d’estimation par noyau. La deuxième étape repose sur une méthode de balayage du réseau routier en utilisant les taux critiques d’accidents, une démarche éprouvée et décrite dans le manuel de sécurité routière. Lorsque la densité des accidents routiers a été calculée au moyen de l’estimation par noyau, les points chauds potentiels sont ensuite testés à l’aide des taux critiques. La seconde méthode propose une approche intégrée destinée à analyser les distributions spatiales et temporelles des accidents et à les classer selon leur niveau de signification. La répartition des accidents selon les saisons a été analysée à l’aide de l’estimation par noyau, puis ces valeurs ont été assignées comme attributs dans le test de signification de Moran. Les résultats de la première méthode démontrent que plus de 90 % des points chauds à Sherbrooke sont concentrés aux intersections et au centre-ville où les conflits entre les usagers de la route sont élevés. Ils révèlent aussi que les intersections contrôlées sont plus à risque par comparaison aux intersections non contrôlées et que plus de la moitié des points chauds (58 %) sont situés aux intersections à quatre branches (en croix). Les résultats de la deuxième méthode montrent que les distributions d’accidents varient selon les saisons et à certains moments de l’année. Les répartitions saisonnières montrent des tendances à la densification durant l’été, l’automne et l’hiver alors que les distributions sont plus dispersées au cours du printemps. Nos observations indiquent aussi que les répartitions ayant considéré la sévérité des accidents sont plus denses que les résultats ayant recours au simple cumul des accidents. Les résultats démontrent clairement que les méthodes proposées peuvent: premièrement, aider les autorités en transport en identifiant rapidement les sites les plus à risque à l’intérieur du réseau routier; deuxièmement, prioriser les points chauds en ordre décroissant plus efficacement et de manière significative; troisièmement, estimer l’interrelation entre les accidents routiers et les saisons.
543

Application of a GIS Multi-Criteria Decision Analysis for the Identification of Intrinsic Suitable Sites in Costa Rica for the Application of Managed Aquifer Recharge (MAR) through Spreading Methods.

Bonilla Valverde, José Pablo, Blank , Clemens, Roidt, Mario, Schneider, Lisa, Catalin, Stefan 27 March 2017 (has links) (PDF)
Costa Rica’s annual mean precipitation is above 3300 mm, but this precipitation is not evenly distributed in time or space, producing clear differentiated wet and dry seasons in most of the country. Droughts are also common phenomena which greatly affect the availability of water resources. Managed aquifer recharge (MAR) schemes are being taken into consideration to enhance the underground water storage capacity of the country. The present study constitutes the first assessment for the identification of suitable sites for the implementation of MAR technology spreading methods (SM) in Costa Rica. The suitable sites are identified by means of a geographic information system multi-criteria decision analysis (GIS-MCDA) based on four criteria: hydrogeological aptitude, terrain slope, top soil texture and drainage network density. Four steps are performed in order to identify these sites: problem definition, screening for suitable areas, suitability mapping, and sensitivity analysis. The suitability map was divided in two zones after the screening: suitable and unsuitable, the first zone was further divided in five classes according to the weighted linear combination (WLC) ranking. The results indicate that 61% of the country is suitable for conducting SM. This map is a tool for future implementation of MAR techniques in the country.
544

L’irrigation dans le bassin du Rhône : gestion de l’information géographique sur les ressources en eau et leurs usages / Irrigation in the Rhône basin : geographic information system about freshwater resources and water uses

Richard-Schott, Florence 06 December 2010 (has links)
L’irrigation a connu de grands changements dans le bassin du Rhône français durant les trente dernières années du vingtième siècle. La mise en œuvre d’un Système d’Information sur le bassin du Rhône (SIR) montre l’existence de quatre grands systèmes d’irrigation qui s’individualisent au sein de plusieurs « régions d’irrigation ». Ces dernières révèlent des dynamiques contrastées, mettant à mal l’idée que l’irrigation aurait connu une expansion continue et homogène, même si les superficies irriguées augmentent globalement. Ces dynamiques spatiales s’expliquent par les profondes transformations d’une pratique modernisée, utilisant des techniques toujours plus économes en eau. C’est d’ailleurs le deuxième enseignement de la recherche : l’accroissement général des superficies irriguées n’a pas entraîné une augmentation des demandes en eau. Celles-ci ont plutôt tendance à diminuer, de l’ordre de 30 % en trente ans. Sous l’impulsion des gestionnaires, les irrigants font un usage de plus en plus raisonné des ressources en eau et, à terme, il ne faut certainement pas considérer l’irrigation comme une menace généralisée pour les équilibres environnementaux... Le mémoire de thèse s’accompagne d’un système de gestion de l’information géographique et d’un atlas en version électronique. / Over the last thirty years of the twentieth century, irrigation in the French basin of the Rhône river has undergone substantial change. The implementation of a Geographic Information System on the Rhône basin (SIR) demonstrates the existence of four main irrigation systems individualized within several “irrigation regions.” These reveal in turn a series of contrasted dynamics, putting into question the idea that irrigation expansion had been both continuous and homogeneous, even though the total surface area irrigated actually increased. These spatial dynamics can be accounted for by the deep transformations due to a modernised practice that relies on techniques ever more sparing with water. This is in fact the second lesson one can draw from this study : the general increase in irrigated surface areas did not lead to an increase in water demand. On the contrary, water demand has tended to diminish, in the order of 30% over thirty years. Driven by management, the cultivators’ use of water resources is more and more reasoned, so that in the long run irrigation is surely no global threat to environmental balance. The thesis includes a system for managing geographic information as well as an electronic atlas.
545

Spatiotemporal Analyses of Recycled Water Production

Archer, Jana E. 01 May 2017 (has links)
Increased demands on water supplies caused by population expansion, saltwater intrusion, and drought have led to water shortages which may be addressed by use of recycled water as recycled water products. Study I investigated recycled water production in Florida and California during 2009 to detect gaps in distribution and identify areas for expansion. Gaps were detected along the panhandle and Miami, Florida, as well as the northern and southwestern regions in California. Study II examined gaps in distribution, identified temporal change, and located areas for expansion for Florida in 2009 and 2015. Production increased in the northern and southern regions of Florida but decreased in Southwest Florida. Recycled water is an essential component water management a broader adoption of recycled water will increase water conservation in water-stressed coastal communities by allocating recycled water for purposes that once used potable freshwater.
546

The benefits and barriers to GIS for Māori

Pacey, H. A. January 2005 (has links)
A Geographic Information System visually communicates both spatial and temporal analyses and has been available for at least twenty years in New Zealand. Using a Kaupapa Māori Research framework, this research investigates the benefits and barriers for Māori if they were to adopt GIS to assist their development outcomes. Internationally, indigenous peoples who have adopted GIS have reported they have derived significant cultural development benefits, including the preservation and continuity of traditional knowledge and culture. As Māori development continues to expand in an increasing array of corporate, scientific, management and cultural arenas, the level of intensity required to keep abreast of developments has also expanded. GIS has been used by some roopū to assist their contemporary Māori development opportunities; has been suggested as a cost effective method for spatial research for Waitangi Tribunal claims; has supported and facilitated complex textual and oral evidence, and has also been used to assist negotiation and empowerment at both central and local government level. While many successful uses are attributed to GIS projects, there are also precautionary calls made from practitioners regarding the obstacles they have encountered. Overall, whilst traditional knowledge and contemporary technology has been beneficially fused together, in some instances hidden or unforeseen consequences have impeded or imperilled seamless uptake of this new technology. Challenges to the establishment of a GIS range from the theoretical (mapping cultural heritage) to the practical (access to data) to the pragmatic (costs and resources). The multiple issues inherent in mapping cultural heritage, indigenous cartography and, in particular, the current lack of intellectual property rights protection measures, are also potential barriers to successful, long-term integration of GIS into the tribal development matrix. The key impediments to GIS establishment identified by surveyed roopū were lack of information and human resources, and prioritisation over more critical factors affecting tangata whenua. Respondents also indicated they would utilise GIS if the infrastructure was in place and the cost of establishment decreased. Given the large amount of resources to be invested into GIS, and the opportunity to establish safe practices to ensure continuity of the GIS, it is prudent to make informed decisions prior to investment. As an applied piece of Kaupapa Māori research, a tangible outcome in the form of an establishment Guide is presented. Written in a deliberately novice-friendly manner, the Guide traverses fundamental issues surrounding the establishment of a GIS including investment costs and establishment processes.
547

Analysis of Mammoth Cave Pre-Park Communities

Brunt, Matthew 01 December 2009 (has links)
Before the creation of Mammoth Cave National Park, this area was home to numerous communities, each with a sense of identity. To prepare for the creation of the National Park, all residents living within these communities were relocated, and many of these communities were lost to the passage of time. Today, public memory of these lost communities is being fostered by the descendents of the pre-park area. Through the use of a Historical Geographic Information System, 1920 Edmonson County manuscript census data, and statistical analysis, the demographic composition of these lost communities was explored. This project not only brought to light a past that is not well known, but also built interest in sustaining public memory of the Mammoth Cave pre-park area through the use of historical GIS and public participation.
548

Analysis of storm surge impacts on transportation systems in the Georgia coastal area

Restrepo, Ana Catalina 18 November 2011 (has links)
Many Climate Scientists believe that global warming will produce more extreme weather events such as tropical storms, hurricanes, intense rainfall, and flooding. These events are considered to be the most catastrophic natural events for transportation systems especially in coastal areas. Due to the severe damage from storm surge and flooding. Evaluating the magnitude of possible storm surges and their impacts on transportation systems in coastal areas is fundamental to developing adaptation plans and impact assessments to mitigate the damage. This thesis focuses on existing transportation systems in the Georgia coastal area that could be affected by several storm surges. An existing storm surge model is used to estimate the storm surges and the surge heights based on the category, direction, and forward speed of a storm. The ground elevation of the ports, interstates, state roads, railroads, and the principal airports on the Georgia coast are identified through a GIS analysis using the national elevation data set. Having the storm surge elevation and the elevation of the existing infrastructure, a GIS study is performed to identify those parts of the transportation system that will be affected by each type of storm giving results such as the length or sections of transportation assets under or above the surge elevation. A literature review of storm surge, rising sea levels, and their impacts on coastal bridges, roads, airports, ports, and railroads is presented in the thesis. Also, a description of the software used to analyze and estimate the impacts of climate change on transportation systems is described.
549

Effects of local and landscape factors on grassland plant diversity / Effekte von lokalen und regionalen Faktoren auf den Artenreichtum im Grünland

Klimek, Sebastian 16 November 2006 (has links)
No description available.
550

Flächennutzungsmonitoring [I]

02 March 2015 (has links) (PDF)
Grundlage des Buches sind die Beiträge des 1. Dresdner Flächennutzungssymposiums. Dieses ist der Auftakt für eine zukünftig jährlich stattfindende Fachtagung, die Wissenschaft und Praxis zu Fragen der Erhebung, Entwicklung und Prognose der Flächennutzungsentwicklung zusammenführt. Das 1. Buch der beginnenden Reihe „Flächennutzungsmonitoring“ informiert über die amtliche Flächenstatistik einschließlich deren Datengrundlage und alternativer Datengrundlagen für die Flächenerhebung. In diesem Zusammenhang werden auch Indikatoren zur Beschreibung der Flächeninanspruchnahme und der Freiraumentwicklung vorgestellt. Da es hier auch immer wieder um Fragen der Visualisierung geht, werden Verfahren zur kleinräumigen Darstellung von Zustand und Entwicklung von Indikatoren auf verschiedenen räumlichen Ebenen bis hin zu Rasterkarten erläutert. Im abschließenden Beitrag geht es um die Konzeption eines Monitors der Siedlungs- und Freiraumentwicklung auf Grundlage von geotopographischen Basisdaten.

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