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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.
61

Caring for lhuq'us (pyropia spp.): mapping and remote sensing of Hul'qumi'num culturally important seaweeds in the Salish Sea

Baker, Jack 25 September 2020 (has links)
Hul’qumi’num communities on south eastern Vancouver Island have concerns about the status and safety of marine foods potentially impacted by environmental change and the urbanization and industrialization of their territories. Collaborative research undertaken with the Hul’q’umi’num’ Lands and Resources Society is part of a broader effort to revitalize cultural practices, language, and food systems. Lhuq’us (the Hul’q’umi’num’ language term for pohrpyra/pyropia spp. (commonly known as red laver or black gold)) is a flavourful and nutritious intertidal seaweed that grows on rocky beaches across the Pacific Northwest. Hul’q’umi’num’ language, cultural values, teachings, and family histories are all interwoven into the harvesting and consumption of lhuq’us in Hul’qumi’num territories. Lhuq’us is one of the species that have been persistently mentioned in conversations with state regulatory agencies and though these concerns have been raised for at least two decades there has been no systematic monitoring of the species. There are two broad streams of inquiry taken by thesis thesis. The first, employing ethnographic methodology including interviews and observant participation, seeks to both document the cultural values, oral histories, lived experiences associated with lhuq’us as well as concerns for the future collaborators have for lhuq’us and lhuq’us beaches. The second stream, based in a geographic approach, asks whether Unoccupied Aerial Vehicle (UAV) technologies could be employed to record the status of lhuq’us as a baseline for monitoring. Two study sites in the Salish sea were surveyed using UAV techniques: ȾEL,IȽĆ and St’utl’qulus. The overall accuracies of the UAV imagery classifications and the particular accuracies of the class representing lhuq’us suggest that UAV technologies paired with Google Earth Engine (GEE) object based image analysis (OBIA) methodologies can effectively detect lhuq’us. There are serious concerns and cultural values and practices deeply interconnected with culturally important species like lhuq’us. Through holding these concerns and values side by side with systematic observation and analyses maps and materials were created which communities can use to assert their rights, enact their own monitoring of territories and re-prioritize environmental decision-making done by federal, provincial, and municipal management agencies. / Graduate
62

Development of seagrass monitoring techniques using remote sensing data

Traganos, Dimosthenis 24 November 2020 (has links)
Our planet is traversing the age of human-induced climate change and biodiversity loss. Projected global warming of 1.5 ºC above pre-industrial levels and related greenhouse gas emission pathways will bring about detrimental and irreversible impacts on the interconnected natural and human ecosystem. A global warming of 2 ºC could further exacerbate the risks across the sectors of biodiversity, energy, food, and water. Time- and cost-effective solutions and strategies are required for strengthening humanity’s response to the present environmental and societal challenges. Coastal seascape ecosystems including seagrasses, corals, mangrove forests, tidal flats, and salt marshes have been more recently heralded as nature-based solutions for mitigating and adapting to the climate-related impacts. This is due to their ability to absorb and store large quantities of carbon from the atmosphere. Focusing on seagrass habitats, although occupying only 0.2% of the world’s oceans, they can sequestrate up to 10% of the total oceanic carbon pool, all the while providing important food security, biodiversity, and coastal protection. But seagrass ecosystems, as all of their blue carbon seascape neighbors, are losing 1.5% of their extent per year due to anthropogenic activities. This has adverse implications for global carbon stocks, coastal protection, and marine biodiversity. Seagrass and seascape recession necessitates their science and policy-based management, protection, conservation which will ensure that our planet will remain within its sustainable boundaries in the age of climate change. The present PhD Thesis and research aim is to develop algorithms for seagrass mapping and monitoring leveraging the recent emergences in remote sensing technology―new satellite image archives, machine learning frameworks, and cloud computing―with field data from multiple sources. The main PhD findings are the demonstration of the suitability of Sentinel-2, RapidEye, and PlanetScope satellite imagery for regional to large-scale seagrass mapping; the introduction and incorporation of machine learning frameworks in the context of seagrass remote sensing and data analytics; the development of a semi-analytical model to invert the bottom reflectance of seagrasses; the design and implementation of multi-temporal satellite image approaches in coastal aquatic remote sensing; and the introduction, design and application of a scalable cloud-based tool to scale up seagrass mapping across large spatial and temporal dimensions. The approaches of the present PhD cover the gaps of the existing scientific literature of seagrass mapping in terms of the lack of spatial and temporal scalability and adaptability; the infancy in seagrass and seascape-related artificial intelligence endeavours; the restrictions of local server and mono-temporal approaches; and the absence of new methodological developments and applications using new (mainly open) satellite image archives. I anticipate and envisage that the near-future steps after the completion of my PhD will address the scalability of the designed cloud-native, data-driven mapping tool to standardise, automate, commercialise and democratise mapping and monitoring of seagrass and seascape ecosystems globally. The synergy of the developed momentum around the global seascape with the technological potential of Earth Observation can contribute to humanity’s race to adapt to and mitigate the climate change impacts and avoid cross tipping points in climate patterns, and biodiversity and ecosystem functions.
63

An Enhanced Data Model and Tools for Analysis and Visualization of Levee Simulations

Griffiths, Thomas Richard 15 March 2010 (has links) (PDF)
The devastating levee failures associated with hurricanes Katrina and Rita, and the more recent Midwest flooding, placed a spotlight on the importance of levees and our dependence on them to protect life and property. In response to levee failures associated with the hurricanes, Congress passed the Water Resources Development Act of 2007 which established a National Committee on Levee Safety. The committee was charged with developing recommendations for a National Levee Safety Program. The Secretary of the Army was charged with the establishment and maintenance of a National Levee Database. The National Levee Database is a critical tool in assessing and improving the safety of the nation's levees. However, the NLD data model, established in 2007, lacked a structure to store seepage and slope stability analyses – vital information for assessing the safety of a levee. In response, the Levee Analyst was developed in 2008 by Dr. Norm Jones and Jeffrey Handy. The Levee Analysis Data Model was designed to provide a central location, compatible with the National Levee Database, for storing large amounts of levee seepage and slope stability analytical data. The original Levee Analyst geoprocessing tools were created to assist users in populating, managing, and analyzing Levee Analyst geodatabase data. In an effort to enhance the Levee Analyst and provide greater accessibility to levee data, this research expanded the Levee Analyst to include modifications to the data model and additional geoprocessing tools that archive GeoStudio SEEP/W and SLOPE/W simulations as well as export the entire Levee Analyst database to Google Earth. Case studies were performed to demonstrate the new geoprocessing tools' capabilities and the compatibility between the National Levee Database and the Levee Analyst database. A number of levee breaches were simulated to prototype the enhancement of the Levee Analyst to include additional feature classes, tables, and geoprocessing tools. This enhancement would allow Levee Analyst to manage, edit, and export two-dimensional levee breach scenarios.
64

Bangladesh Shoreline Changes During the Last Four Decades Using Satellite Remote Sensing Data

Guo, Qi January 2017 (has links)
No description available.
65

運用OpenGIS及免費軟體輔助國有公用不動產管理之研究 / Application of OpenGIS and free software for management of state-owned real estate

陳志清, Chen, Chih Ching Unknown Date (has links)
隨著時代科技之進步,國有財產管理由圖簿管理邁向資訊化管理已行之有年,惟現今之財產管理系統僅能掌握地籍屬性資料及管理機關的產籍資料,單張地籍圖無法與土地使用現況等空間資料結合,以圖形顯示土地及建物的位置及其空間分佈的分析,並且隨時掌握最新異動情形,導致國有土地未能獲得有效管理運用,被占用情形屢見不鮮。 自從1960年代加拿大地理資訊系統(CGIS)開始運作至今,雖然已有50年之歷史,但在早期,主要工作平台均為價錢昂貴之工作站電腦,其軟硬體價位極高,只有政府或大型研究機構才能負擔,所以GIS始終定位在專業用途,小老百姓一直無緣享受到GIS的好處。不過在近十年來的發展,使用者介面及軟硬體功能均已有長足進步,目前國際標準組織(ISO)與OGC (Open Geospatial Consortium)分別致力於地理資訊系統相關標準制定,迄今已分別推出許多與地理資訊描述與應用之相關標準。且我國對於國土資訊系統(NGIS)之開發整合及流通亦已投注相當心力,種種跡象均顯示GIS之開發門檻已逐漸降低中,且其資料之流通性亦提昇許多,因此本研究將嘗試探討如何利用開放式地理資訊架構(OpenGIS)、免費軟體(Free Software)及開放源碼軟體(Open Source Software),結合Google Earth涵蓋廣闊之地理資源平台,用最經濟且符合實際需求之方式,以地籍圖、地形圖及現況照片,結合既有國有土地及建物的管理屬性資料及相關地理圖形資料,如臺灣基本圖及地形圖等,以GIS的圖形及地理分析功能,輔助國有土地及建物管理之運用。 / With the advance of technology, the management of the state-owned property has been shifted from using map and book to information-based management for some time. However, the property management system today can only get hold of the management of cadastral property information and property registration of producing agencies, yet the cadastral map is not able to integrate with the current land utilization and other spatial data to illustrate the location and to analyze spatial distribution of the lands or buildings. And the fact that cadastral maps cannot be updated in time to grasp the latest alterations has resulted in ineffective management and utilization of state-owned land and arbitrary occupation was not uncommon. It has been fifty years since the operation of the Canadian Geographic Information System (CGIS) in 1960s. However, in the early stage, the working platform were mainly expensive workstation computers, and the prices of hardware and software were so expensive that only the government or large research institutions could afford. Therefore, GIS had been used only for special purposes; the pubic had no access to enjoy the benefits of GIS. However, from the development of the past decade, user interface as well as the function of hardware and software has made a great progress. At present, International Organization for Standardization (ISO) and Open Geospatial Consortium (OGC) are separately dedicated to developing geographical information standards and they have launched many standards regarding the description and application of geographical information respectively. Much effort on the integration and the circulation of our National Geographic Information System (NGIS) sees that the threshold of GIS development has been reducing and its circulation of data also has considerably raised. Therefore, this research attempts to combine OpenGIS, Free Software and Open Source Software with Google Earth, a platform that covers a wide geographical resource, with the most economical and realistic approach to integrate cadastral maps, topographic maps and present-day photos with the data of land and building management, and related geospatial data such as base map and topographic maps, etc. By using graphics and geographic analysis functions of GIS, it can support the management of state-owned land and buildings.
66

Χρήση WSN για ιχνηλάτηση της τροχιάς ενός κινητού με εφαρμογή του walking GPS

Αρβανιτόπουλος, Αναστάσιος 04 October 2011 (has links)
Τα τελευταια χρόνια ειμαστε μαρτυρες ενός εντυπωσιακού παραδόξου στο χώρο της τεχνολογίας. Ενώ όλη η ανθρωπότητα αναζητά το κάτι παραπάνω σε υπολογιστική ισχύ, σε χώρο αποθήκευσης και σε ταχύτητα, μικρές αυτόνομες συσκευές έρχονται να κατακτήσουν όλο και περισσότερους τομείς της καθημερινότητάς μας. Μονάδες με την ικανότητα της επεξεργασίας και της αποθήκευσης δεδομένων, της αίσθησης του περιβάλλοντος αλλά και της επικοινωνίας μεταξύ τους, ενσωματώνονται σχεδόν σε όλους τους τομείς δραστηριοποίησης του ανθρώπου. Ο τρόπος αυτό-οργάνωσης αυτών των κόμβων - μονάδων στα πλαίσια μεγάλων ασύρματων δικτύων αισθητήρων, και η συλλογή δεδομένων από μια ευρεία περιοχή, τους δίνει τη δυνατότητα λήψης αποφάσεων, πολλές φορές κρίσιμων, ανάλογα με τις επικρατούμενες συνθήκες. Τα παραπάνω χαρακτηριστικά των δομικών στοιχείων των ασυρμάτων δικτύων αισθητήρων, σε συνδυασμό με τις υπηρεσίες της υψηλής και καθιερωμένης τεχνολογίας του συστήματος GPS (Global Positioning System) μπορούν να δημιουργήσουν έναν εκρηκτικό συνδυασμό και ερευνητικές ιδέες για ανάπτυξη αστικών εφαρμογών αυτοματισμού, στο πλαίσιο των λεγόμενων «έξυπνων πόλεων». Μέσα σε ένα απέραντο δίκτυο ασυρμάτων αισθητήρων, αποτελούμενο από χιλιάδες οντότητες, η ικανότητα του κάθε κόμβου να εντοπίζει την θέση του και να την μοιράζεται με τους υπόλοιπους, κερδίζει ολοένα και περισσότερο έδαφος ειδικά σε θέματα δρομολόγησης. Η χρήση της τεχνολογίας GPS από έναν κόμβο, αντικείμενο που μελετάμε στη παρούσα εργασία, μπορεί να οδηγήσει από την επιτυχή εφαρμογή του Geographical Routing σε ένα WSN, μέχρι την υλοποίηση απαιτητικών εφαρμογών για αντιγραφή κίνησης αλλά και δημιουργίας «έξυπνων αυτοκινητόδρομων» μέσα στους οποίους θα γίνεται αυτόματη πλοήγηση των κινητών υπό την επίβλεψη ενός μεγάλου WSN με κόμβους που συνεργάζονται με το σύστημα δορυφορικού εντοπισμού θέσης αλλά και μεταξύ τους. Όπως γίνεται άμεσα αντιληπτό, η παρούσα εργασία, που πραγματεύεται την σωστή συνεργασία και επικοινωνία ενός δικτύου ασυρμάτων αισθητήρων με την τεχνολογία GPS για την ιχνηλάτηση της πορείας ενός κινητού, μπορεί να δώσει μελλοντική τροφή για ενασχόληση σε πολλαπλά ερευνητικά επίπεδα. Η εργασία μας χωρίστηκε σε τρείς θεματικές ενότητες. Η πρώτη αφορά τον τομέα του WSN και του προγραμματισμού των κόμβων, για επικοινωνία με τους δορυφόρους, με τον υπολογιστή αλλά και μεταξύ τους, με τις απαραίτητες λειτουργικές εφαρμογές που κληθήκαμε να υλοποιήσουμε. Η δεύτερη αναφέρεται στην εργασία μας από την πλευρά του υπολογιστή, που λειτουργεί σαν συλλέκτης των δεδομένων του δικτύου, και τη σύνδεση του συστήματός μας με την πρότυπη εφαρμογή Google EarthTM για απεικόνιση σε πραγματικό χρόνο της τροχιάς που ακολουθεί ένα κινητό. Η τρίτη ενότητα περιλαμβάνει εκτέλεση πειραμάτων χρήσης του συστήματος που σχεδιάσαμε και παράθεση οπτικοποιημένων αποτελεσμάτων, για την εύκολη εξαγωγή χρήσιμων συμπερασμάτων όσον αφορά στη λειτουργικότητά του. / The last few years we witness a striking paradox in the field of technology. While all humanity is seeking for more computing power, more storage capabilities and more proccessing speed, small autonomous devices have appeared to occupy more and more areas of our lives in the daily routine. Units with the capabilities of data proccessing, data storage, enviromental sensing and communication with each other, are incorporated in almost all areas of human activity. The way in which these nodes are self-organized into large Wireless Sensor Networks and their ability to collect data from a wide area, enables them in taking decisions, critical ones sometimes, according to the prevailing conditions. The above characteristics of the components of wireless sensor networks, combined with the services of the established and standard technology of the GPS (Global Positioning System) can create ideas for research and development of urban applications of automation in the so-called “smart cities”. In a vast network of wireless sensors, consisting of thousands of entities, the ability of each node to detect its position and share it with others, is gaining more and more ground especially in routing topics. The use of GPS technology from a node, which is one of the subjects we study in this thesis, could lead from the successful implementation of the Geographical Routing, to the implementation of more demanding applications for motion replication but also to creating “smart highways” through which mobiles will execute an automatic navigation, supervised by a large WSN consisting of nodes cooperating with the satellite positioning system and with each other. As is readily apparent, the present thesis which is dealing with the good cooperation and communication of a wireless sensor network with the GPS technology in order to trace the path of a mobile, can provide room for future involvement in multiple levels of research. Our work was divided into three thematic sections. The first concerns the field of WSN and node programming so that they can be able to communicate with satellites, with the computer and with each other, by installing them with the necessary functional applications that we had to implement. The second section refers to our work on the computer side, which acts as a network data collector, and the link of our system with the standard Google EarthTM application to display the path of a mobile in real – time. The third section includes conducting experiments using the system we designed. The results are visualised and listed for an easy extraction of usefull conclusions regarding the functionality of our system.
67

The Longest Journey

Bowie, Markus January 2017 (has links)
The Longest Journey is an experimental Master essay which consists of 27 images with accompanying texts. Part of the images are digital photographs and part of them are images created through a special process involving different software tools – mainly Adobe Photoshop and Google Earth. The texts comment on how the images themselves were created and how one might understand what they are and how they function as aesthetic objects and as potential catalysts for thought. / <p>The essay was published as part of a Master of Fine Art Degree exhibition with the same title. For an English translation of it and photographic documentation of the exhibition, please contact: markus.bowie@gmail.com</p>
68

Puerto Argentino, inhabited by the pirates and drunkards of the royalty / Puerto Argentino, inhabited by the pirates and drunkards of the royalty

Mlynarčík, Štefan January 2019 (has links)
Objectivity and neutrality of current makers of online maps is hampered by the fact that the most important of them who form the public opinion are largely commercial giants. Sensitivity of approaches is desirable especially in specific situations involving territorial disputes. The textual part of the thesis brings theoretical insights to the problematics of map makers policies and their preservation or violation. At the same time is describes critical cartography as a current opposition against governmental and cooperative mapping, of which counter-mapping processes are regularly used in art, too. Practical outcome attempts to reflect specific approaches of map makers depending on particular territorial disputes. It takes place mostly in online environment, using the functions of Google Street View or Google Earth and forms of counter-mapping on the OSM platform. The goal is to bring alternative realities complicating map makers policies and governing apparatus to map projects with the international coverage.
69

Study of surface and groundwater quality and quantity at watershed scale in Mississippi

Nepal, Dipesh 08 December 2023 (has links) (PDF)
Hydrology and water quality are affected by land use and climate changes. Mississippi’s diverse agro–ecosystem comprises of a range of land use land cover (LULC) including agriculture, forest, wetlands, urban, and grasslands. The objectives of this study were to investigate the impacts of various factors such as Best Management Practices (BMPs), wetlands, LULC, and climate changes on water quality and quantity. The hydrologic and water quality responses to dynamic LULC input in Soil and Water Assessment Tool (SWAT) were evaluated. Results showed that agricultural and forest expansion were major drivers of hydrologic and water quality changes in Big Sunflower River Watershed (BSRW), with agricultural expansion increasing runoff, sediments, and nutrients and forest expansion reducing these variables. The results showed that the integration of dynamic LULC and agricultural management operations in SWAT enables a more realistic representation of agricultural watersheds. Similarly, this study investigated the effects of wetland area changes overtime on surface and groundwater. Results demonstrated that 26% increase in wetland areas, reduced streamflow, sediments, total nitrogen, and total phosphorus by 2%, 37%, 13%, and 4% respectively as well as increased groundwater storage by 90 mm in selected sub–watershed. This highlighted the importance of preservation and restoration of wetlands to enhance the agro–ecosystem resilience to LULC change. Likewise, the effectiveness of BMPs in reducing sediment yield from critical areas within BSRW was assessed. Results demonstrated that BMPs reduced sediments by up to 50%, suggesting their usefulness in mitigating high sediment yield from agricultural areas. This study also assessed the impacts of climate change on streamflow and sediment loads and the role of waterbodies in mitigating those impacts. Results depicted a significant increase in future streamflow and sediment loads due to potential increase in precipitation and temperature. When waterbodies were simulated, projected change in annual streamflow was < 1%. However, the projected annual sediment loads reduced substantially by 44–46%, highlighting the role of waterbodies on watershed resilience to climate change. Overall, this dissertation study provides insights about the complex interactions between LULC, climate, anthropogenic activities, and water resources that can help to develop watershed management strategies to promote agricultural sustainability.
70

Wildfire Spread Prediction Using Attention Mechanisms In U-Net

Shah, Kamen Haresh, Shah, Kamen Haresh 01 December 2022 (has links) (PDF)
An investigation into using attention mechanisms for better feature extraction in wildfire spread prediction models. This research examines the U-net architecture to achieve image segmentation, a process that partitions images by classifying pixels into one of two classes. The deep learning models explored in this research integrate modern deep learning architectures, and techniques used to optimize them. The models are trained on 12 distinct observational variables derived from the Google Earth Engine catalog. Evaluation is conducted with accuracy, Dice coefficient score, ROC-AUC, and F1-score. This research concludes that when augmenting U-net with attention mechanisms, the attention component improves feature suppression and recognition, improving overall performance. Furthermore, employing ensemble modeling reduces bias and variation, leading to more consistent and accurate predictions. When inferencing on wildfire propagation at 30-minute intervals, the architecture presented in this research achieved a ROC-AUC score of 86.2% and an accuracy of 82.1%.

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