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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.
91

Mapping the unmappable in indigenous digital cartographies

Becker, Amy 01 May 2018 (has links)
This thesis draws on a community-engaged digital-mapping project with the Vancouver Island Coast Salish community of the Stz’uminus First Nation. In this paper, I discuss the ways in which conventional cartographic representations of Indigenous peoples are laden with methodological and visual assumptions that position Indigenous peoples’ perspectives, stories, and experiences within test-, proof-, and boundary-driven legal and Eurocentric contexts. In contrast, I frame this project’s methodology and digital mapping tools as an effort to map a depth of place, the emotional, spiritual, experiential, and kin-based cultural context that is routinely glossed over in conventional mapping practices. I argue elders’ place-based stories, when recorded on video and embedded in a digital map, produce a space for the “unmappable,” that which cannot, or will not, be expressed within the constructs of a static two-dimensional map. This thesis also describes a refusal to steep maps too deeply in cultural context for a public audience. I detail the conversations that emerged in response to a set of deeply spiritual, cultural, and personal stories to mark how the presence of Coast Salish law, customs, power structures, varying intra-community perspectives, and refusal came to bear on the production of “blank space” (interpreted colonially and legally as terra nullius) in this project’s cartographic representation. Finally, I conclude that Coast Salish sharing customs are embedded within networks of Coast Salish customary legal traditions, which fundamentally affects tensions that arise between storytelling and digital mapping technologies, between academic and community accountabilities, and between collective and individual consent. / Graduate / 2019-10-13
92

Ηχοβολιστική αποτύπωση του αναγλύφου του πυθμένα και διερεύνηση της οικολογικής κατάστασης της λιμνοθάλασσας Γιάλοβας, Ν. Μεσσηνίας, καθώς και ψηφιακή χαρτογράφηση των καλύψεων/ χρήσεων γης στην ευρύτερη προστατευόμενη περιοχή

Παπακωνσταντίνου, Μαρία 13 January 2015 (has links)
Στα πλαίσια της παρούσας έρευνας, μελετήθηκε η προστατευόμενη περιοχή του Οικολογικού Δικτύου Natura 2000: «Λιμνοθάλασσα Πύλου (Διβάρι), Νήσος Σφακτηρία, Αγ. Δημήτριος» με κωδικό GR2550004. Διεξάχθηκαν δύο εποχικές δειγματοληψίες, στις 31 Αυγούστου του 2012 και στις 21 Απριλίου του 2013. Η λιμνοθάλασσα της Γιάλοβας έχει έκταση περίπου 2,5 Km2, μέγιστο βάθος 1 m και επικοινωνεί με τον κόλπο του Ναυαρίνου μέσω ενός τεχνητού διαύλου. Αρχικά, πραγματοποιήθηκε η ηχοβολιστική αποτύπωση του πυθμένα, με χρήση ηχοβολιστή πλευρικής σάρωσης (Side Scan Sonar, SSS) με σκοπό να αποκαλυφθεί, τόσο η μορφολογία του βυθού, όσο και η παρουσία, η αφθονία και η χωρική κατανομή των υδρόβιων μακροφύτων. Κατόπιν, σε 9 προεπιλεγμένους δειγματοληπτικούς σταθμούς, πραγματοποιήθηκε καταγραφή των φυσικοχημικών παραμέτρων και συλλέχθηκαν δείγματα υδρόβιας χλωρίδας. Με τη βοήθεια του ηχοβολιστή πλευρικής σάρωσης μελετήθηκε, περίπου, το 37% της έκτασης της λιμνοθάλασσας. Μέσω αυτής της διαδικασίας, προέκυψαν 6 διαφορετικοί ακουστικοί τύποι που αντιστοιχούν σε 6 διαφορετικά ποσοστά φυτοκάλυψης: πυκνή (76-100%), λιγότερο πυκνή (51-75%), αραιή (26-50%), πολύ αραιή (6-25%), σπάνια (1-5%) και καθόλου (<1%). Αφού κατασκευάστηκε το μωσαϊκό του πυθμένα, με τη χρήση των λογισμικών Triton Isis και TritonMap (Delphmap) της Triton Imaging Inc., διαπιστώθηκε ότι, η λιμνοθάλασσα καλύπτεται από βλάστηση σε ποσοστό περίπου 25% ενώ, περίπου, το 75% δεν καταλαμβάνεται από κάποιο είδος υδρόβιας βλάστησης, και το υπόστρωμα είναι αμμώδες/ ιλυοαμμώδες (Μπούζος et al., 2002a). Τα αποτελέσματα του Αυγούστου έδειξαν ότι, η πυκνή φυτοκάλυψη φτάνει περίπου στο 2% της υπό μελέτη έκτασης, και χωρικά περιορίζεται κοντά στο δίαυλο επικοινωνίας με τη θάλασσα. Η υδρόβια χλωρίδα που απαντά στους σταθμούς αυτούς αποτελείται από τα είδη Ruppia cirrhosa σε μίξη με την Cymodocea nodosa, με κυρίαρχο είδος τη Ruppia cirrhosa. Όσο απομακρυνόμαστε από το δίαυλο, η πυκνή φυτοκάλυψη εναλλάσσεται με λιγότερο πυκνή, σε ποσοστό 1% επί του συνόλου, και αποτελείται από τα ίδια είδη. Η αραιή φυτοκάλυψη, απαντά σε ποσοστό 3% και χωρικά κατανέμεται στο δίαυλο επικοινωνίας, αλλά και στα νοτιοδυτικά της λιμνοθάλασσας, όπου, εκτός από τη Ruppia cirrhosa, απαντά και η Cladophora glomerata. To ποσοστό της πολύ αραιής φυτοκάλυψης κυμαίνεται γύρω στο 15% και χωρικά κατανέμεται, κυρίως, στα βορειοανατολικά της λιμνοθάλασσας, όπου απαντά μόνο η Ruppia cirrhosa, ενώ, σε ποσοστό 4%, η φυτοκάλυψη είναι σπάνια και απαντά στα βορειοδυτικά και στα κεντρικά σημεία της λιμνοθάλασσας. Τον Απρίλιο, η χωρική κατανομή των υδρόβιων μακροφύτων είναι ακόμα πιο περιορισμένη, με συμμετοχή μόνο της Ruppia cirrhosa, η οποία συγκεντρώνεται κυρίως, κοντά στο δίαυλο επικοινωνίας με τον κόλπο του Ναυαρίνου, καθώς εκεί ευνοείται η ανανέωση του νερού και οι περιβαλλοντικές συνθήκες είναι κατάλληλες για την ανάπτυξή τους. Τονίζεται επίσης ότι, τον Απρίλιο, συλλέχθηκε από τα βόρεια της λιμνοθάλασσας ένα είδος του γένους Ulva spp, που αποτελεί δείκτη ευτροφικών συνθηκών (Orfanidis et al., 2005, Aliaume et al., 2007). Γενικά, το κυρίαρχο είδος στη λιμνοθάλασσα, και τις δύο δειγματοληπτικές περιόδους, είναι το κοσμοπολίτικο είδος Ruppia cirrhosa το οποίο έχει καταγραφεί ξανά στην περιοχή (Tiniakos et al., 1997). Σε όλους τους δειγματοληπτικούς σταθμούς, καταγράφηκαν οι παράμετροι: θερμοκρασία, αλατότητα, pH και διαλυμένο οξυγόνο, αλλά και το βάθος της λιμνοθάλασσας, η διαφάνεια του νερού και η ένταση της φωτοσυνθετικά ενεργής ακτινοβολίας (PAR). Επιπλέον, υπολογίστηκαν οι συγκεντρώσεις της χλωροφύλλης-α, τα ολικά αιωρούμενα στερεά (TSS), οι συγκεντρώσεις των ανόργανων ενώσεων αζώτου και φωσφόρου, καθώς και τα επίπεδα της ολικής αλκαλικότητας των ανθρακικών και όξινων ανθρακικών ιόντων. Τα αποτελέσματα έδειξαν χωρική και χρονική διακύμανση όλων των παραμέτρων, με πιο σημαντικές τις διακυμάνσεις της θερμοκρασίας, της αλατότητας και της συγκέντρωσης των θρεπτικών ενώσεων αζώτου και φωσφόρου. H εποχική διακύμανση των περιβαλλοντικών παραμέτρων προκαλεί φυσικό stress στους υδρόβιους οργανισμούς επηρεάζοντας την αφθονία και εξάπλωσή τους (Crouzet et al., 1999). O έλεγχος των στατιστικώς σημαντικών διαφορών των φυσικοχημικών παραμέτρων, πραγματοποιήθηκε με τον έλεγχο Mann-Whitney U, ο οποίος έδειξε ότι υπάρχουν στατιστικώς σημαντικές διαφορές, μεταξύ των δύο εποχών, που αφορούν στις παραμέτρους: διαφάνεια, αλατότητα, θερμοκρασία, pH, TSS, NO2, CO3ˉ και HCO3=. Αντίθετα, δεν εντοπίστηκαν στατιστικώς σημαντικές διαφορές μεταξύ των δύο εποχικών δειγματοληψιών στις παραμέτρους: βάθος, διαλυμένο οξυγόνο, χλωροφύλλη-α, NO3, NH4 και PO4. Ενδεικτικά, η θερμοκρασία παρουσίασε μεγάλη εποχική διακύμανση, σημειώνοντας πολύ υψηλές τιμές τον Αύγουστο (28,80 C - 30,50 C), και πολύ χαμηλότερες τον Απρίλιο (19,0 0C - 20,40C). Η αλατότητα παρουσίασε μεγάλες διακυμάνσεις από σταθμό σε σταθμό, κυρίως τον Αύγουστο, αλλά και από εποχή σε εποχή. Συγκεκριμένα τον Αύγουστο, κυμάνθηκε από 42,73‰ έως 54,42‰ ενώ τον Απρίλιο κυμάνθηκε γύρω στο 31‰ σε όλη την έκταση της λιμνοθάλασσας. Επιπρόσθετα, το pH παρουσίασε στατιστικώς σημαντικές διαφορές, καθώς τον Αύγουστο κυμάνθηκε στο 8,23 κατά μέσο όρο, αναφορικά για όλη τη λιμνοθάλασσα, ενώ τον Απρίλιο παρουσίασε πτωτική τάση, αφού η μέση του τιμή ήταν 6,99. Όσον αφορά στις συγκεντρώσεις των θρεπτικών, τα αμμωνιακά ιόντα ήταν η κυρίαρχη μορφή αζώτου, καθώς παρουσίασε υψηλές τιμές και τις δύο δειγματοληπτικές περιόδους, ενώ, τα νιτρώδη ιόντα, παρόλο που διέφεραν στατιστικώς σημαντικά, σε γενικές γραμμές, κυμάνθηκαν σε χαμηλά επίπεδα και τους δύο μήνες (έως 0,010 mg/l). Το διαλυμένο οξυγόνο παρέμεινε σε φυσιολογικά επίπεδα και τους δύο μήνες, όπου η μέση τιμή του ήταν 8 mg/l. Το βάθος δεν μεταβλήθηκε σημαντικά, ενώ τα επίπεδα της χλωροφύλλης-α, ήταν υψηλά και τις δύο χρονικές περιόδους. Η ανάλυση Spearman έδειξε σαφείς συσχετίσεις μεταξύ των περιβαλλοντικών παραμέτρων. Ανάμεσα στις πιο σημαντικές συγκαταλέγονται, η αρνητική συσχέτιση της διαφάνειας με την εποχή και το βάθος. Επιπλέον, σημαντική είναι η αρνητική συσχέτιση της αλατότητας και της θερμοκρασίας με την εποχή, αλλά και η θετική συσχέτιση μεταξύ των δύο πρώτων. Στη συνέχεια, εξίσου σημαντική είναι η θετική συσχέτιση του pH με την αλατότητα και τη θερμοκρασία, αλλά αξιοσημείωτες είναι και οι θετικές συσχετίσεις που παρουσιάζουν τα TSS με τη θερμοκρασία και το pH, και η χλωροφύλλη-α με τη διαφάνεια. Σύμφωνα με τα κριτήρια που έθεσε η Οργάνωση για Συνεργασία και Ανάπτυξη (ΟΕCD) για τα στάσιμα ύδατα, προέκυψε η τροφική κατάσταση της λιμνοθάλασσας, με βάση τις μέσες και οριακές τιμές των παραμέτρων: TP, χλωροφύλλη-α και διαφάνεια (Secchi depth) (OECD, 1982). Έτσι, με βάση τη μέση συγκέντρωση του ολικού φωσφόρου χαρακτηρίζεται ως υπερτροφική τον Αύγουστο και ως ευτροφική τον Απρίλιο. Όσον αφορά στη χλωροφύλλη-α, με βάση τις μέσες και μέγιστες τιμές που σημειώθηκαν τον Αύγουστο, η λιμνοθάλασσα χαρακτηρίζεται ως ευτροφική, ενώ τον Απρίλιο χαρακτηρίζεται ως ευτροφική, με βάση τη μέση τιμή, αλλά ως μεσοτροφική, με βάση τη μέγιστη τιμή που καταγράφηκε. Τέλος, όσον αφορά στη διαφάνεια, σύμφωνα με τις μέσες και ελάχιστες τιμές της, η λιμνοθάλασσα, και τους δύο μήνες, χαρακτηρίζεται ως υπερτροφική. Με χρήση των Γεωγραφικών Συστημάτων Πληροφοριών (ΓΣΠ), και με υπόβαθρο ένα μωσαϊκό ορθοφωτοχαρτών της Κτηματολόγιο Α.Ε., που αποκτήθηκαν κατά το διάστημα 2007-2009, κατασκευάστηκε ο χάρτης των καλύψεων/ χρήσεων γης του συστήματος ταξινόμησης Corine Land Cover 2000, για ολόκληρη την προστατευόμενη περιοχή. Ακολούθως, έγινε η αντιστοίχηση των κατηγοριών καλύψεων/ χρήσεων γης που προέκυψαν, με τους τύπους οικοτόπων του Παραρτήματος Ι της Οδηγίας 92/43/ΕΚ, στο 3ο επίπεδο ταξινόμησης. Επιπλέον, πραγματοποιήθηκε μια ποιοτική σύγκριση μεταξύ του νέου χάρτη και του χάρτη του Corine Land Cover, που κατασκευάστηκε για την περιοχή το 2000. Με βάση το χάρτη που κατασκευάστηκε διαπιστώθηκε ότι, υπάρχει ποικιλία φυσικών τύπων οικοτόπων, που προσδίδουν στην περιοχή ιδιαίτερη οικολογική και αισθητική αξία. Περιμετρικά της λιμνοθάλασσας απαντούν μεσογειακά αλίπεδα (Juncetalia maritimi), καλαμώνες, μεσογειακοί λειμώνες υψηλών χόρτων και βούρλων (Molinio Holochoenion), παρόχθια δάση-στοές και λόχμες (Nerio-Tamaricetea και Securinegion tinctoriae), σχηματισμοί με αρκεύθους (Juniperus spp.), υποτυπώδεις κινούμενες θίνες, κινούμενες θίνες της ακτογραμμής με Ammophila arenaria και μονοετή βλάστηση μεταξύ των ορίων πλημμυρίδας και αμπώτιδας. Επιπλέον, στη νήσο Σφακτηρία, στους λόφους του Παλαιόκαστρου και του Πετροχωρίου, απαντούν απόκρημνες βραχώδεις ακτές με βλάστηση στη Μεσόγειο (με ενδημικά Limonium spp.), Garrigues της Ανατολικής Μεσογείου και φρύγανα ενώ, οι όχθες του ποταμού Σελά χαρακτηρίζονται από δάση ανατολικής πλατάνου (Platanus orientalis). Τονίζεται η σημειακή συμμετοχή του τύπου προτεραιότητας των θινών των παραλιών με αρκεύθους (Juniperus spp). Επιπλέον, σε μεγάλη έκταση, απαντούν οι αγροτικές καλλιέργειες, με κυρίαρχους τους ελαιώνες, περιοχές αστικού πρασίνου, δρόμοι αλλά και οικισμοί. Τα αποτελέσματα της παρούσας εργασίας όπως η αποτύπωση της μορφολογίας του πυθμένα της λιμνοθάλασσας και των καλύψεων/ χρήσεων γης, στα όρια της προστατευόμενης περιοχής και η περαιτέρω εκτίμηση της οικολογικής κατάστασης της λιμνοθάλασσας θα συμβάλλουν περαιτέρω στην ορθολογική διαχείριση της. / In the context of this research, the protected area of the «Natura 2000» ecological network: "Pylos Lagoon, Sfaktiria island, St. Dimitrios" with the sitecode GR2550004, has been studied. Two sampling campaigns were carried out, οn August 31st 2012 and on April 21st 2013. Gialova lagoon covers an area of 2.5 Km2 with a maximum depth of 1 m and is connected with the adjoining Navarino Bay, via a small channel. Firstly, side scan sonar bottom interpretation was carried out, in order to investigate, not only the morphology of the lagoon’s bottom, but also the presence, abundance and spatial distribution of aquatic macrophytes. In addition, physicochemical parameters were recorded in 9 different sampling stations. Furthermore, samplings of aquatic vegetation were carried out as well. Initially, with the use of SSS, roughly 37% of the lagoon’s surface has been studied. Side scan sonar imagery resulted in 6 different acoustic types, which correspond to 6 different percentages of plant cover: thick (76-100%), less than thick (51-75%), sparse (26-50%), too sparse (6-25%), rare (1-5%) and absent (<1%). Having built the mosaic of the bottom of the lagoon, with the use of software Triton Isis and Triton Map (Delphmap) of Triton Imaging Inc., it was found that, the lagoon is covered by vegetation at 25%, while 75% is not occupied by any kind of aquatic vegetation, but the substrate is sandy/mudsandy (Bouzos et al., 2002a). The results of August showed that the thick plant cover reaches approximately 2% of the study area, and it is spatially restricted near the communication channel with the sea. The aquatic flora which responds to these stations is Ruppia cirrhosa in mixing with the Cymodocea nodosa, with the Ruppia cirrhosa as the dominant species. When we move away from the communication channel, the thick plant cover alternates with less than thick, representing 1% of the total, and consists of the same species. The sparse plant cover responds to 3% and is spatially distributed in the communication channel, but also in the southwest of the lagoon, where, apart from the Ruppia cirrhosa, Cladophora glomerata is found as well. The percentage of too sparse vegetation is around 15%, and it is spatially distributed mainly in the north-east of the lagoon, where only Ruppia cirrhosa is found, while, the vegetation is rare at 4%, and responds to the northwest and the central points of the lagoon. In April, the spatial distribution of aquatic macrophytes is even more limited, involving only the Ruppia cirrhosa, which is mainly concentrated near the communication channel with the adjoining Navarino Bay, which favored the renewal of water and where the environmental conditions are suitable for their development. It should be also noted that, in April, an occasional species of the genus Ulva spp., was collected from the northern section of the lagoon. This species is an indicator of eutrophic conditions (Orfanidis et al., 2005, Aliaume et al., 2007). In general, the dominant species in the lagoon, in both sampling periods, is the cosmopolitan species Ruppia cirrhosa, which has been recorded before in the region (Tiniakos et al., 1997). The following parameters were recorded in all the sampling stations: temperature, salinity, pH and dissolved oxygen, but also the depth of the lagoon, the transparency of the water’s column and the volume of photosynthetically active radiation (PAR). Furthermore, chlorophyll-a, total suspended solids (TSS), inorganic nitrogen and phosphorus compounds, as well as the levels of total alkalinity of carbonates and acid carbonates were calculated. The results showed spatial and temporal variability of all parameters, and the most significant fluctuations were observed in temperature, salinity and in nitrogen and phosphorus concentrations. This seasonal variation of environmental parameters causes natural stress on aquatic organisms affecting their abundance and their spatial distribution (Crouzet et al., 1999). The control of the statistically significant differences in physicochemical parameters was carried out with the Mann-Whitney U test, which has shown that, there are statistically significant differences between the two seasons, relating to parameters: transparency, salinity, temperature, pH, TSS, NO2, CO3ˉ and HCO3=. In contrast, there were not statistically significant differences between the two sampling periods for parameters: depth, dissolved oxygen, Chl-a, NO3, NH4 and PO4. More specifically, the temperature has large seasonal variation, noting very high values in August (28.8ᵒ C – 30.5ᵒ C) and much lower in April (19.0ᵒ C – 20.4ᵒ C). The salinity showed large fluctuations from station to station, especially in August, but also from season to season. Specifically in August, it ranged from 42.73‰ to 54.42‰ and in April fluctuated around 31‰ throughout the lagoon. In addition, the pH values presented statistically significant differences. In August, pH ranged from around 8.23 on average, with respect to the entire lagoon, while in April showed a downward trend, when the average value was around 6.99. With regard to the concentrations of nutrients, ammonium ions were the dominant form of nitrogen, as it presented high values in both sampling periods, while the nitrite ions, although differed statistically significantly, in general, varied in low levels both months. Dissolved oxygen, remained at normal levels in both sampling periods, where the average value was around 8 mg/l. The depth did not change significantly, while the levels of Chl-a, were very high in both time periods. The Spearman analysis showed clear correlations between environmental parameters. Among the most important is, the negative correlation of transparency with season and depth. In addition, significant is the negative correlation of salinity and temperature with season, but also the positive correlation between the first two. Of course, equally important is the positive correlation of pH with salinity and temperature, but also significant are the positive correlations of the TSS with temperature and pH, and Chl-a with transparency. Finally, it is mentioned that there is negative correlation of total phosphorus with season and acid carbonates, and positive correlation with salinity, temperature, pH and TSS. In accordance with the standards set by the Organization for Cooperation and Development (OECD) for stagnant water, the trophic status of the lagoon has been established, on the basis of the average and maximum values of parameters: TP, Chl-a and transparency (Secchi depth) (OECD, 1982). So, on the basis of the average concentration of total phosphorus, it is characterized as hypereutrophic in August and as eutrophic in April. As regards the Chl-a, on the basis of the average and maximum values occurred in August, the lagoon is characterised as eutrophic, while in April it is characterized as eutrophic, based on the average value, but as mesotrophic, on the basis of the maximum value recorded. Finally, with regard to transparency, in accordance with the average and minimum values, the lagoon is characterized as hypereutrophic in both seasons. With the use of Geographical Information Systems (GIS) and with the help of ortho-corrected aerial photographs, acquired during 2007 and 2009, a Land Cover Land Use map was constructed. Subsequently, the categories of Corine Land Cover that came up, matched with the habitat types included in the Annex I of the Directive 92/43/EC, according to the 3rd classification level. Furthermore, the land cover/ land use categories of the new map compared with those of the map that constructed in 2000 for the same area, in order to estimate the changes during the years that have passed. The map, which was constructed in the context of this research, showed that there is a variety of natural habitat types, which gives the area special ecological and aesthetic value. In particular, around the lagoon, we found mediterranean salt meadows (Juncetalia maritimi), reedbeds, mediterranean grassland with high grass and rush (Molinio Holochoenion), southern riparian forest-arcades and scrubs galleries (Nerio-tamaricetea and Securinegion tinctoriae), formations with juniper thickets (Juniperus spp.), embryonic dunes, shifting dunes along the shoreline with Ammophila Arenaria and vegetation of drift lines. In addition, on the Sfaktiria island, in Paleokastro and Petrochori hills respond vegetated sea cliffs of the Mediterranean coasts (with endemic Limonium spp.), Garrigues of eastern Mediterranean and phrygana, while the banks of the river Selas are characterized by oriental plane woods (Platanus orientalis). The spot presence of dune juniper thickets is emphasized (Juniperus spp), which is a priority habitat. In addition, to a large extent, there are agricultural crops with olive groves, urban areas, roads and different kinds of settlements. The ultimate aim of this study is the visual interpretation of the morphology of the bottom of the lagoon and the Land Cover Land Uses, within the limits of the protected area and the further assessment of the ecological status of the lagoon.
93

Photorealistic visualisation of urban greening in a low-cost high- density housing settlement.

Donaldson-Selby, Gavin Hugh. January 2005 (has links)
Apartheid housing policies of the pre-1994 South African government, and the low-cost highdensity housing programmes of the post-1994 government, has given rise to numerous urban environmental problems, some of which could be addressed in a cost-effective and sustainable manner through urban greening, while simultaneously promoting biodiversity. Public participation in the planning of urban greening has been identified as being of vital importance, without which urban greening projects run a high, and expensive, risk of failure. Previous studies indicate that the greening priorities of residents in low-cost high-density housing settlements may differ considerably from those of managers and experts tasked with the protection and extension of the natural environment resource base. A system of participatory decision support is therefore required to reconcile the greening requirements of the community, and the ecological benefits of biodiversity. If language, literacy, map literacy and numeracy difficulties are to be avoided, and a sense of place or belonging is to be invoked, such a participatory decision support system should, ideally, be visually based, and capable of generating realistic eye-level depictions of the urban landscape. New computer-based landscape visualisation applications, which can directly utilise GIS, CAD and DEM data to produce detailed photo-realistic viewsheds, were deemed better suited to the task of visualising urban greening than existing GIS based mapping systems, CAD and traditional landscape visualisation methods. This dissertation examines the process of constructing a 3D computer model of the Mount Royal low-cost high-density housing settlement, situated in the eThekwini Municipality, KwaZulu-Natal, South Africa. Visualisations including terrain, natural features, indigenous vegetation, houses and roads were produced and submitted, with a questionnaire, to experts from different disciplines, Mount Royal residents and neighbors. Results from the expert survey indicate moderate support for visualisation in professional decision-making. However, both experts and residents expressed strong support for the accuracy and credibility ofthe visualisations, as well as for their potential in a participatory decision support system. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
94

A web-based GIS as a management tool for rock art sites in the Ukhahlamba-Drakensberg Park.

Grossmann, Carl Hector. January 2005 (has links)
The importance of managing and conserving cultural heritage can not be overemphasised. It is this realisation that has prompted the United Nations Educational, Scientific and Cultural Organisation (UNESCO) to declare identified sites of cultural importance as World Heritage Sites. The uKhahlamba-Drakensberg Park (UDP) was declared such a site in 2000, with its natural properties and cultural heritage as the criteria for inscription. The cultural heritage centres on the vast quantity of rock art that is renowned for its quality and diversity of subject. It is an important consideration for future generations to have the opportunity to view and understand this rich history and culture. There are increasing human and natural impacts on this non-renewable resource and to minimise these impacts and thus ensure the longevity of the resource it is necessary to develop a multi faceted selection of management and conservation tools. This realisation led the Programme of Geornatics, University of KwaZulu-Natal to conceptualise a project to develop a web-based Geographical Information System (GIS) specifically aimed at assisting in the management and conservation of rock art sites for the Valley of Pools in the Cathedral Peak Conservation Area of the UDP. Data for the project was captured in the field using Global Positioning System (GPS), digital camera and video camera as well as conventional hardcopy documentation. Existing digital spatial data and descriptive data were also collected from relevant stakeholders and a commercial organization. A pilot spatial database was then developed using ArcGIS@9 and Microsoft Access@, and later tested using a set of integrated simulated queries reflective of routine questions that users may request. Upon obtaining satisfactory responses to the queries, the integrated database was migrated and authored in ArcIMS®9 where it was further tested, and subsequently access was given to selected external professionals, both nationally and internationally, from various backgrounds, for evaluation purposes. Feedback from this process was favourably obtained. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
95

Sistema de navegação e localização para um robô escalador magnético de inspeção baseado em sensores LIDAR

Veiga, Ricardo Sales da 14 May 2015 (has links)
ANP; FINEP; MCT; CAPES / Este trabalho objetiva otimizar a localização de um robô móvel para a inspeção dos tanques de armazenamento de GLP -- Gás Liquefeito de Petróleo -- e permitir a navegação autônoma deste robô por toda a superfície do tanque. A falta de marcos no interior dos tanques levou ao desenvolvimento de uma solução envolvendo detecção de pequenas estruturas com sensores LIDAR (Light Detection and Ranging - Detecção e Telemetria por Luz) aplicada aos cordões de solda, estes sim presentes no interior do tanque, que é apresentada na primeira parte do trabalho. Em seguida, aplicando uma técnica de fusão de dados, as diferentes fontes de odometria presentes no robô são combinadas, permitindo uma precisão mais elevada na inspeção de modo geral. Por fim, o mapeamento e navegação simultâneos do exterior da esfera é abordado, a fim de se adicionar uma camada suplementar ao mapa digital, indicando os locais onde existem falhas. Testes para validação de cada uma das técnicas foram efetuados e uma análise de desempenho é apresentada ao final do trabalho. / This work aims to optimize localization of a climbing inspection robot for spherical LPG -- Liquified Petroleum Gas -- tanks and allow autonomous navigation along the entire surface of these tanks. One solution envolving small structures detection using LIDAR sensors is applied to the weld beads that are present inside the tanks. This solution is developed on the first part of this work. Following, a data fusion technique is used to combine the diferent odometry sources on the robot, resulting in a better, higher precision on the inspection as a whole. Finnaly, simultaneous mapping and navigation on the exterior of the spherical tank was studied in order to add one extra layer to the digital map, pinpointing the places where failures and weld beams were found. Validation tests for each one of this techniques are carried out and a performance analysis is also documented herein.
96

Sistema de navegação e localização para um robô escalador magnético de inspeção baseado em sensores LIDAR

Veiga, Ricardo Sales da 14 May 2015 (has links)
ANP; FINEP; MCT; CAPES / Este trabalho objetiva otimizar a localização de um robô móvel para a inspeção dos tanques de armazenamento de GLP -- Gás Liquefeito de Petróleo -- e permitir a navegação autônoma deste robô por toda a superfície do tanque. A falta de marcos no interior dos tanques levou ao desenvolvimento de uma solução envolvendo detecção de pequenas estruturas com sensores LIDAR (Light Detection and Ranging - Detecção e Telemetria por Luz) aplicada aos cordões de solda, estes sim presentes no interior do tanque, que é apresentada na primeira parte do trabalho. Em seguida, aplicando uma técnica de fusão de dados, as diferentes fontes de odometria presentes no robô são combinadas, permitindo uma precisão mais elevada na inspeção de modo geral. Por fim, o mapeamento e navegação simultâneos do exterior da esfera é abordado, a fim de se adicionar uma camada suplementar ao mapa digital, indicando os locais onde existem falhas. Testes para validação de cada uma das técnicas foram efetuados e uma análise de desempenho é apresentada ao final do trabalho. / This work aims to optimize localization of a climbing inspection robot for spherical LPG -- Liquified Petroleum Gas -- tanks and allow autonomous navigation along the entire surface of these tanks. One solution envolving small structures detection using LIDAR sensors is applied to the weld beads that are present inside the tanks. This solution is developed on the first part of this work. Following, a data fusion technique is used to combine the diferent odometry sources on the robot, resulting in a better, higher precision on the inspection as a whole. Finnaly, simultaneous mapping and navigation on the exterior of the spherical tank was studied in order to add one extra layer to the digital map, pinpointing the places where failures and weld beams were found. Validation tests for each one of this techniques are carried out and a performance analysis is also documented herein.
97

Predictive policing : a comparative study of three hotspot mapping techniques

Vavra, Zachary Thomas 21 April 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Law enforcement agencies across the U.S. use maps of crime to inform their practice and make efforts to reduce crime. Hotspot maps using historic crime data can show practitioners concentrated areas of criminal offenses and the types of offenses that have occurred; however, not all of these hotspot crime mapping techniques produce the same results. This study compares three hotspot crime mapping techniques and four crime types using the Predictive Accuracy Index (PAI) to measure the predictive accuracy of these mapping techniques in Marion County, Indiana. Results show that the grid hotspot mapping technique and crimes of robbery are most predictive. Understanding the most effective crime mapping technique will allow law enforcement to better predict and therefore prevent crimes.
98

Kartering van selfoontegnologie

Lochner, Hendrik Thomas 10 1900 (has links)
It is sincerely hoped that this work will motivate other researchers and in particular my colleagues to do further research in the field of cellphone technology, especially how it can be mapped to enable it to be utilised as evidence in our courts. This research aims to develop the mapping of cellphone technology as an aid in the investigation of crime. The mapping of cellphone technology refers to how cellphone technology can be utilised in crime investigation and in particular how a criminal can be placed at the scene of a crime, as a result of a cellphone call that was either made or received. To place the suspect at the scene of a crime as a result of a call made or received, cellphone records and technology of the relevant cellphone company, as well as present computer programmes can be utilised. Shortly, it can be said that a criminal can geographically be placed within a space some where on this earth. / Criminology / M.Tech. (Forensic Investigation)
99

Kartering van selfoontegnologie

Lochner, Hendrik Thomas 10 1900 (has links)
It is sincerely hoped that this work will motivate other researchers and in particular my colleagues to do further research in the field of cellphone technology, especially how it can be mapped to enable it to be utilised as evidence in our courts. This research aims to develop the mapping of cellphone technology as an aid in the investigation of crime. The mapping of cellphone technology refers to how cellphone technology can be utilised in crime investigation and in particular how a criminal can be placed at the scene of a crime, as a result of a cellphone call that was either made or received. To place the suspect at the scene of a crime as a result of a call made or received, cellphone records and technology of the relevant cellphone company, as well as present computer programmes can be utilised. Shortly, it can be said that a criminal can geographically be placed within a space some where on this earth. / Criminology and Security Science / M.Tech. (Forensic Investigation)
100

Utilisation des données d'élévation LiDAR à haute résolution pour la cartographie numérique du matériel parental des sols

Prince, Antoine 08 1900 (has links)
Les connaissances sur la morphologie de la Terre sont essentielles à la compréhension d’une variété de processus géomorphologiques et hydrologiques. Des avancées récentes dans le domaine de la télédétection ont significativement fait progresser notre habilité à se représenter la surface de la Terre. Parmi celles-ci, les données d’élévation LiDAR permettent la production de modèles numériques d’altitude (MNA) à haute résolution sur de grands territoires. Le LiDAR est une avancée technologique majeure permettant aux scientifiques de visualiser en détail la morphologie de la Terre et de représenter des reliefs peu prononcés, et ce, même sous la canopée des arbres. Une telle avancée technologique appelle au développement de nouvelles approches innovantes afin d’en réaliser le potentiel scientifique. Dans ce contexte, le présent travail vise à développer deux approches de cartographie numérique utilisant des données d’élévation LiDAR et servant à l’évaluation de la composition du sous-sol. La première approche à être développée utilise la localisation de crêtes de plage identifiées sur des MNA LiDAR afin de modéliser l’étendue maximale de la mer de Champlain, une large paléo-mer régionalement importante. Cette approche nous a permis de cartographier avec précision les 65 000 km2 autrefois inondés par la mer. Ce modèle sert à l’évaluation de la distribution des sédiments marins et littoraux dans les basses-terres du Saint-Laurent. La seconde approche utilise la relation entre des échantillons de matériel parental des sols (MPS) et des attributs topographiques dérivés de données LiDAR afin de cartographier à haute résolution et à une échelle régionale le MPS sur le Bouclier canadien. Pour ce faire, nous utilisons une approche novatrice combinant l’analyse d’image orientée-objet (AIOO) avec une classification par arbre décisionnel. Cette approche nous a permis de produire une carte du MPS à haute résolution sur plus de 185 km2 dans un environnement hétérogène de post-glaciation. Les connaissances issues de la production de ces deux modèles ont permis de conceptualiser la composition du sous-sol dans les régions limitrophes entre les basses-terres du Saint-Laurent et le Bouclier canadien. Ce modèle fournit aux chercheurs et aux gestionnaires de ressources des connaissances détaillées sur la géomorphologie de cette région et contribue à l’amélioration de notre capacité à saisir les services écosystémiques et à prédire les aléas environnementaux liés aux processus du sous-sol. / Knowledge of the earth’s morphology is essential to the understanding of many geomorphic and hydrologic processes. Recent advancements in the field of remote sensing have significantly improved our ability to assess the earth’s surface. From these, LiDAR elevation data permits the production of high-resolution digital elevation models (DEMs) over large areas. LiDAR is a major technological advance as it allows geoscientists to visualize the earth’s morphology in high detail, even allowing us to resolve low-relief landforms in forested areas where the surface is obstructed by vegetation cover. Such a technological advance calls for the development of new and novel approaches to realize the scientific potential of this new spatial data. In this context, the present work aims to develop two digital mapping approaches that use LiDAR elevation data for assessing the earth’s subsurface composition. The first approach to be developed uses the location of low-relief beach ridges observed on LiDAR-derived DEMs to map the extent of a large and regionally important paleo-sea, the Champlain Sea. This approach allowed us to accurately map the 65,000 km2 area once inundated by sea water. The model serves to the assessment of the distribution of marine and littoral sediments in the St. Lawrence Lowlands. The second approach uses the relationship between field-acquired samples of soil parent material (SPM) and LiDAR-derived topographic attributes to map SPM at high-resolution and at a regional scale on the Canadian Shield. To do so, we used a novel approach that combined object-based image analysis (OBIA) with a classification tree algorithm. This approach allowed us to produce a fine-resolution 185 km2 map of SPM in a heterogeneous post-glaciation Precambrian Shield setting. The knowledge obtained from producing these two models allowed us to conceptualize the subsurface composition at the limit between the St. Lawrence Lowlands and the Canadian Shield. This insight provides researchers and resource managers with a more detailed understanding of the geomorphology of this area and contributes to improve our capacity to grasp ecosystem services and predict environmental hazards related to subsurface processes.

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