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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

Archeologia d'alta quota alle sorgenti del Brembo

Croce, Enrico 18 July 2022 (has links)
The focus of this research is the area known as Sorgenti del Brembo di Carona (sources of river Brembo of Carona), which is located in the Orobie Alps (province of Bergamo, Italy). The current archaeological activities in the area, carried out by the Civico Museo Archeologico di Bergamo, are site-specific and mainly focused on Iron Age rock engravings and on a medieval dwelling excavation. The present study aims at a wider approach to upland archaeology, more focused on landscape evolution rather than on single evidence. The starting point is the methodology developed in other alpine contexts, like the ALPES (Alpine Landscapes: Pastoralism and Environment of Val di Sole) project. The data, gathered through extensive field survey activities, assessed the presence of a complex landscape, with pastoral evidence, iron mining facilities and charcoal production sites, dating from Early Middle Ages to the present. All the collected data are managed through a GIS in order to maintain their spatial reference. Therefore, it was possible to easy cross-reference them with several historical documents (cartography, cadastres, archives) and also to perform quantitative and spatial analysis. This method allowed us to reconstruct a diachronic evolution of human activities impact on the landscape formation. An inductive predictive modelling based on the integration with ethnoarchaeology was also implemented using modern pastoral sites. The results shed light on the complex dynamics of the human approach to high-altitude regions and on the alpine environment constraints to human activities. On the other hand, it was also possible to asses both the strengths and biases of the current application of predictive models to Alpine cultural heritage. The methodology developed during this research, following and implementing previously developed methods, can be a step forward on the definition of a common archaeological approach to upland contexts. / Il progetto di ricerca nasce a seguito delle indagini archeologiche condotte dal Civico Museo Archeologico di Bergamo nel comune di Carona (BG), situato in alta val Brembana, sulle Alpi Orobie, che hanno permesso di identificare un sito cultuale con incisioni rupestri dell'età del Ferro e un villaggio minerario con fasi altomedievali e medievali. L'obiettivo principale della presente ricerca è stato ampliare la conoscenza storico-archeologica di tutto il territorio alla testata del Brembo di Carona, senza focalizzarsi su singoli siti e applicando le metodologie sviluppate all'Università di Trento nell'ambito del progetto ALPES (Alpine Landscapes: Pastoralism and Environment of Val di Sole), che prevedono un approccio al paesaggio montano in una prospettiva diacronica, inquadrabile nell'ambito della Landscape Archaeology. Le attività di ricerca sul campo hanno rappresentato il fulcro del progetto, permettendo l'individuazione di centinaia di evidenze antropiche. I dati raccolti sul campo sono stati contestualizzati attraverso l'analisi di diverse tipologie di fonti e materiali, non solo di tipo archeologico ma anche inquadrabili in ambiti storico-archivistici e topografici, con un’impostazione della ricerca in senso marcatamente interdisciplinare. L'elaborazione di un modello predittivo etnoarcheologico ha avuto il duplice obiettivo di fornire uno strumento di interpretazione delle strutture presenti sul territorio e di validare la stessa metodologia prognostica impiegata, già elaborata in ambito trentino. I dati raccolti e i risultati della loro analisi hanno permesso la ricostruzione diacronica di un paesaggio complesso, caratterizzato dalla compresenza di differenti attività economiche (pastorizia, attività minerarie e sfruttamento forestale), attraverso le quali si è espressa l'azione umana nell'ambiente montano lungo l'arco di più di un millennio. La metodologia proposta, in quanto sintesi di diverse esperienze di ricerca in ambito alpino, potrebbe porre le basi per una più ampia riflessione riguardo possibili approcci condivisi e comuni ad una "archeologia di montagna", che sempre più si sta delineando come una disciplina autonoma.
92

An integrated design process for durable concrete structures at the minimum environmental cost : application with the incorporation of rice husk ash / Μία ολοκληρωμένη διαδικασία σχεδιασμού για ανθεκτικές κατασκευές σκυροδέματος με το ελάχιστο περιβαλλοντικό κόστος : εφαρμογή με την ενσωμάτωση τέφρας φλοιού ρυζιού

Τάπαλη, Τζούλια 07 May 2015 (has links)
The construction industry is the largest consumer of materials in our society. Approximately 40% of all materials used are related to this section of the industry. Equivalent is the impact of the sector’s activities to the environment in terms of non-renewable energy sources (grey energy), gas emissions (mainly CO2), solid waste, etc. With concrete being the most widely used construction material (second only to water in total volumes consumed annually by society) and cement being the essential “glue” in concrete, emphasis should be placed on investigating and enforcing appropriate ways, methodologies and policies, to make cement manufacturing and the construction industry in general a more environmental friendly sector. At the same time, by considering, at one hand the significant amount of research and breakthroughs achieved on structural materials and design, as well as the level of sophistication of the modern European Standards and structural codes, and on the other hand, the increasing cases of premature deterioration of concrete structures, particular emphasis should also be placed on safeguarding the service life of reinforced concrete structures (in addition to tackling their environmental burden). That is why it is very important to introduce the sustainable way of thinking and the concept of industrial ecology on the preliminary design stages of a structure, on the material selection process and on the service life estimation stage, in achieving a robust durable reinforced concrete (RC) structure (for a given service life) with the minimum environmental burden. Thus, the main objective of the present Thesis is to focus on identifying and quantifying a structured framework of the appropriate methodologies in formulating an Integrated Design Process (IDP) for the design of durable and sustainable structures at the minimum environmental and economical cost (without compromising issues of structural safety) and also in identifying and demonstrating ways of industrial ecology for the sustainable development of the cement and construction industry. The present Thesis contributes to the evaluation of the environmental cost of each component of concrete and to provide the best possible mix design configuration (by means of a holistic analytical software tool) in terms of low environmental cost, as well as, to assess this proposed configuration in terms of strength and durability requirements. Overall, it has to be emphasized that through the present Thesis a new indicator is proposed for design purposes: the environmental cost, which can be added to the existing strength, durability and economic cost indicators towards an integrated design optimization of concrete structures. Finally, it is concluded that the incorporation of new Supplementary Cementing Materials (SCM), as biomass ashes and especially Rice Husk Ash (RHA), offers new perspectives for decreasing the environmental cost of constructions. / Η κατασκευαστική βιομηχανία αποτελεί τον μεγαλύτερο καταναλωτή υλικών στην κοινωνία μας. Περίπου το 40% όλων των υλικών που χρησιμοποιούνται σχετίζονται με αυτόν τον τομέα της βιομηχανίας. Αντίστοιχο αντίκτυπο έχουν και οι δραστηριότητες του τομέα στο περιβάλλον σε ότι αφορά τις μη ανανεώσιμες πηγές ενέργειας («γκρίζα» ενέργεια), αέριες εκπομπές (κυρίωςCO2 ), στερεά απόβλητα, κλπ. Δεδομένου ότι το σκυρόδεμα αποτελεί το πιο ευρέως χρησιμοποιούμενο δομικό υλικό (δεύτερο μετά το νερό σε συνολικούς όγκους που καταναλώνονται ετησίως από την κοινωνία) και ότι το τσιμέντο είναι η απαραίτητη «κόλλα» στο σκυρόδεμα, έμφαση πρέπει να δοθεί στη διερεύνηση και επιβολή κατάλληλων τρόπων, μεθοδολογιών και πολιτικών για τη μετατροπή της τσιμεντοβιομηχανίας και της κατασκευαστικής βιομηχανίας σε έναν γενικά περισσότερο περιβαλλοντικά φιλικό τομέα. Ταυτόχρονα, λαμβάνοντας υπόψη από τη μια μεριά τη σημαντική ποσότητα έρευνας και τα επιτεύγματα σχετικά με τα δομικά υλικά και τον σχεδιασμό, και επιπλέον το επίπεδο της επιτήδευσης των σύγχρονων Ευρωπαϊκών Προτύπων και κατασκευαστικών κανονισμών, και από την άλλη μεριά τις αυξανόμενες περιπτώσεις της πρώιμης φθοράς των κατασκευών από σκυρόδεμα, ιδιαίτερη έμφαση θα πρέπει να δοθεί στη διασφάλιση της διάρκειας ζωής των κατασκευών οπλισμένου σκυροδέματος (σε συνδυασμό με την αντιμετώπιση της περιβαλλοντικής τους επιβάρυνσης). Για το λόγο αυτό είναι ιδιαίτερα σημαντική η εισαγωγή του βιώσιμου τρόπου σκέψης και της έννοιας της βιομηχανικής οικολογίας στα προκαταρκτικά στάδια σχεδιασμού μιας κατασκευής, κατά τη διαδικασία επιλογής υλικών και κατά το στάδιο εκτίμησης της διάρκειας ζωής, ώστε να επιτευχθεί μια εύρωστη, ανθεκτική κατασκευή οπλισμένου σκυροδέματος (για δεδομένη διάρκεια ζωής) με την ελάχιστη περιβαλλοντική επιβάρυνση. Συνεπώς, ο κύριος στόχος της παρούσας Διατριβής είναι να επικεντρωθεί στον εντοπισμό και ποσοτικοποίηση ενός δομημένου προτύπου κατάλληλων μεθοδολογιών για τον σχηματισμό μιας Ενοποιημένης Διαδικασίας Σχεδιασμού για τον σχεδιασμό ανθεκτικών και βιώσιμων κατασκευών με το ελάχιστο περιβαλλοντικό και οικονομικό κόστος (χωρίς συμβιβασμούς σε θέματα που άπτονται της κατασκευαστικής ασφάλειας) και επίσης για την αναγνώριση και επίδειξη τρόπων βιομηχανικής οικολογίας για την βιώσιμη ανάπτυξη της βιομηχανίας τσιμέντου και σκυροδέματος. Η παρούσα Διατριβή συνεισφέρει στην αξιολόγηση του περιβαλλοντικού κόστους κάθε συστατικού του σκυροδέματος αλλά και στην παροχή ενός καλύτερου δυνατού σχεδιασμού σύνθεσης σκυροδέματος (μέσω ενός ολιστικού αναλυτικού λογισμικού) υπό όρους χαμηλού περιβαλλοντικού κόστους, καθώς και στο να αξιολογήσει την προτεινόμενη σύνθεση υπό όρους αντοχής και απαιτήσεων ανθεκτικότητας. Συνολικά, πρέπει να τονισθεί ότι στη παρούσα Διατριβή προτείνεται για πρώτη φορά ένας νέος δείκτης για σκοπούς σχεδιασμού: το περιβαλλοντικό κόστος, το οποίο μπορεί να προστεθεί στους υπάρχοντες δείκτες αντοχής, ανθεκτικότητας και οικονομικού κόστους προς μια ολοκληρωμένη αριστοποίηση σχεδιασμού κατασκευών από σκυρόδεμα. Τέλος, προκύπτει το συμπέρασμα ότι η ενσωμάτωση νέων συμπληρωματικών υδραυλικών υλικών (SCM: Supplementary Cementing Materials), όπως οι τέφρες βιομάζας και ειδικά η τέφρα φλοιού ρυζιού (RHA: Rice Husk Ash), προσφέρει νέες προοπτικές για τη μείωση του περιβαλλοντικού κόστους σκυροδέματος.
93

Comprendre les comportements des micelles de caséines dans des environnements variés, de leur équilibre minéral à leurs propriétés colloïdales et fonctionnelles : émulsion et coagulation présure / A comprehensive investigation of the behaviors of casein micelles in multiple environments, from their mineral balance to their colloidal and functional properties : focus on emulsion and rennet coagulation functionalities

Lazzaro, Fanny 27 October 2017 (has links)
Les micelles de caséines, composées de caséines, minéraux et eau, sont en équilibres dynamiques, elles échangent en permanence de leur matière avec leur environnement. Les micelles de caséines possèdent d’intéressantes fonctionnalités pour la fabrication de produits laitiers, telles que leur capacité à stabiliser des émulsions et à former des gels sous l’action de la présure. Des changements environnementaux, variations de pH, additions de sels ou d’agents chélatants, affectent les équilibres des micelles et induisent des modifications de leurs compositions et propriétés colloïdales. Ces changements modifient également leurs propriétés fonctionnelles, bien que cet aspect soit peu décri. Le but de ce projet était de comprendre les relations liant l’environnement, l’équilibre minéral, les propriétés colloïdales et fonctionnelles des micelles de caséines. L’impact de cinq facteurs (pH, Na3Cit, NaCl, CaCl2, MgCl2) modifiant les micelles fut étudié en focalisant sur leurs propriétés émulsifL’acidification et l’addition de Na3Cit ont causé les modifications minérales les plus importantes en solubilisant le phosphate de calcium micellaire. Le premier conduisit au « gonflement » des micelles alors que l’agent chélatant causa leur dissociation en petits agrégats. L’ajout de NaCl n’eut aucun impact sur le contenu minéral des micelles mais provoqua aussi la libération d’agrégats, révélée par cryo microscopie électronique et diffusion de rayons-X aux petits angles. Le rôle du phosphate de calcium sur les fonctionnalités fut confirmé et l’étude révéla l’importance de contrôler la libé / Caseins micelles, composed of caseins, minerals and water, are under dynamic equilibria, they constantly exchange materials with their surrounding environments. In addition, casein micelles possess valuable functionalities in regards to the formation of dairy products, such as the ability to stabilize emulsions or to form rennet gels. Environmental changes, such as variations in pH, additions of salts or chelating agents, affect the casein micelles equilibria and lead to modifications in their compositional and colloidal properties. Such changes also modify their functional properties, although this aspect is poorly described in the literature. This project aimed to understand the relationships that link the environmental modifications, the mineral balance, the colloidal and functional properties of the casein micelles. The impact of five modifying factors (pH, Na3Cit, NaCl, CaCl2, MgCl2) of the casein micelles were studied and the focus was placed on emulsion and rennet coagulation fuThe former only induce the swelling of casein micelles while the latter led to their disruption into smaller aggregates. NaCl had no impact on the micellar mineral content but also caused the release of small aggregates, as revealed by electronic microscopy and small angle X-ray scattering analyses. The decisive role of micellar calcium phosphate on the functionalities was confirmed and this study highlighted the importance of monitoring the release of small aggregates, as they strongly affected emulsions stability and gels firmness. CaCl2 and MgCl2 additions slightly increased the mineral c
94

Condições de vida e mortalidade por doenças cardiovasculares na área de influência do Complexo Petroquímico do Estado do Rio de Janeiro - COMPERJ. / Life conditions and mortality from cardiovascular diseases in influence area of Petrochemical Complex of Rio de Janeiro State - COMPERJ.

Helen Paredes de Souza 30 April 2014 (has links)
O objetivo desta tese foi identificar e caracterizar áreas com altas taxas de mortalidade por doenças do aparelho circulatório (DAC) e seus dois principais subgrupos de causas: as doenças isquêmicas do coração (DIC) e as doenças cerebrovasculares (DCV), entre os anos de 2008 e 2012 na área de influência do complexo petroquímico do estado do Rio de Janeiro COMPERJ, por meio de métodos estatísticos e sistemas de informações geográficas (SIG). Os resultados da investigação são apresentados na forma de dois manuscritos. O primeiro objetivou descrever o perfil da distribuição espacial da mortalidade por (DAC), caracterizar e predizer territórios com maior risco de morte por esta causa, com base em classificação das unidades espaciais por indicador de qualidade urbana (IQUmod). A análise multivariada foi realizada por meio do método conhecido como árvore de decisão e regressão, baseado em algoritmo CART para a obtenção do modelo preditivo para UVLs com diferentes riscos de mortalidade por DAC. O modelo desenvolvido foi capaz de discriminar sete conjuntos de UVLs, com diferentes taxas médias de mortalidades. O subconjunto que apresenta a maior taxa média (1037/100 mil hab.) apresenta 3 UVLs com mais de 75% de seus domicílios com abastecimento de água inadequado e valor de IQUmod acima de 0.6. Conclui-se que na área de influência do COMPERJ existem áreas onde a mortalidade por DAC se apresenta com maior magnitude e que a identificação dessas áreas pode auxiliar na elaboração, diagnóstico, prevenção e planejamento de ações de saúde direcionadas aos grupos mais susceptíveis. O segundo manuscrito teve por objetivo descrever o perfil da distribuição espacial da mortalidade por DIC e DCV em relação ao contexto socioambiental segundo áreas geográficas. O modelo de regressão linear de Poisson com parâmetro de estimação via quasi-verossimilhança foi usado para verificar associação entre as variáveis. Foram identificados como fatores de risco para mortalidade por DIC e DCV a variável relativa a melhor renda e maior distância entre domicílios e unidades de saúde; a proporção de domicílios em ruas pavimentadas aparece como fator de proteção. A distribuição espacial e as associações encontradas entre os desfechos e preditores sugerem que as populações residentes em localidades mais afastadas dos centros urbanos apresentam maiores taxas de mortalidade por DIC e DCV e que isto pode estar relacionado a contextos rurais de localização das residências e a distância geográfica destas populações aos serviços de saúde. Aponta-se para a necessidade de desenvolvimento de ações que propiciem maior amplitude no atendimento em saúde, no intuito da redução de eventos cardiovasculares mórbidos incidentes naquelas populações.
95

Condições de vida e mortalidade por doenças cardiovasculares na área de influência do Complexo Petroquímico do Estado do Rio de Janeiro - COMPERJ. / Life conditions and mortality from cardiovascular diseases in influence area of Petrochemical Complex of Rio de Janeiro State - COMPERJ.

Helen Paredes de Souza 30 April 2014 (has links)
O objetivo desta tese foi identificar e caracterizar áreas com altas taxas de mortalidade por doenças do aparelho circulatório (DAC) e seus dois principais subgrupos de causas: as doenças isquêmicas do coração (DIC) e as doenças cerebrovasculares (DCV), entre os anos de 2008 e 2012 na área de influência do complexo petroquímico do estado do Rio de Janeiro COMPERJ, por meio de métodos estatísticos e sistemas de informações geográficas (SIG). Os resultados da investigação são apresentados na forma de dois manuscritos. O primeiro objetivou descrever o perfil da distribuição espacial da mortalidade por (DAC), caracterizar e predizer territórios com maior risco de morte por esta causa, com base em classificação das unidades espaciais por indicador de qualidade urbana (IQUmod). A análise multivariada foi realizada por meio do método conhecido como árvore de decisão e regressão, baseado em algoritmo CART para a obtenção do modelo preditivo para UVLs com diferentes riscos de mortalidade por DAC. O modelo desenvolvido foi capaz de discriminar sete conjuntos de UVLs, com diferentes taxas médias de mortalidades. O subconjunto que apresenta a maior taxa média (1037/100 mil hab.) apresenta 3 UVLs com mais de 75% de seus domicílios com abastecimento de água inadequado e valor de IQUmod acima de 0.6. Conclui-se que na área de influência do COMPERJ existem áreas onde a mortalidade por DAC se apresenta com maior magnitude e que a identificação dessas áreas pode auxiliar na elaboração, diagnóstico, prevenção e planejamento de ações de saúde direcionadas aos grupos mais susceptíveis. O segundo manuscrito teve por objetivo descrever o perfil da distribuição espacial da mortalidade por DIC e DCV em relação ao contexto socioambiental segundo áreas geográficas. O modelo de regressão linear de Poisson com parâmetro de estimação via quasi-verossimilhança foi usado para verificar associação entre as variáveis. Foram identificados como fatores de risco para mortalidade por DIC e DCV a variável relativa a melhor renda e maior distância entre domicílios e unidades de saúde; a proporção de domicílios em ruas pavimentadas aparece como fator de proteção. A distribuição espacial e as associações encontradas entre os desfechos e preditores sugerem que as populações residentes em localidades mais afastadas dos centros urbanos apresentam maiores taxas de mortalidade por DIC e DCV e que isto pode estar relacionado a contextos rurais de localização das residências e a distância geográfica destas populações aos serviços de saúde. Aponta-se para a necessidade de desenvolvimento de ações que propiciem maior amplitude no atendimento em saúde, no intuito da redução de eventos cardiovasculares mórbidos incidentes naquelas populações.
96

ANATOMY OF FLOOD RISK AND FLOOD INSURANCE IN THE U.S.

Arkaprabha Bhattacharyya (9182267) 13 November 2023 (has links)
<p dir="ltr">The National Flood Insurance Program (NFIP), which is run by the U.S. Federal Emergency Management Agency (FEMA), is presently under huge debt to the U.S. treasury. The debt is primarily caused by low flood insurance take-up rate, low willingness to pay for flood insurance, and large payouts after major disasters. Addressing this insolvency problem requires the NFIP to understand (1) what drives the demand for flood insurance so that it can be increased, (2) how risk factors contribute towards large flood insurance payouts so that effective risk reduction policies can be planned, and (3) how to predict the future flood insurance payouts so that the NFIP can be financially prepared. This research has answered these three fundamental questions by developing empirical models based on historical data. To answer the first question, this research has developed a propensity score-based causal model that analyzed one of the key components that influences the demand for flood insurance – the availability of post-disaster government assistance. It was found that the availability of the federal payout in a county in a year increased the number of flood insurance policies by 5.2% and the total insured value of the policies by 4.6% in the following year. Next, this research has developed Mixed Effects Regression model that quantified the causal relationships between the annual flood insurance payout in a county and flood related risk factors such as flood exposure, infrastructure vulnerability, social vulnerability, community resilience, and the number of mobile homes in the county. Based on the derived causal estimates, it was predicted that climate change, which is expected to increase flood exposure in coastal counties, will increase the annual NFIP payout in New Orleans, Louisiana by $2.04 billion in the next 30 years. Lastly, to make the NFIP financially prepared for future payouts, this research has developed a predictive model that can predict the annual NFIP payout in a county with adequate predictive accuracy. The predictive model was used to predict the NFIP payout for 2021 and it was able to predict that with a 9.8% prediction error. The outcomes of this research create new knowledge to inform policy decisions and strategies aimed at fortifying the NFIP. This includes strategies such as flood protection infrastructure, tailored disaster assistance, and other interventions that can bolster flood insurance uptake while mitigating the risk of substantial payouts. Ultimately, this research contributes to sustaining the NFIP's ability to provide vital flood insurance coverage to millions of Americans.</p>

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