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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.
291

Réponse des communautés microbiennes du sol à l'apport de résidus de culture : influence des pratiques agricoles et lien avec le fonctionnement biologique du sol / Response of soil bacterial communities to the incorporation of crop residues : influence of agricultural practices and link with the soil biological process

Pascault, Noémie 13 July 2010 (has links)
A l’échelle de l’agro-écosystème, la productivité primaire est sous la dépendance du recyclage des matières organiques du sol (MOS) par l’action des organismes indigènes décomposeurs, qui minéralisent les composés organiques libérant ainsi les nutriments nécessaires à la croissance végétale. A une échelle plus globale, le recyclage des MOS détermine les flux de carbone entre le sol et l’atmosphère, avec des conséquences majeures sur la qualité de l’environnement et les changements globaux. Malgré le rôle central des microorganismes indigènes dans ces processus, la composante microbienne est encore mal connue et souvent considérée comme une boîte noire en termes de diversité et de fonctionnalité. Par conséquent, pour mieux comprendre et prédire l’évolution des MOS et donc les flux de carbone (C) dans les agro-écosystèmes, il est nécessaire de mieux connaitre les populations et les mécanismes microbiens impliqués dans leur dégradation et transformation. Dans ce contexte, l’objectif de cette thèse était de progresser dans la connaissance de la réponse des communautés microbiennes telluriques à l’apport de résidus de culture. Cette réponse des communautés microbiennes a été abordée en termes de (i) succession des populations impliquées dans les processus de dégradation de ces MOF (matières organiques fraîches), (ii) lien avec leur fonction de dégradation et répercussion sur la dynamique des matières organiques, et (iii) rôle dans les processus de stockage/déstockage du carbone via les processus de « priming effect ». Différents paramètres pouvant moduler la dégradation des résidus et la dynamique des communautés ont été pris en compte : modalité d’apport des résidus (pratiques culturales), qualité biochimique des résidus (différentes espèces végétales), et température. La stratégie globale de recherche développée repose sur des expérimentations de terrain et au laboratoire impliquant différentes échelles spatiales (du microcosme de sol à la parcelle agronomique) et temporelles (du temps de génération microbien aux cycles culturaux). La réponse des communautés microbiennes à l’apport de résidus a été évaluée par l’utilisation de méthodes moléculaires permettant de caractériser sans a priori la diversité des microorganismes du sol (empreintes moléculaires, clonage/séquençage, séquençage haut débit). En parallèle, un suivi quantitatif et qualitatif de la matière organique du sol, par des méthodes de biochimie ou de spectroscopie, a été réalisé afin d’établir le lien entre la dynamique des communautés microbiennes et le devenir de la matière organique dans le sol. Les deux premiers chapitres du manuscrit portent sur des expérimentations réalisées au terrain (conditions naturelles) afin d’évaluer l’influence de la localisation des résidus (résidus de blé incorporés vs. laissés en surface ; site expérimentale INRA Mons) d’une part et d’autre part de la qualité biochimique des résidus (résidus de blé, colza et luzerne incorporés, site expérimentale INRA Epoisses) sur la dynamique des communautés microbiennes du sol. Les résultats obtenus mettent en évidence une forte influence de la localisation comme de la qualité biochimique des résidus sur les successions de populations microbiennes induites suite à l’apport. Des populations/groupes microbiens stimulés spécifiquement dans chaque modalité ont été identifiés. Les résultats de diversité ont été mis en regard des dynamiques de décomposition des résidus, afin de faire le lien entre les successions de populations et l’évolution des ressources trophiques. La troisième partie du travail correspond à une expérimentation en conditions contrôlées (microcosmes de sol) nous permettant de coupler des outils moléculaires et isotopiques (ADN-SIP) pour cibler spécifiquement les populations microbiennes activement impliquées dans la dégradation des résidus de culture - etc / The effect of the location of wheat residues (soil surface vs. incorporated in soil) on their decomposition and on soil bacterial communities was investigated by the means of a field experiment. Bacterial-Automated Ribosomal Intergenic Spacer Analysis (B-ARISA) of DNA extracts from residues, detritusphere (soil adjacent to residues), and bulk soil evidenced that residues constitute the zone of maximal changes in bacterial composition. However, the location of the residues influenced greatly their decomposition and the dynamics of the colonizing bacterial communities. Sequencing of 16S rRNA gene in DNA extracts from the residues at the early, middle, and late stages of degradation confirmed the difference of composition of the bacterial community according to the location. Bacteria belonging to the -subgroup of proteobacteria were stimulated when residues were incorporated whereas the -subgroup was stimulated when residues were left at the soil surface. Moreover, Actinobacteria were more represented when residues were left at the soil surface. According to the ecological attributes of the populations identified, our results suggested that climatic fluctuations at the soil surface select populations harboring enhanced catabolic and/or survival capacities whereas residues characteristics likely constitute the main determinant of the composition of the bacterial community colonizing incorporated residues. Microbial communities are of major importance in the decomposition of soil organic matter. However, the identities and dynamics of the populations involved are still poorly documented. We investigated, in a eleven-month field experiment, how the initial biochemical quality of crop residues could lead to specific decomposition patterns, linking biochemical changes undergone by the crop residues to the respiration, biomass and genetic structure of the soil microbial communities. Wheat, alfalfa and rape residues were incorporated into the 0-15 cm layer of the soil of field plots by tilling. Biochemical changes in the residues occurring during degradation were assessed by near infrared spectroscopy (NIRS). Qualitative modifications in the genetic structure of the bacterial communities were determined by Bacterial-Automated Ribosomal Intergenic Spacer Analysis (B-ARISA). Bacterial diversity in the three crop residues at early and late stages of decomposition process was further analyzed from a molecular inventory of the 16S rDNA. The decomposition of plant residues in croplands was shown to involve specific biochemical characteristics and microbial communities dynamics which were clearly related to the quality of the organic inputs. Decay stage and seasonal shifts occurred by replacement of copiotrophic populations/bacterial groups such as proteobacteria successful on younger residues with those successful on more extensively decayed material such as Actinobacteria. However, relative abundance of proteobacteria depended greatly on the composition of the residues, with a gradient observed from alfalfa to wheat, suggesting that this bacterial group may represent a good indicator of crop residues degradability and modifications during the decomposition process...
292

On Traffic Analysis of 4G/LTE Traffic

Caldwell, Sean W. 21 September 2021 (has links)
No description available.
293

Implementace protokolu SIP / SIP Protocol Implementation

Dušek, Martin January 2011 (has links)
This Master’s thesis deals in detail with the SIP protocol – a method of communication between two entities, various types of transmitted messages and their content. Few SIP libraries are introduced and two of them are used for development of an application for audio/video conference-calls. Compilation of OPAL and PTlib libraries for Windows 7 Professional (64bit) is described, and problems resulting from lack of information provided by authors. New improved “how to build” is presented. At the end, paper focuses on several ways of development of mentioned application.
294

Vizualizace objemových dat pomocí volume renderingu / 3D Volume Rendering Data Visualization

Němeček, Pavel January 2010 (has links)
The first part of this project is focused on theoretical analysis of methods for rendering volume data. Both methods are analyzed showing the volume data using triangle mesh, and methods for direct volume rendering. Ray Casting is presented in detail. Possible way of its realization using graphics card is the subject of implementation part. The paper presents several methods that could be applied to ray casting and achieve different results of visualization of the same data. The work also aims to create a  graphical user interface that allows interactive visualizations.
295

Hlasový dialogový systém ve webovém prohlížeči pro demonstrační účely / Voice Dialog System in Web Browser for Demonstration Purposes

Vlček, Pavol January 2021 (has links)
Cieľom práce je navrhnúť a vytvoriť hlasom ovládaného asistenta(voicebota), ktorý bude ľahko nasaditeľný na webovú stránku. Používateľom tak bude poskytnutý moderný spôsob, ako prirodzene komunikovať cez internetový prehliadač. Hlavný dôraz je kladený na synchronizáciu medzi hlasovým asistentom a obsahom na webovej stránke. Synchronizácia je dosiahnutá obojsmerným prenosom hlasu a textových príkazov medzi klientom a serverom. Na to je použitá technológia WebRTC v kombinácií so signalizačným protokolom SIP. Práca sa zaoberá oblasťami ako VoIP telefonovanie, počítačové siete a strojové učenie(proprietárne rečové technológie od Phonexie). Benefitom nasadenia hlasového asistenta je zníženie nákladov na odchádzajúce hovory pre klientov, odľahčenie agentov na call centrách pri odpovedaní na často kladené otázky a zvýšenie záujmu zákazníkov vďaka použitiu nových technológií.
296

Facteurs de risque de mortalité des enfants à l’initiation de la thérapie de remplacement rénal aux soins intensifs

Morissette, Geneviève 08 1900 (has links)
Introduction : La mortalité associée à l’insuffisance rénale aiguë (acute kidney injury ‘’AKI’’) aux soins intensifs pédiatriques (SIP) dépasse les 50%. Des études antérieures sur la thérapie de remplacement rénal (TRR) ont fait ressortir plusieurs facteurs de risque de mortalité dont le syndrome de défaillance multiviscérale (SDMV) et la surcharge liquidienne ≥ 10 à 20% avant l’initiation de la TRR. L’objectif de cette étude était d’identifier les principaux facteurs de risque de mortalité à 28 jours après l’initiation de la TRR chez les patients atteints d’AKI aux SIP. Méthode : Il s’agit d’une étude de cohorte rétrospective aux SIP d’un centre tertiaire. Tous les enfants ayant reçus de la TRR continue ou de l’hémodialyse intermittente pour AKI, entre janvier 1998 et décembre 2014, ont été inclus. Les facteurs de risque de mortalité ont été préalablement identifiés par quatre intensivistes et deux néphrologues pédiatres et analysés à l’aide d’une régression logistique multivariée. Résultats : Quatre-vingt-dix patients ont été inclus. L’âge médian était de 9 [2-14] ans. La principale indication d’initiation de la TRR était la surcharge liquidienne (64,2%). La durée médiane d’hospitalisation aux SIP était de 18,5 [8,0-31,0] jours. Quarante patients (44,4%) sont décédés dans les 28 jours suivant l’initiation de la TRR et quarante-cinq (50,0%) avant la sortie des SIP. Le score de PELOD ≥ 20 (OR 4,66 ; 95%CI 1,68-12,92) et la surcharge liquidienne ≥ 15% (OR 9,31; 95%CI 2,16-40,11) à l’initiation de la TRR étaient associés de façon indépendante à la mortalité. Conclusion : Cette étude a permis de faire ressortir deux facteurs de risque de mortalité à 28 jours à l’initiation de la TRR : la surcharge liquidienne et la sévérité du SDMV mesurée par le score de PELOD. / Introduction: Mortality rate associated with acute kidney injury (AKI) in pediatric intensive care units (PICU) exceeds 50%. Prior studies on renal replacement therapy (RRT) have highlighted different mortality risk factors including the presence of a multiple organ dysfunction syndrome (MODS) and fluid overload ≥ 10 to 20% before starting RRT. The aim of this study was to identify most important risk factors of 28-day mortality in patients with AKI at RRT initiation in PICU. Methods: We conducted a retrospective cohort study in a tertiary care pediatric center. All critically ill children who underwent acute continuous RRT or intermittent hemodialysis for AKI between January 1998 and December 2014 were included. A case report form was developed and specific risk factors were identified by a panel of four pediatric intensivists and two nephrologists. Risk factors analysis was made using logistic regression in SPSS and SAS software. Results: Ninety patients were included. The median age was 9 [2-14] years. The most common indication for RRT initiation was fluid overload (FO) (64.2%). The median PICU length of stay was 18.5 [8.0-31.0] days. Forty of the 90 patients (44.4%) died within 28 days after RRT initiation and forty-five (50.0%) died before PICU discharge. In a multivariate logistic regression analysis, a PELOD score ≥ 20 (OR 4.66; 95%CI 1.68-12.92) and percentage of FO ≥ 15% (OR 9.31; 95%CI 2.16-40.11) at RRT initiation were independently associated with mortality. Conclusion: This study suggests that fluid overload and severity of MODS measured by PELOD score are two risk factors of 28-day mortality in PICU patients on RRT.
297

Le mode de ventilation neurally adjusted ventilatory assist (NAVA) est faisable, bien toléré, et permet la synchronie entre le patient et le ventilateur pendant la ventilation non invasive aux soins intensifs pédiatriques : étude physiologique croisée

Ducharme-Crevier, Laurence 08 1900 (has links)
Introduction: La ventilation non invasive (VNI) est un outil utilisé en soins intensifs pédiatriques (SIP) pour soutenir la détresse respiratoire aigüe. Un échec survient dans près de 25% des cas et une mauvaise synchronisation patient-ventilateur est un des facteurs impliqués. Le mode de ventilation NAVA (neurally adjusted ventilatory assist) est asservi à la demande ventilatoire du patient. L’objectif de cette étude est d’évaluer la faisabilité et la tolérance des enfants à la VNI NAVA et l’impact de son usage sur la synchronie et la demande respiratoire. Méthode: Étude prospective, physiologique, croisée incluant 13 patients nécessitant une VNI dans les SIP de l’hôpital Ste-Justine entre octobre 2011 et mai 2013. Les patients ont été ventilés successivement en VNI conventionnelle (30 minutes), en VNI NAVA (60 minutes) et en VNI conventionnelle (30 minutes). L’activité électrique du diaphragme (AEdi) et la pression des voies aériennes supérieures ont été enregistrées pour évaluer la synchronie. Résultats: La VNI NAVA est faisable et bien tolérée chez tous les enfants. Un adolescent a demandé l’arrêt précoce de l’étude en raison d’anxiété reliée au masque sans fuite. Les délais inspiratoires et expiratoires étaient significativement plus courts en VNI NAVA comparativement aux périodes de VNI conventionnelle (p< 0.05). Les efforts inefficaces étaient moindres en VNI NAVA (résultats présentés en médiane et interquartiles) : 0% (0 - 0) en VNI NAVA vs 12% (4 - 20) en VNI conventionnelle initiale et 6% (2 - 22) en VNI conventionnelle finale (p< 0.01). Globalement, le temps passé en asynchronie a été réduit à 8% (6 - 10) en VNI NAVA, versus 27% (19 - 56) et 32% (21 - 38) en périodes de VNI conventionnelle initiale et finale, respectivement (p= 0.05). Aucune différence en termes de demande respiratoire n’a été observée. Conclusion: La VNI NAVA est faisable et bien tolérée chez les enfants avec détresse respiratoire aigüe et permet une meilleure synchronisation patient-ventilateur. De plus larges études sont nécessaires pour évaluer l’impact clinique de ces résultats. / Introduction: The need for intubation after noninvasive ventilation (NIV) failure is frequent in the pediatric intensive care unit (PICU). One reason is patient-ventilator asynchrony during NIV. Neurally adjusted ventilatory assist (NAVA) is a mode of ventilation controlled by the patient’s neural respiratory drive. The aim of this study was to assess the feasibility and tolerance of NIV-NAVA in children and to evaluate its impact on synchrony and respiratory effort. Methods: This prospective, physiologic, crossover study included 13 patients requiring NIV in the PICU of Sainte-Justine’s Hospital from October 2011 to May 2013. Patients were successively ventilated in conventional NIV as prescribed by the physician in charge (30 minutes), in NIV-NAVA (60 minutes), and again in conventional NIV (30 minutes). Electrical activity of the diaphragm (EAdi) and airway pressure were simultaneously recorded to assess patient-ventilator synchrony. Results: NIV-NAVA was feasible and well tolerated in all patients. One patient asked to stop the study early because of anxiety related to the leak-free facial mask. Inspiratory trigger dys-synchrony and cycling-off dys-synchrony were significantly shorter in NIV-NAVA versus initial and final conventional NIV periods (both p< 0.05). Wasted efforts were also decreased in NIV-NAVA (all values expressed as median and interquartile values): 0 (0 - 0) in NIV-NAVA versus 12% (4 - 20) and 6% (2 - 22) in initial and final conventional NIV, respectively (p< 0.01). As a whole, total time spent in asynchrony was reduced to 8% (6 - 10) in NIV-NAVA, versus 27% (19 - 56) and 32% (21 - 38) in initial and final conventional NIV, respectively (p= 0.05). No difference in term of respiratory effort was noted. Conclusion: NIV-NAVA is feasible and well tolerated in PICU patients and allows improved patient-ventilator synchronization. Larger controlled studies are warranted to evaluate the clinical impact of these findings.
298

Stress and Microstructural Evolution During the Growth of Transition Metal Oxide Thin Films by PVD

Narayanachari, K V L V January 2015 (has links) (PDF)
System on Chip (SoC) and System in Package (SiP) are two electronic technologies that involve integrating multiple functionalities onto a single platform. When the platform is a single wafer, as in SOC, it requires the ability to deposit various materials that enable the different functions on to an underlying substrate that can host the electronic circuitry. Transition metal oxides which have a wide range of properties are ideal candidates for the functional material. Si wafer on which micro-electronics technology is widely commercialized is the ideal host platform. Integrating oxides with Si, generally in the form of thin films as required by microelectronics technology, is however a challenge. It starts with the fact that the properties of crystalline oxides to be exploited in performing various functions are direction dependent. Thus, thin films of these oxides need to be deposited on Si in certain crystallographic orientations. Even if a suitably oriented Si wafer surface were available, it does not always provide for epitaxial growth a critical requirement for controlling the crystalline orientation of thin films. This is because Si surface is covered by an amorphous oxide of Si (SiOx). Thus, during growth of the functional oxide, an ambience in which the Si itself will not oxidize needs to be provided. In addition, during thin film growth on either Si or SiOx surface stresses are generated from various sources. Stress and its relaxation are also associated with the formation and evolution of defects. Both, stress and defects need to be managed in order to harness their beneficial effects and prevent detrimental ones. Given the requirement of SoC technology and the problem associated, the research work reported in this thesis was hence concerned with the precise controlling the stress and microstructure in oxide thin films deposited on Si substrates. In order to do so a versatile, ultra high vacuum (UHV) thin film with a base pressure of 10-9 Torr was designed and built as part of this study. The chamber is capable of depositing films by both sputtering (RF & DC) and pulsed laser ablation (PLD). The system has been designed to include an optical curvature measurement tool that enabled real-time stress measurement during growth. Doped zirconia, ZrO2, was chosen as the first oxide to be deposited, as it is among the few oxides that is more stable than SiOx. It is hence used as a buffer layer. It is shown in this thesis that a change in the growth rate at nucleation can lead to (100) or (111) textured films. These two are among the most commonly preferred orientation. Following nucleation a change in growth rate does not affect orientation but affects stress. Thus, independent selection of texture and stress is demonstrated in YSZ thin films on Si. A quantitative model based on the adatom motion on the growth surface and the anisotropic growth rates of the two orientations is used to explain these observations. This study was then subsequent extended to the growth on platinized Si another commonly used Si platform.. A knowledge of the stress and microstructure tailoring in cubic zirconia on Si was then extended to look at the effect of stress on electrical properties of zirconia on germanium for high-k dielectric applications. Ge channels are expected to play a key role in next generation n-MOS technology. Development of high-k dielectrics for channel control is hence essential. Interesting stress and property relations were analyzed in ZrO2/Ge. Stress and texture in pulsed laser deposited (PLD) oxides on silicon and SrTiO3 were studied. It is shown in this thesis that stress tuning is critical to achieve the highest possible dielectric constant. The effect of stress on dielectric constant is due to two reasons. The first one is an indirect effect involving the effect of stress on phase stability. The second one is the direct effect involving interatomic distance. By stress control an equivalent oxide thickness (EOT) of 0.8 nm was achieved in sputter deposited ZrO2/Ge films at 5 nm thickness. This is among the best reported till date. Finally, the effect of growth parameters and deposition geometry on the microstructural and stress evolution during deposition of SrTiO3 on Si and BaTiO3 on SrTiO3 by pulsed laser deposition is the same chamber is described.
299

State-of-the-art practices being reported by the PRME champions group: a reference to advance education for sustainable development

Ghizzi, Mariana Reis de Assumpção 28 May 2018 (has links)
Submitted by Mariana Assumpcao (maghizzi@gmail.com) on 2018-08-29T03:35:46Z No. of bitstreams: 1 State-Of-The-Art Practices Being Reported by the PRME Champions Group - A Reference to Advance Education for Sustainable Development_Mariana Assumpcao_2018.pdf: 4548141 bytes, checksum: 8ed554ba741dffca269c8a36802c13ac (MD5) / Rejected by Simone de Andrade Lopes Pires (simone.lopes@fgv.br), reason: Prezada Mariana, Recebemos o seu trabalho na biblioteca mas será necessário fazer alguns ajustes. Estou encaminhando por e-mail as alterações necessárias. Por favor, faça as alterações e submeta novamente o trabalho na biblioteca digital. Atenciosamente Simone - SRA on 2018-08-30T20:17:31Z (GMT) / Submitted by Mariana Assumpcao (maghizzi@gmail.com) on 2018-08-31T19:26:18Z No. of bitstreams: 1 State-Of-The-Art Practices Being Reported by the PRME Champions Group - A Reference to Advance Education for Sustainable Development_Mariana Assumpcao_2018.pdf: 4547611 bytes, checksum: 49aad4c70da4e8b21919f40dcb9dec70 (MD5) / Rejected by Simone de Andrade Lopes Pires (simone.lopes@fgv.br), reason: Prezada Mariana, Recebemos o trabalho aplicado submetido a biblioteca digital, mas o trabalho não tem as alterações solicitadas. Por favor, submeta novamente o trabalho com as alterações. Atenciosamente, Simone de A Lopes Pires SRA on 2018-09-03T19:47:18Z (GMT) / Submitted by Mariana Assumpcao (maghizzi@gmail.com) on 2018-09-03T20:00:26Z No. of bitstreams: 1 State-Of-The-Art Practices Being Reported by the PRME Champions Group - A Reference to Advance Education for Sustainable Development_Mariana Assumpcao_2018.pdf: 4547611 bytes, checksum: 49aad4c70da4e8b21919f40dcb9dec70 (MD5) / Rejected by Simone de Andrade Lopes Pires (simone.lopes@fgv.br), reason: Boa Tarde Mariana. Por favor, verifique o trabalho que está submetendo. Continua subindo o arquivo errado. Atenciosamente, Simone de A Lopes Pires SRA on 2018-09-03T21:50:12Z (GMT) / Submitted by Mariana Assumpcao (maghizzi@gmail.com) on 2018-09-04T16:36:14Z No. of bitstreams: 1 State-Of-The-Art Practices Being Reported by the PRME Champions Group - A Reference to Advance Education for Sustainable Development_2018.pdf: 4552208 bytes, checksum: 88fc40ea635711c491b70fdfaa59faf9 (MD5) / Rejected by Simone de Andrade Lopes Pires (simone.lopes@fgv.br), reason: Boa Tarde Mariana, Verifiquei que não há no seu trabalho um resumo em português, Por favor, acrescente o resumo e submeta novamente o trabalho para liberação. Atenciosamente, Simone on 2018-09-04T18:03:54Z (GMT) / Submitted by Mariana Assumpcao (maghizzi@gmail.com) on 2018-09-04T19:01:49Z No. of bitstreams: 1 State-Of-The-Art Practices Being Reported by the PRME Champions Group - A Reference to Advance Education for Sustainable Development_2018.pdf: 4587968 bytes, checksum: 9f93d7aab79b6eeafed4e925d67c24f9 (MD5) / Approved for entry into archive by Simone de Andrade Lopes Pires (simone.lopes@fgv.br) on 2018-09-04T19:24:19Z (GMT) No. of bitstreams: 1 State-Of-The-Art Practices Being Reported by the PRME Champions Group - A Reference to Advance Education for Sustainable Development_2018.pdf: 4587968 bytes, checksum: 9f93d7aab79b6eeafed4e925d67c24f9 (MD5) / Approved for entry into archive by Suzane Guimarães (suzane.guimaraes@fgv.br) on 2018-09-05T13:01:10Z (GMT) No. of bitstreams: 1 State-Of-The-Art Practices Being Reported by the PRME Champions Group - A Reference to Advance Education for Sustainable Development_2018.pdf: 4587968 bytes, checksum: 9f93d7aab79b6eeafed4e925d67c24f9 (MD5) / Made available in DSpace on 2018-09-05T13:01:10Z (GMT). No. of bitstreams: 1 State-Of-The-Art Practices Being Reported by the PRME Champions Group - A Reference to Advance Education for Sustainable Development_2018.pdf: 4587968 bytes, checksum: 9f93d7aab79b6eeafed4e925d67c24f9 (MD5) Previous issue date: 2018-05-28 / This study aims to offer a diagnostic of the 'state-of-the-art' practices being reported throughout the Sharing Information Process (SIP) by the Champions Group, a group of schools that are signatories of the Principles of Responsible Management Education (PRME, a United Nations Global Compact initiative), committed to spearheading transformational change toward more socially and environmentally responsible leadership. The study also suggests an analytical model - based on qualitative research and documentary analysis – to define the study sample, investigate data, identify patterns, organise and codify a large amount of information within all reports searched. The analytical model represents a framework in which the result is a collection of practices being reported, functioning as a useful guide and practical reference for higher educational institutions – signatory or otherwise – when promoting or advancing transformational change in their business model. The framework could also be valuable for Graduate Schools – or even Primary Schools to High Schools – considering the urgency of the 2030 Agenda, especially its 4.7 target, referred to as 'An education for sustainable development and global citizenship'. / Este estudo propõe um diagnóstico do que seria o estado da arte das práticas sendo reportadas através dos relatórios SIP (Sharing Information Process) pelo Champions Group, um grupo de escolas de negócios que são signatárias do Principles of Responsible Management Education (PRME, uma iniciativa da Organização das Nações Unidas pelo Pacto Globa) e que se comprometeram a liderar mudanças transformacionais em direção a formação de lideranças mais responsáveis quanto a aspectos sociais e ambientais. O estudo também sugere um modelo analítico – baseado em pesquisa qualitativa a análise documental – para os processos de definição da amostra de pesquisa, de investigação de informações, identificação de padrões, organização e codificação de uma vasta quantidade de dados contidos no total de relatórios pesquisados. O modelo analítico representa um framework no qual o resultado corresponde a compilação das práticas reportadas, representando um guia útil e uma referência prática para instituições de ensino superior – signatárias ou não do PRME – quando estiverem promovendo ou avançando em mudanças transformacionais de seu modelo de negócio. O framework pode também ter valor para escolas de Graduação – ou mesmo para escolas de ensino fundamental e ensino médio – considerando a urgência destacada na Agenda 2030, especialmente na meta 4.7, que faz referência a 'uma educação para o desenvolvimento sustentável e para a cidadania global'.
300

THE DEVELOPMENT OF MASS SPECTROMETRIC METHODS FOR THE DETERMINATION OF THE CHEMICAL COMPOSITION OF COMPLEX MIXTURES RELEVANT TO THE ENERGY SECTOR AND THE DEVELOPMENT OF A NEW DEVICE FOR CHEMICALLY ENHANCED OIL RECOVERY FORMULATION EVALUATION

Katherine Elisabeth Wehde (8054564) 28 November 2019 (has links)
<p>This dissertation focused on the development of mass spectrometric methodologies, separation techniques, and engineered devices for the optimal analysis of complex mixtures relevant to the energy sector, such as alternative fuels, petroleum-based fuels, crude oils, and processed base oils. Mass spectrometry (MS) has been widely recognized as a powerful tool for the analysis of complex mixtures. In complex energy samples, such as petroleum-based fuels, alternative fuels, and oils, high-resolution MS alone may not be sufficient to elucidate chemical composition information. Separation before MS analysis is often necessary for such highly complex energy samples. For volatile samples, in-line two-dimensional gas chromatography (GC×GC) can be used to separate complex mixtures prior to ionization. This technique allows for a more accurate determination of the compounds in a mixture, by simplifying the mixture into its components prior to ionization, separation based on mass-to-charge ratio (<i>m/z</i>), and detection. A GC×GC coupled to a high-resolution time-of-flight MS was utilized in this research to determine the chemical composition of alternative aviation fuels, a petroleum-based aviation fuel, and alternative aviation fuel candidates and blending components as well as processed base oils.</p> Additionally, as the cutting edge of science and technology evolve, methods and equipment must be updated and adapted for new samples or new sector demands. One such case, explored in this dissertation, was the validation of an updated standardized method, ASTM D2425 2019. This updated standardized method was investigated for a new instrument and new sample type for a quadrupole MS to analyze a renewable aviation fuel. Lastly, the development and evaluation of a miniaturized coreflood device for analyzing candidate chemically enhanced oil recovery (cEOR) formulations of brine, surfactant(s), and polymer(s) was conducted. The miniaturized device was used in the evaluation of two different cEOR formulations to determine if the components of the recovered oil changed.

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