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Beneficiation Of Himmetoglu And Beypazari Oil Shales By Flotation And Their Thermal Characterization As An Energy SourceAltun, Naci Emre 01 January 2006 (has links) (PDF)
Processing of Bolu-Himmetoglu (Type I Kerogen) and Ankara-Beypazari (Type II Kerogen) oil shales by flotation techniques were investigated for achieving clean solid fuel substitutes. Materials characterization was done through mineralogical, XRD and FTIR analyses. Flotation responses of the samples were tested with non-ionizing and ionizing collectors of cationic and anionic types. The effects of the collector dosage and pulp pH on cleaning were determined. Other important flotation parameters, conditioning time, flotation time, pulp density, particle size and frother dosage were encountered using a statistical approach, through a full two level factorial experimental design. An advanced flotation procedure, assisted by ultrasonic application, was developed for further improvement in flotation performance. The effects of cleaning on thermal characterstics and combustion kinetics were evaluated with Differential Scanning Calorimetry and ASTM methods while the changes in the emission profiles were assessed using Effluent Gas Analysis.
Himmetoglu sample was characterized as a carbonate and organic rich humic oil shale with XRD and FTIR analyses while Beypazari oil shale involved significant carbonate and clay minerals and exhibited a fulvic character with a poor organics content. Reverse flotation with amine acetates provided the most effective means of cleaning with Himmetoglu oil shale. Ash was decreased from 34.76 % to 23.52 % with a combustible recovery of 83.57 % using 800 g/ton Flotigam CA at natural pH and the calorific value increased from 4312 kcal/kg to 5010 kcal/kg. Direct flotation with amines was most effective for Beypazari oil shale cleaning. Using Armoflote 17, ash was reduced from 69.88 % to 53.10 % with 58.64 % combustible recovery using 800 g/ton Armoflote 17 at natural pulp pH and the calorific value of the sample increased from 876 kcal/kg to 2046 kcal/kg. Following optimization, ash of Himmetoglu oil shale decreased to 16.81 % with 84.10 % combustible recovery and calorific value increased to 5564 kcal/kg. For Beypazari oil shale ash decreased to % 48.42 with 59.17 % combustible recovery and the calorific value increased to 2364 kcal/kg. Ultrasonic pre-treatment before flotation further decreased the ash of Himmetoglu sample to 11.82 % with 82.66 % combustible recovery at 15 minutes pre-conditioning time and 50 % power level. For Beypazari oil shale, ash decreased to 34.76 % with 64.78 % combustible recovery after 15 minutes pre-treatment time at 70 % power level. Comparative XRD spectra and SEM analyses revealed that the extent of mineral matter removal relied on the flotation performance.
The thermal indicators considerably improved after cleaning and the extent of improvement increased with a decrease in the ash of the concentrates. Kinetic analysis showed the favorable effect of inorganics removal on the effectiveness and easiness of combustion and activation energies decreased after cleaning for both oil shales. The contributions of cleaning on the effectiveness of combustion were also revealed by the increases in the emission rates and total CO2 and CO emission amounts. CO2 emissions due to mineral matter decomposition and harmful SO2 emissions apparently decreased as a consequence of the cleaning of the undesired inorganic contituents and potentially cleaning components. Results of the cleaning and thermal analysis sudies revealed that it was possible to achieve a clean energy source alternative from oil shales through flotation and a significant potential can be anticipated for future use of oil shales as a cost effective and environmental friendly solid fuel substitute in view of Turkey& / #8217 / s great oil shale reserves.
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Adat Iban: a living traditional wisdom?Edward, Ronnie 22 December 2020 (has links)
Adat Iban are Indigenous law of the Iban people of Sarawak, Malaysia. This dissertation
explores the wisdom of Adat Iban and examines whether the Adat and the underlying wisdom are living Adat. Currently, the interpretation, application, and enforcement of the Adat are basically following the Iban ancestors’ practices and complying with spiritual obligations. This practice provides very little legal reasoning which obscures the rationales and wisdom of Adat. Under such situation, the flux of socio-economic and political developments and social changes that have been taking place in the Iban communities impinges the relevance and significance of Adat in the regulation of social relations of the communities. This study presents a reinterpretation and/or re-evaluation of Adat Iban to elucidate the rationales and wisdom of Adat Iban. This approach could provide legal reasonings which could rejuvenate the relevance of Adat and make Adat to become more comprehensible law of general application to the changing Iban communities. “Wisdom” encompasses Iban autochthonous knowledge, ideas, experiences, judgements, and spiritual principle that evolved into Adat. Wisdom is the quality that enables an Adat to be utilised to bring about beneficial or noble purpose, or justice. The study contends that there is wisdom in most Adat Iban. However, the social changes and modernisation that are taking place in most Iban communities raise the question of whether the Adat and the underlying wisdom are living Adat. A living Adat is one that is dynamic and flexible and constantly adjusting and adapting to the new or changing social situations. This study
concludes that most Adat Iban have the potential to be living Adat and continue to be relevant for the regulation of Iban communities. However, the survival, development, and continuing relevance of Adat Iban depend on the Iban. / Graduate / 2021-11-18
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EVOLUTIONARY IMPLICATIONS OF NEONICOTINOID EXPOSURE TO MAYFLIES OF THE HEPTAGENIIDAEDaniel R Rackliffe (10675833) 26 April 2021 (has links)
<p>Mayflies are important macroinvertebrate members of steam
communities and are highly sensitive to agricultural insecticides. In this
dissertation I sought to explore whether Heptageniidae<i> </i>mayflies in
Indiana have evolved greater tolerance to clothianidin, a neonicotinoid
insecticide that has been widely applied over the predominant corn and soybean
crops of the state for the last 20 years. Over the five chapters of this
dissertation, I investigate different aspects of the effects of clothianidin on
mayfly populations. First, I collected mayfly populations from streams around
the state across a gradient of agricultural landscape to see if proximity to corn
and soybean crops was associated with tolerance to the insecticide. I found
significant variation in tolerance between the populations but only connected
it to land use for one species and one insecticide. Second, I investigated the
potential for increases in predation rates due to exposure to low concentrations
of clothianidin by both a vertebrate and invertebrate predator. Sublethal
exposure did increase the risk of predation by the invertebrate predator but
not the vertebrate. Third, I collected four populations of mayflies and placed
them in a common stream which is heavily impacted by agricultural runoff. The
most tolerant of the four populations had the highest survival rates and was
native to the polluted stream, suggesting that it was best adapted to the local
conditions. Finally, the last chapter is a discussion of the factors
influencing the evolution of contaminant tolerance, the implications for
biomonitoring, and a series of recommendations for incorporating evolved
tolerance into biomonitoring practices. Collectively, this work suggests that
the lethal and sublethal effects of clothianidin exposure create conditions
suitable for the evolution of tolerance in Heptageniid mayflies. While there are
already differences in tolerance between populations, it seems likely that
mayfly pesticide tolerance will continue to increase as pesticides continue to impact
aquatic ecosystems. </p>
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Nové gelové elektrolyty / New gel electrolytesSumka, Martin January 2016 (has links)
This master´s thesis deals with the properties of gel polymer electrolytes, brief characteristics of other types of electrolytes and materials that are used for preparing polymer electrolytes. The thesis explains the use of the gel electrolytes in practice, the current conduction in the electrolytes and the properties of ionic liquids, and flame retardants. This thesis also focuses on methods of measurement of mechanical properties of gel polymer electrolytes. The practical part is focused on preparation of methacrylate gel electrolytes and their modifications with the use of flame retardant - triethyl phosphate (TEP) and ionic liquid - 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (Emim TFSI). In this part there are evaluations of their potential funcionality (potential window) and specific conductance conductivity using the method LSV (linear sweep voltammetry) and impedance spectroscopy. The practical part also includes a thermal analysis of selected samples by TGA, DTA and EGA methods.
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Proces d'alienation de l'intellectuel dans les romans sub-Saharaiens Francophones : Xala D'O. sembene, le pacte de Sang de P.N. Nkashama et L'Histoire du fou de M. Beti / Denouncing the alienation of the intellectual elite in sub-Saharan Francophone novels : Xala by O. Sembene, le Pacte de sang by P.N. Nkashamba, and L'Histoire du fou by M. BetiNtita, Samuel Beya 05 1900 (has links)
Text in French, with abstracts in French and English / Au lendemain des indépendances africaines, les écrivains tentent de dénoncer, sinon
l’aliénation des intellectuels, du moins ce que le peuple désignait sous ce terme dans les excolonies françaises et belges. Le recours fréquent, dans la construction du récit, à la
thématique de la faute de l’intellectuel se présente comme résultat d’un manquement au rôle
qui lui revient. Pour mener à bien notre enquête, la théorie utilisée est l’Analyse de contenu
thématique (A.C.T.) de Pierre Lannoy. Ce modèle aidera à cerner tout ce qui menace
l’équilibre de l’édifice social. Cependant l’étude de l’aliénation des intellectuels a montré
que l’émergence d’une crise semblable relève d’une série de causes complexes. Sa
compréhension fait appel à de multiples champs scientifiques : sociologie, psychologie,
économie, […] La seule solution est le compromis pour tous. C’est une vaine prétention que
de vouloir établir ici un bilan exhaustif : l’étude de l’image de l’intellectuel ne peut qu’être évolutive. / In the aftermath of African independence, writers tried to denounce, if not the alienation of
intellectuals, at least what people meant by this term in the former French and Belgian
colonies. Frequent recourse to the theme of the fault of the intellectual in the construction of
the narrative is presented as the result of a failure to fulfil the role that was assigned to him.
To carry out our investigation, the theory used is Pierre Lannoy's Thematic Content Analysis
(T.C.A.). This model will help to identify anything that threatens the balance of the social
edifice. However, the study of the alienation of intellectuals has shown that the emergence
of a similar crisis is due to a series of complex causes. Its understanding involves multiple
scientific fields: sociology, psychology, economics, [...] The only solution is compromise for
all. It is a vain claim to want to establish an exhaustive assessment here: the study of the image of the intellectual can only be evolutionary. / Classics and World Languages / D. Litt. et Phil. (French)
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Point-to-Multipoint Services on Fifth-Generation Mobile NetworksBarjau Estevan, Carlos Salvador 20 January 2023 (has links)
[ES] Esta disertación cubre el estado del arte en LTE eMBMS Release 14, también conocido como Enhanced Television Services (ENTV). ENTV trajo un conjunto de mejoras, tanto a nivel radio como a nivel de núcleo, que transformó a eMBMS en un estándar de televisión terrestre completo. La última versión de esta tecnología se denomina LTE-based 5G Broadcast; pero no usa New Radio ni el núcleo 5G. Para proveer una solución nativa 5G de servicios punto-a-multipunto, hubo investigación en entornos acad\'emicos y colaboraciones público-privada. La iniciativa más notable en este aspecto fue el proyecto del Horizon 2020 5G-Xcast, que transcurrió de 2017 a 2019. 5G-Xcast produjo varias soluciones a nivel de arquitectura, desde la perspectiva de provisión de contenidos, nuevas funciones de red interoperables con el núcleo 5G, hasta modificaciones a la interfaz aire basada en New Radio. Los hallazgos del proyecto están descritos en esta tesis. La tesis incluye dos ejemplos de eMBMS aplicados a verticales diferentes, una para el uso de eMBMS en entornos industriales, y otra presentando eMBMS como un sistema SAP.
Incluir servicios punto-a-multipunto como un modo adicional celular trae algunos desafíos, como ya mostró la estandarización de eMBMS: las redes de radiodifusión terrestre y las redes celulares son muy distintas entre ellas. Encontrar una forma de onda viable para ambas infraestructuras es complejo. Esta tesis ofrece un punto de vista distinto al problema: un escenario de colaboración entre cadenas televisivas y operadores móviles, donde la infraestructura de radiodifusión y móvil son compartidas. Este concepto se ha definido como Convergence of Terrestrial and Mobile Networks. Las tecnologías elegidas para converger son ATSC 3.0 y 5G, usando el Advanced Traffic Steering, Switching and Splitting (ATSSS). ATSSS está compuesto de una serie de procedimientos, interfaces, funciones de red, para permitir el uso compartido de un acceso 3GPP con uno non-3GPP, como Wi-Fi. Sin embargo, el uso de ATSSS para juntar radiodifusión y celular no es trivial, ya que ATSSS no fue dise\~ado para enlaces radio unidireccionales como ATSC 3.0. Estas limitaciones son descritas en detalle, y una propuesta para solventarlas tambi\'en está incluida. La solución se basa en Quick UDP Internet Connections (QUIC), y se usa como ejemplo para la provisión de Convergent Services (File Repair y Video Offloading).
La tesis concluye con una descripción de Release 17 5MBS, con los nuevos conceptos introducidos. 5MBS es capaz de cambiar entre unicast, multicast y broadcast; dependiendo del servicio, la ubicación geográfica de los usuarios, y las capacidades de la infraestructura móvil involucradas. Para evaluar 5MBS, se ha realizado un estudio de prestaciones, basado en comunicaciones multicast dentro del núcleo de red 5G. Este prototipo 5MBS forma parte del laboratorio VLC Campus 5G, y utiliza el software comercial Open5GCore como base del desarrollo. El modelo de sistema para la experimentación esta formado por un servidor de vídeo, que se conecta al Open5GCore y a las funciones de red mejoradas con funcionalidades 5MBS. Estas funciones de red envían el contenido mediante punto-a-multipunto a un entorno radio y terminales simulados. Los resultados obtenidos resaltan el objetivo principal de la tesis: las comunicaciones punto-a-multipunto son una solución escalable para el envío de contenido multimedia en directo. / [CA] Aquesta dissertació cobreix capdavanter en LTE eMBMS Release 14, també
conegut com Enhanced Television Services (ENTV). ENTV va portar un conjunt
de millores, tant a nivell de ràdio com a nivell de nucli, que va transformar el eMBMS en un estàndard de televisió terrestre complet. La última
versió d'aquesta tecnologia es denomina LTE-based 5G Broadcast; però no fa servir
New Ràdio ni el nucli 5G. Per a proveir una solució nativa 5G de serveis punt-a-multipunt, va haver-hi investigació en entorns acadèmics i col·laboracions
pública i privada. La iniciativa més notable en aquest aspecte va ser el projecte
del Horizon 2020 5G-Xcast, que va transcórrer del 2017 a 2019. 5G-Xcast va produir
diverses solucions a nivell d'arquitectura, des de la perspectiva de provisió de
continguts, noves funcions de xarxa interoperables amb el nucli 5G, fins a modificacions
a la interfície aire basada en New Radio. Les troballes del projecte
estan descrits en aquesta tesi. La tesi inclou dos exemples de eMBMS aplicats
a verticals diferents, una per a l'ús de eMBMS en entorns industrials, i
una altra presentant eMBMS com un sistema SAP.
Incloure serveis punt-a-multipunt com una manera addicional cel·lular duu
alguns desafiaments, com ja va mostrar l'estandardització de eMBMS: les xarxes de
radiodifusió terrestre i les xarxes cel·lulars són molt diferents entre elles. Trobar
una forma d'ona viable per a totes dues infraestructures és complex.
Aquesta tesi ofereix un punt de vista diferent al problema: un escenari de col·laboració entre cadenes televisives i operadors mòbils, on la infraestructura
de radiodifusió i mòbil són compartides. Aquest concepte s'ha definit com
Convergence of Terrestrial and Mobile Networks. Les tecnologies triades per a
convergir són ATSC 3.0 i 5G, usant el Advanced Traffic Steering, Switching
and Splitting (ATSSS). ATSSS està compost d'una sèrie de procediments,
interfícies, funcions de xarxa, per a permetre l'ús compartit d'un accés
3GPP amb un non-3GPP, com a Wi-Fi. No obstant això, l'ús de ATSSS per a
adjuntar radiodifusió i cel·lular no és trivial, ja que ATSSS no va ser dissenyada
per a per a enllaços ràdio unidireccionals com ATSC 3.0. Aquestes limitacions són
descrites detalladament, i una proposta per a solucionar-les també està inclosa.
La solució es basa en Quick UDP Internet Connections (QUIC), i s'usa
com a exemple per a la provisió de Convergent Services (File Repair i Vídeo
Offloading).
La tesi conclou amb una descripció de Release 17 5MBS, amb els nous
conceptes introduïts. 5MBS és capaç de canviar entre unicast, multicast i
broadcast; depenent del servei, la ubicació geogràfica dels usuaris, i
les capacitats de la infraestructura mòbil involucrades. Per a avaluar 5MBS,
s'ha realitzat un estudi de prestacions, basat en comunicacions multicast
dins del nucli de xarxa 5G. Aquest prototip 5MBS forma part del laboratori
VLC Campus 5G, i utilitza el programari comercial Open5GCore com a base
del desenvolupament. El model de sistema per a l'experimentació està format
per un servidor de vídeo, que es connecta al Open5GCore i a les funcions
de xarxa millorades amb funcionalitats 5MBS. Aquestes funcions de xarxa envien el
contingut mitjançant punt-a-multipunt a un entorn ràdio i terminals simulats.
Els resultats obtinguts ressalten l'objectiu principal de la tesi: les
comunicacions punt-a-multipunt són una solució escalable per a l'enviament
de contingut multimèdia en directe. / [EN] This dissertation covers the state-of-the-art in LTE eMBMS Release 14, also known as Enhanced Television Services (ENTV). ENTV provided a suite of radio and core enhancements that made eMBMS into a viable terrestrial broadcast standard. The latest iteration of this technology is known as LTE-based 5G Broadcast; even though it is not New Radio or 5G Core based. To bridge this gap, research efforts by academia, public and private enterprises evaluated how to provide a 5G-based solution for point-to-multipoint services. The most notable effort in this regard is the Horizon 2020 project 5G-Xcast, which ran from 2017 to 2019. 5G-Xcast provided several architectural solutions, from the content delivery perspective down to air interface specifics; providing new waveforms based on New Radio and Network Functions interoperable with a Release 15 5G Core. The findings are summarized in this thesis. Two examples of eMBMS applied to different verticals are included in the thesis, one for the use of eMBMS in industrial environments, and the other using eMBMS as a PWS technology.
Providing point-to-multipoint services as another cellular service poses some problems, as the standardization process of eMBMS showed: the broadcast infrastructure is different than the cellular one. Having a waveform that is suited for both scenarios is a difficult endeavour. The thesis provides a new perspective into this problem: Having existing Terrestrial Broadcast standards and infrastructure be the point-to-multipoint solution of 5G, where mobile operators and broadcasters collaborate together. This is defined in the dissertation as Convergence of Terrestrial and Mobile Networks. The technologies chosen to be converged together were ATSC 3.0 and 5G; using the existing Release 16 framework known as Advanced Traffic Steering, Switching and Splitting (ATSSS). ATSSS is a series of procedures, interfaces, new Network Functions, to allow the joint use of a 3GPP Access Network alongside a non-3GPP one, like Wi-Fi. However, the use of ATSSS for cellular plus broadcast brings challenges, as the ATSSS technology was not designed to be used with a unidirectional access network like ATSC 3.0. These limitations are described in detail, and an architectural proposal that overcomes the limitations is proposed. This solution is based on Quick UDP Internet Connections (QUIC), and how to provide Convergent Services (i.e File Repair and Video Offloading) is shown.
The thesis concludes with a description of Release 17 5MBS, including the new concepts introduced. 5MBS features the capacity of switching between unicast, multicast and broadcast; depending on the service addressed, the geographical location of the users, and the capability of the RAN infrastructure targeted. In order to evaluate 5MBS, a performance study of the use of multicast inside the 5G Core has been carried out. The 5MBS prototype was developed as part of the VLC Campus 5G laboratory, using the commercial software Open5GCore which provides the libraries and Network Functions to deploy your own 5G Private Network in testing environments. The system model of the experiment is formed by a video server, connected to the Open5GCore and the 5MBS enhanced functions; which will deliver the content to an emulated RAN environment hosting virtual gNBs and devices. The results obtained reinforce the objective of the thesis, positioning point-to-multipoint as a scalable way to deliver live content. / Research projects: 5G-Xcast: Broadcast and Multicast Communication Enablers for the
Fifth-Generation of Wireless Systems (H2020 No 761498); 5G-TOURS: SmarT mObility, media and e-health for toURists and citizenS (H2020 No 856950); FUDGE-5G: FUlly DisinteGrated private nEtworks for 5G verticals (H2020 No 957242). / Barjau Estevan, CS. (2022). Point-to-Multipoint Services on Fifth-Generation Mobile Networks [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/191408
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