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Tomlinson, Andrew Michael. "Terahertz detection and electric field domains in multiple quantum wells." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302363.
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Hussain, Sakhawat. "Propriétés optiques et structurales de dispositifs luminescents contenant des puits quantiques (In,Ga)N à forte concentration en Indium et émettant dans le vert et le jaune." Thesis, Nice, 2014. http://www.theses.fr/2014NICE4123/document.
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Le but de cette thèse a été d'étudier les propriétés structurales et optiques de puits quantiques (PQs) d’InGaN/(Al)GaN obtenus par épitaxie en phase vapeur d’organométalliques. Différentes approches ont été mises en œuvre pour atteindre une émission dans le vert-jaune: la première utilisant une concentration d'indium ≥ 20% avec un PQ d’InGaN d’épaisseur <3.0 nm et vice versa. L'effet d'une couche d’encapsulation a également été étudié. Les techniques de microscopie à force atomique, de diffraction des rayons X, de photoluminescence (PL) et surtout de microscopie électronique à transmission (MET) ont été utilisées pour caractériser ces structures. Les épaisseurs des PQs et les compositions en indium ont été déterminées par le traitement numérique des franges de réseau dans les images MET haute résolution en section transverse. Un traitement original a été développé pour analyser quantitativement les fluctuations de l’épaisseur des PQs. L'analyse structurale des PQs ayant une composition en In élevé a montré que les défauts structuraux sont créés dans les PQs. La nature et la densité de ces défauts ont été déterminées et différents mécanismes pour leur formation ont été proposés. Il a également été montré que quelques monocouches d’encapsulation de GaN ou d’AlGaN déposées à la température de croissance des PQs limitent l’évaporation et/ou la diffusion d’indium. Ce procédé permet d’étendre la longueur d'onde d'émission avec une réduction de la dégradation de l'efficacité de la PL. Mon travail propose quelques pistes afin d'obtenir un bon compromis entre les paramètres contradictoires qui régissent l'efficacité des PQs émettant dans le vert-jauneThe goal of this thesis was to study the structural and optical properties of InGaN/(Al)GaN multiple QWs grown by metal organic chemical vapor deposition. Different approaches have been implemented to achieve green-yellow emission: high indium concentration (≥ 20%) with low InGaN QW thickness (< 3 nm) or vice versa. Moreover, the effect of a capping layer on top of the QWs has also been investigated. Atomic force microscopy, X-ray diffraction, room temperature photoluminescence (RTPL) and mainly transmission electron microscopy (TEM) techniques have been used to characterize these structures. The QW thicknesses and indium compositions have been determined by digital processing of lattice fringes in cross-sectional high resolution TEM images. An original treatment has been developed to analyze quantitatively InGaN QW thickness fluctuations. The structural analysis of multiple QWs with high indium composition has shown that structural defects are created in the QWs. The nature and the density of these defects have been determined and different mechanisms for their formation have been proposed. It has also been shown that a few monolayers of AlGaN or GaN capping layers deposited at the InGaN QW growth temperature prohibited indium evaporation and/or diffusion. It therefore helps to extend the emission wavelength with a reduced degradation of the RTPL efficiency. My work offers a few ways to obtain a good compromise between the conflicting parameters that govern the efficiency of QWs emitting in the green-yellow spectrum range
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Ehsaan, Muhammad. "Development & exploitation of gene tools for metabolic engineering in saccharolytic Clostridia." Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/30923/.
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C. acetobutylicum A TCC 824 is a well characterized microorganism known for its ability to produce solvents using the Acetone-Butanol-Ethanol (AB E) fermentation process. It can utilize a variety of Cs and C6 sugars, but cannot directly access the complex lignocellulose plant cell wall material which is the most abundant source of carbon in nature. Sophisticated genetic tools are required to enhance the substrate utilisation ability of the organism by incorporating synthetic operons using a synthetic biology approach. Efficient tools were developed for making precise alterations to the C. acetobutylicum genome using either heterologous pyrE or codA genes as counterselection markers. In the case of the former, the utility of the method was also demonstrated in Clostridium difficile. The robustness and reliability of the methods were demonstrated through the creation of in-frame deletions in two genes (spoOA, amylase) using pyrE and also two genes (Cac1502 and Cac2071 (spoOA) using codA. The pyrE system is reliant on the initial creation of a pyre deletion mutant using Allele Coupled Exchange (ACE), that is auxotrophic for uracil and resistant to fluoroorotic acid (FOA). This enables the subsequent modification of target genes by allelic exchange using a heterologous pyre allele from C. sporogenes as a counter-/negative-selection marker in the presence of FOA. Following modification of the target gene, the strain created is rapidly returned to uracil prototrophy using ACE, allowing mutant phenotypes to be characterised in a pyrE proficient background. Crucially, wild-type copies of the inactivated gene may be introduced into the genome using ACE concomitant with correction of the pyrE allele. This allows complementation studies to be undertaken at an appropriate gene dosage, as opposed to the use of multicopy autonomous plasmids. The rapidity of the 'correction' method (5-7 days) makes pyrE strains attractive hosts for mutagenesis studies.
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Liew, Fung Min. "Metabolic engineering of Clostridium autoethanogenum." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/32451/.
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Gas fermentation has emerged as a promising technology that converts waste gases containing CO, CO2 and H2 (also known as syngas) into fuels and chemical commodities. Employed by LanzaTech Inc., Clostridium autoethanogenum is an industrial acetogen that converts gases into ethanol, 2,3-butanediol, acetate, and lactate. Metabolic engineering offers unique opportunities to eliminate side-products, synthesize novel, high-value molecules as diversification strategies, and increase productivities of natural products. However, there had been no scientific reports of genetic manipulation of this acetogen so the overall goal of this PhD project was to develop genetic tools for this gas-utilizing microorganism and construct a hyper-ethanol producing strain via metabolic engineering. The formulation of electroporation and conjugation procedures allowed exogenous DNA to be routinely introduced into the bacterial host. ClosTron mutagenesis and Allele-Coupled Exchange (ACE) techniques were fully exemplified in this bacterium during the construction of knockout, in-frame deletion, and overexpression mutants. Carbon monoxide dehydrogenases (cooS1, cooS2 and acsA) were specifically targeted to elucidate their roles in supporting CO oxidation and carbon fixation. In the ethanol formation pathway, inactivation of bi-functional aldehyde/alcohol dehydrogenases (adhE1 and adhE2) impaired growth on pure CO but elevated ethanol titres. Conversely, inactivation of the more highly expressed aldehyde:ferredoxin oxidoreductase (aor1), but not the weakly expressed aor2, significantly reduced ethanol production, highlighting the importance of aor1 in autotrophic ethanol formation. A double KO mutant of aor1 and aor2 was also generated via ClosTron mutagenesis and pyrE-mediated allelic exchange. In an effort to engineer a robust biocatalyst, the native chaperone systems groESL and/or grpE-dnaK-dnaJ were overexpressed in C. autoethanogenum, resulting in enhanced tolerance towards ethanol, heat and salts. In summary, this study demonstrated the genetic tractability of C. autoethanogenum and revealed gene targets for future metabolic engineering of a hyper-ethanol producing acetogen.
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qqqq and Cehn. "qwe." 碩士, 國立中正大學, 1999. http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22099CCU00045001%22.&searchmode=basic.
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Bchini, Tarek. "Gestion de la Mobilité, de la Qualité de Service et Interconnexion de Réseaux Mobiles de Nouvelle Génération." Thesis, Toulouse, INPT, 2010. http://www.theses.fr/2010INPT0016/document.
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Avec l’évolution rapide des technologies réseaux et télécoms radios mobiles, les chercheurs sont actuellement en train de préparer l’arrivée d’une nouvelle génération baptisée 4G. Le réseau de 4ème génération qui est encore l’objet de travaux de recherche vise à améliorer l’efficacité spectrale et à augmenter la capacité de gestion du nombre des mobiles dans une même cellule. Il tend à offrir des débits élevés en situation de mobilité à grande ou faible vitesse. Il vise aussi à permettre et à faciliter l’interconnexion et l’interopérabilité entre différentes technologies existantes en rendant transparent à l’utilisateur le passage entre les réseaux. Enfin, il vise à éviter l’interruption des services durant le transfert intercellulaire, et à basculer l’utilisation vers le tout IP. Dans ce contexte, nous nous sommes intéressés en premier lieu aux problématiques de la QoS en situation de mobilité au sein d’une technologie candidate à la 4G (WiMAX mobile) pour du trafic temps-réel. Pour cela, nous avons comparé la performance de plusieurs protocoles de mobilité dans le contexte du Handover de niveau 2 et de niveau 3 et plus. Nous avons pour cela fait varier les modèles de mobilité, les configurations et les scénarios. Enfin, nous avons modélisé un algorithme décisionnel qui gère le Handover dans le WiMAX mobile en fonction de plusieurs paramètres d’entrées. Au travers de ces études, nous avons dégagé des protocoles de mobilité qui offrent un niveau de QoS acceptable pour un trafic temps-réel dans le cadre des scénarios envisagés. En deuxième lieu, nous nous sommes concentrés sur les problèmes d’interconnexion et d’interopérabilité entre les réseaux en tenant compte de la mobilité et du Handover vertical entre deux technologies. Pour cela, nous avons proposé de comparer des protocoles de mobilité puis de les combiner afin de diminuer les délais des trafics temps-réel au cours du Handover. Au niveau de l’interconnexion, nous avons proposé des modèles entre WiMAX mobile et de nombreux autres standards (802.11e, UMTS, DVB-S/RCS, LTE). Outre les solutions d’interconnexion, nous avons également mis en évidence la ou les combinaisons de protocoles de gestion de la mobilité qui permettent de garantir de la QoSWith the rapid evolution of mobile radio telecommunications and networks technologies, researchers are currently preparing the arrival of a new generation called 4G. The 4th generation network aims to improve spectral efficiency and increase capacity to manage a large number of mobiles in a cell. It tries to provide high flow rates under high or low mobility. It also aims to enable and facilitate the interconnection and the interoperability between different technologies allowing transparent transition between networks. Finally, it aims to avoid interruption of services during the handover, and to switch an all-IP system. In this context, we are concerned first with QoS and mobility issues in Mobile WiMAX for the real-time traffic. We compared the performance of several mobility protocols in the context of the level 2 and level 3+ handovers. Several mobility models, configurations and scenarios were considered. Finally, we modeled a decision algorithm that manages the handover in mobile WiMAX based on several input parameters.Through these studies, we have identified mobility protocols that provide an acceptable QoS level for real-time traffic under the proposed scenarios. Secondly, we focused on the problems of interconnection and interoperability between networks, taking into account the mobility and vertical handovers between two technologies. For this, we proposed to compare mobility protocols or combine them to reduce delays for real-time traffic during the handover. We also proposed interconnection models between mobile WiMAX and many other standards (802.11e, UMTS, DVB-S/RCS, LTE). Besides interconnection solutions, we also highlighted the combination or combinations of management mobility protocols that can guarantee QoS
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Islam, Mohammad Shahidul, and Syed Nasir Mehdi. "How Different QoS Mechanisms Affect VoIP QoS Metrics." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-15337.
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Voice over Internet Protocol (VoIP) has become a key technology of communication. Our work has been a practical implemenation of different scenarios to show that VoIP voice quality can be improved by adopting certain Quality of Service(QoS) measures such as classification, marking or queuing. It has been discussed that different QoS metrics like delay, packet loss and jitter could affect the voice quality of VoIP. To reduce the negative affects, one option is to implement certain QoS mechanisms with some set of configurations. For this purpose, Cisco IP phones have been configured in our topology with routers, switches, traffic generators, end stations and VoIP quality monitoring software called VQmanager. Tests have been divided into two sets. In one test a fixed bandwidth of 70 kbps is set while in the other test a random bandwidth is set with trafic generators unleashing packets of traffic. In both these tests further scenarios with configurations are worked out. They include no QoS, Auto Qos and Customized Qos mechanisms. Results have been indicative of top performance by the Customized QoS mechanism, in both sets of tests, followed by Auto QoS and no QoS mechanisms. It has been observed that a customized scenario could be a particular configuration to any organization’s needs and that will have the lowest delay, jitter and packet loss which are the main QoS metrics that impact the voice quality of VoIP. It can be fundamentally composed of classification of voice, data or web-traffic, marking and queuing depending upon the need of the organization. It is finally suggested to carry more tests in companies to get more data for analysis
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Cushnie, John. "QoS charging for Internet access networks : the wireless QoS gateway." Thesis, Lancaster University, 2003. http://eprints.lancs.ac.uk/12300/.
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WANG, XIAODONG. "QoS ISSUES AND QoS CONSTRAINED DESIGN OF WIRELESS SENSOR NETWORKS." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1144634884.
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Jonsson, Björn. "Bluetooth QoS Scheduler." Thesis, KTH, Mikroelektronik och Informationsteknik, IMIT, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-93114.
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Bluetooth is a low cost, short-range radio technology that enables electronic devices to communicate wirelessly via ad-hoc networks. Different kinds of applications may run over these networks, some of these applications with particular Quality of Service (QoS) requirements. One such application could for instance be an Audio application which need data frames to be delivered at regular interval to work properly. The communication over Bluetooth links is totally controlled by one of the participating nodes. Since this node controls the traffic and thereby controls the QoS within the network its communicating behaviour is of great importance for maintaining QoS reservations. A central part in maintaining QoS reservations is the scheduler, which prioritises between different tasks to be done such as which device that is allowed to transmit next. There is no standardised way to implement the Bluetooth scheduler. However, a Bluetooth scheduler should be able to handle QoS reservations, maintain fairness among the participating nodes, and utilise the available bandwidth efficiently. Furthermore a key requirement in Bluetooth is simplicity, therefore a Bluetooth scheduling algorithm should be of low complexity. This master thesis presents a new patented solution for an intra-piconet scheduling algorithm that is capable of maintaining QoS reservation, while being fair and also meet the low complexity requirement. This algorithm is presented in detail in the thesis and has been implemented in an ns2- based Bluetooth simulator. Simulations in this simulator are presented that verifies the scheduling algorithms functionality.Bluetooth är en standard för trådlös ad-hoc kommunikation. Denna standard definierar i antalet noder begränsade nätverk (piconet) som kan kopplas samman till större nätverk (scatternet). Många olika typer av applikationer kan tänkas använda dessa nätverk, vissa av dessa med speciella krav på Quality of Service (QoS). Ett exempel så en dylik applikation är ljudöverföringar som kräver att data överförs med jämna mellanrum för att kunna fungera tillfredställande. Kommunikationen över ett Bluetooth-piconet kontrolleras helt av en av de deltagande enheterna. Eftersom denna enhet kontrollerar trafiken kontrollerar den också upprätthållandet av QoS reservationerna. En central del i detta upprätthållande är schemaläggaren, som är den del i en Bluetoothenhet som prioriterar mellan olika saker som ska utföras. Ett exempel på en sådan prioritering kan vara vilken enhet i nätverket som ska få kommunicera härnäst. Bluetooth standarden beskriver inte hur denna schemaläggare ska implementeras. Grundläggande krav på en Bluetooth schemaläggare är att den ska kunna hantera och upprätthålla QoS reservationer samtidigt som den delar den befintliga kapaciteten på ett rättvist och effektivt sätt mellan de deltagande enheterna. Vidare bör den ha en låg komplexitet eftersom enkelhet är ett krav på alla delar i ett Bluetoothsystem. Detta examensarbete presenterar en ny patenterad algoritm för schemaläggning i begränsade Bluetoothnät som är kapabel att upprätthålla QoS-reservationer, samtidigt som den distribuerar den tillgängliga kapaciteten på ett rättvist sätt. Algoritmen möter också upp till kravet på låg komplexitet. Rapporten innehåller vidare simuleringar av algoritmens funktion, dessa har utförts i en ns2-baserad Bluetooth miljö och verifierar algoritmens funktionalitet.
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Lahdenperä, J. (Juho). "QoS 4G-verkoissa." Bachelor's thesis, University of Oulu, 2017. http://urn.fi/URN:NBN:fi:oulu-201711153110.
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Tutkielma on kirjallisuuskatsaus, jossa perehdytään nykyään käytettäviin Quality of Service (QoS) ratkaisuihin 4G-verkoissa. QoS on tärkeä niin käyttäjän, kuin palvelun tarjoajan näkökulmasta. QoS:n avulla varmistetaan kullekin verkon käyttäjälle riittävä palvelun taso. QoS:n tarkastelua tarvitaan myös erilaisten järjestelmien suunnittelussa, että ymmärretään mitä järjestelmältä vaaditaan. 4G-verkon QoS parametrit on standardisoitu ja laitteiden QoS-mekanismit ovat globaaleilla televiestintämarkkinoilla tärkeä kilpailutekijäThis thesis is a literature review, that orients to the concept of modern day Quality of Service solutions in 4G-networks. QoS is important from the users’ as well as the service provider’s point of view. QoS provides a level of service for each network user and it is also required in system design to know what is required from the system. QoS parameters of 4G network are standardized and the QoS mechanisms are an important competitive factor in the global telecommunications market
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Kopecký, Lukáš. "QMS průmyslového podniku." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254327.
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The subject of this master´s thesis is the improvement of a quality management system in selected industrial company using the DMAIC methodology. For this purpose, current status of quality management system was analysed and compared with requirements of the ČSN EN ISO 9001 standard. Based on determined shortcomings, corrective measures were proposed. The measures related to process management and risk analysis were performed within the pactical part of this thesis.
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Boughanmi, Najet. "Conception conjointe des systèmes contrôlés en réseaux sans fil." Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL021N/document.
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Le cadre de cette thèse est l'étude des systèmes contrôlés en réseau sans fil (SCRSF) qui utilise la technologie IEEE 802.15.4. Le premier objectif est d'étudier la pertinence de l'utilisation du réseau de type IEEE 802.15.4 pour les SCRSF puis de proposer et d'évaluer des mécanismes pour garantir la Qualité de Service (QdS) offerte par le réseau au système contrôlé. Nous analysons l'utilisation des slots temporels réservés (GTS) dans le cadre des SCRSF et les contraintes qui en découlent. De plus, nous proposons des mécanismes de gestion de la QdS avec priorité aussi bien pour le mode avec balise que pour le mode sans balise du protocole IEEE 802.15.4. Ces propositions ont été validées par des simulations et une partie de manière analytique. Notre deuxième objectif est de concevoir, d'une manière conjointe, les SCRSF pour pouvoir régler en ligne la QdS offerte par le réseau en fonction de la Qualité de Contrôle (QdC) du système contrôlé. Nous proposons des protocoles d'adaptation en ligne de la QdS du réseau qui prennent en compte la QdC du système contrôlé. Ces protocoles ont été validés par simulations et une implémentation réelle de chacun d'eux est proposéeIn this thesis, we study wireless networked control systems (WNCS) which use the IEEE 802.15.4 technology. The first objective is to study the pertinence of the use of the IEEE 802.15.4 for the WNCS, then to propose and evaluate QoS management mechanisms which guarantee the Quality of Service (QoS) offered by network to the controlled system. We analyse the use of the guaranteed temporel slots (GTS) for WNCS and in which conditions it is possible. We propose QoS management mechanisms with priority for both the beacon enabled mode and the non-beacon enabled mode of the IEEE 802.15.4 protocol. These proposals are validated through simulations and partially with analytical approach. The second objective is to design the WNCS so that the QoS offered by the network is adated online depending on the Quality of Control (QoC) on the controlled system. We propose QoS online adaptation protocols which take as parameter the QoC of the system. These protocols are validated through simulations and a realistic implementation of them is proposed
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Tian, Min [Verfasser]. "QoS integration in Web services with the WS-QoS framework / Min Tian." Berlin : Freie Universität Berlin, 2005. http://d-nb.info/1021667587/34.
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Tamura, Gabriel. "QoS-CARE : a reliable system for preserving QoS contracts through dynamic reconfiguration." Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10031/document.
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Le principal défi de cette thèse est de préserver de façon fiable la qualité de service (QoS) définie par contrats dans des systèmes logiciels à base de composants, ceci dans des conditions changeantes d'exécution du système. En réponse à ce défi, nous présentons deux contributions. La première est un modèle pour les applications logicielles à base de composants avec contrats de qualité de service et règles de reconfiguration définies par des graphes attribués typés. Ainsi, nous utilisons des modèles formels à l'exécution pour reconfigurer de manière fiable des applications logicielles de façon à préserver les contrats de QoS. Plus précisément, nous montrons la faisabilité d'exploiter des patrons de conception à l'exécution dans des boucles de reconfiguration tout en garantissant les niveaux de QoS attendues. Nous mettons en œuvre ce modèle formel par le biais d'une architecture à base de composants qui peut être utilisée comme une couche supplémentaire de la plateforme SCA, ceci afin de préserver les contrats de QoS.La seconde contribution est la caractérisation des propriétés d'adaptation pour évaluer les systèmes logiciels auto-adaptatifs de manière standardisée et comparable. De par leur nature, les mécanismes d'adaptation des systèmes logiciels auto-adaptatifs sont essentiellement des boucles de rétroaction telles que définies par la théorie du contrôle. Ainsi, pour les évaluer, il est nécessaire de ré-interpréter ces proprétés dans le domaine du logiciel. Nous définissons la fiabilité de la réalisation de notre modèle formel en termes de sous-ensemble des propriétés d'adaptation caractérisées, et nous montrons que ces propriétés sont garanties dans cette réalisationThe main challenge of this Thesis is to reliably preserve quality of service (QoS) contracts in component-based software systems under changing conditions of system execution. In response to this challenge, the presented contribution is twofold. The first is a model for component-based software applications, QoS contracts and reconfiguration rules as typed attributed graphs, and the definition of QoS-contracts semantics as state machines in which transitions are performed as software reconfigurations. Thus, we effectively use (formal) models at runtime to reliably reconfigure software applications for preserving its QoS contracts. More specifically, we show the feasibility of exploiting design patterns at runtime in reconfiguration loops to fulfill expected QoS levels associated to specific context conditions. We realize this formal model through a component-based architecture and implementation that can be used as an additional layer of SCA middleware stacks to preserve the QoS contracts of executed applications.The second contribution is the characterization of adaptation properties to evaluate self-adaptive software systems in a standardized and comparable way. By its own nature, the adaptation mechanisms of self-adaptive software systems are essentially feedback loops as defined in control theory. Thus, it results reasonable to evaluate them using the standard properties used to evaluate feedback loops, re-interpreting these properties for the software domain. We define the relibility of our formal model realization in terms of a subset of the characterized adaptation properties, and we show that these properties are guaranteed in this realization
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Fujikawa, Kenji. "A Study on QoS Guarantee, QoS Routing and Multicast on the Internet." 京都大学 (Kyoto University), 2000. http://hdl.handle.net/2433/151472.
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Horbach, Jan. "Dynamische Bandbreitenbeschränkung mit QoS." Master's thesis, Universitätsbibliothek Chemnitz, 2001. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200101001.
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Diese Diplomarbeit beschäftigt sich mit der
"schleichenden Abschaltung" begrenzter
Netzzugänge bei Überschreitung eines vorgegebenen
Datenvolumens und der Anwendung dieser Technologie
im Chemnitzer Studentennetz. Nutzer, die bestimmte
Transfervolumina überschreiten, werden
schrittweise einer immer schlechter bewerteten
Verkehrsklasse zugeordnet, wo ihnen weniger
Bandbreite zur Verfügung steht. Dazu werden die
Möglichkeiten, die der Linux-Kern hinsichtlich
Quality of Service bietet, genutzt.
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Mbenza, Alexandre Seth da Silva. "Quality Manager System (QMS)." Master's thesis, Instituto Politécnico de Setúbal. Escola Superior de Tecnologia de Setúbal, 2019. http://hdl.handle.net/10400.26/31330.
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Relatório de projeto do Mestrado em
Informática de GestãoA evolução tecnológica a nível da indústria e de metodologias utilizadas torna imperativo que as organizações adotem novos mecanismos e que estas novas tecnologias reflitam uma maior eficiência para as mesmas. Neste contexto, as organizações apostam cada vez mais na gestão da qualidade, encarando-o como uma ferramenta eficaz para fazer face à competitividade nacional e internacional. Não menosprezam toda a atividade relacionada com a inovação, mas consideram que é fundamental uma base com qualidade, permitindo assim atingir patamares superiores. O presente relatório visa abordar a metodologia e o processo de implementação das normas internacionais a nível geral. O conhecimento adquirido ao longo do percurso profissional no desenvolvimento de um software, bem como em outras competências intrínsecas, permitiram idealizar o desenvolvimento de uma plataforma capaz de gerir e implementar um sistema de gestão de qualidade. com o intuito de que este seja capaz de evoluir e de ser mantido de forma organizada. Com a implementação da ISO 27001, neste contexto, e após a análise de soluções existentes no mercado e da estrutura de implementação e certificação das normas internacionais, surgiu a necessidade de apresentar uma solução que vise facilitar este mesmo processo e que também ajude na manutenção de um sistema de gestão. Para este desenvolvimento foi necessário efetuar um levantamento de alguns sistemas que já existiam nesta área, sendo que as soluções encontradas no mercado não satisfaziam a necessidade de um sistema de gestão de qualidade. Apesar destas permitirem gerir este tipo de sistemas de qualidade, não estão focadas no processo de implementação e certificação das ISO. Deste modo, o QMS4.0 tem como objetivo minimizar esta lacuna identificada e facilitar o processo interno das empresas.
Technological developments in industry and in the methodologies used make it imperative for organizations to adopt new mechanisms and new technologies and to reflect on greater efficiency. In this context, organizations are increasingly focusing on quality management, seeing it as an effective tool to address national and international competitiveness. They do not underestimate all innovation-related activity, but considering that, a quality base is fundamental, thus allowing to reach higher levels. This report aims to address the methodology and process of implementation of international standards at the general level. The knowledge acquired along the professional career in software development as well as in other intrinsic skills allowed us to idealize the development of a platform capable of managing and implementing a quality management system in order to be able to evolve and to develop. be kept in an organized manner. With the implementation of ISO 27001 in this context, and after the analysis of existing solutions in the market and the structure of implementation and certification of international standards emerged the need to present a solution that aims to facilitate this same process and that also helps in maintaining a system management. For this development, it was necessary to make a survey of some systems that already existed in this area, and the solutions found in the market did not satisfy the need for a quality management system. Although these allow the management of such quality systems, they aren’t focused on the ISO implementation and certification process. This QMS4.0 aims to minimize this identified gap and facilitate this internal process of companies.
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Roumani, Ali Mohamad. "QoS-based multicast routing." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0034/MQ52943.pdf.
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Grift, Werner. "Visualizing Qos in networks." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/17356.
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Thesis (MSc)--University of Stellenbosch, 2006.ENGLISH ABSTRACT: Network simulations generate large volumes of data. This thesis presents an animated visualization system that utilizes the latest affordable Computer Graphics (CG) hardware to simplify the task of visualizing and analyzing these large volumes of data. The use of modern CG hardware allows us to create an interactive system which allows the user to interact with the data sets and extract the relevant data in real time. We also present an alternate approach to the network layout problem, using Self Organizing Maps to find an aesthetic layout for a network which is fundamental to a successful network visualization. We finally discuss the design and implementation of such an network visualization tool.
AFRIKAANSE OPSOMMING: Netwerk simulasies genereer groot volumes data. Hierdie tesis stel voor ’n geanimeerde visualiseringwat gebruik maak van die nuutste bekostigbare rekenaar grafika hardeware om die visualisering van groot volumes data te vergemaklik. Die gebruik van moderne rekenaar grafika hardeware stel ons in staat om sagteware te skep wat n gebruiker in staat stel om met die data te werk. Ons stel voor ’n alternatiewe benadering om die netwerk se uitleg daar te stel, met die hulp van tegnieke wat gebruik word in die studie van neurale netwerke. Ons bespreek dan die ontwerp en implementering van so ’n netwerk visualisering program.
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Horbach, Jan. "Dynamische Bandbreitenbeschränkung mit QoS." [S.l. : s.n.], 2001. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10047781.
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Farber, Dawn L. (Dawn Lee). "Multi-channel QRS detector." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10868.
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Tondello, Gustavo Fortes. "Especificação semântica de QoS." Florianópolis, SC, 2008. http://repositorio.ufsc.br/xmlui/handle/123456789/91511.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da ComputaçãoMade available in DSpace on 2012-10-23T23:47:03Z (GMT). No. of bitstreams: 1 259451.pdf: 1464324 bytes, checksum: f73443a4cdf02c0e6aa0420528c89c98 (MD5)
Este trabalho apresenta a ontologia QoS-MO que permite a especificação de características e requisitos de QoS para Web Services Semânticos ou Componentes de Software e pode ser facilmente utilizada para estender a OWL-S ou outras ontologias de descrição funcional de Componentes. As especificações de QoS modeladas a partir da ontologia QoS-MO podem ser utilizadas no projeto, desenvolvimento, publicação e descoberta de Web Services ou Componentes de Software. Um mecanismo de busca semântica de Web Services ou Componentes de Software foi especificado, voltado para a descoberta de Componentes que atendam a um conjunto definido de restrições de QoS, utilizando a ontologia QoS-MO e a linguagem de consulta SPARQL. Um protótipo deste mecanismo foi desenvolvido, contando tanto com uma interface de programação como uma interface Web. Os testes realizados demonstraram que o mecanismo proposto é viável e apresenta um desempenho aceitável e que a ontologia definida é capaz de expressar características de QoS complexas. A comparação com mecanismos de descoberta de Web Services de propostas similares demonstrou que a abordagem QoS-MO é mais simples e eficiente, pois não depende de nenhum algoritmo complexo para sua execução, apenas de um mecanismo de inferência simples e da linguagem SPARQL.
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Bumbál, Miroslav. "QoS v IP síti." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-217998.
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Master 's thesis deals about computer networks, which constitutes a global communication structure and play a very important role in today's society. The rapid development of Internet, the emergence of new multimedia applications and their increasing use of calls to the efficient functioning of the creation of such governance mechanisms of transmission, which are able to secure the required parameters. The thesis deals about the issue of quality of service (QoS) in IP networks. It presents the basic characteristics and requirements of these networks for the transmission of sensitive data by the quality of services, deals with the QoS definition, and describes the essential parameters to be followed to achieve the required quality of service in practical deployment. In addition, lists the various principles and options to ensure QoS in computer networks. Generally, it represents the Cisco 1841 router features and options to ensure quality of service in the network based on these routers. Practical thesis part provides two types of model IP networks, which were designed in order to verify the impact of service quality in real practice. Of the known methods to ensure QoS, which include a mechanism of Integrated services, Differentiated services, it focus its content about the Differentiated Services and the implementation of these in proposed network model. The last part of the work presents the results obtained by the impact of quality of service for the applications and their assessment.
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Kavan, Radovan. "QoS v systému UMTS." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218026.
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This thesis treats of QoS (Quality of Service) in UMTS system. The term quality of service is frequently used, recently, however not only in computer networks, but also more and more in mobile networks also. Present system of 2nd generation (2G) GSM enables only limited exploitation of QoS function. System UMTS is a system of 3rd generation (3G) already and contains quality of service in greater measure which is ensured with number of algorithms and functions. Individual QoS functions enable effective utilization of radio interface, support maintenance of planned coverage and offer high spectral efficiency. Functions that cater to quality of service are called RRM functions (Radio Resource Management). There exist five basic functions in UMTS system that are Admission control (AC), Power control (PC), Load control (LC), Handover control (HC) and Packet scheduler (PS). These functions are responsible for control of network access, control of power, control of network load, control of handover and packet (bit rate) scheduling. Last three functions are usually collectively designated as Congestion control, control of network overload. UMTS layer model, differentiation of services, traffic classes and 3GPP concept are also discussed. In thesis the attention is piad to Admission control algorithm – control of network access – in the uplink direction and to different ways of load (in the cell) modeling. Individual approaches are simulated in MATLAB. A possibility of using algorithm in the real system is discussed in conclusion.
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Kalina, Tomáš. "QoS v síti VŠE." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-164040.
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The diploma thesis is focused on analysis and deployment of Quality of Services (QoS) in a computer network of The University of Economics in Prague (VŠE). The thesis describes the main QoS technologies focusing on technology Diffserv and its deployment with using available network devices in computer network of VŠE. In thesis the needs of network services and protocols for quality of services with division into different classes of services according to priority are discussed. The thesis explains the benefits and drawbacks of deploying QoS in the environment of VŠE with regard to wired and wireless network. In the practical part recommendations are applied to the production network and subsequently the benefits of modification are evaluated.
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Souihi, Sami. "Mise en oeuvre d’une plateforme de gestion et de dissémination des connaissances pour des réseaux autonomiques." Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1193/document.
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La croissance du réseau Internet, l'émergence de nouveaux besoins par l'avènement des terminaux dits intelligents (smartphones, tablettes tactiles, etc.) et l'apparition de nouvelles applications sous-jacentes induisent de nombreuses mutations dans l'usage de plus en plus massif des technologies de l'information dans notre vie quotidienne et dans tous les secteurs d'activités. Ces nouveaux usages ont nécessité de repenser le fondement même de l'architecture réseau qui a eu pour conséquence l'émergence de nouveaux concepts basés sur une vue "centrée sur l'usage" en lieu et place d'une vue "centrée sur le réseau". De fait, les mécanismes de contrôle du réseau de transport doivent non seulement exploiter les informations relatives aux plans de données, de contrôle et de gestion, mais aussi les connaissances, acquises ou apprises par inférence déductive ou inductive, sur l'état courant du réseau (trafic, ressources, rendu de l'application, etc.) de manière à accélérer la prise de décision par les éléments de contrôle du réseau. Les travaux faits dans le cadre de cette thèse concernent ce dernier aspect et rejoignent plus généralement ceux tournés sur les réseaux autonomiques. Il s'agit dans cette thèse de mettre en oeuvre des méthodes relatives à la gestion, à la distribution et à l'exploitation des connaissances nécessaires au bon fonctionnement du réseau de transport. Le plan de connaissances mis en oeuvre ici se base à la fois sur l'idée de développer une gestion au sein d'une structure hiérarchisée et adaptative où seuls certains noeuds sélectionnés sont en charge de la dissémination des connaissances et l'idée de relier ces noeuds au travers d'un ensemble de réseaux couvrants spécialisés permettant de faciliter l'exploitation de ces connaissances. Comparée aux plateformes traditionnellement utilisées, celle développée dans le cadre de cette thèse montre clairement l'intérêt des algorithmes élaborés au regard des temps d'accès, de distribution et de partage de charge entre les noeuds de contrôle pour la gestion des connaissances. A des fins de validation, cette plateforme a été utilisée dans deux exemples d'application: le Cloud computing et les smartgridsThe growth of the Internet, the emergence of new needs expressed by the advent of smart devices ( smartphones, touchpads , etc. ) and the development of new underlying applications induce many changes in the use of information technology in our everyday life and in all sectors. This new use that match new needs required to rethink the foundation of the network architecture itself, which has resulted in the emergence of new concepts based on a "use-centeric" view instead of a "network-centric" view. In fact, the control mechanisms of the transmission network must not only exploit the information on data, control and management planes, but also the knowledge acquired or learned by inductive or deductive inference on the current state of the network (traffic, resources, the rendering of the application, etc.) to accelerate decision making by the control elements of the network. This thesis is dealing with this latter aspect, which makes it consistent with work done on autonomic networks. It is about conceiving and implementing methods for the management, distribution and exploitation of knowledge necessary for the proper functioning of the transmission network. The knowledge plane that we implemented is based on both the idea of developing a management within an adaptive hierarchical structure where only some selected nodes are responsible for the dissemination of knowledge and the idea of linking these nodes through a spanning set of specialized networks to facilitate the exploitation of this knowledge. Compared to traditionally used platforms, the one developed in this thesis clearly shows the interest of the developed algorithms in terms of access time, distribution and load sharing between the control nodes for knowledge management. For validation purposes, our platform was tested on two application examples : Cloud computing and smart grids
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Smit, Nellie Jacoba. "A qualitative study of selected micro-organisms in geophagic soil from Qwa-Qwa." Thesis, Bloemfontein : Central University of Technology, Free State, 2011. http://hdl.handle.net/11462/165.
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Thesis (M. Tech.(Biomedical Technology)) - Central University of technology, Free State, 2011The existence of geophagia from as early as 460 BC up to now, makes it relevant to investigate all aspects related to geophagia. Geophagia is a direct route for potential transmission of pathogens to the human host, through the ingestion of soil. Soil-borne diseases in humans are causing growing concern as sewage disposal, which involve sewage sludge and waste water drainage from these plants, is on the increase. It is estimated that approximately seven million tons of sewage sludge is produced annually and that 54% of this sewage sludge is introduced into soil. Data on enteric infection in humans caused by contamination from soil is limited and need further investigation. The aim of the study was, therefore, to collect information on the microbiological presence in geophagic soil in the Qwa-Qwa district. Objectives included the collecting of information regarding various sampling sites in the Qwa-Qwa district and also soil samples sold by vendors, investigation of the prevalence of known human pathogenic bacteria and fungi in geophagic soil, investigating the culturability of Salmonella enteritidis in geophagic soil in comparison with the viability of these organisms in soil for long periods of time, investigating potential antimicrobial activity of geophagic soil, as some of the geophagists are convinced that the geophagic soils have medicinal properties, and to determine the microbial diversity of geophagic soils, which can not be accomplished by conventional microbial culturing methods.
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Zedníček, Vlastimil. "Detekce QRS založená na vlnkové transformaci." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220878.
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This thesis deals with implementation of detector QRS complex with use of wavelet transform. The first part is focused on formation and possibility to measure cardiac activity. The other part of thesis we will familiarise with the different possibilities of detection QRS complex and we intimately focus on wavelet transform that will be used for a project of detection QRS complex. The practical part of thesis focuses on the project of detector in programming language Matlab and his different setting. This projected detector has been tested with CSE database. Achieved results of projected detector are evaluated with the results of others authors.
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Bakhsh, Helen Jameel H. "ATL-QoS : an adaptive trust-aware location-based framework for achieving QoS in MANETs." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/atlqos-an-adaptive-trustaware-locationbased-framework-for-achieving-qos-in-manets(d0c5f89e-5576-4a91-a601-aa4aca60e15a).html.
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Mobile ad hoc networks (MANETs) have gained increasing attention from industry for their potential applications. MANETs allow devices to communicate in areas with no pre-existing communication infrastructure. In MANETs, node mobility leads to dynamic changes in network topologies and fluctuations in network available bandwidth. The lack of infrastructural support means that communication nodes need to collaborate among themselves functioning as routers (intermediate nodes) for other nodes. This places additional processing and communication loads onto the communication nodes and opens up doors to more active attacks by intermediate nodes. It is also worth noting that mobile nodes are typically battery powered, and they are more restrictive in terms of storage space and processing capabilities than their wired counterpart. These MANET features indicate that achieving QoS in MANETs should be done in the most cost-effective manner. In this thesis, a novel Adaptive Trust-aware Location-based (ATL-QoS) framework is proposed. The ATL-QoS framework can harvest fluctuating available bandwidth in the underlying network to deliver high priority traffic in various network conditions. The novelty of the framework lies in that it uses single path and multiple path deliveries and packet duplication over multiple path, in an adaptive manner, in an attempt to increase high priority traffic delivery with minimum bandwidth overhead costs. The framework handles low and high priority traffic in a differential manner. To implement these ideas, two novel ATL-QoS components are designed: (1) a Trust-Aware Dynamic Location-based (improved version) (TADLV2) multiple path discovery protocol and (2) a path Selection, traffic Allocation, and path Verification (SAV) solution. The TADLV2 protocol is designed to discover multiple path between a pair of communication nodes with minimum bandwidth overheads, we first designed TADL protocol and then an improved version of TADL, TADLV2. The SAV solution is designed to increase high priority traffic delivery success. These ATL-QoS framework ideas are implemented and evaluated using the NS-2 simulation and compared against the most relevant protocol in the literature. The simulation study shows that ATL-QoS outperforms the relevant protocol in terms of reducing routing overheads and increasing packet delivery ratios. These enhancements making ATL-QoS more effective in providing QoS.
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Porwal, Rupesh. "Adaptive Selective Flooding Qos Routing." Thesis, Indian Institute of Science, 2002. http://hdl.handle.net/2005/51.
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The routing strategy used in today's Internet is best-effort service, where all data packets are treated equally. This type of service is not suited for applications such as video conferencing, and video on demand, that requires the availability of certain resources (such as bandwidth) to be guaranteed for them to function properly. The routing in this context, called Quality-of-Service (QoS) Routing, is the problem of finding suitable paths that meet the application's resource requirements.
The majority of proposed QoS routing schemes operate by maintaining the global state of the network, and using this knowledge to compute the QoS route. However, all these schemes suffer from the inherent drawback of scalability, because of the need for each node to collect state information about the complete network. The other type of QoS routing schemes do not maintain network state information, but instead flood the network with QoS connection establishment requests. This type of scheme suffers from excessive message overhead during QoS connection establishment.
In this thesis, we present a new QoS routing algorithm that is a combination of the above-mentioned two schemes (i.e., global state and flooding based). The algorithm aims at minimizing the message overhead associated with these two schemes and still maintaining the positive aspects of both of them. The basic idea of the algorithm is: to reach to a destination, the path(s) will always pass through a specific set of intermediate nodes. The algorithm discovers such intermediate nodes (limited by a hop count threshold value needed to reach there). When a QoS connection request arrives at a node, it selects the feasible path leading to the intermediate node for the requested destination. The QoS connection establishment message (or routing message) is forwarded along this path. When the message arrives at the intermediate node, the further path is decided through same logic. To decide the path that leads to the intermediate node, the algorithm maintains the link state related to these intermediate nodes, and link state updates are restricted only with regard to these intermediate nodes. Because of this restriction in link state updation, one has less message overhead, compared to the global state based routing scheme. Further, the algorithm tries to group these intermediate nodes in such a way that the routing message need be sent to only one of the grouped intermediate nodes, and still makes sure that all the possible paths are covered. Therefore, one has a reduced message overhead because of grouping.
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Hao, Fang. "Scalability techniques in QoS networks." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/9175.
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Korkmaz, Turgay. "QoS routing in packet networks." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/289740.
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The current best-effort service of the Internet is not sufficient to meet the demands of emerging real-time network applications (e.g., video conferencing, Internet telephony). This has motivated the development of new networking technologies (e.g., Intserv, Diffserv, MPLS) that are geared towards providing quality-of-service (QoS) guarantees (e.g., bandwidth, delay, fitter, reliability) to prospective flows. Various aspects of these technologies are being extensively investigated in the research community. In this dissertation, we focus on the routing aspect, with the objective of providing scalable and computationally efficient solutions. The QoS routing problem involves two tasks: (a) capturing and disseminating the state information of the underlying network; and (b) using this information to compute resource-efficient constrained paths. In the presence of multiple constraints (QoS link parameters), these two tasks become notoriously challenging. We investigate several key issues in QoS routing and discuss how to integrate the provided solutions into evolving state-dependent and hierarchical routing protocols (e.g., PNNI and QoS-extended OSPF). First, we develop a hybrid mechanism based on both flooding and tree-based broadcasting for reliable and efficient dissemination of dynamic link-state parameters, such as bandwidth. Second, we present a scalable, source oriented state aggregation methodology for hierarchical networks. Third, we introduce several heuristics and approximation algorithms for path selection under multiple QoS constraints. Fourth, we consider the path selection problem under inaccurate (probabilistically modeled) state information, and provide a heuristic for a special yet important case of this problem, namely, routing under bandwidth and delay constraints. Finally, we evaluate the performance of the proposed methods through simulations.
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Walsh, S. M. "Packet scheduling for wireless QOS." Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487465.
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Since their arrival in the late 90's wireless packet schedulers have sought to seamlessly re-apply the concepts of fair queuing (FQ) algorithms (traditionally employed in wire-mediated communications) to provide fairness, throughput and delay gutUlUltees to individual sessions in the wireless environment. What has militated against a smooth transition in this regard is the presence of unpredictable bursty location-dependent channel errors due to fading on the wireless channel. The approach generally employed by wireless schedulers for minimizing the effects of channel errors is to use a compensation policy. Compensation has traditionally been applied in two -ways: (a) penalizing sessions that have utilized extra bandwidth gained from the loss ofanother session and (b) reserving a fraction ofthe system bandwidth. This dissertation presents a novel scheduling approach that employs multiple sources of compensation so that an emphasis is placed on allowing sessions to recover as quickly as possible from channel errors, while at the same time preserving the guarantees ofother sessions in the system. Two crucial factors are identified that influence how wireless packet scheduling should be performed namely the channel bandwidth and the traffic variation. In order to better understand the dynamics ofthese two driving forces, this dissertation quantifies and analyzes the behavior of each ofthese parameters in typical real-world worst-case scenarios. Through investigating the nature ofthese two aspects ofthe network, a number of conclusions are drawn on how certain wireless scheduling procedures should be implemented. In particular the recording of lost service and the application of compensation are significantly affected by the nature of these two system attributes. It is shown that wireless scheduling algorithms must incorporate far more system knowledge than what was traditionally required for the wired environment. This research proposes a novel traffic profile and priority based wireless fair queuing (TPP-WFQ) scheduling algorithm that is heavily reliant on system functions that perform; bandwidth management, weight adjustment, link adaptation, queue management, traffic classification and traffic monitoring. Several novel attributes are introduced with the TPP-WFQ algorithm, these include: (i) A novel lag/lead calculation model that makes use of knowledge of the traffic profile to accurately measure the amount of service lost and gained for different sessions when an error occurs. (ii) A novel compensation approach that adopts five sources ofcompensation. This allows for a fast recovery time which is the fundamental attribute that has motivated extensive research in the field of wireless scheduling. (iii) A classbased weight adjustment function that manages the weights for all sessions in the system when partial errors occur on channels due to link adaptation. (iv) A priority-based compensation approach that ensures that compensatory resources are prioritized according to the class oftraffic being compensated. This ensures that delay-sensitive sessions recover more quickly than delay-tolerant ones. Detailed simulations incorporating multiple worst-case scenarios illustrate that these areas of novelty enable TPP-WFQ to perform significantly better than selected high ranking schedulers presented in the literature at providing strong QoS to sessions in an error prone environment. In particular, we demonstrate that TPP-WFQ allows delay-sensitive real-time sessions to becom~ more resilient to poor channel conditions.
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Martins, José Carlos Ferreira da Silva. "QoS em servidores HTTP Apache." Master's thesis, Universidade de Évora, 2015. http://hdl.handle.net/10174/17549.
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Os serviços baseados na Internet têm registado um crescimento contínuo e acelerado nos
últimos anos, dependendo o seu sucesso, em larga medida, da qualidade de serviço prestada.
A sociedade moderna tornou-se fortemente dependente da Internet e dos vários serviços nela
disponibilizados.
Nesta dissertação é abordado o problema da qualidade de serviço em servidores HTTP, com
particular ênfase no servidor HTTP Apache. Neste trabalho, é definido e implementado
um sistema original de controlo em cadeia fechada de QoS, baseado nas metodologias da
teoria de controlo, demonstrando-se a sua robustez, estabilidade e capacidade para gerir
os recursos de forma dinâmica. Por fim, é comprovada a capacidade do sistema realizar a
diferenciação de serviço (DiffServ) entre duas classes de sítios: Premium e Outros. Esta
qualidade é comprovada para os objetivos erro nulo, rejeição de perturbações e seguimento
de referência; Abstract:
QoS for Apache HTTP server
Internet-based services have registered a continuous and rapid growth in recent years, depending
their success to a large extent on the provided quality of service. Modern society
has become heavily dependent on the Internet and the various services it provides.
This thesis addresses the issue of quality of service in HTTP servers, with particular emphasis
on the Apache HTTP server. In this work, a closed-loop system with QoS, based on
control theory methodologies, is defined and implemented. The proposed system robustness,
stability and ability to manage resources dynamically is shown. Finally, it is confirmed
the system’s ability to provide differentiated services (DiffServ) between two classes of sites:
Premium and Others. This quality is proven to the objectives regulatory control, disturbance
rejection and time-varying reference.
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Adámek, David. "Implementace QoS v přístupové síti." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217611.
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This diploma thesis deals with computer networks which play a key role in present society. More and more demands are placed on these networks (especially on quality of services and throughput) because of fast-growing developement of services such as voice and video real-time transmissions. All the packets in typical Ethernet networks are equal. Therefore it is sometimes impossible for the application to maintain required throughput speed of a network. For this case it is useful to take some mechanisms into the consideration. These mechanisms (sometimes called QoS) are able to distinguish different types of transmissions and traffic, analyze them and then prioritize them according to some pre-defined set of rules. The most famous mechanisms are Integrated Services and Differentiated Services. The implementation of Differentiated Services is the goal of this thesis.
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Fabricius, Marián. "Zajištění QoS v UMTS síti." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218065.
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Diploma thesis deals with assign and distribution quality of service in mobile UMTS telecommunication networks. The project consists of two parts, theoretical and practical. Theoretical part of the project is focused to familiarize with functionality of the UMTS network with the main aspect at admission mechanism in radio part of the network as well as quality of service assign mechanisms according to service demands within core network of UMTS. Practical part of the project is given to simulation program OPNET Modeler and its capabilities in network design and testing various parameters of UMTS network with implementation quality of service mechanism. As the asset of diploma thesis becomes designed functional prototype of UMTS network with various options for individual settings user equipment as well as fixed mobile networks nodes.
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Kolmačka, Jan. "Zajištění QoS v bezdrátových sítích." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218563.
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The diploma thesis gives the overall information about the field of wireless networks of standards 802.11 and Quality of Service (QoS). The practical measurements describe the reactions of multimedia dataflows in the networks 802.11a/b/g/n. The individual standards, offered services, access methods and the network architecture are analyzed in the theoretical part. In the following part there is written about QoS and its basic parameters. Moreover, the standard 802.11e and the question of QoS in the wireless networks are explained in a detailed way. The first part of the practical measurement is focused on the networks 802.11b/g/n. All main network statistics are measured when using the wireless stations and routers. The projection and implementation of the wireless network in the Opnet Modeler is included in the next part. The individual simulations WLAN in the Opnet Modeler are comparing the networks 802.11a/b/g. The analysis of the key QoS statistics is undertaken; the measured data are clearly displayed in the charts and schemes. The interpreted results are concluded and justified.
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Figurny, Roman. "Podpora QoS v MANET sítích." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219468.
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The theoretical part of Master's thesis has been dealing with issues of MANET networks, issues of providing quality of services in MANET networks and analysis of various implementations of quality of services in these networks. At the start of the practical part of this thesis was described modified OLSR process model with support of quality of services. In simulation program OPNET Modeler was designed a topology of MANET network, firstly was run a simulation of this network without any support of quality of services and then was run a simulation with support of quality of services. The results of these simulations were analyzed, compared and graphically interpreted. In the next part of this thesis was designed a real MANET network with OLSR support. OLSR network communication was captured with the use of Wireshark. In the last part of this thesis was firstly described a meaning and functions of plugins in OLSR implementation and then was developed a plugin which is responsible for sending messages which contain a state of the links between nodes of MANET networks.
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Filla, Michal. "Návrh QMS v malé organizaci." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228038.
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This Diploma thesis is engaged in implementation of quality management system in a small organization. In this thesis is closely described quality management system, its advantages and rules. There was made an entry analysis and documentation was checked and completed.
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Husák, Adam. "Zlepšení QMS organizace aplikací DMAIC." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230527.
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The aim of this master´s thesis is to design an action to improve of selected process Design and development through DMAIC application. The thesis is focused on identifying the problem, finding the cause and following design of improves leading to eliminate problems. This improves will enable the company to achieve time savings during the process and reduce a risk of orders. Result of this is effective operation in the process.
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Heger, Jan. "Návrh QMS v malé organizaci." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230994.
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The thesis suggests quality management for small organizations and focuses on its implementation, using the DMAIC methodology in accordance with ČSN EN ISO 9001. First, a chosen small organization will be analysed; next, the key processes will be defined and their setting in accordance with ČSN EN ISO 9001 provided.
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Islam, Mohammad Kamrul. "QoS In Parallel Job Scheduling." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1218566682.
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Adepu, Sagarika. "Qos Aware Service Oriented Architecture." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc500032/.
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Service-oriented architecture enables web services to operate in a loosely-coupled setting and provides an environment for dynamic discovery and use of services over a network using standards such as WSDL, SOAP, and UDDI. Web service has both functional and non-functional characteristics. This thesis work proposes to add QoS descriptions (non-functional properties) to WSDL and compose various services to form a business process. This composition of web services also considers QoS properties along with functional properties and the composed services can again be published as a new Web Service and can be part of any other composition using Composed WSDL.
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Nourizadeh, Shahram. "Un système de télésanté contextuel avec support de qualité de service pour le maintien à domicile." Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL044N/document.
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Cette thèse est une thèse CIFRE entre le LORIA et la société MEDETIC et porte sur la conception des systèmes de télésurveillance pour le maintien à domicile des personnes âgées.Le système est conçu aux personnes âgées qui veulent passer leur vieillesse dans leur propre maison, à cause de son potentiel pour augmenter l'indépendance et la qualité de la vie. Cela profiterait non seulement aux personnes âgées qui veulent vivre dans leur propre maison, mais aussi le système de santé publique en coupant des prix de façon significative.Mis à part la conception d'une architecture de télésurveillance « Vill’Âge® »basée sur des réseaux de capteurs hétérogènes (Domotique, IEEE802.15.4/Zigbee, Wifi, Bluetooth), la thèse a contribué essentiellement sur la proposition d'un protocole de clustering et de routage dans le réseau de capteurs sans fil avec une approche de la logique floue, et d'un middleware pour la collecte et le traitement des données des capteurs avec la gestion de la qualité de service comme particularité.Une première plateforme de test à été développée à Colmar (MEDETIC) et une seconde, plus complète et fait suite de cette thèse, est en cours de développement au LORIA (http://infositu.loria.fr/).Nous avons participé dans le concours de ministère de l'Enseignement supérieur et de la recherche avec un projet intitulé MPIGate: « Multi Protocol Interface and Gateway for telecare, environment Monitoring and Control » et nous avons gagné le prix de ce concours au niveau d’émergenceThis thesis is a thesis CIFRE between LORIA and the MEDETIC Company and focuses on the design of telehomecare system for the elderly.In addition to the design of a remote surveillance architecture “Vill’Âge ®” based on networks of heterogeneous sensor (home automation, IEEE802.15.4/Zigbee, Wifi, Bluetooth), thesis has contributed essentially on the proposal of a clustering and routing protocol in the network of wireless sensors with an approach to fuzzy logic, and of a middleware for the collection and processing of data from sensors with the management of the quality of service as a special feature.A first platform was developed at Colmar (MEDETIC) and a second who is more complete is under development at LORIA (http://infositu.loria.fr/).By using this system, MEDeTIC, offers a new concept of smart homes for the senior citizens, named in French “Maisons Vill’Âge”. The first housing schemes are being built in 2 departments of France. A flat is entirely equipped to act as a demonstrator and as laboratory of research and development.The system is designed for the elderly who wish to spend their old age in their own home, because of its potential to increase independence and quality of life. This would not only benefit the elderly who want to live in their own home, but also the national health care system by cutting costs significantly. Based on this PhD thesis, MPIGate, a “Multiprotocol Interface and Gateway for for telecare, environment”, has been developed. MPIGate was awarded in the competition of the Ministry of Higher Education and Research and OSEO 2010
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Frikha, Ahmed. "On providing Qos and reliability for telecommunication networks : multi-domain Qos routing and multicast reliability." Rennes 1, 2012. http://www.theses.fr/2012REN1S067.
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Dans cette thèse, nous étudions deux problèmes majeurs dans les réseaux de télécommunications actuels. Tout d'abord, nous étudions le problème de la fourniture de la qualité de service (QoS) pour les nouvelles applications dans des réseaux multi-domaines. Précisément, le problème de calcul de chemins inter-domaine et multi-contrainte (ID-MCP) est profondément étudié dans la première partie de cette thèse. Dans la deuxième partie, nous étudions la fiabilité des communications dans les réseaux, qui est essentielle pour les services à contraintes strictes. Plus précisément, nous abordons le problème de la garantie de fiabilité des communications multicast. En effet les conséquences d'une panne d'un nœud ou d'un lien dans ce cas d'étude est grave puisque plusieurs destinations peuvent être déconnectées simultanément à la suite d'une seule panne. L'objectif de la première partie est de trouver des nouvelles approches qui permettent de résoudre le problème ID-MCP (inter-domain multi-constrained path computation problem), tout en respectant les politiques des opérateurs des réseaux, à savoir préserver la confidentialité des informations de routage et l'autonomie des domaines. Nous proposons trois nouveaux algorithmes basés sur les éléments de calcul de chemins (PCEs), algorithmes nommés respectivement: ID-PPPA, ID-MEFPA et HID-MCP. Les deux premiers algorithmes utilisent le pré-calcul qui permet de réduire le temps de calcul tout en maintenant un taux de succès élevé. Le troisième algorithme est basé sur un calcul hybride qui bénéficie à la fois des avantages du pré-calcul et du calcul à la demande. L'algorithme HID-MCP utilise des mécanismes de retour en arrière (crankback) pour améliorer le taux de succès global. Les performances de nos algorithmes proposés sont prouvées avec précision par des études analytiques et des simulations. L'objectif de la deuxième partie est de trouver des structures de protection des nœuds et des liens adaptées à la diffusion multicast. Comme le temps de restauration est un critère important dans le processus de reprise de routage (recovery), nous proposons l'étude de la protection des communications multicast au niveau de la couche optique DWDM. Une nouvelle génération de p-cycles adaptés à la structure de diffusion multicast et aux contraintes imposées par les réseaux tout-optiques, est proposée dans cette partie. Nous proposons également trois nouveaux algorithmes pour la protection des nœuds et des liens dans un trafic multicast dynamique, algorithmes nommés respectivement CCHN, NPCC et NPCC-SSC. Le premier algorithme utilise un ensemble de p-cycles candidats bien sélectionnés afin de réduire le temps de calcul et d'optimiser l'utilisation de la bande passante. Différentes approches pour la sélection des ensembles de p-cycles candidats sont étudiées. Le deuxième algorithme NPCC étend le concept de protection des nœuds avec les p-cycles pour une structure de diffusion multicast. Le troisième algorithme étend notre algorithme NPCC pour résoudre les contraintes imposées par les réseaux tout-optiques, telles que le nombre limité de commutateurs optiques capables de splitter un signal lumineux et la contrainte de continuité de la longueur d'onde. Les simulations prouvent que nos algorithmes peuvent assurer une bonne utilisation des ressources ainsi qu'une faible probabilité de blocage tout en réduisant le temps de calculIn this thesis, we study two major problems of today’s telecom networks. First, we study the problem of providing Quality of Service (QoS) guarantees for IP-based services in multi-domain networks. Precisely, the Inter-Domain Multi-Constrained Path (ID-MCP) computation problem is deeply investigated in the first part of this thesis. Second, we study networks reliability, which is essential for many services, namely mission-critical services. Specifically, we address the problem of ensuring reliable multicast communications. Indeed, the consequences of a node or link failure are dramatic in this case of study as multiple destinations could be disconnected simultaneously. The objective of the first part is to find new schemes that enable solving the ID-MCP problem while respecting the operators policies, namely preserving the routing information confidentiality and the autonomy of the domains. We propose three new algorithms based on the Path Computation Element (PCE) framework, named respectively : ID-PPPA, ID-MEFPA and HID-MCP. The first two algorithms employ a pre-computation scheme that allows the computational time to be reduced while maintaining a good acceptance rate of the requests. The third algorithm is based on a hybrid computation scheme that takes advantages from the pre-computation and the on-demand computation. The HID-MCP employs crankback mechanisms to improve the global success rate. Performances of our proposed algorithms are accurately proven through both analytical studies and simulations. The objective of the second part is to find node and link protection structures suitable for multicast diffusion. As the restoration time is a crucial criteria in the recovery process, we address the reliability of multicast communications at the DWDM optical layer. A new generation of p-cycles adapted for multicast diffusion structures as well as the constraints imposed by all-optical networks, is proposed in this part. We also proposed three new algorithms for node and link failure recovery in dynamic multicast traffic, named respectively CCHN, NPCC and NPCC-SSC. The first algorithm uses a set of well-selected candidate p-cycles in order to reduce the computational time and achieve a significant bandwidth saving. Different approaches for selecting the candidate p-cycle sets are investigated. The second algorithm, NPCC, extends the node protection concept of p-cycles for multicast traffic. The third algorithm extends our NPCC algorithm to deal with the constraints imposed by all-optical networks, such as sparse light-splitting and wavelength continuity constraints. Simulation results prove the efficiency of our algorithms in terms of resource utilization, blocking probability and the computational time
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Raphuthing, Manneheng Violet. "Association between geophagia and haematological parameters of iron deficiency anaemia amongst geophagic Qwa-Qwa women." Thesis, Bloemfontein: Central University of Technology, Free State, 2015. http://hdl.handle.net/11462/239.
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Thesis (M. Tech. (Biomedical Technology)) -- Central University of Technology, Free State, [2014]Pica is the habitual eating of non-food substances by humans and animals. It has different subgroups and these are defined by the ingested substance. Moreover, geophagia is a type of pica that refers to the consistent eating of mostly earth and earth-like substances such as clay and soil. It is observed in both sexes, all age groups and in different ethnic groups around the world. There are many reasons people give for the practice of geophagia, such as culture, hunger and health being the most prominent. Geophagic materials differ in texture, colour and taste. Soil colour classification according to the Munsell soil classification, which uses hues, values and chroma, sometimes differ with the soil colour being noticeable with the naked eye. However, geophagic clays from Qwa-Qwa are white and contain kaoline. Geophagic materials are believed to augment mineral deficiency, especially magnesium, calcium and iron. Geophagia is practised mainly by females, especially during their child bearing years. Females are more prone to iron deficiency anaemia due to their monthly menstruation cycle. Iron deficiency is the most common cause of anaemia and is classified as hypochromic microcytic anaemia (HMA). This study focused on the health aspect of geophagia. The research question seeks to explore whether there is an association between geophagia and the haematological parameters of iron deficiency anaemia. Geophagia seems to be linked with the occurrence of anaemia, but not iron deficiency anaemia, although it is implied. It is not known if the practice of geophagia causes iron deficiency anaemia or if it is because of iron deficiency anaemia that people practise geophagia. A pilot study was done in 2007, and the results of that study prompted that this study be performed on a bigger scale. The lack of information regarding the quantity, frequency and type of geophagic material consumed the impact of geophagia on haematological parameters and the iron status of the geophagists made it important that the primary existence of the iii relationship be investigated. In addition, research to establish whether there is a relationship between geophagia and haematological parameters of iron deficiency anaemia, has not been undertaken in South Africa, especially on non-pregnant women. Geophagia seems to always be accompanied by the subject of iron deficiency anaemia and especially its prevalence in females. The bigger geophagia project was therefore an ideal opportunity to do a specific survey on geophagic women. This was a cross-sectional study, consisting of 36 control women and 47 geophagic women, aged between 18-45 years. The participants completed a questionnaire to determine the geophagic practices, which included the colour of the clay, how frequent the clay was consumed, how much was consumed and for how long it has been consumed. Nutritional status was assessed using a food frequency questionnaire. Blood was drawn to assess the haematological and iron status of the participants. The participants of the study were within the required age range, with no significant difference between the groups (p-value=0.7914). The most consumed colour of clay was white and white clay contains kaoline, which has the ability to absorb iron in the duodenum. The majority of the participants consumed 40 grams of clay on a daily basis, with most of the participants having done so for 5 years. Diet was ruled out as the cause of iron deficiency. The haematological parameters indicated that the geophagic group (43%) were inclined to have hypochromic microcytic anaemia, while a small percentage of control groups (8%) had HMA; this was revealed by the red cell parameters and red cell indices. In addition, the odds ratio for the haematological results revealed that the probability of a geophagic person developing anaemia was two times greater than that of a non-geophagic person. Platelet results partially ruled out bleeding as a cause of anaemia. The median red cell distribution width indicated that the iv geophagic group was inclined to have anisocytosis. The geophagic group was found to have iron deficiency (75%), whilst the control group had a small percentage with iron deficiency (22%), which was validated by the serum ferritin, serum iron and saturated transferrin (chemical analysis). The odds ratio revealed that the probability of a geophagic person being iron deficient is 3 times greater than that of a non-geophagic person. The strongest association is seen with iron study findings, because being iron deficient showed the highest odd ratio than the association with red cell morphology and even haemoglobin. Thus, participants were more iron deficient than suffering from iron deficiency anaemia. Inflammatory and parasitic indicators proved that inflammation and infection was uncommon in both groups, and therefore did not compromise the credibility of the iron study results. Inflammatory indicators (white blood cells, erythrocyte sedimentation rate and C-reactive protein) ruled out inflammation, whilst eosinophil count showed no indication of parasitic infection for both geophagic and control groups. To conclude, the study found that an association exists between geophagia and haematological parameters of iron deficiency anaemia amongst geophagic women in Qwa-Qwa, in that geophagic material contributes to iron deficiency anaemia.
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Casagrande, Lucas dos Santos. "Política de escalonamento de tempo real baseada em exigência para provisão de QoS absoluto em serviços Web." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-12092007-155501/.
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Este trabalho apresenta um estudo, implementação e validação em ambiente simulado de uma política de escalonamento de tempo real para provisão de QoS absoluto em serviço Web. Sintetizando características de escalonamento de tempo real, com baixa latência e de modelo re-alimentado, a política proposta permite um ajuste ponderado pela quantificação da exigência à qual o sistema está submetido por meio de suas classes. A meta é oferecer ações imediatas às requisições mais urgentes, sem, entretanto, degradar a qualidade do sistema como um todo. Verificou-se que a estratégia de escalonamento baseada em exigência (EBS - Exigency-Based Scheduling) é benéfica para o controle da qualidade de serviço oferecida. Escalonar de forma a evitar demasiado peso imposto ao sistema permite que o servidor tenha mais condições de cumprir os requisitos contratuais. Também foi alvo do estudo a criação de uma métrica de avaliação da satisfação de atendimento por parte dos usuários dos serviços. Os resultados alcançados com o emprego da política EBS sinalizam uma melhoria em termos de qualidade de serviço e melhor satisfação dos clientes de forma balanceadaThe present work presents a study, implementation and validation in a simulated environment of a real time scheduling policy to provide absolute QoS for web services. Synthesizing characteristic from real time scheduling, low latency and feedback scheduling, the proposed policy allows an adjustment weighed by the quantification of the exigency which the system is exposed through its classes. The goal is to offer immediate actions to most urgent requests, without decreasing the system quality as a whole. It was verified that the scheduling strategy based on exigency (EBS - Exigency-Based Scheduling) helps to control the quality of service offered. Scheduling in order to avoid imposing a heavy load to the system gives more condition to the server to fulfill the requirements agreed. Another goal of this work is the creation of a metrics to evaluate the client satisfaction. The results achieved with the EBS policy indicate a higher quality of service and better client satisfaction
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Nakamuta, Alessandro. "Avaliação de desempenho da política EBS em uma arquitetura de escalonamento realimentada." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-24072012-104123/.
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Este trabalho apresenta uma avaliação do algoritmo EBS, uma política de escalonamento proposta para sistemas de tempo real flexíveis com qualidade de serviço baseado em limites superiores para tempos médios de resposta. Experimentos têm demonstrado propriedades vantajosas da política EBS em servidores Web com diferenciação de serviço. O objetivo do presente estudo é compreender o comportamento da EBS em relação à diferentes parâmetros que descrevem a carga de trabalho. Esse conhecimento é útil para obtenção de um melhor aproveitamento computacional. São apresentados experimentos e resultados que analisam a influência de cada um dos fatores considerados na qualidade do serviço oferecido. A partir desses resultados são tecidas conclusões acerca de abordagens para o dimensionamento de carga e de capacidade do servidorThis Master degree project has presented an evaluation of the EBS algorithm, a scheduling policy proposed for soft real-time systems with quality of service based on upper limits for average response times. Experiments have shown advantageous properties of the EBS policy on Web servers with service differentiation. The aim of this study is to understand the behavior of the EBS in relation to different parameters that describe the workload. This knowledge is useful for obtaining a better use of computing. Experiments and results are presented analyzing the influence of each factor considering the quality of service offered. From these results, conclusions are woven about approaches to the design load and server capacity
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Bereketli, Alper. "On Qos Multicast Routing Routing Protocols." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606446/index.pdf.
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Multicasting is a technique used for distributing data packets from one or more sources to a set of receivers on interconnected networks. Currently developing network applications bring specific quality of service (QoS) requirements like bounded delay, minimum bandwidth, and maximum data loss rate. Providing the required quality of service addresses routing and resource reservation concepts. In this study, a literature survey is carried out on traditional and QoS multicast routing protocols, and the need for QoS routing protocols is investigated. QoS multicast routing protocols are classified and compared according to their multicast tree construction and resource reservation approaches. Two QoS protocols, QROUTE and QMBF, are selected, and their performances are experimentally compared using the network simulation tool Network Simulator-2 (ns-2). The objective of the simulations is to compare the QoS routing algorithms and their tree construction efficiencies. The first contribution of the thesis is the survey and classification of traditional and QoS multicast routing protocols. Another contribution is the ns-2 implementation of two QoS multicast routing protocols. The final contribution of the thesis is the performance evaluation of the recent protocols from a different perspective.