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Total distans och högintensiva löpningar, en framgångsfaktor inom fotbollen? : En kvantitativ undersökning för dam VM 2015 och herr VM 2018Johansson, Ludwig, Egegård, Andreas January 2020 (has links)
Syfte och frågeställningar Syftet med studien är att undersöka om det förekommer något samband mellan total distans, högintensiva löpningar och totalt inspelade poäng i damernas och herrarnas FIFA World Cup år 2015 respektive 2018. Vidare avser författarna att undersöka om damernas och herrarnas totala distans skiljer sig mellan respektive FIFA World Cup. Området är en viktig del av dagens fotboll och resultaten i studien är användbara för tränare, spelare och fotbollsverksamheter. Studiens frågeställningar är därför: Förekommer det något samband mellan poäng och total distans i damernas och herrarnas FIFA World Cup från 2015 respektive 2018? Förekommer det något samband mellan poäng och högintensiva löpningar i damernas och herrarnas FIFA World Cup från 2015 respektive 2018? Skiljer sig den totala distansen mellan damer och herrar under FIFA World Cup 2015 respektive 2018? Metod Studien genomfördes med en kvantitativ metod och en retrospektiv studiedesign. I studien analyserades 200st fotbollsmatcher, som motsvarar alla spelade matcher vid damernas och herrarnas FIFA World Cup 2015 respektive 2018. Data som analyserades var total distans, högintensiva löpningar och poäng. Datainsamlingen gjordes genom FIFAs officiellt publicerade rapporter gällande respektive FIFA World Cup. Resultat Resultaten visade en signifikant korrelation mellan total distans och poäng samt högintensiva löpningar och poäng för damernas FIFA World Cup. Inget samband upptäcktes med likadana analyser under herrarnas FIFA World Cup. Studien upptäckte en skillnad mellan damernas och herrarnas totala distans, där distansen var längre för damer jämfört med herrar (p= 0,003). Slutsats Studien påvisar skillnader mellan dam- och herrfotboll. Den fysiska förmågan verkar ha större betydelse för matchavgörande i damernas 2015 jämfört med herrarnas FIFA World Cup 2018. Resultaten som redovisas lämnar utrymme för argumentet att damfotbollen bör tillämpa träningsplaneringar som kopplas till spelares fysiska kapacitet. / <p>Ämneslärarprogrammet, Specialidrott</p>
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Comparison of GCP and AWS using usability heuristic and cognitive walkthrough while creating and launching Virtual Machine instances in VirtualPrivate CloudCherukuri, Prudhvi Nath Naidu, Ganja, Sree Kavya January 2021 (has links)
ABSTRACT Cloud computing has become increasingly important over the years, as the need for computational resources, data storage, and networking capabilities in the field of information technology has been increased. There are several large corporations that offer these services to small companies or to end-users such as GCP, AWS, Microsoft Azure, IBM Cloud, and many more. The main aim of this thesis is to perform the comparison of GCP and AWS consoles in terms of the user interface while performing tasks related to compute engine. The cognitive walkthrough has been performed on tasks such as the creation of VPC, creation of VM instances, and launching them and then from the results, both the interfaces are compared using usability heuristics. Background: As the usage of cloud computing has increased over the years, the companies that are offering these services have grown eventually. Though there are many cloud services available in the market the user might always choose the services that are more flexible and efficient to use. In this manner, the choice of our research is made to compare the cloud services in terms of user interaction user experience. As we dig deep into the topic of user interaction and experience there are evaluation techniques and principles such as cognitive walkthrough and usability heuristics are suitable for our research. Here the comparison is made among GCP and AWS user interfaces while performing some tasks related to compute engine. Objectives: The main objectives of this thesis are to create VPC, VM instances,s and launch VM instances in two different cloud services such as GCP and AWS. To find out the best user interface among these two cloud services from the perspective of the user. Method: The process of finding best user interface among GCP and AWS cloud services is based on the cognitive walkthrough and comparing with usability heuristics. The cognitive walkthrough is performed on chosen tasks in both the services and then compared using usability heuristics to get the results of our research. Results: The results that are obtained from cognitive walkthrough and comparison with usability heuristics shown in graphical formats such as bar graphs, pie charts, and the comparison results are shown in the form of tabular form. The results cannot be universal, as they are just observational results from cognitive walkthrough and usability heuristic evaluation. Conclusion: After performing the above-mentioned methods it is observed that the user interface of GCP is more flexible and efficient in terms of user interaction and experience. Though the user experience may vary based on the experience level of users in cloud services, as per our research the novice user and moderate users have chosen GCP as a better interactive system over AWS. Keywords: Cloud computing, VM instance, Cognitive walkthrough, Usability heuristics, User-interface.
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Enriching the internet control-plane for improved traffic engineering / Amélioration du plan de contrôle d'internet avec de nouvelles solutions d'ingénierie de traficPhung, Chi Dung 30 March 2018 (has links)
L'un des défis majeurs de l'évolution de l'architecture Internet est la définition d'une architecture protocolaire permettant d'améliorer le routage, et en particulier (i) conserver un système de routage gérable avec les technologies actuelles et futures c'est-à-dire, avec quelques millions d'états, (ii) offrir une architecture apte à faciliter la programmabilité du plan de transfert, (iii) proposer un système de routage évolutif pouvant être régulièrement optimisé avec uniquement les informations sur les flux actifs, (iv) fournir une séparation entre localisateurs et identificateurs pour la mobilité IP avancée, (v) faciliter un déploiement incrémental, (vi) mieux servir les services applicatifs "over-the-top". Le protocole LISP (\textit{Locator/Identifier Separation Protocol}) a été identifié comme l'un des protocoles émergents à cet égard. Dans son état actuel, il répond très bien aux besoins susmentionnés. Cependant, il subit des limitations lorsqu'il s'agit de prendre en compte la résilience et la capacité à réagir rapidement aux mises à jour de l'état du réseau. Ces inconvénients peuvent être compensés en améliorant l'architecture du plan de contrôle et ses algorithmes de routage. Dans cette thèse, nous proposons une nouvelle architecture réseau-système et expérimentons de nouvelles primitives de plan de contrôle, ainsi que d'algorithmes de diffusion des états, en testant son passage à l'échelle avec différentes conditions de réseau. Nous concevons et construisons d'abord un nœud de plan de données et de plan de contrôle LISP open source. Nous le comparons avec d'autres implémentations en montrant que notre implémentation atteint des performances adaptées aux vrais déploiements. Nous montrons comment notre implémentation a permis la mise en oeuvre d'une plateforme d'expérimentation à grande échelle, la plate-forme LISP-Lab, en opération aussi bien les fonctions de plan de transfert que les fonctions de plan de contrôle. En suite, nous proposons une nouvelle solution pour les migrations à chaud de machines virtuelles à travers des centres de données géographiquement répartis sur des réseaux IP étendus. Des tests dans un testbed réel connecté nativement à Internet montrent qu'avec notre approche, nous pouvons facilement atteindre des temps d'arrêt inférieurs à la seconde lors de la migration sur une grande échelle, même pour des clients très distants. En outre, nous avons étudié des protocoles d'optimisation de réseau multicouche, en particulier en relation avec le protocole MPTCP (Multipath Transport Control Protocol), auquel LISP peut offrir une diversité de chemins pour l’agrégation de bande passante, ainsi qu’une plus grande confidentialité et fiabilité des connexions. Bien que nous ne puissions bénéficier que de quelques nœuds de réseau superposés, nous avons pu évaluer expérimentalement nos propositions en montrant l'impact positif de notre solution, l'impact négatif des longs temps d'aller-rétour sur certains sous-flux MPTCP, et la forte corrélation entre le temps d'aller-retour différentiel et le débit. Enfin, nous avons travaillé sur une refonte du plan de contrôle de LISP afin d’améliorer son fonctionnement du à l'échelle d’Internet, en facilitant la coopération entre les systèmes de mapping LISP et en introduisant plus d'automatisation dans la procédure de fourniture de services de connectivité LISP. Nous croyons qu'une telle optimisation pourrait sensibiliser la communauté des fournisseurs de services, générant de nouvelles opportunités commerciales liées aux services de cartographie LISP et l'application de politiques d'ingénierie de trafic interdomaines avancées dans le but d'obtenir de meilleures garanties de qualité de service. / One of the major challenges in the evolution of the Internet architecture is the definition of a protocol architecture that allows to solve the following major issues in Internet routing and traffic forwarding capabilities, (i) keeping a routing state that is manageable with current and forthcoming computing infrastructure – i.e., with few millions of states, (ii) offering a scalable pull architecture in support of data-plane programmability, (iii) offering a scalable forwarding plane able to be regularly optimized with only active flows information, (iv) offering locator/identifier separation for advanced IP mobility, (v) is incrementally deployable, (vi) can enhance the support of over-the-top services. The Locator/Identifier Separation Protocol (LISP) has been identified as one of the rising protocols in this respect. In its current status, it supports the above mentioned requirements at a level that is acceptable for basic networking environments. However, it shows too limited capacities when it comes to take into consideration fault resiliency and capability to react fast to network state updates. These shortcomings can be compensated by enhancing the control-plane architecture, and the routing algorithms therein. In this dissertation, we propose new protocol features and experiment novel control-plane primitives, as well as hybrid distributed-centralized routing state dissemination algorithms, to scale with different network conditions. We first design and build own open source LISP data-plane and control plane node, comparing it with other implementations, showing how our implementation can scale for large networks and reach performances suitable for real deployments. We present how our implementation served to operate all network nodes (data-plane and control-plane nodes) of a large scale experimentation testbed, the LISP-Lab testbed. Then we propose a novel LISP-based solution for VM live migrations across geographically separated datacenters over wide area IP networks. Experimenting it at large scale, we show that with our approach we can easily reach sub-second downtimes upon Internet-wide migration, even for very distant clients. Moreover, we investigate cross-layer network optimization protocols, in particular in relation with the Multipath Transport Control Protocol (MPTCP) to which LISP can deliver path diversity in support of bandwidth increase, confidentiality support and connection reliability, also using LISP traffic engineering network overlays. Despite we could benefit from only few overlay network nodes, we could experimentally evaluate our proposals showing the positive impact by using our solution, the negative impact of long round-trip times on some MPTCP subflows, and the strong correlation between the differential round-trip time among subflows and the throughput performance. Finally, we worked on a framework to improve LISP operation at the Internet scale, by facilitating cooperation between LISP Mapping Systems and introducing more automation in the LISP connectivity service delivery procedure. We believe such optimization could raise awareness among the service providers’ community, yielding new business opportunities related to LISP mapping services and the enforcement of advanced inter-domain traffic engineering policies for the sake of better quality of service guarantees.
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Fotboll och politik : En kvalitativ undersökning om hur rapporteringen av landslag från MENA-regionen respektive Europa konstrueras inom svensk sportjournalistik i samband med fotbolls-VM i Qatar 2022Ibrahim, Suleiman January 2023 (has links)
Tidigare forskning har visat att medias rapportering om olika länder, kulturer och etniciteter skiljer sig åt beroende på vad och vilka som porträtteras, vilket i synnerhet förtydligas kring framställningen av avvikande kulturer. Kunskap kring dessa förhållanden problematiseras även i sportsliga sammanhang, där forskning bland annat tittat närmare på medierepresentation utifrån ett ”vi” och ”dem”-tänkande. Information kring hur media valt att konstruera landslag utifrån ett regionalt perspektiv, är dock inte lika utbrett. Denna studies syfte är därför att undersöka hur landslag under fotbolls-VM i Qatar 2022 porträtteras inom svensk sportjournalistik. Vidare behandlar studiens frågeställningar mer specifikt hur landslag från MENA-regionen (en engelskspråkig förkortning av länder från ”Mellanöstern och Nordafrika”), respektive Europa konstrueras i Expressen och Aftonbladets rapporteringar, och hur dessa skildringar kan förstås utifrån ett postkolonialt perspektiv. För att på ett djupare plan analysera dessa mediers rapporteringar, har diskursteorin tillämpats i undersökningen. Samtidigt har den postkoloniala teorin använts för att utröna historiska och kulturella förklaringar till mediernas skildringar. En kritisk diskursanalys har vidare tillämpats som metod för denna studie, med utgångspunkt i ett analysschema. Resultatet visar att svensk sportjournalistik avviker i sin rapportering under mästerskapet, där yttre faktorer såsom politiska aspekter i stor utsträckning syns i texterna som behandlar landslagen från MENA-regionen. Medan sportsliga företeelser i synnerhet kommer till bruk i texterna som redogör för europeiska landslag. Studien visar även att de sportsliga resultaten redogörs på olika sätt beroende på vilka landslag som det rapporteras om. Anledningarna till dessa olikartade skildringar kan möjligen förklaras i den kulturella närhet respektive avstånd, som svensk sportjournalistik har till Europa (västerlandet), samt MENA-regionen (orienten).
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Från individuella hjältedåd till kollektiv gemenskap : En kvalitativ kritisk diskursanalys om framställningen av det svenska damlandslaget i fotboll i tidningarna Aftonbladet och Expressen under två världsmästerskap. / From individual acts of heroism to collective communityLindbäck, Ellen, Lönnegren, Thelma January 2024 (has links)
Fotboll är den sporten världen över som har störst dragningskraft, både på dam- och herrsidan, vad gäller utövare och åskådare (NE, u.å.). Trots att det är en idrott för både damer och herrar, och att det svenska damlandslaget i fotboll har presterat på en hög nivå under en lång tid (FIFA, u.å.), är kvinnor underrepresenterade vad gäller medieexponering (Kian et al., 2011). Studien utgår från artiklar från Aftonbladet och Expressen skrivna under världsmästerskapet för damer 2011 och världsmästerskapet för damer 2023. Totalt åtta artiklar, två artiklar från vardera tidning och år, analyseras med hjälp av en kritisk diskursanalys. Analysen görs utifrån ett genus- och gestaltningsteoretiskt synsätt samt med hjälp av kritisk diskursanalys som teori. Undersökningen görs för att besvara studiens forskningsfråga: Hur har medieporträtteringen av Sveriges damlandslag i fotboll förändrats mellan VM 2011 och VM 2023 i Aftonbladet och Expressen, gällande framställningen av spelarna och deras prestationer? Det empiriska materialet analyseras utifrån ett analysschema bestående av analysdimensionerna: Textens huvudsakliga innehåll och omgivande struktur, språk i detalj samt diskursiva strategier. Resultatet av studien visar att det ur vissa aspekter har skett en förändring vad gäller det svenska damlandslagets framställning i medier. De mest märkbara förändringarna är gestaltningen av gemenskap inom fotbollen internationellt och inom det svenska damlandslaget samt sättet att beskriva spelarnas emotionella uttryck. Ingen av artiklarna använde könsspecifika beskrivningar av damfotbollsspelarna, varken 2011 eller 2023, vilket därmed visar på att det inte skett någon förändring gällande det, utifrån det empiriska material som studerats. Vidare diskuteras studiens resultat kopplat till bakgrund och tidigare forskning gällande jämställdhet och ordval. / Football is the sport worldwide that has the greatest appeal in terms of players and spectators, both on the women’s and men’s side (Nationalencyklopedin [NE], u.å.). Despite being a sport for both women and men and the fact that the Swedish women’s national football team have been performing at a high level (FIFA, u.å.), women are underrepresented in terms of media exposure (Kian et al., 2011). The study is based on articles from the Swedish newspapers Aftonbladet and Expressen written during the Women’s World Cup 2011 and 2023. Two articles from each newspaper and year are analyzed, using critical discourse analysis. The study is supposed to answer the research question: How has the media portrayal of the Swedish women’s national football team changed between the 2011 and 2023 World Cups in Aftonbladet and Expressen, regarding the representation of the players and their performances? The empirical material is analyzed based on an analysis framework with the dimensions: the main content and surrounding structure of the text, language in detail and discursive strategies. The result of the study showed that, from certain aspects, there was a change in the portrayal of the Swedish women’s national football team in the media. The most noticeable changes are the representation of community, both international and within the Swedish national team and the way the media describes the players’ emotional expressions. None of the articles used gender-specific descriptions of female football players, neither in 2011 nor in 2023, which thus shows that there has been no change regarding it, based on the empirical material that was studied.
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Fotboll och Postkolonialism : En Komparativ Fallstudie av Svensk Media och dess Rapportering om Fotboll-VM 2018 och 2022 / Football and Postcolonialism : A Comparative Case Study of the Swedish Media and its Reporting of the Football World Cup 2018 and 2022Karlelid, Lukas January 2023 (has links)
From the very beginning, there were negative reactions when Qatar and Russia were chosento host a FIFA World Cup each. The criticism against both World Cups grew over time,thanks in no small part due to how migrant workers building the stadiums in both countrieswere treated. The purpose of this thesis has been to examine whether or not Edward Said'stheory of postcolonialism and Imannuel Wallerstein's theory on civilization in eurocentrismhave played a part in how the Swedish media chose to cover both World Cups. In this thesis,the two biggest newspapers in Sweden, “Aftonbladet” and “Dagens Nyheter” were used inthe analysis. The method used was a comparative case study, in which articles and quotesregarding Qatar and Russia were compared and then analyzed. The analysis revealed that,although these theories and stereotypes could have played a role in how the Swedish mediareported on the World Cups, the results were inconclusive, meaning that no conclusion onwhether postcolonial or eurocentric stereotypes played a role in the media coverage could beconfirmed.
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Könsstereotyper i förändring : En jämförelse av mediebevakningen av svenska damlandslaget i fotboll under VM 2003 och 2023Olsson, Rut, Strömberg, Tova January 2024 (has links)
This study aims to examine how the Swedish national team in football was portrayed in a Swedish newspaper during the FIFA Women's World Cup 2003 and 2023. The main focus was to examine if there were any similarities or differences in the portrayal from a gender perspective. The study aims to understand whether and how gender stereotypes exist and change in sports journalism. The empirical material consists of ten articles published in Dagens Nyheter, five from each championship. A qualitative linguistic text analysis was used to analyze the articles from a linguistic perspective to uncover underlying values and meanings. The study uses a theoretical framework consisting of Hirdman's gender system and gender contract (2003, 2004), Lippmann's stereotypes (2012), and Entman's framing theory (1993). The findings revealed both differences and similarities in the team's portrayal in 2003 and 2023. The reporting in 2023 showed a shift towards focusing less on private lives and appearances compared to 2003, despite the lack of strong patterns in 2003. References to players by their full name were more common in 2023 in comparison to 2003 where the use of only forename and nicknames were more common. Both tournaments consistently emphasized the emotional aspects of the players and also described them based on their athletic achievements. The results show that the reporting on women's football is evolving towards a less stereotypical portrayal, though some stereotypical elements remain, such as the strong focus on the player’s emotions.
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Jämförelse av Hypervisor & Zoner : Belastningstester vid drift av webbservrarNyquist, Johan, Manfredsson, Alexander January 2013 (has links)
Virtualisering av datorer rent generellt innebär att man delar upp hela eller delar av enmaskinkonfiguration i flera exekveringsmiljöer. Det är inte bara datorn i sig som kanvirtualiseras utan även delar av det, såsom minnen, lagring och nätverk. Virtualiseringanvänds ofta för att kunna nyttja systemets resurser mer effektivt. En hypervisorfungerar som ett lager mellan operativsystemet och den underliggande hårdvaran. Meden hypervisor har virtuella maskiner sitt egna operativsystems kärna. En annan tekniksom bortser från detta mellanlager kallas zoner. Zoner är en naturlig del avoperativsystemet och alla instanser delar på samma kärna, vilket inte ger någon extraoverhead. Problemet är att hypervisorn är en resurskrävande teknik. Genom att användazoner kan detta problem undkommas genom att ta bort hypervisorlagret och istället köramed instanser som kommunicerar direkt med operativsystemets kärna. Detta ärteoretiskt grundande och ingen tidigare forskning har utförts, därmed påkallades dennautredning. För att belysa problemet använde vi oss av Apache som webbserver.Verktyget Httperf användes för att kunna utföra belastningstester mot webbservern.Genom att göra detta kunde vi identifiera att den virtualiserade servern presterade sämreän en fysisk server (referensmaskin). Även att den nyare tekniken zoner bidrar till lägreoverhead, vilket gör att systemet presterar bättre än med den traditionella hypervisorn.För att styrka vår teori utfördes två tester. Det första testet bestod utav en virtualiseradserver, andra testet bestod av tre virtuella servrar. Anledningen var att se hur de olikateknikerna presterade vid olika scenarion. Det visade sig i båda fallen att zonerpresterade bättre och att det inte tappade lika mycket i prestanda i förhållande tillreferensmaskinerna. / Virtualization of computers in general means that the whole or parts of a machineconfiguration is split in multiple execution enviornments. It is not just the computeritself that can be virtualized, but also the resources such as memory, storage andnetworking. Virtualization is often used to utilize system resources more efficient. Ahypervisor acts as a layer between the operating system and the underlying hardware.With a hypervisor a virtual machine has its own operating system kernel. Anothertechnique that doesn't use this middle layer is called zones. Zones are a natural part ofthe operating system and all instances share the same core, this does not provide anyadditional overhead. The problem with hypervisors is that it is a rescource-demandingtechnique. The advantage with zones is that you should be able to avoid the problem byremoving the hypervisor layer and instead run instances that communicate directly tothe operating system kernel. This is just a theoretical foundation. No previous researchhas been done, which result in this investigation. To illustrate the problem we usedApache as a web server. Httperf will be used as a tool to benchmark the web server. Bydoing this we were able to identify that the virtualized server did not perform quite aswell as a physical server. Also that the new technique (zones) did contribute with loweroverhead, making the system perform better than the traditional hypervisor. In order toprove our theory two tests were performed. The first test consisted of one virtual serverand the other test consisted of three virtual servers. The reason behind this was to seehow the different techniques performed in different scenarios. In both cases we foundthat zones performed better and did not drop as much performance in relation to ourreference machines.
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Placement autonomique de machines virtuelles sur un système de stockage hybride dans un cloud IaaS / Autonomic virtual machines placement on hybrid storage system in IaaS cloudOuarnoughi, Hamza 03 July 2017 (has links)
Les opérateurs de cloud IaaS (Infrastructure as a Service) proposent à leurs clients des ressources virtualisées (CPU, stockage et réseau) sous forme de machines virtuelles (VM). L’explosion du marché du cloud les a contraints à optimiser très finement l’utilisation de leurs centres de données afin de proposer des services attractifs à moindre coût. En plus des investissements liés à l’achat des infrastructures et de leur coût d’utilisation, la consommation énergétique apparaît comme un point de dépense important (2% de la consommation mondiale) et en constante augmentation. Sa maîtrise représente pour ces opérateurs un levier très intéressant à exploiter. D’un point de vue technique, le contrôle de la consommation énergétique s’appuie essentiellement sur les méthodes de consolidation. Or la plupart d'entre elles ne prennent en compte que l’utilisation CPU des machines physiques (PM) pour le placement de VM. En effet, des études récentes ont montré que les systèmes de stockage et les E/S disque constituent une part considérable de la consommation énergétique d’un centre de données (entre 14% et 40%). Dans cette thèse nous introduisons un nouveau modèle autonomique d’optimisation de placement de VM inspiré de MAPE-K (Monitor, Analyze, Plan, Execute, Knowledge), et prenant en compte en plus du CPU, les E/S des VM ainsi que les systèmes de stockage associés. Ainsi, notre première contribution est relative au développement d’un outil de trace des E/S de VM multi-niveaux. Les traces collectées alimentent, dans l’étape Analyze, un modèle de coût étendu dont l’originalité consiste à prendre en compte le profil d’accès des VM, les caractéristiques du système de stockage, ainsi que les contraintes économiques de l’environnement cloud. Nous analysons par ailleurs les caractéristiques des deux principales classes de stockage, pour aboutir à un modèle hybride exploitant au mieux les avantages de chacune. En effet, les disques durs magnétiques (HDD) sont des supports de stockage à la fois énergivores et peu performants comparés aux unités de calcul. Néanmoins, leur prix par gigaoctet et leur longévité peuvent jouer en leur faveur. Contrairement aux HDD, les disques SSD à base de mémoire flash sont plus performants et consomment peu d’énergie. Leur prix élevé par gigaoctet et leur courte durée de vie (comparés aux HDD) représentent leurs contraintes majeures. L’étape Plan a donné lieu, d’une part, à une extension de l'outil de simulation CloudSim pour la prise en compte des E/S des VM, du caractère hybride du système de stockage, ainsi que la mise en oeuvre du modèle de coût proposé dans l'étape Analyze. Nous avons proposé d’autre part, plusieurs heuristiques se basant sur notre modèle de coût et que nous avons intégrées dans CloudSim. Nous montrons finalement que notre approche permet d’améliorer d’un facteur trois le coût de placement de VM obtenu par les approches existantes. / IaaS cloud providers offer virtualized resources (CPU, storage, and network) as Virtual Machines(VM). The growth and highly competitive nature of this economy has compelled them to optimize the use of their data centers, in order to offer attractive services at a lower cost. In addition to investments related to infrastructure purchase and cost of use, energy efficiency is a major point of expenditure (2% of world consumption) and is constantly increasing. Its control represents a vital opportunity. From a technical point of view, the control of energy consumption is mainly based on consolidation approaches. These approaches, which exclusively take into account the CPU use of physical machines (PM) for the VM placement, present however many drawbacks. Indeed, recent studies have shown that storage systems and disk I/O represent a significant part of the data center energy consumption (between 14% and 40%).In this thesis we propose a new autonomic model for VM placement optimization based on MAPEK (Monitor, Analyze, Plan, Execute, Knowledge) whereby in addition to CPU, VM I/O and related storage systems are considered. Our first contribution proposes a multilevel VM I/O tracer which overcomes the limitations of existing I/O monitoring tools. In the Analyze step, the collected I/O traces are introduced in a cost model which takes into account the VM I/O profile, the storage system characteristics, and the cloud environment constraints. We also analyze the complementarity between the two main storage classes, resulting in a hybrid storage model exploiting the advantages of each. Indeed, Hard Disk Drives (HDD) represent energy-intensive and inefficient devices compared to compute units. However, their low cost per gigabyte and their long lifetime may constitute positive arguments. Unlike HDD, flash-based Solid-State Disks (SSD) are more efficient and consume less power, but their high cost per gigabyte and their short lifetime (compared to HDD) represent major constraints. The Plan phase has initially resulted in an extension of CloudSim to take into account VM I/O, the hybrid nature of the storage system, as well as the implementation of the previously proposed cost model. Secondly, we proposed several heuristics based on our cost model, integrated and evaluated using CloudSim. Finally, we showed that our contribution improves existing approaches of VM placement optimization by a factor of three.
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Strategic volunteer management planning and implementation in Scottish third sector organisations : understanding the volunteer psychological contractWu Berberich, Bing January 2015 (has links)
Third sector organisations (TSOs) have been operating in a turbulent environment of social, political and economic changes, presenting challenges to their continued activities. The volunteer workforce, as a key component of TSOs’ human resource, has long been considered crucial for the sector. Despite this acknowledgement, existing research suggests that TSOs have not effectively managed and supported their volunteer workforce in order to sustain development. There are claims for TSOs to place volunteer management (VM) onto a strategic level, and it is considered crucial for TSO managers, CEOs and volunteer coordinators (VCs) to achieve sustainable organisational development through the strategic planning and implementation of VM practices. However, existing research has focussed more on articulating volunteer motives; and little attention has been paid to considering the ways in which individual perspectives influence effective VM. This study addressed the gap by exploring key players’ (CEO, VC and volunteer) perceptions of the policies, practices and processes used to attract, engage and retain volunteers in small to medium Scottish TSOs. It aimed to provide insights into the importance of strategic VM in sustaining TSO performance and in understanding the crucial role of VCs, through unfolding the processes of making and fulfilling individual volunteer psychological contracts (VPCs). Three case studies were carried out within three Scottish TSOs; in-depth qualitative interviews were conducted with participants occupying different roles, CEO (n=3), VC (n=5) and volunteers (n=16). Supplementary data were obtained through documentary study of VM policies and practices. Data collection was guided by a conceptual framework developed by embedding the Resource Based View (RBV) of HRM and HR devolution to the Line into the process of making and fulfilling the psychological contract. Results support the claim that TSOs would benefit from more strategic management of their volunteer workforce as a competitive resource. Examining VM through the lens of the VPC provided empirical evidence to confirm that it is crucial to engage and retain volunteers by shaping their expectations and motives within the TSO, and thus ensure more sustainable TSO performance. The results further support the salient role of VC as volunteer line manager, in attracting, engaging and retaining volunteers through effective VM implementation. In arriving at these results, this research has extended the theoretical debate on the importance of strategic HR management and the key role that line managers can play in achieving this beyond the more dominant private sector focus.
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