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Gutiérrez, Galeano Alonso. "Study of Photovoltaic System Integration in Microgrids through Real-Time Modeling and Emulation of its Components Using HiLeS." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30178/document.
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L'intégration actuelle des systèmes photovoltaïques dans les systèmes d'alimentation conventionnels a montré une croissance importante, ce qui a favorisé l'expansion rapide des micro-réseaux du terme anglais microgrid. Cette intégration a cependant augmenté la complexité du système d'alimentation qui a conduit à de nouveaux défis de recherche. Certains de ces défis de recherche encouragent le développement d'approches de modélisation innovantes en temps réel capables de faire face à cette complexité croissante. Dans ce contexte, une méthodologie innovante est proposée et basée sur les composants pour la modélisation et l'émulation de systèmes photovoltaïques en temps réel integers aux microgrids. L'approche de modélisation proposée peut utiliser le langage de modélisation des systèmes (SysML) pour décrire la structure et le comportement des systèmes photovoltaïques intégrés en tenant compte de leurs caractéristiques multidisciplinaires. De plus, cette étude présente le cadre de spécification de haut niveau des systèmes embarqués (HiLeS) pour transformer les modèles SysML développés en code source destinés à configurer le matériel intégré. Cette caractéristique de la generation automatique de code permet de profiter de dispositifs avec un haut degré d'adaptabilité et de performances de traitement. Cette méthodologie basée sur HiLeS et SysML est axée sur l'étude des systems photovoltaïques partiellement ombragés ainsi que des architectures flexibles en électronique de puissance en raison de leur influence sur les microgrids actuels. En outre, cette perspective de recherche est utilisée pour évaluer les stratégies de contrôle et de supervision dans les conditions normales et de défauts. Ce travail représente la première étape pour développer une approche innovante en temps réel pour modéliser et émuler des systèmes photovoltaïques complexes en tenant compte des propriétés de modularité, de haut degré d'évolutivité et des conditions de travail non uniformes. Les résultats expérimentaux et analytiques valident la méthodologie proposéeNowadays, the integration of photovoltaic systems into electrical grids is encouraging the expansion of microgrids. However, this integration has also increased the power system complexity leading to new research challenges. Some of these research challenges require the development of innovative modeling approaches able to deal with this increasing complexity. Therefore, this thesis is intended to contribute with an innovative methodology component-based for modeling and emulating in real-time photovoltaic systems integrated to microgrids. The proposed modeling approach uses the Systems Modeling Language (SysML) to describe the structure and behavior of integrated photovoltaic systems. In addition, this study presents the High Level Specification of Embedded Systems (HiLeS) to transform automatically the developed SysML models in embedded code and Petri nets. These characteristics of automatic code generation and design based on Petri nets allow taking advantage of FPGAs for application of real-time emulation of photovoltaic systems. This dissertation is focused on partially shaded photovoltaic systems and flexible power electronics architectures because of their relevant influence on current microgrids. Furthermore, this research perspective is intended to evaluate control and supervision strategies in normal and fault conditions. This work represents the first step to develop an innovative real-time approach to model and emulate complex photovoltaic systems considering properties of modularity, high degree of scalability, and non-uniform working conditions. Finally, experimental and analytical results validate the proposed methodology
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Wen, Yuzhong. "Replication of Concurrent Applications in a Shared Memory Multikernel." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/71813.
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State Machine Replication (SMR) has become the de-facto methodology of building a replication based fault-tolerance system. Current SMR systems usually have multiple machines involved, each of the machines in the SMR system acts as the replica of others. However having multiple machines leads to more cost to the infrastructure, in both hardware cost and power consumption. For tolerating non-critical CPU and memory failure that will not crash the entire machine, there is no need to have extra machines to do the job.
As a result, intra-machine replication is a good fit for this scenario. However, current intra-machine replication approaches do not provide strong isolation among the replicas, which allows the faults to be propagated from one replica to another.
In order to provide an intra-machine replication technique with strong isolation, in this thesis we present a SMR system on a multi-kernel OS. We implemented a replication system that is capable of replicating concurrent applications on different kernel instances of a multi-kernel OS. Modern concurrent application can be deployed on our system with minimal code modification. Additionally, our system provides two different replication modes that allows the user to switch freely according to the application type.
With the evaluation of multiple real world applications, we show that those applications can be easily deployed on our system with 0 to 60 lines of code changes to the source code. From the performance perspective, our system only introduces 0.23\% to 63.39\% overhead compared to non-replicated execution.Master of Science
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Silva, Laudson Ferreira da. "Alterações fisiológicas de gramíneas tropicais submetidas a diferentes níveis de irradiância." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7201.
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This work aimed to analyze the growth and the partition of assimilates in plants such as Urochloa brizantha cv. Marandu, U. decumbens cv. Basilisk, Panicum maximum cv. Massai and Cynodon dactylon cv. Vaquero, submitted to three levels of luminosity (100, 50 and 25%). The plants were collected at regular intervals of seven days, from the 20th day after the emergency (DAE), to seventy six DAE, with a last collection of ninety DAE. The height (H), tiller number (TN), root dry matter (RDM), stem dry matter (SDM), leaf dry matter (LDM), leaf mass ratio (LMR), ratio between root dry matter and aerial part of the dry matter (RRAP), total dry matter (TDM), specific leaf area (SLA), leaf area ratio (LAR), liquid assimilation rate (LIAR), relative growth rate (RGR), leaf area index (LAI), crop growth rate (CGR), chlorophyll and carotenoids content. The analyzed species grew and developed in an environment with 50% of light equivalent to plants grown in full sun, since there were no significant differences regarding H, RDM, SDM, LDMC, TDM. Similarly, there was no significant difference in LIAR, RGR and CGR in the species, except in P. maximum, which presented such physiological indicators of growth higher than plants grown in the full sun. LAI was also equivalent, except for U. brizantha and U. decumbens, which presented higher index than plants in full sun. The luminosity level of 25% negatively affected the growth and development of the species, except in P. maximum, whose results were equivalent to those presented in full sun and 50% of light. Species demonstrate tolerance to light restriction and, therefore, production potential to be used in silvopasture and agrosilvopasture production systems.
O presente trabalho teve como objetivo analisar o crescimento e a partição de assimilados em plantas de Urochloa brizantha cv. Marandu, U. decumbens cv. Basilisk, Panicum maximum cv. Massai e Cynodon dactylon cv. Vaquero, submetidas a três níveis de luminosidade (100, 50 e 25%). As plantas foram coletadas em intervalos regulares de sete dias, a partir do vigésimo dia após a emergência (DAE), até setenta e seis DAE, sendo efetuada uma última coleta com noventa DAE. Avaliaram-se a altura (H), número de perfilhos (NP), matéria seca da raiz (MSR), matéria seca do colmo (MSC), matéria seca foliar (MSF), razão da massa foliar (RMF), razão entre a matéria seca radicular e a matéria seca da parte aérea (RRPA), matéria seca total (MST), área foliar específica (AFE), razão de área foliar (RAF), taxa assimilatória líquida (TAL), taxa de crescimento relativo (TCR), índice de área foliar (IAF), taxa de crescimento da cultura (TCC), teores de clorofilas e carotenoides. As espécies analisadas cresceram e desenvolveram-se em ambiente com 50% de luz de modo equivalente às plantas cultivadas em pleno sol, uma vez que não houve diferenças significativas quanto a H, MSR, MSC, MSF, MST. De modo similar, não houve diferença significativa na TAL, TCR e TCC nas espécies, exceto, em P. maximum, que apresentou tais indicadores fisiológicos do crescimento superiores às plantas cultivadas em pleno sol. O IAF foi igualmente equivalente, exceto, para U. brizantha e U. decumbens, que apresentou índice superior às plantas em pleno sol. O nível de luminosidade de 25% afetou negativamente o crescimento e desenvolvimento das espécies, exceto, em P. maximum, cujo resultado foi equivalente aos apresentados em pleno sol e 50% de luz. As espécies demonstram tolerância à restrição luminosa e, portanto, potencial de produção para serem utilizadas nos sistemas de produção silvipastoris e agrossilvipastoris.
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Clark, Benjamin J. Bevly David M. "GPS/INS operation in shadowed environments." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SUMMER/Mechanical_Engineering/Thesis/Clark_Benjamin_45.pdf.
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Gutekunst, Thomas F. "Shared window systems /." [S.l.] : [s.n.], 1995. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11120.
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Jacob, Jeremy. "On shared systems." Thesis, University of Oxford, 1987. http://ora.ox.ac.uk/objects/uuid:a17b30b9-eef5-4db2-8420-6df3cf3f8175.
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Most computing systems are shared between users of various kinds. This thesis treats such systems as mathematical objects, and investigates two of their properties: refinement and security. The first is the analysis of the conditions under which one shared system can be replaced by another, the second the determination of a measure of the information flow through a shared system. Under the heading of refinement we show what it means for one shared system to be a suitable replacement for another, both in an environment of co-operating users and in an environment of independent users. Both refine- ment relations are investigated, and a large example is given to demonstrate the relation for cooperating users. We show how to represent the security of a shared system as an 'inference function', and define several security properties in terms of such functions. A partial order is defined on systems, with the meaning 'at least as secure as'. We generalise inference functions to produce 'security specifications' which can be used to capture the desired degree of security in any shared system. We define what it means for a shared system to meet a security specification and indicate how implementations may be derived from their specifications in some cases. A summary of related work is given.
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Mairaj, Mir Jawad. "USES: Uniview's Shader Effect System." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-92841.
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This thesis work details the implementation of a generic shader effect system for Uniview (a proprietary 3D graphics software for the display of astronomical data in digital planetariums developed by SCISS AB). The system enables Uniview to load a variety of 3D file formats, customize them in various ways and, using a multipass setup, create complicated effects including rainbows, shadows, orbiting meteorites etc. The functionality is similar (though tailored to Uniview's need) to effect systems such as AMD's RenderMonkey or Nvidia's FX Composer.
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Straßer, Markus. "Programmgenerator für Shared Workspace-Objekte." [S.l. : s.n.], 1994. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB8862198.
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Malmer, Johan, and Niklas Seipel. "Shadow IT – Skuggsystem : En förklarande fallstudie om när verksamheten tar makten över IT." Thesis, Uppsala universitet, Institutionen för informatik och media, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-316062.
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Sådana system i en organisation som inte är sanktionerade kallas skuggsystem. I detta arbete har vi genomfört en fallstudie vid Försvarets materielverk FMV för att undersöka vad som orsakar att skuggsystem uppkommer. I studien har ett antal skuggsystem identifierats och möjliga orsaker har analyserats. Det är viktigt för en organisation att skaffa kunskap om skuggsystemens existens för att kunna hantera dem och därför är det viktigt med en förståelse för orsakerna bakom.Systems in an organization that are not formally sanctioned are called shadow systems. In this paper we have conducted a case study at the Swedish Defence Material Administration FMV to better understand the drivers behind the creation of shadow systems. The study has identified a number of shadow systems and possible drivers have been analyzed. It is important for an organization to gain knowledge about the existence of shadow systems in order to manage them. Therefore it is important to have an understanding of the drivers behind shadow systems.
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Prescher, Daniel. "Shared Service Center : Att införa ett Shared Service Center." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-22481.
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Wyatt, Douglas Karl. "Shared libraries in an exokernel operating system." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42736.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (p. 47).
by Douglas Karl Wyatt.
M.Eng.
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Schmidt, Brian W. (Brian William). "A Shared Memory System for Fresh Breeze." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/46508.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references (p. 54).
The Shared Memory System (SMS) for Fresh Breeze, a multiprocessor chip guided by modular programming principles, provides a global space from which all the fresh breeze processors access chunks of memory. The SMS supports the operations of: obtaining unique identifiers for new chunks; storing a chunk; accessing a chunk using its unique identifier; and incrementing or decrementing the reference count of a chunk. The SMS utilizes two levels of storage, a main storage component and many smaller clusters which connect to the Fresh Breeze processing chips. In this way the system attempts to achieve good performance at a low cost while remaining scalable to support many Fresh Breeze chips.
by Brian W. Schmidt.
M.Eng.
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Lopes, Paulo Orlando Reis Afonso. "A shared-disk parallel cluster file system." Doctoral thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/2082.
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Dissertação apresentada para obtenção do Grau de Doutor em Informática Pela Universidade Nova de Lisboa, Faculdade de Ciências e TecnologiaToday, clusters are the de facto cost effective platform both for high performance computing (HPC) as well as IT environments. HPC and IT are quite different environments and differences include, among others, their choices on file systems and storage: HPC favours parallel file systems geared towards maximum I/O bandwidth, but which are not fully POSIX-compliant and were devised to run on top of (fault prone) partitioned storage; conversely, IT data centres favour both external disk arrays (to provide highly available storage) and POSIX compliant file systems, (either general purpose or shared-disk cluster file systems, CFSs). These specialised file systems do perform very well in their target environments provided that applications do not require some lateral features, e.g., no file locking on parallel file systems, and no high performance writes over cluster-wide shared files on CFSs. In brief, we can say that none of the above approaches solves the problem of providing high levels of reliability and performance to both worlds. Our pCFS proposal makes a contribution to change this situation: the rationale is to take advantage on the best of both – the reliability of cluster file systems and the high performance of parallel file systems. We don’t claim to provide the absolute best of each, but we aim at full POSIX compliance, a rich feature set, and levels of reliability and performance good enough for broad usage – e.g., traditional as well as HPC applications, support of clustered DBMS engines that may run over regular files, and video streaming. pCFS’ main ideas include: · Cooperative caching, a technique that has been used in file systems for distributed disks but, as far as we know, was never used either in SAN based cluster file systems or in parallel file systems. As a result, pCFS may use all infrastructures (LAN and SAN) to move data. · Fine-grain locking, whereby processes running across distinct nodes may define nonoverlapping byte-range regions in a file (instead of the whole file) and access them in parallel, reading and writing over those regions at the infrastructure’s full speed (provided that no major metadata changes are required). A prototype was built on top of GFS (a Red Hat shared disk CFS): GFS’ kernel code was slightly modified, and two kernel modules and a user-level daemon were added. In the prototype, fine grain locking is fully implemented and a cluster-wide coherent cache is maintained through data (page fragments) movement over the LAN. Our benchmarks for non-overlapping writers over a single file shared among processes running on different nodes show that pCFS’ bandwidth is 2 times greater than NFS’ while being comparable to that of the Parallel Virtual File System (PVFS), both requiring about 10 times more CPU. And pCFS’ bandwidth also surpasses GFS’ (600 times for small record sizes, e.g., 4 KB, decreasing down to 2 times for large record sizes, e.g., 4 MB), at about the same CPU usage.
Lusitania, Companhia de Seguros S.A, Programa IBM Shared University Research (SUR)
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Zeidler, Dirk. "Coherent control of molecular dynamics with shaped femtosecond pulses." [S.l.] : [s.n.], 2001. http://edoc.ub.uni-muenchen.de/archive/00000236.
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Henke, Wiebke Lena. "Shared Mobility As A Socio-Technical System : An investigation of the mobility system in Augsburg." Thesis, Internationella Handelshögskolan, Jönköping University, IHH, Centre for Information Technology and Information Systems (CenITIS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49674.
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A major shift in our society is the one from a goods-dominant logic to a service-dominant one. Ownership becomes less important, while services from the area of sharing economy experience a rising demand. Municipalities and private companies are adapting and different shared mobility systems are emerging from their pursuit of new forms of mobility. In 2019, Augsburg created a shared mobility system where public transport, carsharing and bikesharing are all provided via one subscription. As this form of subscription does not have many customers yet, this thesis aims to first identify the system and research which reason and components motivate the people in Augsburg to use the system, as well as collecting different ideas for improvement. An expert interview was conducted with someone from the operator side and then customer interviews were held to get an insight from the customers’ point of view. This data was analyzed using tools from the area of information system as well as information architecture and the system was mapped out and discussed. The system was mapped out around the user and the connections were shown, which indicated that the user wants simplicity and clarity, as too many platforms and ways to book a mobility service was stated negatively.
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Lai, Sherman. "Shared displays to support collaborative exploration of ocean summits." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/711.
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In group decision support systems, understanding the roles, dynamics and relationships between participants is imperative to streamlining the decision-making process. This is especially true when decision makers have varying interests. Research has shown that decision-making processes amongst groups with varying interests will often reach bottlenecks with issues, such as unwillingness to share information, or a limited ability of the participants to share ideas at the same time. We explored this research territory of group decision-making by implementing collaboration software to support Ocean Summits, a new approach that uses real-time simulations as part of the decision-making process for stakeholders to explore fisheries management policies. The research reported in this thesis has three goals: (1) to better understand the decision-making process in fisheries management, (2) to build a prototype system to tackle the major issues in the decision-making process and (3) to determine the best way to share and display information critical to the stakeholders' decision-making process by exploring the use of shared screens and information in comparison to private displays. We discovered that the use of shared screens with shared information yielded the best results, as opposed to private screens with shared information or private screens with private information. It was observed that sharing information allowed participants to explore more alternative solutions.
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Chemla, Daniel, and Daniel Chemla. "Algorithms for optimizing shared mobility systems." Phd thesis, Université Paris-Est, 2012. http://pastel.archives-ouvertes.fr/pastel-00839521.
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Bikes sharing systems have known a growing success all over the world. Several attempts have been made since the 1960s. The latest developments in ICT have enabled the system to become efficient. People can obtain real-time information about the position of the vehicles. More than 200 cities have already introduced the system and this trend keeps on with the launching of the NYC system in spring 2013. A new avatar of these means of transportation has arrived with the introduction of Autolib in Paris end of 2011.The objective of this thesis is to propose algorithms that may help to improve this system efficiency. Indeed, operating these systems induces several issues, one of which is the regulation problem. Regulation should ensures users that a right number of vehicles are present at any station anytime in order to fulfill the demand for both vehicles and parking racks. This regulation is often executed thanks to trucks that are travelling the city. This regulation issue is crucial since empty and full stations increase users' dissatisfaction. Finding the optimal strategy for regulating a network appears to be a difficult question. This thesis is divided into two parts. The first one deals with the "static" case. In this part, users' impact on the network is neglected. This is the case at night or when the system is closed. The operator faces a given repartition of the vehicles. He wants the repartition to match a target one that is known a priori. The one-truck and multiple-truck balancing problems are addressed in this thesis. For each one, an algorithm is proposed and tested on several instances. To deal with the "dynamic" case in which users interact with the system, a simulator has been developed. It is used to compare several strategies and to monitor redistribution by using trucks. Strategies not using trucks, but incentive policies are also tested: regularly updated prices are attached to stations to deter users from parking their vehicle at specified stations. At last, the question to find the best initial inventory is also addressed. It corresponds to the case when no truck are used within the day. Two local searches are presented and both aim at minimizing the total time lost by users in the system. The results obtained can be used as inputs for the target repartitions used in the first part. During my thesis, I participated to two EURO-ROADEF challenges, the 2010 edition proposed by EDF and the 2012 one by Google. In both case, my team reached the final phase. In 2010, our method was ranked fourth over all the participants and led to the publication of an article. In 2012, we ranked eighteenth over all the participants. Both works are added in the appendix
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Beal, Jacob Stuart Michael. "Generating communication systems through shared context." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87194.
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Chemla, Daniel. "Algorithms for optimizing shared mobility systems." Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1066/document.
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Les systèmes de vélos en libre-service ont connu ces dernières années un développement sans précédent. Bien que les premières tentatives de mise en place remontent aux années 60, l'arrivée de technologies permettant un suivi des différents véhicules mis à la disposition du grand public et de l'état des bornes de stationnement en temps réel a rendu ces systèmes plus attractifs. Plus de 200 villes disposent de tels systèmes et cette tendance se poursuit avec l'entrée en fonctionnement du système de New York prévue pour mars 2013. La fin de l'année 2011 a été marquée par l'arrivée d'un nouvel avatar de ce type de transport avec la mise en place d'Autolib à Paris. L'objectif de cette thèse est de proposer des algorithmes d'aide à la décision pour l'optimisation de réseaux de transport en libre-service. L'exploitation de ces systèmes, qui fleurissent actuellement un peu partout dans le monde, pose en effet de nombreux problèmes, l'un des plus cruciaux étant celui de la régulation. Cette dernière a pour objectif de maintenir dans chaque station un nombre de vélos ni trop faible, ni trop élevé, afin de satisfaire au mieux la demande. Cette régulation se fait souvent par le biais de camions qui effectuent des tournées sur le réseau. Il apparaît rapidement que la question d'une régulation optimale à l'aide d'une flotte fixée de camions est une question difficile. La thèse est divisée en deux parties. Dans la première partie, le cas “statique” est considéré. Les déplacements de véhicules dus aux usagers sont négligés. Cela traduit la situation la nuit ou lorsque le système est fermé à la location. L'opérateur doit redistribuer les véhicules afin que ceux-ci soient disposés selon une répartition définie. Les problèmes de rééquilibrage avec un ou plusieurs camions sont traités. Pour chacun des deux cas, un algorithme est proposé et utilisé pour résoudre des instances de tailles variées. La seconde partie traite du cas “dynamique” dans lequel les utilisateurs interagissent avec le système. Afin d'étudier ce système complexe, un simulateur a été développé. Il est utilisé pour comparer différentes stratégies de redistribution des véhicules. Certaines utilisent des camions se déplaçant dans la ville pendant la journée. D'autres tentent d'organiser une régulation intrinsèque du système par le biais d'une politique d'incitation : des prix mis à jour régulièrement encouragent les usagers à rendre leur véhicule dans certaines stations. Enfin, si on choisit de ne pas utiliser de camion durant la journée, la question de la détermination du nombre optimal de véhicules à disposer à chaque station se pose. Deux méthodes de recherche locale visant à minimiser le temps total perdu par les usagers sont présentées. Les résultats obtenus peuvent servir pour la définition des répartitions cibles de la première partie. Durant ma thèse, j'ai pu participer à deux challenges EURO/ROADEF, celui de 2010 proposé par EDF et celui de 2012 proposé par Google. Dans les deux cas, mon équipe a atteint les phases finales. Lors de l'édition de 2010, notre méthode est arrivée quatrième et a donné lieu à une publication. En 2012, notre méthode est arrivée dix-huitième sur tous les participants. Les travaux menés dans ces cadres sont ajoutés en annexeBikes sharing systems have known a growing success all over the world. Several attempts have been made since the 1960s. The latest developments in ICT have enabled the system to become efficient. People can obtain real-time information about the position of the vehicles. More than 200 cities have already introduced the system and this trend keeps on with the launching of the NYC system in spring 2013. A new avatar of these means of transportation has arrived with the introduction of Autolib in Paris end of 2011.The objective of this thesis is to propose algorithms that may help to improve this system efficiency. Indeed, operating these systems induces several issues, one of which is the regulation problem. Regulation should ensures users that a right number of vehicles are present at any station anytime in order to fulfill the demand for both vehicles and parking racks. This regulation is often executed thanks to trucks that are travelling the city. This regulation issue is crucial since empty and full stations increase users' dissatisfaction. Finding the optimal strategy for regulating a network appears to be a difficult question. This thesis is divided into two parts. The first one deals with the “static” case. In this part, users' impact on the network is neglected. This is the case at night or when the system is closed. The operator faces a given repartition of the vehicles. He wants the repartition to match a target one that is known a priori. The one-truck and multiple-truck balancing problems are addressed in this thesis. For each one, an algorithm is proposed and tested on several instances. To deal with the “dynamic” case in which users interact with the system, a simulator has been developed. It is used to compare several strategies and to monitor redistribution by using trucks. Strategies not using trucks, but incentive policies are also tested: regularly updated prices are attached to stations to deter users from parking their vehicle at specified stations. At last, the question to find the best initial inventory is also addressed. It corresponds to the case when no truck are used within the day. Two local searches are presented and both aim at minimizing the total time lost by users in the system. The results obtained can be used as inputs for the target repartitions used in the first part. During my thesis, I participated to two EURO-ROADEF challenges, the 2010 edition proposed by EDF and the 2012 one by Google. In both case, my team reached the final phase. In 2010, our method was ranked fourth over all the participants and led to the publication of an article. In 2012, we ranked eighteenth over all the participants. Both works are added in the appendix
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Jiang, Jingjing. "Shared-control for systems with constraints." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/33381.
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In the thesis we solve the shared-control problem for three classes of systems: a class of linear mechanical systems, mobile robots and rear wheel drive cars, via full state feedback or output feedback while ensuring that all the state constraints on the closed-loop systems are satisfied. To design the feedback controller for a system with state constraints we firstly remove all the constraints by changing the coordinates through a logarithmic function. Then the back-stepping method is used to design the controller and a Lyapunov-like analysis is used to prove stability properties of the closed-loop system. The shared-control algorithm is based on a hysteresis switch which reduces oscillations when changing the control authority from the human operator to the feedback controller or vice-versa. Unlike other shared-control methods, formal properties of the closed-loop systems with the shared-control have been rigorously established. We start the design of the full state-feedback shared-controller with the assumption that the admissible Cartesian configuration set Pa of the system is a time-invariant convex set defined by a group of linear inequalities. Then the results are extended to the design of shared-controllers via output feedback. In the cases in which only output feedback is available, we can solve the problem by either developing an observer or 'remodeling' the system. Through system remodeling we are able to deal with any shape of the admissible configuration set Pa, even time-varying ones. Simulation results help to illustrate how the shared-controller works and show its effectiveness. The state of the closed-loop system with the shared-control never violates the constraints. Experiments done on a mobile robot also demonstrate that the shared-control algorithm works well in practice and meets all safety requirements. In addition, the experimental results match the simulation ones, indicating that the modeling approximations are reasonable and suitable.
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Enochsson, Arvid. "Tolkning och rendering av L-system med beräknings-shaders." Thesis, Högskolan i Skövde, Institutionen för informationsteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18762.
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I detta arbete utförs en jämförelse av exekveringstid för tolkning och rendering av Lindenmayersystem (L-system), utfört av samma algoritm på CPU’n (eng. central processingunit) och GPU’n (eng. graphics processing unit). Undersökningen fokuserar på exekveringstid och dess utveckling vid olika typer av L-system, längder samt upplösning. Algoritmen implementerades i spelmotorn Unity både på CPU’n via C# och på GPU’n medhjälp av beräknings-shaders. Experimenten bestod av två L-system. Ett med förgreningaroch ett utan. Båda L-systemen testades med olika upplösningar och längder, varpå exekveringstid avlästes. Experimentens resultat påvisar stor fördel hos CPU-lösningen gällande exekveringstid. Bristen på GPU-anpassad kod, exempelvis kod utan förgreningar och med bra minneshantering, leder till att GPU’n presterar sämre. Arbetet avslutas med förslag på vidareforskning. Förslagen innefattar utökad testning på olika hårdvara, en mer kontrollerad testmiljö samt implementering av algoritmen i faktisk spelproduktion.
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Faltemier, Timothy Collin. "A groupware interface to a shared file system." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1352.
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Current shared file systems (NFS and SAMBA) are based on the local area network
model. To these file systems, performance is the major issue. However, as the Internet
grows, so does the distance between users and the Local Area Network. With this
increase in distance, the latency increases as well. This creates a problem when multiple
users attempt to work in a shared environment. Traditionally, the only way to
collaborate over the Internet required the use of locks.
These requirements motivated the creation of the State Difference
Transformation algorithm that allows users non-blocking and unconstrained interaction
across the Internet on a tree based structure. Fine Grain Locking, on the other hand,
allows a user the ability to set a lock on a character or range of characters while using a
form of the transformation algorithm listed above. This thesis proposes an
implementation that integrates these two technologies as well as demonstrating the
effectiveness and flexibility of State Difference Transformation.
The implementation includes two applications that can be used to further
research in both the transformation and locking communities. The first application
allows users to create tests for SDT and Fine Grain Locking and verify the correctness of
the algorithms in any given situation. The second application then furthers this research
by creating a real-world groupware interface to a shared file system based on a clientserver
architecture. This implementation demonstrates the usability and robustness of
these algorithms in real world situations.
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Rakamarić, Zvonimir. "Modular verification of shared-memory concurrent system software." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/32572.
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Software is large, complex, and error-prone. According to the US National Institute of Standards and Technology, software bugs cost the US economy an estimated $60 billion each year. The trend in hardware design of switching to multi-core architectures makes software development even more complex. Cutting software development costs and ensuring higher reliability of software is of global interest and a grand challenge. This is especially true of the system software that is the foundation beneath all general-purpose application programs.
The verification of system software poses particular challenges: system software is typically written in a low-level programming language with dynamic memory allocation and pointer manipulation, and system software is also highly concurrent, with shared-memory communication being the main concurrent programming paradigm. Available verification tools usually perform poorly when dealing with the aforementioned challenges. This thesis addresses these problems by enabling precise and scalable verification of low-level, shared-memory, concurrent programs. The main contributions are about the interrelated concepts of memory, modularity, and concurrency.
First, because programs use huge amounts of memory, the memory is usually modeled very imprecisely in order to scale to big programs. This imprecise modeling renders most tools almost useless in the memory-intensive parts of code. This thesis describes a scalable, yet precise, memory model that offers on-demand precision only when necessary.
Second, modularity is the key to scalability, but it often comes with a price --- a user must manually provide module specifications, making the verification process more tedious. This thesis proposes a light-weight technique for automatically inferring an important family of specifications to make the verification process more automatic.
Third, the number of program behaviors explodes in the presence of concurrency, thereby greatly increasing the complexity of the verification task. This explosion is especially true of shared-memory concurrency. The thesis presents a static context-bounded analysis that combines a number of techniques to successfully solve this problem.
We have implemented the above contributions in the verification tools developed as a part of this thesis. We have applied the tools on real-life system software, and we are already finding critical, previously undiscovered bugs.
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Khoo, Tuo Sheng Joel. "A comparison between a photographic shade analysis system and conventional visual shade matching method." Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/1860.
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There are no previous studies validating the accuracy and repeatability of ClearMatch photographic shade analysis system. The purpose of this study was to compare the shade matches performed by a photographic shade analysis system (ClearMatch) with conventional visual shade matching method under simulated clinical conditions.
Three shade matching methods were used to match twelve shade tabs under simulated clinical conditions using a Vita Classical shade guide: conventional visual shade matching using 3 human raters (VM – Visual method), photographic shade analysis system (CM - ClearMatch) using two different ways of normalizing the image (CM-A2 and CM-ref respectively). Shade matching for all methods was completed at two separate sessions. The Kappa statistic was used to determine the intra-rater and inter-rater agreement. CIELAB values of the shade results were used to produce scatter plots as well as to calculate the color difference (delta E) between VM and CM groups.
There was no inter-rater agreement between VM and CM-A2 (k=0.000 and k=0.015 for the first and second sessions respectively) while VM and CM-ref showed weak agreement (k=0.244 and k=0.091 respectively). Intra-rater agreement was strong in all groups VM, CM-A2 and CM-ref (0.705, 0.803 and 0.681 respectively). CM-A2 had 2 (8.3%) shade matches with a delta E of less than 2.6 (clinically imperceptible), while CM-ref had 12 (50.0%) imperceptible matches. CM-A2 had an additional 16 (66.6%) shade matches with delta E of less than 5.5 (clinically acceptable), while CM-ref had 23 (95.8%) additional acceptable matches.
There was poor agreement in exact shade matches between conventional visual shade matching method and the photographic shade analysis system. The repeatability of the photographic shade analysis system was shown to be comparable to conventional visual shade matching. Using conventional shade matching as the gold standard, the capability of this photographic shade analysis system to accurately shade match has not been achieved.
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Hysing, Andreas Dreyer. "Parallel Seismic Inversion for Shared Memory Systems." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11795.
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In this thesis will explore how a scientific application forseismic inversion can take advantage of multi-core programming on x86 architecture. The thesis will focus on most effective domain divisions, communication patterns and multithreaded scalability. Performance comparison withthe original codes will be included, as well as an evaluation of thedevelopment effort required for implementing such techniques.
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Bruce, Craig Steven. "Performance optimization for distributed-shared-data systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ32819.pdf.
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Molka, Daniel. "Performance Analysis of Complex Shared Memory Systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-221729.
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Systems for high performance computing are getting increasingly complex. On the one hand, the number of processors is increasing. On the other hand, the individual processors are getting more and more powerful. In recent years, the latter is to a large extent achieved by increasing the number of cores per processor. Unfortunately, scientific applications often fail to fully utilize the available computational performance. Therefore, performance analysis tools that help to localize and fix performance problems are indispensable. Large scale systems for high performance computing typically consist of multiple compute nodes that are connected via network. Performance analysis tools that analyze performance problems that arise from using multiple nodes are readily available. However, the increasing number of cores per processor that can be observed within the last decade represents a major change in the node architecture. Therefore, this work concentrates on the analysis of the node performance.
The goal of this thesis is to improve the understanding of the achieved application performance on existing hardware. It can be observed that the scaling of parallel applications on multi-core processors differs significantly from the scaling on multiple processors. Therefore, the properties of shared resources in contemporary multi-core processors as well as remote accesses in multi-processor systems are investigated and their respective impact on the application performance is analyzed. As a first step, a comprehensive suite of highly optimized micro-benchmarks is developed. These benchmarks are able to determine the performance of memory accesses depending on the location and coherence state of the data. They are used to perform an in-depth analysis of the characteristics of memory accesses in contemporary multi-processor systems, which identifies potential bottlenecks. However, in order to localize performance problems, it also has to be determined to which extend the application performance is limited by certain resources.
Therefore, a methodology to derive metrics for the utilization of individual components in the memory hierarchy as well as waiting times caused by memory accesses is developed in the second step. The approach is based on hardware performance counters, which record the number of certain hardware events. The developed micro-benchmarks are used to selectively stress individual components, which can be used to identify the events that provide a reasonable assessment for the utilization of the respective component and the amount of time that is spent waiting for memory accesses to complete. Finally, the knowledge gained from this process is used to implement a visualization of memory related performance issues in existing performance analysis tools.
The results of the micro-benchmarks reveal that the increasing number of cores per processor and the usage of multiple processors per node leads to complex systems with vastly different performance characteristics of memory accesses depending on the location of the accessed data. Furthermore, it can be observed that the aggregated throughput of shared resources in multi-core processors does not necessarily scale linearly with the number of cores that access them concurrently, which limits the scalability of parallel applications. It is shown that the proposed methodology for the identification of meaningful hardware performance counters yields useful metrics for the localization of memory related performance limitations.
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Coe, Paul. "Simulation models of shared-memory multiprocessor systems." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/13437.
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Multiprocessors have often been thought of as the solution to today's every increasing computing needs; but they are expensive, complex and difficult to design. This thesis focusses on the development of multiprocessor simulations that would aid the design and evaluation of such systems. The thesis starts by outlining the various possibilities for multiprocessor design and discusses some of the more common problems that must be addressed. A selection of simulation environments and models that have been developed to study complex computer systems are then described. The major problem with these simulation systems is that they generally focus on a small area of multiprocessor systems design in order to produce fast simulations that generate results quickly; consequently they provide very little flexibility and room for exploration. The aim of this project was to design and implement a flexible multiprocessor model within the HASE simulation environment, enabling the designer to explore a large design space with a minimum of effort, focussing more on flexibility and less on simulation speed. A parameterised simulation model has been developed that presents the designer with many design options with which to experiment. The parameters allow simple alternatives to be explored, for example, different component speeds or bus widths, as well as more complicated features, for example, coherence protocols, synchronisation primitives and architecture configurations. The model was designed in a modular manner that allows new parameter values to be incorporated, as well as new implementations of the various entities. To support this new model, the HASE system was extended to provide better support for multiprocessor modelling.
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Zhang, Ping, and Andrew Dillon. "HCI and MIS: shared concerns (Editorial)." Elsevier, 2003. http://hdl.handle.net/10150/106118.
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The fields of HCI and MIS share many concerns but have traditionally not shared
literatures, theories and results. This special issue is a first attempt at bridging the disciplinary
divide. In this paper, the history of both fields is briefly outlined and reasons for the
independence of eachare examined. The criteria for paper inclusion are outlined and each
paper is briefly introduced.
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Kouzoupis, Antonios. "High performance shared state schedulers." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-196145.
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Large organizations and research institutes store a huge volume of data nowadays.In order to gain any valuable insights distributed processing frameworks over acluster of computers are needed. Apache Hadoop is the prominent framework fordistributed storage and data processing. At SICS Swedish ICT we are building Hops, a new distribution of Apache Hadoop relying on a distributed, highly available MySQL Cluster NDB to improve performance. Hops-YARN is the resource management framework of Hops which introduces distributed resource management, load balancing the tracking of resources in a cluster. In Hops-YARN we make heavy usage of the back-end database storing all the resource manager metadata and incoming RPCs to provide high fault tolerance and very short recovery time. This project aims in optimizing the mechanisms used for persisting metadata in NDB both in terms of transactional commit time but also in terms of pre-processing them. Under no condition should the in-memory RM state diverge from the state stored in NDB. With these goals in mind several solutions were examined that improved the performance of the system, making Hops-YARN comparable to Apache YARN with the extra benefits of high-fault tolerance and short recovery time. The solutions proposed in this thesis project enhance the pure commit time of a transaction to the MySQL Cluster and the pre-processing and parallelism of our Transaction Manager. The results indicate that the performance of Hops increased dramatically, utilizing more resources on a cluster with thousands of machines. Increasing the cluster utilization by a few percentages can save organizations a big amount of money.Nu för tiden lagrar stora organisationer och forskningsinstitutioner enorma mängder data.För att kunna utvinna någon värdefull information från dessa data behöver den bearbetasav ett kluster av datorer. När flera datorer gemensamt ska bearbeta data behöver de utgåfrån ett så kallat "distributed processing framework''. I dagsläget är Apache Hadoop detmest använda ramverket för distribuerad lagring och behandling av data. Detta examensarbeteär har genomförts vid SICS Swedish ICT där vi byggt Hops, en ny distribution avApache Hadoop som drivs av ett distribuerat MySQL Cluster NDB som erbjuder en hög tillgänglighet.Hops-YARN är Hops ramverk för resurshantering med distribuerade ResourceManagers som lastbalanserarderas ResourceTrackerService. I detta examensarbete använder vi Hops-Yarn på ett sätt där ``back-end''databasen flitigt används för att hantera ResourceManagerns metadata och inkommande RPC-anrop. Vårkonfiguration erbjuder en hög feltolerans och återställer sig mycket snabbt vidfelberäkningar. Vidare används NDB-klustrets Event API för att ResourceManager ska kunnakommunicera med den distribuerade ResourceTrackers. Detta projekt syftar till att optimera de mekanismer som används för ihållande metadatai NDB både i termer av transaktions begå tid men också i termer av pre-bearbeta dem medan samtidigt garantera enhetlighet i RM: s tillstånd. ResourceManagerns tillståndi RAM-minnet får under inga omständigheteravvika från det tillstånd som finns lagrat i NDB:n. Med dessa mål i åtanke undersöktes fleralösningar som förbättrar prestandan och därmed gör Hops-Yarn jämförbart med Apache YARN.De lösningar som föreslås i denna uppsats förbättrar “pure commit time” när en transaktiongörs i ett MySQL Cluster samt förbehandlingen och parallelismen i vår Transaction Manager.Resultaten tyder på att Hops prestanda ökade dramatiskt vilket ledde till ett effektivarenyttjande av tillgängliga resurser i ett kluster bestående av ett tusental datorer. Närnyttjandet av tillgänliga resurser i ett kluster förbättras med några få procent kanorganisationer spara mycket pengar.
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Snášelová, Martina. "Návrh informačního systému." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2019. http://www.nusl.cz/ntk/nusl-399961.
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The master’s thesis deals with the design of a suitable information system for the operation of the shared workshop of Temple of Creation s.r.o. The introductory part of the thesis contains the theoretical background, which forms the basis for the analytical part of the current state of the company and the solution itself. Implementation of the proposed information system will be one of the possibilities how to increase the availability of the services offered by the creative center, simplify the processes and ensure the smooth running of the company.
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張宏亮 and Wang-leung Benny Cheung. "Migrating-home protocol for software distributed shared-memory system." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31222377.
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Campbell, Thomas J. "Interaction through the Shared Windowed Digital World (SWDW) system." Thesis, University of Essex, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387826.
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Cheung, Wang-leung Benny. "Migrating-home protocol for software distributed shared-memory system /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22030116.
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Scialoja, Alain. "Skill-based shared manipulation control of eye-surgical system." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/5805/.
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Holman, Frank S. "Neural network based shaped neighborhoods : a design retrieval system /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/5852.
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Yanco, Holly A. (Holly Ann). "Shared user-computer control of a robotic wheelchair system." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/86614.
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Gupta, Sandeep K. (Sandeep Kumar). "Protocol optimizations for the CRL distributed shared memory system." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/41004.
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Adler, Joseph (Joseph Adam). "Implementing distributed shared memory on an extensible operating system." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42805.
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Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (p. 86-91).
by Joseph Adler.
S.B.and M.Eng.
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Holsapple, Stephen Alan. "DSM64: A DISTRIBUTED SHARED MEMORY SYSTEM IN USER-SPACE." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/725.
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This paper presents DSM64: a lazy release consistent software distributed shared memory (SDSM) system built entirely in user-space. The DSM64 system is capable of executing threaded applications implemented with pthreads on a cluster of networked machines without any modifications to the target application. The DSM64 system features a centralized memory manager [1] built atop Hoard [2, 3]: a fast, scalable, and memory-efficient allocator for shared-memory multiprocessors.
In my presentation, I present a SDSM system written in C++ for Linux operating systems. I discuss a straight-forward approach to implement SDSM systems in a Linux environment using system-provided tools and concepts avail- able entirely in user-space. I show that the SDSM system presented in this paper is capable of resolving page faults over a local area network in as little as 2 milliseconds.
In my analysis, I present the following. I compare the performance characteristics of a matrix multiplication benchmark using various memory coherency models. I demonstrate that matrix multiplication benchmark using a LRC model performs orders of magnitude quicker than the same application using a stricter coherency model. I show the effect of coherency model on memory access patterns and memory contention. I compare the effects of different locking strategies on execution speed and memory access patterns. Lastly, I provide a comparison of the DSM64 system to a non-networked version using a system-provided allocator.
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Sasaki, H., S. Takagi, M. Shikida, and K. Sato. "Projection Clutching System for Force Transmission System based on Tulip-shaped Electrostatic Clutch." IEEE, 2007. http://hdl.handle.net/2237/9435.
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Merali, Shamir. "Designing and implementing memory consistency models for shared-memory multiprocessors." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23922.
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The most commonly assumed memory consistency model for shared-memory multiprocessors is Sequential Consistency (SC), which is a straightforward extension of the sequential programming model, and is therefore simple to reason with. However, SC places severe restrictions on the use of high-performance hardware and compiler optimizations. In order to mitigate the performance limitations of SC, designers have proposed relaxed consistency models that retain the SC programming interface for a restricted class of programs, and at the same time allow more aggressive hardware implementations by relaxing restrictions on memory access ordering.In cache-based systems, the management of the cache is an important issue in the implementation of a consistency model, since the presence of multiple copies of the same location in multiple caches requires that these copies be managed in a way that does not violate the requirements of the consistency model. Aggressive cache management schemes can exploit looser constraints on event ordering by reducing consistency-related cache-coherence traffic.
Location Consistency (LC), a consistency model first presented in (GS93), was designed expressly to minimize the constraints on event ordering, in an attempt to improve performance. At the same time, LC presents a formally defined interface that is easy to understand and reason with. In this thesis, we present sufficiency conditions for LC, propose a cache coherence protocol that implements the model, and present a preliminary cost and performance analysis of the protocol.
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Krishnaswamy, Vijaykumar. "Shared state management for time-sensitive distributed applications." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/8197.
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Ramesh, Bharath. "Samhita: Virtual Shared Memory for Non-Cache-Coherent Systems." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/23687.
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Among the key challenges of computing today are the emergence of many-core architectures and the resulting need to effectively exploit explicit parallelism. Indeed, programmers are striving to exploit parallelism across virtually all platforms and application domains. The shared memory programming model effectively addresses the parallelism needs of mainstream computing (e.g., portable devices, laptops, desktop, servers), giving rise to a growing ecosystem of shared memory parallel techniques, tools, and design practices. However, to meet the extreme demands for processing and memory of critical problem domains, including scientific computation and data intensive computing, computing researchers continue to innovate in the high-end distributed memory architecture space to create cost-effective and scalable solutions. The emerging distributed memory architectures are both highly parallel and increasingly heterogeneous. As a result, they do not present the programmer with a cache-coherent view of shared memory, either across the entire system or even at the level of an individual node. Furthermore, it remains an open research question which programming model is best for the heterogeneous platforms that feature multiple traditional processors along with accelerators or co-processors. Hence, we have two contradicting trends. On the one hand, programming convenience and the presence of shared memory call for a shared memory programming model across the entire heterogeneous system. On the other hand, increasingly parallel and heterogeneous nodes lacking cache-coherent shared memory call for a message passing model. In this dissertation, we present the architecture of Samhita, a distributed shared memory (DSM) system that addresses the challenge of providing shared memory for non-cache-coherent systems. We define regional consistency (RegC), the memory consistency model implemented by Samhita. We present performance results for Samhita on several computational kernels and benchmarks, on both cluster supercomputers and heterogeneous systems. The results demonstrate the promising potential of Samhita and the RegC model, and include the largest scale evaluation by a significant margin for any DSM system reported to date.Ph. D.
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Echarres, Lesly María Mejía. "Introduction to the Shadow Banking System." Dissertação, Faculdade de Economia da Universidade do Porto, 2011. http://hdl.handle.net/10216/63683.
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Echarres, Lesly María Mejía. "Introduction to the Shadow Banking System." Master's thesis, Faculdade de Economia da Universidade do Porto, 2011. http://hdl.handle.net/10216/63683.
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Prytz, Erik. "Performance and Shared Understanding in Mixed C2-Systems." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-56430.
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OBJECTIVE: This thesis had two purposes. The main one was to examine how mixed conditions affect a Command & Control (C2) system, particularly in terms of shared understanding, situation awareness (SA), performance and workload. Mixed conditions refer here to when subsystems of a larger C2-system differ in terms of capabilities, particularly those capabilities influencing the understanding of a situation e.g. sensors or communication, which could affect the C2-capabilities when working toward a common goal. The second purpose of this thesis was to investigate a newly developed tool for measuring shared understanding, Shared Priorities, in terms of validity and usefulness. METHOD: A number of hypotheses were constructed and investigated by a controlled experiment using a microworld, C3Fire, where two-man teams fought a simulated forest fire. The independent variable manipulated was the type of support system used. One condition used one computer interface per participant, the second was mixed conditions where one participant used the computer interface and one used a paper map, and the last condition was both participants using a paper map. Different questionnaires developed to measure SA, workload etc. was used to measure the dependent variables. RESULTS: The statistical analysis performed on the collected data showed that the performance and SA was comparatively better when both participants used the computer interface than the mixed condition, which in turn was better than when both participants used a paper map. For workload and teamwork, no differences between the mixed condition and the dual map condition were found. As for the Shared Priorities measurement, no differences were found between any of the conditions. CONCLUSION: A C2-system in which some additional capabilities are introduced for some but not all subsystems may not benefit in some regards, e.g. workload and teamwork, but could improve in others, e.g. SA and performance. A Structural Equation Model (SEM) shows that the theoretical constructs of SA, workload, teamwork and performance are related and affect each other, so that the workload of the system negatively affects the teamwork and SA, while the teamwork may affect SA positively and a high SA enables high performance.
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Gong, Yan. "Locking granularity in shared-nothing parallel database systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ36879.pdf.
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Ruppert, Eric. "The consensus power of shared-memory distributed systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0028/NQ49848.pdf.
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Wahbe, Andrew A. "Linearizable shared objects for asynchronous message passing systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0024/MQ50378.pdf.
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