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1
Fontana, Serenella <1992>. "Beijing Consensus: nuovo modello di sviluppo alternativo al Washington Consensus?" Master's Degree Thesis, Università Ca' Foscari Venezia, 2017. http://hdl.handle.net/10579/11946.
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Questa tesi nasce dall’esigenza di analizzare l’esistenza di un modello di sviluppo economico e sociale alternativo a quello promosso dalle potenze occidentali dalla fine della Guerra Fredda ad oggi; per fare ciò evidenzieremo le caratteristiche dell'ortodossia americana del Washington Consensus, ne analizzeremo le critiche e ne studieremo punti forti e debolezze.
Ugual analisi sarà portata avanti per il possibile nuovo modello di sviluppo: il Beijing Consensus. Dopo avere sottolineato le sostanziali caratteristiche, le principali critiche ed avere indagato l’esistenza di questo nuovo modello la nostra analisi cercherà di mettere in relazione inizialmente le critiche.
Successivamente ci impegniamo a prendere in esame in modo dettagliato la reale contrapposizione tra il Beijing Consensus e il Washington Consensus. L’analisi delle similitudini e soprattutto delle differenze tra questi due consensi sarà utile al nostro scopo di affermare con più sicurezza e tranquillità l'esistenza di un nuovo e forte modello di sviluppo alternativo a quello statunitense che pone il dubbio sul futuro dell'egemonia americana.
2
Dormaar, Jacobus Marius Maarten. "Consensus in psychotherapy." Maastricht : Maastricht : Datawyse ; University Library, Maastricht University [Host], 1990. http://arno.unimaas.nl/show.cgi?fid=5561.
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van, de Hoef Sebastian. "Extended Consensus Algorithms." Thesis, KTH, Reglerteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-125809.
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An extension of the linear consensus protocol for agents moving in the plane is considered. For single integrator agents the use of a vector perpendicular to the standard consensus feedback leads to a large family of trajectories. If the new perpendicular term is applied only sustained oscillations are facilitated. For special congurations the form of the system trajectories is given in form of eigenvalues and {vectors of the system matrix. A proof is given that this additional term does not eect stability. On the other hand it is motivated that robustness against discrete implementation and switching topologies can be decreased. The control strategy is also applied to agents with double integrator dynamics. Stability can be archived with suciently high velocity feedback and the eect of this feedback on the system performance is further discussed. Using the results for single integrators a self{triggered consensus control strategy is proposed based on the assumption of bounded input magnitude of the other agents. Additional communication of the actual input leads to asymptotic convergence. By applying similar reasoning it is shown how local controllers at the agents can avoid circular regions in state{space while moving towards consensus.
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Bloom, Dorian L. "Morality by Consensus." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1426927930.
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Guerrazzi, Stella <1987>. "Dal Washington Consensus al Beijing Consensus: l'Iran come caso di studio." Master's Degree Thesis, Università Ca' Foscari Venezia, 2013. http://hdl.handle.net/10579/2910.
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Il mio studio ruota intorno ad un nuovo modello di sviluppo alternativo al Washington Consensus, il così detto Beijing Consensus, termine in evoluzione che descrive un modello alternativo di riferimento per i paesi cosiddetti in via di sviluppo. Si tratta quindi di fornire una visione di come l’asse di un modello economico di riferimento si stia spostando dagli Stati Uniti fino alla Cina.
Utilizzando come studio empirico le relazioni che si interpongono tra un paese del Medio Oriente e la Cina si cercherà di capire la validità o meno della tesi stessa. La scelta di utilizzare l’Iran come caso di studio risulta significativo, in quanto paese simbolo del Medio Oriente e storicamente importante per quanto riguarda il mercato energetico. In prima analisi cercherò di delineare gli incentivi che hanno spinto due paesi così ideologicamente diversi a imbastire una relazione concentrando il mio interesse sul contesto del declino del potere USA in Medio Oriente. Successivamente analizzando il mercato energico porrò l'attenzione sul peso che gli interessi economici hanno avuto e hanno tutt’ora nel facilitare queste relazioni. Infine, osservando le relazioni che Cina e Iran hanno con gli USA, si cercherà di vedere quali possono essere i possibili limiti alle loro politiche.
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Padmanabhan, Sudarsan. "Two models of consensus." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001113.
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Monsen, Mats. "Overlapping Consensus in Malaysia." Thesis, Linköping University, Centre for Applied Ethics, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-9214.
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<p>An empirical study of how Malaysian pluralism is understood through Islam Hadhari, Article 11 and the Inter-faith Commission against the backdrop of current Malaysian political and social history, coupled with a theoretical analysis through John Rawls' Political Liberalism, with particular emphasis on the idea of Overlapping Consensus.</p><p>The thesis is an attempt at applying Rawls' theory on the practical case of Malaysia, as a plural society, while at the same time using the practical case of Malaysia to highlight parts of Rawls' own theory.</p>
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Seuret, Alexandre, Dimos V. Dimarogonas, and Karl Henrik Johansson. "Consensus under communication delays." KTH, Reglerteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-28520.
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This paper deals with the consensus problem under communication network inducing delays. It is well-known that introducing a delay leads in general to a reduction of the performance or to instability due to the fact that timedelay systems are infinite dimensional. For instance, the set of initial conditions of a time-delay system is not a vector but a function taken in an interval. Therefore, investigating the effect of time-delays in the consensus problem is an important issue. In the present paper, we assume that each agent receives instantaneously its own state information but receives the state information from its neighbors after a constant delay. Two stability criteria are provided based on the frequency approach and on Lyapunov-Krasovskii techniques given in terms of LMI. An analytic expression of the consensus equilibrium which depends on the delay and on the initial conditions taken in an interval is derived. The efficiency of the method is tested for different network communication schemes.<br><p>QC 20110120</p>
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Ren, Ling Ph D. Massachusetts Institute of Technology. "Efficient and egalitarian consensus." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120372.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2018.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (pages 101-111).<br>Consensus is a classic problem in distributed computing. Research on consensus has traditionally focused on the permissioned setting where participants are fixed and know each other beforehand. Recently, the digital currency Bitcoin has popularized a new line of research on consensus in a permissionless environment, where participants may join or leave at any time and need not know how many other participants exist or who they are. Bitcoin's solution, now known as the Nakamoto consensus, is to build a proof-of-work chain and treat the longest proof-of-work chain as consensus decisions. However, this elegant solution does have limitations. First, it has long latency: under current parameters, it can take hours for a Bitcoin transaction to go through. Second, its use of hash-based proof-of-work has raised concerns about fairness and energy consumption. This thesis presents distributed algorithms and cryptographic primitives to address these limitations. I will first describe Solida, a permissionless consensus protocol with low latency. It has been observed that traditional Byzantine consensus protocols have much lower latency than Nakamoto consensus. Following this observation, Solida adapts traditional Byzantine consensus protocols from the permissioned setting to the permissionless setting by combining them with proof-of-work. I also design improved protocols for permissioned synchronous Byzantine consensus. I then turn to potential replacements for hash-based proof-of-work. I construct a proof-of-space protocol with tight security bounds as an energy-efficient alternative. Finally, I revisit the concept of memory-hard functions, the standard approach to improve fairness in proof-of-work. I argue that the memory-hardness approach overlooks energy efficiency fairness and suggest bandwidth-hard functions as egalitarian alternatives.<br>by Ling Ren.<br>Ph. D.
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Antus, Joakim. "Reaching Consensus Using Raft." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-301332.
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This thesis project implements and evaluates log replication using the Raft consensus algorithm. Raft presents a new and easier to understand consensus protocol for log replication in a distributed system. This thesis aims to evaluate the correctness and robustness of Raft by implementing a scalable system that is easy to maintain and test for further development. This thesis gives an in-depth description of Raft as well as a detailed explanation of the implemented system together with an evaluation of the system performance with focus on correctness.
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Babaee, Arta. "Distributed consensus in networks." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/12680.
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Distributed algorithms have gained a lot of attention during recent years. Their application in industry, particularly in wireless sensor networks has motivated researchers to try to design them in order to be less resource-consuming (e.g. memory and power), faster, and more reliable. There have been numerous distributed algorithms for different types of problems in the context of distributed algorithms. We are interested in a fundamental coordination problem namely the majority consensus problem. In the majority consensus problem nodes try to find the opinion of the majority in a network of interest. As our first contribution and motivated by the distributed binary consensus problem in [1] we propose a distributed algorithm for multivalued consensus in complete graphs. As our second contribution we propose an algorithm for the optimization of the binary interval consensus algorithm pioneered by Ben ezit et al in [2]. Finally we use binary interval consensus algorithm to design a framework for error-free consensus in dynamic networks using which nodes can leave or join the network during or after the consensus process.
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Gu, Yuhua. "Ant clustering with consensus." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0002959.
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Borghi, Giacomo. "Consensus-Based Optimization on Hypersurfaces." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21783/.
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In questo elaborato viene presentato un algoritmo Consensus-Based per l'ottimizazione vincolata a ipersuperfici. Il metodo consiste in una tecnica di ottimizzazione di tipo metaeuristico dove un insieme di particelle interagenti si muove secondo un meccanismo che unisce movimenti deterministici e stocastici per creare un consenso attorno ad un luogo del dominio dove è presente un minimo della funzione. La dinamica è governata da un sistema di SDE ed è studiata attraverso il formalismo della teoria cinetica per modelli di particelle interagenti. Innanzitutto, viene dimostrato che il sistema è ben posto e viene formalmente derivato il suo limite di campo medio. Il meccanismo di consenso viene poi studiato analiticamente e computazionalmente soffermandosi sulle difficoltà che il rispetto del vincolo comporta. Infine, vengono condotti esperimenti su classiche funzioni test.
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Pellett, Andrew. "The Extended Kalman-Consensus Filter." Fogler Library, University of Maine, 2011. http://www.library.umaine.edu/theses/pdf/PellettA2011.pdf.
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Ménager, Lucie. "Communication, connaissance commune et consensus." Phd thesis, Université Panthéon-Sorbonne - Paris I, 2006. http://tel.archives-ouvertes.fr/tel-00174147.
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Cette thèse vise à dégager l'unité des travaux sur la connaissance commune, réalisés à la suite de l'article fondateur d'Aumann ("Agreeing to Disagree ", 1976). Elle se compose de six chapitres. Les deux premiers présentent la modélisation de la connaissance utilisée, ainsi que les résultats de la littérature. Les trois suivants sont des contributions originales à la littérature. Le dernier compare les propriétés des conditions introduites dans les chapitres 3 et 4 avec les conditions de la littérature. Dans le chapitre 3, on généralise le résultat d'Aumann et de Cave [1976] et Bacharach [1985] au cas où la connaissance commune porte sur une statistique des décisions individuelles. On montre que si les règles de décisions suivies par les agents sont stables par l'union équilibrée, et si la statistique est exhaustive, alors la connaissance commune d'une statistique des décisions individuelles implique le consensus. Dans le chapitre 4, on étudie les conditions sous lesquelles la communication des décisions individuelles peut mener au consensus. On montre que des conditions suffisantes sont que le protocole de communication soit équitable, et que les agents communiquent leur action optimale, c'est-à-dire l'action qui maximise leur espérance d'utilité. Le chapitre 5 part du constat que différents protocoles de communication conduisent à des issues différentes, en termes de consensus et de montant d'information apprise par les agents pendant le processus. On montre que s'il est connaissance commune parmi des agents que certains d'entre eux sont en désaccord à propos du protocole à utiliser, alors le consensus est le même quel que soit le protocole.
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Devici, Dogukan. "Consensus performance in sensor networks." Thesis, KTH, Kommunikationsnät, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-132186.
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Mårtensson, Christopher, and Linus Sjövall. "Consensus Algorithms - Flocking and Swarms." Thesis, KTH, Optimeringslära och systemteori, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105773.
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An interesting eld of mathematics is the study of swarming and ocking. By using graph theory, one can describe a system of agents that transfer information between each other. With the help of certain algorithms it is possible to update the agent's information in order to reach consensus between the agents. If the information relates to the position, the velocity, or the acceleration of each agent, a behaviour similar to that of animals ocks or insect swarms is observed. Several other applications also exist, for example in systems of multiple robots when no central coordination is possible or simply not desired. In this paper dierent algorithms used to change the agent's information state will be studied and researched in order to determine the requirements under which the entire set of agents achieve consensus. First the case where agents receive information from a non-changing set of agents will be studied. Specically a particular algorithm, where each agent's information is determined by a linear function depending on the information state of all other agents from which information is received, will be considered. A requirement for this particular algorithm to reach consensus is that every agent both receives information and also sends information to every other agent, directly or indirectly through other agents. If all information transfers are weighed equally, the consensus achieved will be the average of all initial information states. Consensus can also be reached under looser conditions where there exists an agent that sends information to every other agent, directly or indirectly. The changes of the system's behaviour when one uses dierent consensus algorithms will be discussed, and computer simulations of these will be provided. An interesting case is where the information (often referring to location, velocity or acceleration) is received only from agents within a given distance and thus the information is received from dierent agents at dierent times. This results in nonlinear algorithms and mostly simulations and interpretations will be given. An observation is that whether consensus is achieved or not depends partially on the initial information states of the agents and the maximum distance for information transfer.<br>Ett intressant omrade inom matematiken ar att beskriva fenomenet med ockar och svarmar. Med hjalp av grafteori kan man beskriva ett system av agenter som skickar information mellan varandra och med hjalp av algoritmer som beskriver hur varje agents informationen ska uppdateras sa att konsensus nas. Om informationen beskriver en position eller foryttning i rummet kan man observera ett beteende som liknar det hos djurockar eller insektssv armar. Manga andra tillampningsomraden nns ocksa, till exempel i system av robotar nar det saknas central styrning och internt beslutstagande ar onskvart. I denna rapport kommer olika algoritmer for att uppdatera en agents status att undersokas for att bestamma vilka krav som nns for att konsensus skall nas. Forsta delen kommer att behandla ett enklare fall dar varje agent tar emot information fran en oforanderlig uppsattning agenter. Specikt sa kommer en algoritm, dar en agents status bestams av en linjar funktion som beror pa statusen hos de agenter fran vilka information mottages, att studeras. Ett krav for att denna algoritm ska na konsensus ar att varje agent bade skickar och tar emot information fran samtliga ovriga agenter, direkt eller indirekt via andra agenter. Om alla informations overforingar vags lika sa kommer alla agenter na medelvardet av agenternas initialvarden. Konsensus kan ocksa nas under mindre restriktiva villkor, om det nns en agent som skickar information till alla andra noder (direkt eller indirekt). Forandringar av systemets beteende vid olika uppdateringsalgoritmer kommer att studeras och datorsimuleringar av dessa fenomen kommer att ges. Ett intressant fall ar da informationen (ofta position, hastighet eller acceleration) endast kan tas emot fran de agenter som nns inom ett givet avstand. darmed forandras den uppsattning agenter med vilka information overfors med tiden. Detta resulterar i olinjara algoritmer och framforallt kommer simulationer och tolkningar av dessa att ges. En observation ar att om konsensus nas eller inte beror starkt pa densiteten bland agenterna i utgangslaget samt det maximala avstand vid vilket informationsoverforing kan ske.
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Benedetto, Giacomo Giorgio Edward. "Institutionalised consensus in Europe's parliament." Thesis, London School of Economics and Political Science (University of London), 2005. http://etheses.lse.ac.uk/848/.
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Embedded consensus has characterised the behaviour of the European Parliament since its foundation in the 1950s. This research tests the path dependence of consensus during the period of 1994 to 2002, in the light of the changing institutional powers of the Parliament. It challenges existing theory and empirical evidence drawn mainly from roll call votes that has concluded that the European Parliament has become more competitive internally in response to increased institutional powers. There are three causal factors that reinforce consensus: the need to reconcile national and ideological divisions within a multinational political system; the pull of external institutional factors such as institutional change or the separation of powers; and internal incentives for collusion between political actors influenced by the need to accommodate the interests of the national elites present at the level of the European Union. Switzerland, a multiple cleavage system of decentralised federalism that includes consociational characteristics and a separation of powers, provides a comparative reference point for institutionalised consensus. The hypotheses of institutionalised consensus are tested empirically in four ways: 1) by roll call votes between 1994 and 2001, focusing on procedure, policy area, and the cut-off point of the 1999 elections; 2) competition and consensus in the distribution of policy-related office in the Parliament; 3) by Parliament’s use of its powers of appointment and censure over other institutions; and 4) by the internal consensus on the preparation of Parliament’s bids for greater powers when the European Union Treaties are reformed. In adapting the theory of path dependence to a multinational legislature, the methodology presented in this thesis can be applied in furthering the understanding of other comparable institutions.
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Mazhar, Othmane. "Optimal consensus and opinion dynamics." Thesis, KTH, Optimeringslära och systemteori, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-193656.
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In the following thesis we study the influence of the communication graph on the behavior of multi-agent systems. Specifically we investigate two issues the first is concerned with the existence of consensus control for linear dynamics, the second is a study of the behavior of a nonlinear dynamical related to opinion dynamics. For the finite optimal consensus problem of multi-agent system, we formulate the problem as an optimization problem on a Hilbert space to model the graph neighborhood constraints. Then we show that completeness of the graph is a necessary and sufficient condition of the existence of a finite time linear control that guarantees consensus in finite time. As a extension of this result we show that the optimal control we get is also optimal among the larger class of non linear control, and that it can be implemented as optimal for connected but not complete graphs if we replace the neighborhood restriction by a feedback control using the information of all edges of the graph. The second part is a study of a modified version of continuous opinion dynamic model by introduced Hegselmann an Krause. To modify the model we introduce stubborn agents; agent whose opinion do not change over time, specifically we introduce two types of agents: one that can influence the whole distribution at ones and we call it of positive influence and the other with a bounded influence and we call it of non negative influence. For each type introduced we study the topological properties of the distribution and the clustering phenomena observed but also the statistical properties and we do so in the presence of one or two stubborn agent. We finally end this part by two possible applications of the use of stubborn agents for reaching consensus or tracking trajectories.<br>I denna avhandling studerar vi inflytandet av kommunikationsgrafens beteende hos multi agent system. Vi undersöker särskilt två frågor, den första handlar om existensen av consensus styrlag för linjär dynamik och den andra studerar beteendet hos ickelinjär dynamik relaterad till opinionsdynamik. För det ändliga optimala konsensus problemet hos multi agent system formuleras det som ett optimeringsproblem i ett Hilbert rum för att modellera grafens grannvillkor. Vi visar att kompletthet hos grafen är ett nödvändigt och tillräckligt villkor för existens av en ändlig linjärtidsstyrlag som garanterar konsensus i ändlig tid. Som en utvidgning av detta resultat visar vi att den optimala styrlagen även är optimal i en större klass av ickelinjär reglering och att den kan implementeras som optimal för slutna men ej kompletta grafer om vi ersätter grannvillkoren med en återkopplande styrlag genom att använda informationen hos all kanter i grafen. Den andra delen av denna studie är en modifierad version av den kontinuerliga åsiktsdynamikmodellen som introducerades av Hegselmann och Krause. För att modifiera modellen introducerade vi envisa agenter, agenter varsåsikter ej ändrar över tiden, mer specifikt, vi introducerar två typer av agenter, en som kan påverka hela fördelningen på en gång och vi kallar detta positiv influens and den andra har ett begränsat inflytande och vi kallar denna icke negative influens. För varje introducerad typ studerar vi de topologiska egenskaperna av fördelningen och klustringsfenomen observerades men även de statisitiska egenskaperna och vi gjorde detta vid närvaro av en eller två envisa agenter. Vi avslutade denna del med två möjliga applikationer av envisa agenter för att nå consensus eller följa banor.
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Parvez, Imtiaz. "Data Transmission in Quantized Consensus." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc271874/.
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In the world of networked system, average consensus is an important dimension of co-ordinate control and cooperation. Since the communication medium is digital, real value cannot be transmitted and we need to perform quantization before data transmission. But for the quantization, error is introduced in exact value and initial average is lost. Based on this limitation, my 16 bit quantization method (sending MSB in 1-4 cycle and MSB+LSB in 5th cycle) reduces error significantly and preserves initial average. Besides, it works on all types of graphs (star, complete, ring, random geometric graph). My other algorithm, distributing averaging algorithm (PQDA) with probabilistic quantization also works on random geometric graph, star, ring and slow co-herency graph. It shows significant reduced error and attain strict consensus.
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Anselm, Robin Lee. "Consensus in Anesthesia Handoff Reporting." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3929.
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Despite some improvement, no consensus exists to perfect quality in anesthesia handoff practice and policy. This quality improvement project was designed to assist a local anesthesia and perioperative workforce questioning the quality of its current handoff. Theories and models used to inform the project included the Inter-Professional Team Collaborative, Lewin's change theory, the continuous quality improvement theory, and the knowledge to action model. The communication assessment tool (CAT) functioned as a needs assessment yielding a gap in handoff practice of 25 participants. The CAT also served as the post project evaluation survey. The situation, background, assessment, and recommendation (SBAR) tool was preferred. Participants received SBAR education, and clinical evaluation experience (CEX) survey training. The CEX described the quality indicators of participant handovers during four consecutive weeks. Descriptive and inferential statistics used to analyze data collections included means and standard deviations, examining trends in the continuous level variables. Reliability of the CAT variables was evaluated through Cronbach's alpha test of internal consistency. Inferential analyses included independent sample t tests, Pearson correlations, and analyses of variance (ANOVAs). Statistical significance was evaluated at the conventional level, α = .05. The use of the SBAR handoff tool showed parity in communication competency. Quality indicators of overall handoff remained highly satisfactory. Recommendations include the consensual use of SBAR handoff and competency evaluation across the anesthesia community. Modification of handoff practices and policies will enable social change by promoting quality indicators in anesthesia collaborative communication.
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Chamsi, Mohamed Zied. "Consensus et démocratie en Tunisie." Electronic Thesis or Diss., Université Côte d'Azur, 2023. http://www.theses.fr/2023COAZ0028.
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Au sein du paysage dévasté de ce que l'on a rapidement qualifié de "Printemps arabe", marqué par le rétablissement de l'autoritarisme en Égypte ainsi que par les guerres civiles en Libye, au Yémen et en Syrie, qui ont ravivé les groupes djihadistes et réveillé les conflits tribaux, ethniques et confessionnels, la Tunisie demeure une exception. Cette nation a certes traversé une transition politique longue et fragile, mais elle a réussi à préserver ses institutions républicaines, à élaborer une nouvelle Constitution saluée par de nombreux observateurs comme étant la plus progressiste du monde arabe, et à surmonter avec succès les élections législatives et présidentielles de 2014 et 2019.Cette exception tunisienne est le fruit de plusieurs facteurs, le principal étant le consensus, ou "Tawâfuq" en arabe. Le concept de "consensus" est la pierre angulaire de cette transition démocratique tunisienne, souvent qualifiée de transition consensuelle. La reconnaissance du Quartet du Dialogue national en Tunisie par le prix Nobel de la paix en 2014 illustre de manière emblématique ce consensus au cours de cette période de transition.De plus, le consensus a été au cœur de la Constitution tunisienne du 27 janvier 2014, caractérisée comme une Constitution consensuelle. Les différentes versions de la Constitution ont fait l'objet de débats et un consensus a été atteint. Ce processus a été hautement consultatif, visant à surmonter les divergences sur des questions cruciales afin d'obtenir un large accord au sein de la société tunisienne concernant les dispositions de la nouvelle Constitution. La création de la "commission des consensus" au sein de l'Assemblée nationale constituante visait à modifier les règles de représentation des différentes forces politiques. Cette commission n'a pas suivi une répartition proportionnelle, mais chaque groupe y était représenté par un nombre équivalent de députés.Cependant, bien que le consensus ait contribué à établir un régime politique et constitutionnel démocratique, faisant de la Tunisie une exception dans la région, il a également présenté certains effets pervers lors de la consolidation du régime, tant sur le plan politique qu'institutionnel et constitutionnel. En effet, l'esprit de conciliation, bien que tempérant les antagonismes et les divergences, n'a pas résolu les problèmes socio-économiques sous-jacents, et ceux-ci risquent de ressurgir après une période de latence<br>In a landscape devastated by what has been hastily labeled the "Arab Spring," marked by the resurgence of authoritarianism in Egypt and civil wars in Libya, Yemen, and Syria - which have reinvigorated jihadist groups and stirred the specters of tribalism, ethnic strife, and religious conflicts - Tunisia stands as a remarkable exception. Despite enduring a protracted and fragile political transition, the country has managed to safeguard its republican institutions, adopt a new Constitution acclaimed by numerous observers as the most progressive in the Arab world, and successfully navigate the challenges of two legislative and presidential elections in 2014 and 2019.This Tunisian exceptionalism can be attributed to several factors, with consensus (Tawâfuq) being paramount among them. Indeed, what we refer to as "consensus" constitutes the cornerstone of Tunisia's democratic transition, often characterized as consensual. The crowning achievement of this consensus during the transitional phase was the Nobel Peace Prize awarded to the quartet that orchestrated the national dialogue in Tunisia in 2014.Similarly, consensus lent its name to the Tunisian Constitution of January 27, 2014, acclaimed as a consensual Constitution. Successive versions of the Constitution underwent extensive deliberation, culminating in a consensus. This process was highly consultative, designed to reconcile differences on pivotal issues and secure broad societal agreement on the provisions of the new Constitution. Notably, the creation of the "consensus commission" within the National Constituent Assembly aimed to overhaul the rules governing the representation of various political forces. The composition of the consensus commission did not adhere to proportional representation; rather, each group was allotted an equivalent number of members.Nevertheless, while consensus facilitated the establishment of a democratic political and constitutional regime, setting Tunisia apart as an exception in the region, it also revealed certain adverse effects during the consolidation phase of the regime, encompassing political, institutional, and constitutional aspects. The spirit of reconciliation, which temporarily quelled antagonisms and differences, did not resolve underlying socio-economic issues, and these problems may resurface after a period of dormancy
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Torres, Stöckl Cynthia María, and Zubieta Elena Mercedes. "Consensus and divergence in the social representations of political leadership." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/99871.
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The aim of this paper is to analyze descriptively the consensual and differential dimensions of political leadership social representations, based on a convenience sample composed of Psychology, Philosophy and Humanities college students from Tucumán National University, Argentina. Results show a representational universe in tension characterized by opposite nuclear components: Leadership and Representation versus Power and Corruption, as well as opposite dimensions: Features / Positive Political Aspects versus Features / Negative Political Aspects, as well as two relevant clusters consistent with the latter two. Differences are also observed when analyzing variables such as: year in college, student’s political group membership, university political involvement and background / types of political figures.<br>Se analiza descriptivamente la faceta consensual y diferencial de las representaciones socialessobre la dirigencia política, en base a una muestra de estudiantes de la Facultad de Psicología y en la Facultad de Filosofía y Letras de la Universidad Nacional de Tucumán (UNT)-Argentina. Los resultados muestran un universo representacional en tensión caracterizado por componentes nucleares contrarios: Liderazgo y Representación versus Poder y Corrupción; y por dimensiones opuestas: Características/Aspectos Políticos Positivos versus Características/Aspectos Políticos Negativos, así como por conglomerados primordiales concordantes con estas últimas. Se observan también diferencias en función de variables como año de cursado, militancia en agrupaciones políticas estudiantiles, antecedentes de participación política en la Universidad y cargos/figuras políticas de diversa índole.
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Mutlu, Inan. "From Washington Consensus To Global Crisis." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612519/index.pdf.
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This thesis focuses on the changing modes of state intervention into the economy in neoliberalism. It contends that the so called free market is neither a natural process nor an inevitable result of the harmony of interest, but the result of a deliberate political making process. The global economic crisis provided ample evidence to refute the claim that state and market are separately existing and antagonistic entities and indicates that the issue is not the market or the state, since the state in a capitalist society is equally subordinate to capital, simply providing an alternative mode of regulation of capital accumulation. The state has always been essential for "<br>proper"<br>workings of the market, especially for the interests of capital and the neoliberal state is not an exception
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Barbaro, Josie. "Bob Hawke : riding the consensus wave /." Title page and contents only, 1993. http://web4.library.adelaide.edu.au/theses/09AR/09arb229.pdf.
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Roth, Gerhard 1952. "A consensus approach to primitive extraction." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41142.
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This thesis applies the consensus paradigm to an important problem in model-based vision, that of primitive extraction. Primitive extraction is the process of finding geometric primitives in geometric data. Such data are obtained directly by active sensors such as laser rangefinders, by processes that operate on passive sensor data to create depth information such as stereo vision, or by simple edge detection and thresholding of intensity images. A geometric primitive is a curve or surface which can be described by an implicit function. We show that the best solution to this problem is at the global optimum of a cost function which often has very many local optima.<br>This global optimum represents the best consensus in the data with regard to the extraction problem. The consensus paradigm attempts to find this global optimum by randomly choosing small subsets of the data and evaluating the cost function for each subset. We apply the consensus paradigm to this problem by randomly sampling minimal subsets. This is a simple and general way of finding the best consensus. For primitive extraction a minimal subset is the smallest number of points necessary to define a geometric primitive. The issues of how to choose the appropriate cost function, how to decide on the number of random samples, and how to convert between a minimal subset and the parameter vector that defines the primitive are explored in detail.<br>While effective, the consensus approach using random sampling often requires a large number of random samples, and therefore a large number of cost function evaluations. We address this problem by combining the consensus paradigm with a genetic algorithm that uses the minimal subset representation. A genetic algorithm is an optimization method based on the evolutionary metaphor. It has been successfully applied to difficult optimization problems, where the cost function is noisy, multi-dimensional, and has many local minima. In our applications the genetic algorithm is able to use local geometric information to produce a global solution in a way that usually avoids the problem of premature commitment. The resulting method often requires far fewer cost function evaluations than the random sampling approach. Some ways of implementing these algorithms on different parallel architectures are described.
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Hu, Yuebing, and 胡跃冰. "Consensus control of multi-agent systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B4658657X.
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Sillitoe, Ian. "Consensus templates for protein structure recognition." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404942.
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Raab, Jonathan David. "Consensus-building in electric utility regulation." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/28010.
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Hornik, Kurt, and David Meyer. "Deriving Consensus Rankings from Benchmarking Experiments." Department of Statistics and Mathematics, WU Vienna University of Economics and Business, 2006. http://epub.wu.ac.at/1300/1/document.pdf.
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Whereas benchmarking experiments are very frequently used to investigate the performance of statistical or machine learning algorithms for supervised and unsupervised learning tasks, overall analyses of such experiments are typically only carried out on a heuristic basis, if at all. We suggest to determine winners, and more generally, to derive a consensus ranking of the algorithms, as the linear order on the algorithms which minimizes average symmetric distance (Kemeny-Snell distance) to the performance relations on the individual benchmark data sets. This leads to binary programming problems which can typically be solved reasonably efficiently. We apply the approach to a medium-scale benchmarking experiment to assess the performance of Support Vector Machines in regression and classification problems, and compare the obtained consensus ranking with rankings obtained by simple scoring and Bradley-Terry modeling.<br>Series: Research Report Series / Department of Statistics and Mathematics
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Garg, Mohit. "Generalized Consensus for Practical Fault-Tolerance." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/85049.
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Despite extensive research on Byzantine Fault Tolerant (BFT) systems, overheads associated with such solutions preclude widespread adoption. Past efforts such as the Cross Fault Tolerance (XFT) model address this problem by making a weaker assumption that a majority of processes are correct and communicate synchronously. Although XPaxos of Liu et al. (using the XFT model) achieves similar performance as Paxos, it does not scale with the number of faults. Also, its reliance on a single leader introduces considerable downtime in case of failures. This thesis presents Elpis, the first multi-leader XFT consensus protocol. By adopting the Generalized Consensus specification from the Crash Fault Tolerance model, we were able to devise a multi-leader protocol that exploits the commutativity property inherent in the commands ordered by the system. Elpis maps accessed objects to non-faulty processes during periods of synchrony. Subsequently, these processes order all commands which access these objects. Experimental evaluation confirms the effectiveness of this approach: Elpis achieves up to 2x speedup over XPaxos and up to 3.5x speedup over state-of-the-art Byzantine Fault-Tolerant Consensus Protocols.<br>Master of Science<br>Online services like Facebook, Twitter, Netflix and Spotify to cloud services like Google and Amazon serve millions of users which include individuals as well as organizations. They use many distributed technologies to deliver a rich experience. The distributed nature of these technologies has removed geographical barriers to accessing data, services, software, and hardware. An essential aspect of these technologies is the concept of the shared state. Distributed databases with multiple replicated data nodes are an example of this shared state. Maintaining replicated data nodes provides several advantages such as (1) availability so that in case one node goes down the data can still be accessed from other nodes, (2) quick response times, by placing data nodes closer to the user, the data can be obtained quickly, (3) scalability by enabling multiple users to access different nodes so that a single node does not cause bottlenecks. To maintain this shared state some mechanism is required to maintain consistency, that is the copies of these shared state must be identical on all the data nodes. This mechanism is called Consensus, and several such mechanisms exist in practice today which use the Crash Fault Tolerance (CFT). The CFT model implies that these mechanisms provide consistency in the presence of nodes crashing. While the state-of-the-art for security has moved from assuming a trusted environment inside a firewall to a perimeter-less and semi-trusted environment with every service living on the internet, only the application layer is required to be secured while the core is built just with an idea of crashes in mind. While there exists comprehensive research on secure Consensus mechanisms which utilize what is called the Byzantine Fault Tolerance (BFT) model, the extra costs required to implement these mechanisms and comparatively lower performance in a geographically distributed setting has impeded widespread adoption. A new model recently proposed tries to find a cross between these models that is achieving security while paying no extra costs called the Cross Fault Tolerance (XFT). This thesis presents Elpis, a consensus mechanism which uses precisely this model that will secure the shared state from its core without modifications to the existing setups while delivering high performance and lower response times. We perform a comprehensive evaluation on AWS and demonstrate that Elpis achieves 3.5x over the state-of-the-art while improving response times by as much as 50%.
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Argyle, Sean Francis. "Mathematical thinking: From cacophony to consensus." Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1337696397.
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Nzigou-Moussavou, Alain. "Désir et consensus : éléments d'anthropobiologie érotique." Paris 8, 2009. http://www.theses.fr/2009PA083127.
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Fondant toutes les institutions, parlant dans toute parole, le désir est ce dont la rationalité argumentative prônée par l'éthique transcendantale de la discussion ne peut nous guérir, car c'est en lui seul qu'elle peut énoncer son rêve de transformation communicationnelle de l'homme en consensus universel et éternel avec lui-même, les autres et le monde. Rêve dont la réalisation sociopolitique est à jamais différée. Ainsi découvre-t-on qu'"Homo consensus" est un "Homo eroticus" condamné à errer inexorablement sur la mer impétueuse du monde, embarqué dans la nef de l'incertitude généralisée. Ballotté d'une rive fantasmatique à l'autre par les bourrasques de ses croyances idéologiques, il contemple de loin son objet de gratification qui se tient, phénoménologiquement et ontologiquement, obstinément dans la "distance épistémique", terre promise qui rend ivre, mais où on ne pourra jamais vivre. Ici, le fantasme est absolument total, et la jouissance seulement orale. C'est pourquoi la "sédimentation consensuelle" qui tente, par la pétrification sémantique du signe institué dans la ritualisation culturelle, de combler la béance ouverte par cette distance épistémique, doit être perpétuellement subvertie par la "transformation érotique" qui déploie les rémiges du jugement par lequel l'homme, limier sur ses propres trousses, réfléchit les bases rectrices et tectrices de sa circonstance sociohistorique et ses principes axiologiques. S'annonce ainsi la seule vérité qu’il y ait à découvrir : l'homme est au monde pour désirer (le consensus) et il "désire (le consensus)" pour être au monde, mais le temps qui fait venir à lui le désir ne lui donne pragmatiquement l'être qu'au gré de ses saisons<br>Founding all institutions, talking in all speech, the desire is that of which the argumentative rationality extolled by the transcendental ethics of the discussion cannot heal us, because it is in it only that it can express its dream of communicational transformation of the man in universal and eternal consensus with himself, the others and the world. Dream whose socio-political realization is deferred forever. Finally "Homo consensus" is only a "Homo eroticus" condemned to wander inexorably on the impetuous sea of the world, on-board in the nave of the generalized uncertainty. Tossed of a phantasmatical strand to the other by the squalls of his ideological beliefs, he contemplates from afar his object of tip that is held, phenomenologically and ontologically, stubbornly in the epistemic distance, promised earth that returns intoxicated, but where one will never live. Here, the fantasy is absolutely total, and the enjoyment only oral. It is why the "consensual sedimentation" that tempts, by the semantic fixation of the sign instituted in the cultural rituals, to fill the hole opened by this epistemic distance, must be subverted perpetually by the "erotic transformation" that opens out the work of the judgment by which the man, bloodhound on his own kits, revalues the roots of his socio-historical circumstance and his axiological principles. Announce himself the only truth that to discover has thus: the man is at the world to want (the consensus) and he "wants (the consensus)" to be at the world, but the time that makes the desire come to him gives him being pragmatically only as and it wants, by the will of its seasons
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Morrow, Jeffrey A. "Tracking consensus in product development teams /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/10694.
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Crosscombe, Michael. "Exploiting vagueness for multi-agent consensus." Thesis, University of Bristol, 2018. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.743033.
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Terelius, Håkan. "Consensus Algorithms in Dynamical Network Systems." Licentiate thesis, KTH, Reglerteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-133613.
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Dynamical network systems are complex interconnected systems describing many real world problems. The current trend is to connect more and more systems together, and at the same time requiring continuous availability. To this end, it is crucial to understand the dynamic behaviors of networked systems.This thesis makes three contributions in this area. First, we study the important problem of gathering data that are distributed among the nodes in a network. Two specific tasks are considered: to estimate the size of the network, and to aggregate the distribution of local measurements generated by the nodes. We consider a framework where the nodes require anonymity, and restricted computational resources. We propose probabilistic algorithms with low resource requirements, that quickly generate arbitrarily accurate estimates. For dynamical networks, we improve the accuracy through a regularization term which captures the trade-off between the gathered data and a-priori assumptions on the dynamics. In the second part of this thesis, we consider a dynamical network system where one node is misbehaving due to a failure. We specifically seek robustness conditions that guarantee that the entire network system is still functional. The nodes' dynamics is governed by consensus updates, and we present thresholds on the interaction strengths that determines if the system will reach consensus, or if the system will diverge. Finally, a P2P network is utilized to improve a live-streaming media application. In particular, we study how an overlay network, constructed from simple preference functions, can be used to build efficient topologies that reduce both network latency and interruptions. We present necessary and sufficient convergence conditions, as well as convergence speed estimates, and demonstrate the improvements for a real P2P video streaming application.<br><p>QC 20131111</p>
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Carli, Ruggero. "Topics on the Average Consensus Problems." Doctoral thesis, Università degli studi di Padova, 2008. http://hdl.handle.net/11577/3426744.
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Driven by fundamental technological achievements like the digital revolution in communication and computing and the miniaturization of electronic components, a growing interest in the field of networked systems has appeared, in recent years, in different scientific areas like physics, communication and control engineering, economy, and lately, mathematics. Besides
differences among the various approaches, the basic model consists of a certain number of agents, namely, systems living in a common environment and which communicate among each other according to some pre-specified communication pattern. Such a pattern may be fixed or varying according to their physical position, to their internal state and can possibly be affected by noises. The evolution law of each system typically depends on the information obtained through its communication links and is, in general, modeled by a difference or differential equation. For this type of models, the interest is, in general, in studying time evolution, asymptotic behaviors, and in formulating and solving related control problem. In particular, a fundamental issue is understanding the emerging of a group behavior from the individual dynamics and the communication pattern. While many models have already been proposed, the mechanisms which determine how the various individual actions get reflect in the group behavior are, in general, hard to understand and, up to now, few results are known.
In this thesis we will focus on the so-called consensus problem, where the group of agents has to reach an agreement on key pieces of information or on a common decision (represented by scalar or vector values) that enable them to cooperate in a coordinate fashion. We will consider a standard algorithm proposed in literature to solve this problem. We will provide some theoretical developments by
• characterizing the speed of convergence of this algorithm for particular communication pattern exhibiting symmetries,
• investigating the realistic and practical situation in which the systems can communicate each other only through digital channels and hence can exchange only quantized information,
• proposing the application of this algorithm to a problem of distributed estimation.
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Genta, L. "CONSENSUS-BASED CROWDSOURCING: TECHNIQUES AND APPLICATIONS." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/263749.
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Crowdsourcing solutions are receiving more and more attention in the recent literature about social computing and distributed problem solving. In general terms, crowdsourcing can be considered as a social-computing model aimed at fostering the autonomous formation and emergence of the so-called wisdom of the crowd. Quality assessment is a crucial issue for the effectiveness of crowdsourcing systems, both for what concerns task and worker management. Another aspect to be considered in crowdsourcing systems is about the kind of contributions workers can make. Usually, crowdsourcing approaches rely only on tasks where workers have to decide among a predefined set of possible solutions. On the other hand, tasks leaving the workers a higher level of freedom in producing their answer (e.g., free-hand drawing) are more difficult to be managed and verified. In the Thesis, we present the LiquidCrowd approach based on consensus and trustworthiness techniques for managing the xecution of collaborative tasks. By collaborative task, we refer to a task for which a factual answer is not possible/appropriate, or a task whose result depends on the personal perception/point-of-view of the worker. We introduce the notion of worker trustworthiness to denote the worker “reliability”, namely her/his capability to foster
the successful completion of tasks. Furthermore, we improve the conventional score-based mechanism by introducing the notion of award that is a bonus provided to those workers that contribute to reach the consensus within groups. This way, groups with certain trustworthiness requirements can be composed on-demand, to deal with complex tasks, like for example tasks where consensus has not been reached during the first execution. In LiquidCrowd , we define a democratic mechanism based on the notion of supermajority to enable the flexible specification of the expected degree of agreement required for obtaining the consensus within a worker group. In LiquidCrowd , three task typologies are provided: choice, where the worker is asked to choose the answer among a list of predefined options; range, where the worker is asked to provide a free-numeric answer; proposition, where the worker is asked to provide a free text answer.
To evaluate the quality of the produced results obtained through LiquidCrowd consensus techniques, we perform a testing against the SQUARE crowdsourcing benchmark. Furthermore, to evaluate the capability of LiquidCrowd to effectively support a real problem, real case studies about web data classification have been selected.
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Mahamdi, Célia. "Multi-Consensus distribué : agrégation et révocabilité." Electronic Thesis or Diss., Sorbonne université, 2024. http://www.theses.fr/2024SORUS426.
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Cette thèse présente deux contributions dans le domaine des systèmes distribués : OMAHA et le Consensus f-Révocable. OMAHA (Opportunistic Message Aggregation for pHase-based Algorithms) est un mécanisme d'agrégation de messages conçu pour les algorithmes à phases. Dans les environnements Cloud, où plusieurs applications partagent la même infrastructure, la bande passante est une ressource critique. Dans les datacenters, une partie importante du trafic est consacrée aux petits messages. Chaque message possède un en-tête, ainsi, l'accumulation de ces petits messages pose un véritable problème et entraîne une consommation non négligeable de bande passante. Plusieurs mécanismes ont été proposés pour adresser ce défi, mais peu d'entre eux prennent en compte les caractéristiques applicatives. Ils reposent principalement sur une agrégation des messages au niveau de la couche réseau. OMAHA exploite les spécificités des algorithmes à phases pour agréger intelligemment et de manière opportuniste les messages. Bien que gourmands en messages, de très nombreuses applications reposent sur des algorithmes à phases (Google Spanner, Zookeeper, etc.). Cependant, ils possèdent un avantage majeur : des communications prévisibles. En anticipant les futures communications, OMAHA retarde les messages en les regroupant avec d'autres destinés au même processus. Cela permet de réduire le nombre de messages envoyés sur le réseau et donc une économie de bande passante. Nos expériences montrent des économies de bande passante allant jusqu'à 30%, tout en limitant la dégradation de la latence à 5% pour le célèbre algorithme de Paxos. Dans les systèmes distribués, atteindre un consensus sur une action ou une valeur est un défi complexe, surtout lorsque les processus sont soumis à des contraintes. De nombreux systèmes, tels que les systèmes multi-agents (véhicules autonomes, gestion d'agenda, robotique, etc.) ou encore les systèmes d'allocation de ressources, doivent respecter des contraintes tout en atteignant un objectif global commun. Cependant, les algorithmes de consensus traditionnels ne prennent pas en compte ces contraintes, la décision se basant uniquement sur les valeurs proposées par les processus. Une solution triviale consisterait à recueillir toutes les contraintes, mais en raison de l'asynchronisme et des pannes, cela est impossible. Pour tolérer les pannes, certains algorithmes définissent un nombre maximal de fautes qu'ils peuvent supporter. Cela permet à l'algorithme de progresser sans attendre la réponse de tous les processus. En conséquence, la valeur décidée est souvent imposée par un sous-ensemble de processus, la majorité. Les contraintes de la minorité sont ainsi ignorées. Pour répondre à ce problème, nous avons introduit le Consensus f-Révocable. Ce consensus revisité permet de choisir une valeur qui respecte les contraintes des processus tout en offrant la possibilité de révoquer une décision prise par la majorité si celle-ci viole les contraintes d'un processus de la minorité. La convergence est assurée car le nombre de révocations est borné par le nombre de processus appartenant à la minorité. Nous avons développé deux adaptations de l'algorithme Paxos pour mettre en pratique ce nouveau consensus<br>This thesis presents two contributions to the field of distributed systems: OMAHA and the f-Revoke Consensus.OMAHA (Opportunistic Message Aggregation for pHase-based Algorithms) is a message aggregation mechanism designed for phase-based algorithms. In cloud environments, multiple applications share the same infrastructure, making bandwidth a critical resource. A significant portion of traffic in data centers consists of small messages. Each message includes a header, leading to substantial bandwidth consumption. Several mechanisms have been proposed to address this issue, but few consider application-specific characteristics. Most rely on aggregation at the network layer. OMAHA leverages the features of phase-based algorithms to intelligently and opportunistically aggregate messages. Many applications, such as Google Spanner and Zookeeper, depend on phase-based algorithms. They are often message-intensive but offer a key advantage: predictable communications. By anticipating future communications, OMAHA delays messages and groups them with others intended for the same process. This approach reduces the number of messages sent over the network, resulting in bandwidth savings. Our experiments show bandwidth saving of up to 30%, while limiting latency degradation to 5% for the well-known Paxos algorithm. In distributed systems, achieving consensus on an action or value is complex, especially when processes face constraints. Many systems, including multi-agent systems (like autonomous vehicles and robotics) and resource allocation systems, need to respect these constraints while working towards a common goal. Unfortunately, traditional consensus algorithms often overlook these constraints, focusing only on the values proposed by the processes. A straightforward solution would be to gather all constraints, but due to asynchrony and potential failures, this is impossible. To handle failures, some algorithms set a limit on the number of faults they can tolerate. This allows them to move forward without waiting for responses from every process. As a result, the final decision is made by a subset of processes known as the majority. This leads to the exclusion of constraints from the minority. To tackle this problem, we introduced the f-Revoke Consensus. This new approach enables the selection of a value that considers processes' constraints. It also allows for the revocation of a majority decision if it violates the constraints of a minority process. Importantly, convergence is ensured because the number of revocations is limited by the size of the minority. We developed two adaptations of the Paxos algorithm to implement this new consensus
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Puente-Palacios, Katia, Tatiana Moreira, Tamara Puente, and Naianne Lira. "Strategic consensus predicting outputs of team performance." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/101680.
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Strategic consensus in work teams is a group process related to the shared comprehension among team members of the strategies defined to attain work goals. This study aimedto verify the predictive power of strategic consensus in relation to team performance. The prediction model was constructed based on data collected from teachers and coordi-nators of 70 educational institutions in Ecuador. The individual data were aggregated per institution to obtain group level scores. The results indicate that strategic consensus predicts about 6% of the team performance as rated by the coordinator. We concluded that more studies are required to gain a better understanding of the role of strategic consensus in workteams.<br>El consenso estratégico en equipos de trabajo es un proceso grupal relativo a la comprensióncompartida entre los integrantes, sobre las estrategias definidas para alcanzar las metas de trabajo. El estudio realizado buscó verificar la capacidad de predicción del consenso estratégico en relación al desempeño. Los datos fueron recogidos de docentes y coordinadores de 70 planteles educativos ecuatorianos, a partir de los que se construyó el modelo de predicción. Las respuestas individuales fueron agregadas por plantel para obtener puntajes grupales. Los resultados mostraron que el consenso estratégico predice aproximadamente 6% de los resultados del desempeño del equipo evaluado por el coordinador. Concluimos que son necesarios más estudios para entender mejor el papel del consenso en equipos de trabajo.
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Yu, Libo. "Consensus Fold Recognition by Predicted Model Quality." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/1124.
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Protein structure prediction has been a fundamental challenge in the biological field. In this post-genomic era, the need for automated protein structure prediction has never been more evident and researchers are now focusing on developing computational techniques to predict three-dimensional structures with high throughput.
Consensus-based protein structure prediction methods are state-of-the-art in automatic protein structure prediction. A consensus-based server combines the outputs of several individual servers and tends to generate better predictions than any individual server. Consensus-based methods have proved to be successful in recent CASP (Critical Assessment of Structure Prediction).
In this thesis, a Support Vector Machine (SVM) regression-based consensus method is proposed for protein fold recognition, a key component for high throughput protein structure prediction and protein function annotation. The SVM first extracts the features of a structural model by comparing the model to the other models produced by all the individual servers. Then, the SVM predicts the quality of each model. The experimental results from several LiveBench data sets confirm that our proposed consensus method, SVM regression, consistently performs better than any individual server. Based on this method, we developed a meta server, the Alignment by Consensus Estimation (ACE).
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Brzozowski, Richard. "Canadian abortion legislation consensus, conflict or compromise?" Thesis, University of Ottawa (Canada), 1986. http://hdl.handle.net/10393/4563.
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Kaas, Johansen Andreas. "Exploring consensus mediating arguments in online debates." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-227858.
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This work presents a first venture into the search for features that define the rhetorical strategy known as Rogerian rhetoric. Rogerian rhetoric is a conflictsolving rhetorical strategy intended to find common ground instead of polarizing debates further by presenting strong arguments and counter arguments, as is often done in debates. The goal of the thesis is to lay the groundwork, a feature exploration and an evaluation of machine learning in this domain, for others tempted to model consensus-mediating arguments. In order to evaluate different sets of features statistical testing is applied to test if the distribution of certain features differ over consensus-mediating comments compared to nonconsensus mediating comments. Machine Learning in this domain is evaluated using support vector machines and different featuresets. The results show that on this data the consensus-mediating comments do have some characteristics that differ from other comments, some of which may generalize across debates. Next, as consensus-mediating arguments proved to be rare, these comments are a minority class, and in order to classify them using machine learning techniques overfitting needs to be addressed, the results suggest that the strategy applied to deal with overfitting is highly important. Due to the bias inherent in the hand annotated dataset the results should be considered provisional, more studies using debates from more domains with either expert or crowdsourced annotations are necessary to take the research further and produce results that generalize well.<br>Detta arbete presenterar en första resa in i eftersökningen för egenskaper som definierar den retoriska strategin kallat Rogerian Rhetoric. Rogerian Rhetoric är en konfliktlösande retorikstrategi skapat för att hitta en gemensam grund, istället för att polarisera debatten ytterligare genom att presentera starka och motstridiga argument, som det ofta görs. Målet med denna uppsats är att skapa det underliggande jobbet, en egenskapsundersökning och en evaluering av maskininlärning i denna domän, för andra som tänker att modellera konsensusförmedlade kommentarer. For at kunna evaluera olika sätt av egenskaper används statistiska tester. För att kunna testa om bestämda egenskaper varierar i konsensusförmedlade kommentarer sammanhållit med icke-konsensus förmedlade kommentarer. Maskininlärning i denna domän är evaluerat genom användning av support vector machine och olika egenskapssätt. Resultatet visar att på det använda datasätt har de konsensusförmedlade kommentarerna några karakteristika som skiljer sig från andra kommentarer, några av dom generaliserar på tvärs av debatter. Eftersom konsensusförmedlade kommentarer är sällsynta, är dissa kommentar en minority class och för att kunna klassificera genom användande av maskininlärningstekniker måste overfitting hanteras, resultatet visar att vilken strategi som man använder till overfitting är av högsta betydning. Grundet biasen som uppstår i det manuellt-kategoriserat datasätt skal resultatet anses för att provisorisk, behöves fler studier på debatter inom andra domänen göras, äntligen med expert eller crowdsourced kategoriseringar för att ta forskningen till nästa steg och producera resultat som sen kan används brett.
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Cámara, Hagen Luis Tomás. "A consensus based Bayesian sample size criterion." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ64329.pdf.
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O'Callaghan, Terry. "Consensus and international relations : a critical inquiry /." Title page, abstract and contents only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09pho15.pdf.
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Brubaker, Dale M. "Predicting strength of consensus in small groups." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08222009-040244/.
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Bernsel, Andreas, Håkan Viklund, Aron Hennerdal, and Arne Elofsson. "TOPCONS : consensus prediction of membrane protein topology." Stockholms universitet, Institutionen för biokemi och biofysik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-34577.
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TOPCONS (http://topcons.net/) is a web server for consensus prediction of membrane protein topology. The underlying algorithm combines an arbitrary number of topology predictions into one consensus prediction and quantifies the reliability of the prediction based on the level of agreement between the underlying methods, both on the protein level and on the level of individual TM regions. Benchmarking the method shows that overall performance levels match the best available topology prediction methods, and for sequences with high reliability scores, performance is increased by approximately 10 percentage points. The web interface allows for constraining parts of the sequence to a known inside/outside location, and detailed results are displayed both graphically and in text format.
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Tran-The, Hung. "Problème du Consensus dans le Modèle Homonyme." Phd thesis, Université Paris-Diderot - Paris VII, 2013. http://tel.archives-ouvertes.fr/tel-00925941.
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So far, the distributed computing community has either assumed that all the processes of a distributed system have distinct identifiers or, more rarely, that the processes are anonymous and have no identifiers. These are two extremes of the same general model: namely, n processes use l different identifiers, where 1 l n. We call this model homonymous model. To determine the power of homonymous model as well as the importance of identifiers in distributed computing, this thesis studies the consensus problem, one of the most famous distributed computing problem. We give necessary and sufficient conditions on the number of identifiers for solving consensus in a distributed system with t faulty processes in the synchronous case. We show that in crash, send omission and general omission failures model, the uniform consensus is solvable even if processes are anonymous. Thus, identifiers are not useful in that case. However identifiers become important in Byzantine failures model: 3t + 1 identifiers is necessary and sufficient for Byzantine agreement. Surprisingly the number of identifiers must be greater than n+3t 2 in presence of three facets of uncertainty: partial synchrony, Byzantine failures and homonyms. This demonstrates two differences from the classical model (which has l = n): there are situations where relaxing synchrony to partial synchrony renders agreement impossible, and, in the partially synchronous case, increasing the number of correct processes can actually make it harder to reach agreement.
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Üstebay, Deniz. "Efficient distributed consensus in wireless sensor networks." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114428.
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Many applications of wireless sensor networks can be formulated as instances of the distributed average consensus problem. This problem involves reaching a network state where each node has the same value---the average of the initial values. Reaching a consensus can be challenging in practical scenarios where the network topology varies in time due to node mobility or unreliable wireless communication links. Randomized gossip algorithms are attractive methods for such scenarios because they do not require specialized routes; they rely on asynchronous updates between random pairs of nodes. However, the communication overhead of gossip is high on topologies that are generally used for modeling wireless sensor networks. Here we propose novel gossip algorithms that reach the consensus with fewer wireless transmissions compared to randomized gossip.We first propose greedy gossip with eavesdropping. This algorithm takes advantage of the broadcast nature of wireless transmissions such that nodes eavesdrop on the updates in their neighborhood. Consequently, when a node wakes up for gossip update, instead of choosing a neighbor randomly, it chooses the neighbor which has the most different value than its own. We prove that greedy updates in this fashion are guaranteed to converge faster than randomized gossip and the communication savings can be expressed as a function of the maximum number of neighbors in the network.Then we move on to studying the problem of reaching consensus on a high-dimensional vector. Although consensus on the entries of a vector can be achieved by running gossip in parallel for each entry, this can be wasteful when only few entries of the vector are significant. This thesis presents threshold and top-m selective gossip algorithms which aim to reach a consensus only on the significant entries of the consensus vector. Both algorithms focus communication resources at each update on exchanging only the significant entries of the local vectors. We prove that such myopic updates identify the significant entries of the consensus vector successfully. Using these algorithms, we propose novel approaches to decentralized compression and distributed particle filtering in wireless sensor networks. Numerical experiments demonstrate communication savings over existing methods.The methods proposed in this thesis are appropriate alternatives to randomized gossip because they do not require additional information to be transmitted beyond local neighborhoods. Taken together our results indicate that it is possible to decrease the communication overhead of randomized gossip while preserving its attractive properties.<br>De nombreuses applications des réseaux de capteurs sans fil peuvent être formulées comme des cas particuliers du problème de consensus moyenné distribué. Ce problème nécessite d'atteindre un état du réseaux où tous les capteurs ont la même valeur; à savoir la moyenne des valeurs initiales. Arriver à un tel consensus peut représenter un défi dans certains scénarios pratiques si la topologie du réseau change au cours du temps, par exemple à cause de la mobilité des capteurs ou un manque de fiabilité des liens sans fil. Dans ces cas particuliers, les algorithmes de colportage sont des alternatives attrayantes étant donné qu'ils n'ont pas besoin de routes spécifiques: ils dépendent d'échanges asynchrones effectués entre les capteurs. Cependant, la communication supplémentaire ajoutée par le colportage est élevée pour les topologies utilisées pour modeler les réseaux de capteurs sans fil. Nous proposons ici de nouveaux algorithmes de colportage qui arrivent à un consensus en utilisant moins de transmissions sans fil que le colportage aléatoire. Nous proposons tout d'abord un algorithme de colportage avec écoute du voisinage. Cet algorithme profite de la nature des transmissions sans fils pour épier les échanges dans le voisinage. Ainsi, quand un noeud se réveille pour une mise à jour de l'algorithme de colportage, au lieu de choisir un noeud voisin en manière aléatoire, il choisit le voisin qui a la valeur la plus éloignée de la sienne. Nous prouvons que ces mises à jour sont garanties de converger plus rapidement que le colportage aléatoire et que l'économie en terme de communication peut être exprimée en fonction du nombre maximum de voisins dans le réseau. Nous étudions ensuite le problème d'arriver à un consensus sur un vecteur de grande dimension. Le consensus sur les composantes d'un vecteur peut être réalisé avec l'utilisation du colportage en parallèle pour chaque composante. Cependant cette façon peut être peu économique dans le cas où seulement quelques composantes sont significatives. Cette thèse présente deux algorithmes, dénommés colportage sélectif seuil et top-m, qui visent à arriver à un consensus seulement sur les composantes significatives du vecteur considéré. Les deux algorithmes se focalisent sur l'utilisation des ressources de communication à chaque mise à jour en échangant seulement les composantes significatives du vecteur local. Nous prouvons que de telles mises à jour identifient avec succès les composantes significatives du vecteur. Utilisant ces algorithmes, nous proposons de nouvelles méthodes pour la compression décentralisée et les filtres à particules distribués dans les réseaux de capteurs. Nos expériences numériques démontrent que des économies de communication sont réalisées sur les méthodes existantes. Les algorithmes proposés dans cette thèse sont des alternatives appropriées au colporatage aléatoire parce qu'ils n'ont pas besoin de l'information additionnelle qui doit être transmise au-delà du voisinage proche. Pris dans leur ensemble, nos résultats indiquent qu'il est possible de diminuer l'excès de communication du colportage aléatoire tout en gardant ses propriétés bénéfiques.
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Lehaney, Brian. "Simulation modelling in administration-by-consensus organisations." Thesis, Brunel University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286696.
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