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Scaling up publish/subscribe overlays using interest correlation for link sharing

Matos, Miguel; Felber, Pascal; Oliveira, Rui Carlos Mendes de; Pereira, José, 1973-; Rivière, Etienne
Fonte: IEEE Computer Society Publicador: IEEE Computer Society
Tipo: Pré-impressão
Publicado em //2013 Português
Relevância na Pesquisa
37.27781%
Documento submetido para revisão pelos pares. Publicado em "IEEE transactions on parallel and distributed systems", vol. 24, nr. 12 (Dec. 2013), p. 2462-2471. DOI 10.1109/TPDS.2013.6; Topic-based publish/subscribe is at the core of many distributed systems, ranging from application integration middleware to news dissemination. Therefore, much research was dedicated to publish/subscribe architectures and protocols, and in particular to the design of overlay networks for decentralized topic-based routing and efficient message dissemination. Nonetheless, existing systems fail to take full advantage of shared interests when disseminating information, hence suffering from high maintenance and traffic costs, or construct overlays that cope poorly with the scale and dynamism of large networks. In this paper we present StaN, a decentralized protocol that optimizes the properties of gossip-based overlay networks for topicbased publish/subscribe by sharing a large number of physical connections without disrupting its logical properties. StaN relies only on local knowledge and operates by leveraging common interests among participants to improve global resource usage and promote topic and event scalability. The experimental evaluation under two real workloads...

Global priority setting for Cochrane systematic reviews of health promotion and public health research

Doyle, J; Waters, E; Yach, D; McQueen, D; De Francisco, A; Stewart, T; Reddy, P; Gulmezoglu, A; Galea, G; Portela, A
Fonte: BMJ Group Publicador: BMJ Group
Tipo: Artigo de Revista Científica
Publicado em /03/2005 Português
Relevância na Pesquisa
46.29469%
Background: Systematic reviews of health promotion and public health interventions are increasingly being conducted to assist public policy decision making. Many intra-country initiatives have been established to conduct systematic reviews in their relevant public health areas. The Cochrane Collaboration, an international organisation established to conduct and publish systematic reviews of healthcare interventions, is committed to high quality reviews that are regularly updated, published electronically, and meeting the needs of the consumers.

Solving Bluetooth deficiencies through publish and subscribe systems

Huang, Jessica Yu-Tien, 1981-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 87 p.; 4361877 bytes; 4371450 bytes; application/pdf; application/pdf
Português
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Research in pervasive computing aims to fully integrate computing devices into our everyday environments in a seamless and efficient manner. Wireless technology such as Bluetooth takes us a step closer by replacing traditional cable connections with a more searnless communication transport, adding mobility and more human-centric computation. However, if we are to fully integrate this technology, we must first address some of its shortcomings, particularly those with respect to areas with a high density of Bluetooth devices. Four of these shortcomings: susceptibility to anonymous attacks, poor power management, synchrony requirement, and lack of friendships stem from the tight coupling of device interactions during the discovery protocol. One solution to this problem uses the advantages of publish and subscribe systems to decouple this interaction between smart mobile devices. Available devices can announce their availability to a central controller while devices interested in finding others can announce their interests. When a match occurs, the controller notifies both parties and provides information on how they can form a direct connection. This solution preserves the functionality of the Bluetooth connection protocol while circumventing the four shortcomings. The assumptions it makes are reasonable when placed in a the context of personal computing environment. Future considerations include optimizations that utilize caching...

A flight software development and simulation framework for advanced space systems

Enright, John Patrick, 1974-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 314 p.; 13073081 bytes; 13072882 bytes; application/pdf; application/pdf
Português
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Distributed terrestrial computer systems employ middleware software to provide communications abstractions and reduce software interface complexity. Embedded applications are adopting the same approaches, but must make provisions to ensure that hard real-time temporal performance can be maintained. This thesis presents the development and validation of a middleware system tailored to spacecraft flight software development. Our middleware runs on the Generalized Flight Operations Processing Simulator (GFLOPS) and is called the GFLOPS Rapid Real-time Development Environment (GRRDE). GRRDE provides publish-subscribe communication services between software components. These services help to reduce the complexity of managing software interfaces. The hard real-time performance of these services has been verified with General Timed Automata modelling and extensive run-time testing. Several example applications illustrate the use of GRRDE to support advanced flight software development. Two technology-focused studies examine automatic code generation and autonomous fault protection within the GRRDE framework. A complex simulation of the TechSat 21 distributed spacebased radar mission highlights the utility of the approach for large-scale applications.; by John Patrick Enright.; Thesis (Ph. D.)--Massachusetts Institute of Technology...

Melanesian elites and modern politics in New Caledonia and Vanuatu

Wittersheim, Eric
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Working/Technical Paper Formato: 187902 bytes; 360 bytes; application/pdf; application/octet-stream
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Much research has been conducted into the processes of ‘invention of tradition’ and ‘construction of national identity’ in Melanesia often focusing on the opposition between tradition and modernity. Oppositions like local versus national, rural versus urban, traditional versus westernised or authenticity versus inauthenticity have been emphasised; sometimes with reason, sometimes not. Even if many researchers no longer take for granted such analytical frameworks, lots of areas remain unexplored. The experience of the leaders who emerged in the 1960s and 1970s in Melanesia is one such neglected area. The ‘tradition versus modernity’ discourse usually describes a huge gap between these leaders, seen as westernized and alienated from their culture, and the people, who are ‘simply living’ this culture. Following Hobsbawm in particular, many scholars have seen the discourses they developed as spurious traditions justifying political manipulations. This was quite different from my own experience. During a trip in the South Pacific in 1991, I met some of the leaders of the Front de Libération Nationale Kanak Socialiste (FLNKS) in New Caledonia, and everything in their daily life and their discourses seemed to contradict this idea of an ontological difference between tradition and modernity. These individuals all had a prominent role within the FLNKS...

Discovery and Reuse of Modeling and Simulation Assets / Paper 10S-SIW-048

Gustavson, Paul; Dumanoir, Paul; Blais, Curtis; Daehler-Wilking, Richard
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Trabalho em Andamento
Português
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Approved for public release; distribution is unlimited.; Documents include Paper & Powerpoint Presentation.; The ability to discover existing modeling and simulation (M&S) assets is a critical need for enabling effective reuse and for reducing the duplication of capabilities. Such visibility and accessibility is key to optimizing the investment of the estimated billions of dollars spent on M&S within the Department of Defense (DoD). This paper updates the status of work presented at the SISO 2009 Spring SIW (09S-SIW-076). The DoD M&S Community of Interest (COI) Discovery Metadata Specification (MSC-DMS) version 1.2.1, which provides a common mechanism to catalog a wide variety of M&S resources as metacards, is now publicly available through the DoD Metadata Registry. A formal process has been established to coordinate the MSC-DMS and the closely related specification used by the DoD M&S Catalog. The M&S Catalog provides a common portal with connection to various M&S related repository sources, and is expected to be declared operational in early 2010. In addition, the M&S Catalog will be federated with the DoD Enterprise Catalog, and publish-and-subscribe mechanisms using DoD Net-Centric Enterprise Services (NCES) will be developed. Tools will be developed and technical assistance provided to help sources map their existing data structures to the MSC-DMS...

Zunun Kadir's Ambiguity: The dilemma of a Uyghur writer under Chinese rule

Thwaites, Dilber
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD); Doctor of Philosophy (PhD)
Português
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This thesis considers the work of the influential Uyghur writer Zunun Kadir (1912-1989), and through it charts some aspects of Uyghur identity and aspiration, while explaining the background of his work in relation to the culture and history of the Uyghur people of East Turkistan (Xinjiang). Growing up in a poor and conservative family under Chinese rule, Zunun developed a commitment to nationalism and socialism in the belief that these would serve as the best basis for the advancement of the Uyghur people. In middle age he witnessed the absorption of the East Turkistan Republic into the People’s Republic of China (PRC) established by the Chinese Communist Party, and he adapted himself to work under that government. This involved accepting a political agenda that called upon him to support a unified greater China to the detriment of Uyghur national interests. This situation presented Zunun Kadir with an enduring dilemma: how to resist the cultural domination of the Han Chinese and maintain the distinct cultural identity of the Uyghur people, while ensuring his freedom to write and publish in an environment controlled by the CCP. In the volatile political environment of the PRC, this balance could not be maintained indefinitely and Zunun was eventually subjected to official criticism and sent to the Tarim desert to undergo labour reform. After 17 years of exile he was rehabilitated in the Deng Xiaoping era...

Hospitality Research: How to Plan, Fund, Execute, and Publish

Kopenhaver, Lendal H.; O'Brien, William
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
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Researchers interested in exploring topics of concern to the hospitality industry can discover a wide range of areas to be explored and a variety of sources to fund the research. The authors discuss a four-step plan for conducting and publishing quality research, including tips for the writing process.

Ordering, Timeliness and Reliability for Publish/Subscribe Systems over WAN

PLATANIA, MARCO
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
Português
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In the last few years, the increasing use of the Internet and geo-political, sociological and financial changes induced by globalization, are paving the way for a connected world where the information is always available at the right place and the right time. As such, applications previously deployed for ``closed'' environmets, are now federating into geographically distributed systems connected through a Wide Area Network (WAN). By this evolution, in the near future no system will be isolated: every system will be composed by interconnected systems, i.e., it will be a System of Systems (SoS). Example of SoS are the Large-scale Complex Critical Infrastructure (LCCIs), such as power grids, transport infrastructures (airports and seaports), financial infrastructures, next generation intelligence platforms, to cite a few. In these systems, multiple sources of information generate a high volume of events that need to be delivered to all intended destinations by respecting several Quality of Service (QoS) constraints imposed by the critical nature of LCCIs. As such, particular attention is devoted to the middleware solution used to disseminate information in the SoS. Due to its inherently scalability provided by space, time and synchronization decoupling properties...

Um escritor e ilustrador (Odilon Moraes), uma editora (Cosac Naify) : criação e fabricação de livros de literatura infantil; A writer and ilolustrator (Olilon Moraes), a public house (Cosac Naify) : creation and production of infantile literature books

Andrea Rodrigues Dalcin
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 05/02/2013 Português
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Este trabalho tem como propósito conhecer o processo de criação e produção de livros de literatura infantil, pela visão do autor e ilustrador Odilon Moraes. O corpus é constituído por três obras publicadas pela Editora Cosac Naify, escritas e ilustradas pelo referido autor: "A Princesinha Medrosa" (2ª edição, 2008), "Pedro e Lua" (2004) e "O Presente" (2010). A pesquisa se volta para as singularidades dos modos de criação e produção, a partir da análise das representações e concepções de criança, literatura e arte que concebem um determinado jogo circunscrito no polo da produção, por este autor e esta editora. Para tanto, levantamos as seguintes interrogações: no caso da literatura infantil, como as representações do leitor infantil são sugeridas no momento da criação das obras pelos autores? Como é o jogo, no polo da produção, quando pensamos neste autor e nesta editora? Como este jogo questiona (ou não) o jogo habitual ancorado em uma sociedade de mercado e de consumo? Para buscarmos respostas, tomamos como fontes documentais entrevistas com o autor, com Isabel Lopes Coelho, editora do catálogo de literatura infantojuvenil da Cosac Naify, e com Maria Carolina Sampaio de Araújo, designer. Nessa direção...

Feedback loops in educational environments using web-based survey tools : new technology development and three implementation case studies

Spead, Benjamin, 1978-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 240 p.; 19147252 bytes; 19178657 bytes; application/pdf; application/pdf
Português
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This thesis presents lessons from the development of an on-line, web-based feedback system and preliminary analysis of the socio-technical interactions associated with the specification, design and use of this system. The system has been designed to facilitate many forms of feedback in educational environments. Novel technical components of the system include: (1) a highly detailed and flexible data model representing the social-system feedback loops, (2) reusable feedback objects and sub-objects which minimize content entry requirements while improving data aggregation capabilities, and (3) feedback objects which respond dynamically based on the context in which they are used. Novel social system learning associated with this thesis centers on the mechanisms to facilitate feedback in academic and industry learning environments. This thesis features the design, implementation, and preliminary use of the Online Feedback Organization, Requesting and Monitoring for Educators (OnFORME) system. OnFORME was created to enable ubiquitous feedback collection in a semi-transparent manner for educators in both academic and corporate training environments. OnFORME provides a way for educators to quickly author feedback objects (e.g. surveys) and publish them via the World Wide Web so that students can easily respond. The author used agile development methodology to design and implement this application directly from customer use cases in a bottom-up approach. Inductive research methods included observations of thirteen potential adoption trials...

Dynamics, robustness and fragility of trust

Pavlovic, Dusko
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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46.29916%
Trust is often conveyed through delegation, or through recommendation. This makes the trust authorities, who process and publish trust recommendations, into an attractive target for attacks and spoofing. In some recent empiric studies, this was shown to lead to a remarkable phenomenon of *adverse selection*: a greater percentage of unreliable or malicious web merchants were found among those with certain types of trust certificates, then among those without. While such findings can be attributed to a lack of diligence in trust authorities, or even to conflicts of interest, our analysis of trust dynamics suggests that public trust networks would probably remain vulnerable even if trust authorities were perfectly diligent. The reason is that the process of trust building, if trust is not breached too often, naturally leads to power-law distributions: the rich get richer, the trusted attract more trust. The evolutionary processes with such distributions, ubiquitous in nature, are known to be robust with respect to random failures, but vulnerable to adaptive attacks. We recommend some ways to decrease the vulnerability of trust building, and suggest some ideas for exploration.; Comment: 17 pages; simplified the statement and the proof of the main theorem; FAST 2008

S-ToPSS: Semantic Toronto Publish/Subscribe System

Petrovic, Milenko; Burcea, Ioana; Jacobsen, Hans-Arno
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/11/2003 Português
Relevância na Pesquisa
37.06817%
The increase in the amount of data on the Internet has led to the development of a new generation of applications based on selective information dissemination where, data is distributed only to interested clients. Such applications require a new middleware architecture that can efficiently match user interests with available information. Middleware that can satisfy this requirement include event-based architectures such as publish-subscribe systems. In this demonstration paper we address the problem of semantic matching. We investigate how current publish/subscribe systems can be extended with semantic capabilities. Our main contribution is the development and validation (through demonstration) of a semantic pub/sub system prototype S-ToPSS (Semantic Toronto Publish/Subscribe System).; Comment: 4 pages, 2 figures, VLDB 2003 demo (29th International Conference on Very Large Databases)

I know what you mean: semantic issues in Internet-scale publish/subscribe systems

Burcea, Ioana; Petrovic, Milenko; Jacobsen, Hans-Arno
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 27/11/2003 Português
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37.201194%
In recent years, the amount of information on the Internet has increased exponentially developing great interest in selective information dissemination systems. The publish/subscribe paradigm is particularly suited for designing systems for routing information and requests according to their content throughout wide-area network of brokers. Current publish/subscribe systems use limited syntax-based content routing but since publishers and subscribers are anonymous and decoupled in time, space and location, often over wide-area network boundary, they do not necessarily speak the same language. Consequently, adding semantics to current publish/subscribe systems is important. In this paper we identify and examine the issues in developing semantic-based content routing for publish/subscribe broker networks.; Comment: 12 pages, 1 figure, SWDB 2003 (1st Workshop on Semantic Web and Databases)

Performance Evaluation of Hierarchical Publish-Subscribe Monitoring Architecture for Service-Oriented Applications

Zuzak, Ivan; Benc, Ivan
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/09/2012 Português
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46.957993%
Contemporary high-performance service-oriented applications demand a performance efficient run-time monitoring. In this paper, we analyze a hierarchical publish-subscribe architecture for monitoring service-oriented applications. The analyzed architecture is based on a tree topology and publish-subscribe communication model for aggregation of distributed monitoring data. In order to satisfy interoperability and platform independence of service-orientation, monitoring reports are represented as XML documents. Since XML formatting introduces a significant processing and network load, we analyze the performance of monitoring architecture with respect to the number of monitored nodes, the load of system machines, and the overall latency of the monitoring system.; Comment: 7 pages, 5 figures

General Complex Polynomial Root Solver and Its Further Optimization for Binary Microlenses

Skowron, J.; Gould, A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/03/2012 Português
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46.29916%
We present a new algorithm to solve polynomial equations, and publish its code, which is 1.6-3 times faster than the ZROOTS subroutine that is commercially available from Numerical Recipes, depending on application. The largest improvement, when compared to naive solvers, comes from a fail-safe procedure that permits us to skip the majority of the calculations in the great majority of cases, without risking catastrophic failure in the few cases that these are actually required. Second, we identify a discriminant that enables a rational choice between Laguerre's Method and Newton's Method (or a new intermediate method) on a case-by-case basis. We briefly review the history of root solving and demonstrate that "Newton's Method" was discovered neither by Newton (1671) nor by Raphson (1690), but only by Simpson (1740). Some of the arguments leading to this conclusion were first given by the British historian of science Nick Kollerstrom in 1992, but these do not appear to have penetrated the astronomical community. Finally, we argue that Numerical Recipes should voluntarily surrender its copyright protection for non-profit applications, despite the fact that, in this particular case, such protection was the major stimulant for developing our improved algorithm.; Comment: 29 pages...

FaceBots: Steps Towards Enhanced Long-Term Human-Robot Interaction by Utilizing and Publishing Online Social Information

Mavridis, Nikolaos; Emami, Shervin; Datta, Chandan; Kamzi, Wajahat; BenAbdelkader, Chiraz; Toulis, Panos; Tanoto, Andry; Rabie, Tamer
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/04/2009 Português
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46.3073%
Our project aims at supporting the creation of sustainable and meaningful longer-term human-robot relationships through the creation of embodied robots with face recognition and natural language dialogue capabilities, which exploit and publish social information available on the web (Facebook). Our main underlying experimental hypothesis is that such relationships can be significantly enhanced if the human and the robot are gradually creating a pool of shared episodic memories that they can co-refer to (shared memories), and if they are both embedded in a social web of other humans and robots they both know and encounter (shared friends). In this paper, we are presenting such a robot, which as we will see achieves two significant novelties.

Xitris: A Software to Acquire, Display, Compress, and Publish Data in Real Time using Distributed Mode for the Solar Radio Interferometer RIS

De la Luz, Victor; Lara, Alejandro
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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56.74433%
Upgrading the infrastructure of old scientific instruments requires the development of new hardware and software which may be expensive (in general, these projects lack of enough resources to acquire fast and modern infrastructure to become ompetitive and functional in the era of digital data). Particularly, the development of software for data acquisition in real time is one of the most important topics in experimental science and industry. However, the constant improvements on the data acquisition hardware, discourages the development of software highly optimized in order to minimize the consumption of resources like processor time and read/write memory, etc. In this work, we present a Open Source code called X Interface to RIS (Xitris). This is a modular and distributed code which, using relatively slow processors and low memory hardware, is able to acquire, display, compress and publish (via Internet) digital data in real time. Xitris was developed for the Solar Radio Interferometer (RIS) at Geophysics Institute of the National University of Mexico (UNAM) but nowadays is working in another 3 radio observatories.; Comment: Accepted in JCIS

Unifying Databases and Internet-Scale Publish/Subscribe

Chandramouli, Badrish
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação Formato: 3205992 bytes; application/pdf
Publicado em 01/08/2008 Português
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With the advent of Web 2.0 and the Digital Age, we are witnessing an unprecedented increase in the amount of information collected, and in the number of users interested in different types of information. This growth means that traditional techniques, where users poll data sources for information of interest, are no longer sufficient. Polling too frequently does not scale, while polling less often may result in users missing important updates. The alternative push technology has long been the goal of publish/subscribe systems, which proactively push updates (events) to users with matching interests (expressed as subscriptions). The push model is better suited for ensuring scalability and timely delivery of updates, important in many application domains: personal (e.g., RSS feeds, online auctions), financial (e.g., portfolio monitoring), security (e.g., reporting network anomalies), etc.

Early publish/subscribe systems were based on predefined subjects (channels), and were too coarse-grained to meet the specific interests of different subscribers. The second generation of content-based publish/subscribe systems offer greater flexibility by supporting subscriptions defined as predicates over message contents. However, subscriptions are still stateless filters over individual messages...

Greater transparency at the Fed has led to better informed, though sterile, internal debate and discussion

Hansen, Stephen; McMahon, Michael; Prat, Andrea
Fonte: The London School of Economics and Political Science Publicador: The London School of Economics and Political Science
Tipo: Website; NonPeerReviewed Formato: application/pdf
Publicado em 03/02/2014 Português
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If central banks publish the transcripts of their internal policy debates, will discussions be enhanced or inhibited? Stephen Hansen, Michael McMahon and Andrea Prat use tools from computational linguistics to analyze the positive and negative effects of transparency on deliberations of the monetary policymakers at the US Federal Reserve