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141.
142.
Sidney Roberto Carvalho Ubirajara Franco Moreno 《Journal of The Franklin Institute》2021,358(9):5039-5072
In distributed and cooperative systems, the network structure is determinant to the success of the strategy adopted to solve complex tasks. Those systems are primarily governed by consensus protocols whose convergence is intrinsically dependent on the network topology. Most of the consensus algorithms deal with continuous values and perform average-based strategies to reach cohesion over the exchanged information. However, many problems demand distributed consensus over countable values, that cannot be handled by traditional protocols. In such a context, this work presents an approach based on semidefinite programming to design the optimal weights of a network adjacency matrix, in order to control the convergence of a distributed random consensus protocol for variables at the discrete-space domain, based on the voter model. As a second contribution, this work uses Markov theory and the biological inspiration of epidemics to find out a dynamical spreading model that can predict the information diffusion over this discrete consensus protocol. Also, convergence properties and equilibrium points of the proposed model are presented regarding the network topology. Finally, extensive numerical simulations evaluate the effectiveness of the proposed consensus algorithm, its spreading model, and the approach for optimal weight design. 相似文献
143.
Eduardo N. Borges Moisés G. de Carvalho Renata Galante Marcos André Gonçalves Alberto H.F. Laender 《Information processing & management》2011
Digital libraries of scientific articles contain collections of digital objects that are usually described by bibliographic metadata records. These records can be acquired from different sources and be represented using several metadata standards. These metadata standards may be heterogeneous in both, content and structure. All of this implies that many records may be duplicated in the repository, thus affecting the quality of services, such as searching and browsing. In this article we present an approach that identifies duplicated bibliographic metadata records in an efficient and effective way. We propose similarity functions especially designed for the digital library domain and experimentally evaluate them. Our results show that the proposed functions improve the quality of metadata deduplication up to 188% compared to four different baselines. We also show that our approach achieves statistical equivalent results when compared to a state-of-the-art method for replica identification based on genetic programming, without the burden and cost of any training process. 相似文献
144.
This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller. 相似文献
145.
The European university landscape: A micro characterization based on evidence from the Aquameth project 总被引:2,自引:0,他引:2
Cinzia Daraio Andrea BonaccorsiAldo Geuna Benedetto LeporiLaurent Bach Peter BogetoftMargarida F. Cardoso Elena Castro-MartinezGustavo Crespi Ignacio Fernandez de LucioHarold Fried Adela Garcia-AracilAnnamaria Inzelt Ben JongbloedGerhard Kempkes Patrick LlerenaMireille Matt Maria OlivaresCarsten Pohl Tarmo RatyMaria J. Rosa Cláudia S. SarricoLéopold Simar Stig SlipersaeterPedro N. Teixeira Philippe Vanden Eeckaut 《Research Policy》2011,40(1):148-164
This paper provides a new and systematic characterization of 488 universities, from 11 European countries: Finland, France, Germany, Hungary, Italy, Netherlands, Norway, Portugal, Spain, Switzerland and UK. Using micro indicators built on the integrated Aquameth database, we characterize the European university landscape according to the following dimensions: history/foundation of university, dynamics of growth, specialization pattern, subject mix, funding composition, offer profile and productivity. 相似文献
146.
Tércia Zavaglia TorresAuthor VitaeIvo Pierozzi Jr.Author Vitae Nadir Rodrigues PereiraAuthor VitaeAlexandre de CastroAuthor Vitae 《International Journal of Information Management》2011,31(2):121-127
The great contemporary organizational challenge for enterprises is to create a conceptual and methodological framework allows the management of knowledge by means of networks designed for social interaction. This statement is based on the premise that the competitive drive and sustainable success of the company depend on the introduction of new forms of production innovative processes, which can only be ensured through integrated approaches to knowledge management and the incorporation information technologies (IT). This is a reality that has already been accepted by the Brazilian Agricultural Research Corporation (Embrapa, its acronym in Portuguese), a Brazilian research, development, and innovation (RD&I) institution supporting agricultural sector. For some years now, Embrapa has been incorporating what it has learned about knowledge management into its strategic planning process. In this paper, we present a new approach to managing knowledge and information, and we analyze the need for research institutions to administer the knowledge they produce through an RD&I management model based multi- and inter-disciplinary teams, and multi-institutional research networks. 相似文献
147.
Lidwien van de WijngaertAuthor Vitae Willem PietersonAuthor Vitae Marije L. TeerlingAuthor Vitae 《International Journal of Information Management》2011,31(5):415-419
Information technology allows national and local governments to satisfy the needs of citizens in a cost effective way. Unfortunately, citizens still tend to prefer traditional, more costly channels, such as the front desk, phone and mail. Through pilot projects government agencies attempt to influence this behavior of citizens, directing them towards the online channel. With this paper we provide insight into the possibility to influence citizens’ behavior in the complex landscape of multi-channel service provision. The paper systematically compares five pilot projects using a framework that is based on organizational and marketing literature. The results show that socio-psychological factors are crucial in multi-channel management, much more than the technology itself. We conclude that citizens can be directed towards the online channel. However, not all projects are successful. Economic and legal instruments tend to sort more direct effects than communication or service instruments. Moreover, organizational factors such as bureaucracy often hinder eventual success. Choosing a smart and relatively small scope and strong project manager may help to evoke success in directing citizen online behavior. 相似文献
148.
We tested three theories (adult attachment, autonomy/relatedness, and gender roles) to understand relationship satisfaction among 150 British and 170 Turkish adults, all involved in romantic relationships. Avoidance, relatedness, autonomy–relatedness, and masculinity mediated the relationship between culture and romantic relationship satisfaction. Additionally, as anticipated, Turkish participants scored lower on relationship satisfaction and autonomy whereas British participants scored lower on avoidance and relatedness. Contrary to expectation, gender role differences (differences between masculinity and femininity) in the United Kingdom were not significantly smaller than in Turkey. It is concluded that adult attachment provides a useful framework for understanding country-level differences. 相似文献
149.
Modern patent systems are slow, inefficient, expensive, and may result in outcomes that actively harm technological progress. This paper proposes a substantive re-think of these systems and lays a foundation upon which practical solutions can be built. Many solutions proposed in the past, such as prior-art bounties, outsourced examination, and dynamic fee setting, have gone unheeded due to the cost of administering them and the rigidity of the patent system. We explore how distributed ledger technologies (DLTs) enable these major changes by altering the way stakeholders are able to interact with the patent records system. We find that transitioning to a DLT-based patent records system can enable many previously suggested improvements to current patent systems in a flexible, scalable, and transparent manner. The case for such a transition is strengthened when jointly considering the complex but common roots of problems facing modern patent systems, rather than a balkanised set of technical solutions to address each issue independently. Noting that a DLT-based system is not a panacea, we also provide comment on the political, legal, and organisational challenges that must be overcome for such changes to be implemented at scale. 相似文献
150.
Educational Psychology Review - In their recent paper, Chen et al. (Educational Psychology Review, 2021) propose that rest periods between deliberate learning characterize the spacing effect and... 相似文献