1,721,033 research outputs found
The E-volutionary Optical Network
No full textThe evolution of optical communications since its inception in 1970 until our days is briefly reviewed. The emergence of the optical network is explained as a natural corollary of the pervasiveness of optical transmission and the advent of optical amplifiers and WDM. Current evolution is led by the emergence of the IP network as the prevailing client of the WDM layer.527532Giozza, W.F., Conforti, E., Waldman, H., Fibras Ópticas: Tecnologia e Projeto de Sistemas (1991), (in Portuguese), Makron BooksAgrawal, G.P., Fiber-optic communication systems (1997), WileyGreen P.E., Jr., Fiber optic networks (1993)Ramaswami, R., Sivarajan, K., Optical networks: A practical perspective (1998), Morgan Kaufmann PublishersStern, T.E., Bala, K., Multiwavelength optical networks: A layered approach (1999), Addison-WesleyBarry, R.A., Humblet, P.A., Models of blocking probability in all-optical networks with and without wavelength changers (1996) IEEE Journal on Selected Areas in Communications, 14, pp. 858-867. , JuneKovacevic, M., Acampora, A., Benefits of wavelength translation in all-optical clear-channel networks (1996) IEEE Journal on Selected Areas in Communications, 14, pp. 868-880. , JuneWaldman, H., Campelo, D.R., Camelo, R., Dynamic priority strategies for wavelength assignment in WDM rings (2000) 2000 IEEE Global Telecommunications Conference (Globecom'00), Conference Record, pp. 1288-1292. , San Francisco, U.S.A, 27 Nov. - 01 DecSelf-similar network traffic and performance evaluation (2000), K. Park and W. Willinger (Eds.)WileyZhang, H., Service disciplines for guaranteed performance service in packet-switching networks (1995) Proceedings of the IEEE, 83 (10), pp. 1373-1396. , Oc
The E-evolutionary Optical Network
No full textThe evolution of optical communications since its inception in 1970 until our days is briefly reviewed. The emergence of the optical network is explained as a natural corollary of the pervasiveness of optical transmission and the advent of optical amplifiers and WDM. Current evolution is led by the emergence of the IP network as the prevailing client of the WDM layer.INVITED PAPERS7581Giozza, W.F., Conforti, E., Waldman, H., (1991) Fibras Ópticas: Tecnologia e Projeto de Sistemas, , (in Portuguese), Makron BooksAgrawal, G.P., (1997) Fiber-Optic Communication Systems, , WileyGreen P.E., Jr., (1993) Fiber Optic NetworksRamaswami, R., Sivarajan, K., (1998) Optical Networks: A Practical Perspective, , Morgan Kaufmann PublishersStern, T.E., Bala, K., (1999) Multiwavelength Optical Networks: A Layered Approach, , Addison-WesleyBarry, R.A., Humblet, P.A., Models of blocking probability in all-optical networks with and without wavelength changers (1996) IEEE Journal on Selected Areas in Communications, 14, pp. 858-867. , JuneKovacevic, M., Acampora, A., Benefits of wavelength translation in all-optical clear-channel networks (1996) IEEE Journal on Selected Areas in Communications, 14, pp. 868-880. , JuneWaldman, H., Campelo, D.R., Camelo, R., Dynamic priority strategies for wavelength assignment in WDM rings (2000) 2000 IEEE Global Telecommunications Conference (Globecom'00), Conference Record, pp. 1288-1292. , San Francisco, U.S.A, 27 Nov. - 01 Dec(2000) Self-Similar Network Traffic and Performance Evaluation, , K. Park and W. Willinger (Eds.)WileyZhang, H., Service disciplines for guaranteed performance service in packet-switching networks (1995) Proceedings of the IEEE, 83 (10), pp. 1373-1396. , Oc
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Meeting Optical Qos Requirements With Reduced Complexity In Dynamic Wavelength Assignment
No full textPhysical layer impairments may require highly complex implementations of the control plane in dynamic networks with Quality of Service (QoS) constraints. In order to alleviate this problem, we propose that dynamic wavelength assignment should be based on the elementary First-Fit (FF) algorithm using off-line optimized priority lists. It is shown that this may significantly reduce the effects of physical impairments with no additional computational cost for the control of dynamic networks. A simple metric is proposed to evaluate optical QoS taking the performance of the network as a whole. Different heuristics are presented and evaluated. Results show that there are particular lists capable of reducing in four orders of magnitude the probability of FWM impacting network performance. © 2004 IEEE.331333Ramamurthy, B., Datta, D., Feng, H., Heritage, J.P., Mukherjee, B., Impact of transmission impairments on the teletraffic performance of wavelength-routed optical networks (1999) J. Ligthwave Technology, 17, pp. 1713-1723. , OctAli, M., Tancevski, L., Impact of polarization-mode dispersion on the design of wavelength-routed networks (2002) Photonics Technology Letters, 14, pp. 720-722. , MayFonseca, I.E., Ribeiro, M.R.N., Almeida Jr., R.C., Waldman, H., Preserving global optical QoS in FWM impaired dynamic networks (2004) Electronics Letters, 40, pp. 191-192. , FebXu, B., Brandt-Pearce, M., Comparison of FWM- And XPM-induced crosstalk using the Volterra series transfer function method (2003) J. Ligthwave Technology, 21, pp. 40-53. , JanFonseca, I.E., Almeida Jr., R.C., Ribeiro, M.R.N., Waldman, H., Algorithms for FWM-aware routing and wavelength assignment (2003) Proc. IEEE IMOC'03, 2, pp. 707-713. , SepInoue, K., A simple expression for optical FDM network scale considering fiber FWM and optical amplifier noise (1995) J. Ligthwave Technology, 13, pp. 856-861. , MayForghieri, F., Tkach, R.W., Chraplyvy, A.R., Marcuse, D., Reduction of four-wave mixing crosstalk in WDM systems using unequally spaced channels (1994) Photonics Technology Letters, 6, pp. 754-756. , Jun(2002) Spectral Grids for WDM Application: DWDM Frequency Grid, , ITU-T Rec. G.694.1, Ju
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Traffic Engineering And Restoration In Optical Packet Switching Networks By Means Of Ant Colony Optimization
No full textIn this paper, we propose an ACO-based algorithm that can adaptively balance the network load to mitigate congestion, and hence reduce the overall loss of packets in an OPS network. In addition, the proposed algorithm is fault-tolerant, with the recovery from a failed link or node starting even before detection and localization of the failure event. Since both routing and restoration rely on pheromone levels laid by ant-like agents, any failure will be promptly perceived by some ants, which will then try to circumvent the affected part of the network, thus adapting the routing to the new topology. © 2006 IEEE.O'Mahony, M.J., Simeonidou, D., Hunter, D.K., Tzanakaki, A., The application of optical packet switching in future communication networks (2001) IEEE Communications Magazine, 39 (3), pp. 128-135. , MarchAwduche, D., Malcolm, J., Agogbua, J., O'Dell, M., McManus, J., (1999) Requirements for Traffic Engineering Over MPLS, , http://www.ietf.org/rfc/rfc2702.txt, RFC 2702 Informational, Sept, Online, AvailableBonabeau, E., Dorigo, M., Theraulaz, G., Swarm Intelligence - From Natural to Artificial Systems Oxford University Press, 1999, vol. Santa Fe Institute Studies in the Sciences of ComplexityDorigo, M., Stützle, T., (2004) Ant Colony Optimization, , MIT PressGrassé, P.P., La reconstruction du nid et les coordinations interindividuelles chez Bellicoitermes natalenis et Cubitermes sp. La théorie de la stigmergie: Essai d'interprétation des termites constructeurs (1959) Insectes Sociaux, 6, pp. 41-81Di Caro, G., Dorigo, M., AntNet: Distributed stigmergetic control for communications networks (1998) Journal of Artificial Intelligence Research, 9, pp. 317-365Di Caro, G., Dorigo, M., Two ant colony algorithms for best-effort routing in datagram networks (1998) 10th International Conference on Parallel and Distributed Computing and Systems (PDCS'98), , OctoberPavani, G.S., Waldman, H., Callegati, F., Campi, A., Cerroni, W., Adaptive routing in optical packet switching networks using ant colony optimization (2006) 13th International Conference on Telecommunications (ICT 2006), , MaySchoonderwoerd, R., Holland, O., Bruten, J., Rothkrantz, L., Antbased load balancing in telecommunications networks (1997) Adaptive Behaviour, 5 (2), pp. 169-207Pavani, G.S., Waldman, H., Evaluation of an ant-based architecture for all-optical networks (2006) 10th Conference on Optical Network Design and Modelling (ONDM'06), , MayBarán, B., Sosa, R., AntNet - routing algorithm for data networks based on mobile agents (2001) Revista Iberoamericana de Inteligencia Artificial, (12), pp. 75-84Callegati, F., Cerroni, W., Corazza, G., Optimization of wavelength allocation in WDM optical buffers (2001) Optical Networks Magazine, 2 (6), pp. 66-72. , NovemberJacobson, V., Karels, M., Congestion avoidance and control (1990) ACM Computer Communication Review, 18 (4), pp. 314-329. , AugustCincotti, G., Full optical encoders/decoders for photonic IP routers (2004) Journal of Lightwave Technology, 22 (2), pp. 337-342. , FebruaryK. Kompella, Y Rekhter, and Ed., Routing Extensions in Support of Generalized Multi-Protocol Label Switching (GMPLS), RFC 4202 (Proposed Standard), Oct. 2005. [Online]. Available: http://www.ietf.org/rfc/rfc4202.txtKompella, K., Rekhter, Y., (2005) OSPF Extensions in Support of Generalized Multi-Protocol Label Switching (GMPLS), , http://www.ietf.org/rfc/rfc4203.txt, RFC 4203 Proposed Standard, Oct, Online, AvailableDeering, S., Hinden, R., (1998) Internet Protocol, Version 6 (IPv6) Specification, , http://www.ietf.org/rfc/rfc2460.txt, RFC 2460 Draft Standard, Dec, Online, AvailableSim, K.M., Sun, W.H., Ant colony optimization for routing and load-balancing: Survey and new directions (2003) IEEE Transactions on Systems, Man and Cybernetics, Part A, 33 (5), pp. 560-572. , Septembe
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