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91.
The evaluation of the work of a researcher and its impact on the research community has been deeply studied in literature through the definition of several measures, first among all the h-index and its variations. Although these measures represent valuable tools for analyzing researchers?? outputs, they usually assume the co-authorship to be a proportional collaboration between the parts, missing out their relationships and the relative scientific influences. In this work, we propose the d-index, a novel measure that estimates the dependence degree between authors on their research environment along their entire scientific publication history. We also present a web application that implements these ideas and provides a number of visualization tools for analyzing and comparing scientific dependences among all the scientists in the DBLP bibliographic database. Finally, relying on this web environment, we present case and user studies that highlight both the validity and the reliability of the proposed evaluation measure. 相似文献
92.
Gianluca Paravati Andrea Sanna Fabrizio Lamberti Luigi Ciminiera 《Mobile Networks and Applications》2011,16(3):385-393
Wireless communication advances have enabled emerging video streaming applications to mobile handheld devices. For example,
it is possible to display and interact with complex 3D virtual environments on mobile devices that don’t have enough computational
and storage capabilities (e.g. smart phones, PDAs) through remote rendering techniques, where a server renders 3D data and
streams the corresponding image flow to the client. However, due to fluctuations in bandwidth characteristics and limited
mobile device CPU capabilities, it is extremely challenging to design effective systems for streaming interactive multimedia
over wireless networks. This paper presents a novel approach based on a controller that can automatically adjust streaming
parameters basing on feedback measures from the client device. Experimental results prove the effectiveness of the proposed
solution in coping with bandwidth changes, thus providing high Quality of Service (QoS) in remote visualizations. 相似文献
93.
Luigi Catuogno Hans Löhr Mark Manulis Ahmad-Reza Sadeghi Christian Stüble Marcel Winandy 《Datenschutz und Datensicherheit - DuD》2010,34(5):289-294
Trusted Virtual Domains (TVDs) provide a secure IT infrastructure offering a homogeneous and transparent enforcement of access
control policies on data and network resources. In this article, we give an overview of the fundamental ideas and basic concepts
behind TVDs, present a realization of TVDs, and discuss application scenarios. 相似文献
94.
Desmin and troponin T are degraded faster in type IIb muscle fibers than in type I fibers during postmortem aging of porcine muscle 总被引:1,自引:0,他引:1
A novel approach was applied in this study to directly evaluate the effect of muscle fiber type on postmortem protein degradation. Porcine muscle fibers were isolated from longissimus muscle at day 1, 3, and 6 postmortem. Fibers were sorted by immunochemical myosin heavy chain isoform typing. Western blot analysis of fibers pooled separately into type I or IIb showed that the relative amounts of 39- and 50-kDa desmin degradation fragments at day 6, and 28- to 31-kDa fragments of troponin T fast type isoform (fTnT) at day 1 and 6 postmortem were higher in type IIb than in type I fibers. At day 6 troponin T slow type isoform (sTnT) was less degraded than fTnT in type I fibers. These results indicated greater rate and extent of proteolysis in type IIb than in type I fibers and higher susceptibility of fTnT to proteolysis than that of sTnT isoform. 相似文献
95.
Francesco Venditti Francesca Cuomo Andrea Ceglie Luigi Ambrosone Francesco Lopez 《Journal of hazardous materials》2010,173(1-3):552-557
The feasibility of utilizing CTAB–silica gelatin composite (C-SGC) to remove hexavalent chromium from aqueous solutions under different conditions was investigated. Removal of chromate was assessed through evaluation of the adsorption kinetics of chromate ions on the composite under equilibrium conditions in the presence of sulfate ions and at a slightly acidic pH condition (pH 5.8). Adsorption competition tests in the presence of sulfate ions showed that Cr(VI) was still effectively adsorbed from aqueous solution regardless of the presence of the competing anions. In fact, the adsorption kinetics performed at different initial chromate concentrations were unaffected by the presence of 100 mg L?1 sulfate ions (pH 7.5). The equilibrium adsorption data were fitted by Freundlich adsorption isotherms which confirmed that the adsorption efficiency of chromium on the CTAB–silica gelatin composite was unchanged in the presence of sulfate ions. Further, the adsorption process was shown to be pH dependent and more efficient at slightly acidic pH (5.8). These findings demonstrated a high specificity of the CTAB–silica gelatin composite for chromium, and highlight the possibility of using this matrix for efficient removal of chromium from industrial wastewater without the need to eliminate contaminant sulfate ions. 相似文献
96.
Gelatin nanoparticles produced by a simple W/O emulsion as delivery system for methotrexate 总被引:3,自引:0,他引:3
Cascone MG Lazzeri L Carmignani C Zhu Z 《Journal of materials science. Materials in medicine》2002,13(5):523-526
Biodegradable hydrophilic gelatin nanoparticles, containing different initial amounts of methotrexate (MTX), were prepared using a simple solvent evaporation technique based on a single water-in-oil emulsion and stabilized by the use of glutaraldehyde as cross-linking agent. The effects of several parameters on particle size, drug encapsulation efficiency and drug release were investigated. Size and shape of the nanoparticles were examined by scanning electron microscopy. The release of MTX was monitored in vitro and the mechanism of release was studied. Particles with a mean diameter of 100–200 nm were produced, which were able to release MTX following a diffusion-controlled mechanism of release. It was observed that the initial amount of MTX used for sample loading did not have any effect on the pattern of release, while it affected the amount of drug entrapped into the nanoparticles and also both the release rate and the total amount of drug released. 相似文献
97.
An integrated optical waveguide refractometer, believed to be novel, is presented. The sensor is based on an antiresonant reflecting optical waveguide and uses the strong attenuation dependence on the refractive index of antiresonant cladding layers as the sensing principle. The theory and the operation of the sensor are discussed in terms of one- and two-dimensional geometry. The theoretical predictions and numerical analysis show that a versatile sensor can be realized. The design trade-offs are discussed, and the sensitivity and measurement range are presented. 相似文献
98.
Luigi Palopoli Domenico Rosaci Giorgio Terracina Domenico Ursino 《Knowledge and Information Systems》2005,8(4):462-497
The problem of handling both the integration and the cooperation of a large number of information sources characterised by
heterogeneous representation formats is a challenging issue. In this context, a central role can be played by the knowledge
about the semantic relationships holding between concepts belonging to different information sources (intersource properties).
In this paper, we propose a semiautomatic approach for extracting two kinds of intersource properties, namely synonymies and
homonymies, from heterogeneous information sources. In order to carry out the extraction task, we introduce both a conceptual
model, for representing involved sources, and a metrics, for measuring the strength of the semantic relationships holding
among concepts represented within the same source. 相似文献
99.
This article addresses the problem of detecting feature interactions in the area of telephony systems design. The proposed approach consists of two phases: filtering and testing. The filtering phase detects possible interactions by identifying incoherencies in a logic specification of the main elements of the features, consisting of preconditions, triggers, results and constraints. If incoherencies are identified, then an interaction is suspected, test cases corresponding to the suspected interaction are generated and testing is applied to see if the interaction actually exists. Two case studies, carried out on established benchmarks, show that this approach gives good results in practice.
Nicolas Gorse received a Master of Computer Science from the University of Ottawa, School of Information Technology and Engineering in 2001.He is currently a Ph.D. candidate in the Département d'Informatique et Recherche Opérationnelle of the Université de Montréal. His research interests relate to formal methods and their application in the design and verification of complex electronic systems at high levels of abstraction.
Luigi Logrippo received a degree in law from the University of Rome (Italy) in 1961, and in the same year he started a career in computing. He worked for several computer companies and in 1969 he obtained a Master of Computer Science from the University of Manitoba, followed by a Ph.D. of Computer Science from the University of Waterloo in 1974.He was with the University of Ottawa for 29 years, where he was Chair of the Computer Science Department for 7 years. In 2002 he moved to the Université du Québec en Outaouais, Département d'Informatique et Ingénierie, while remaining associated with the University of Ottawa as an Adjunct Professor.His interest area is formal and logic-based methods and their applications in the design of communications systems. For a number of years he worked on the development of tools and methods for the language LOTOS. Current research deals with the formal analysis of advanced communications services made possible by internet telephony, of the policies that govern them, and of their interactions, in application areas such as presence features and e-commerce contracts.
Jacques Sincennes is a research programmer/systems analyst at the University of Ottawa, School of Information Technology and Engineering. He has held this position for the past 17 years. He is coauthor of a number of papers and a patent application.An erratum to this article is available at . 相似文献
100.
Paolo Casoli Andrea Vacca Germano Franzoni Gian Luigi Berta 《Simulation Modelling Practice and Theory》2006,14(8):1059
This paper presents a numerical model for the simulation of a swash-plate axial piston pump, focusing on the characterization of fluid properties.As it is well known, the reduction of flow oscillations (which generates pressure ripples and produces vibration and noise in the entire circuit) and the avoidance of cavitation are the major problems in the design of these pumps. Developing a simulation code can be very useful for component optimisation in order to predict and reduce the undesired phenomena. The paper first gives a quick overview on a previously developed pump model; afterwards four different models of the fluid are presented: they take into account cavitation in different ways. Their aim at characterizing as well as possible the unsteady and erratic cavitation features in a simplified manner, in order to apply the models to the simulation of hydraulic components.In the second part of the paper an application is shown of these models to an axial piston pump: a few results are presented and compared with available test data. The effects of the fluid models on the predicted pump performance are shown and commented. 相似文献