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71.
Francesco Carbone Jesús Contreras Josefa Z. Hernández Jose Manuel Gomez-Perez 《Expert systems with applications》2012,39(10):8929-8939
Nowadays, especially after the recent financial downturn, companies are looking for much more efficient and creative business processes. They need to place better solutions in the market in a less time with less cost. There is a general intuition that communication and collaboration, especially mixed with Web 2.0 approach within companies and ecosystems, can boost the innovation process with positive impacts on business indicators. Open Innovation within an Enterprise 2.0 context is a one of the most chosen paradigm for improving the innovation processes of enterprises, based on the collaborative creation and development of ideas and products. The key feature of this new paradigm is that the knowledge is exploited in a collaborative way flowing not only among internal sources, i.e. R&D departments, but also among external ones as other employees, customers, partners, etc. In this paper we show how an ontology-based analysis of plain text can provide a semantic contextualization of content support tasks, such as finding semantic distance between contents, and can help in creating relations between people with shared knowledge and interests. Along this paper we will present the results obtained by the adoption of this technology in a large corporate environment like Bankinter, a financial institution, Telefonica I+D, an international telecommunication firm and Repsol, a major oil company in Spain. 相似文献
72.
A hybrid model for real time simulation of urban traffic 总被引:1,自引:0,他引:1
In this paper a hybrid model is presented to predict the behavior of traffic in urban area. Intersections and on/off-ramps are modeled by Colored Timed Petri Nets while road links are modeled by a stochastic discrete time model. It is assumed that vehicle routings at each intersection are stochastic. A Particle Filter algorithm based on the hybrid model is developed to estimate the system state. The validation of the model by using real data is discussed. The limited computational effort required makes the model suitable to be used in simulation-based control schemes for urban traffic. 相似文献
73.
This paper presents a multi-application traffic generator (MTG), aimed at the generation of packets over a LAN. The generated traffic simulates the one produced by a number of both isochronous and anisochronous applications, thus allowing the measurement of a number of parameters relevant to the communication network. From a test point of view, data generated by the MTG system is equivalent to data generated by real applications spread over a LAN. The MTG system is presented, its implementation is described, some figures relevant to the MTG performance are shown, and the statistical analysis which can be performed on the recorded data is briefly introduced. The user manual of the MTG system is referenced in (Celandroni, Ferro, and Potorti 1995). 相似文献
74.
The paper describes the region between a Maxwellian plasma source and a floating surface by a 1D-3 V fully kinetic, electrostatic particle simulation. The electric field is self-consistently computed from the Poisson equation. The secondary electron emission is modelled by considering an expression for the secondary emission coefficient dependent on the primary electron energy and surface materials and a realistic secondary electron distribution function is introduced at the collector surface. The model is able to simulate the space-charge-limited conditions as well as the positively charged wall cases. 相似文献
75.
Steptoe Andrew; Perkins-Porras Linda; Rink Elisabeth; Hilton Sean; Cappuccio Francesco P. 《Canadian Metallurgical Quarterly》2004,23(6):574
This study assessed psychological and social factors predicting 12-month changes in fruit and vegetable consumption achieved by 271 men and women from a low-income population randomized to brief behavioral and nutrition education counseling. Greater increases in fruit and vegetable intake were achieved in the behavioral than in the nutrition education condition (1.49 vs. 0.87 portions per day, p=.021). Increases were predicted by baseline social support for dietary change but not by baseline psychological measures. However, short-term (8-week) changes in dietary self-efficacy, encouragement, anticipated regret, perceived benefits, and knowledge of recommended intake predicted 12-month changes in fruit and vegetable consumption independently of gender, age, ethnicity, income, and baseline intake. These factors accounted for 51% of the superiority of behavioral counseling over nutrition education. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Francesco Calvetti Claudio di Prisco Roberto Nova 《Canadian Metallurgical Quarterly》2004,130(12):1292-1299
Cases of pipeline damage caused by landslides are common in coastal or mountainous regions, where a continuous monitoring/repair activity is planned in order to maintain their serviceability. The analysis of the soil–structure interaction phenomenon can be invoked to improve the planning and design of buried pipelines, to guide monitoring, and to reduce the risk of damage or failure. Two different approaches are considered in this paper: small scale laboratory tests and numerical simulations using the distinct element method (DEM). The experimental setup consists of a box filled with sand and water. Several experiments were performed, in which the diameter and the depth of the tube varied. The numerical simulations are divided in two separate series: in the first, the numerical model is calibrated and its reliability in reproducing the experimental tests is checked; in the second series, the direction of the relative displacement between the tube and the surrounding “numerical soil” varies over the range ±90° with respect to the horizontal. In the latter, both vertical and horizontal components of the drag force are measured and the corresponding interaction diagrams are constructed. The DEM simulations provide useful information about the shape of the failure mechanisms and the force transfer within the soil. 相似文献
77.
We propose an alternative approach to generate languages by means of P systems: building up an appropriate representation
for a string by means of a corresponding membrane structure and then generating the string by visiting the membrane structure
according to a well-specified strategy. To this aim, we consider P systems with active membranes, allowing membrane creation
or division or duplication and dissolution, where the output of a computation may be obtained either by visiting the tree
associated with the membrane structure, or by following the traces of a specific object, called traveller, or sending out
the objects. For each of these approaches, we provide characterizations of recursively enumerable languages based on P systems
that use different sets of operations for modifying the membrane structure.
Francesco Bernardini: He started his Ph.D. at the University of Sheffield in December 2002 after having previously got a master degree in Computer
Science from the University of Pisa in Italy. His research is dedicated to the study of theoretical aspects of membrane computing
(P systems) and discrete models of biological systems based on P systems.
Marian Gheorghe, Ph.D.: His main research interests are in computational models and their applications to software modelling and testing, formal
specifications of agent based systems, software engineering. He was investigating computational power of various generative
devices (regular, context-free, fully initial; grammar systems; L-systems and variants). He is currently interested in natural
computing (membrane calculus) and biological modelling. 相似文献
78.
A method is presented for checking secure information flow in Java bytecode, assuming a multilevel security policy that assigns security levels to the objects. The method exploits the type‐level abstract interpretation of standard bytecode verification to detect illegal information flows. We define an algorithm transforming the original code into another code in such a way that a typing error detected by the Verifier on the transformed code corresponds to a possible illicit information flow in the original code. We present a prototype tool that implements the method and we show an example of application. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
79.
Mathias Bürger Giuseppe Notarstefano Francesco Bullo Frank Allgöwer 《Automatica》2012,48(9):2298-2304
In this paper we propose a novel distributed algorithm to solve degenerate linear programs on asynchronous peer-to-peer networks with distributed information structures. We propose a distributed version of the well-known simplex algorithm for general degenerate linear programs. A network of agents, running our algorithm, will agree on a common optimal solution, even if the optimal solution is not unique, or will determine infeasibility or unboundedness of the problem. We establish how the multi-agent assignment problem can be efficiently solved by means of our distributed simplex algorithm. We provide simulations supporting the conjecture that the completion time scales linearly with the diameter of the communication graph. 相似文献
80.
Cristiana Correia Federico Magnani Chiara Pastore Antonio Cellini Irene Donati Giuseppina Pennisi Ivan Paucek Francesco Orsini Elodie Vandelle Conceio Santos Francesco Spinelli 《International journal of molecular sciences》2022,23(21)
Light composition modulates plant growth and defenses, thus influencing plant–pathogen interactions. We investigated the effects of different light-emitting diode (LED) red (R) (665 nm) and blue (B) (470 nm) light combinations on Actinidia chinensis performance by evaluating biometric parameters, chlorophyll a fluorescence, gas exchange and photosynthesis-related gene expression. Moreover, the influence of light on the infection by Pseudomonas syringae pv. actinidiae (Psa), the etiological agent of bacterial canker of kiwifruit, was investigated. Our study shows that 50%R–50%B (50R) and 25%R–75%B (25R) lead to the highest PSII efficiency and photosynthetic rate, but are the least effective in controlling the endophytic colonization of the host by Psa. Monochromatic red light severely reduced ΦPSII, ETR, Pn, TSS and photosynthesis-related genes expression, and both monochromatic lights lead to a reduction of DW and pigments content. Monochromatic blue light was the only treatment significantly reducing disease symptoms but did not reduce bacterial endophytic population. Our results suggest that monochromatic blue light reduces infection primarily by modulating Psa virulence more than host plant defenses. 相似文献