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61.
Davide Bilò Hans-Joachim Böckenhauer Dennis Komm Richard Královič Tobias Mömke Sebastian Seibert Anna Zych 《Algorithmica》2011,61(2):227-251
A reoptimization problem describes the following scenario: given an instance of an optimization problem together with an optimal
solution for it, we want to find a good solution for a locally modified instance. 相似文献
62.
Olivier Pras Davide Beneventi Didier Chaussy Paul Piette Sandra Tapin-Lingua 《Journal of Materials Science》2013,48(20):6911-6920
In this study, microfibrillated cellulose (MFC) and dendritic copper were used as binder and conductive phase for the elaboration of self-standing conductive films and coatings. A filtration technique was used to prepare MFC/Cu films from particle dispersions in water and ethanol. In aqueous slurries copper oxidized and an additional corona treatment or the use of zinc particles as sacrificial anode were necessary to obtain films with conductivities ranging from 70 to 2500 S m?1, respectively. In ethanol-based MFC/Cu slurries, copper was subjected to limited oxidation. However, the low packing density of conductive particles (below the percolation threshold) led to resistive films which, after densification by calendering, displayed extremely high conductivities, up to 70000 S m?1. Aqueous MFC/Cu slurries were successfully used for the deposition of conductive coatings on copy paper by Mayer rod coating and screen printing, which were subsequently treated by corona discharge and calendering. The obtained coatings displayed intermediate conductivity (i.e. 95 and 570 S m?1 for rod coating and screen printing, respectively), which can be further increased using zinc particles or ethanol-based formulations. 相似文献
63.
64.
Giordano Bruno L.; Rocchesso Davide; McAdams Stephen 《Canadian Metallurgical Quarterly》2010,36(2):462
Sound sources are perceived by integrating information from multiple acoustical features. The factors influencing the integration of information are largely unknown. We measured how the perceptual weighting of different features varies with the accuracy of information and with a listener’s ability to exploit it. Participants judged the hardness of two objects whose interaction generates an impact sound: a hammer and a sounding object. In a first discrimination experiment, trained listeners focused on the most accurate information, although with greater difficulty when perceiving the hammer. We inferred a limited exploitability for the most accurate hammer-hardness information. In a second rating experiment, listeners focused on the most accurate information only when estimating sounding-object hardness. In a third rating experiment, we synthesized sounds by independently manipulating source properties that covaried in Experiments 1 and 2: sounding-object hardness and impact properties. Sounding-object hardness perception relied on the most accurate acoustical information, whereas impact-properties influenced more strongly hammer hardness perception. Overall, perceptual weight increased with the accuracy of acoustical information, although information that was not easily exploited was perceptually secondary, even if accurate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
Simone Ceriani Giulio Fontana Alessandro Giusti Daniele Marzorati Matteo Matteucci Davide Migliore Davide Rizzi Domenico G. Sorrenti Pierluigi Taddei 《Autonomous Robots》2009,27(4):353-371
A trustable and accurate ground truth is a key requirement for benchmarking self-localization and mapping algorithms; on the
other hand, collection of ground truth is a complex and daunting task, and its validation is a challenging issue. In this
paper we propose two techniques for indoor ground truth collection, developed in the framework of the European project Rawseeds, which are mutually independent and also independent on the sensors onboard the robot. These techniques are based, respectively,
on a network of fixed cameras, and on a network of fixed laser scanners. We show how these systems are implemented and deployed,
and, most importantly, we evaluate their performance; moreover, we investigate the possible fusion of their outputs. 相似文献
66.
Trace metals, PCB congeners and DDT homologues were determined in composite sediment samples collected from 10 representative sites along the river Po in two separate seasons. The aim was to identify the most anthropogenically impacted areas for future monitoring programmes and to aid development of Italian sediment quality criteria. The surface samples were collected during low flow conditions. Trace metal concentrations were assayed by electrothermal (Cd, Co, Cr, Cu, Ni, Pb), flame (Fe, Mn, Zn) or hydride generation (As) atomic absorption spectrometry after microwave assisted acid digestion. Hg was determined on solid samples by automated analyser. Organic microcontaminants were determined by gas-chromatography with 63Ni electron capture detector after Soxhlet extraction. Concentrations of trace metals, total PCB and DDT homologues showed two distinct peaks at the sites immediately downstream of Turin and Milan, respectively, and in each case decreased progressively further downstream. Principal component analysis identified three major factors (from a multi-dimensional space of 35 variables) which explained 85-90% of the total observed variance. The first and second factors corresponded to anthropogenic inputs and geological factors on sediment quality; the third included seasonal processes of minor importance. Sediment quality assessment identified Cd, Cu, Hg, Pb, Zn and organic microcontaminants as posing the most serious threats to river sediment quality. A reference site within the Po basin provided useful background values. Moderate pollution by organochlorine compounds was ascribed both to local sources and to atmospheric deposition. 相似文献
67.
Can a Knowledge-Level layer be located in the Semantic Grid infrastructure? Is it possible to design an Agent Communication Language (ACL) which enables Knowledge-Level agents to cooperate in a geographically distributed Semantic Grid despite nodes’ failures or malfunctions? This paper tries to address the above Semantic Grid challenges presenting an agent-based Open Service Architecture which integrates geographically distributed agents in a Semantic Grid. The architecture is well integrated with standard Internet components and technologies and supports communication among Knowledge-Level agents. The role of agents is to retrieve, execute and compose available services providing more sophisticated instances of them. Inter-agent communication is realized by exploiting an advanced Agent Communication Language which supports a fault-tolerant anonymous interaction protocol and satisfies a set of well defined Knowledge-Level programming requirements. Here, we present the design of the architecture and of the Agent Communication Language as well as their implementation. The architecture is evaluated by means of several case studies which highlight the main feature of our proposal. The main advantage of our approach is to demonstrate that different issues, such as high level inter-agent communication and fault tolerance, can be successfully integrated in Grid infrastructures which provide Web Services maintaining a clean design of the architecture and a Knowledge-Level characterization. 相似文献
68.
Levi F Lorini L Calonico D Godone A 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2004,51(10):1216-1224
In this paper we report the accuracy evaluation of the Italian primary frequency standard IEN-CsF1. We discuss the shifts the frequency standard is corrected for and the procedure used for the accuracy evaluation. In the last section we report frequency comparisons of our fountain with those of remote laboratories and with International Atomic Time. 相似文献
69.
TETRA (TErrestrial Trunked RAdio) is a digital mobile radio standard for voice and data transmission. It aims at satisfying
the growing request of applications and facilities coming from professional users and emergency services. The system has been
standardized by ETSI (European Telecommunications Standards Institute) and is provided with an European harmonized frequency
band. The first TETRA networks appeared on the market in 1997. This paper reports TETRA radio performance evaluated via a
simulation software package, named TETRASIM, entirely developed at CSELT according to TETRA specifications. The simulation
results have been obtained for some of the traffic and control channels specified by the standard, in terms of BER (Bit Error
Rate) and MER (Message Erasure Rate). As far as the simulated receiver scheme is concerned, the characteristics of the equivalent
low-pass filters and the adopted synchronization technique are reported. The simulated demodulator uses a differential detection
scheme with soft decision outputs in the case of coded channels. Performance analyses and results comparison are provided
by taking into account the effects of signal-to-noise ratio, co-channel interference, adjacent channel interference, propagation
models defined in the standard and mobile unit speed. The simulation results reported in this work have been included in the
ETR (ETSI Technical Report) “TETRA Designers’ Guide Part 2: Radio and Traffic Performance”.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
70.
Unbundling dynamic capabilities: an exploratory study of continuous product innovation 总被引:12,自引:0,他引:12
In order to understand better the organizational sources ofcontinuous innovation, this paper provides an in-depth analysisof Oticon A/S, a leading company in the hearing-aid industry,which showed an impressive ability to develop new products inthe nineties. Findings highlight that dynamic capabilities aremade up of: knowledge creation and absorption, knowledge integrationand knowledge reconfiguration. Discussion links the findingsto previous literature and shows how these knowledge-based processesare all based on a coherent mix of organizational resources. 相似文献