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61.
Antonio Coronato Massimo Esposito Giuseppe De Pietro 《Personal and Ubiquitous Computing》2009,13(7):527-538
This paper presents semantic models, mechanisms and a service to locate mobile entities in Smart and Intelligent Environments. The key feature of the service is the semantic integration of different positioning systems that not only enables the environment to handle transparently such physical positioning systems, but also to reason on location information coming from different systems and to combine it to obtain higher context information. Indeed, the service relies on the use of ontologies and rules to define a uniform, unambiguous and well-defined model for the location information, independently of the particular positioning system. Moreover, the location service performs logic and reasoning mechanisms to provide both physical and semantic locations of mobile objects and to infer the finest granularity in the case when a mobile object is located by more than one positioning system. Finally, we present an application of the proposed approach to the case of a Smart Hospital. 相似文献
62.
This paper describes the development of a system for measuring surface coordinates (commonly known as "shape measurements") which is able to give the temporal evolution of the position of the tire sidewall in transient conditions (such as during braking, when there are potholes or when the road surface is uneven) which may or may not be reproducible. The system is based on the well-known technique of projecting and observing structured light using a digital camera with an optical axis which is slanted with respect to the axis of the projector. The transient nature of the phenomenon has led to the development of specific innovative solutions as regards image processing algorithms. This paper briefly describes the components which make up the measuring system and presents the results of the measurements carried out on the drum bench. It then analyses the performance of the measuring system and the sources of uncertainty which led to the development of the system for a specific dynamic application: impact with an obstacle (cleat test). The measuring system guaranteed a measurement uncertainty of 0.28 mm along the Z axis (the axial direction of the tire) with a measurement range of 250(X) x 80(Y) x 25(Z) mm(3), with the tire rolling at a speed of up to 30 km/h. 相似文献
63.
Marinella Fossetti Gioacchino Alotta Francesco Basone Giuseppe Macaluso 《Materials and Structures》2017,50(6):240
In order to consider the response of concrete columns confined by FRP and FRCM system, proper models have to be formulated. In this context the present paper shows a generalized criterion for the determination of the increase in strength, in ductility and in dissipated energy for varying corner radius ratio of the cross section and fiber volumetric ratio. The procedure is based on the best fitting of several experimental data and unlike the usual empirical approaches available in the literature, the proposed technique relates the confinement effectiveness to a single parameter representative of the relative stiffness between the original concrete core and the reinforcement system. Furthermore, the proposed analytical models overcomes the limit of many empirical or semi-empirical models given in the literature that are applicable only to specific cases. A comparison with same available models confirm the reliability of the proposed procedure. 相似文献
64.
A. Riccio F. Caputo G. Di Felice S. Saputo C. Toscano V. Lopresto 《Applied Composite Materials》2016,23(3):219-237
The investigation of the mechanical response of fibre-reinforced composite laminates under impact loads can be very difficult due to the occurrence of simultaneous failure phenomena. Indeed, as a consequence of low velocity impacts, intra-laminar damages, like fibre and matrix cracking, and inter-laminar damages, such as delaminations, can take place simultaneously. These damage mechanisms can lead to significant reductions in strength and stability of the composite structure. In this paper a joint numerical-experimental study is proposed which, by means of non-destructive testing techniques (Ultra-sound and thermography) and non-linear explicit FEM analyses, aims to completely characterise the impact induced damage in composite laminates under low velocity impacts. Indeed the proposed numerical tool has been used to improve the understanding of the experimental data obtained by Non-Destructive Techniques. Applications on samples tested according to the AECMA (European Association of Aerospace Manufacturers) prEn6038 standard at three different impact energies are presented. The interaction between numerical and experimental investigation allowed to obtain an exhaustive insight on the different phases of the impact event considering the inter-laminar damage formation and evolution. 相似文献
65.
Giuseppe Antonio Elia Krystan Marquardt Katrin Hoeppner Sebastien Fantini Rongying Lin Etienne Knipping Willi Peters Jean‐Francois Drillet Stefano Passerini Robert Hahn 《Advanced materials (Deerfield Beach, Fla.)》2016,28(35):7564-7579
A critical overview of the latest developments in the aluminum battery technologies is reported. The substitution of lithium with alternative metal anodes characterized by lower cost and higher abundance is nowadays one of the most widely explored paths to reduce the cost of electrochemical storage systems and enable long‐term sustainability. Aluminum based secondary batteries could be a viable alternative to the present Li‐ion technology because of their high volumetric capacity (8040 mAh cm?3 for Al vs 2046 mAh cm?3 for Li). Additionally, the low cost aluminum makes these batteries appealing for large‐scale electrical energy storage. Here, we describe the evolution of the various aluminum systems, starting from those based on aqueous electrolytes to, in more details, those based on non‐aqueous electrolytes. Particular attention has been dedicated to the latest development of electrolytic media characterized by low reactivity towards other cell components. The attention is then focused on electrode materials enabling the reversible aluminum intercalation‐deintercalation process. Finally, we touch on the topic of high‐capacity aluminum‐sulfur batteries, attempting to forecast their chances to reach the status of practical energy storage systems. 相似文献
66.
Gianmarco de Felice Maria Antonietta Aiello Carmelo Caggegi Francesca Ceroni Stefano De Santis Enrico Garbin Natalino Gattesco Łukasz Hojdys Piotr Krajewski Arkadiusz Kwiecień Marianovella Leone Gian Piero Lignola Claudio Mazzotti Daniel Oliveira Corina Papanicolaou Carlo Poggi Thanasis Triantafillou Maria Rosa Valluzzi Alberto Viskovic 《Materials and Structures》2018,51(4):95
Textile Reinforced Mortar (TRM), also known as Fabric Reinforced Mortar or Fabric Reinforced Cementitious Matrix, composites are an emerging technology for the external repair and strengthening of existing structures. For most applications, the effectiveness of the TRM reinforcement relies on its bond performance. This recommendation identifies the best practice to characterize the bond behaviour of TRM. A shear bond test method is proposed to determine the peak axial stress (associated with the maximum load that can be transferred from the structural member to the externally bonded TRM reinforcement), the stress–slip relationship and the failure mode that controls the TRM-to-substrate load transfer capacity. Guidelines on specimen manufacturing, experimental setup, test execution, and determination of test results are provided. 相似文献
67.
Giordano Maria C. Longhi Stefano Barelli Matteo Mazzanti Andrea Buatier de Mongeot Francesco Della Valle Giuseppe 《Nano Research》2018,11(7):3943-3956
Nano Research - The engineering of self-organized plasmonic metasurfaces is demonstrated using a maskless technique with defocused ion-beam sputtering and kinetically controlled deposition. The... 相似文献
68.
A case situation arising in a normal interaction among people is the baseline for discussing properties of the theory of viewpoints. In particular we consider how to ensure agreement on the meaning of certain utterances by agents who have different perspectives on the situation, while maintaning other knowledge as private. We argue that communication should be modeled as adding facts to the common knowledge of agents. We introduce the principle of 'referent sharing' in communications and argue that common knowledge resulting from communication should only use constants whose referent is manifest to the parties involved. 相似文献
69.
70.
Giuseppe DeToffol Francesco Ancilotto Flavio Toigo 《Journal of Low Temperature Physics》1996,102(5-6):381-410
Calculations are presented, based on a Density Functional approach, of the first excited states (l=1) of alkali metal atoms (Cs and Na) in liquid
4He. We find large departures from the spherical bubble in the liquid4He structure when the alkali atom is excited. The shifts from the free atom values of the excitation and emission transition lines are calculated and compared with the experimental results. According to our calculations, the so far unseen radiative deexcitation transition for light alkalis in4He may lie in an unexplored infrared region of the spectrum. 相似文献