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71.
Luis Antón-Canalís Mario Hernández-Tejera Elena Sánchez-Nielsen 《Pattern recognition》2012,45(9):3125-3130
A straightforward algorithm that computes distance maps from unthresholded magnitudes is presented, suitable for still images and video sequences. While results on binary images are similar to classic Euclidean Distance Transforms, the proposed approach does not require a binarization step. Thus, no thresholds are needed and no information is lost in intermediate classification stages. Experiments include the evaluation of spatial and temporal coherence of distance map values, showing better results in both measurements than those obtained with Sobel or Deriche gradients and classic chessboard distance transforms. 相似文献
72.
Cluster Size Optimization in Sensor Networks with Decentralized Cluster-Based Protocols 总被引:1,自引:0,他引:1
Network lifetime and energy-efficiency are viewed as the dominating considerations in designing cluster-based communication protocols for wireless sensor networks. This paper analytically provides the optimal cluster size that minimizes the total energy expenditure in such networks, where all sensors communicate data through their elected cluster heads to the base station in a decentralized fashion. LEACH, LEACH-Coverage, and DBS comprise three cluster-based protocols investigated in this paper that do not require any centralized support from a certain node. The analytical outcomes are given in the form of closed-form expressions for various widely-used network configurations. Extensive simulations on different networks are used to confirm the expectations based on the analytical results. To obtain a thorough understanding of the results, cluster number variability problem is identified and inspected from the energy consumption point of view. 相似文献
73.
Distributed computing for carbon footprint reduction by exploiting low-footprint energy availability
Ward Van HeddeghemAuthor Vitae Willem VereeckenAuthor VitaeDidier ColleAuthor Vitae Mario PickavetAuthor VitaePiet DemeesterAuthor Vitae 《Future Generation Computer Systems》2012,28(2):405-414
Low carbon footprint energy sources such as solar and wind power typically suffer from unpredictable or limited availability. By globally distributing a number of these renewable sources, these effects can largely be compensated for. We look at the feasibility of this approach for powering already distributed data centers in order to operate at a reduced total carbon footprint. From our study we show that carbon footprint reductions are possible, but that these are highly dependent on the approach and parameters involved. Especially the manufacturing footprint and the geographical region are critical parameters to consider. Deploying additional data centers can help in reducing the total carbon footprint, but substantial reductions can be achieved when data centers with nominal capacity well below maximum capacity redistribute processing to sites based on renewable energy availability. 相似文献
74.
Dario Natali Mario Caironi Marco Sampietro Andrew P. Meacham Steven J. Vickers Michael D. Ward 《Optical Materials》2006,28(12):1362-1365
We report on the electrochromic behavior of a dinuclear ruthenium complex, which provides high environmental stability together with an intense absorption maximum at 1237 nm in solution in its +3 oxidation state. To verify its optoelectronic properties, we used this complex as the photoactive material in a planar photodetector prototype for near-infrared light pulses, succeeding in the detection of a train of light pulses at a wavelength of 1280 nm. 相似文献
75.
The current ACL proposals show some shortcomings with respect to the definition of their semantics. Our paper aims at tackling those issues by defining an ACL semantics as a specification of the analytical effects of agent communicative acts. We analyze agent communication in terms of concepts taken from Speech Act Theory, as several researchers have already done, but move away from the mainstream view of artificial agent research, as we define communicative acts in terms of changes at the level of social relationship between agents. We take commitment to be a primitive concept underlying the social dimension of multiagent systems, and define a basic artificial institution whose aim is to provide agents with the means to affect the commitment network that binds them to each other. 相似文献
76.
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
77.
Beardsley Patrick M.; Aceto Mario D.; Cook Charles D.; Bowman Edward R.; Newman Jennifer L.; Harris Louis S. 《Canadian Metallurgical Quarterly》2004,12(3):163
Despite oxycodone's (4,5-epoxy-14-hydroxy-3-methoxy-17-methylmorphinan-6-one) history of clinical use and the attention it has received as a drug of abuse, few reports have documented its pharmacology's relevance to its abuse or its mechanism of action. The purposes of the present study were to further characterize the analgesic effects of oxycodone, its mechanism of action, and its effects in terms of its relevance to its abuse liability. The results indicate that oxycodone had potent antinociceptive effects in the mouse paraphenylquinone writhing, hot-plate, and tail-flick assays, in which it appeared to be acting as a μ-opioid receptor agonist. It generalized to the heroin discriminative stimulus and served as a positive reinforcer in rats and completely suppressed withdrawal signs in morphinedependent rhesus monkeys. These results suggest that the analgesic and abuse liability effects of oxycodone are likely mediated through μ-opioid receptors and provide the first laboratory report of its discriminative stimulus, reinforcing, and morphine cross-dependency effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Michael J. Dube Dennis Bollea William R. Jones Jr. Mario Marchetti Mark J. Jansen 《Tribology Letters》2003,14(1):3-8
Synthetic hydrocarbon liquid lubricants (based on polyalphaolefins) have been developed for use in space applications. These materials have been fully characterized and their physical properties reported which include: kinematic and absolute viscosity, viscosity index, vapor pressure, evaporation, specific gravity, pour point, coefficient of thermal expansion, refractive index, and flow activation energy. In addition, tribological properties under ultrahigh vacuum conditions have been determined. These include: lubricated lifetimes using a spiral orbit tribometer (SOT) and vacuum four-ball wear rates. These values are compared to existing state-of-the-art space lubricants. 相似文献
79.
Modular experimental setup for real‐time analysis of emergent behavior in networks of Chua's circuits 下载免费PDF全文
Massimiliano de Magistris Mario di Bernardo Sabato Manfredi Carlo Petrarca Soudeh Yaghouti 《International Journal of Circuit Theory and Applications》2016,44(8):1551-1571
This paper describes the design, realization and use of an analogical, fully reconfigurable experimental setup to analyze the complex dynamics of networks of chaotic circuits. It reports details of the implementation and characterization of the setup, together with representative results, showing its flexibility and potential. The setup allows to choose arbitrarily the coupling strength and interconnection structure among the circuits, the type of link and to select the parameters of the node dynamics. It has a modular structure, and it can accommodate up to 32 nodes interconnected by at most 32 links. The collective dynamics of a relatively large set of different network structures and configurations has been investigated using the setup. Synchronization, pattern formation and other interesting collective phenomena were observed experimentally, their evidence being reported here as an illustration of the potential of the proposed setup. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
80.
Christian Heuser Mario Marpe Andreas Wucher 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(4):601-604
The kinetic excitation of a solid surface under bombardment with energetic particles is studied via internal electron emission in a metal-insulator-metal junction. In particular, the dependence of the measured tunneling yield on the projectile impact angle is studied. The resulting impact angle distribution is compared with predictions of the total excitation energy profile calculated using the SRIM 2006 Monte Carlo program package. While the calculated profiles fail to explain the experimental data, it is shown that a simple calculation of impact angle dependent projectile backscattering qualitatively reproduces the observed trends. 相似文献