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排序方式: 共有410条查询结果,搜索用时 15 毫秒
61.
Wireless Personal Communications - The wireless ad hoc networks impel the necessity for power control transmission based on interference aware to increase the throughput of the network and the... 相似文献
62.
M. A. Sumesh S. P. Karanth Beno Thomas G. M. Rao M. Viswanathan P. Chakraborty G. N. Rao 《Journal of Infrared, Millimeter and Terahertz Waves》2017,38(2):135-142
Terahertz (THz) radiation perception using uncooled detectors are gaining importance due to the increasing demands in the areas of military, space, and industrial, medical, and surveillance applications. In spite of the efforts of researchers to fill the THz gap, there exists a need for detectors in the range between 15 THz and 30 THz. In this paper, we discuss the development of bolometric detectors whose performance is enhanced by an optical immersion technique and their characterization in the aforesaid range of frequencies. These detectors are characterized by high specific detectivity (D*) of 1.28?×?109 cmHz1/2 W?1 and high radiometric resolution (noise-equivalent temperature difference?=?26 mK) and are fast enough for bolometric detectors (time constant?=?1.7 ms), which make them suitable for spectroscopic and imaging applications. 相似文献
63.
Let f be an unknown multivariate density belonging to a set of densities \(\mathcal{F}_{k^{*}}\) of finite associated Vapnik–Chervonenkis dimension, where the complexity k * is unknown, and ? k ?? k+1 for all k. Given an i.i.d. sample of size n drawn from f, this article presents a density estimate \(\hat{f}_{K_{n}}\) yielding almost sure convergence of the estimated complexity K n to the true but unknown k * and with the property \(\mathbf{E}\{\int|\hat{f}_{K_{n}}-f|\}=\mbox{O}(1/\sqrt{n}\,)\). The methodology is inspired by the combinatorial tools developed in Devroye and Lugosi (Combinatorial methods in density estimation. Springer, New York, 2001) and it includes a wide range of density models, such as mixture models and exponential families. 相似文献
64.
Hu Z Muls B Gence L Serban DA Hofkens J Melinte S Nysten B Demoustier-Champagne S Jonas AM 《Nano letters》2007,7(12):3639-3644
We demonstrate that arrays of nanowires of conjugated polymers can be easily produced by a simple embossing protocol, compatible with very large scale integration technology. The embossing process is shown to have the supplementary virtue to increase the internal degree of order of the nanowires, significantly enhancing their performance. This is applied to the fabrication of nanowire-based devices consisting of a liquid crystalline light-emitting polymer, of a liquid crystalline semiconducting polymer, and of an amorphous conducting polymer, illustrating the versatility and wide applicability of the method. 相似文献
65.
Maikel León Lusine Mkrtchyan Benoît Depaire Da Ruan Koen Vanhoof 《Knowledge and Information Systems》2014,39(2):435-462
In modern society, more and more attention is given to the increase in public transportation or bike use. In this regard, one of the most important issues is to find and analyse the factors influencing car dependency and the attitudes of people in terms of preferred transport mode. Although the individuals’ transport behavioural modelling is a complex task, it has a notable social and economic impact. Thus, in this paper, fuzzy cognitive maps are explored to represent the behaviour and operation of such complex systems. This soft-computing technique allows modelling how the travellers make decisions based on their knowledge of different transport modes properties at different levels of abstraction. These levels correspond to the hierarchy perception including different scenarios of travelling, different benefits of choosing a specific travel mode, and different situations and attributes related to those benefits. We use learning and clustering of fuzzy cognitive maps to describe travellers’ behaviour and change trends in different abstraction levels. Cluster estimations are done before and after the learning of the maps, in order to compare people’s way of thinking if only considering an initial view of a transport mode decision for a daily activity, and when they really have a deeper reasoning process in view of benefits and consequences. The results of this study will help transportation policy decision makers in better understanding of people’s needs and consequently will help them actualizing different policy formulations and implementations. 相似文献
66.
Michael Filhol Mohamed N. Hadjadj Benoît Testu 《Universal Access in the Information Society》2016,15(4):487-498
The topic of this paper is machine translation (MT) from French text into French sign language (LSF). After arguing in favour of a rule-based method, it presents the architecture of an original MT system, built on two distinct efforts: formalising LSF production rules and triggering them with text processing. The former is made without any concern for text or translation and involves corpus analysis to link LSF form features to linguistic functions. It produces a set of production rules which may constitute a full LSF production grammar. The latter is an information extraction task from text, broken down in as many subtasks as there are rules in the grammar. After discussing this architecture, comparing it to the traditional methods and presenting the methodology for each task, the paper present the set of production rules found to govern event precedence and duration in LSF and gives a progress report on the implementation of the rule triggering system. With this proposal, it is also hoped to show how MT can benefit today from sign language processing. 相似文献
67.
Tilman Voigt Benoît Zuber Gerlinde Gawatz Gudrun Herrmann 《Microscopy research and technique》2013,76(7):679-686
In the long run, the widespread use of slide scanners by pathologists requires an adaptation of teaching methods in histology and cytology in order to target these new possibilities of image processing and presentation via the internet. Accordingly, we were looking for a tool with the possibility to teach microscopic anatomy, histology, and cytology of tissue samples which would be able to combine image data from light and electron microscopes independently of microscope suppliers. With the example of a section through the villus of jejunum, we describe here how to process image data from light and electron microscopes in order to get one image‐stack which allows a correlation of structures from the microscopic anatomic to the cytological level. With commercially available image‐presentation software that we adapted to our needs, we present here a platform which allows for the presentation of this new but also of older material independently of microscope suppliers. Microsc. Res. Tech. 76:679–686, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
68.
Billen G Garnier J Némery J Sebilo M Sferratore A Barles S Benoit P Benoît M 《The Science of the total environment》2007,375(1-3):80-97
A model (the Riverstrahler model) is used to describe nutrient transfer and transformation at the scale of the whole drainage network of the Seine based on information concerning the basic mechanisms governing N, P and Si inputs to the drainage network and in-stream transformation and retention. It was used to calculate the budget of these nutrients through the whole river continuum from land to sea. With the help of historical documents, the constraints used as forcing function in this model were reconstructed to express the changing conditions of land-use and urban population over the last five hundred years. The corresponding scenarios were run for different hydrological regimes including dry, mean and wet conditions. The results were validated on the long-term series of nutrient measurements spanning more than a century available at some stations on the Seine, upstream and downstream of the city of Paris. The model was also used to explore past and future trends in nutrient loading, retention and delivery to the coastal zone, in response to human management of the terrestrial watershed. Beside the initial pristine state, used as an idealized reference state (with N, P and Si delivered fluxes of about 45-110 kg N km(-2) yr(-1), 2-5 kg P km(-2) yr(-1), 510-1325 kg Si km(-2) yr(-1)), four periods were distinguished. The first one is that of the traditional cottage economy which prevailed, with quite a constant total population, until the end of the 18th century. N, P and Si fluxes were about 235-750 kg N km(-2) yr(-1), 15-60 kg P km(-2) yr(-1) and 425-1280 kg Si km(-2) yr(-1), depending on hydrological conditions. The second period, from the beginning of the 19th century to about the 1950's, corresponded to rapid increase in the total and urban population with a corresponding increase of point sources of N and P. From 1950 onwards, modern farming practices resulted in a dramatic increase in diffuse sources of nitrogen and to a lesser extent phosphorus: riverine N and P export reached 1320-2800 kg N km(-2) yr(-1), and 310-340 kg P km(-2) yr(-1): silica export remained fairly constant at around 410-1260 kg Si km(-2) yr(-1) depending on the hydrological conditions. In the 1990's, the fourth period is represented by a stabilized population and improved wastewater treatment, when the export of phosphorus is reduced to values as low as 40-60 kg P km(-2) yr(-1), but without as effective a reduction of nitrogen export. This represents an unprecedented situation for the marine coastal system, i.e. a shift from nitrogen to phosphorus limitation, as nitrogen is still delivered far in excess of the amount of silica available for diatom blooms. 相似文献
69.
Zitek Emily M.; Jordan Alexander H.; Monin Beno?t; Leach Frederick R. 《Canadian Metallurgical Quarterly》2010,98(2):245
Three experiments demonstrated that feeling wronged leads to a sense of entitlement and to selfish behavior. In Experiment 1, participants instructed to recall a time when their lives were unfair were more likely to refuse to help the experimenter with a supplementary task than were participants who recalled a time when they were bored. In Experiment 2, the same manipulation increased intentions to engage in a number of selfish behaviors, and this effect was mediated by self-reported entitlement to obtain positive (and avoid negative) outcomes. In Experiment 3, participants who lost at a computer game for an unfair reason (a glitch in the program) requested a more selfish money allocation for a future task than did participants who lost the game for a fair reason, and this effect was again mediated by entitlement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Benoît Mazères Clara Desgranges Caroline Toffolon-Masclet Daniel Monceau 《Oxidation of Metals》2013,79(1-2):121-133
Previous studies have shown that the numerical model EKINOX-Zr was able to simulate with accuracy oxide growth and oxygen diffusion into the matrix during high-temperature oxidation of Zy-4. In this study, the aim of the development was to evaluate if the observed effect of hydrogen cladding content on the increase of oxygen solubility in the high-temperature βZr was only a thermodynamic effect. Previous experimental studies have shown that hydrogen induces an evolution of equilibrium oxygen concentration at the αZr/βZr interface. The present work showed that EKINOX-Zr linked with the thermodynamic database Zircobase reproduced the evolution induced by hydrogen during the high-temperature steam oxidation. However, the results showed also that additional studies are necessary to better understand hydrogen behavior during high-temperature oxidation of Zr. 相似文献