Search results for "UAS"
showing 10 items of 1619 documents
Integrated plasmonic waveguides: A mode solver based on density of states formulation
2009
International audience; We express the density of states (DOS) near guided resonances of plasmonic waveguides by using multiple-scattering theory. In direct analogy with the case of localized electronic defect states in condensed matter, we demonstrate that optical DOS variations follow a lorentzian profile near guided modes resonances. The lorentzian shape gives quantitative information on the guided modes (effective index, propagation length, and polarization state). We numerically investigate both leaky and bound (lossy) modes supported by dielectric-loaded surface-plasmon-polariton waveguides.
FLIGHT CONTROL RESEARCH LABORATORY UNMANNED AERIAL SYSTEM WIND SHEAR ON-LINE IDENTIFICATION
2013
An algorithm to perform the on line identification of the wind shear components suitable for the UAS characteristics has been implemented. The mathematical model of aircraft and wind shear in the augmented state space has been built without any restrictive assumption on the dynamic of wind shear. Because of the strong velocity variations typical of wind shear induce severe accelerations on the aircraft the wind shear effects have been modeled as external forces and moments applied on the aircraft. The identification problem addressed in this work has been solved by using the Filter error method approach. An Extended Kalman Filter has been developed to propagate state. It has been tuned by u…
The sicilian cooperative system of wine production: the strategic choices and performance analyses of a case study
2020
Purpose The purpose of this paper is to verify whether, besides the traditional organisational models mainly implemented by wine-making cooperatives, more modern and hybrid organisational forms can be profitably applied within an increasingly competitive wine market. Design/methodology/approach The study outlined in this paper deployed a mixed method. Specifically, an archived analysis, a survey and a descriptive case study (including visits, interviews and documentary analysis) were the methodological techniques used in this study, which were “in series but integrated” between themselves. In this paper, the landscape of Sicilian wine cooperatives is described by collating and processing d…
Overdispersion tests in count-data analysis.
2008
Count data are commonly assumed to have a Poisson distribution, especially when there is no diagnostic procedure for checking this assumption. However, count data rarely fit the restrictive assumptions of the Poisson distribution. The violation of much of such assumptions commonly results in overdispersion, which invalidates the Poisson distribution. Undetected overdispersion may entail important misleading inferences, so its detection is essential. In this study, different overdispersion diagnostic tests are evaluated through two simulation studies. In Exp. 1, the nominal error rate is compared under different sample sizes and Λ conditions. Analysis shows a remarkable performance of the χ…
Nouvelles données sur la localité type et la morphométrie dentaire du campagnol de Gerbe Microtus pyrenaicus gerbei (Gerbe, 1879) (Cricetidae, Rodent…
2015
New data on type locality and dental morphometry of the Gerbe’s vole Microtus pyrenaicus gerbei (Gerbe, 1879) (Cricetidae, Rodentia). The synthesis of the historical research done on Arthur de L’Isle du Dréneuf’s life, the discoverer of the Gerbe’s vole Microtus pyrenaicus gerbei (Gerbe, 1879), and the circumstances connected with this discovery, allow to say that its type locality is the municipality of La Haie-Fouassière (Loire-Atlantique, France). The analysis of teeth found in pellets of barn owl from Pornic (Loire-Atlantique, France) has confirmed the odontometrical differentiation previously observed in M. pyrenaicus gerbei.
Lossless and nearly-lossless image compression based on combinatorial transforms
2011
Common image compression standards are usually based on frequency transform such as Discrete Cosine Transform or Wavelets. We present a different approach for loss-less image compression, it is based on combinatorial transform. The main transform is Burrows Wheeler Transform (BWT) which tends to reorder symbols according to their following context. It becomes a promising compression approach based on contextmodelling. BWT was initially applied for text compression software such as BZIP2 ; nevertheless it has been recently applied to the image compression field. Compression scheme based on Burrows Wheeler Transform is usually lossless ; therefore we imple-ment this algorithm in medical imagi…
Quantifier elimination in the quasi-analytic framework
2012
We associate to every compact polydisk B [belonging to ] Rn an algebra CB of real functions defined in a neighborhood of B. The collection of these algebras is supposed to be closed under several operations, such as composition and partial derivatives. Moreover, if the center of B is the origin, we assume that the algebra of germs at the origin of elements of CB is quasianalytic (it does not contain any flat germ). We define with these functions the collection of C-semianalytic and C-subanalytic sets according to the classical process in real analytic geometry. Our main result is an analogue of Tarski-Seidenberg's usual result for these sets. It says that the sub-C-subanalytic sets may be d…
Le cône diamant
2010
The diamond cone was introduced by N. J. Wildberger for the Lie algebra sl(n;R). It is a combinatoric presentation for the space C[N] of polynomials functions on the nilpotent factor N in the Iwasawa decomposition of SL(n;R). This presentation describes the natural layering of this indecomposable N-module. This basis can be indexeded by using some semi standard Young tableaux. We realize the algebra C[N] as a quotient of the shape algebra S_ for SL(n;R). Let us call reduced shape algebra this quotient. It is possible to select a family of semi standard Young tableaux, the quasi standard tableaux, in such a manner to get a basis for the reduced shape algebra. In the present thesis, this cons…
γ-RAY AND PARSEC-SCALE JET PROPERTIES OF A COMPLETE SAMPLE OF BLAZARS FROM THE MOJAVE PROGRAM
2011
著者人数: 145名
Collective excitations of 3He clusters
1991
Collective excitations of3He clusters are studied by treating the cluster as a quantum liquid drop. We have used the Random-Phase Approximation sum rules technique within a Density Functional Formalism. Results forL=2 to 10 surface modes and theL=0 volume mode are presented.