MAPPING DECIDUOUS FORESTS BY USING TIME SERIES OF FILTERED MODIS NDVI AND NEURAL NETWORKS

Multi-temporal images are now of standard use in remote sensing of vegetation during monitoring and classification. Temporal vegetation signatures (i. e., vegetation indices as functions of time) generated, poses many challenges, primarily due to signal to noise-related issues. This study investigates which methods generate the most appropriate smoothed curves of vegetation signatures on MODIS NDVI time series. The filtering techniques compared were the HANTS algorithm which is based on Fourier analyses and Wavelet temporal algorithm which uses the wavelet analysis to generate the smoothed curves. The study was conducted in four different regions of the Minas Gerais State. The smoothed data were used as input data vectors for vegetation classification by means of artificial neural networks for comparison purpose. A comparison of the results was ultimately discussed in this work showing encouraging results and similarity between the two filtering techniques used.16212313

Sliding Wear Behavior of Al2O3-TiO2 Coatings Fabricated by the Suspension Plasma Spraying Technique

[EN] The friction and dry sliding wear behavior of alumina and alumina-titania near-nanometric coatings were examined. Coatings were obtained by the suspension plasma spraying technique. Dry sliding wear tests were performed on a ball-on-disk tribometer, with an Al2O3 ball as counterpart material, a normal load of 2 N, a sliding distance of 1200 m and a sliding speed of 0.1 m/s. The effect of including TiO2 in the fabricated coatings on friction coefficient behavior, wear rates and wear damage patterns was determined. The addition of TiO2 to the coatings was found to greatly increase wear resistance by, for example, 2.6-fold for 40 wt% of TiO2. The analysis of the wear surface was correlated with microstructural parameters, mechanical properties and wear rates.The authors wish to thank for the Spanish Ministry of Economy and Competitiveness (MAT2012-38364-C03) and the Autonomous Government of Valencia for funding for the stay in SPCTS-UMR CNRS (France), and the French FCENANOSURF consortium funded by the French Ministry and Industry and local governments of Region Centre and Region Limousin.Klyatskina, E.; Espinosa Fernández, L.; Darut, G.; Segovia López, EF.; Salvador Moya, MD.; Montavon, G.; Agorges, H. (2015). Sliding Wear Behavior of Al2O3-TiO2 Coatings Fabricated by the Suspension Plasma Spraying Technique. Tribology Letters. 59(1):1-9. https://doi.org/10.1007/s11249-015-0530-5S19591Pawlowski, L.: The Science and Engineering of Thermal Spray Coatings. Wiley: Hoboken (2008)Lampe, Th, Eisenberg, S., Cabeo, E.R.: Plasma surface engineering in the automotive industry—trends and future prospective. Surf. Coat. Technol. 174–175, 1–7 (2003)Wang, Y., Jiang, S., Wang, M., Wang, S., Xiao, T.D., Strutt, P.R.: Abrasive wear characteristics of plasma sprayed nanostructured alumina/titania coatings. Wear 237, 176–185 (2000)Kabacoff, L.T.: Nanoceramic coatings exhibit much higher toughness and wear resistance than conventional coatings. AMPITAC Newslett. 6(1), 37–42 (2002)Wang, M., Shaw, L.L.: Effects of the powder manufacturing method on microstructure and wear performance of plasma sprayed alumina–titania coatings. Surf. Coat. Technol. 202, 34–44 (2007)Shaw, L.L., Goberman, D., Ren, R., Gell, M., Jing, S., Wang, Y., Xiao, T.D., Strutt, P.R.: The dependency of microstructure and properties of nanostructured coatings on plasma spray conditions. Surf. Coat. Technol. 130, 1–8 (2000)Dahotre, N.B., Nayak, S.: Nanocoatings for engine application. Surf. Coat. Technol. 194(1), 58–67 (2005)Sathish, S., Geetha, M., Aruna, S.T., Balaji, N., Rajam, K.S., Asokamani, R.: Sliding wear behavior of plasma sprayed nanoceramic coatings for biomedical applications. Wear 271, 934–941 (2011)Pawlowski, L.: Finely grained nanometric and submicrometric coatings by thermal sparing: a review. Surf. Coat. Technol. 202, 4318–4328 (2008)Xiao, D., Wang, Y., Strutt, P.: Fabrication and evaluation of plasma sprayed nanostructured alumina–titania coatings with superior properties. Mater. Sci. Eng. 301, 80–89 (2001)Tjong, S.C., Chen, H.: Nanocrystalline materials and coatings. Mater. Sci. Eng. 45, 1–88 (2004)Fauchais, P., Montavon, G., Bertrand, G.: From powders to thermally sprayed coatings. J. Therm. Spray Technol. 19, 56–80 (2010)Lima, R.S., Marple, B.R.: Thermal spray coatings engineered from nanostructured ceramic agglomerated powders for structural, thermal barrier and biomedical applications: a review. J. Therm. Spray Technol. 16, 40–63 (2007)Fauchais, P., Etchart-Salas, R., Delbos, C., Tognonvi, M., Rat, V., Coudert, J.F., Chartier, T.: Suspension and solution plasma spraying of finely structured layers: potential application to SOFCs. J. Phys. D Appl. Phys. 40, 2394–2406 (2007)Ramachandran, K., Selvajaran, V., Ananthapadmanabhan, P.V., Sreekumar, K.P.: Microstructure, adhesion, micro hardness, abrasive wear resistance and electrical resistivity of the plasma sprayed alumina and alumina–titania coatings. Thin Solid Films 315, 144–152 (1998)Lee, S.W., Morillo, C., Lira-Olivares, J., Kim, S.H., Sekino, T., Niihara, K., Hockey, B.J.: Tribological and microstructural analysis of Al2O3/13TiO2 nanocomposites to use in femoral head of hip replacement. Wear 225, 1040–1044 (2003)Dejang, N., Watcharapasorn, A., Wirojupatump, S., Niranatlumpong, P., Jiansirisomboon, S.: Fabrication and properties of plasma-sprayed Al2O3/TiO2 composite coatings: a role of nano-sized TiO2 addition. Surf. Coat. Technol. 204, 1651–1657 (2010)Yimaz, S.: An evaluation of plasma sprayed coatings based on Al2O3 and Al2O3–13wt% TiO2 with bond coat on pure titanium substrate. Ceram. Int. 35, 2017–2022 (2009)Fervel, V., Normand, B., Coddet, C.: Tribological behavior of plasma sprayed Al2O3-based cermet coatings. Wear 230(1), 70–77 (1999)Vargas, F., Ageorges, H., Fauchais, P., López, M.E.: Mechanical and a tribological performance of Al2O3 coatings elaborated by flame and plasma spraying. Surf. Coat. Technol. 205, 1132–1136 (2010)Bacciochini, A., Ilavsky, J., Montavon, G., Denoirjean, A., Ben-ettouil, F., Valette, S., Fauchais, P., Wittmann-teneze, K.: Quantification of void network architectures of suspension plasma-sprayed (SPS) yttria-stabilized zirconia (YSZ) coatings using ultra-small-angle X-ray scattering (USAXS). Mater. Sci. Eng. 528, 91–102 (2010)ASTM International: ASTM G99-03: Standard test method for wear testing with a pin-on-disc apparatus. ASTM annual book of standards. ASTM International: West Conshohocken (2003)Lancaster, K.: The influence of substrate hardness on the formation and endurance of molybdenum disulphide films. Wear 10, 103–107 (1967)Fauchais, P., Rat, V., Delbos, C., Fazilleau, J., Coudert, J.F., Chartier, T., Bianchi, L.: Understanding of suspension plasma spraying of finely structured coatings for SOFC. IEEE Plasma Sci. 33(2), 920–930 (2005)Bannier, E., Vicent, M., Rayón, E., Benavente, R., Salvador, M.D., Sánchez, E.: Effect of TiO2 addition on the microstructure and nanomechanical properties of Al2O3 suspension plasma sprayed coatings. Appl. Surf. Sci. 316, 141–146 (2014)Darut, G., Klyatskina, E., Valette, S., Carles, P., Denoirjean, A., Montavon, G., Ageorges, H., Segovia, F., Salvador, M.D.: Architecture and phases composition of suspension plasma sprayed alumina–titania sub-micrometer-sized coatings. Mater. Lett. 67, 241–244 (2012)Fauchais, P., Montavon, G.: Latest developments in suspension and liquid precursor thermal spraying. J. Therm. Spray Technol. 19(1–2), 226–239 (2010)Darut, G., Ben-Ettouli, F., Denoirjean, A., Montavon, G., Ageourges, H., Fauchais, P.: Dry sliding behavior of sub-micrometer-sized suspension plasma sprayed ceramic oxide coatings. J. Therm. Spray Technol. 19, 275–285 (2010)Tingaud, O., Bacciochini, A., Montavon, G., Denoirjean, A., Fauchais, P.: Suspension DC plasma spraying of thick finely-structured ceramic coatings: process manufacturing mechanisms. Surf. Coat. Technol. 203, 2157–2161 (2009)Guesama, S., Bounazef, M., Nardin, P., Sahraoui, T.: Wear behavior of alumina–titania coatings: analysis of process and parameters. Ceram. Int. 32, 13–19 (2006)Espinosa-Fernández, L., Borrell, A., Salvador, M.D., Gutierrez-Gonzalez, C.F.: Sliding wear behavior of WC–Co–Cr3C2–VC composites fabricated by conventional and non-conventional techniques. 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Limits on WWZ and WW\gamma couplings from p\bar{p}\to e\nu jj X events at \sqrt{s} = 1.8 TeV

We present limits on anomalous WWZ and WW-gamma couplings from a search for WW and WZ production in p-bar p collisions at sqrt(s)=1.8 TeV. We use p-bar p -> e-nu jjX events recorded with the D0 detector at the Fermilab Tevatron Collider during the 1992-1995 run. The data sample corresponds to an integrated luminosity of 96.0+-5.1 pb^(-1). Assuming identical WWZ and WW-gamma coupling parameters, the 95% CL limits on the CP-conserving couplings are -0.33<lambda<0.36 (Delta-kappa=0) and -0.43<Delta-kappa<0.59 (lambda=0), for a form factor scale Lambda = 2.0 TeV. Limits based on other assumptions are also presented.Comment: 11 pages, 2 figures, 2 table

Search for New Physics in e mu X Data at D0 Using Sleuth: A Quasi-Model-Independent Search Strategy for New Physics

We present a quasi-model-independent search for the physics responsible for electroweak symmetry breaking. We define final states to be studied, and construct a rule that identifies a set of relevant variables for any particular final state. A new algorithm ("Sleuth") searches for regions of excess in those variables and quantifies the significance of any detected excess. After demonstrating the sensitivity of the method, we apply it to the semi-inclusive channel e mu X collected in 108 pb^-1 of ppbar collisions at sqrt(s) = 1.8 TeV at the D0 experiment during 1992-1996 at the Fermilab Tevatron. We find no evidence of new high p_T physics in this sample.Comment: 23 pages, 12 figures. Submitted to Physical Review

Search For Heavy Pointlike Dirac Monopoles

We have searched for central production of a pair of photons with high transverse energies in $p\bar p$ collisions at $\sqrt{s} = 1.8$ TeV using $70 pb^{-1}$ of data collected with the D\O detector at the Fermilab Tevatron in 1994--1996. If they exist, virtual heavy pointlike Dirac monopoles could rescatter pairs of nearly real photons into this final state via a box diagram. We observe no excess of events above background, and set lower 95% C.L. limits of $610, 870, or 1580 GeV/c^2$ on the mass of a spin 0, 1/2, or 1 Dirac monopole.Comment: 12 pages, 4 figure

The Dijet Mass Spectrum and a Search for Quark Compositeness in bar{p}p Collisions at sqrt{s} = 1.8 TeV

Using the DZero detector at the 1.8 TeV pbarp Fermilab Tevatron collider, we have measured the inclusive dijet mass spectrum in the central pseudorapidity region |eta_jet| < 1.0 for dijet masses greater than 200 Gev/c^2. We have also measured the ratio of spectra sigma(|eta_jet| < 0.5)/sigma(0.5 < |eta_jet| < 1.0). The order alpha_s^3 QCD predictions are in good agreement with the data and we rule out models of quark compositeness with a contact interaction scale < 2.4 TeV at the 95% confidence level.Comment: 11 pages, 4 figures, 2 tables, submitted to Phys. Rev. Let

Search for High Mass Photon Pairs in p-pbar --> gamma-gamma-jet-jet Events at sqrt(s)=1.8 TeV

A search has been carried out for events in the channel p-barp --> gamma gamma jet jet. Such a signature can characterize the production of a non-standard Higgs boson together with a W or Z boson. We refer to this non-standard Higgs, having standard model couplings to vector bosons but no coupling to fermions, as a "bosonic Higgs." With the requirement of two high transverse energy photons and two jets, the diphoton mass (m(gamma gamma)) distribution is consistent with expected background. A 90(95)% C.L. upper limit on the cross section as a function of mass is calculated, ranging from 0.60(0.80) pb for m(gamma gamma) = 65 GeV/c^2 to 0.26(0.34) pb for m(gamma gamma) = 150 GeV/c^2, corresponding to a 95% C.L. lower limit on the mass of a bosonic Higgs of 78.5 GeV/c^2.Comment: 9 pages, 3 figures. Replacement has new H->gamma gamma branching ratios and corresponding new mass limit