Vienna University of Technology

About: Vienna University of Technology is a education organization based out in Vienna, Austria. It is known for research contribution in the topics: Laser & Context (language use). The organization has 16723 authors who have published 49341 publications receiving 1302168 citations.

Skill and Global Trend Analysis of Soil Moisture from Reanalyses and Microwave Remote Sensing

Abstract: In situ soil moisture measurements from 2007 to 2010 for 196 stations from five networks across the world (United States, France, Spain, China, and Australia) are used to determine the reliability of three soil moisture products: (i) a revised version of the ECMWF Interim Re-Analysis (ERA-Interim; ERA-Land); (ii) a revised version of the Modern-Era Retrospective Analysis for Research and Applications (MERRA) reanalysis from NASA (MERRA-Land); and (iii) a new, microwave-based multisatellite surface soil moisture dataset (SM-MW). Evaluation of the time series and anomalies from a moving monthly mean shows a good performance of the three products in capturing the annual cycle of surface soil moisture and its short-term variability. On average, correlations (95% confidence interval) are 0.66 (±0.038), 0.69 (±0.038), and 0.60 (±0.061) for ERA-Land, MERRA-Land, and SM-MW. The two reanalysis products also capture the root-zone soil moisture well; on average, correlations are 0.68 (±0.035) and 0.73 (±0.03...

Development and experimental validation of a continuum micromechanics model for the elasticity of wood

Abstract: This contribution covers the development and validation of a microelastic model for wood, based on a four-step homogenization scheme At a length scale of several tens of nanometers, hemicellulose, lignin, and water are intimately mixed, and build up a polymer (polycrystal-type) network At a length scale of around one micron, fiberlike aggregates of crystalline and amorphous cellulose are embedded in an contiguous polymer matrix, constituting the so-called cell wall material At a length scale of about one hundred microns, the material softwood is defined, comprising cylindrical pores (lumen) in the cell wall material of the preceding homogenization step Finally, at a length scale of several millimeters, hardwood comprises larger cylindrical pores (vessels) embedded in the softwood-type material homogenized before Model validation rests on statistically and physically independent experiments: The macroscopic stiffness values (of hardwood or softwood) predicted by the micromechanical model on the basis of tissue-independent (‘universal’) phase stiffness properties of hemicellulose, amorphous cellulose, crystalline cellulose, lignin, and water (experimental set I) for tissue-specific composition data (experimental set IIb) are compared to corresponding experimentally determined tissue-specific stiffness values (experimental set IIa)

Biomass gasification for synthesis gas production and applications of the syngas

Abstract: Synthesis gas from biomass can be produced and utilized in different ways. Conversion of biomass to synthesis gas can be done either in fluidized bed or entrained flow reactors. As gasification agent oxygen, steam, or mixtures are used. The most common use of biomass gasification in the last decades has been for heat and/or power production. Nowadays, the importance of transportation fuels from renewables is increased due to environmental aspects and growing fossil fuels prices. That is why the production of Fischer‐Tropsch (FT) liquids, methanol, mixedalcohols,substitutenaturalgas(SNG),andhydrogenfrombiomassisnowin focus of view. The most innovative and interesting ways of synthesis gas utilization andprojects,BioTfueLorGoBiGas,BioLiq,Choren,etc.arediscussedhere.Further the microchannel technology by Oxford Catalysts and distributed production of SNG in decentral small scale are presented. The synthesis platform in G¨ ussing, Austria is also presented. The FT liquids, hydrogen production, mixed alcohols, and BioSNG, these are the projects associated with the FICFB gasification plant in G¨ ussing. Also the principle and examples of sorption-enhanced reforming to adjust H2/CO ratio in product gas during the gasification is described. Finally, in the conclusion also an outlook for the thermochemical pathway to transportation fuels is given. © 2013 John Wiley & Sons, Ltd.

Search for the associated production of the Higgs boson with a top-quark pair

Abstract: A search for the standard model Higgs boson produced in association with a top-quark pair (ttH) is presented, using data samples corresponding to integrated luminosities of up to 5.1 fb^(−1) and 19.7 fb^(−1) collected in pp collisions at center-of-mass energies of 7 TeV and 8 TeV respectively. The search is based on the following signatures of the Higgs boson decay: H → hadrons, H → photons, and H → leptons. The results are characterized by an observed ttH signal strength relative to the standard model cross section, μ=σ/σ SM,under the assumption that the Higgs boson decays as expected in the standard model. The best fit value is μ = 2.8 ± 1.0 for a Higgs boson mass of 125.6 GeV.