Search results for "libration"
showing 10 items of 901 documents
A New Calibration Method for the Accurate Determination of Ethylene Content in Ethylene-Propylene Copolymers by CRYSTEX-IR
2012
Summary: CRYSTEX is a fully automated instrument for the determination of Xylene Solubles in polypropylene and ethylene-propylene copolymers, providing an excellent correlation with gravimetric methods. The instrument can be equipped with a dual band infrared (IR) detector to quantify the ethylene weight percentage (C2%) in the amorphous fraction, and in the whole polymer sample. In this work, a new approach based on multiple linear regression (MLR) models is presented, which makes use of two independent IR absorbance signals acquired simultaneously by the detector. A compromise model to predict directly C2% is proposed, which balances good accuracy and reduced experimental effort. MLR mode…
The positioning system of the ANTARES Neutrino Telescope
2012
The ANTARES neutrino telescope, located 40km off the coast of Toulon in the Mediterranean Sea at a mooring depth of about 2475m, consists of twelve detection lines equipped typically with 25 storeys. Every storey carries three optical modules that detect Cherenkov light induced by charged secondary particles (typically muons) coming from neutrino interactions. As these lines are flexible structures fixed to the sea bed and held taut by a buoy, sea currents cause the lines to move and the storeys to rotate. The knowledge of the position of the optical modules with a precision better than 10cm is essential for a good reconstruction of particle tracks. In this paper the ANTARES positioning sys…
Modelling biological and chemically induced precipitation of calcium phosphate in enhanced biological phosphorus removal systems
2011
The biologically induced precipitation processes can be important in wastewater treatment, in particular treating raw wastewater with high calcium concentration combined with Enhanced Biological Phosphorus Removal. Currently, there is little information and experience in modelling jointly biological and chemical processes. This paper presents a calcium phosphate precipitation model and its inclusion in the Activated Sludge Model No 2d (ASM2d). The proposed precipitation model considers that aqueous phase reactions quickly achieve the chemical equilibrium and that aqueous-solid change is kinetically governed. The model was calibrated using data from four experiments in a Sequencing Batch Rea…
Characterization of a Modified Expansion Condensation Particle Counter for Detection of Nanometer-Sized Particles
2009
A newly developed condensation particle counter provides measurements of aerosol particle number densities for size diameters as low as 3 nm. This Expansion Condensation Particle Counter (ECPC) operates based on fast adiabatic expansion with specialized detection and evaluation of the temporal development of light scattered by the ensemble of growing droplets. In its new configuration the ECPC has been modified such that a previously needed calibration factor became obsolete. In this article the new design is described which now includes a fast pressure sensor for monitoring the pressure drop inside the measurement chamber. Extensive laboratory experiments for characterizing the ECPC are de…
A practical protocol for calibration of nutrient removal wastewater treatment models
2011
Activated sludge models can be very useful for designing and managing wastewater treatment plants (WWTPs). However, as with every model, they need to be calibrated for correct and reliable application. Activated sludge model calibration is still a crucial point that needs appropriate guidance. Indeed, although calibration protocols have been developed, the model calibration still represents the main bottleneck to modelling. This paper presents a procedure for the calibration of an activated sludge model based on a comprehensive sensitivity analysis and a novel step-wise Monte Carlo-based calibration of the subset of influential parameters. In the proposed procedure the complex calibration i…
Standardisation of elemental analytical techniques applied to provenance studies of archaeological ceramics: an inter laboratory calibration studyEle…
2002
Chemical analysis is a well-established procedure for the provenancing of archaeological ceramics. Various analytical techniques are routinely used and large amounts of data have been accumulated so far in data banks. However, in order to exchange results obtained by different laboratories, the respective analytical procedures need to be tested in terms of their inter-comparability. In this study, the schemes of analysis used in four laboratories that are involved in archaeological pottery studies on a routine basis were compared. The techniques investigated were neutron activation analysis (NAA), X-ray fluorescence analysis (XRF), inductively coupled plasma optical emission spectrometry (I…
Towards the determination of isoprene in human breath using substrate-integrated hollow waveguide mid-infrared sensors
2014
Selected volatile organic compounds (VOCs) in breath may be considered biomarkers if they are indicative of distinct diseases or disease states. Given the inherent molecular selectivity of vibrational spectroscopy, infrared sensing technologies appear ideally suitable for the determination of endogenous VOCs in breath. The aim of this study was to determine that mid-infrared (MIR; 3-20 µm) gas phase sensing is capable of determining isoprene in exhaled breath as an exemplary medically relevant VOC by hyphenating novel substrate-integrated hollow waveguides (iHWG) with a likewise miniaturized preconcentration system. A compact preconcentrator column for sampling isoprene from exhaled breath …
Validation and update of the thoracic surgery scoring system (Thoracoscore) risk model.
2020
Abstract OBJECTIVES The performance of prediction models tends to deteriorate over time. The purpose of this study was to update the Thoracoscore risk prediction model with recent data from the Epithor nationwide thoracic surgery database. METHODS From January 2016 to December 2017, a total of 56 279 patients were operated on for mediastinal, pleural, chest wall or lung disease. We used 3 recommended methods to update the Thoracoscore prediction model and then proceeded to develop a new risk model. Thirty-day hospital mortality included patients who died within the first 30 days of the operation and those who died later during the same hospital stay. RESULTS We compared the baseline patient…
Measuring intrinsic thickness of rough membranes: application to nanofibrillated cellulose films
2015
Adequate measurement of thickness of sheet-like materials or membranes is most important for quantifying their properties such as density, barrier properties and mechanical strength. Depending on the surface roughness of the membrane, the thickness measured by standard micrometre devices (apparent thickness) may considerably overestimate the actual geometrical mean thickness (intrinsic thickness) required for such purposes. In this work, we present a method for correcting the measured apparent thickness value of thin membranes for their surface roughness, thereby obtaining an improved estimate of the intrinsic thickness. The surface roughness data required for the correction can be obtained…
Alignment for the first precision measurements at Belle II
2019
On March 25th 2019, the Belle II detector recorded the first collisions delivered by the SuperKEKB accelerator. This marked the beginning of the physics run with vertex detector. The vertex detector was aligned initially with cosmic ray tracks without magnetic field simultaneously with the drift chamber. The alignment method is based on Millepede II and the General Broken Lines track model and includes also the muon system or primary vertex position alignment. To control weak modes, we employ sensitive validation tools and various track samples can be used as alignment input, from straight cosmic tracks to mass-constrained decays. With increasing luminosity and experience, the alignment is …