Search results for "Measurement"
showing 10 items of 2918 documents
Application of a radiative cooling model to daily minimum temperature prediction
1985
A model of exponential decrease of temperature is applied to the study of night cooling in an agricultural area of citrus orchards located near the Valentian Coast (Spain). A set of annual average parameters which determine that cooling is obtained by using temperature measurements at different levels during two years. These parameters appear to be representative of the thermal behaviour of the area of study. The attainment of such parameters allows a prediction of the minimum temperatures of the area to an accuracy of £1.5 K, knowing the temperature at sunset and some time later.
Wavelet analysis and neural network classifiers to detect mid-sagittal sections for nuchal translucency measurement
2016
We propose a methodology to support the physician in the automatic identification of mid-sagittal sections of the fetus in ultrasound videos acquired during the first trimester of pregnancy. A good mid-sagittal section is a key requirement to make the correct measurement of nuchal translucency which is one of the main marker for screening of chromosomal defects such as trisomy 13, 18 and 21. NT measurement is beyond the scope of this article. The proposed methodology is mainly based on wavelet analysis and neural network classifiers to detect the jawbone and on radial symmetry analysis to detect the choroid plexus. Those steps allow to identify the frames which represent correct mid-sagitta…
Charge carrier transport mechanisms in CdZnTe detectors grown by the vertical Bridgman technique
2016
In this work, we report on the results of electrical characterization of CdZnTe (CZT) detectors, with gold electroless contacts, grown by the boron oxide encapsulated vertical Bridgman technique (B-VB), currently produced at IMEM-CNR (Parma, Italy). The detectors, with different thicknesses (1 and 2.5 mm), have the same electrode layout: the anode is a central electrode (2 x 2 mm(2)) surrounded by a guard ring electrode. The cathode is a planar electrode covering the detector surface (4.1 x 4.1 mm(2)). Current-voltage (I-V) characteristics were measured at different temperatures in order to study the charge transport and the electrical properties. These detectors were compared with the trav…
Emissitivity spectra obtained from field and laboratory measurements using the temperature and emissivity separation algorithm.
2006
Surface emissivities play an important role in thermal remote sensing, since knowledge of them is required to estimate land surface temperature with enough accuracy. They are also important in other environmental or geological studies. We show the results obtained for the emissivity spectra of different natural surfaces (water, green, and senescent vegetation) by applying the temperature and emissivity separation (TES) algorithm to ground-based measurements collected at the field with a multiband thermal radiometer. The results have been tested with data included in spectral libraries, and rms errors lower than 0.01 have been found, except for senescent vegetation. Two methods are also prop…
A Bayesian approach to assess data from radionuclide activity analyses in environmental samples
2007
A Bayesian statistical approach is introduced to assess experimental data from the analyses of radionuclide activity concentration in environmental samples (low activities). A theoretical model has been developed that allows the use of known prior information about the value of the measurand (activity), together with the experimental value determined through the measurement. The model has been applied to data of the Inter-laboratory Proficiency Test organised periodically among Spanish environmental radioactivity laboratories that are producing the radiochemical results for the Spanish radioactive monitoring network. A global improvement of laboratories performance is produced when this pri…
Effects of radiation and hydrogen-loading on the performances of raman-distributed temperature fiber sensors
2015
International audience; The integration of Raman-distributed temperature fiber-based sensors (RDTS) into the envisioned French deep geological repository for nuclear wastes, called Cigéo requires evaluating how the performances of RDTS evolve in harsh environments, more precisely in presence of H2 or γ-rays. Both H2 and radiations are shown to affect the temperature measurements made with the single-ended RDTS technology. The amplitudes of the observed effects depend on the different classes of multimode fibers varying in terms of composition and coatings. By selecting the most tolerant fiber structure for the sensing, we could maintain the RDTS performances for such application. A hardeni…
Spin crossover behavior under pressure of Fe(PM-L)2(NCS)2 compounds with substituted 2′-pyridylmethylene 4-anilino ligands
1998
Abstract New iron(II) spin crossover systems with large aromatic ligands, based on 2′-pyridylmethylene 4-anilino units, have been synthesized and studied. The whole range of spin crossover behavior has been observed, starting from pure high-spin to more or less complete gradual transitions and finally to discontinuous type transitions with both small and large hysteresis. Magnetic measurements under pressure have revealed that two of the compounds exhibit pressure-induced new phases with larger hysteresis than at atmospheric pressure. For one of the compounds the formation of this new phase is irreversible and the hysteresis width is ∼100 K, as compared to 37 K before applying pressure.
Toward more realistic viscosity measurements of tyre rubber–bitumen blends
2014
AbstractThe measurement of rheological properties of the tyre rubber bitumen blends is often challenging due to presence of suspended tyre rubber’s crumbs. Furthermore, the phase separation during the course of measurements makes the viscosity of these non-homogeneous blends difficult to ascertain. In this study, a new dual helical impeller was designed and manufactured to be used with a rotational viscometer in order to have a real-time control of the viscosity while performing a laboratory mixing of the blends. Layer based manufacturing techniques showed to be a convenient method to produce complex shaped impeller prototypes before manufacturing the more expensive stainless steel assembly…
An automatic filtering algorithm for SURF-based registration of remote sensing images
2017
International audience; The registration of remote sensing images has been often a necessary step for further analyses of images taken at different times, different viewing geometry or with different sensors. For this task there exists many approaches. This paper focuses on the feature-based category of image registration methods. Particularly, we propose an improvement of the SURF algorithm on the point matching step. Indeed, in order to achieve a correct registration, a good matching of feature point is required. However The presence of outliers lead to a fail in the registration. Therefore, in this paper, we introduce an efficient method devoted to the detection and removal of such outli…
The stigma of low opioid prescription in the hospitalized multimorbid elderly in Italy.
2015
The primary aim of this study was to evaluate the prevalence of opioid prescriptions in hospitalized geriatric patients. Other aims were to evaluate factors associated with opioid prescription, and whether or not there was consistency between the presence of pain and prescription. Opioid prescriptions were gathered from the REgistro POliterapie Societa` Italiana di Medicina Interna (REPOSI) data for the years 2008, 2010 and 2012. 1,380 in-patients, 65+ years old, were enrolled in the first registry run, 1,332 in the second and 1,340 in the third. The prevalence of opioid prescription was calculated at hospital admission and discharge. In the third run of the registry, the degree of pain was…