Search results for "Calibration"
showing 10 items of 890 documents
Acoustic Scene Classification with Squeeze-Excitation Residual Networks
2020
Acoustic scene classification (ASC) is a problem related to the field of machine listening whose objective is to classify/tag an audio clip in a predefined label describing a scene location (e. g. park, airport, etc.). Many state-of-the-art solutions to ASC incorporate data augmentation techniques and model ensembles. However, considerable improvements can also be achieved only by modifying the architecture of convolutional neural networks (CNNs). In this work we propose two novel squeeze-excitation blocks to improve the accuracy of a CNN-based ASC framework based on residual learning. The main idea of squeeze-excitation blocks is to learn spatial and channel-wise feature maps independently…
Hyperspectral imaging of asteroids using an FPI-based sensor
2021
The compositions of asteroids are of interest for the planetary sciences, mining, and planetary defense. The main method for evaluating these compositions is reflectance spectroscopy. Spectroscopic measurements performed from Earth can not resolve how different materials are distributed on the asteroids, making flyby-- and rendezvous missions necessary for obtaining detailed information. Using the CubeSat platform could reduce the costs of these missions, but it also sets constraints on the payload mass and volume. One small and light instrument capable of producing spatially resolved spectral data is a hyperspectral imager based on the Fabry-Perot interferometer. We propose a method of cal…
Testing the X-IFU calibration requirements: an example for quantum efficiency and energy resolution
2018
With its array of 3840 Transition Edge Sensors (TESs) operated at 90 mK, the X-Ray Integral Field Unit (X-IFU) on board the ESA L2 mission Athena will provide spatially resolved high-resolution spectroscopy (2.5 eV FWHM up to 7 keV) over the 0.2 to 12 keV bandpass. The in-flight performance of the X-IFU will be strongly affected by the calibration of the instrument. Uncertainties in the knowledge of the overall system, from the filter transmission to the energy scale, may introduce systematic errors in the data, which could potentially compromise science objectives - notably those involving line characterisation e.g. turbulence velocity measurements - if not properly accounted for. Defining…
Hybrid chaotic firefly decision making model for Parkinson’s disease diagnosis
2020
Parkinson’s disease is found as a progressive neurodegenerative condition which affects motor circuit by the loss of up to 70% of dopaminergic neurons. Thus, diagnosing the early stages of incidence is of great importance. In this article, a novel chaos-based stochastic model is proposed by combining the characteristics of chaotic firefly algorithm with Kernel-based Naïve Bayes (KNB) algorithm for diagnosis of Parkinson’s disease at an early stage. The efficiency of the model is tested on a voice measurement dataset that is collected from “UC Irvine Machine Learning Repository.” The dynamics of chaos optimization algorithm will enhance the firefly algorithm by introducing six types of chao…
Study of mycotoxin calibration approaches on the example of trichothecenes analysis from flour
2012
The aim of this study was to evaluate the applicability of different calibration approaches in trichothecenes analysis from wheat flour. Concretely eight trichothecenes (five type B trichothecenes and three type A trichothecenes) were analyzed by matrix solid-phase dispersion (MSPD) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). In the first set of experiments the presence of matrix effects was evaluated; values ranged between 59% and 79%. In the second set of experiments, solutions to compensate these signal suppressions were examined. Different calibration methods showed to tackle matrix effects obtaining values between 69% and 85% for external matrix matched calibration a…
Flow-injection analysis study of the chemiluminescent behaviour of proflavine and acriflavine
2001
Abstract The chemiluminescent behaviour of the amino acridines like acriflavine, and proflavin is reported. Different strong oxidants (potassium permanganate, cerium(IV), hexacyanoferrate(III), hydrogen peroxide in different media) were tested, and potassium permanganate in sulphuric acid medium was selected. The study of the experimental parameters affecting the oxidation and detection was performed with the aid of a FIA assembly. The calibration graph was applied over the range 0.05–12.0 μg ml −1 of acriflavine (regression coefficient 0.9957, and the calculated relative standard deviation (R.S.D., %) was 0.9; LOD 10 ng ml −1 and the sample throughput 48 h −1 . The study of interfering com…
Determination of Amitriptyline with Bromocresol Purple and Flow Injection Analysis
1990
Abstract The study of some amitriptyline-dye systems was carried out in order to determine the best precipitate for the turbidimetric determination of amitriptyline using FIA. The reagent selected was bromocresol purple. The chemical and FIA variables were optimized. The calibration graph was linear over the concentration range 30.0–200.0 ppm of amitriptyline hydrochloride. Some interfering substances were also investigated.
FIA-fluorimetric determination of adrenaline by oxidation with a solid-phase reactor of manganese dioxide incorporated in polyester resin beads
1995
Abstract The FIA-spectrofluorimetric determination of adrenaline was carried out by reaction of the drug with manganese dioxide entrapped in a polymeric material in a solid-phase reactor; the oxidized drug was monitored fluorimetrically at 540 nm (Ioxg. 330.0 nm). The calibration graph for adrenaline was linear over the range 0.5 - 20 μg ml−1 with a relative standard deviation of 2.0% (at 5 ug ml−1) and the sample throughput of 65 h−1. The influence of foreign compounds was studied and the method was applied to the determination of adrenaline content in a pharmaceutical formulation . ∗Present address: Institut of Chemistry, Warsawa University, Bialystok Branch, Bialystok, Poland.
Determination of promethazine hydrochloride with bromophenol blue by a turbidimetric method and flow injection analysis
1992
Abstract A flow injection analysis procedure for the turbidimetric determination of promethazine is proposed. The sample solution is injected directly into the carrier reagent stream, which is composed of 1.16 × 10 −3 M bromophenol blue at pH 1.20. The calibration graph is linear over the range 25–197 ppm of promethazine. The influence of some foreign substances was also investigated. The method is applied to promethazine determination in a pharmaceutical formulation.
Cerium(IV) arsenite as a solid-phase reactor for use in flow-injection analysis. Spectrophotometric determination of promethazine
1992
Abstract Cerium(IV) arsenite is used as a strongly oxidizing solid-phase reactor in an unsegmented continuous-flow injection assembly. Its preparation procedure produces particles of uniform size with suitable physico-chemical properties for use in a continuous-flow system. A manifold is proposed for the determination of promethazine in pharmaceutical preparations by spectrophotometric monitoring of the red colour produced by the oxidized drug. A linear calibration graph is obtained over the range 5–400 μg ml −1 of promethazine.