211 research outputs found

    Taboo of alcohol and road safety policies in Algeria

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    The objective of this work is to show the real dimension of drunk driving in Algeria through the statistics of road accidents, the evolution of the legislative framework concerning driving while drunk and road preventive actions undertaken to fight against this risk factor. We first analyzed the statistics published by the National Centre for Road Safety (NCRS) in recent years to present the part of driving while drunk in the national data of road accidents. Then we retraced the evolution of the legislative framework for road safety particularly the laws governing driving while drunk. Finally, an overview of how the mass media process and disseminate information related to road traffic accidents, especially one devoted to driving while drunk and that has been achieved to show the part of the means of information in road safety. The results show that driving under the influence of alcohol is behind a significant number of road traffic accidents in Algeria. The results also show that the legislative framework concerning this risk is limited to the fixing of rates of blood alcohol concentrations authorized for driving. These same results reveal the absence of sensitization actions, information and research for this risk factor particular by the mass media. Driving while drunk is a real problem for road safety in Algeria which preserves an unclear representation in the society and constitutes a taboo subject which slows down road safety policies.Key words: Alcohol, driving while drunk, driving under influence of alcohol, road safety, Algeri

    Lidar observations of middle atmospheric gravity wave activity over a low-latitude site (Gadanki, 13.5° N, 79.2° E)

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    The low-latitude middle atmospheric gravity wave characteristics are presented using 310 nights of Rayleigh lidar observations made at Gadanki (13.5° N, 79.2° E) over the period from March 1998 to December 2002. The gravity wave characteristics are presented in terms of vertical wave number and frequency spectra, along with the estimated potential energy for the four seasons, namely, spring, summer, autumn and winter. The computed wave number spectra for both the stratosphere and the mesosphere are found to differ significantly from a saturated model predicted spectrum. The spectra were found to be shallower at lower wave numbers and steeper at higher wave numbers with transition at ~8.85×10-4 cy/m. The computed frequency spectra seem to follow the model plot with a power law index of -5/3 above a frequency of ~2×10-4 Hz. The estimated potential energy per unit mass increases gradually up to ~60 km and then rather rapidly above this height to reach values of the order of 200 J/kg at ~70 km

    Extracting gravity wave parameters during the September 2002 Southern Hemisphere major sudden stratospheric warming using a SANAE imaging riometer

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    Using absorption data measured by imaging riometer for ionospheric studies (IRIS) located at the South Africa National Antarctic Expedition (SANAE), Antarctica (72° S, 3° W), we extracted the parameters of gravity waves (GW) of periods between 40 and 50 min during late winter/spring of the year 2002, a period of the unprecedented major sudden stratospheric warming (SSW) in the Southern Hemisphere middle atmosphere. During this period, an unprecedented substantial increase of temperature by about 25–30 K throughout the stratosphere was observed. During the period of the occurrence of the major stratospheric warming, there was a reduction of both the GW horizontal phase speeds and the horizontal wavelengths at 90 km. The GW phase speeds and horizontal wavelengths were observed to reach minimum values of about 7 m s<sup>−1</sup> and 19 km, respectively, while during the quiet period the average value of the phase speed and horizontal wavelength was approximately 23 m s<sup>−1</sup> and 62 km, respectively. The observed event is discussed in terms of momentum flux and also a potential interaction of gravity waves, planetary waves and mean circulation

    Simulation and analysis of the forward bias current–voltage–temperature characteristics of W/4H-SiC Schottky barrier diodes for temperature-sensing applications

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    Abstract The current-voltage (ID-VD) characteristics of W/4H-SiC Schottky barrier diodes (SBDs) are investigated in the 303–448 K temperature range by means of a numerical simulation study. Results showed a good agreement with measurements for a bias current ranging from 100 nA up to 10 mA. The main device parameters, such as the barrier height and ideality factor are found strongly temperature-dependent. The observed behaviours are interpreted by using the thermionic emission (TE) theory with a single Gaussian distribution of the barrier height (BH). The corresponding Richardson constant is A* = 148.8 Acm−2K−2. This value is close to the theoretical one of 146 Acm−2K−2 for n-type 4H-SiC

    Effect of various electron and hole transport layers on the performance of CsPbI3-based perovskite solar cells: A numerical investigation in DFT, SCAPS-1D, and wxAMPS frameworks

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    CsPbI3 has recently received tremendous attention as a possible absorber of perovskite solar cells (PSCs). However, CsPbI3-based PSCs have yet to achieve the high performance of the hybrid PSCs. In this work, we performed a density functional theory (DFT) study using the Cambridge Serial Total Energy Package (CASTEP) code for the cubic CsPbI3 absorber to compare and evaluate its structural, electronic, and optical properties. The calculated electronic band gap (Eg) using the GGA-PBE approach of CASTEP was 1.483 eV for this CsPbI3 absorber. Moreover, the computed density of states (DOS) exhibited the dominant contribution from the Pb-5d orbital, and most charge also accumulated for the Pb atom as seen from the electronic charge density map. Fermi surface calculation showed multiband character, and optical properties were computed to investigate the optical response of CsPbI3. Furthermore, we used IGZO, SnO2, WS2, CeO2, PCBM, TiO2, ZnO, and C60 as the electron transport layers (ETLs), and Cu2O, CuSCN, CuSbS2, Spiro-MeOTAD, V2O5, CBTS, CFTS, P3HT, PEDOT: PSS, NiO, CuO, and CuI as the hole transport layers (HTLs) to identify the best HTL/CsPbI3/ETL combinations using the SCAPS-1D solar cell simulation software. Among 96 device structures, the best-optimized device structure, ITO/TiO2/CsPbI3/CBTS/Au was identified, which exhibited an efficiency of 17.9%. The effect of absorber and ETL thickness, series resistance, shunt resistance, and operating temperature was also evaluated for the six best devices along with their corresponding generation rate, recombination rate, capacitance-voltage, current density-voltage, and quantum efficiency characteristics. The obtained results from SCAPS-1D were also compared with wxAMPS simulation software.Comment: 34 pages, 12 figures, Supporting Information (3 figures

    An Investigation of Multidimensional Voice Program Parameters in Three Different Databases for Voice Pathology Detection and Classification

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    Background and Objective Automatic voice-pathology detection and classification systems may help clinicians to detect the existence of any voice pathologies and the type of pathology from which patients suffer in the early stages. The main aim of this paper is to investigate Multidimensional Voice Program (MDVP) parameters to automatically detect and classify the voice pathologies in multiple databases, and then to find out which parameters performed well in these two processes. Materials and Methods Samples of the sustained vowel /a/ of normal and pathological voices were extracted from three different databases, which have three voice pathologies in common. The selected databases in this study represent three distinct languages: (1) the Arabic voice pathology database; (2) the Massachusetts Eye and Ear Infirmary database (English database); and (3) the Saarbruecken Voice Database (German database). A computerized speech lab program was used to extract MDVP parameters as features, and an acoustical analysis was performed. The Fisher discrimination ratio was applied to rank the parameters. A t test was performed to highlight any significant differences in the means of the normal and pathological samples. Results The experimental results demonstrate a clear difference in the performance of the MDVP parameters using these databases. The highly ranked parameters also differed from one database to another. The best accuracies were obtained by using the three highest ranked MDVP parameters arranged according to the Fisher discrimination ratio: these accuracies were 99.68%, 88.21%, and 72.53% for the Saarbruecken Voice Database, the Massachusetts Eye and Ear Infirmary database, and the Arabic voice pathology database, respectively

    Pronostic visuel et évolution réfractive après chirurgie de la cataracte congénitale avec implantation primaire: Étude d’une série de 108 cas

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    La cataracte congénitale constitue la cause la plus fréquente de cécité évitable chez les enfants. Le but de cette étude est d'évaluer le pronosticréfractif et fonctionnel, des enfants opérés de cataracte congénitale avec implantation. Il s'agit d'une étude rétrospective de 108 enfants, dont 85cataractes bilatérales, 23 unilatérales opérés entre 2007 et 2011. La réfraction a été mesurée à 1 mois, 3 mois, 6 mois, 1 an, 2 ans, 3 ans et/ou 4 ans en post-opératoire. La meilleure acuité visuelle corrigée, ainsi que l'incidence des complications post-opératoires ont été analysé. L'âge moyen de la chirurgie était de 25 mois avec une durée moyenne de suivi de 3,17 ans. Les complications retrouvées étaient l'inflammation, la prolifération secondaire, et le glaucome. L'acuité visuelle (AV) moyenne corrigée finale était de 5,75/10e pour les formes bilatérales, et de  4,16/10e pour les unilatérales (p = 0,001). Les facteurs de mauvais pronostic retrouvés étaient l'âge tardif de la chirurgie, la densité de la cataracte et la survenue de complications (p = 0,001). L'incidence des complications post-opératoires était significativement plus élevé chez les enfants opérés à un jeune âge (p = 0,001). Les facteurs de mauvais pronostic visuel chez les enfants opérés pour cataracte congénitale avec implantation, sont représentés par le caractère unilatéral de la cataracte, l'âge tardif de la chirurgie, la densité de la cataracte et la survenue de complications post opératoires

    Analysis of a rapid increase of stratospheric ozone during late austral summer 2008 over Kerguelen (49.4° S, 70.3° E)

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    This paper reports on an increase of ozone event observed over Kerguelen (49.4° S, 70.3° E) in relationship with large-scale isentropic transport. This is evidenced by ground-based observations (co-localised radiosonde and SAOZ experiments) together with satellite global observations (Aura/MLS) assimilated into MOCAGE, a Méteo-France model. &lt;br&gt;&lt;br&gt; The study is based on the analyses of the first ozonesonde experiment never recorded at the Kerguelen site within the framework of a French campaign called ROCK that took place from April to August 2008. &lt;br&gt;&lt;br&gt; Comparisons and interpretations of the observed event are supported by co-localised SAOZ observations, by global mapping of tracers (O&lt;sub&gt;3&lt;/sub&gt;, N&lt;sub&gt;2&lt;/sub&gt;O and columns of O&lt;sub&gt;3&lt;/sub&gt;) from Aura/MLS and Aura/OMI experiments, and by model simulations of Ertel Potential Vorticity initialised by the ECMWF (European Centre for Medium-Range Weather Forecasts) data reanalyses. &lt;br&gt;&lt;br&gt; Satellite and ground-based observational data revealed a consistent increase of ozone in the local stratosphere by mid-April 2008. Additionally, Ozone (O&lt;sub&gt;3&lt;/sub&gt;) and nitrous oxide (N&lt;sub&gt;2&lt;/sub&gt;O) profiles obtained during January&amp;ndash;May 2008 using the Microwave Limb Sounder (MLS) aboard the Aura satellite are assimilated into MOCAGE (MOdèle de Chimie Atmosphérique à Grande Echelle), a global three-dimensional chemistry transport model of Météo-France. The assimilated total O&lt;sub&gt;3&lt;/sub&gt; values are consistent with SAOZ ground observations (within &amp;plusmn;5%), and isentropic distributions of O&lt;sub&gt;3&lt;/sub&gt; match well with maps of advected potential vorticity (APV) derived from the MIMOSA model, a high-resolution advection transport model, and from the ECMWF reanalysis. &lt;br&gt;&lt;br&gt; The event studied seems to be related to the isentropic transport of air masses that took place simultaneously in the lower- and middle-stratosphere, respectively from the polar region and from the tropics to the mid-latitudes. &lt;br&gt;&lt;br&gt; In fact, the ozone increase observed by mid April 2008 resulted simultaneously: (1) from an equator-ward departure of polar air masses characterised with a high-ozone layer in the lower stratosphere (near the 475 K isentropic level), and (2) from a reverse isentropic transport from the tropics to mid- and high-latitudes in the upper stratosphere (nearby the 700 K level). The increase of ozone observed over Kerguelen from the 16-April ozonesonde profile is thus attributed to a concomitant isentropic transport of ozone in two stratospheric layers: the tropical air moving southward and reaching over Kerguelen in the upper stratosphere, and the polar air passing over the same area but in the lower stratosphere

    A Review of Applications, Prospects, and Challenges of Proton-Conducting Zirconates in Electrochemical Hydrogen Devices

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    In the future, when fossil fuels are exhausted, alternative energy sources will be essential for everyday needs. Hydrogen-based energy can play a vital role in this aspect. This energy is green, clean, and renewable. Elec-trochemical hydrogen devices have been used extensively in nuclear power plants to manage hydrogen-based renewable fuel. Doped zirconate materials are commonly used as an electrolyte in these electrochemical devices. These materials have excellent physical stability and high proton transport numbers, which make them suitable for multiple applications. Doping enhances the physical and electronic properties of zirconate materials and makes them ideal for practical applications. This review highlights the applications of zirconate-based pro-ton-conducting materials in electrochemical cells, particularly in tritium monitors, tritium recovery, hydrogen sensors, and hydrogen pump systems. The central section of this review summarizes recent investigations and provides a comprehensive insight into the various doping schemes, experimental setup, instrumentation, op-timum operating conditions, morphology, composition, and performance of zirconate electrolyte materials. In addition, different challenges that are hindering zirconate materials from achieving their full potential in elec-trochemical hydrogen devices are discussed. Finally, this paper lays out a few pathways for aspirants who wish to undertake research in this field.Comment: 31 pages, 13 figure
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