Search results for: cubic normal distribution
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7838

Search results for: cubic normal distribution

4628 Spray-Dried, Biodegradable, Drug-Loaded Microspheres for Use in the Treatment of Lung Diseases

Authors: Mazen AlGharsan

Abstract:

Objective: The Carbopol Microsphere of Linezolid, a drug used to treat lung disease (pulmonary disease), was prepared using Buchi B-90 nano spray-drier. Methods: Production yield, drug content, external morphology, particle size, and in vitro release pattern were performed. Results: The work was 79.35%, and the drug content was 66.84%. The surface of the particles was shriveled in shape, with particle size distribution with a mean diameter of 9.6 µm; the drug was released in a biphasic manner with an initial release of 25.2 ± 5.7% at 60 minutes. It later prolonged the release by 95.5 ± 2.5% up to 12 hours. Differential scanning calorimetry (DSC) revealed no change in the melting point of the formulation. Fourier-transform infrared (FT-IR) studies showed no polymer-drug interaction in the prepared nanoparticles.

Keywords: nanotechnology, drug delivery, Linezolid, lung disease

Procedia PDF Downloads 13
4627 Human Health Risks Assessment of Particulate Air Pollution in Romania

Authors: Katalin Bodor, Zsolt Bodor, Robert Szep

Abstract:

The particulate matter (PM) smaller than 2.5 μm are less studied due to the limited availability of PM₂.₅, and less information is available on the health effects attributable to PM₁₀ in Central-Eastern Europe. The objective of the current study was to assess the human health risk and characterize the spatial and temporal variation of PM₂.₅ and PM₁₀ in eight Romanian regions between the 2009-2018 and. The PM concentrations showed high variability over time and spatial distribution. The highest concentration was detected in the Bucharest region in the winter period, and the lowest was detected in West. The relative risk caused by the PM₁₀ for all-cause mortality varied between 1.017 (B) and 1.025 (W), with an average 1.020. The results demonstrate a positive relative risk of cardiopulmonary and lung cancer disease due to exposure to PM₂.₅ on the national average 1.26 ( ± 0.023) and 1.42 ( ± 0.037), respectively.

Keywords: PM₂.₅, PM₁₀, relative risk, health effect

Procedia PDF Downloads 161
4626 The Effects of Normal Aging on Reasoning Ability: A Dual-Process Approach

Authors: Jamie A. Prowse Turner, Jamie I. D. Campbell, Valerie A. Thompson

Abstract:

The objective of the current research was to use a dual-process theory framework to explain these age-related differences in reasoning. Seventy-two older (M = 80.0 years) and 72 younger (M = 24.6 years) adults were given a variety of reasoning tests (i.e., a syllogistic task, base rate task, the Cognitive Reflection Test, and a perspective manipulation), as well as independent tests of capacity (working memory, processing speed, and inhibition), thinking styles, and metacognitive ability, to account for these age-related differences. It was revealed that age-related differences were limited to problems that required Type 2 processing and were related to differences in cognitive capacity, individual difference factors, and strategy choice. Furthermore, older adults’ performance can be improved by reasoning from another’s’ perspective and cannot, at this time, be explained by metacognitive differences between young and older adults. All of these findings fit well within a dual-process theory of reasoning, which provides an integrative framework accounting for previous findings and the findings presented in the current manuscript.

Keywords: aging, dual-process theory, performance, reasoning ability

Procedia PDF Downloads 191
4625 Towards Accurate Velocity Profile Models in Turbulent Open-Channel Flows: Improved Eddy Viscosity Formulation

Authors: W. Meron Mebrahtu, R. Absi

Abstract:

Velocity distribution in turbulent open-channel flows is organized in a complex manner. This is due to the large spatial and temporal variability of fluid motion resulting from the free-surface turbulent flow condition. This phenomenon is complicated further due to the complex geometry of channels and the presence of solids transported. Thus, several efforts were made to understand the phenomenon and obtain accurate mathematical models that are suitable for engineering applications. However, predictions are inaccurate because oversimplified assumptions are involved in modeling this complex phenomenon. Therefore, the aim of this work is to study velocity distribution profiles and obtain simple, more accurate, and predictive mathematical models. Particular focus will be made on the acceptable simplification of the general transport equations and an accurate representation of eddy viscosity. Wide rectangular open-channel seems suitable to begin the study; other assumptions are smooth-wall, and sediment-free flow under steady and uniform flow conditions. These assumptions will allow examining the effect of the bottom wall and the free surface only, which is a necessary step before dealing with more complex flow scenarios. For this flow condition, two ordinary differential equations are obtained for velocity profiles; from the Reynolds-averaged Navier-Stokes (RANS) equation and equilibrium consideration between turbulent kinetic energy (TKE) production and dissipation. Then different analytic models for eddy viscosity, TKE, and mixing length were assessed. Computation results for velocity profiles were compared to experimental data for different flow conditions and the well-known linear, log, and log-wake laws. Results show that the model based on the RANS equation provides more accurate velocity profiles. In the viscous sublayer and buffer layer, the method based on Prandtl’s eddy viscosity model and Van Driest mixing length give a more precise result. For the log layer and outer region, a mixing length equation derived from Von Karman’s similarity hypothesis provides the best agreement with measured data except near the free surface where an additional correction based on a damping function for eddy viscosity is used. This method allows more accurate velocity profiles with the same value of the damping coefficient that is valid under different flow conditions. This work continues with investigating narrow channels, complex geometries, and the effect of solids transported in sewers.

Keywords: accuracy, eddy viscosity, sewers, velocity profile

Procedia PDF Downloads 112
4624 Early Recognition and Grading of Cataract Using a Combined Log Gabor/Discrete Wavelet Transform with ANN and SVM

Authors: Hadeer R. M. Tawfik, Rania A. K. Birry, Amani A. Saad

Abstract:

Eyes are considered to be the most sensitive and important organ for human being. Thus, any eye disorder will affect the patient in all aspects of life. Cataract is one of those eye disorders that lead to blindness if not treated correctly and quickly. This paper demonstrates a model for automatic detection, classification, and grading of cataracts based on image processing techniques and artificial intelligence. The proposed system is developed to ease the cataract diagnosis process for both ophthalmologists and patients. The wavelet transform combined with 2D Log Gabor Wavelet transform was used as feature extraction techniques for a dataset of 120 eye images followed by a classification process that classified the image set into three classes; normal, early, and advanced stage. A comparison between the two used classifiers, the support vector machine SVM and the artificial neural network ANN were done for the same dataset of 120 eye images. It was concluded that SVM gave better results than ANN. SVM success rate result was 96.8% accuracy where ANN success rate result was 92.3% accuracy.

Keywords: cataract, classification, detection, feature extraction, grading, log-gabor, neural networks, support vector machines, wavelet

Procedia PDF Downloads 332
4623 Histomorphological Comparisons of Liver of Broiler Chickens and Wild Boar in Algeria

Authors: Khenenou Tarek

Abstract:

Aim: The objective of present study was to compare the normal macro and microscopic appearance of the liver in two very different species, one is an omnivorous mammal; the wild boar and the other belongs to the family of poultry; broiler chicken from the region of Bouhmama (Khenchela). Materials and methods: Eight broilers (58 days of age) and eight wild boars were included in the experiment to obtain information about the morpho-histological appearances of liver in two species. Results: There is a big difference in the liver appearance between the two species, in the wild boar it is of firm consistency with a tiger aspect and divided into four lobes, whereas in the broiler, the liver is brown and sometimes pale during the first 10-14 days, so it was divided into two lobes. Concerning the liver parenchyma, we used the Russian LOMBO MBS-10 stereo microscope, our results showed that the liver parenchyma was well developed in wild boar than in broiler chickens whereas, in broiler chickens; an excessive development of the sinus; the latter were less developed in the wild boar. Conclusion: The macroscopic observation showed a marked difference in liver between the two species. The microscopic examination of liver showed that the parenchyma is less pronounced in broilers whereas the sinuses were highly developed in the wild boar.

Keywords: broiler chicken, liver, macro and microscopic appearances, wild boar, Algeria

Procedia PDF Downloads 21
4622 Structural, Magnetic, Dielectric, and Electrical Properties of ZnFe2O4 Nanoparticles

Authors: Raghvendra Singh Yadav, Ivo Kuřitka, Jarmila Vilcakova, Pavel Urbanek, Michal Machovsky, Milan Masař, Martin Holek

Abstract:

ZnFe2O4 spinel ferrite nanoparticles were synthesized by sol-gel auto-combustion method. The synthesized spinel ferrite nanoparticles were annealed at different higher temperature to achieve different size nanoparticles. The as synthesized and annealed samples were characterized by powder X-ray Diffraction Spectroscopy, Raman Spectroscopy, Fourier Transform Infrared Spectroscopy, UV-Vis absorption Spectroscopy and Scanning Electron Microscopy. The magnetic properties were studied by vibrating sample magnetometer. The variation in magnetic parameters was noticed with variation in grain size. The dielectric constant and dielectric loss with variation of frequency shows normal behaviour of spinel ferrite. The variation in conductivity with variation in grain size is noticed. Modulus and Impedance Spectroscopy shows the role of grain and grain boundary on the electrical resistance and capacitance of different grain sized spinel ferrite nanoparticles. Acknowledgment: This work was supported by the Ministry of Education, Youth and Sports of the Czech Republic – Program NPU I (LO1504).

Keywords: spinel ferrite, nanoparticles, magnetic properties, dielectric properties

Procedia PDF Downloads 428
4621 Oblique Wing: Future Generation Transonic Aircraft

Authors: Mushfiqul Alam, Kashyapa Narenathreyas

Abstract:

The demand for efficient transonic transport has been growing every day and may turn out to be the most pressed innovation in coming years. Oblique wing configuration was proposed as an alternative to conventional wing configuration for supersonic and transonic passenger aircraft due to its aerodynamic advantages. This paper re-demonstrates the aerodynamic advantages of oblique wing configuration using open source CFD code. The aerodynamic data were generated using Panel Method. Results show that Oblique Wing concept with elliptical wing planform offers a significant reduction in drag at transonic and supersonic speeds and approximately twice the lift distribution compared to conventional operating aircrafts. The paper also presents a preliminary conceptual aircraft sizing which can be used for further experimental analysis.

Keywords: aerodynamics, asymmetric sweep, oblique wing, swing wing

Procedia PDF Downloads 555
4620 Enhancement of Hardness Related Properties of Grey Cast Iron Powder Reinforced AA7075 Metal Matrix Composites Through T6 and T8 Heat Treatments

Authors: S. S. Sharma, P. R. Prabhu, K. Jagannath, Achutha Kini U., Gowri Shankar M. C.

Abstract:

In present global scenario, aluminum alloys are coining the attention of many innovators as competing structural materials for automotive and space applications. Comparing to other challenging alloys, especially, 7xxx series aluminum alloys have been studied seriously because of their benefits such as moderate strength; better deforming characteristics, excellent chemical decay resistance, and affordable cost. 7075 Al-alloys have been used in the transportation industry for the fabrication of several types of automobile parts, such as wheel covers, panels and structures. It is expected that substitution of such aluminum alloys for steels will result in great improvements in energy economy, durability and recyclability. However, it is necessary to improve the strength and the formability levels at low temperatures in aluminium alloys for still better applications. Aluminum–Zinc–Magnesium with or without other wetting agent denoted as 7XXX series alloys are medium strength heat treatable alloys. Cu, Mn and Si are the other solute elements which contribute for the improvement in mechanical properties achievable by selecting and tailoring the suitable heat treatment process. On subjecting to suitable treatments like age hardening or cold deformation assisted heat treatments, known as low temperature thermomechanical treatments (LTMT) the challenging properties might be incorporated. T6 is the age hardening or precipitation hardening process with artificial aging cycle whereas T8 comprises of LTMT treatment aged artificially with X% cold deformation. When the cold deformation is provided after solution treatment, there is increase in hardness related properties such as wear resistance, yield and ultimate strength, toughness with the expense of ductility. During precipitation hardening both hardness and strength of the samples are increasing. Decreasing peak hardness value with increasing aging temperature is the well-known behavior of age hardenable alloys. The peak hardness value is further increasing when room temperature deformation is positively supported with age hardening known as thermomechanical treatment. Considering these aspects, it is intended to perform heat treatment and evaluate hardness, tensile strength, wear resistance and distribution pattern of reinforcement in the matrix. 2 to 2.5 and 3 to 3.5 times increase in hardness is reported in age hardening and LTMT treatments respectively as compared to as-cast composite. There was better distribution of reinforcements in the matrix, nearly two fold increase in strength levels and upto 5 times increase in wear resistance are also observed in the present study.

Keywords: reinforcement, precipitation, thermomechanical, dislocation, strain hardening

Procedia PDF Downloads 311
4619 Friction Calculation and Simulation of Column Electric Power Steering System

Authors: Seyed Hamid Mirmohammad Sadeghi, Raffaella Sesana, Daniela Maffiodo

Abstract:

This study presents a procedure for friction calculation of column electric power steering (C-EPS) system which affects handling and comfort in driving. The friction losses estimation is obtained from experimental tests and mathematical calculation. Parts in C-EPS mainly involved in friction losses are bearings and worm gear. In the theoretical approach, the gear geometry and Hertz law were employed to measure the normal load and the sliding velocity and contact areas from the worm gears driving conditions. The viscous friction generated in the worm gear was obtained with a theoretical approach and the result was applied to model the friction in the steering system. Finally, by viscous friction coefficient and Coulomb friction coefficient, values of friction in worm gear were calculated. According to the Bearing Company and the characteristics of each bearing, the friction torques due to load and due to speed were calculated. A MATLAB Simulink model for calculating the friction in bearings and worm gear in C-EPS were done and the total friction value was estimated.

Keywords: friction, worm gear, column electric power steering system, simulink, bearing, EPS

Procedia PDF Downloads 358
4618 Experimental Investigation with Different Inclination Angles on Copper Oscillating Heat Pipes Performance Using Fe2O3 / Kerosene under Magnetic Field

Authors: H. R. Goshayeshi, M. Mansori, M. Ahmady, M. Zhaloyi

Abstract:

This paper presents the result of an experimental investigation regarding the use of Fe2O3 nanoparticles added to Kerosene as a working fluid, under magnetic field for Copper Oscillating Heat pipe with inclination angle of 0°(horizontal), 15°, 30°, 45°, 60°, 75°, and 90° (vertical). The following were examined; measure the temperature distribution and heat transfer rate on Oscillating Heat Pipe (OHP), with magnetic field under different angles. Results showed that the addition of Fe2O3 nanoparticles under magnetic field improved thermal performance of OHP especially in 75°.

Keywords: copper oscillating heat pipe, Fe2O3, magnetic field, inclination angles

Procedia PDF Downloads 365
4617 Study of Ion Density Distribution and Sheath Thickness in Warm Electronegative Plasma

Authors: Rajat Dhawan, Hitendra K. Malik

Abstract:

Electronegative plasmas comprising electrons, positive ions, and negative ions are advantageous for their expanding applications in industries. In plasma cleaning, plasma etching, and plasma deposition process, electronegative plasmas are preferred because of relatively less potential developed on the surface of the material under investigation. Also, the presence of negative ions avoid the irregularity in etching shapes and also enhance the material working during the fabrication process. The interaction of metallic conducting surface with plasma becomes mandatory to understand these applications. A metallic conducting probe immersed in a plasma results in the formation of a thin layer of charged species around the probe called as a sheath. The density of the ions embedded on the surface of the material and the sheath thickness are the important parameters for the surface-plasma interaction. Sheath thickness will give rise to the information of affected plasma region due to conducting surface/probe. The knowledge of the density of ions in the sheath region is advantageous in plasma nitriding, and their temperature is equally important as it strongly influences the thickness of the modified layer during surface plasma interaction. In the present work, we considered a negatively biased metallic probe immersed in a warm electronegative plasma. For this system, we adopted the continuity equation and momentum transfer equation for both the positive and negative ions, whereas electrons are described by Boltzmann distribution. Finally, we use the Poisson’s equation. Here, we assumed the spherical geometry for small probe radius. Poisson’s equation reveals the behaviour of potential surrounding a conducting metallic probe along with the use of the continuity and momentum transfer equations, with the help of proper boundary conditions. In turn, it gives rise to the information about the density profile of charged species and most importantly the thickness of the sheath. By keeping in mind, the well-known Bohm-Sheath criterion, all calculations are done. We found that positive ion density decreases with an increase in positive ion temperature, whereas it increases with the higher temperature of the negative ions. Positive ion density decreases as we move away from the center of the probe and is found to show a discontinuity at a particular distance from the center of the probe. The distance where discontinuity occurs is designated as sheath edge, i.e., the point where sheath ends. These results are beneficial for industrial applications, as the density of ions embedded on material surface is strongly affected by the temperature of plasma species. It has a drastic influence on the surface properties, i.e., the hardness, corrosion resistance, etc. of the materials.

Keywords: electronegative plasmas, plasma surface interaction positive ion density, sheath thickness

Procedia PDF Downloads 132
4616 Study of Transport in Electronic Devices with Stochastic Monte Carlo Method: Modeling and Simulation along with Submicron Gate (Lg=0.5um)

Authors: N. Massoum, B. Bouazza

Abstract:

In this paper, we have developed a numerical simulation model to describe the electrical properties of GaInP MESFET with submicron gate (Lg = 0.5 µm). This model takes into account the three-dimensional (3D) distribution of the load in the short channel and the law effect of mobility as a function of electric field. Simulation software based on a stochastic method such as Monte Carlo has been established. The results are discussed and compared with those of the experiment. The result suggests experimentally that, in a very small gate length in our devices (smaller than 40 nm), short-channel tunneling explains the degradation of transistor performance, which was previously enhanced by velocity overshoot.

Keywords: Monte Carlo simulation, transient electron transport, MESFET device, simulation software

Procedia PDF Downloads 513
4615 A Blind Three-Dimensional Meshes Watermarking Using the Interquartile Range

Authors: Emad E. Abdallah, Alaa E. Abdallah, Bajes Y. Alskarnah

Abstract:

We introduce a robust three-dimensional watermarking algorithm for copyright protection and indexing. The basic idea behind our technique is to measure the interquartile range or the spread of the 3D model vertices. The algorithm starts by converting all the vertices to spherical coordinate followed by partitioning them into small groups. The proposed algorithm is slightly altering the interquartile range distribution of the small groups based on predefined watermark. The experimental results on several 3D meshes prove perceptual invisibility and the robustness of the proposed technique against the most common attacks including compression, noise, smoothing, scaling, rotation as well as combinations of these attacks.

Keywords: watermarking, three-dimensional models, perceptual invisibility, interquartile range, 3D attacks

Procedia PDF Downloads 474
4614 Geostatistical Analysis of Contamination of Soils in an Urban Area in Ghana

Authors: S. K. Appiah, E. N. Aidoo, D. Asamoah Owusu, M. W. Nuonabuor

Abstract:

Urbanization remains one of the unique predominant factors which is linked to the destruction of urban environment and its associated cases of soil contamination by heavy metals through the natural and anthropogenic activities. These activities are important sources of toxic heavy metals such as arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), and lead (Pb), nickel (Ni) and zinc (Zn). Often, these heavy metals lead to increased levels in some areas due to the impact of atmospheric deposition caused by their proximity to industrial plants or the indiscriminately burning of substances. Information gathered on potentially hazardous levels of these heavy metals in soils leads to establish serious health and urban agriculture implications. However, characterization of spatial variations of soil contamination by heavy metals in Ghana is limited. Kumasi is a Metropolitan city in Ghana, West Africa and is challenged with the recent spate of deteriorating soil quality due to rapid economic development and other human activities such as “Galamsey”, illegal mining operations within the metropolis. The paper seeks to use both univariate and multivariate geostatistical techniques to assess the spatial distribution of heavy metals in soils and the potential risk associated with ingestion of sources of soil contamination in the Metropolis. Geostatistical tools have the ability to detect changes in correlation structure and how a good knowledge of the study area can help to explain the different scales of variation detected. To achieve this task, point referenced data on heavy metals measured from topsoil samples in a previous study, were collected at various locations. Linear models of regionalisation and coregionalisation were fitted to all experimental semivariograms to describe the spatial dependence between the topsoil heavy metals at different spatial scales, which led to ordinary kriging and cokriging at unsampled locations and production of risk maps of soil contamination by these heavy metals. Results obtained from both the univariate and multivariate semivariogram models showed strong spatial dependence with range of autocorrelations ranging from 100 to 300 meters. The risk maps produced show strong spatial heterogeneity for almost all the soil heavy metals with extremely risk of contamination found close to areas with commercial and industrial activities. Hence, ongoing pollution interventions should be geared towards these highly risk areas for efficient management of soil contamination to avert further pollution in the metropolis.

Keywords: coregionalization, heavy metals, multivariate geostatistical analysis, soil contamination, spatial distribution

Procedia PDF Downloads 300
4613 Challenging Clinical Scenario of Blood Stream Candida Infections – An Indian Experience

Authors: P. Uma Devi, S. Sujith, K. Rahul, T. S. Dipu, V. Anil Kumar , Vidya Menon

Abstract:

Introduction: Candida is an important cause of bloodstream infections (BSIs), causing significant mortality and morbidity. The epidemiology of Candida infection is also changing, mainly in relation to the number of episodes caused by species Candida non-albicans. However, in India, the true burden of candidemia is not clear. Thus, this study was conducted to evaluate the clinical characteristics, species distribution, antifungal susceptibility and outcome of candidemia at our hospital. Methodology: Between January 2012 and April 2014, adult patients with at least one positive blood culture for Candida species were identified through the microbiology laboratory database (for each patient only the first episode of candidemia was recorded). Patient data was collected by retrospective chart review of clinical characteristics including demographic data, risk factors; species distribution, resistance to antifungals and survival. Results: A total of 165 episodes of Candida BSI were identified, with 115 episodes occurring in adult patients. Most of the episodes occurred in males (69.6%). Nearly 82.6% patients were between 41 to 80 years and majority of the patients were in the intensive care unit (65.2%) at the time of diagnosis. On admission, 26.1% and 18.3% patients had pneumonia and urinary tract infection, respectively. Majority of the candidemia episodes were found in the general medicine department (23.5%) followed by gastrointestinal surgery (13.9%) and medical oncology & haematology (13%). Risk factors identified were prior hospitalization within one year (83.5%), antibiotic therapy within the last one month (64.3%), indwelling urinary catheter (63.5%), central venous catheter use (59.1%), diabetes mellitus (53%), severe sepsis (45.2%), mechanical ventilation (43.5%) and surgery (36.5%). C. tropicalis (30.4%) was the leading cause of infection followed by C. parapsilosis (28.7%) and C. albicans (13%). Other non-albicans species isolated included C. haemulonii (7.8%), C. glabrata (7%), C. famata (4.3%) and C. krusei (1.7%). Antifungal susceptibility to fluconazole was 87.9% (C. parapsilosis), 100% (C. tropicalis) and 93.3% (C. albicans). Mortality was noted in 51 patients (44.3%). Early mortality (within 7 days) was noted in 32 patients while late mortality (between 7 and 30 days) was noted in 19 patients. Conclusion: In recent years, candidemia has been flourishing in critically ill patients. Comparison of data from our own hospital from 2005 shows a doubling of the incidence. Rapid changes in the rate of infection, potential risk factors, and emergence of non-albicans Candida demand continued surveillance of this serious BSI. High index of suspicion and sensitive diagnostics are essential to improve outcomes in resource limited settings with emergence of non-albicans Candida.

Keywords: antifungal susceptibility, candida albicans, candidemia, non-albicans candida

Procedia PDF Downloads 455
4612 Measuring the Visibility of the European Open Access Journals with Bibliometric Indicators

Authors: Maja Jokić, Andrea Mervar, Stjepan Mateljan

Abstract:

Peer review journals, as the main communication channel among researchers, fully achieve their objective if they are available to the global research community, which is accomplished through open access. In the EU countries, the idea of open access has spread over the years through various projects, initiatives, and strategic documents. Consequently, in this paper we want to analyze, using various bibliometric indicators, visibility, and significance of open access peer review journals compared to the conventional (non-open access) ones. We examine the sample of open access (OA) journals in 28 EU countries in addition to open access journals in three EU candidate countries (Bosnia and Herzegovina, FYR Macedonia and Serbia), all indexed by Scopus (N=1,522). These journals comprise 42% of the total number of OA journals indexed by Scopus. The distribution of OA journals in our sample according to the subject fields indicates that the largest share has OA journals in Health Sciences, 29% followed by Social Sciences and Physical Sciences with 25%, and 21% in Life Sciences. At the same time, the distribution according to countries (N=31) shows the dominance of EU15 countries with the share of 68.3% (N=1041) while post-socialist European countries (EU11 plus three candidate EU countries) have the share of 31.6% (N=481). Bibliometric indicators are derived from the SCImago Journal Ranking database. The analysis of OA journals according to their quartile scores (that reflect the relation between number of articles and their citations) shows that the largest number of OA journals from our sample was in the third quartile in 2015. For comparison, the majority of all academic journals indexed in Scopus from the countries in our sample were in the same year in the first quartile. The median of SJR indicator (SCImago Journal Rankings) for 2015 that measures the journal's prestige, amounted 0.297 for OA journals from the sample, while it was modestly lower for all OA journals, 0.284. The value of the same indicator for all journals indexed by Scopus (N=11,086) from our group of countries was 0.358, which is significantly different from the one for OA journals. Apart from the number of OA journals we also confirm significant differences between EU15 and post-socialist countries in bibliometric status of OA journals. The median SJR indicator for 2015 for EU15 countries was 0.394, while for post-socialist countries it amounted to 0.226. The changes in bibliometric indicators: quartile score, SJR (SCImago Journal Rankings), SNIP (Sources Normalised Impact by Paper) and IPP (Impact per Publication) of OA journals during 2012-2015 period, as well as H-index for the main four subject fields (Life Sciences, Physical Sciences, Social Sciences and Health Sciences) in the whole sample as well as in two main groups of European countries, show increasing trend of acceptance and visibility of OA journals within the academic community. More comprehensive insights into the visibility of OA journals could be reached by using additional qualitative research methods such as for example, interviews with researchers.

Keywords: bibliometric analysis, European countries, journal evaluation, open access journals

Procedia PDF Downloads 222
4611 Component Comparison of Polyaluminum Chloride Produced from Various Methods

Authors: Wen Po Cheng, Chia Yun Chung, Ruey Fang Yu, Chao Feng Chen

Abstract:

The main objective of this research was to study the differences of aluminum hydrolytic products between two PACl preparation methods. These two methods were the acidification process of freshly formed amorphous Al(OH)3 and the conventional alkalization process of aluminum chloride solution. According to Ferron test and 27Al NMR analysis of those two PACl preparation procedures, the reaction rate constant (k) values and Al13 percentage of acid addition process at high basicity value were both lower than those values of the alkaline addition process. The results showed that the molecular structure and size distribution of the aluminum species in both preparing methods were suspected to be significantly different at high basicity value.

Keywords: polyaluminum chloride, Al13, amorphous aluminum hydroxide, Ferron test

Procedia PDF Downloads 376
4610 A Guide to User-Friendly Bash Prompt: Adding Natural Language Processing Plus Bash Explanation to the Command Interface

Authors: Teh Kean Kheng, Low Soon Yee, Burra Venkata Durga Kumar

Abstract:

In 2022, as the future world becomes increasingly computer-related, more individuals are attempting to study coding for themselves or in school. This is because they have discovered the value of learning code and the benefits it will provide them. But learning coding is difficult for most people. Even senior programmers that have experience for a decade year still need help from the online source while coding. The reason causing this is that coding is not like talking to other people; it has the specific syntax to make the computer understand what we want it to do, so coding will be hard for normal people if they don’t have contact in this field before. Coding is hard. If a user wants to learn bash code with bash prompt, it will be harder because if we look at the bash prompt, we will find that it is just an empty box and waiting for a user to tell the computer what we want to do, if we don’t refer to the internet, we will not know what we can do with the prompt. From here, we can conclude that the bash prompt is not user-friendly for new users who are learning bash code. Our goal in writing this paper is to give an idea to implement a user-friendly Bash prompt in Ubuntu OS using Artificial Intelligent (AI) to lower the threshold of learning in Bash code, to make the user use their own words and concept to write and learn Bash code.

Keywords: user-friendly, bash code, artificial intelligence, threshold, semantic similarity, lexical similarity

Procedia PDF Downloads 142
4609 The Effect of the Weld Current Types on Microstructure and Hardness in Tungsten Inert Gas Welding of the AZ31 Magnesium Alloy Sheet

Authors: Bilge Demir, Ahmet Durgutlu, Mustafa Acarer

Abstract:

In this study, the butt welding of the commercial AZ31 magnesium alloy sheets have been carried out by using Tungsten Inert Gas (TIG) welding process with alternative and pulsed current. Welded samples were examined with regards to hardness and microstructure. Despite some recent developments in welding of magnesium alloys, they have some problems such as porosity, hot cracking, oxide formation and so on. Samples of the welded parts have undergone metallographic and mechanical examination. Porosities and homogeneous micron grain oxides were rarely observed. Orientations of the weld microstructure in terms of heat transfer also were rarely observed and equiaxed grain morphology was dominant grain structure as in the base metal. As results, fusion zone and few locations of the HAZ of the welded samples have shown twin’s grains. Hot cracking was not observed for any samples. Weld bead geometry of the welded samples were evaluated as normal according to welding parameters. In the results, conditions of alternative and pulsed current and the samples were compared to each other with regards to microstructure and hardness.

Keywords: AZ31 magnesium alloy, microstructures, micro hardness TIG welding

Procedia PDF Downloads 390
4608 Diversity and Distribution of Benthic Invertebrates in the West Port, Malaysia

Authors: Seyedeh Belin Tavakoly Sany, Rosli Hashim, Majid Rezayi, Aishah Salleh, Omid Safari

Abstract:

The purpose of this paper is to describe the main characteristics of macroinvertebrate species in response to environmental forcing factors. Overall, 23 species of Mollusca, 4 species of Arthropods, 3 species of Echinodermata and 3 species of Annelida were identified at the 9 sampling stations during four sampling periods. Individual species of Mollusca constituted 36.4% of the total abundance, followed by Arthropods (27.01%), Annelida (34.3%) and Echinodermata (2.4%). The results of Kruskal-Wallis test indicated that a significant difference (p <0.05) in the abundance, richness and diversity of the macro-benthic community in different stations. The correlation analysis revealed that anthropogenic pollution and natural variability caused by these variations in spatial scales.

Keywords: benthic invertebrates, diversity, abundance, West Port

Procedia PDF Downloads 441
4607 Measurements of Radial Velocity in Fixed Fluidized Bed for Fischer-Tropsch Synthesis Using LDV

Authors: Xiaolai Zhang, Haitao Zhang, Qiwen Sun, Weixin Qian, Weiyong Ying

Abstract:

High temperature Fischer-Tropsch synthesis process use fixed fluidized bed as a reactor. In order to understand the flow behavior in the fluidized bed better, the research of how the radial velocity affect the entire flow field is necessary. Laser Doppler Velocimetry (LDV) was used to study the radial velocity distribution along the diameter direction of the cross-section of the particle in a fixed fluidized bed. The velocity in the cross-section is fluctuating within a small range. The direction of the speed is a random phenomenon. In addition to r/R is 1, the axial velocity are more than 6 times of the radial velocity, the radial velocity has little impact on the axial velocity in a fixed fluidized bed.

Keywords: Fischer-Tropsch synthesis, Fixed fluidized bed, LDV, Velocity

Procedia PDF Downloads 404
4606 Wear Behavior of Grey Cast Iron Coated with Al2O3-13TiO2 and Ni20Cr Using Detonation Spray Process

Authors: Harjot Singh Gill, Neelkanth Grover, Jwala Parshad Singla

Abstract:

The main aim of this research work is to present the effect of coating on two different grades of grey cast iron using detonation spray method. Ni20Cr and Al2O3-13TiO2 powders were sprayed using detonation gun onto GI250 and GIHC substrates and the results as well as coating surface morphology of the coating is studied by XRD and SEM/EDAX analysis. The wear resistance of Ni20Cr and Al2O3-13TiO2 has been investigated on pin-on-disc tribometer using ASTM G99 standards. Cumulative wear rate and coefficient of friction (µ) were calculated under three normal load of 30N, 40N, 50N at constant sliding velocity of 1m/s. Worn out surfaces were analyzed by SEM/EDAX. The results show significant resistance to wear with Al2O3-13TiO2 coating as compared to Ni20Cr and bare substrates. SEM/EDAX analysis and cumulative wear loss bar charts clearly explain the wear behavior of coated as well as bare sample of GI250 and GIHC.

Keywords: detonation spray, grey cast iron, wear rate, coefficient of friction

Procedia PDF Downloads 367
4605 Torrefaction of Biomass Pellets: Modeling of the Process in a Fixed Bed Reactor

Authors: Ekaterina Artiukhina, Panagiotis Grammelis

Abstract:

Torrefaction of biomass pellets is considered as a useful pretreatment technology in order to convert them into a high quality solid biofuel that is more suitable for pyrolysis, gasification, combustion and co-firing applications. In the course of torrefaction the temperature varies across the pellet, and therefore chemical reactions proceed unevenly within the pellet. However, the uniformity of the thermal distribution along the pellet is generally assumed. The torrefaction process of a single cylindrical pellet is modeled here, accounting for heat transfer coupled with chemical kinetics. The drying sub-model was also introduced. The non-stationary process of wood pellet decomposition is described by the system of non-linear partial differential equations over the temperature and mass. The model captures well the main features of the experimental data.

Keywords: torrefaction, biomass pellets, model, heat, mass transfer

Procedia PDF Downloads 480
4604 Haematological and Internal Organs Characteristics of Rabbit Bucks Feed Boiled Pigeon Pea (Cajanus Cajan) Seed Meal

Authors: N. S. Okoro

Abstract:

An experiment was conducted to determine the growth performance, blood parameters and reproductive characteristics of 8-week old male weaner rabbits fed 2% boiled pigeon pea seed meal. The study lasted for 16 weeks. Results showed that hematological parameters of the two groups of rabbit bucks were not significantly affected (p > 0.05) by the treatment, meaning that the PPSM was adequate for maintaining the blood parameters at the normal levels. The 20% boiled PPSM significantly affected (P < 0.05) serum Alanine Aminotransferase (ALT) (67.72±2.5 I.U/I) more than the ALT (57.50±2.02 I.U/I) of the control, which is an indication of liver problem. The globulin level (3.00 ± 0.23g/dl) of the 20% boiled PPSM group was significantly higher than that of the control (2.60±0.06 g/dl), indicating that the test diet did not alter protein metabolism in the rabbits. Boiled pigeon pea seed meal supported organ weight and testicular development in rabbit bucks, suggesting that boiling reduced the level of the anti-nutritional factors in pigeon pea seed meal. Thus, 20% boiled pigeon pea can be included in diets of rabbits without adverse effect on blood parameters and internal organs characteristics.

Keywords: hematology, internal organs, Pigeon pea, rabbits, serum biochemistry

Procedia PDF Downloads 395
4603 Incidence and Prevalence of Dry Eye Syndrome in Different Occupational Sector of Society

Authors: Vergeena Varghese, G. Gajalakshmi, Jayarajini Vasanth

Abstract:

The present study deals with the indication of prevalence of dry eye and evaluates environmental risk factors attributed to dry eye in different occupational sectors. 240 subjects above 20 years and below 45 years of age were screened for dry eye. Mcmonnies dry eye questionnaire based history and Schirmer’s test were used to diagnose dry eye. For Schirmer’s test Whatman strip and paracaine drop used as an anesthetic. Subject’s demographics include age, sex, smoking, alcoholism, occupation history and working environment. Out of a total of 240 subjects, 52 subjects were positive for dry eye syndrome (21.7%). The highest prevalence of dry eye syndrome in software sector was 14subjects (26.9%) out of a total of 40 subjects. In the construction sector, the prevalence of dry eye syndrome had 12 subjects (23.1%) out of 40 subjects and 9 subjects (17.3%) out of 40 subjects in agriculture sector. 7 subjects (13.5%) who had dry eye out of 40 subjects in the transport sector and in industrial 6 subjects (11.5%). In a normal sector, this was taken as control group had dry eye in 4 subjects (7.7%) out of 40 subjects. We also found the prevalence of dry eye in OS was higher than OD. Dry eye is a most common ocular condition. The highest prevalence of dry eye syndrome in software sector was 14 members than other sector. There was a significant correlation between environmental and occupational factors to cause dry eye. Excessive exposure to sunlight, wind, high temperature, and air pollution, electromagnetic radiation are the factors affect the tear film and ocular surface causing the dry eye syndrome.

Keywords: DES – dry eye syndrome, Mcmonnies dry eye questionnaire, schirmer’s test, whatman vstrip

Procedia PDF Downloads 468
4602 Antiprotozoal Activity of Peganum harmala against Babesiosis in Cattle

Authors: Muhammad Mustafa Jafar, Syed Ashar Mahfooz, Muhammad Ejaz Saleem, Muhammad Asif Raza, Asghar Abbas, Rao Zahid Abbas, Muhammad Kasib Khan, Hafiz Muhammad Ishaq

Abstract:

The Babesia gradually attained resistance against the synthetic medicines. To overcome the drug resistance, herbal therapy has gained more attention as compared to allopathic therapy. Peganumharmala (harmal) is a plant which has shown effective results against various protozoal diseases. Therefore, the present study was planned to monitor the efficacy of Peganumharmala (aqueous extract) against Babesiosis in cattle. For this purpose, a total of forty (n=40) infected animals were randomly divided into four equal groups (A, B, C, and D). Group A was treated with aqueous extract of Peganum harmala at 7.5 mg/kg, group B at 10 mg/kg and group C at 12.5 mg/kg of body weight. Group D served as a control group (normal). It was observed that there was a stabilization in hematological parameters (white and red blood cells, hemoglobin and Packed cell volume) in infected animals treated with Peganum harmala at different doses. Results of this study hence indicated that Peganum harmala extract at 12.5mg/kg BW is more effective against Babesiosis than lower doses.

Keywords: Babesiosis, cattle, control, Peganum harmala

Procedia PDF Downloads 284
4601 Isolation and Classification of Red Blood Cells in Anemic Microscopic Images

Authors: Jameela Ali Alkrimi, Abdul Rahim Ahmad, Azizah Suliman, Loay E. George

Abstract:

Red blood cells (RBCs) are among the most commonly and intensively studied type of blood cells in cell biology. The lack of RBCs is a condition characterized by lower than normal hemoglobin level; this condition is referred to as 'anemia'. In this study, a software was developed to isolate RBCs by using a machine learning approach to classify anemic RBCs in microscopic images. Several features of RBCs were extracted using image processing algorithms, including principal component analysis (PCA). With the proposed method, RBCs were isolated in 34 second from an image containing 18 to 27 cells. We also proposed that PCA could be performed to increase the speed and efficiency of classification. Our classifier algorithm yielded accuracy rates of 100%, 99.99%, and 96.50% for K-nearest neighbor (K-NN) algorithm, support vector machine (SVM), and neural network ANN, respectively. Classification was evaluated in highly sensitivity, specificity, and kappa statistical parameters. In conclusion, the classification results were obtained for a short time period with more efficient when PCA was used.

Keywords: red blood cells, pre-processing image algorithms, classification algorithms, principal component analysis PCA, confusion matrix, kappa statistical parameters, ROC

Procedia PDF Downloads 405
4600 Trans-Sphenoidal Approach to Pituitary Tumors: Analysis of 568 Cases Over a Decade

Authors: Sandeep Mohindra

Abstract:

Since 2013, the authors have operated on 568 cases of pituitary tumors through the trans-sphenoidal route, using the binostril approach. The distribution included 486 cases of non-functioning pituitary tumors, 24 cases of Growth hormone(GH) secreting tumors(acromegaly), and 28 cases of adrenocorticotrophic(ACTH) secreting tumors(Cushing's Disease). The authors utilized neuro-navigation for 18 cases, and all belonged to the functional tumor category. Complications included ICA injury in 2 cases, fatal meningitis in 5 cases, while CSF leak required repair in 28 cases. Satisfactory excision was noted in 512 cases, while recurrence/residual required repeat surgery in 32 cases. Authors conclude that trans sphenoidal route remains the best and optimal way of managing sellar tumors, especially pituitary adenomas.

Keywords: pituitary, adenoma, trans-sphenoidal, endonasal, neuronavigation

Procedia PDF Downloads 63
4599 Introduction of the Fluid-Structure Coupling into the Force Analysis Technique

Authors: Océane Grosset, Charles Pézerat, Jean-Hugh Thomas, Frédéric Ablitzer

Abstract:

This paper presents a method to take into account the fluid-structure coupling into an inverse method, the Force Analysis Technique (FAT). The FAT method, also called RIFF method (Filtered Windowed Inverse Resolution), allows to identify the force distribution from local vibration field. In order to only identify the external force applied on a structure, it is necessary to quantify the fluid-structure coupling, especially in naval application, where the fluid is heavy. This method can be decomposed in two parts, the first one consists in identifying the fluid-structure coupling and the second one to introduced it in the FAT method to reconstruct the external force. Results of simulations on a plate coupled with a cavity filled with water are presented.

Keywords: aeroacoustics, fluid-structure coupling, inverse methods, naval, turbulent flow

Procedia PDF Downloads 519