Search results for: rainfall temporal pattern
2075 Effect of Gas Boundary Layer on the Stability of a Radially Expanding Liquid Sheet
Authors: Soumya Kedia, Puja Agarwala, Mahesh Tirumkudulu
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Linear stability analysis is performed for a radially expanding liquid sheet in the presence of a gas medium. A liquid sheet can break up because of the aerodynamic effect as well as its thinning. However, the study of the aforementioned effects is usually done separately as the formulation becomes complicated and is difficult to solve. Present work combines both, aerodynamic effect and thinning effect, ignoring the non-linearity in the system. This is done by taking into account the formation of the gas boundary layer whilst neglecting viscosity in the liquid phase. Axisymmetric flow is assumed for simplicity. Base state analysis results in a Blasius-type system which can be solved numerically. Perturbation theory is then applied to study the stability of the liquid sheet, where the gas-liquid interface is subjected to small deformations. The linear model derived here can be applied to investigate the instability for sinuous as well as varicose modes, where the former represents displacement in the centerline of the sheet and the latter represents modulation in sheet thickness. Temporal instability analysis is performed for sinuous modes, which are significantly more unstable than varicose modes, for a fixed radial distance implying local stability analysis. The growth rates, measured for fixed wavenumbers, predicated by the present model are significantly lower than those obtained by the inviscid Kelvin-Helmholtz instability and compare better with experimental results. Thus, the present theory gives better insight into understanding the stability of a thin liquid sheet.Keywords: boundary layer, gas-liquid interface, linear stability, thin liquid sheet
Procedia PDF Downloads 2292074 Spatio-temporal Variations in Heavy Metal Concentrations in Sediment of Qua Iboe River Estuary, Nigeria
Authors: Justina I. R. Udotong, Ime R. Udotong, Offiong U. Eka
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The concentrations of heavy metals in sediments of Qua Iboe River Estuary (QIRE) were monitored at four different sampling locations in wet and dry seasons. A preliminary survey to determine the four sampling stations along the river continuum showed that the area spanned between < 0.1% salinity at the control station and 21.5‰ at the fourth station along the river continuum. A preliminary survey to determine the four sampling locations along the river estuary showed variations in salinity and other physicochemical parameters. The estuary was found to be polluted with heavy metals from point and nonpoint sources at varying degrees. Mean values of 7.80 mg/kg, 4.97 mg/kg and 2.80 mg/kg of nickel were obtained for sediment samples from Douglas creek, Qua Iboe and Atlantic sampling locations, respectively in the dry season. The wet season nickel concentrations were however lower. The entire study area was grossly contaminated by iron. At Douglas creek, the concentration of iron in sediment was 9274 ± 9.54 mg/kg while copper, nickel, lead and vanadium were <0.5 mg/kg each as compared to iron. Bioaccumulation was therefore suspected within the study area as values of 31.00 ± 0.79, 36.00 ± 0.10 and 55.00 ± 0.05 mg/kg of zinc were recorded in sediment at Douglas creek, Atlantic and the control sampling locations. The results from this study showed that the source of these heavy metals were from point sources like the corrosion of metal steel pipes from old bridges as well as oily sludge wastes from the Qua Iboe Terminal / tank farm located within the vicinity of the study area.Keywords: heavy metal, Qua Iboe River estuary, seasonal variations, Sediment
Procedia PDF Downloads 3712073 Enhancing Metaverse Security: A Multi-Factor Authentication Scheme
Authors: R. Chinnaiyaprabhu, S. Bharanidharan, V. Dharsana, Rajalavanya
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The concept of the Metaverse represents a potential evolution in the realm of cyberspace. In the early stages of Web 2.0, we observed a proliferation of online pseudonyms or 'nyms,' which increased the prevalence of fake accounts and made it challenging to establish unique online identities for various roles. However, in the era of Web 3.0, particularly in the context of the Metaverse, an individual's digital identity is intrinsically linked to their real-world identity. Consequently, actions taken in the Metaverse can carry significant consequences in the physical world. In light of these considerations, we propose the development of an innovative authentication system known as 'Metasec.' This system is designed to enhance security for digital assets, online identities, avatars, and user accounts within the Metaverse. Notably, Metasec operates as a password less authentication solution, relying on a multifaceted approach to security, encompassing device attestation, facial recognition, and pattern-based security keys.Keywords: metaverse, multifactor authentication, security, facial recognition, patten password
Procedia PDF Downloads 672072 Green Prossesing of PS/Nanoparticle Fibers and Studying Morphology and Properties
Authors: M. Kheirandish, S. Borhani
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In this experiment Polystyrene/Zinc-oxide (PS/ZnO) nanocomposite fibers were produced by electrospinning technique using limonene as a green solvent. First, the morphology of electrospun pure polystyrene (PS) and PS/ZnO nanocomposite fibers investigated by SEM. Results showed the PS fiber diameter decreased by increasing concentration of Zinc Oxide nanoparticles (ZnO NPs). Thermo Gravimetric Analysis (TGA) results showed thermal stability of nanocomposites increased by increasing ZnO NPs in PS electrospun fibers. Considering Differential Scanning Calorimeter (DSC) thermograms for electrospun PS fibers indicated that introduction of ZnO NPs into fibers affects the glass transition temperature (Tg) by reducing it. Also, UV protection properties of nanocomposite fibers were increased by increasing ZnO concentration. Evaluating the effect of metal oxide NPs amount on mechanical properties of electrospun layer showed that tensile strength and elasticity modulus of the electrospun layer of PS increased by addition of ZnO NPs. X-ray diffraction (XRD) pattern of nanopcomposite fibers confirmed the presence of NPs in the samples.Keywords: electrospininng, nanoparticle, polystyrene, ZnO
Procedia PDF Downloads 2412071 Prevalence, Antimicrobial Susceptibility Pattern and Public Health Significance for Staphylococcus Aureus of Isolated from Raw Red Meat at Butchery and Abattoir House in Mekelle, Northern Ethiopia
Authors: Haftay Abraha Tadesse
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Background: Staphylococcus is a genus of worldwide distributed bacteria correlated to several infectious of different sites in humans and animals. They are among the most important causes of infection that are associated with the consumption of contaminated food. Objective: The objective of this study was to determine the isolates, antimicrobial susceptibility patterns and Public Health Significance of Staphylococcus aureus in raw meat from butchery and abattoir houses of Mekelle, Northern Ethiopia. Methodology: A cross-sectional study was conducted from April to October 2019. Socio-demographic data and Public Health Significance were collected using a predesigned questionnaire. The raw meat samples were collected aseptically in the butchery and abattoir houses and transported using an ice box to Mekelle University, College of Veterinary Sciences, for isolating and identification of Staphylococcus aureus. Antimicrobial susceptibility tests were determined by the disc diffusion method. Data obtained were cleaned and entered into STATA 22.0 and a logistic regression model with odds ratio was calculated to assess the association of risk factors with bacterial contamination. A P-value < 0.05 was considered statistically significant. Results: In the present study, 88 out of 250 (35.2%) were found to be contaminated with Staphylococcus aureus. Among the raw meat specimens, the positivity rate of Staphylococcus aureus was 37.6% (n=47) and (32.8% (n=41), butchery and abattoir houses, respectively. Among the associated risks, factories not using gloves reduces risk was found to (AOR=0.222; 95% CI: 0.104-0.473), Strict Separation b/n clean & dirty (AOR= 1.37; 95% CI: 0.66-2.86) and poor habit of hand washing (AOR=1.08; 95%CI: 0.35 3.35) was found to be statistically significant and have associated with Staphylococcus aureus contamination. All isolates of thirty-seven of Staphylococcus aureus were checked and displayed (100%) sensitive to doxycycline, trimethoprim, gentamicin, sulphamethoxazole, amikacin, CN, Co trimoxazole and nitrofurantoi. Whereas the showed resistance to cefotaxime (100%), ampicillin (87.5%), Penicillin (75%), B (75%), and nalidixic acid (50%) from butchery houses. On the other hand, all isolates of Staphylococcus aureus isolate 100% (n= 10) showed sensitive chloramphenicol, gentamicin and nitrofurantoin, whereas they showed 100% resistance of Penicillin, B, AMX, ceftriaxone, ampicillin and cefotaxime from abattoirs houses. The overall multi-drug resistance pattern for Staphylococcus aureus was 90% and 100% of butchery and abattoir houses, respectively. Conclusion: 35.3% Staphylococcus aureus isolated were recovered from the raw meat samples collected from the butchery and abattoirs houses. More has to be done in the development of hand washing behavior and availability of safe water in the butchery houses to reduce the burden of bacterial contamination. The results of the present finding highlight the need to implement protective measures against the levels of food contamination and alternative drug options. The development of antimicrobial resistance is nearly always a result of repeated therapeutic and/or indiscriminate use of them. Regular antimicrobial sensitivity testing helps to select effective antibiotics and to reduce the problems of drug resistance development towards commonly used antibiotics.Keywords: abattoir house, AMR, butchery house, S. aureus
Procedia PDF Downloads 982070 The Multi-Lingual Acquisition Patterns of Elementary, High School and College Students in Angeles City, Philippines
Authors: Dennis Infante, Leonora Yambao
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The Philippines is a multilingual community. A Filipino learns at least three languages throughout his lifespan. Since languages are learned and picked up simultaneously in the environment, a student naturally develops a language system that combines features of at least three languages: the local language, English and Filipino. This study seeks to investigate this particular phenomenon and aspires to propose a theoretical framework of unique language acquisition in the elementary, high school and college in the three languages spoken and used in media, community, business and school: Kapampangan, the local language; Filipino, the national language; and English. The study randomly selects five students from three participating schools in order to acquire language samples. The samples were analyzed in the subsentential, sentential and suprasentential levels using grammatical theories. The data are classified to map out the pattern of substitution or shifting from one language to another.Keywords: language acquisition, mother tongue, multiculturalism, multilingual education
Procedia PDF Downloads 3802069 Looking for a Connection between Oceanic Regions with Trends in Evaporation with Continental Ones with Trends in Precipitation through a Lagrangian Approach
Authors: Raquel Nieto, Marta Vázquez, Anita Drumond, Luis Gimeno
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One of the hot spots of climate change is the increment of ocean evaporation. The best estimation of evaporation, OAFlux data, shows strong increasing trends in evaporation from the oceans since 1978, with peaks during the hemispheric winter and strongest along the paths of the global western boundary currents and any inner Seas. The transport of moisture from oceanic sources to the continents is the connection between evaporation from the ocean and precipitation over the continents. A key question is to try to relate evaporative source regions over the oceans where trends have occurred in the last decades with their sinks over the continents to check if there have been also any trends in the precipitation amount or its characteristics. A Lagrangian approach based on FLEXPART and ERA-interim data is used to establish this connection. The analyzed period was 1980 to 2012. Results show that there is not a general pattern, but a significant agreement was found in important areas of climate interest.Keywords: ocean evaporation, Lagrangian approaches, contiental precipitation, Europe
Procedia PDF Downloads 2562068 Non-linear Analysis of Spontaneous EEG After Spinal Cord Injury: An Experimental Study
Authors: Jiangbo Pu, Hanhui Xu, Yazhou Wang, Hongyan Cui, Yong Hu
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Spinal cord injury (SCI) brings great negative influence to the patients and society. Neurological loss in human after SCI is a major challenge in clinical. Instead, neural regeneration could have been seen in animals after SCI, and such regeneration could be retarded by blocking neural plasticity pathways, showing the importance of neural plasticity in functional recovery. Here we used sample entropy as an indicator of nonlinear dynamical in the brain to quantify plasticity changes in spontaneous EEG recordings of rats before and after SCI. The results showed that the entropy values were increased after the injury during the recovery in one week. The increasing tendency of sample entropy values is consistent with that of behavioral evaluation scores. It is indicated the potential application of sample entropy analysis for the evaluation of neural plasticity in spinal cord injury rat model.Keywords: spinal cord injury (SCI), sample entropy, nonlinear, complex system, firing pattern, EEG, spontaneous activity, Basso Beattie Bresnahan (BBB) score
Procedia PDF Downloads 4652067 Iran’s Dual Geopolitical Approach towards African States
Authors: Dragos Ardeleanu, Silviu-Valentin Petre
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Written to satisfy the needs of Western powers, classical geopolitics bore the stint of Eurocentrism. Both Mackinder’s heartland and Nicholas Spykman’s rimland were intellectual creations set for the purpose of the Anglophone nations dealing with Eurasia. However, while today’s world is moving towards multipolarity, other emerging regional actors are following their own interests using a different geospatial map. Such is the case of Iran which has developed an engagement pattern in Africa, directed mostly towards costal states, in order to break the rimland grip of Arab states and also the international pressure established against Tehran’s nascent nuclear program. Capitalizing on literature review and analysing statements from key public figures, our paper argues that Iranian African geopolitics displays a dual message: on the one hand, it uses tiers-mondiste rhetoric to garner the support of different coastal African states and, on the other hand, it employs Shiism to gain a foothold in strategic parts of the black continent.Keywords: African geopolitics, Iran, Shiism, tiers-mondisme
Procedia PDF Downloads 2172066 Right Solution of Geodesic Equation in Schwarzschild Metric and Overall Examination of Physical Laws
Authors: Kwan U. Kim, Jin Sim, Ryong Jin Jang, Sung Duk Kim
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108 years have passed since a great number of physicists explained astronomical and physical phenomena by solving geodesic equations in the Schwarzschild metric. However, when solving the geodesic equations in Schwarzschild metric, they did not correctly solve one branch of the component of space among spatial and temporal components of four-dimensional force and did not come up with physical laws correctly by means of physical analysis from the results obtained by solving the geodesic equations. In addition, they did not treat the astronomical and physical phenomena in a physical way based on the correct physical laws obtained from the solution of the geodesic equations in the Schwarzschild metric. Therefore, some former scholars mentioned that Einstein’s theoretical basis of a general theory of relativity was obscure and incorrect, but they did not give a correct physical solution to the problems. Furthermore, since the general theory of relativity has not given a quantitative solution to obscure and incorrect problems, the generalization of gravitational theory has not yet been successfully completed, although former scholars have thought of it and tried to do it. In order to solve the problems, it is necessary to explore the obscure and incorrect problems in a general theory of relativity based on the physical laws and to find out the methodology for solving the problems. Therefore, as the first step toward achieving this purpose, the right solution of the geodesic equation in the Schwarzschild metric has been presented. Next, the correct physical laws found by making a physical analysis of the results have been presented, the obscure and incorrect problems have been shown, and an analysis of them has been made based on the physical laws. In addition, the experimental verification of the physical laws found by us has been made.Keywords: equivalence principle, general relativity, geometrodynamics, Schwarzschild, Poincaré
Procedia PDF Downloads 142065 Growth Mechanism, Structural and Compositional Properties of Cu₂ZnSnS₄ (CZTS) Thin Films Deposited by Sputtering Method from a Compound Target
Authors: Sanusi Abdullahi, Musa Momoh, Abubakar Umar Moreh, Aminu Muhammad Bayawa, Olubunmi Popoola
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Kesterite-type Cu₂ZnSnS₄ (CZTS) thin films were deposited on corning glass from a single quaternary target. In this study, we investigated the growth mechanism and the influence of thin film thickness on the structural and compositional properties of CZTS films. All the four samples (as-deposited inclusive) show peaks corresponding to kesterite-type structure. The diffraction peaks of (112) are sharp and the small characteristics peaks of the kesterite structure such as (220)/ (204) and (312)/ (116) are also clearly observed in X-ray diffraction pattern. These results indicate that the quaternary CZTS would be a potential candidate for solar cell applications.Keywords: RF sputtering, Cu2ZnSnS4 thin film, annealing, growth mechanism, annealing, growth mechanism, renewable energy
Procedia PDF Downloads 3732064 Exploring the Effects of Transcendental Mindfulness Meditation on Anxiety Symptoms in Young Females
Authors: Claudia Cedeno Nadal, Mei-Ling Villafana, Griela Rodriguez, Jessica Martin, Jennifer Martin, Megan Patel
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This study systematically examines the impact of Transcendental Mindfulness Meditation on anxiety symptoms in young females aged 18-25. Through a comprehensive literature review, we found consistent evidence supporting the positive influence of Transcendental Mindfulness Meditation on reducing anxiety, enhancing overall well-being, and decreasing perceived stress levels within this demographic. The mechanisms underlying these effects include heightened self-awareness, improved emotional regulation, and the development of effective stress-coping strategies. These findings have significant implications for mental health interventions targeting young females. However, the reviewed studies had some limitations, such as small sample sizes and reliance on self-report measures. To advance this field, future research should focus on larger sample sizes and utilize a broader range of measurement methods, including neuroscience assessments. Additionally, investigating the temporal relationships between Transcendental Mindfulness Meditation, proposed mediators, and anxiety symptoms will help establish causal specificity and a deeper understanding of the precise mechanisms of action. The development of integrative models based on these mechanisms can further enhance the effectiveness of Transcendental Mindfulness Meditation as an intervention for anxiety in this demographic. This study contributes to the current knowledge on the potential benefits of Transcendental Mindfulness Meditation for reducing anxiety in young females, paving the way for more targeted and effective mental health interventions in this population.Keywords: mindfulness, meditation, anxiety, transcendental mindfulness
Procedia PDF Downloads 702063 Anodization-Assisted Synthesis of Shape-Controlled Cubic Zirconia Nanotubes
Authors: Ibrahim Dauda Muhammad, Mokhtar Awang
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To synthesize a specific phase of zirconia (ZrO₂) nanotubes, zirconium (Zr) foil was subjected to the anodization process in a fluorine-containing electrochemical bath for a fixed duration. The resulting zirconia nanotubes (ZNTs) were then characterized using various techniques, including UV-vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The XRD diffraction pattern confirmed that the ZNTs were crystalline, with a predominant texture along the [111] direction, indicating that the majority of the phase was cubic. TEM images revealed that most of the nanotubes were vertically aligned and self-organized, with diameters ranging from 32.9 to 38.8 nm and wall thicknesses between 3.0 and 7.3 nm. Additionally, the synthesized ZNTs had a length-to-width ratio of 235, which closely matches the ratio of 240 observed in another study where anodization was not used. This study demonstrates that a specific phase of zirconia nanotube can be successfully synthesized, with promising potential applications in catalysis and other areas.Keywords: zirconia nanotubes, anodization, characterization, cubic phase
Procedia PDF Downloads 182062 Short-Term versus Long-Term Effect of Waterpipe Smoking Exposure on Cardiovascular Biomarkers in Mice
Authors: Abeer Rababa'h, Ragad Bsoul, Mohammad Alkhatatbeh, Karem Alzoubi
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Introduction: Tobacco use is one of the main risk factors to cardiovascular diseases (CVD) and atherosclerosis in particular. WPS contains several toxic materials such as: nicotine, carcinogens, tar, carbon monoxide and heavy metals. Thus, WPS is considered to be as one of the toxic environmental factors that should be investigated intensively. Therefore, the aim of this study is to investigate the effect of WPS on several cardiovascular biological markers that may cause atherosclerosis in mice. The study also conducted to study the temporal effects of WPS on the atherosclerotic biomarkers upon short (2 weeks) and long-term (8 weeks) exposures. Methods: mice were exposed to WPS and heart homogenates were analyzed to elucidate the effects of WPS on matrix metalloproteinase (MMPs), endothelin-1 (ET-1) and, myeloperoxidase (MPO). Following protein estimation, enzyme-linked immunosorbent assays were done to measure the levels of MMPs (isoforms 1, 3, and 9), MPO, and ET-1 protein expressions. Results: our data showed that acute exposure to WPS significantly enhances the levels of MMP-3, MMP- 9, and MPO expressions (p < 0.05) compared to their corresponding control. However, the body was capable to normalize the level of expressions for such parameters following continuous exposure for 8 weeks (p > 0.05). Additionally, we showed that the level of ET-1 expression was significantly higher upon chronic exposure to WPS compared to both control and acute exposure groups (p < 0.05). Conclusion: Waterpipe exposure has a significant negative effect on atherosclerosis and the enhancement of the atherosclerotic biomarkers expression (MMP-3 and 9, MPO, and ET-1) might represent an early scavenger of compensatory efforts to maintain cardiac function after WP exposure.Keywords: atherosclerotic biomarkers, cardiovascular disease, matrix metalloproteinase, waterpipe
Procedia PDF Downloads 3522061 Speedup Breadth-First Search by Graph Ordering
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Breadth-First Search(BFS) is a core graph algorithm that is widely used for graph analysis. As it is frequently used in many graph applications, improve the BFS performance is essential. In this paper, we present a graph ordering method that could reorder the graph nodes to achieve better data locality, thus, improving the BFS performance. Our method is based on an observation that the sibling relationships will dominate the cache access pattern during the BFS traversal. Therefore, we propose a frequency-based model to construct the graph order. First, we optimize the graph order according to the nodes’ visit frequency. Nodes with high visit frequency will be processed in priority. Second, we try to maximize the child nodes overlap layer by layer. As it is proved to be NP-hard, we propose a heuristic method that could greatly reduce the preprocessing overheads. We conduct extensive experiments on 16 real-world datasets. The result shows that our method could achieve comparable performance with the state-of-the-art methods while the graph ordering overheads are only about 1/15.Keywords: breadth-first search, BFS, graph ordering, graph algorithm
Procedia PDF Downloads 1382060 Characterization of Surface Microstructures on Bio-Based PLA Fabricated with Nano-Imprint Lithography
Authors: D. Bikiaris, M. Nerantzaki, I. Koliakou, A. Francone, N. Kehagias
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In the present study, the formation of structures in poly(lactic acid) (PLA) has been investigated with respect to producing areas of regular, superficial features with dimensions comparable to those of cells or biological macromolecules. Nanoimprint lithography, a method of pattern replication in polymers, has been used for the production of features ranging from tens of micrometers, covering areas up to 1 cm², down to hundreds of nanometers. Both micro- and nano-structures were faithfully replicated. Potentially, PLA has wide uses within biomedical fields, from implantable medical devices, including screws and pins, to membrane applications, such as wound covers, and even as an injectable polymer for, for example, lipoatrophy. The possibility of fabricating structured PLA surfaces, with structures of the dimensions associated with cells or biological macro- molecules, is of interest in fields such as cellular engineering. Imprint-based technologies have demonstrated the ability to selectively imprint polymer films over large areas resulting in 3D imprints over flat, curved or pre-patterned surfaces. Here, we compare nano-patterned with nano-patterned by nanoimprint lithography (NIL) PLA film. A silicon nanostructured stamp (provided by Nanotypos company) having positive and negative protrusions was used to pattern PLA films by means of thermal NIL. The polymer film was heated from 40°C to 60°C above its Tg and embossed with a pressure of 60 bars for 3 min. The stamp and substrate were demolded at room temperature. Scanning electron microscope (SEM) images showed good replication fidelity of the replicated Si stamp. Contact-angle measurements suggested that positive microstructuring of the polymer (where features protrude from the polymer surface) produced a more hydrophilic surface than negative micro-structuring. The ability to structure the surface of the poly(lactic acid), allied to the polymer’s post-processing transparency and proven biocompatibility. Films produced in this were also shown to enhance the aligned attachment behavior and proliferation of Wharton’s Jelly Mesenchymal Stem cells, leading to the observed growth contact guidance. The bacterial attachment patterns of some bacteria, highlighted that the nano-patterned PLA structure can reduce the propensity for the bacteria to attach to the surface, with a greater bactericidal being demonstrated activity against the Staphylococcus aureus cells. These biocompatible, micro- and nanopatterned PLA surfaces could be useful for polymer– cell interaction experiments at dimensions at, or below, that of individual cells. Indeed, post-fabrication modification of the microstructured PLA surface, with materials such as collagen (which can further reduce the hydrophobicity of the surface), will extend the range of applications, possibly through the use of PLA’s inherent biodegradability. Further study is being undertaken to examine whether these structures promote cell growth on the polymer surface.Keywords: poly(lactic acid), nano-imprint lithography, anti-bacterial properties, PLA
Procedia PDF Downloads 3302059 Orthosis and Finite Elements: A Study for Development of New Designs through Additive Manufacturing
Authors: M. Volpini, D. Alves, A. Horta, M. Borges, P. Reis
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The gait pattern in people that present motor limitations foment the demand for auxiliary locomotion devices. These artifacts for movement assistance vary according to its shape, size and functional features, following the clinical applications desired. Among the ortheses of lower limbs, the ankle-foot orthesis aims to improve the ability to walk in people with different neuromuscular limitations, although they do not always answer patients' expectations for their aesthetic and functional characteristics. The purpose of this study is to explore the possibility of using new design in additive manufacturer to reproduce the shape and functional features of a ankle-foot orthesis in an efficient and modern way. Therefore, this work presents a study about the performance of the mechanical forces through the analysis of finite elements in an ankle-foot orthesis. It will be demonstrated a study of distribution of the stress on the orthopedic device in orthostatism and during the movement in the course of patient's walk.Keywords: additive manufacture, new designs, orthoses, finite elements
Procedia PDF Downloads 2112058 Investigation Of The Catalyst's Effect On Nickel Sulfide Thin Films
Authors: Randa Slatnia
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In this study, the nanostructured stable phase identification elaborated by nickel nitrate hyxahydrate and thiourea compounds. After the preparation of the solution (Stirred mixture with methanol as solvent), a deposition of eight layers of this solution on a glass substrate and annealed at 300 °C for energy applications. The annealed sample was analyzed by X-ray Grazing incidence diffraction (GID) with a Bruker D8 Advance diffractometer using Cu Kα1 radiation at 40 kV and 40 mA (1600 W) and Scanning electron microscopy (Thermo Fisher environmental SEM). The results of XRD-GID analysis for the prepared sample showed the formation of an identified stable phase NiS2 and the XRD-GID pattern of the elaborated sample with eight layers prepared solution and annealed show wide and characteristic peaks of the NiS2 with cubic structure (ICDD card no. PDF 01-078-4702). The morphology of the NiS2 thin films confirmed by XRD-GID analysis was investigated by ESEM showed a surface with a uniform and homogeneous distribution nanostructure.Keywords: nickel sulfide, thin films, XRD, ESEM
Procedia PDF Downloads 832057 Drought Risk Analysis Using Neural Networks for Agri-Businesses and Projects in Lejweleputswa District Municipality, South Africa
Authors: Bernard Moeketsi Hlalele
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Drought is a complicated natural phenomenon that creates significant economic, social, and environmental problems. An analysis of paleoclimatic data indicates that severe and extended droughts are inevitable part of natural climatic circle. This study characterised drought in Lejweleputswa using both Standardised Precipitation Index (SPI) and neural networks (NN) to quantify and predict respectively. Monthly 37-year long time series precipitation data were obtained from online NASA database. Prior to the final analysis, this dataset was checked for outliers using SPSS. Outliers were removed and replaced by Expectation Maximum algorithm from SPSS. This was followed by both homogeneity and stationarity tests to ensure non-spurious results. A non-parametric Mann Kendall's test was used to detect monotonic trends present in the dataset. Two temporal scales SPI-3 and SPI-12 corresponding to agricultural and hydrological drought events showed statistically decreasing trends with p-value = 0.0006 and 4.9 x 10⁻⁷, respectively. The study area has been plagued with severe drought events on SPI-3, while on SPI-12, it showed approximately a 20-year circle. The concluded the analyses with a seasonal analysis that showed no significant trend patterns, and as such NN was used to predict possible SPI-3 for the last season of 2018/2019 and four seasons for 2020. The predicted drought intensities ranged from mild to extreme drought events to come. It is therefore recommended that farmers, agri-business owners, and other relevant stakeholders' resort to drought resistant crops as means of adaption.Keywords: drought, risk, neural networks, agri-businesses, project, Lejweleputswa
Procedia PDF Downloads 1262056 A Sharp Interface Model for Simulating Seawater Intrusion in the Coastal Aquifer of Wadi Nador (Algeria)
Authors: Abdelkader Hachemi, Boualem Remini
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Seawater intrusion is a significant challenge faced by coastal aquifers in the Mediterranean basin. This study aims to determine the position of the sharp interface between seawater and freshwater in the aquifer of Wadi Nador, located in the Wilaya of Tipaza, Algeria. A numerical areal sharp interface model using the finite element method is developed to investigate the spatial and temporal behavior of seawater intrusion. The aquifer is assumed to be homogeneous and isotropic. The simulation results are compared with geophysical prospection data obtained through electrical methods in 2011 to validate the model. The simulation results demonstrate a good agreement with the geophysical prospection data, confirming the accuracy of the sharp interface model. The position of the sharp interface in the aquifer is found to be approximately 1617 meters from the sea. Two scenarios are proposed to predict the interface position for the year 2024: one without pumping and the other with pumping. The results indicate a noticeable retreat of the sharp interface position in the first scenario, while a slight decline is observed in the second scenario. The findings of this study provide valuable insights into the dynamics of seawater intrusion in the Wadi Nador aquifer. The predicted changes in the sharp interface position highlight the potential impact of pumping activities on the aquifer's vulnerability to seawater intrusion. This study emphasizes the importance of implementing measures to manage and mitigate seawater intrusion in coastal aquifers. The sharp interface model developed in this research can serve as a valuable tool for assessing and monitoring the vulnerability of aquifers to seawater intrusion.Keywords: seawater intrusion, sharp interface, coastal aquifer, algeria
Procedia PDF Downloads 1202055 The Application of Bayesian Heuristic for Scheduling in Real-Time Private Clouds
Authors: Sahar Sohrabi
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The emergence of Cloud data centers has revolutionized the IT industry. Private Clouds in specific provide Cloud services for certain group of customers/businesses. In a real-time private Cloud each task that is given to the system has a deadline that desirably should not be violated. Scheduling tasks in a real-time private CLoud determine the way available resources in the system are shared among incoming tasks. The aim of the scheduling policy is to optimize the system outcome which for a real-time private Cloud can include: energy consumption, deadline violation, execution time and the number of host switches. Different scheduling policies can be used for scheduling. Each lead to a sub-optimal outcome in a certain settings of the system. A Bayesian Scheduling strategy is proposed for scheduling to further improve the system outcome. The Bayesian strategy showed to outperform all selected policies. It also has the flexibility in dealing with complex pattern of incoming task and has the ability to adapt.Keywords: cloud computing, scheduling, real-time private cloud, bayesian
Procedia PDF Downloads 3592054 Measuring the Effect of Continuous Performance Test-3 Administration on Regional Cerebral Blood Flow with Single-Photon Emission Computed Tomography in Adult ADHD
Authors: Claire Stafford, Charles Golden, Daniel Amen, Kristen Willeumier
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The aim of this study is to investigate the effect of the administration of the Conners Continuous Performance Test (CPT-3) on cerebral blood flow (CBF) in adults with ADHD. The data for this study was derived from a large SPECT database. Participants in the ADHD group (n=81, Mage=37.97) were similar to those in the healthy control group (n=8503, Mage=41.86). All participants were assessed for cerebral blood flow levels before and after CPT-3 administration. Both age and gender were considered covariates. Multiple 2-by-2 ANCOVAs with repeated measures were conducted with sphericity assumed. The main effects of CPT-3 administration on CBF levels were significant in the left and right side of the frontal and occipital, and right temporal lobe. The main effects of ADHD diagnosis were significant in all brain areas assessed. The interaction between CPT-3 administration and ADHD diagnosis was significant in the left and right side of the limbic system, basal ganglia, the frontal lobe, and occipital lobe. Post hoc tests with a Bonferroni adjustment revealed that CBF levels increased following CPT-3 administration but less so in the ADHD group. Individuals had higher levels of CBF following the administration of CPT-3. Due to a significant interaction, we can infer that ADHD diagnosis changes the effect of CPT-3 administration on CBF levels. This is consistent with our hypothesis considering that CPT-3 is a test of sustained attention, a common challenge for children with ADHD. The aforementioned interaction was not found to be significant in the parietal lobe. This may be due to the nature of CPT- 3 which does not require an integration of sensory information.Keywords: SPECT, ADHD, conners continuous performance test, cerebral blood flow
Procedia PDF Downloads 1022053 Fertilizer Value of Nitrogen Captured from Poultry Facilities Using Ammonia Scrubbers
Authors: Philip A. Moore Jr., Jerry Martin, Hong Li
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Research has shown that over half of the nitrogen (N) excreted from broiler chickens is emitted to the atmosphere before the manure is removed from the barns, resulting in air and water pollution, as well as the loss of a valuable fertilizer resource. The objective of this study was to determine the fertilizer efficiency of N captured from the exhaust air from poultry houses using acid scrubbers. This research was conducted using 24 plots located on a Captina silt loam soil. There were six treatments: (1) unfertilized control, (2) aluminum sulfate (alum) scrubber solution, (3) potassium bisulfate scrubber solution, (4) sodium bisulfate scrubber solution, (5) sulfuric acid scrubber solution and (6) ammonium nitrate fertilizer dissolved in water. There were four replications per treatment in a randomized block design. The scrubber solutions were obtained from acid scrubbers attached to exhaust fans on commercial broiler houses. All N sources were applied at an application rate equivalent to 112 kg N ha⁻¹. Forage yields were measured five times throughout the growing season. Five months after the fertilizer sources were applied, a rainfall simulation study was conducted to determine the potential effects on phosphorus (P) runoff. Forage yields were significantly higher in plots fertilized with scrubber solutions from potassium bisulfate and sodium bisulfate than plots fertilized with scrubber solutions made from alum or sulfuric acid or ammonium nitrate, which were higher than the controls (7.61, 7.46, 6.87, 6.72, 6.45, and 5.12 Mg ha ⁻¹, respectively). Forage N uptake followed similar trends as yields. Phosphorus runoff and water soluble P was significantly lower in plots fertilized with the scrubber solutions made from aluminum sulfate. This study demonstrates that N captured using ammonia scrubbers is as good or possibly better than commercial ammonium nitrate fertilizer.Keywords: air quality, ammonia emissions, nitrogen fertilizer, poultry
Procedia PDF Downloads 2002052 “Fake It Till You Make It”: A Qualitative Study into the Well-being of Autistic Women
Authors: Kathleen Seers, Rachel Hogg
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Diagnosis of Autism Spectrum Disorder (ASD) in women is increasing, prompting research into the presentation of female ASD and exploring why females are failing to meet the diagnostic threshold. One explanation is the use of masking behaviors, where traits of ASD are suppressed and gender-appropriate behaviors are mimicked to reduce the visibility and victimization of ASD girls. Current research explores ASD presentation and the lived experiences of ASD girls and adolescents; however, there is a paucity of literature in relation to the intra- and inter- psychic experiences of ASD women. Through a social constructionist framework, this qualitative study sought to understand how the construction of gender and the medicalisation of ASD influences women’s experiences of ASD. This study also explored the use and consequence of masking strategies and the impact this has on well-being. Eight women were interviewed, and three major themes were identified. The themes outline the influence of gender expectations and social norms on the women’s experiences, the significance of diagnosis to their identity, and the influence of the medicalization of ASD. Participants shared experiences of feeling different and internalizing blame for this difference. The feeling of difference was a major contributor to the women’s positive or negative mental well-being. The process of diagnosis allowed participants to create and confirm their identity. Diagnosis also led to improvements in well-being, however, the findings also explore the complexity of labeling individuals with a disorder and the difficulties that arise from the construct of ‘functionality’ for those with Autism. The study also explores the temporal nature of ASD and the changing experiences of women as they mature. It is hoped this study promotes discussion and provides clinicians and those connected to ASD women with insights into the support ASD women require to live authentic lives.Keywords: female autism, gender, masking, social constructionism
Procedia PDF Downloads 1212051 Small Wind Turbine Hybrid System for Remote Application: Egyptian Case Study
Authors: M. A. Badr, A. N. Mohib, M. M. Ibrahim
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The objective of this research is to study the technical and economic performance of wind/diesel/battery (W/D/B) system supplying a remote small gathering of six families using HOMER software package. The electrical energy is to cater for the basic needs for which the daily load pattern is estimated. Net Present Cost (NPC) and Cost of Energy (COE) are used as economic criteria, while the measure of performance is % of power shortage. Technical and economic parameters are defined to estimate the feasibility of the system under study. Optimum system configurations are estimated for two sites. Using HOMER software, the simulation results showed that W/D/B systems are economical for the assumed community sites as the price of generated electricity is about 0.308 $/kWh, without taking external benefits into considerations. W/D/B systems are more economical than W/B or diesel alone systems, as the COE is 0.86 $/kWh for W/B and 0.357 $/kWh for diesel alone.Keywords: optimum energy systems, remote electrification, renewable energy, wind turbine systems
Procedia PDF Downloads 4032050 Biodegradable and Bioactive Scaffold for Bone Tissue Engineering
Authors: A. M. Malagon Escandon, J. A. Arenas Alatorre, C. P. Chaires Rosas, N. A. Vazquez Torres, B. Hernandez Tellez, G. Pinon Zarate, M. Herrera Enriquez, A. E. Castell Rodriguez
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The current approach to the treatment of bone defects involves the use of scaffolds that provide a biological and mechanically stable niche to favor tissue repair. Despite the significant progress in the field of bone tissue engineering, several main problems associated are attributed to giving a low biodegradation degree, does not promote osseointegration and regeneration, if the bone is not healing as well as expected or fails to heal, will not be given a proper ossification or new bone formation. The actual approaches of bone tissue regeneration are directed to the use of decellularized native extracellular matrices, which are able of retain their own architecture, mechanic properties, biodegradability and promote new bone formation because they are capable of conserving proteins and other factors that are founded in physiological concentrations. Therefore, we propose an extracellular matrix-based bioscaffolds derived from bovine cancellous bone, which is processed by decellularization, demineralization, and hydrolysis of the collagen protein, these protocols have been successfully carried out in other organs and tissues; the effectiveness of its biosafety has also been previously evaluated in vivo and Food and Drug Administration (FDA) approved. In the specific case of bone, a more complex treatment is needed in comparison with other organs and tissues because is necessary demineralization and collagen denaturalization. The present work was made in order to obtain a temporal scaffold that succeed in degradation in an inversely proportional way to the synthesis of extracellular matrix and the maturation of the bone by the cells of the host.Keywords: bioactive, biodegradable, bone, extracellular matrix-based bioscaffolds, stem cells, tissue engineering
Procedia PDF Downloads 1582049 In vitro Antioxidant and Antibacterial Activities of Methanol Extracts of Tamus communis L. from Algeria
Authors: F. Belkhiri, A. Baghiani, S. Boumerfeg, N. Charef, S. Khennouf, L. Arrar
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The present study was conducted to evaluate the in vitro antioxidant and antibacterial properties of methanolic extracts from roots of Tamus communis L. (TCRE), which is a plant used in traditional medicine in Algeria. The antioxidant potential of pattern was evaluated using tow complementary techniques, inhibition of free radical DPPH and the test of β-Carotene/linoleic acid. The antioxidant test indicates that non-polar fractions of TCRE (chloroform and ethyl acetate fractions) were more active than the polar fractions. Among these fractions, the chloroform extract appear in the DPPH test an IC50 of (18.89 µg/ml) comparable to that of BHT (18.6 µg/ml). This fraction was able to inhibiting the oxidation of β-Carotene with a percentage of inhibition (89.84 %). In antibacterial test, non-polar fractions showed antibacterial activity very important compared with the polar fractions. These fractions have inhibited the growth of four from nine bacterial strains, causing zones of inhibition from 08 to 23 mm of diameter.Keywords: antioxidant activity, antibacterial activity, Tamus communis L., polar fractions
Procedia PDF Downloads 5872048 An Experimental Investigation of Air Entrainment Due to Water Jets in Crossflows
Authors: Mina Esmi Jahromi, Mehdi Khiadani
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Vertical water jets discharging into free surface turbulent cross flows result in the ingression of a large amount of air in the body of water and form a region of two-phase air-water flow with a considerable interfacial area. This research presents an experimental study of the two-phase bubbly flow using image processing technique. The air ingression and the trajectories of bubble swarms under different experimental conditions are evaluated. The rate of air entrainment and the bubble characteristics such as penetration depth, and dispersion pattern were found to be affected by the most influential parameters of water jet and cross flow including water jet-to-crossflow velocity ratio, water jet falling height, and cross flow depth. This research improves understanding of the underwater flow structure due to the water jet impingement in crossflow and advances the practical applications of water jets such as artificial aeration, circulation, and mixing where crossflow is present.Keywords: air entrainment, image processing, jet in cross flow, two-phase flow
Procedia PDF Downloads 3692047 An Experimental Quantitative Case Study of Competency-Based Learning in Online Mathematics Education
Authors: Pascal Roubides
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The presentation proposed herein describes a research case study of a hybrid application of the competency-based education model best exemplified by Western Governor’s University, within the general temporal confines of an accelerated (8-week) term of a College Algebra course at the author’s institution. A competency-based model was applied to an accelerated online College Algebra course, built as an Open Educational Resources (OER) course, seeking quantifiable evidence of any differences in the academic achievement of students enrolled in the competency-based course and the academic achievement of the current delivery of the same course. Competency-based learning has been gaining in support in recent times and the author’s institution has also been involved in its own efforts to design and develop courses based on this approach. However, it is unknown whether there had been any research conducted to quantify evidence of the effect of this approach against traditional approaches prior to the author’s case study. The research question sought to answer in this experimental quantitative study was whether the online College Algebra curriculum at the author’s institution delivered via an OER-based competency-based model can produce statistically significant improvement in retention and success rates against the current delivery of the same course. Results obtained in this study showed that there is no statistical difference in the retention rate of the two groups. However, there was a statistically significant difference found between the rates of successful completion of students in the experimental group versus those in the control group.Keywords: competency-based learning, online mathematics, online math education, online courses
Procedia PDF Downloads 1282046 Variation of Refractive Errors among Right and Left Eyes in Jos, Plateau State, Nigeria
Authors: F. B. Masok, S. S Songdeg, R. R. Dawam
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Vision is an important process for learning and communication as man depends greatly on vision to sense his environment. Prevalence and variation of refractive errors conducted between December 2010 and May 2011 in Jos, revealed that 735 (77.50%) out 950 subjects examined for refractive error had various refractive errors. Myopia was observed in 373 (49.79%) of the subjects, the error in the right eyes was 263 (55.60%) while the error in the left was 210(44.39%). The mean myopic error was found to be -1.54± 3.32. Hyperopia was observed in 385 (40.53%) of the sampled population comprising 203(52.73%) of the right eyes and 182(47.27%). The mean hyperopic error was found to be +1.74± 3.13. Astigmatism accounted for 359 (38.84%) of the subjects, out of which 193(53.76%) were in the right eyes while 168(46.79%) were in the left eyes. Presbyopia was found in 404(42.53%) of the subjects, of this figure, 164(40.59%) were in the right eyes while 240(59.41%) were in left eyes. The number of right eyes and left eyes with refractive errors was observed in some age groups to increase with age and later had its peak within 60 – 69 age groups. This pattern of refractive errors could be attributed to exposure to various forms of light particularly the ultraviolet rays (e.g rays from television and computer screen). There was no remarkable differences between the mean Myopic error and mean Hyperopic error in the right eyes and in the left eyes which suggest the right eye and the left eye are similar.Keywords: left eye, refractive errors, right eye, variation
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