Search results for: Infiltration extraction method
14246 Detection of Paenibacillus larvae (American Foulbrood Disease) by the PCR and Culture in the Remains of the Hive Collected at the Bottom of the Colony
Authors: N. Adjlane, N. Haddad
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The American foulbrood is one of the most serious diseases that may affect brood of larvae and pupae stages. The causative organism is a gram positive bacterium Paaenibacillus larvae. American foulbrood infected apiaries suffer from severe economic losses, resulting from significant decreases in honeybee populations and honey production. The aim of this study was to detect Paenibacillus larvae in the remains collected at the bottom of the hive from the suspected hives by direct PCR and culture growth. A total of 56 suspected beehive wax debris samples collected in 40 different apiaries located in the central region of Algeria. MYPGP the culture medium is used during all the identifications of the bacterium. After positive results on samples, biochemical confirmation tests (test of catalase, presence hydrolysis of casein) and microscopic (gram stain) are used in order to verify the accuracy of the initial results. The QIAamp DNA Mini Kit is used to identify the DNA of Paaenibacillus larvae. Paaenibacillus larvae were identified in 14 samples out of 16 by the PCR. A suspected culture-negative sample was found positive through evaluation with PCR. This research is for the bacterium Paaenibacillus larvae in the debris of the colony is an effective method for diagnosis of the pathology of American foulbrood.Keywords: Paenibacillus larvae, honeybee, PCR, microbiological method
Procedia PDF Downloads 40414245 Investigating a Modern Accident Analysis Model for Textile Building Fires through Numerical Reconstruction
Authors: Mohsin Ali Shaikh, Weiguo Song, Rehmat Karim, Muhammad Kashan Surahio, Muhammad Usman Shahid
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Fire investigations face challenges due to the complexity of fire development, and real-world accidents lack repeatability, making it difficult to apply standardized approaches. The unpredictable nature of fires and the unique conditions of each incident contribute to the complexity, requiring innovative methods and tools for effective analysis and reconstruction. This study proposes to provide the modern accident analysis model through numerical reconstruction for fire investigation in textile buildings. This method employs computer simulation to enhance the overall effectiveness of textile-building investigations. The materials and evidence collected from past incidents reconstruct fire occurrences, progressions, and catastrophic processes. The approach is demonstrated through a case study involving a tragic textile factory fire in Karachi, Pakistan, which claimed 257 lives. The reconstruction method proves invaluable for determining fire origins, assessing losses, establishing accountability, and, significantly, providing preventive insights for complex fire incidents.Keywords: fire investigation, numerical simulation, fire safety, fire incident, textile building
Procedia PDF Downloads 6114244 Reclamation of Molding Sand: A Chemical Approach to Recycle Waste Foundry Sand
Authors: Mohd Moiz Khan, S. M. Mahajani, G. N. Jadhav
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Waste foundry sand (total clay content 15%) contains toxic heavy metals and particulate matter which make dumping of waste sand an environmental and health hazard. Disposal of waste foundry sand (WFS) remains one of the substantial challenges faced by Indian foundries nowadays. To cope up with this issue, the chemical method was used to reclaim WFS. A stirrer tank reactor was used for chemical reclamation. Experiments were performed to reduce the total clay content from 15% to as low as 0.9% in chemical reclamation. This method, although found to be effective for WFS reclamation, it may face a challenge due to the possibly high operating cost. Reclaimed sand was found to be satisfactory in terms of sand qualities such as total clay (0.9%), active clay (0.3%), acid demand value (ADV) (2.6%), loss on igniting (LOI) (3 %), grain fineness number (GFN) (56), and compressive strength (60 kPa). The experimental data generated on chemical reactor under different conditions is further used to optimize the design and operating parameters (rotation speed, sand to acidic solution ratio, acid concentration, temperature and time) for the best performance. The use of reclaimed sand within the foundry would improve the economics and efficiency of the process and reduce environmental concerns.Keywords: chemical reclamation, clay content, environmental concerns, recycle, waste foundry sand
Procedia PDF Downloads 14114243 Analysis of Vibratory Signals Based on Local Mean Decomposition (LMD) for Rolling Bearing Fault Diagnosis
Authors: Toufik Bensana, Medkour Mihoub, Slimane Mekhilef
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The use of vibration analysis has been established as the most common and reliable method of analysis in the field of condition monitoring and diagnostics of rotating machinery. Rolling bearings cover a broad range of rotary machines and plays a crucial role in the modern manufacturing industry. Unfortunately, the vibration signals collected from a faulty bearing are generally nonstationary, nonlinear and with strong noise interference, so it is essential to obtain the fault features correctly. In this paper, a novel numerical analysis method based on local mean decomposition (LMD) is proposed. LMD decompose the signal into a series of product functions (PFs), each of which is the product of an envelope signal and a purely frequency modulated FM signal. The envelope of a PF is the instantaneous amplitude (IA), and the derivative of the unwrapped phase of a purely flat frequency demodulated (FM) signal is the IF. After that, the fault characteristic frequency of the roller bearing can be extracted by performing spectrum analysis to the instantaneous amplitude of PF component containing dominant fault information. The results show the effectiveness of the proposed technique in fault detection and diagnosis of rolling element bearing.Keywords: fault diagnosis, rolling element bearing, local mean decomposition, condition monitoring
Procedia PDF Downloads 38214242 Perceptual Image Coding by Exploiting Internal Generative Mechanism
Authors: Kuo-Cheng Liu
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In the perceptual image coding, the objective is to shape the coding distortion such that the amplitude of distortion does not exceed the error visibility threshold, or to remove perceptually redundant signals from the image. While most researches focus on color image coding, the perceptual-based quantizer developed for luminance signals are always directly applied to chrominance signals such that the color image compression methods are inefficient. In this paper, the internal generative mechanism is integrated into the design of a color image compression method. The internal generative mechanism working model based on the structure-based spatial masking is used to assess the subjective distortion visibility thresholds that are visually consistent to human eyes better. The estimation method of structure-based distortion visibility thresholds for color components is further presented in a locally adaptive way to design quantization process in the wavelet color image compression scheme. Since the lowest subband coefficient matrix of images in the wavelet domain preserves the local property of images in the spatial domain, the error visibility threshold inherent in each coefficient of the lowest subband for each color component is estimated by using the proposed spatial error visibility threshold assessment. The threshold inherent in each coefficient of other subbands for each color component is then estimated in a local adaptive fashion based on the distortion energy allocation. By considering that the error visibility thresholds are estimated using predicting and reconstructed signals of the color image, the coding scheme incorporated with locally adaptive perceptual color quantizer does not require side information. Experimental results show that the entropies of three color components obtained by using proposed IGM-based color image compression scheme are lower than that obtained by using the existing color image compression method at perceptually lossless visual quality.Keywords: internal generative mechanism, structure-based spatial masking, visibility threshold, wavelet domain
Procedia PDF Downloads 24414241 Studying on Pile Seismic Operation with Numerical Method by Using FLAC 3D Software
Authors: Hossein Motaghedi, Kaveh Arkani, Siavash Salamatpoor
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Usually the piles are important tools for safety and economical design of high and heavy structures. For this aim the response of single pile under dynamic load is so effective. Also, the agents which have influence on single pile response are properties of pile geometrical, soil and subjected loads. In this study the finite difference numerical method and by using FLAC 3D software is used for evaluation of single pile behavior under peak ground acceleration (PGA) of El Centro earthquake record in California (1940). The results of this models compared by experimental results of other researchers and it will be seen that the results of this models are approximately coincide by experimental data's. For example the maximum moment and displacement in top of the pile is corresponding to the other experimental results of pervious researchers. Furthermore, in this paper is tried to evaluate the effective properties between soil and pile. The results is shown that by increasing the pile diagonal, the pile top displacement will be decreased. As well as, by increasing the length of pile, the top displacement will be increased. Also, by increasing the stiffness ratio of pile to soil, the produced moment in pile body will be increased and the taller piles have more interaction by soils and have high inertia. So, these results can help directly to optimization design of pile dimensions.Keywords: pile seismic response, interaction between soil and pile, numerical analysis, FLAC 3D
Procedia PDF Downloads 38114240 Assessment of Material Type, Diameter, Orientation and Closeness of Fibers in Vulcanized Reinforced Rubbers
Authors: Ali Osman Güney, Bahattin Kanber
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In this work, the effect of material type, diameter, orientation and closeness of fibers on the general performance of reinforced vulcanized rubbers are investigated using finite element method with experimental verification. Various fiber materials such as hemp, nylon, polyester are used for different fiber diameters, orientations and closeness. 3D finite element models are developed by considering bonded contact elements between fiber and rubber sheet interfaces. The fibers are assumed as linear elastic, while vulcanized rubber is considered as hyper-elastic. After an experimental verification of finite element results, the developed models are analyzed under prescribed displacement that causes tension. The normal stresses in fibers and shear stresses between fibers and rubber sheet are investigated in all models. Large deformation of reinforced rubber sheet also represented with various fiber conditions under incremental loading. A general assessment is achieved about best fiber properties of reinforced rubber sheets for tension-load conditions.Keywords: reinforced vulcanized rubbers, fiber properties, out of plane loading, finite element method
Procedia PDF Downloads 34014239 Correlation between Total Polyphenol Content and Antimicrobial Activity of Opuntia ficus indica Extracts against Periodontopathogenic Bacteria
Authors: N. Chikhi-Chorfi, L. Arbia, S. Zenia, H.Lounici
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Opuntia ficus-indica belongs to the Cactaceae family. The cactus is mainly cultivated for its fruit (prickly pear) that, eaten after pealing, is sweet and juicy, and rich in nutritional compounds, such as ascorbic acid and polyphenols. Different parts of O. ficus-indica are used in the traditional medicine of several countries: the cladodes are utilized to reduce serum cholesterol level and blood pressure, for treatment of ulcers, rheumatic pain, wounds, fatigue, capillary fragility, and liver conditions. This original study, investigate the effect of polyphenols of O. ficus indica (cactus) cladodes against periodontal bacteria collected from patients with periodontitis. The quantitative analysis of total polyphenols (TPP) was determined with Follin-Ciocalteu method. Different concentrations of extracts of O. ficus indica were tested by the disk method on two bacterial strains: Porphyromonas gingivalis and Prevotella intermedia responsible for periodontal disease. The results showed a good correlation between the concentration of total polyphenols and the antibacterial activity of the extracts of Opuntia ficus indica against P. gingivalis and P. intermedia with R² = 0.94 and R² = 0.90 respectively. This observation suggests that these extracts could be used in the treatment and prevention of periodontitis.Keywords: periodontal disease, P. gingivalis, P. intermedia, polyphenols, Opuntia ficus indica
Procedia PDF Downloads 13914238 Genetic Variation among the Wild and Hatchery Raised Populations of Labeo rohita Revealed by RAPD Markers
Authors: Fayyaz Rasool, Shakeela Parveen
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The studies on genetic diversity of Labeo rohita by using molecular markers were carried out to investigate the genetic structure by RAPAD marker and the levels of polymorphism and similarity amongst the different groups of five populations of wild and farmed types. The samples were collected from different five locations as representatives of wild and hatchery raised populations. RAPAD data for Jaccard’s coefficient by following the un-weighted Pair Group Method with Arithmetic Mean (UPGMA) for Hierarchical Clustering of the similar groups on the basis of similarity amongst the genotypes and the dendrogram generated divided the randomly selected individuals of the five populations into three classes/clusters. The variance decomposition for the optimal classification values remained as 52.11% for within class variation, while 47.89% for the between class differences. The Principal Component Analysis (PCA) for grouping of the different genotypes from the different environmental conditions was done by Spearman Varimax rotation method for bi-plot generation of the co-occurrence of the same genotypes with similar genetic properties and specificity of different primers indicated clearly that the increase in the number of factors or components was correlated with the decrease in eigenvalues. The Kaiser Criterion based upon the eigenvalues greater than one, first two main factors accounted for 58.177% of cumulative variability.Keywords: variation, clustering, PCA, wild, hatchery, RAPAD, Labeo rohita
Procedia PDF Downloads 43814237 Production of Pre-Reduction of Iron Ore Nuggets with Lesser Sulphur Intake by Devolatisation of Boiler Grade Coal
Authors: Chanchal Biswas, Anrin Bhattacharyya, Gopes Chandra Das, Mahua Ghosh Chaudhuri, Rajib Dey
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Boiler coals with low fixed carbon and higher ash content have always challenged the metallurgists to develop a suitable method for their utilization. In the present study, an attempt is made to establish an energy effective method for the reduction of iron ore fines in the form of nuggets by using ‘Syngas’. By devolatisation (expulsion of volatile matter by applying heat) of boiler coal, gaseous product (enriched with reducing agents like CO, CO2, H2, and CH4 gases) is generated. Iron ore nuggets are reduced by this syngas. For that reason, there is no direct contact between iron ore nuggets and coal ash. It helps to control the minimization of the sulphur intake of the reduced nuggets. A laboratory scale devolatisation furnace designed with reduction facility is evaluated after in-depth studies and exhaustive experimentations including thermo-gravimetric (TG-DTA) analysis to find out the volatile fraction present in boiler grade coal, gas chromatography (GC) to find out syngas composition in different temperature and furnace temperature gradient measurements to minimize the furnace cost by applying one heating coil. The nuggets are reduced in the devolatisation furnace at three different temperatures and three different times. The pre-reduced nuggets are subjected to analytical weight loss calculations to evaluate the extent of reduction. The phase and surface morphology analysis of pre-reduced samples are characterized using X-ray diffractometry (XRD), energy dispersive x-ray spectrometry (EDX), scanning electron microscopy (SEM), carbon sulphur analyzer and chemical analysis method. Degree of metallization of the reduced nuggets is 78.9% by using boiler grade coal. The pre-reduced nuggets with lesser sulphur content could be used in the blast furnace as raw materials or coolant which would reduce the high quality of coke rate of the furnace due to its pre-reduced character. These can be used in Basic Oxygen Furnace (BOF) as coolant also.Keywords: alternative ironmaking, coal gasification, extent of reduction, nugget making, syngas based DRI, solid state reduction
Procedia PDF Downloads 25414236 Ambiguity Resolution for Ground-based Pulse Doppler Radars Using Multiple Medium Pulse Repetition Frequency
Authors: Khue Nguyen Dinh, Loi Nguyen Van, Thanh Nguyen Nhu
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In this paper, we propose an adaptive method to resolve ambiguities and a ghost target removal process to extract targets detected by a ground-based pulse-Doppler radar using medium pulse repetition frequency (PRF) waveforms. The ambiguity resolution method is an adaptive implementation of the coincidence algorithm, which is implemented on a two-dimensional (2D) range-velocity matrix to resolve range and velocity ambiguities simultaneously, with a proposed clustering filter to enhance the anti-error ability of the system. Here we consider the scenario of multiple target environments. The ghost target removal process, which is based on the power after Doppler processing, is proposed to mitigate ghosting detections to enhance the performance of ground-based radars using a short PRF schedule in multiple target environments. Simulation results on a ground-based pulsed Doppler radar model will be presented to show the effectiveness of the proposed approach.Keywords: ambiguity resolution, coincidence algorithm, medium PRF, ghosting removal
Procedia PDF Downloads 14414235 Seismic Behavior of Suction Caisson Foundations
Authors: Mohsen Saleh Asheghabadi, Alireza Jafari Jebeli
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Increasing population growth requires more sustainable development of energy. This non-contaminated energy has an inexhaustible energy source. One of the vital parameters in such structures is the choice of foundation type. Suction caissons are now used extensively worldwide for offshore wind turbine. Considering the presence of a number of offshore wind farms in earthquake areas, the study of the seismic behavior of suction caisson is necessary for better design. In this paper, the results obtained from three suction caisson models with different diameter (D) and skirt length (L) in saturated sand were compared with centrifuge test results. All models are analyzed using 3D finite element (FE) method taking account of elasto-plastic Mohr–Coulomb constitutive model for soil which is available in the ABAQUS library. The earthquake load applied to the base of models with a maximum acceleration of 0.65g. The results showed that numerical method is in relative good agreement with centrifuge results. The settlement and rotation of foundation decrease by increasing the skirt length and foundation diameter. The sand soil outside the caisson is prone to liquefaction due to its low confinement.Keywords: liquefaction, suction caisson foundation, offshore wind turbine, numerical analysis, seismic behavior
Procedia PDF Downloads 11714234 Reliability and Probability Weighted Moment Estimation for Three Parameter Mukherjee-Islam Failure Model
Authors: Ariful Islam, Showkat Ahmad Lone
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The Mukherjee-Islam Model is commonly used as a simple life time distribution to assess system reliability. The model exhibits a better fit for failure information and provides more appropriate information about hazard rate and other reliability measures as shown by various authors. It is possible to introduce a location parameter at a time (i.e., a time before which failure cannot occur) which makes it a more useful failure distribution than the existing ones. Even after shifting the location of the distribution, it represents a decreasing, constant and increasing failure rate. It has been shown to represent the appropriate lower tail of the distribution of random variables having fixed lower bound. This study presents the reliability computations and probability weighted moment estimation of three parameter model. A comparative analysis is carried out between three parameters finite range model and some existing bathtub shaped curve fitting models. Since probability weighted moment method is used, the results obtained can also be applied on small sample cases. Maximum likelihood estimation method is also applied in this study.Keywords: comparative analysis, maximum likelihood estimation, Mukherjee-Islam failure model, probability weighted moment estimation, reliability
Procedia PDF Downloads 26614233 Microdosimetry in Biological Cells: A Monte Carlo Method
Authors: Hamidreza Jabal Ameli, Anahita Movahedi
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Purpose: In radionuclide therapy, radioactive atoms are coupled to monoclonal antibodies (mAbs) for treating cancer tumor while limiting radiation to healthy tissues. We know that tumoral and normal tissues are not equally sensitive to radiation. In fact, biological effects such as cellular repair processes or the presence of less radiosensitive cells such as hypoxic cells should be taken account. For this reason, in this paper, we want to calculate biological effect dose (BED) inside tumoral area and healthy cells around tumors. Methods: In this study, deposited doses of a radionuclide, gold-198, inside cells lattice and surrounding healthy tissues were calculated with Monte Carlo method. The elemental compositions and density of malignant and healthy tissues were obtained from ICRU Report 44. For reaching to real condition of oxygen effects, the necrosis and hypoxia area inside tumors has been assessed. Results: With regard to linear-quadratic expression which was defined in Monte Carlo, results showed that a large amount of BED is deposited in the well-oxygenated part of the hypoxia area compared to necrosis area. Moreover, there is a significant difference between the curves of absorbed dose with BED and without BED.Keywords: biological dose, monte carlo, hypoxia, radionuclide therapy
Procedia PDF Downloads 47814232 Multiobjective Optimization of a Pharmaceutical Formulation Using Regression Method
Authors: J. Satya Eswari, Ch. Venkateswarlu
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The formulation of a commercial pharmaceutical product involves several composition factors and response characteristics. When the formulation requires to satisfy multiple response characteristics which are conflicting, an optimal solution requires the need for an efficient multiobjective optimization technique. In this work, a regression is combined with a non-dominated sorting differential evolution (NSDE) involving Naïve & Slow and ε constraint techniques to derive different multiobjective optimization strategies, which are then evaluated by means of a trapidil pharmaceutical formulation. The analysis of the results show the effectiveness of the strategy that combines the regression model and NSDE with the integration of both Naïve & Slow and ε constraint techniques for Pareto optimization of trapidil formulation. With this strategy, the optimal formulation at pH=6.8 is obtained with the decision variables of micro crystalline cellulose, hydroxypropyl methylcellulose and compression pressure. The corresponding response characteristics of rate constant and release order are also noted down. The comparison of these results with the experimental data and with those of other multiple regression model based multiobjective evolutionary optimization strategies signify the better performance for optimal trapidil formulation.Keywords: pharmaceutical formulation, multiple regression model, response surface method, radial basis function network, differential evolution, multiobjective optimization
Procedia PDF Downloads 40014231 Preparation and Fabrication of Lithium Disilicate Glass Ceramic as Dental Crowns via Hot Pressing Method
Authors: A. Srion, W. Thepsuwan, N. Monmaturapoj
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Two Lithium disilicate (LD) glass ceramics based on SiO2-Li2O-K2O-Al2O3 system were prepared through glass melting method and then fabricated into dental crowns via hot pressing at 850˚C and 900˚C in order to study the effect of the pressing temperatures on theirs phase formation and microstructure. The factor such as heat treatment temperature (as-cast glass, 600˚C and 700˚C) of the glass ceramics used to press was also investigated the effect of an initial microstructure before pressing. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to determine phase formation and microstructure of the samples, respectively. X-ray diffraction result shows that the main crystalline structure was Li2Si2O5 by having Li3PO4, Li0.6Al0.6Si2O6, Li2SiO3, Ca5 (PO4)3F, SiO2 as minor phases. Glass compositions with different heat treatment temperatures exhibited a difference phase formation but have less effect during pressing. Scanning electron microscopy analysis showed microstructure of lath-like of Li2Si2O5 in all glasses. With increasing the initial heat treatment temperature, the longer the lath-like crystals of lithium disilicate were increased especially when using glass heat treatment at 700˚C followed by pressing at 900˚C. This could be suggested that LD1 heat treatment at 700˚C which pressing at 900˚C presented the best formation by hot pressing and compiled microstructure.Keywords: lithium disilicate, hot pressing, dental crown, microstructure
Procedia PDF Downloads 31814230 Prediction of Concrete Hydration Behavior and Cracking Tendency Based on Electrical Resistivity Measurement, Cracking Test and ANSYS Simulation
Authors: Samaila Muazu Bawa
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Hydration process, crack potential and setting time of concrete grade C30, C40 and C50 were separately monitored using non-contact electrical resistivity apparatus, a plastic ring mould and penetration resistance method respectively. The results show highest resistivity of C30 at the beginning until reaching the acceleration point when C50 accelerated and overtaken the others, and this period corresponds to its final setting time range, from resistivity derivative curve, hydration process can be divided into dissolution, induction, acceleration and deceleration periods, restrained shrinkage crack and setting time tests demonstrated the earliest cracking and setting time of C50, therefore, this method conveniently and rapidly determines the concrete’s crack potential. The highest inflection time (ti), the final setting time (tf) were obtained and used with crack time in coming up with mathematical models for the prediction of concrete’s cracking age for the range being considered. Finally, ANSYS numerical simulations supports the experimental findings in terms of the earliest crack age of C50 and the crack location that, highest stress concentration is always beneath the artificially introduced expansion joint of C50.Keywords: concrete hydration, electrical resistivity, restrained shrinkage crack, ANSYS simulation
Procedia PDF Downloads 23214229 Stress among Mothers of Children with Cerebral Palsy
Authors: Priyanka Tiwari, Uma Devi Ranjit, Ritesh Thapa
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Background and Significance: Cerebral Palsy (CP) influences not only the child's everyday functioning but also the functioning of whole family. Application of study findings can be used in clinical or community setting to screen the parents of children with cerebral palsy in order to identify the compromised domain of stress which in turn will help to improve the interaction between parent and child with disability and thus ultimately affect the progress that a child makes in his or her therapeutic or educational programs. Objective: The objective of the study was to assess the level of stress in mothers of children with CP by adopting mixed method design. Methodology: Cross-sectional descriptive design was adopted in the quantitative design where Parental Stress Scale (PSS) was utilized to collect data from a convenient sample of 40 mothers of children with CP who were under regular follow-up by home visitor of Self-help Group for Cerebral Palsy while embedded qualitative design was used to explore the stress of mothers of CP affected children. From the parent population of quantitative sample 4 mothers were chosen for in-depth exploration, regarding their stress by means of case study method. Descriptive statistics like frequency, percentage, mean, median, standard deviation, correlation and inferential statistics like Mann-Whitney U test and Kruskal-Wallis H test were used to describe and assess relationship between variables. Findings: The mean stress experienced by mothers of children with cerebral palsy was 53.62±9.53 with 15% percent of the mothers experiencing severe stress. There was significant association between age group of mother and total stress score and negative themes of stress. Similarly, signification association was found between educational status of the mother and positive themes of stress which was convergent with the qualitative finding as well, where literate mothers had more positive view of their child's disability which could be attributed to their educational level as education provides us with a broad perspective to look at a situation. Conclusions: Still one-sixth of the mothers experienced severe stress so if we want to ensure the well-being of the children affected by cerebral palsy, then parents caring for them need to be looked after as well.Keywords: stress, cerebral palsy, mothers, mixed method
Procedia PDF Downloads 25214228 Modeling Anisotropic Damage Algorithms of Metallic Structures
Authors: Bahar Ayhan
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The present paper is concerned with the numerical modeling of the inelastic behavior of the anisotropically damaged ductile materials, which are based on a generalized macroscopic theory within the framework of continuum damage mechanics. Kinematic decomposition of the strain rates into elastic, plastic and damage parts is basis for accomplishing the structure of continuum theory. The evolution of the damage strain rate tensor is detailed with the consideration of anisotropic effects. Helmholtz free energy functions are constructed separately for the elastic and inelastic behaviors in order to be able to address the plastic and damage process. Additionally, the constitutive structure, which is based on the standard dissipative material approach, is elaborated with stress tensor, a yield criterion for plasticity and a fracture criterion for damage besides the potential functions of each inelastic phenomenon. The finite element method is used to approximate the linearized variational problem. Stress and strain outcomes are solved by using the numerical integration algorithm based on operator split methodology with a plastic and damage (multiplicator) variable separately. Numerical simulations are proposed in order to demonstrate the efficiency of the formulation by comparing the examples in the literature.Keywords: anisotropic damage, finite element method, plasticity, coupling
Procedia PDF Downloads 19614227 Automatic Detection of Sugarcane Diseases: A Computer Vision-Based Approach
Authors: Himanshu Sharma, Karthik Kumar, Harish Kumar
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The major problem in crop cultivation is the occurrence of multiple crop diseases. During the growth stage, timely identification of crop diseases is paramount to ensure the high yield of crops, lower production costs, and minimize pesticide usage. In most cases, crop diseases produce observable characteristics and symptoms. The Surveyors usually diagnose crop diseases when they walk through the fields. However, surveyor inspections tend to be biased and error-prone due to the nature of the monotonous task and the subjectivity of individuals. In addition, visual inspection of each leaf or plant is costly, time-consuming, and labour-intensive. Furthermore, the plant pathologists and experts who can often identify the disease within the plant according to their symptoms in early stages are not readily available in remote regions. Therefore, this study specifically addressed early detection of leaf scald, red rot, and eyespot types of diseases within sugarcane plants. The study proposes a computer vision-based approach using a convolutional neural network (CNN) for automatic identification of crop diseases. To facilitate this, firstly, images of sugarcane diseases were taken from google without modifying the scene, background, or controlling the illumination to build the training dataset. Then, the testing dataset was developed based on the real-time collected images from the sugarcane field from India. Then, the image dataset is pre-processed for feature extraction and selection. Finally, the CNN-based Visual Geometry Group (VGG) model was deployed on the training and testing dataset to classify the images into diseased and healthy sugarcane plants and measure the model's performance using various parameters, i.e., accuracy, sensitivity, specificity, and F1-score. The promising result of the proposed model lays the groundwork for the automatic early detection of sugarcane disease. The proposed research directly sustains an increase in crop yield.Keywords: automatic classification, computer vision, convolutional neural network, image processing, sugarcane disease, visual geometry group
Procedia PDF Downloads 11014226 Synthesis and Characterization of Functionalized Carbon Nanorods/Polystyrene Nanocomposites
Authors: M. A. Karakassides, M. Baikousi, A. Kouloumpis, D. Gournis
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Nanocomposites of Carbon Nanorods (CNRs) with Polystyrene (PS), have been synthesized successfully by means of in situ polymerization process and characterized. Firstly, carbon nanorods with graphitic structure were prepared by the standard synthetic procedure of CMK-3 using MCM-41 as template, instead of SBA-15, and sucrose as carbon source. In order to create an organophilic surface on CNRs, two parts of modification were realized: surface chemical oxidation (CNRs-ox) according to the Staudenmaier’s method and the attachment of octadecylamine molecules on the functional groups of CNRs-ox (CNRs-ODA The nanocomposite materials of polystyrene with CNRs-ODA, were prepared by a solution-precipitation method at three nanoadditive to polymer loadings (1, 3 and 5 wt. %). The as derived nanocomposites were studied with a combination of characterization and analytical techniques. Especially, Fourier-transform infrared (FT-IR) and Raman spectroscopies were used for the chemical and structural characterization of the pristine materials and the derived nanocomposites while the morphology of nanocomposites and the dispersion of the carbon nanorods were analyzed by atomic force and scanning electron microscopy techniques. Tensile testing and thermogravimetric analysis (TGA) along with differential scanning calorimetry (DSC) were also used to examine the mechanical properties and thermal stability -glass transition temperature of PS after the incorporation of CNRs-ODA nanorods. The results showed that the thermal and mechanical properties of the PS/ CNRs-ODA nanocomposites gradually improved with increasing of CNRs-ODA loading.Keywords: nanocomposites, polystyrene, carbon, nanorods
Procedia PDF Downloads 34314225 Energy Loss Reduction in Oil Refineries through Flare Gas Recovery Approaches
Authors: Majid Amidpour, Parisa Karimi, Marzieh Joda
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For the last few years, release of burned undesirable by-products has become a challenging issue in oil industries. Flaring, as one of the main sources of air contamination, involves detrimental and long-lasting effects on human health and is considered a substantial reason for energy losses worldwide. This research involves studying the implications of two main flare gas recovery methods at three oil refineries, all in Iran as the case I, case II, and case III in which the production capacities are increasing respectively. In the proposed methods, flare gases are converted into more valuable products, before combustion by the flare networks. The first approach involves collecting, compressing and converting the flare gas to smokeless fuel which can be used in the fuel gas system of the refineries. The other scenario includes utilizing the flare gas as a feed into liquefied petroleum gas (LPG) production unit already established in the refineries. The processes of these scenarios are simulated, and the capital investment is calculated for each procedure. The cumulative profits of the scenarios are evaluated using Net Present Value method. Furthermore, the sensitivity analysis based on total propane and butane mole fraction is carried out to make a rational comparison for LPG production approach, and the results are illustrated for different mole fractions of propane and butane. As the mole fraction of propane and butane contained in LPG differs in summer and winter seasons, the results corresponding to LPG scenario are demonstrated for each season. The results of the simulations show that cumulative profit in fuel gas production scenario and LPG production rate increase with the capacity of the refineries. Moreover, the investment return time in LPG production method experiences a decline, followed by a rising trend with an increase in C3 and C4 content. The minimum value of time return occurs at propane and butane sum concentration values of 0.7, 0.6, and 0.7 in case I, II, and III, respectively. Based on comparison of the time of investment return and cumulative profit, fuel gas production is the superior scenario for three case studies.Keywords: flare gas reduction, liquefied petroleum gas, fuel gas, net present value method, sensitivity analysis
Procedia PDF Downloads 15014224 Genre Analysis of Postgraduate Theses and Dissertations: Case of Statement of the Problem
Authors: H. Mashhady, H. A. Manzoori, M. Doosti, M. Fatollahi
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This study reports a descriptive research in the form of a genre analysis of postgraduates' theses and dissertations at three Iranian universities, including Ferdowsi, Tehran, and Tarbiat Moddares universities. The researchers sought to depict the generic structure of “statement of the problem” section of PhD dissertations and MA theses. Moreover, researchers desired to find any probable variety based on the year the dissertations belonged, to see weather genre-consciousness developed among Iranian postgraduates. To obtain data, “statement of the problem” section of 90 Ph.D. dissertations and MA theses from 2001 to 2013 in Teaching English as a Foreign Language (TEFL) at above-mentioned universities was selected. Frequency counts was employed for the quantitative method of data analysis, while genre analysis was used as the qualitative method. Inter-rater reliability was found to be about 0.93. Results revealed that students in different degrees at each of these universities used various generic structures for writing “statement of the problem”. Moreover, comparison of different time periods (2001-2006, and 2007-2013) revealed that postgraduates in the second time period, regardless of their degree and university, employed more similar generic structures which can be optimistically attributed to a general raise in genre awareness.Keywords: genre, genre analysis, Ph.D. and MA dissertations, statement of the problem, generic structure
Procedia PDF Downloads 66514223 Numerical Simulation of Natural Gas Dispersion from Low Pressure Pipelines
Authors: Omid Adibi, Nategheh Najafpour, Bijan Farhanieh, Hossein Afshin
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Gas release from the pipelines is one of the main factors in the gas industry accidents. Released gas ejects from the pipeline as a free jet and in the growth process, the fuel gets mixed with the ambient air. Accordingly, an accidental spark will release the chemical energy of the mixture with an explosion. Gas explosion damages the equipment and endangers the life of staffs. So due to importance of safety in gas industries, prevision of accident can reduce the number of the casualties. In this paper, natural gas leakages from the low pressure pipelines are studied in two steps: 1) the simulation of mixing process and identification of flammable zones and 2) the simulation of wind effects on the mixing process. The numerical simulations were performed by using the finite volume method and the pressure-based algorithm. Also, for the grid generation the structured method was used. The results show that, in just 6.4 s after accident, released natural gas could penetrate to 40 m in vertical and 20 m in horizontal direction. Moreover, the results show that the wind speed is a key factor in dispersion process. In fact, the wind transports the flammable zones into the downstream. Hence, to improve the safety of the people and human property, it is preferable to construct gas facilities and buildings in the opposite side of prevailing wind direction.Keywords: flammable zones, gas pipelines, numerical simulation, wind effects
Procedia PDF Downloads 15914222 Mobile Phones in Saudi Arabian EFL Classrooms
Authors: Srinivasa Rao Idapalapati, Manssour Habbash
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As mobile connectedness continues to sweep across the landscape, the value of deploying mobile technology to the service of learning and teaching appears to be both self-evident and unavoidable. To this end, this study explores the reasons for the reluctance of teachers in Saudi Arabia to use mobiles in EFL (English as a Foreign Language) classes for teaching and learning purposes. The main objective of this study is a qualitative analysis of the responses of the views of the teachers at a university in Saudi Arabia about the use of mobile phones in classrooms for educational purposes. Driven by the hypothesis that the teachers in Saudi Arabian universities aren’t prepared well enough to use mobile phones in classrooms for educational purposes, this study examines the data obtained through a questionnaire provided to about hundred teachers working at a university in Saudi Arabia through convenient sampling method. The responses are analyzed by qualitative interpretive method and found that teachers and the students are in confusion whether to use mobiles, and need some training sessions on the use of mobile phones in classrooms for educational purposes. The outcome of the analysis is discussed in light of the concerns bases adoption model and the inferences are provided in a descriptive mode.Keywords: mobile assisted language learning, technology adoption, classroom instruction, concerns based adoption model
Procedia PDF Downloads 36014221 Evaluating the Rationality of Airport Design from the Perspective of Passenger Experience: An Example of Terminal 3 of Beijing Capital International Airport
Authors: Yan Li, Yujiang Gao
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Passengers are the main users of the airport. Whether the travel experience of passengers in the airport is comfortable or not is an important indicator for evaluating the reasonableness of airport design. Taking the Terminal 3 of Beijing Capital International Airport as an example, this paper analyzes the airport’s solution to the problem of passengers’ inconvenience caused by lost directions, excessive congestion, and excessively long streamlines during passenger use. First of all, by using the method of analyzing the design of architectural function streamlines, the design of interior spaces of buildings, and the interrelationship between interior design and passenger experience, it was first concluded that the airport is capable of performing the two major problems of easy disorientation and excessive congestion. Later, by using the method of analyzing architectural function streamlines and collecting passenger experience evaluations, it was concluded that the airport could not solve the inconvenience caused by excessively long streamlines to passengers. Finally came to the conclusion that the airport design meets the demand in terms of the overall design of the passenger experience, but the boarding line is still relatively long and some fly in the ointment.Keywords: passengers’ experience, terminal 3 of Beijing capital international airport, lost directions, excessive congestion, excessively long streamlines
Procedia PDF Downloads 19214220 Evaluation of Iron Application Method to Remediate Coastal Marine Sediment
Authors: Ahmad Seiar Yasser
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Sediment is an important habitat for organisms and act as a store house for nutrients in aquatic ecosystems. Hydrogen sulfide is produced by microorganisms in the water columns and sediments, which is highly toxic and fatal to benthic organisms. However, the irons have the capacity to regulate the formation of sulfide by poising the redox sequence and to form insoluble iron sulfide and pyrite compounds. Therefore, we conducted two experiments aimed to evaluate the remediation efficiency of iron application to organically enrich and improve sediments environment. Experiments carried out in the laboratory using intact sediment cores taken from Mikawa Bay, Japan at every month from June to September 2017 and October 2018. In Experiment 1, after cores were collected, the iron powder or iron hydroxide were applied to the surface sediment with 5 g/ m2 or 5.6 g/ m2, respectively. In Experiment 2, we experimentally investigated the removal of hydrogen sulfide using (2mm or less and 2 to 5mm) of the steelmaking slag. Experiments are conducted both in the laboratory with the same boundary conditions. The overlying water were replaced with deoxygenated filtered seawater, and cores were sealed a top cap to keep anoxic condition with a stirrer to circulate the overlying water gently. The incubation experiments have been set in three treatments included the control, and each treatment replicated and were conducted with the same temperature of the in-situ conditions. Water samples were collected to measure the dissolved sulfide concentrations in the overlying water at appropriate time intervals by the methylene blue method. Sediment quality was also analyzed after the completion of the experiment. After the 21 days incubation, experimental results using iron powder and ferric hydroxide revealed that application of these iron containing materials significantly reduced sulfide release flux from the sediment into the overlying water. The average dissolved sulfides concentration in the overlying water of the treatment group was significantly decrease (p = .0001). While no significant difference was observed between the control group after 21 day incubation. Therefore, the application of iron to the sediment is a promising method to remediate contaminated sediments in a eutrophic water body, although ferric hydroxide has better hydrogen sulfide removal effects. Experiments using the steelmaking slag also clarified the fact that capping with (2mm or less and 2 to 5mm) of slag steelmaking is an effective technique for remediation of bottom sediments enriched organic containing hydrogen sulfide because it leads to the induction of chemical reaction between Fe and sulfides occur in sediments which did not occur in conditions naturally. Although (2mm or less) of slag steelmaking has better hydrogen sulfide removal effects. Because of economic reasons, the application of steelmaking slag to the sediment is a promising method to remediate contaminated sediments in the eutrophic water body.Keywords: sedimentary, H2S, iron, iron hydroxide
Procedia PDF Downloads 15714219 Vehicle Risk Evaluation in Low Speed Accidents: Consequences for Relevant Test Scenarios
Authors: Philip Feig, Klaus Gschwendtner, Julian Schatz, Frank Diermeyer
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Projects of accident research analysis are mostly focused on accidents involving personal damage. Property damage only has a high frequency of occurrence combined with high economic impact. This paper describes main influencing parameters for the extent of damage and presents a repair cost model. For a prospective evaluation method of the monetary effect of advanced driver assistance systems (ADAS), it is necessary to be aware of and quantify all influencing parameters. Furthermore, this method allows the evaluation of vehicle concepts in combination with an ADAS at an early point in time of the product development process. In combination with a property damage database and the introduced repair cost model relevant test scenarios for specific vehicle configurations and their individual property damage risk may be determined. Currently, equipment rates of ADAS are low and a purchase incentive for customers would be beneficial. The next ADAS generation will prevent property damage to a large extent or at least reduce damage severity. Both effects may be a purchasing incentive for the customer and furthermore contribute to increased traffic safety.Keywords: accident research, accident scenarios, ADAS, effectiveness, property damage analysis
Procedia PDF Downloads 33614218 Typification and Determination of Antibiotic Susceptibility Profiles with E Test Methods of Anaerobic Gram Negative Bacilli Isolated from Various Clinical Specimen
Authors: Cengiz Demir, Recep Keşli, Gülşah Aşık
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Objective: This study was carried out with the purpose of defining by using the E test method and determining the antibiotic resistance profiles of Gram-negative anaerobic bacilli isolated from various clinical specimens obtained from patients with suspected anaerobic infections and referred to Medical Microbiology Laboratory of Afyon Kocatepe University, ANS Application and Research Hospital. Methods: Two hundred and seventy eight clinical specimens were examined for isolation of the anaerobic bacteria in Medical Microbiology Laboratory between the 1st November 2014 and 30th October 2015. Specimens were cultivated by using Scheadler agar that 5% defibrinated sheep blood added, and Scheadler broth. The isolated anaerobic Gram-negative bacilli were identified conventional methods and Vitek 2 (ANC ID Card, bioMerieux, France) cards. Antibiotic resistance rates against to penicillin G, clindamycin, cefoxitin, metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem were determined with E-test method for each isolate. Results: Of the isolated twenty-eight anaerobic gram negative bacilli fourteen were identified as the B. fragilis group, 9 were Prevotella group, and 5 were Fusobacterium group. The highest resistance rate was found against penicillin (78.5%) and resistance rates against clindamycin and cefoxitin were found as 17.8% and 21.4%, respectively. Against to the; metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem, no resistance was found. Conclusion: Since high rate resistance has been detected against to penicillin in the study penicillin should not be preferred in empirical treatment. Cefoxitin can be preferred in empirical treatment; however, carrying out the antibiotic sensitivity testing will be more proper and beneficial. No resistance was observed against carbapenem group antibiotics and metronidazole; so that reason, these antibiotics should be reserved for treatment of infectious caused by resistant strains in the future.Keywords: anaerobic gram-negative bacilli, anaerobe, antibiotics and resistance profiles, e-test method
Procedia PDF Downloads 29514217 Sensor Monitoring of the Concentrations of Different Gases Present in Synthesis of Ammonia Based on Multi-Scale Entropy and Multivariate Statistics
Authors: S. Aouabdi, M. Taibi
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The supervision of chemical processes is the subject of increased development because of the increasing demands on reliability and safety. An important aspect of the safe operation of chemical process is the earlier detection of (process faults or other special events) and the location and removal of the factors causing such events, than is possible by conventional limit and trend checks. With the aid of process models, estimation and decision methods it is possible to also monitor hundreds of variables in a single operating unit, and these variables may be recorded hundreds or thousands of times per day. In the absence of appropriate processing method, only limited information can be extracted from these data. Hence, a tool is required that can project the high-dimensional process space into a low-dimensional space amenable to direct visualization, and that can also identify key variables and important features of the data. Our contribution based on powerful techniques for development of a new monitoring method based on multi-scale entropy MSE in order to characterize the behaviour of the concentrations of different gases present in synthesis and soft sensor based on PCA is applied to estimate these variables.Keywords: ammonia synthesis, concentrations of different gases, soft sensor, multi-scale entropy, multivarite statistics
Procedia PDF Downloads 328