Search results for: analyst forecast dispersion
627 Effect of Asymmetric Amphiphilic Dicationic Ionic Liquids as Oil Spill Dispersants in Red Sea
Authors: Raghda El-Nagara, Maher I. Nessim, Carmen E. Elshafee, Renee I. Abdallah, Yasser M. Moustafa
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Three asymmetric dicationic ionic liquids (ADILs), 1-(2-(1-dodecyl-2-methyl-1H-imidazolium-3-yl)ethyl)-3-methyl pyridinium bromide (IL₁), 1-(6-(1-dodecyl-2-methyl-1H-imidazolium-3-yl)hexyl)-3-methyl pyridinium bromide (IL₂) and 1-(10-(1-dodecyl-2-methyl-1H-imidazolium-3-yl)decyl)-3-methyl pyridinium bromide (IL₃) were synthesized with yield of 83.54, 84.12 & 83.05% respectively. They were elucidated via conventional tools of analysis (elemental analysis, FT-IR, and 1H-NMR). The thermogravimetric analysis confirmed that the three ADILs possessed high thermal stability (up to 500ᵒC). Their critical micelle concentration (CMC) was investigated and exhibited values of 5.5-1*10⁻³ Mol./L. They were evaluated as oil spill dispersants were at different temperatures (10, 30 & 50ᵒC) with different concentrations (750, 1500, 2000, 3000 ppm). Data reveals that the efficiency is ranked as follows: IL₂ > IL₁ > IL₃, which showed high dispersion efficiency reached to 63% with the concentration of 1500 ppm.Keywords: ionic liquids, amphiphilic, oil spill dispersants, dicationic, efficiency test
Procedia PDF Downloads 151626 Hybrid Wavelet-Adaptive Neuro-Fuzzy Inference System Model for a Greenhouse Energy Demand Prediction
Authors: Azzedine Hamza, Chouaib Chakour, Messaoud Ramdani
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Energy demand prediction plays a crucial role in achieving next-generation power systems for agricultural greenhouses. As a result, high prediction quality is required for efficient smart grid management and therefore low-cost energy consumption. The aim of this paper is to investigate the effectiveness of a hybrid data-driven model in day-ahead energy demand prediction. The proposed model consists of Discrete Wavelet Transform (DWT), and Adaptive Neuro-Fuzzy Inference System (ANFIS). The DWT is employed to decompose the original signal in a set of subseries and then an ANFIS is used to generate the forecast for each subseries. The proposed hybrid method (DWT-ANFIS) was evaluated using a greenhouse energy demand data for a week and compared with ANFIS. The performances of the different models were evaluated by comparing the corresponding values of Mean Absolute Percentage Error (MAPE). It was demonstrated that discret wavelet transform can improve agricultural greenhouse energy demand modeling.Keywords: wavelet transform, ANFIS, energy consumption prediction, greenhouse
Procedia PDF Downloads 88625 Preparation of Nanocomposites Based on Biodegradable Polycaprolactone by Melt Mixture
Authors: Mohamed Amine Zenasni, Bahia Meroufel, André Merlin, Said Benfarhi, Stéphane Molina, Béatrice George
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The introduction of nano-fillers into polymers field lead to the creation of the nano composites. This creation is starting up a new revolution into the world of materials. Nano composites are similar to traditional composite of a polymer blend and filler with at least one nano-scopic dimension. In our project, we worked with nano composites of biodegradable polymer: polycaprolactone, combined with nano-clay (Maghnite) and with different nano-organo-clays. These nano composites have been prepared by melt mixture method. The advantage of this polymer is its degradability and bio compatibility. A study of the relationship between development, micro structure and physico chemical properties of nano composites, clays modified with 3-aminopropyltriethoxysilane (APTES) and Hexadecyltriméthy ammonium bromide (CTAB) and untreated clays were made. Melt mixture method is most suitable methods to get a better dispersion named exfoliation.Keywords: nanocomposite, biodegradable, polycaprolactone, maghnite, melt mixture, APTES, CTAB
Procedia PDF Downloads 434624 The Impact of Corporate Social Responsibility Information Disclosure on the Accuracy of Analysts' Earnings Forecasts
Authors: Xin-Hua Zhao
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In recent years, the growth rate of social responsibility reports disclosed by Chinese corporations has grown rapidly. The economic effects of the growing corporate social responsibility reports have become a hot topic. The article takes the chemical listed engineering corporations that disclose social responsibility reports in China as a sample, and based on the information asymmetry theory, examines the economic effect generated by corporate social responsibility disclosure with the method of ordinary least squares. The research is conducted from the perspective of analysts’ earnings forecasts and studies the impact of corporate social responsibility information disclosure on improving the accuracy of analysts' earnings forecasts. The results show that there is a statistically significant negative correlation between corporate social responsibility disclosure index and analysts’ earnings forecast error. The conclusions confirm that enterprises can reduce the asymmetry of social and environmental information by disclosing social responsibility reports, and thus improve the accuracy of analysts’ earnings forecasts. It can promote the effective allocation of resources in the market.Keywords: analysts' earnings forecasts, corporate social responsibility disclosure, economic effect, information asymmetry
Procedia PDF Downloads 156623 Synthesis and Characterization of Recycled Isotactic Polypropylene Nanocomposites Containing Date Wood Fiber
Authors: Habib Shaban
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Nanocomposites of isotactic polypropylene (iPP) and date wood fiber were prepared after modification of the host matrix by reactive extrusion grafting of maleic anhydride. Chemical and mechanical treatment of date wood flour (WF) was conducted to obtain nanocrystalline cellulose. Layered silicates (clay) were partially intercalated with date wood fiber, and the modified layered silicate was used as filler in the PP matrix via a melt-blending process. The tensile strength of composites prepared from wood fiber modified clay was greater than that of the iPP-clay and iPP-WF composites at a 6% filler concentration, whereas deterioration of mechanical properties was observed when clay and WF were used alone for reinforcement. The dispersion of the filler in the matrix significantly decreased after clay modification with cellulose at higher concentrations, as shown by X-ray diffraction (XRD) data.Keywords: nanocomposites, isotactic polypropylene, date wood flour, intercalated, melt-blending
Procedia PDF Downloads 384622 Energy-efficient Buildings In Construction Industry Using Fly Ash-based Geopolymer Technology
Authors: Maryam Kiani
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The aim of this study was to investigate the influence of nanoparticles additive on the properties of fly ash-based geopolymer. The geopolymer samples were prepared using fly ash as the primary source material, along with an alkali activator solution and different concentrations of carbon black additive. The effects of nanoparticles flexural strength, water absorption, and micro-structural properties of the cured samples. The results revealed that the inclusion of nanoparticles additive significantly enhanced the mechanical and electrical properties of the geopolymer binder. Micro-structural analysis using scanning electron microscopy (SEM) revealed a more compact and homogeneous structure in the geopolymer samples with nanoparticles. The dispersion of nanoparticles particles within the geopolymer matrix was observed, suggesting improved inter-particle bonding and increased density. Overall, this study demonstrates the positive impact of nanoparticles additive on the qualities of fly ash-based geopolymer, emphasizing its potential as an effective enhancer for geopolymer binder applications for the development of construction and infrastructure for energy buildings.Keywords: fly-ash, geopolymer, energy buildings, nanotechnology
Procedia PDF Downloads 91621 Short Term Distribution Load Forecasting Using Wavelet Transform and Artificial Neural Networks
Authors: S. Neelima, P. S. Subramanyam
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The major tool for distribution planning is load forecasting, which is the anticipation of the load in advance. Artificial neural networks have found wide applications in load forecasting to obtain an efficient strategy for planning and management. In this paper, the application of neural networks to study the design of short term load forecasting (STLF) Systems was explored. Our work presents a pragmatic methodology for short term load forecasting (STLF) using proposed two-stage model of wavelet transform (WT) and artificial neural network (ANN). It is a two-stage prediction system which involves wavelet decomposition of input data at the first stage and the decomposed data with another input is trained using a separate neural network to forecast the load. The forecasted load is obtained by reconstruction of the decomposed data. The hybrid model has been trained and validated using load data from Telangana State Electricity Board.Keywords: electrical distribution systems, wavelet transform (WT), short term load forecasting (STLF), artificial neural network (ANN)
Procedia PDF Downloads 436620 Composite Kernels for Public Emotion Recognition from Twitter
Authors: Chien-Hung Chen, Yan-Chun Hsing, Yung-Chun Chang
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The Internet has grown into a powerful medium for information dispersion and social interaction that leads to a rapid growth of social media which allows users to easily post their emotions and perspectives regarding certain topics online. Our research aims at using natural language processing and text mining techniques to explore the public emotions expressed on Twitter by analyzing the sentiment behind tweets. In this paper, we propose a composite kernel method that integrates tree kernel with the linear kernel to simultaneously exploit both the tree representation and the distributed emotion keyword representation to analyze the syntactic and content information in tweets. The experiment results demonstrate that our method can effectively detect public emotion of tweets while outperforming the other compared methods.Keywords: emotion recognition, natural language processing, composite kernel, sentiment analysis, text mining
Procedia PDF Downloads 218619 Remote Sensing Reversion of Water Depths and Water Management for Waterbird Habitats: A Case Study on the Stopover Site of Siberian Cranes at Momoge, China
Authors: Chunyue Liu, Hongxing Jiang
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Traditional water depth survey of wetland habitats used by waterbirds needs intensive labor, time and money. The optical remote sensing image relies on passive multispectral scanner data has been widely employed to study estimate water depth. This paper presents an innovative method for developing the water depth model based on the characteristics of visible and thermal infrared spectra of Landsat ETM+ image, combing with 441 field water depth data at Etoupao shallow wetland. The wetland is located at Momoge National Nature Reserve of Northeast China, where the largest stopover habitat along the eastern flyway of globally, critically-endangered Siberian Cranes are. The cranes mainly feed on the tubers of emergent aquatic plants such as Scirpus planiculmis and S. nipponicus. The effective water control is a critical step for maintaining the production of tubers and food availability for this crane. The model employing multi-band approach can effectively simulate water depth for this shallow wetland. The model parameters of NDVI and GREEN indicated the vegetation growth and coverage affecting the reflectance from water column change are uneven. Combining with the field-observed water level at the same date of image acquisition, the digital elevation model (DEM) for the underwater terrain was generated. The wetland area and water volume of different water levels were then calculated from the DEM using the function of Area and Volume Statistics under the 3D Analyst of ArcGIS 10.0. The findings provide good references to effectively monitor changes in water level and water demand, develop practical plan for water level regulation and water management, and to create best foraging habitats for the cranes. The methods here can be adopted for the bottom topography simulation and water management in waterbirds’ habitats, especially in the shallow wetlands.Keywords: remote sensing, water depth reversion, shallow wetland habitat management, siberian crane
Procedia PDF Downloads 252618 Tensile and Flexural Behavior of Particulate Filled/Polymer Matrix Composites
Authors: M. Alsaadi, A. Erkliğ, M. Bulut
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This paper experimentally investigates the flexural and tensile properties of the industrial wastes sewage sludge ash (SSA) and fly ash (FA), and conventional ceramic powder silicon carbide (SiC) filled polyester composites. Four weight fractions (5, 10, 15 and 20 wt%) for each micro filler were used for production of composites. Then, test samples were produced according to ASTM. The resulting degree of particle dispersion in the polymer matrix was visualized by using scanning electron microscope (SEM). Results from this study showed that the tensile strength increased up to its maximum value at filler content 5 wt% of SSA, FA and SiC. Flexural strength increased with addition of particulate filler up to its maximum value at filler content 5 wt% of SSA and FA while for SiC decreased for all weight fractions gradually. The addition of SSA, FA and SiC fillers resulted in increase of tensile and flexural modulus for all the particulate composites. Industrial waste SSA can be used as an additive with polymer to produce composite materials.Keywords: particle-reinforcement, sewage sludge ash, polymer matrix composites, mechanical properties
Procedia PDF Downloads 372617 Compressive Response of Unidirectional Basalt Fiber/Epoxy/MWCNTs Composites
Authors: Reza Eslami-Farsani, Hamed Khosravi
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The aim of this work is to study the influence of multi-walled carbon nanotubes (MWCNTs) addition at various contents with respect to the matrix (0-0.5 wt.% at a step of 0.1 wt.%) on the compressive response of unidirectional basalt fiber (UD-BF)/epoxy composites. Toward this end, MWCNTs were firstly functionalized with 3-glycidoxypropyltrimethoxysilane (3-GPTMS) to improve their dispersion state and interfacial compatibility with the epoxy. Subsequently, UD-BF/epoxy and multiscale 3-GPTMS-MWCNTs/UD-BF/epoxy composites were prepared. The mechanical properties of the composites were determined by quasi-static compression test. The compressive strength of the composites was obtained through performing the compression test on the off-axis specimens and extracting their longitudinal compressive strength. Results demonstrated that the highest value in compressive strength was attained at 0.4 wt.% MWCNTs with 41% increase, compared to the BF/epoxy composite. Potential mechanisms behind these were implied.Keywords: multiscale polymeric composites, unidirectional basalt fibers, multi-walled carbon nanotubes, surface modification, compressive properties
Procedia PDF Downloads 303616 Determination of the Optimal Content of Commercial Superplasticizer Additives in Cements with Calcined Clay
Authors: Amanda R. Teixeira, João H. S. Rego, Gabriel F. S. Brito, Fabricio M. Silva
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The use of superplasticizer additives has provided several advances for the civil construction industry, enabling gains in the rheological behavior and mechanical properties of cementitious matrices. These compounds act at the solid-liquid interface of colloidal suspensions of cement pastes, preventing agglomeration of the particles. Although the use in the concrete industry is wide, the mechanisms of dispersion of concrete admixtures composed of polycarboxylate in cement with supplementary cementitious materials have ample opportunity to be investigated, providing the attainment of increasingly compatible and efficient cement-addition-additive systems. The cements used in the research are Portland Cement CPV and two cements Portland Cement Composite (CPIV) with calcined clay contents of 20% and 28% and three commercial additives based on polycarboxylate. The performance of the additives and obtaining the optimal content was determined by the Marsh Cone test and spread by Mini-Slump.Keywords: calcined clay, composite cements, superplasticizer additives, polycarboxylate
Procedia PDF Downloads 106615 Reduce the Fire Hazards of Epoxy Resin by a Zinc Stannate and Graphene Hybrids
Authors: Haibo Sheng, Yuan Hu
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Spinel structure Zinc stannate (Zn2SnO4, ZS)/Graphene was successfully synthesized by a simple in situ hydrothermal route. Morphological study and structure analysis confirmed the homogenously loading of ZS on the graphene sheets. Then, the resulted ZS/graphene hybrids were incorporated into epoxy resin to form EP/ZS/graphene composites by a solvent dispersion method. Improved thermal stability was investigated by Thermogravimetric Analysis (TGA). Cone calorimeter result showed low peak heat release rate (PHRR). Toxical gases release during combustion was evaluated by a facile device organized in our lab. The results showed that the release of NOx, HCN decrease of about 55%. Also, TG-IR technology was used to investigate the gas release during the EP decomposition process. The CO release had decreased about 80%.The EP/G/ZS showed lowest hazards during combustion (including flame retardancy, thermal stability, lower toxical gases release and so on) than pure EP.Keywords: fire hazards, zinc stannate, epoxy resin, toxical gas hazards
Procedia PDF Downloads 182614 Fracture Strength of Carbon Nanotube Reinforced Plasma Sprayed Aluminum Oxide Coating
Authors: Anup Kumar Keshri, Arvind Agarwal
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Carbon nanotube (CNT) reinforced aluminum oxide (Al2O3) composite coating was synthesized on the steel substrate using plasma spraying technique. Three different compositions of coating such as Al2O3, Al2O¬3-4 wt. % CNT and Al2O3-8 wt. % CNT were synthesized and the fracture strength was determined using the four point bend test. Uniform dispersion of CNTs over Al2O3 powder particle was successfully achieved. With increasing CNT content, porosity in the coating showed decreasing trend and hence contributed towards enhanced mechanical properties such as hardness (~12% increased) and elastic modulus (~34 % increased). Fracture strength of the coating was found to be increasing with the CNT additions. By reinforcement of 8 wt. % of CNT, fracture strength increased by ~2.5 times. The improvement in fracture strength of Al2O3-CNT coating was attributed to three competitive phenomena viz. (i) lower porosity (ii) higher hardness and elastic modulus (iii) CNT bridging between splats.Keywords: aluminum oxide, carbon nanotube, fracture strength, plasma spraying
Procedia PDF Downloads 394613 Biosurfactants Produced by Antarctic Bacteria with Hydrocarbon Cleaning Activity
Authors: Claudio Lamilla, Misael Riquelme, Victoria Saez, Fernanda Sepulveda, Monica Pavez, Leticia Barrientos
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Biosurfactants are compounds synthesized by microorganisms that show various chemical structures, including glycolipids, lipopeptides, polysaccharide-protein complex, phospholipids, and fatty acids. These molecules have attracted attention in recent years due to the amphipathic nature of these compounds, which allows their application in various activities related to emulsification, foaming, detergency, wetting, dispersion and solubilization of hydrophobic compounds. Microorganisms that produce biosurfactants are ubiquitous, not only present in water, soil, and sediments but in extreme conditions of pH, salinity or temperature such as those present in Antarctic ecosystems. Due to this, it is of interest to study biosurfactants producing bacterial strains isolated from Antarctic environments, with the potential to be used in various biotechnological processes. The objective of this research was to characterize biosurfactants produced by bacterial strains isolated from Antarctic environments, with potential use in biotechnological processes for the cleaning of sites contaminated with hydrocarbons. The samples were collected from soils and sediments in the South Shetland Islands and the Antarctic Peninsula, during the Antarctic Research Expedition INACH 2016, from both pristine and human occupied areas (influenced). The bacteria isolation was performed from solid R2A, M1 and LB media. The selection of strains producing biosurfactants was done by hemolysis test on blood agar plates (5%) and blue agar (CTAB). From 280 isolates, it was determined that 10 bacterial strains produced biosurfactants after stimulation with different carbon sources. 16S rDNA taxonomic markers, using the universal primers 27F-1492R, were used to identify these bacterias. Biosurfactants production was carried out in 250 ml flasks using Bushnell Hass liquid culture medium enriched with different carbon sources (olive oil, glucose, glycerol, and hexadecane) during seven days under constant stirring at 20°C. Each cell-free supernatant was characterized by physicochemical parameters including drop collapse, emulsification and oil displacement, as well as stability at different temperatures, salinity, and pH. In addition, the surface tension of each supernatant was quantified using a tensiometer. The strains with the highest activity were selected, and the production of biosurfactants was stimulated in six liters of culture medium. Biosurfactants were extracted from the supernatants with chloroform methanol (2:1). These biosurfactants were tested against crude oil and motor oil, to evaluate their displacement activity (detergency). The characterization by physicochemical properties of 10 supernatants showed that 80% of them produced the drop collapse, 60% had stability at different temperatures, and 90% had detergency activity in motor and olive oil. The biosurfactants obtained from two bacterial strains showed a high activity of dispersion of crude oil and motor oil with halos superior to 10 cm. We can conclude that bacteria isolated from Antarctic soils and sediments provide biological material of high quality for the production of biosurfactants, with potential applications in the biotechnological industry, especially in hydrocarbons -contaminated areas such as petroleum.Keywords: antarctic, bacteria, biosurfactants, hydrocarbons
Procedia PDF Downloads 279612 Assessment of Pollution of the Rustavi City’s Atmosphere with Microaerosols
Authors: Natia Gigauri, Aleksandre Surmava
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According to observational data, experimental measurements, and numerical modeling, is assessed pollution of one of the industrial centers of Georgia, Rustavi city’s atmosphere with microaerosols. Monthly, daily and hourly changes of the concentrations of PM2.5 and PM10 in the city atmosphere are analyzed. It is accepted that PM2.5 concentrations are always lower than PM10 concentrations, but their change curve is the same. In addition, it has been noted that the maximum concentrations of particles in the atmosphere of Rustavi city will be reached at any part of the day, which is determined by the total impact of the traffic flow and industrial facilities. By numerical modeling has calculated the influence of background western light air and gentle and fresh breeze on the distribution of PM particles in the atmosphere. Calculations showed that background light air and gentle breeze lead to an increase the concentrations of microaerosols in the city's atmosphere, while fresh breeze contribute to the dispersion of dusty clouds. As a result, the level of dust in the city is decreasing, but the distribution area is expanding.Keywords: pollution, modelling, PM2.5, PM10, experimental measurement
Procedia PDF Downloads 89611 Forecast Based on an Empirical Probability Function with an Adjusted Error Using Propagation of Error
Authors: Oscar Javier Herrera, Manuel Angel Camacho
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This paper addresses a cutting edge method of business demand forecasting, based on an empirical probability function when the historical behavior of the data is random. Additionally, it presents error determination based on the numerical method technique ‘propagation of errors’. The methodology was conducted characterization and process diagnostics demand planning as part of the production management, then new ways to predict its value through techniques of probability and to calculate their mistake investigated, it was tools used numerical methods. All this based on the behavior of the data. This analysis was determined considering the specific business circumstances of a company in the sector of communications, located in the city of Bogota, Colombia. In conclusion, using this application it was possible to obtain the adequate stock of the products required by the company to provide its services, helping the company reduce its service time, increase the client satisfaction rate, reduce stock which has not been in rotation for a long time, code its inventory, and plan reorder points for the replenishment of stock.Keywords: demand forecasting, empirical distribution, propagation of error, Bogota
Procedia PDF Downloads 630610 A Mobile Application for Analyzing and Forecasting Crime Using Autoregressive Integrated Moving Average with Artificial Neural Network
Authors: Gajaanuja Megalathan, Banuka Athuraliya
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Crime is one of our society's most intimidating and threatening challenges. With the majority of the population residing in cities, many experts and data provided by local authorities suggest a rapid increase in the number of crimes committed in these cities in recent years. There has been an increasing graph in the crime rates. People living in Sri Lanka have the right to know the exact crime rates and the crime rates in the future of the place they are living in. Due to the current economic crisis, crime rates have spiked. There have been so many thefts and murders recorded within the last 6-10 months. Although there are many sources to find out, there is no solid way of searching and finding out the safety of the place. Due to all these reasons, there is a need for the public to feel safe when they are introduced to new places. Through this research, the author aims to develop a mobile application that will be a solution to this problem. It is mainly targeted at tourists, and people who recently relocated will gain advantage of this application. Moreover, the Arima Model combined with ANN is to be used to predict crime rates. From the past researchers' works, it is evidently clear that they haven’t used the Arima model combined with Artificial Neural Networks to forecast crimes.Keywords: arima model, ANN, crime prediction, data analysis
Procedia PDF Downloads 131609 Predictive Maintenance of Electrical Induction Motors Using Machine Learning
Authors: Muhammad Bilal, Adil Ahmed
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This study proposes an approach for electrical induction motor predictive maintenance utilizing machine learning algorithms. On the basis of a study of temperature data obtained from sensors put on the motor, the goal is to predict motor failures. The proposed models are trained to identify whether a motor is defective or not by utilizing machine learning algorithms like Support Vector Machines (SVM) and K-Nearest Neighbors (KNN). According to a thorough study of the literature, earlier research has used motor current signature analysis (MCSA) and vibration data to forecast motor failures. The temperature signal methodology, which has clear advantages over the conventional MCSA and vibration analysis methods in terms of cost-effectiveness, is the main subject of this research. The acquired results emphasize the applicability and effectiveness of the temperature-based predictive maintenance strategy by demonstrating the successful categorization of defective motors using the suggested machine learning models.Keywords: predictive maintenance, electrical induction motors, machine learning, temperature signal methodology, motor failures
Procedia PDF Downloads 117608 Broadcast Routing in Vehicular Ad hoc Networks (VANETs)
Authors: Muazzam A. Khan, Muhammad Wasim
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Vehicular adhoc network (VANET) Cars for network (VANET) allowing vehicles to talk to each other, which is committed to building a strong network of mobile vehicles is technical. In VANETs vehicles are equipped with special devices that can get and share info with the atmosphere and other vehicles in the network. Depending on this data security and safety of the vehicles can be enhanced. Broadcast routing is dispersion of any audio or visual medium of mass communication scattered audience distribute audio and video content, but usually using electromagnetic radiation (waves). The lack of server or fixed infrastructure media messages in VANETs plays an important role for every individual application. Broadcast Message VANETs still open research challenge and requires some effort to come to good solutions. This paper starts with a brief introduction of VANET, its applications, and the law of the message-trends in this network starts. This work provides an important and comprehensive study of reliable broadcast routing in VANET scenario.Keywords: vehicular ad-hoc network , broadcasting, networking protocols, traffic pattern, low intensity conflict
Procedia PDF Downloads 532607 Investigation of Polymer Composite for High Dose Dosimetry
Authors: Esther Lorrayne M. Pereira, Adriana S. M. Batista, Fabíola A. S. Ribeiro, Adelina P. Santos, Luiz O. Faria
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In this work we have prepared nanocomposites made by mixing Poli (vinilidene fluoride) (PVDF), zirconium oxide (ZrO₂) and multi–walled carbon nanotubes (MWCNTs) aiming to find dosimetric properties for applications in high dose dosimetry. The samples were irradiated with a Co-60 source at constant dose rate (16.7 kGy/h), with doses ranging from 100 to 2750 kGy. The UV-Vis and FTIR spectrophotometry have been used to monitor the appearing of C=C conjugated bonds and radio-oxidation of carbon (C=O). FTIR spectrometry has that the absorbance intensities at 1715 cm⁻¹ and 1730 cm⁻¹ can be used for high dosimetry purposes for gamma doses ranging from 500 to 2750 kGy. In this range, it is possible to observe a linear relationship between Abs & Dose. Fading of signal was evaluated for one month and reproducibility in 2000 kGy dose. Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) was used for evaluated the dispersion ZrO₂ and MWCNT in the matrix of the PVDF.Keywords: polymer, composite, high dose dosimetry, PVDF/ZrO₂/MWCNT
Procedia PDF Downloads 288606 Critical Appraisal of Different Drought Indices of Drought Predection and Their Application in KBK Districts of Odisha
Authors: Bibhuti Bhusan Sahoo, Ramakar Jha
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Mapping of the extreme events (droughts) is one of the adaptation strategies to consequences of increasing climatic inconsistency and climate alterations. There is no operational practice to forecast the drought. One of the suggestions is to update mapping of drought prone areas for developmental planning. Drought indices play a significant role in drought mitigation. Many scientists have worked on different statistical analysis in drought and other climatological hazards. Many researchers have studied droughts individually for different sub-divisions or for India. Very few workers have studied district wise probabilities over large scale. In the present study, district wise drought probabilities over KBK (Kalahandi-Balangir-Koraput) districts of Odisha, India, Which are seriously prone to droughts, has been established using Hydrological drought index and Meteorological drought index along with the remote sensing drought indices to develop a multidirectional approach in the field of drought mitigation. Mapping for moderate and severe drought probabilities for KBK districts has been done and regions belonging different class intervals of probabilities of drought have been demarcated. Such type of information would be a good tool for planning purposes, for input in modelling and better promising results can be achieved.Keywords: drought indices, KBK districts, proposed drought severity index, SPI
Procedia PDF Downloads 449605 Study of Biodegradable Composite Materials Based on Polylactic Acid and Vegetal Reinforcements
Authors: Manel Hannachi, Mustapha Nechiche, Said Azem
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This study focuses on biodegradable materials made from Poly-lactic acid (PLA) and vegetal reinforcements. Three materials are developed from PLA, as a matrix, and : (i) olive kernels (OK); (ii) alfa (α) short fibers and (iii) OK+ α mixture, as reinforcements. After processing of PLA pellets and olive kernels in powder and alfa stems in short fibers, three mixtures, namely PLA-OK, PLA-α, and PLA-OK-α are prepared and homogenized in Turbula®. These mixtures are then compacted at 180°C under 10 MPa during 15 mn. Scanning Electron Microscopy (SEM) examinations show that PLA matrix adheres at surface of all reinforcements and the dispersion of these ones in matrix is good. X-ray diffraction (XRD) analyses highlight an increase of PLA inter-reticular distances, especially for the PLA-OK case. These results are explained by the dissociation of some molecules derived from reinforcements followed by diffusion of the released atoms in the structure of PLA. This is consistent with Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) analysis results.Keywords: alfa short fibers, biodegradable composite, olive kernels, poly-lactic acid
Procedia PDF Downloads 147604 South African Multiple Deprivation-Concentration Index Quantiles Differentiated by Components of Success and Impediment to Tuberculosis Control Programme Using Mathematical Modelling in Rural O. R. Tambo District Health Facilities
Authors: Ntandazo Dlatu, Benjamin Longo-Mbenza, Andre Renzaho, Ruffin Appalata, Yolande Yvonne Valeria Matoumona Mavoungou, Mbenza Ben Longo, Kenneth Ekoru, Blaise Makoso, Gedeon Longo Longo
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Background: The gap between complexities related to the integration of Tuberculosis /HIV control and evidence-based knowledge motivated the initiation of the study. Therefore, the objective of this study was to explore correlations between national TB management guidelines, multiple deprivation indexes, quantiles, components and levels of Tuberculosis control programme using mathematical modeling in rural O.R. Tambo District Health Facilities, South Africa. Methods: The study design used mixed secondary data analysis and cross-sectional analysis between 2009 and 2013 across O.R Tambo District, Eastern Cape, South Africa using univariate/ bivariate analysis, linear multiple regression models, and multivariate discriminant analysis. Health inequalities indicators and component of an impediment to the tuberculosis control programme were evaluated. Results: In total, 62 400 records for TB notification were analyzed for the period 2009-2013. There was a significant but negative between Financial Year Expenditure (r= -0.894; P= 0.041) Seropositive HIV status(r= -0.979; P= 0.004), Population Density (r = -0.881; P= 0.048) and the number of TB defaulter in all TB cases. It was shown unsuccessful control of TB management program through correlations between numbers of new PTB smear positive, TB defaulter new smear-positive, TB failure all TB, Pulmonary Tuberculosis case finding index and deprivation-concentration-dispersion index. It was shown successful TB program control through significant and negative associations between declining numbers of death in co-infection of HIV and TB, TB deaths all TB and SMIAD gradient/ deprivation-concentration-dispersion index. The multivariate linear model was summarized by unadjusted r of 96%, adjusted R2 of 95 %, Standard Error of estimate of 0.110, R2 changed of 0.959 and significance for variance change for P=0.004 to explain the prediction of TB defaulter in all TB with equation y= 8.558-0.979 x number of HIV seropositive. After adjusting for confounding factors (PTB case finding the index, TB defaulter new smear-positive, TB death in all TB, TB defaulter all TB, and TB failure in all TB). The HIV and TB death, as well as new PTB smear positive, were identified as the most important, significant, and independent indicator to discriminate most deprived deprivation index far from other deprivation quintiles 2-5 using discriminant analysis. Conclusion: Elimination of poverty such as overcrowding, lack of sanitation and environment of highest burden of HIV might end the TB threat in O.R Tambo District, Eastern Cape, South Africa. Furthermore, ongoing adequate budget comprehensive, holistic and collaborative initiative towards Sustainable Developmental Goals (SDGs) is necessary for complete elimination of TB in poor O.R Tambo District.Keywords: tuberculosis, HIV/AIDS, success, failure, control program, health inequalities, South Africa
Procedia PDF Downloads 170603 Analysis of Photic Zone’s Summer Period-Dissolved Oxygen and Temperature as an Early Warning System of Fish Mass Mortality in Sampaloc Lake in San Pablo, Laguna
Authors: Al Romano, Jeryl C. Hije, Mechaela Marie O. Tabiolo
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The decline in water quality is a major factor in aquatic disease outbreaks and can lead to significant mortality among aquatic organisms. Understanding the relationship between dissolved oxygen (DO) and water temperature is crucial, as these variables directly impact the health, behavior, and survival of fish populations. This study investigated how DO levels, water temperature, and atmospheric temperature interact in Sampaloc Lake to assess the risk of fish mortality. By employing a combination of linear regression models and machine learning techniques, researchers developed predictive models to forecast DO concentrations at various depths. The results indicate that while DO levels generally decrease with depth, the predicted concentrations are sufficient to support the survival of common fish species in Sampaloc Lake during March, April, and May 2025.Keywords: aquaculture, dissolved oxygen, water temperature, regression analysis, machine learning, fish mass mortality, early warning system
Procedia PDF Downloads 35602 Comparative Study of Soliton Collisions in Uniform and Nonuniform Magnetized Plasma
Authors: Renu Tomar, Hitendra K. Malik, Raj P. Dahiya
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Similar to the sound waves in air, plasmas support the propagation of ion waves, which evolve into the solitary structures when the effect of non linearity and dispersion are balanced. The ion acoustic solitary waves have been investigated in details in homogeneous plasmas, inhomogeneous plasmas, and magnetized plasmas. The ion acoustic solitary waves are also found to reflect from a density gradient or boundary present in the plasma after propagating. Another interesting feature of the solitary waves is their collision. In the present work, we carry out analytical calculations for the head-on collision of solitary waves in a magnetized plasma which has dust grains in addition to the ions and electrons. For this, we employ Poincar´e-Lighthill-Kuo (PLK) method. To lowest nonlinear order, the problem of colliding solitary waves leads to KdV (modified KdV) equations and also yields the phase shifts that occur in the interaction. These calculations are accomplished for the uniform and nonuniform plasmas, and the results on the soliton properties are discussed in detail.Keywords: inhomogeneous magnetized plasma, dust charging, soliton collisions, magnetized plasma
Procedia PDF Downloads 469601 Reservoir Fluids: Occurrence, Classification, and Modeling
Authors: Ahmed El-Banbi
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Several PVT models exist to represent how PVT properties are handled in sub-surface and surface engineering calculations for oil and gas production. The most commonly used models include black oil, modified black oil (MBO), and compositional models. These models are used in calculations that allow engineers to optimize and forecast well and reservoir performance (e.g., reservoir simulation calculations, material balance, nodal analysis, surface facilities, etc.). The choice of which model is dependent on fluid type and the production process (e.g., depletion, water injection, gas injection, etc.). Based on close to 2,000 reservoir fluid samples collected from different basins and locations, this paper presents some conclusions on the occurrence of reservoir fluids. It also reviews the common methods used to classify reservoir fluid types. Based on new criteria related to the production behavior of different fluids and economic considerations, an updated classification of reservoir fluid types is presented in the paper. Recommendations on the use of different PVT models to simulate the behavior of different reservoir fluid types are discussed. Each PVT model requirement is highlighted. Available methods for the calculation of PVT properties from each model are also discussed. Practical recommendations and tips on how to control the calculations to achieve the most accurate results are given.Keywords: PVT models, fluid types, PVT properties, fluids classification
Procedia PDF Downloads 72600 A Literature Review on Development of a Forecast Supported Approach for the Continuous Pre-Planning of Required Transport Capacity for the Design of Sustainable Transport Chains
Authors: Georg Brunnthaller, Sandra Stein, Wilfried Sihn
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Logistics service providers are facing increasing volatility concerning future transport demand. Short-term planning horizons and planning uncertainties lead to reduced capacity utilisation and increasing empty mileage. To overcome these challenges, a model is proposed to continuously pre-plan future transport capacity in order to redesign and adjust the intermodal fleet accordingly. It is expected that the model will enable logistics service providers to organise more economically and ecologically sustainable transport chains in a more flexible way. To further describe such planning aspects, this paper gives a structured literature review on transport planning problems. The focus is on strategic and tactical planning levels, comprising relevant fleet-sizing-, network-design- and choice-of-carriers-problems. Models and their developed solution techniques are presented and the literature review is concluded with an outlook to our future research objectivesKeywords: choice of transport mode, fleet-sizing, freight transport planning, multimodal, review, service network design
Procedia PDF Downloads 364599 Anticorrosive Polyurethane Clear Coat with Self-Cleaning Character
Authors: Nihit Madireddi, P. A. Mahanwar
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We have aimed to produce a self-cleaning transparent polymer coating with polyurethane (PU) matrix as the latter is highly solvent, chemical and weather resistant having good mechanical properties. Nano-silica modified by 1H, 1H, 2H, 2H-perflurooctyltriethoxysilane was incorporated into the PU matrix for attaining self-cleaning ability through hydrophobicity. The modification was confirmed by particle size analysis and scanning electron microscopy (SEM). Thermo-gravimetric (TGA) studies were carried to ascertain the grafting of silane onto the silica. Several coating formulations were prepared by varying the silica loading content and compared to a commercial equivalent. The effect of dispersion and the morphology of the coated films were assessed by SEM analysis. All coating standardized tests like solvent resistance, adhesion, flexibility, acid, alkali, gloss etc. have been performed as per ASTM standards. Water contact angle studies were conducted to analyze the hydrophobic character of the coating. In addition, the coatings were also subjected to salt spray and accelerated weather testing to analyze the durability of the coating.Keywords: FAS, nano-silica, PU clear coat, self-cleaning
Procedia PDF Downloads 311598 Thulium Laser Design and Experimental Verification for NIR and MIR Nonlinear Applications in Specialty Optical Fibers
Authors: Matej Komanec, Tomas Nemecek, Dmytro Suslov, Petr Chvojka, Stanislav Zvanovec
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Nonlinear phenomena in the near- and mid-infrared region are attracting scientific attention mainly due to the supercontinuum generation possibilities and subsequent utilizations for ultra-wideband applications like e.g. absorption spectroscopy or optical coherence tomography. Thulium-based fiber lasers provide access to high-power ultrashort pump pulses in the vicinity of 2000 nm, which can be easily exploited for various nonlinear applications. The paper presents a simulation and experimental study of a pulsed thulium laser based for near-infrared (NIR) and mid-infrared (MIR) nonlinear applications in specialty optical fibers. In the first part of the paper the thulium laser is discussed. The thulium laser is based on a gain-switched seed-laser and a series of amplification stages for obtaining output peak powers in the order of kilowatts for pulses shorter than 200 ps in full-width at half-maximum. The pulsed thulium laser is first studied in a simulation software, focusing on seed-laser properties. Afterward, a pre-amplification thulium-based stage is discussed, with the focus of low-noise signal amplification, high signal gain and eliminating pulse distortions during pulse propagation in the gain medium. Following the pre-amplification stage a second gain stage is evaluated with incorporating a thulium-fiber of shorter length with increased rare-earth dopant ratio. Last a power-booster stage is analyzed, where the peak power of kilowatts should be achieved. Examples of analytical study are further validated by the experimental campaign. The simulation model is further corrected based on real components – parameters such as real insertion-losses, cross-talks, polarization dependencies, etc. are included. The second part of the paper evaluates the utilization of nonlinear phenomena, their specific features at the vicinity of 2000 nm, compared to e.g. 1550 nm, and presents supercontinuum modelling, based on the thulium laser pulsed output. Supercontinuum generation simulation is performed and provides reasonably accurate results, once fiber dispersion profile is precisely defined and fiber nonlinearity is known, furthermore input pulse shape and peak power must be known, which is assured thanks to the experimental measurement of the studied thulium pulsed laser. The supercontinuum simulation model is put in relation to designed and characterized specialty optical fibers, which are discussed in the third part of the paper. The focus is placed on silica and mainly on non-silica fibers (fluoride, chalcogenide, lead-silicate) in their conventional, microstructured or tapered variants. Parameters such as dispersion profile and nonlinearity of exploited fibers were characterized either with an accurate model, developed in COMSOL software or by direct experimental measurement to achieve even higher precision. The paper then combines all three studied topics and presents a possible application of such a thulium pulsed laser system working with specialty optical fibers.Keywords: nonlinear phenomena, specialty optical fibers, supercontinuum generation, thulium laser
Procedia PDF Downloads 321