Search results for: bone engineering

Authors: Shivani Kolarkar

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Splendid growth in Indian IT has generated women employment on a large scale in India and continues to do it. Indian IT industry has achieved this in spite of total masculine dominance in other Indian engineering industries, where the ratio of women employment is almost negligible as compared to men. Indian IT today proudly enjoys a strong pool of technically educated, intellectual, and skillful women employees. IT industry has encouraged technical education for women in India, to a great extent. The software industry has definitely contributed to developing a positive and dignified role and status of women employees in Indian IT industry. It has promoted women’s social and economic role and status. In spite of all, gender discrimination still persists in Indian IT, also, which is low as compared to other industries, but it is a matter of concern. An Indian woman is bound to carry dual roles which are equally over-stressed for IT women employees. Long working hours, night shifts, work pressures and insufficient safety majors and necessary facilities for women contributes to making her physical-mental life, family and married life troublesome. Which forces her either to cluster at low-end jobs in IT/elsewhere or to sacrifice her career. Nature, role and status of HRM needs to be broadened, deepened and shaped into research-oriented multidimensional perspective in the context of really enhancing role and status of Indian IT women with high appreciation of women employees’ dignity and entity.

Keywords: attrition, gender discrimination, HRM, Indian IT, software industry, job satisfaction, safety, technical education, women employment

Procedia PDF Downloads 646

Authors: Mingjun Xu, Shouxiang Lu

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Understanding the interaction mechanism between the water droplet and pool fire has an important significance in engineering application of water sprinkle/spray/mist fire suppression. The micro impact process is unclear when the droplet impacts on the burning liquid surface at present. To deepen the understanding of the mechanisms of pool fire suppression with water spray/mist, dynamic processes of single water droplet impinging onto a hot heptane surface are visualized with the aid of a high-speed digital camera at 2000 fps. Each test is repeated 20 times. The water droplet diameter is around 1.98 mm, and the impact Weber number ranges from 30 to 695. The heptane is heated by a hot plate to mimic the burning condition, and the temperature varies from 30 to 90°C. The results show that three typical phenomena, including penetration, crater-jet and surface bubble, are observed, and the pool temperature has a significant influence on the critical condition for the appearance of each phenomenon. A global picture of different phenomena is built according to impact Weber number and pool temperature. In addition, the pool temperature and Weber number have important influences on the characteristic parameters including maximum crater depth, crown height and liquid column height. For a fixed Weber number, the liquid column height increases with pool temperature.

Keywords: droplet impact, fire suppression, hot surface, water spray

Procedia PDF Downloads 243

Authors: Shervin Khazaeli, Shahab Haj-zamani

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Recently, advanced geotechnical engineering problems related to soil movement, particle loss, and modeling of local failure (i.e. discontinua) as well as modeling the in-contact structures (i.e. continua) are of the great interest among researchers. The aim of this research is to meet the requirements with respect to the modeling of the above-mentioned two different domains simultaneously. To this end, a coupled numerical method is introduced based on Discrete Element Method (DEM) and eXtended-Finite Element Method (X-FEM). In the coupled procedure, DEM is employed to capture the interactions and relative movements of soil particles as discontinua, while X-FEM is utilized to model in-contact structures as continua, which may consist of different types of discontinuities. For verification purposes, the new coupled approach is utilized to examine benchmark problems including different contacts between/within continua and discontinua. Results are validated by comparison with those of existing analytical and numerical solutions. This study proves that extended-finite-discrete element method can be used to robustly analyze not only contact problems, but also other types of discontinuities in continua such as (i) crack formations and propagations, (ii) voids and bimaterial interfaces, and (iii) combination of previous cases. In essence, the proposed method can be used vastly in advanced soil-structure interaction problems to investigate the micro and macro behaviour of the surrounding soil and the response of the embedded structure that contains discontinuities.

Keywords: contact problems, discrete element method, extended-finite element method, soil-structure interaction

Procedia PDF Downloads 505

Authors: Xiaoming Yang, Abby Folberg, Carey Ryan, Lwetzel, Tgoering

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We examined gender differences in entrepreneurial career interests drawing on goal congruity theory, which posits that people adopt gender-stereotypic goal orientations in response to social pressures to conform to traditional gender roles. Aspiring entrepreneurs (N = 351) first wrote three to five sentences about what they believed made an entrepreneur successful. They then completed measures of agentic and communal goal orientations (i.e., male and female stereotypic orientations, respectively) and indicated their interests in starting ventures in stereotypically feminine (e.g., salon), masculine (e.g., auto-repair) and science, technology, engineering, and mathematics (STEM; e.g., software developer) ventures. Qualitative analyses demonstrated that participants ascribed agentic and, more specifically, dominance, attributes to entrepreneurs; few participants ascribed communal attributes (e.g., warmth). Bifactor structural equation modeling indicated that, as expected, agentic goal orientations included dimensions of competence, self-direction, and dominance orientations and communal goal orientations were unidimensional. Further, as expected, dominance and communal orientations partially accounted for gender differences in all three career types. We discuss implications for entrepreneurial education and practice from a goal congruity perspective and the use of bifactor modeling to improve the measurement of goal orientations.

Keywords: gender, entrepreneurship, gender stereotypes, agentic and communal goal orientations, entrepreneurship education

Procedia PDF Downloads 97

Authors: Nurlan Akhmetov, Abilmansur Yeshmuratov, Aliya Kurbanova, Gulnar Sugurbekova, Murat Baisariyev

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Extraction of the vanadium and nickel compounds is complex due to the high stability of porphyrin, nickel is catalytic poison which deactivates catalysis during the catalytic cracking of the oil, while vanadyl is abrasive and valuable metal. Thus, high concentration of the Ni and V in the crude oil makes their removal relevant. Two methods of the demetallization of crude oil were tested, therefore, the present research is conducted for comparative analysis of the deasphalting with organic solvents (cyclohexane, carbon tetrachloride, chloroform) and electrochemical method. Percentage of Ni extraction reached maximum of approximately 55% by using the electrochemical method in electrolysis cell, which was developed for this research and consists of three sections: oil and protonating agent (EtOH) solution between two conducting membranes which divides it from two capsules of 10% sulfuric acid and two graphite electrodes which cover all three parts in electrical circuit. Ions of metals pass through membranes and remain in acid solutions. The best result was obtained in 60 minutes with ethanol to oil ratio 25% to 75% respectively, current fits in to the range from 0.3A to 0.4A, voltage changed from 12.8V to 17.3V. Maximum efficiency of deasphalting, with cyclohexane as the solvent, in Soxhlet extractor was 66.4% for Ni and 51.2% for V. Thus, applying the voltammetry, ICP MS (Inductively coupled plasma mass spectrometry) and AAS (atomic absorption spectroscopy), these mentioned types of metal extraction methods were compared in this paper.

Keywords: electrochemistry, deasphalting of crude oil, demetallization of crude oil, petrolium engineering

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Authors: Ji Hun Choi, Seung Un Chae, Kyeong Suk Cho

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Synthetic resins are widely used in various fields including electricity, engineering, construction and agriculture. Many of interior and exterior finishing materials for buildings are synthetic resin products. In this study, full-scale fire tests were conducted on polyvinyl chloride, polypropylene and urethane in accordance with the “ISO 9705: Fire test - Full-scale room test for surface products” to measure heat release rate, toxic gas emission and smoke production rate. Based on the tests, fire growth pattern and fire risk were analyzed. Findings from the tests conducted on polyvinyl chloride and urethane are as follows. The total heat release rate and total smoke production rate of polyvinyl chloride were 98.89MW and 5284.41m2, respectively and its highest CO2 concentration was 0.149%. The values obtained from the test with urethane were 469.94 MW, 3396.28 m2 and 1.549%. While heat release rate and CO2 concentration were higher in urethane implying its high combustibility, smoke production rate was 1.5 times higher in polyvinyl chloride. Follow-up tests are planned to be conducted to accumulate data for the evaluation of heat emission and fire risk associated with synthetic resins.

Keywords: synthetic resins, fire test, full-scale test, heat release rate, smoke production rate, polyvinyl chloride, polypropylene, urethane

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Authors: Michael G. Pantelyat

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Fundamental basics of pure and applied research in the area of magneto-thermo-mechanical numerical analysis and design of innovative electromagnetic devices (modern induction heaters, novel thermoelastic actuators, rotating electrical machines, induction cookers, electrophysical devices) are elaborated. Thus, mathematical models of magneto-thermo-mechanical processes in electromagnetic devices taking into account main interactions of interrelated phenomena are developed. In addition, graphical representation of coupled (multiphysics) phenomena under consideration is proposed. Besides, numerical techniques for nonlinear problems solution are developed. On this base, effective numerical algorithms for solution of actual problems of practical interest are proposed, validated and implemented in applied 2D and 3D computer codes developed. Many applied problems of practical interest regarding modern electrical engineering devices are numerically solved. Investigations of the influences of various interrelated physical phenomena (temperature dependences of material properties, thermal radiation, conditions of convective heat transfer, contact phenomena, etc.) on the accuracy of the electromagnetic, thermal and structural analyses are conducted. Important practical recommendations on the choice of rational structures, materials and operation modes of electromagnetic devices under consideration are proposed and implemented in industry.

Keywords: electromagnetic devices, multiphysics, numerical analysis, simulation and design

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Authors: S. Sakthivel

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Currently, the global economy is based on the hydrocarbon economy, which is referencing the global hydrocarbon industry. Problems of using these fossil fuels (like oil, NG, coal) are emitting greenhouse gases (GHGs) and price fluctuation, supply/distribution, etc. These challenges can be overcome by using clean energy as hydrogen. The hydrogen economy is the use of hydrogen as a low carbon fuel, particularly for hydrogen vehicles, alternative industrial feedstock, power generation, and energy storage, etc. Engineering consulting firms have a significant role in this ambition and green hydrogen value chain (i.e., integration of renewables, production, storage, and distribution to end-users). Typically, the cost of green hydrogen is a function of the price of electricity needed, the cost of the electrolyser, and the operating cost to run the system. This article focuses on economic viability and explores the alluring business scenarios globally. Break-even analysis was carried out for green hydrogen production and in order to evaluate and compare the impact of the electricity price on the production costs of green hydrogen and relate it to fossil fuel-based brown/grey/blue hydrogen costs. It indicates that the cost of green hydrogen production will fall drastically due to the declining costs of renewable electricity prices and along with the improvement and scaling up of electrolyser manufacturing. For instance, in a scenario where electricity prices are below US$ 40/MWh, green hydrogen cost is expected to reach cost competitiveness.

Keywords: green hydrogen, cost analysis, break-even analysis, renewables, electrolyzer

Procedia PDF Downloads 143

Authors: Reza Mohammadzadeh

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The major challenges in geotechnical engineering in underground spaces arise from uncertainties and different probabilities. The collection, collation, and collaboration of existing data to incorporate them in analysis and design for given prospect evaluation would be a reliable, practical problem solving method under uncertainty. Machine learning (ML) is a subfield of artificial intelligence in statistical science which applies different techniques (e.g., Regression, neural networks, support vector machines, decision trees, random forests, genetic programming, etc.) on data to automatically learn and improve from them without being explicitly programmed and make decisions and predictions. In this paper, a conceptual database schema of geotechnical risks in underground coal mining based on a cloud system architecture has been designed. A new approach of risk assessment using a three-dimensional risk matrix supported by the level of knowledge (LoK) has been proposed in this model. Subsequently, the model workflow methodology stages have been described. In order to train data and LoK models deployment, an ML platform has been implemented. IBM Watson Studio, as a leading data science tool and data-driven cloud integration ML platform, is employed in this study. As a Use case, a data set of geotechnical hazards and risk assessment in underground coal mining were prepared to demonstrate the performance of the model, and accordingly, the results have been outlined.

Keywords: data model, geotechnical risks, machine learning, underground coal mining

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Authors: Jyoti Singh, Swati Dubey, Mukta Singh, R. P. Singh

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The freshwater microalgae Chlorella sp. is alluring considerable interest as a source for biofuel production due to its fast growth rate and high lipid content. Under nitrogen limited conditions, they can accumulate significant amounts of lipids. Thus, it is important to gain insight into the molecular mechanism of their lipid metabolism. In this study under nitrogen limited conditions, regular pattern of growth characteristics lipid accumulation and gene expression analysis of key regulatory genes of lipid biosynthetic pathway were carried out in microalgae Chlorella sp 3. Our results indicated that under nitrogen limited conditions there is a significant increase in the lipid content and lipid productivity, achieving 44.21±2.64 % and 39.34±0.66 mg/l/d at the end of the cultivation, respectively. Time-course transcript patterns of lipid biosynthesis genes i.e. acetyl coA carboxylase (accD) and diacylglycerol acyltransferase (dgat) showed that during late log phase of microalgae Chlorella sp.3 both the genes were significantly up regulated as compared to early log phase. Moreover, the transcript level of the dgat gene is two-fold higher than the accD gene. The results suggested that both the genes responded sensitively to the nitrogen limited conditions during the late log stage, which proposed their close relevance to lipid biosynthesis. Further, this transcriptome data will be useful for engineering microalgae species by targeting these genes for genetic modification to improve microalgal biofuel quality and production.

Keywords: biofuel, gene, lipid, microalgae

Procedia PDF Downloads 307

Authors: Gebreegziabher Hailu

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This paper presents the development of residual power series methods aimed at efficiently solving stiff differential equations, which pose significant challenges in numerical analysis due to their rapid changes in solution behavior. The RPSM is a numerical approach that generates polynomial-based approximate solutions without the need for linearization, discretization, or perturbation techniques, making it straightforward to implement and less prone to computational errors. We introduce an approach that utilizes power series expansions combined with residual minimization techniques to enhance convergence and stability. By analyzing the theoretical foundations of stiffness, we delve into the formulation of the residual power series method, detailing how it effectively captures the dynamics of stiff systems while maintaining computational efficiency. Numerical experiments demonstrate the method's superiority in terms of accuracy and computational cost when compared to traditional methods like implicit Runge-Kutta or multistep techniques. We also explore adaptive strategies within our framework to automatically adjust parameters based on the stiffness characteristics of the problem at hand. Ultimately, our findings contribute to the broader toolkit for tackling stiff differential equations, offering a robust alternative that promises to streamline computational workflows in various applied mathematics and engineering contexts.

Keywords: residual power series methods, stiff differential equoations, numerical approach, Runge Kutta methods

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Authors: Rula D. Alshareef, Safa S. Alqathmi, Ghadah K. Alkhouldi, Reem O. Bagabas, Farheen B. Hasan

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Safety engineering is among the most crucial considerations in any work environment. Providing mentally, physically, and environmentally safe work conditions must be the top priority of any successful organization. Company X is a local paint production company in Saudi Arabia; in a month, the factory experienced two significant accidents, which indicates that workers’ safety is overlooked. The aim of the research is to examine the risks, assess the root causes and recommend control measures that will eventually contribute to providing a safe workplace. The methodology used is sectioned into three phases, risk identification, assessment, and finally, mitigation. In the identification phase, the team used Rapid Entire Body Assessment (REBA) and National Institute for Occupational Safety and Health Lifting Index (NIOSH LI) tools to holistically establish knowledge about the current risk posed to the factory. The physical hazards in the factory were assessed in two different operations, which are mixing and filling/packaging. For the risk assessment phase, the hazards were deeply analyzed through their severity and impact. Additionally, through risk mitigation, the Rapid Entire Body Assessment (REBA) score decreased from 11 to 7, and the National Institute for Occupational Safety and Health Lifting Index (NIOSH LI) has been reduced from 5.27 to 1.85.

Keywords: ergonomics, safety, workplace risks, hazards, awkward posture, fatigue, work environment

Procedia PDF Downloads 79

Authors: Athira Babu, M. Nazeer

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Concrete is the most common and versatile construction material used in any type of civil engineering structure. The durability and strength characteristics of concrete make it more desirable among any other construction materials. The manufacture and use of concrete produces wide range of environmental and social consequences. The major component in concrete, cement accounts for roughly 5 % of global CO2 emissions. In order to improve the environmental friendliness of concrete, suitable substitutes are added to concrete. The present study deals with GGBS and silica fume as supplementary cementitious materials. The strength and durability studies were conducted in this ternary blended concrete. Several mixes were adopted with varying percentages of Silica Fume i.e., 5%, 10% and 15%. Binary mix with 50% GGBS was also prepared. GGBS content has been kept constant for the rest of mixes. There is an improvement in compressive strength with addition of Silica Fume.Maximum workability, split tensile strength, modulus of elasticity, flexural strength and impact resistance are obtained for GGBS binary blend. For durability studies, maximum sulphate resistance,carbonation resistance andresistance to chloride ion penetration are obtained for ternary blended concrete. Partial replacement of GGBS and Silica Fume reduces the environmental effects, produces economical and eco-friendly concrete. The study showed that for strength characteristics, binary blended concrete showed better performance while for durability study ternary blend performed better.

Keywords: concrete, GGBS, silica fume, ternary blend

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Authors: Aida Kalantari, Boyang Ji, Tao Chen, Ivan Mijakovic

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3-hydroxypropanoic acid (3-HP) is one of the most important biomass-derivable platform chemicals that can be converted into a number of industrially important compounds. There have been several attempts at production of 3-HP from renewable sources in cell factories, focusing mainly on Escherichia coli, Klebsiella pneumoniae, and Saccharomyces cerevisiae. Despite the significant progress made in this field, commercially exploitable large-scale production of 3-HP in microbial strains has still not been achieved. In this study, we investigated the potential of Bacillus subtilis to be used as a microbial platform for bioconversion of glycerol into 3-HP. Our recombinant B. subtilis strains overexpress the two-step heterologous pathway containing glycerol dehydratase and aldehyde dehydrogenase from various backgrounds. The recombinant strains harboring the codon-optimized synthetic pathway from K. pneumoniae produced low levels of 3-HP. Since the enzymes in the heterologous pathway are sensitive to oxygen, we had to perform our experiments in micro-aerobic conditions. Under these conditions, the cell produces lactate in order to regenerate NAD+, and we found the lactate production to be in competition with the production of 3-HP. Therefore, based on the in silico predictions, we knocked out the glycerol kinase (glpk), which in combination with growth on glucose, resulted in improving the 3-HP titer to 1 g/L and the removal of lactate. Cultivation of the same strain in an enriched medium improved the 3-HP titer up to 7.6 g/L. Our findings provide the first report of successful introduction of the biosynthetic pathway for conversion of glycerol into 3-HP in B. subtilis.

Keywords: bacillus subtilis, glycerol, 3-hydroxypropanoic acid, metabolic engineering

Procedia PDF Downloads 247

Authors: Filip Stojcevski, Tim Hilditch, Luke Henderson

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Although carbon fibre composites are becoming ever more prominent in the engineering industry, interfacial failure still remains one of the most common limitations to material performance. Carbon fiber surface treatments have played a major role in advancing composite properties however research into the influence of manufacturing variables on a fiber manufacturing line is lacking. This project investigates the impact of altering carbon fiber manufacturing conditions on a production line (specifically electrochemical oxidization and sizing variables) to assess fiber-matrix adhesion. Pristine virgin fibers were manufactured and interfacial adhesion systematically assessed from a microscale (single fiber) to a mesoscale (12k tow), and ultimately a macroscale (laminate). Correlations between interfacial shear strength (IFSS) at each level is explored as a function of known interfacial bonding mechanisms; namely mechanical interlocking, chemical adhesion and fiber wetting. Impact of these bonding mechanisms is assessed through extensive mechanical, topological and chemical characterisation. They are correlated to performance as a function of IFSS. Ultimately this study provides a bottoms up approach to improving composite laminates. By understanding the scaling effects from a singular fiber to a composite laminate and linking this knowledge to specific bonding mechanisms, material scientists can make an informed decision on the manufacturing conditions most beneficial for interfacial adhesion.

Keywords: carbon fibers, interfacial adhesion, surface treatment, sizing

Procedia PDF Downloads 265

Authors: H. Ozbasaran

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Lateral torsional buckling is a global stability loss which should be considered in the design of slender structural members under flexure about their strong axis. It is possible to compute the load which causes lateral torsional buckling of a beam by finite element analysis, however, closed form equations are needed in engineering practice. Such equations can be obtained by using energy method. Unfortunately, this method has a vital drawback. In lateral torsional buckling applications of energy method, a proper function for the critical lateral torsional buckling mode should be chosen which can be thought as the variation of twisting angle along the buckled beam. The accuracy of the results depends on how close is the chosen function to the exact mode. Since critical lateral torsional buckling mode of the cantilever I-beams varies due to material properties, section properties, and loading case, the hardest step is to determine a proper mode function. This paper presents an approximate function for critical lateral torsional buckling mode of doubly symmetric cantilever I-beams. Coefficient matrices are calculated for the concentrated load at the free end, uniformly distributed load and constant moment along the beam cases. Critical lateral torsional buckling modes obtained by presented function and exact solutions are compared. It is found that the modes obtained by presented function coincide with differential equation solutions for considered loading cases.

Keywords: buckling mode, cantilever, lateral-torsional buckling, I-beam

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Authors: Raghunandan Gurumurthy, Aricson Pereira, Sandeep Patil

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The escalating adoption of electric vehicles (EVs) across the globe has underscored the critical importance of advancing battery system technologies. This has catalyzed a shift towards the design and development of battery systems that not only exhibit higher energy efficiency but also boast enhanced thermal performance and sophisticated multi-material enclosures. A significant leap in this domain has been the incorporation of simulation-based design optimization for battery packs and Battery Management Systems (BMS), a move further enriched by integrating artificial intelligence/machine learning (AI/ML) approaches. These strategies are pivotal in refining the design, manufacturing, and operational processes for electric vehicles and energy storage systems. By leveraging AI/ML, stakeholders can now predict battery performance metrics—such as State of Health, State of Charge, and State of Power—with unprecedented accuracy. Furthermore, as Li-ion batteries (LIBs) become more prevalent in urban settings, the imperative for bolstering thermal and fire resilience has intensified. This has propelled Battery Thermal Management Systems (BTMs) to the forefront of energy storage research, highlighting the role of machine learning and AI not just as tools for enhanced safety management through accurate temperature forecasts and diagnostics but also as indispensable allies in the early detection and warning of potential battery fires.

Keywords: electric vehicles, battery thermal management, industrial engineering, machine learning, artificial intelligence, manufacturing

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Authors: Krishna Mohan Bathula, Fatou Bintou Loucoubar, FNU Kaleemunnisa, Christelle Scharff, Mark Anthony De Castro

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Voice recognition algorithms such as automatic speech recognition and text-to-speech systems with African languages can play an important role in bridging the digital divide of Artificial Intelligence in Africa, contributing to the establishment of a fully inclusive information society. This paper proposes a Deep Learning model that can classify the user responses as inputs for an interactive voice response system. A dataset with Wolof language words ‘yes’ and ‘no’ is collected as audio recordings. A two stage Data Augmentation approach is adopted for enhancing the dataset size required by the deep neural network. Data preprocessing and feature engineering with Mel-Frequency Cepstral Coefficients are implemented. Convolutional Neural Networks (CNNs) have proven to be very powerful in image classification and are promising for audio processing when sounds are transformed into spectra. For performing voice response classification, the recordings are transformed into sound frequency feature spectra and then applied image classification methodology using a deep CNN model. The inference model of this trained and reusable Wolof voice response recognition system can be integrated with many applications associated with both web and mobile platforms.

Keywords: automatic speech recognition, interactive voice response, voice response recognition, wolof word classification

Procedia PDF Downloads 116

Authors: Nabil Hameed Al-Farsi

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This study’s main goal is to develop a model and a maintenance strategy for a cement factory called Arabian Cement Company, Rabigh Plant. The proposed work here depends on Reliability centric maintenance approach to develop a strategy and maintenance schedule that ensures increasing the reliability of the production system components, thus ensuring continuous productivity. The cost-effective maintenance of the plant’s dependability performance is the key goal of durability-based maintenance is. The cement plant consists of 7 important steps, so, developing a maintenance plan based on Reliability centric maintenance (RCM) method is made up of 10 steps accordingly starting from selecting units and data until performing and updating the model. The processing unit chosen for the analysis of this case is the calcinatory unit regarding model’s validation and the Travancore Titanium Products Ltd (TTP) using the claimed data history acquired from the maintenance department maintenance from the mentioned company. After applying the proposed model, the results of the maintenance simulation justified the plant's existing scheduled maintenance policy being reconsidered. Results represent the need for preventive maintenance for all Class A criticality equipment instead of the planned maintenance and the breakdown one for all other equipment depends on its criticality and an FMEA report. Consequently, the additional cost of preventive maintenance would be offset by the cost savings from breakdown maintenance for the remaining equipment.

Keywords: engineering, reliability, strategy, maintenance, failure modes, effects and criticality analysis (FMEA)

Procedia PDF Downloads 171

Authors: Lauren Provost

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The digital world remains increasingly vulnerable, making the development of effective cybersecurity approaches even more critical in supporting the success of the digital economy and national security. Although approaches to cybersecurity have shifted and improved in the last decade with new models, especially with cloud computing and mobility, a record number of high severity vulnerabilities were recorded in the National Institute of Standards and Technology (NIST), and its National Vulnerability Database (NVD) in 2020. This is due, in part, to the increasing complexity of cyber ecosystems. Security must be approached with a more comprehensive, multi-tool strategy that addresses the complexity of cyber ecosystems, including the human factor. Ethical hacking has emerged as such an approach: a more effective, multi-strategy, comprehensive approach to cyber security's most pressing needs, especially understanding the human factor. Research on ethical hacking, however, is limited in scope. The two main objectives of this work are to (1) provide highlights of case studies in ethical hacking, (2) provide a conceptual framework for research in ethical hacking that embraces and addresses both technical and nontechnical security measures. Recommendations include an improved conceptual framework for research centered on ethical hacking that addresses many factors and attributes of significant attacks that threaten computer security; a more robust, integrative multi-layered framework embracing the complexity of cybersecurity ecosystems.

Keywords: ethical hacking, literature review, penetration testing, social engineering

Procedia PDF Downloads 218

Authors: Shubham Jaiswal

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During modelling of many physical problems and engineering processes, fractional calculus plays an important role. Those are greatly described by fractional differential equations (FDEs). So a reliable and efficient technique to solve such types of FDEs is needed. In this article, a numerical solution of a class of fractional differential equations namely space fractional order reaction-advection dispersion equations subject to initial and boundary conditions is derived. In the proposed approach shifted Jacobi polynomials are used to approximate the solutions together with shifted Jacobi operational matrix of fractional order and spectral collocation method. The main advantage of this approach is that it converts such problems in the systems of algebraic equations which are easier to be solved. The proposed approach is effective to solve the linear as well as non-linear FDEs. To show the reliability, validity and high accuracy of proposed approach, the numerical results of some illustrative examples are reported, which are compared with the existing analytical results already reported in the literature. The error analysis for each case exhibited through graphs and tables confirms the exponential convergence rate of the proposed method.

Keywords: space fractional order linear/nonlinear reaction-advection diffusion equation, shifted Jacobi polynomials, operational matrix, collocation method, Caputo derivative

Procedia PDF Downloads 445

Authors: R. C. Law, Shirley Kang, T. Y. Hin, M. Z. Abdullah

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LED technology has been evolving aggressively in recent years from incandescent bulb during older days to as small as chip scale package. It will continue to stay bright in future. As such, there is tremendous pressure to stay competitive in the market by optimizing products to next level of performance and reliability with the shortest time to market. This changes the conventional way of product design and development to virtual prototyping by means of Computer Aided Engineering (CAE). It comprises of the deployment of Finite Element Method (FEM) and Computational Fluid Dynamic (CFD). FEM accelerates the investigation for early detection of failures such as crack, improve the thermal performance of system and enhance solder joint reliability. CFD helps to simulate the flow pattern of molding material as a function of different temperature, molding parameters settings to evaluate failures like voids and displacement. This paper will briefly discuss the procedures and applications of FEM in thermal stress, solder joint reliability and CFD of compression molding in LED CSP. Integration of virtual prototyping in product development had greatly reduced the time to market. Many successful achievements with minimized number of evaluation iterations required in the scope of material, process setting, and package architecture variant have been materialized with this approach.

Keywords: LED, chip scale packaging (CSP), computational fluid dynamic (CFD), virtual prototyping

Procedia PDF Downloads 287

Authors: Mozhgan Chaichi, Farhad Sharif, Saeede Mazinani

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Polymer nanocomposites are a new class of materials for fabricating future multifunctional and lightweight structures. To obtain good mechanical, thermal and electrical properties, it is essential to achieve uniform dispersion of nanoparticles in polymer matrix. Alignment of nanoparticles in matrix can enhance mechanical, thermal, electrical and barrier properties of nanocomposites in oriented direction. Fe3O4 nanoparticles have generated huge activity in many areas of science and engineering due to its magnetic properties. Magnetic nanoparticles have been investigated for a wide range of applications in sensors, magnetic energy storage, environmental remediation, heterogeneous catalysts and drug delivery. The magnetic response from the Fe3O4 nanoparticles can facilitate with the alignment of nanofillers in a polymer matrix under magnetic field, aiming at fabricating composites with directional properties and functions. Here we report oriented nanocomposites based on Fe3O4 nanoparticles and poly (vinyl alcohol) (PVA), which prepared via a facile aqueous solution by applying a low external magnetic field (750 G). A significant enhancement of mechanical properties, and especially toughness of nanofilms, of oriented PVA/ Fe3O4 nanocomposites is obtained at low nanoparticles loading. Orientation of nanoparticles can align polymer chains and enhance mechanical properties. For example, orientation of 0.1 wt. % Fe3O4 nanoparticles increase 31% toughness and 23% modulus of oriented nanocomposite in compare of pure films, which indicate good dispersion of nanoparticles and efficient load transfer between nanoparticles and matrix.

Keywords: magnetic nanoparticles, nanocomposites, toughness, orientation

Procedia PDF Downloads 329

Authors: Mustafa Yildiz, Ali Sinan Soganci

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Pumice soils are countered in many projects such as transportation roads, channels and residential units throughout the World. The pumice deposits are characterized by the vesicular nature of their particles. When the pumice soils are evaluated considering the geotechnical viewpoint, they differ from silica sands in terms of physical and engineering characteristics. These differences are low grain strength, high friction angle, void ratio and compressibility. At stresses greater than a few hundred kPa, the stress-strain-strength behaviour of these soils is determined by particle crushing. Particle crushing leads to changes in the density and reduction in the components of shear stress due to expansion. In this study, the bearing capacity and behaviour of granular pumice soils compared to sand-gravels were investigated by laboratory model tests. Firstly the geotechnical properties of granular pumice soils were determined; then, the behaviour of pumice soils with an equivalent diameter of sand and gravel soils were investigated by model rectangular and circular foundation types and were compared with each other. For this purpose, basic types of model footing (15*15 cm, 20*20 cm, Φ=15 cm and Φ=20 cm) have been selected. When the experimental results of model bearing capacity are analyzed, the values of sand and gravel bearing capacity tests were found to be 1.0-1.5 times higher than the bearing capacity of pumice the same size. This fact has shown that sand and gravel have a higher bearing capacity than pumice of the similar particle sizes.

Keywords: pumice soils, laboratory model tests, bearing capacity, laboratory model tests, Nevşehir

Procedia PDF Downloads 214

Authors: Zia Ullah, Muhammad Asim, Shi Sujuan, Rayyan Khan, Aaqib Shaheen, LIU Haobao

Abstract:

The plant-specific auxin efflux proteins PIN-FORMED (PIN) have been well depicted in many plant species for their essential roles in regulating the transport of auxins in several phases of plant growth. Little is known about the various functions of the PIN family genes in the Nicotiana tabacum (N. tabacum) species during plant growth. To define the expression pattern of the NtPIN1a gene under abiotic stresses and hormone treatment, transgenic tobacco with promoterNtPIN1a::GUS construct was employed. Comprehensive computational analyses of the NtPIN1a promoter confirmed the existence of common core promoter elements including CAAT-box, TATA-box, hormone, and abiotic stress-responsive elements such as ABRE, P-box, MYC, MYB, ARE, and GC-motifs. The transgenic plants with the promoter of NtPIN1a displayed a promising expression of β-glucuronidase (GUS) in germinating seeds, root tips, shoot-apex, and developing leaves under optimal conditions. While the differential expression of GUS in moderate salt, drought, low potassium stresses, and externally high auxin level at two different time points, suggested NtPIN1a played a key role in growth processes and the plants’ response to abiotic stresses. This analysis provides a foundation for more in-depth discoveries of the biological functions of NtPIN1a in Nicotiana species and this promoter may be employed in genetic engineering of other crops for enhanced stress tolerance.

Keywords: tobacco, nicotiana tabacum, pin, promoter, GUS, abiotic stresses, auxin

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Authors: Biskri Yasmina, Laidi Babouri, Dehas Ouided, Bougherira Nadjiba, Baghloul Rahima

Abstract:

Algeria is one of the countries which have extraordinary resources in vegetable fibers (Palmier, Alfa, Cotton, Sisal). Unfortunately, their valorization in the practical fields, among other things, in building materials, is still little exploited. Several works align with the fact that the use of plant fibers in mortar is an advantageous solution, given its abundance and its socio-economic and environmental impact. The idea of introducing plant fiber into the field of Civil Engineering is not new. Based on the work of several researchers in this field, we propose to study the mechanical behavior of mortar based on Sisal fibers. This work consists of the experimental characterization in the fresh state (workability) and in the hardened state (mechanical resistance to compression and traction by three-point bending) on the scale of mortar mortars based on sisal plant fibers. The main objective of this work is the study of the effect of fiber incorporation on mechanical properties (compressive strength and three-point bending strength). In this study, we varied two parameters, such as the length of the fiber (7cm, 10 cm) and the fibers percentage (0.25%, 0.5%, 0.75%, 1%, 1.25% and 1.5%). The results show that there is a slight increase in the compressive strength of the fiber-reinforced mortars compared to the reference mortar (mortar without fibers). With regard to the three-point bending tests, the fiber-reinforced mortars presented higher resistances compared to the reference mortar and this was for the different lengths and different percentages studied.

Keywords: mortar, plant fiber, experimentation, mechanical characterization, analysis

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Authors: John P. Ulhøi

Abstract:

Firms are faced with pressure to stay innovative and entrepreneurial while at the same time leaving lighter ecological footprints. Traditionally inspiration for new product development (NPD) has come from the creative in-house staff and from the marketplace. Often NPD offered by this approach has proven to be (far from) optimal for its purpose or highly (resource and energy) efficient. More recently, a bio-inspired NPD approach has surfaced under the banner of biomimetics. Biomimetics refers to inspiration from and translations of designs, systems, processes, and or specific properties that exist in nature. The principles and structures working in nature have evolved over a long period of time enable them to be optimized for the purpose and resource and energy-efficient. These characteristics reflect the raison d'être behind the field of biomimetics. While biological expertise is required to understand and explain such natural and biological principles and structures, engineers are needed to translate biological design and processes into synthetic applications. It can, therefore, hardly be surprising, biomimetics long has gained a solid foothold in both biology and engineering. The commercial adoption of biomimetic applications in new production development (NDP) in industry, however, does not quite reflect a similar growth. Differently put, this situation suggests that something is missing in the biomimetic-NPD-equation, thus acting as a brake towards the wider commercial application of biomimetics and thus the use of eco-materials and design in the industry. This paper closes some of that gap. Before concluding, avenues for future research and implications for practice will be briefly sketched out.

Keywords: biomimetics, eco-materials, NPD, commercialization

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Authors: Zahra Alimorad

Abstract:

There is a strong belief that language teachers' actual practices in the classroom context are largely determined by the underlying perceptions they hold about the nature of language and language learning. That being so, it can be envisaged that teaching procedures of ESP (English for Specific Purposes) teachers teaching reading comprehension will mainly be driven by their perceptions about the nature of reading. To examine this issue, four Iranian university professors holding Ph.D. in either TEFL (Teaching English as a Foreign Language) or English Literature who were teaching English to Engineering and Sciences students were recruited to participate in this study. To collect the necessary data, classroom observations and follow-up semi-structured interviews were used. Furthermore, the materials utilized by the teachers such as textbooks, syllabuses, and tests were also examined. Although it can be argued that their perceptions were partially compatible with the established principles, results of the study pointed to a lack of congruence between these teachers' perceptions and their practices, on the one hand, and between the established principles and the practices, on the other. While the literature mostly supports a metacognitive-strategy approach to reading comprehension, the teachers were mainly adopting a skills-based approach to the teaching of reading. That is, they primarily focused on translation as the core activity in the classroom followed by reading aloud, defining words, and explaining grammatical structures. This divergence was partly attributed to the contextual constraints and partly to students' lack of motivation by the teachers.

Keywords: English teachers, perceptions, practice, principles, reading comprehension

Procedia PDF Downloads 262

Authors: Upasana Pattnaik, Akshaya Kumar Sabat

Abstract:

The compaction properties, unconfined compressive strength (UCS), soaked California bearing ratio (CBR), hydraulic conductivity, and swelling pressure of lime stabilized expansive soil-shredded waste tyre mixes have been discussed in this paper. Shredded waste tyres, passing 4.75 mm Indian Standard (IS) sieve and retained on 75µ IS sieve have been used in the experimental programme. First of all expansive soil-shredded waste tyre mixes were prepared by adding shredded waste tyre from 0 to 20% at an increment of 5%.Standard Proctor compaction, UCS and soaked CBR tests were conducted on these mixes. The optimum percentage of shredded waste tyre found out was 10%.In the second phase of the experiment, lime was added to sample having optimum percentage of expansive soil and shredded waste tyre from 2 to 6% at an increment of 1%.Compaction, UCS, soaked CBR, hydraulic conductivity, and swelling pressure tests were conducted on lime stabilized expansive soil-shredded waste tyre mixes. The optimum percentage of lime for stabilization was found out to be 5%.At the optimum percentage of lime the stabilized expansive soil-shredded waste tyre mix had increased strength, reduced hydraulic conductivity and swelling pressure.

Keywords: expansive soil, hydraulic conductivity, lime, shredded waste tyre, soaked california bearing ratio

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Authors: Hamitri-Guerfi Fatiha, Mekimene Lekhder, Madani Khodir, Youyou Ahcene

Abstract:

Virgin olive oil is appreciated by consumers, the quality of the oil is regulated by the international olive oil council depends on its chemical composition, so, the correct packing conditions are a prerequisite to preserve oil color, flavor, and nutriments, from production to consumption. The contact of food with various materials of packaging, since the production, until their consumption constitutes one of the essential aspects of food safety (directive 76/833/CEE). In Algeria, plastic bottles, although, they are economic and light are largely used at packaging olive oil but not used in other countries. This is due to migration phenomena that can occur from these materials. Thus, the goal of this work is to examine the physicochemical behavior of the couple packaging plastic-oil during their exposure to three temperatures corresponding to the conditions of storage applied in Algeria. Like, it is difficult to compare blowers of bottles which are heavy engineering, it comes out from this study that the effect of heat, the absorption of water, the constraints of storage of acidity, as well as the composition of oil, the PET bottles showed a remarkable structural instability, this defect of quality was confirmed by the analysis of morphology by electronic scan microscopy. These bottles present a total migration significantly higher than the threshold of acceptance. Moreover, a metal contamination of oil by its packaging was confirmed by the spectroscopy of atomic absorption and a microanalysis. The differences observed between the results of the microanalysis applied and the mechanical characterizations of the various bottles are reported, showing the reality of the container-contents exchanges.

Keywords: interaction, stability, pet, virgin olive oil

Procedia PDF Downloads 460