Search results for: early age thermal cracking
3088 Characterization and Comparative Analysis of North Bengal Sand
Authors: Marzia Hoque Tania, Oishy Roy, ASW Kurny, Fahmida Gulshan
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This paper presents results of the investigation on the characterization of silica sand of northern region of Bangladesh on the basis of material composition, particle shape, and size, density, transportation, crystallinity, etc. before and after upgradation. The raw sand samples collected from Nilphamari and Lalmonirhat district were studied and compared for the prospect silica as a high valued commodity rather than heavy minerals. The raw sand particles were colorful in appearance with varying particle size distribution. Scanning Electron Microscopy (SEM) showed uniformity in grain size and mineralogical composition. X-ray fluorescence (XRF) analysis indicated the silica content of the as-received sample to be 75%. Thermogravimetric and Differential Thermal Analysis (DTA) did not detect the presence of any organic material. These tests revealed the sample to be alpha-quartz. Samples were washed with organic and inorganic acid with a combination of varying rotation speed, concentration, solid-liquid ratio. Experiments showed the silica content could be enhanced to more than 85% by washing with 15% sulphuric acid in room temperature. Beneficiation can be improved in further work considering the effect of varying temperature or advanced technology.Keywords: beneficiation, characterization, commercial grade sand, glass sand, silica, upgradation
Procedia PDF Downloads 1393087 Thermal Pre-Treatment of Sewage Sludge in Fluidized Bed for Enhancing Its Solid Fuel Properties
Authors: Sujeeta Karki, Jeeban Poudel, Ja Hyung Choi, Sea Cheon Oh
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A lab-scale fluidized bed was used for the study of sewage sludge, a non-lignocellulosic biomass, torrefaction. The influence of torrefaction temperature ranging from 200–350 °C and residence time of 0–50 minutes on the physical and chemical properties of the torrefied product was investigated. Properties of the torrefied product were analyzed on the basis of degree of torrefaction, ultimate and proximate analysis, gas analysis and chemical exergy. The degree of torrefaction and chemical exergy had a positive influence on increasing the torrefaction temperature. Moreover, the effect of torrefaction temperature and residence time on the elemental variation of sewage sludge exhibited an increase in the weight percentage of carbon while the content of H/C and O/C molar ratios decreased. The product gas emitted during torrefaction was analyzed to study the pathway of hydrocarbons and oxygen-containing compounds. The compounds with oxygen were emitted at higher temperatures in contrast to hydrocarbon gases. An attempt was made to obtain the chemical exergy of sewage sludge. In addition, the study of various correlations for predicting the calorific value of torrefied sewage sludge was made.Keywords: chemical exergy, degree of torrefaction, fluidized bed, higher heating value (HHV), O/C and H/C molar ratios, sewage sludge
Procedia PDF Downloads 1703086 Interaction with Earth’s Surface in Remote Sensing
Authors: Spoorthi Sripad
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Remote sensing is a powerful tool for acquiring information about the Earth's surface without direct contact, relying on the interaction of electromagnetic radiation with various materials and features. This paper explores the fundamental principle of "Interaction with Earth's Surface" in remote sensing, shedding light on the intricate processes that occur when electromagnetic waves encounter different surfaces. The absorption, reflection, and transmission of radiation generate distinct spectral signatures, allowing for the identification and classification of surface materials. The paper delves into the significance of the visible, infrared, and thermal infrared regions of the electromagnetic spectrum, highlighting how their unique interactions contribute to a wealth of applications, from land cover classification to environmental monitoring. The discussion encompasses the types of sensors and platforms used to capture these interactions, including multispectral and hyperspectral imaging systems. By examining real-world applications, such as land cover classification and environmental monitoring, the paper underscores the critical role of understanding the interaction with the Earth's surface for accurate and meaningful interpretation of remote sensing data.Keywords: remote sensing, earth's surface interaction, electromagnetic radiation, spectral signatures, land cover classification, archeology and cultural heritage preservation
Procedia PDF Downloads 633085 Separation Performance of CO₂ by Mixed Matrix Membrane Comprising Carbide-Derived Carbon
Authors: Musa Najimu, Isam Aljundi
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In this study, the development of mixed matrix membrane (MMM) containing carbide-derived carbon (CDC) for the separation of CO₂ was investigated. MMM with four different loadings (0.1 to 2 wt%) were prepared by the dry/wet phase inversion technique. Prior to this, the formula of the control polysulfone (PSF) membrane was optimized in terms of the PSF concentration in a mixture of NMP/THF solvents and ethanol. Prepared samples were characterized and tested for CO₂ and CH₄ gas permeation. The optimization of the control PSF membrane revealed that 30 wt% PSF is the critical polymer concentration in the formulation. Characterization results unveiled reinforcement of thermal stability and improved polarity imparted by CDC in the MMM, in addition to uniform dispersion of filler up to 1 wt% loading. Furthermore, the incorporation of CDC in PSF membrane formulation enhanced both the CO₂ permeance and ideal selectivity over the control membrane. A CDC loading of 0.5 wt% resulted in the highest CO₂ permeance of 5.5 GPU corresponding to 120% increase in permeance while a CDC loading of 1 wt% resulted in the highest selectivity (CO₂ /CH₄) of 27 corresponding to 29% increase in selectivity. Studies of operating temperature effect showed that an optimum operating temperature for M1.0 membrane is 20 ⁰C. In addition, the feed pressure studies showed that high pressure feeds will favor high performance of the membrane and a good CO₂ /CH₄ separation.Keywords: carbide derived carbon, mixed matrix membrane, CO₂ separation, polysulfone
Procedia PDF Downloads 2103084 Storytelling as a Pedagogical Tool to Learn English Language in Higher Education: Using Reflection and Experience to Improve Learning
Authors: Barzan Hadi Hama Karim
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The purpose of this research study is to determine how educators, students at the university level are using storytelling to support the educational process. This study provides a general framework about educational uses of storytelling as a pedagogical too to learn English language in the higher education and describes the different perceptions of people (teachers and students) at different levels. A survey is used to collect responses from a group of educators and students in educational settings to determine how they are using storytelling for educational purposes. The results show the current situation of educational uses of storytelling and explore some of the benefits and challenges educators face in implementing storytelling in their institutions. The purpose of our research is to investigate the impact of storytelling as a pedagogical tool to learn English language in higher education and its academic achievements on ESL students. It highlights findings that address the following questions: (1) How has storytelling been approached historically? (2) Is storytelling beneficial for students in early grades at university? (3) To what extent do teacher and student prefer storytelling as a pedagogical tool to teach and learn English language in higher education?Keywords: storytelling, teacher's beliefs, student’s beliefs, student’s academic achievement, narrative, pedagogy, ESL
Procedia PDF Downloads 3963083 Conductometric Methanol Microsensor Based on Electrospun PVC-Nickel Phthalocyanine Composite Nanofiber Technology
Authors: Ibrahim Musa, Guy Raffin, Marie Hangouet, Nadia Zine, Nicole Jaffrezic-Renault, Abdelhamid Errachid
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Due to its application in different domains, such as fuel cell configuration and adulteration of alcoholic beverages, a miniaturized sensor for methanol detection is urgently required. A conductometric microsensor for measuring volatile organic compounds (VOC) was conceived, based on electrospun composite nanofibers of polyvinyl chloride (PVC) doped with nickel phthalocyanine(NiPc) deposited on interdigitated electrodes (IDEs) used transducers. The nanofiber's shape, structure, percent atomic content and thermal properties were studied using analytical techniques, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), respectively. The methanol sensor showed good sensitivity (505µS/cm(v/v) ⁻¹), low LOD (15 ppm), short response time (13 s), and short recovery time (15 s). The sensor was 4 times more sensitive to methanol than to ethanol and 19 times more sensitive to methanol than to acetone. Furthermore, the sensor response was unaffected by the interfering water vapor, making it more suitable for VOC sensing in the presence of humidity. The sensor was applied for conductometric detection of methanol in rubbing alcohol.Keywords: composite, methanol, conductometric sensor, electrospun, nanofiber, nickel phthalocyanine, PVC
Procedia PDF Downloads 323082 Thermodynamic Modeling of Three Pressure Level Reheat HRSG, Parametric Analysis and Optimization Using PSO
Authors: Mahmoud Nadir, Adel Ghenaiet
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The main purpose of this study is the thermodynamic modeling, the parametric analysis, and the optimization of three pressure level reheat HRSG (Heat Recovery Steam Generator) using PSO method (Particle Swarm Optimization). In this paper, a parametric analysis followed by a thermodynamic optimization is presented. The chosen objective function is the specific work of the steam cycle that may be, in the case of combined cycle (CC), a good criterion of thermodynamic performance analysis, contrary to the conventional steam turbines in which the thermal efficiency could be also an important criterion. The technologic constraints such as maximal steam cycle temperature, minimal steam fraction at steam turbine outlet, maximal steam pressure, minimal stack temperature, minimal pinch point, and maximal superheater effectiveness are also considered. The parametric analyses permitted to understand the effect of design parameters and the constraints on steam cycle specific work variation. PSO algorithm was used successfully in HRSG optimization, knowing that the achieved results are in accordance with those of the previous studies in which genetic algorithms were used. Moreover, this method is easy to implement comparing with the other methods.Keywords: combined cycle, HRSG thermodynamic modeling, optimization, PSO, steam cycle specific work
Procedia PDF Downloads 3853081 The Mediatization of Political Communication in Sub-Saharan Africa: The Cases of Cameroon and Ghana in a Comparative Perspective
Authors: Christian Nounkeu Tatchou
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The concept of mediatization of politics describes changes with regards to media and politics, as the political sphere is increasingly shaped by the media and conforms to its logic. The mediatization of politics in established democracies of the West has been the object of several researches. However, there is an overwhelming paucity of literature on this reconfiguration of the political life around the media in the emerging democracies of the Sub-Saharan Africa. A majority of Sub-Saharan countries have been progressively experiencing the modernization of their societies and significant developments with respect to political communication since the early 1990s. This has been facilitated by factors such as the adoption of democratic reforms, the development of mass media, the advent of social media and the rapid spread of new information and communication technologies. Thus, this paper investigates the extent to which political communication in Sub-Saharan Africa is mediatized, especially with regards to the social media. Through in-depths interviews with twenty political leaders and political observers in Cameroon and Ghana, this article argues that the social media has become the main arena of voters’ mobilization and political participation in Sub-Saharan Africa. However, a greater extent of freedom for political activism on social media is observed in the new democracy of Ghana, unlike in the enduring authoritarian political system of Cameroon where the government attempts to control the use and content of political discourse on social media.Keywords: mediatization, political communication, social media, sub-saharan africa
Procedia PDF Downloads 3573080 Minimizing Students' Learning Difficulties in Mathematics
Authors: Hari Sharan Pandit
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Mathematics teaching in Nepal has been centralized and guided by the notion of transfer of knowledge and skills from teachers to students. The overemphasis on the ‘algorithm-centric’ approach to mathematics teaching and the focus on ‘role–learning’ as the ultimate way of solving mathematical problems since the early years of schooling have been creating severe problems in school-level mathematics in Nepal. In this context, the author argues that students should learn real-world mathematical problems through various interesting, creative and collaborative, as well as artistic and alternative ways of knowing. The collaboration-incorporated pedagogy is a distinct pedagogical approach that offers a better alternative as an integrated and interdisciplinary approach to learning that encourages students to think more broadly and critically about real-world problems. The paper, as a summarized report of action research designed, developed and implemented by the author, focuses on the needs and usefulness of collaboration-incorporated pedagogy in the Nepali context to make mathematics teaching more meaningful for producing creative and critical citizens. This paper is useful for mathematics teachers, teacher educators and researchers who argue on arts integration in mathematics teaching.Keywords: peer teaching, metacognitive approach, mitigating, action research
Procedia PDF Downloads 323079 The Value of Online News: Addressing the Problem of Online Investment Fraud Crimes in Thailand
Authors: Thapthep Paprach, Benya Lertsuwan
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Investment fraud is not a new criminal, but there are still more victims during the Internet of Things era. This kind of criminal has been classified as a national and transnational financial crime problem all over the world. In Thailand, the country has also been attacked by this kind of crime. This research concerns whether the mass media that is supposed to cover news about online investment scams realized and warned Thais about this crime. Thus, this study explores the value of news about investment fraud in terms of frequency. The methodology uses web crawling from the top 5 news agency websites that have the most access. We pull out all information reporting about investment fraud. The findings revealed that the ‘Khaosod’ news agency was the first rank in reporting on investment crime. On the other hand, ‘Matichon’ was the least reported. Thairat news agencies frequently reported such criminals from midnight to very early in the morning, while other news agencies reported during the daytime. The results between the frequency of news reporting about investment fraud and the monthly number of victim reports are not correlated. Although the most cases reported to Thai police were in February 2023, but the most news reported was in January 2023. In conclusion, there might be a negative correlation between the amount of investment fraud news reported and the number of victims.Keywords: investment fraud, news value, online news report, Ponzi schemes, Romance scam
Procedia PDF Downloads 823078 Impact of Legs Geometry on the Efficiency of Thermoelectric Devices
Authors: Angel Fabian Mijangos, Jaime Alvarez Quintana
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Key concepts like waste heat recycling or waste heat recovery are the basic ideas in thermoelectricity so as to the design the newest solid state sources of energy for a stable supply of electricity and environmental protection. According to several theoretical predictions; at device level, the geometry and configuration of the thermoelectric legs are crucial in the thermoelectric performance of the thermoelectric modules. Thus, in this work, it has studied the geometry effect of legs on the thermoelectric figure of merit ZT of the device. First, asymmetrical legs are proposed in order to reduce the overall thermal conductance of the device so as to increase the temperature gradient in the legs, as well as by harnessing the Thomson effect, which is generally neglected in conventional symmetrical thermoelectric legs. It has been developed a novel design of a thermoelectric module having asymmetrical legs, and by first time it has been validated experimentally its thermoelectric performance by realizing a proof-of-concept device which shows to have almost twofold the thermoelectric figure of merit as compared to conventional one. Moreover, it has been also varied the length of thermoelectric legs in order to analyze its effect on the thermoelectric performance of the device. Along with this, it has studied the impact of contact resistance in these systems. Experimental results show that device architecture can improve up to twofold the thermoelectric performance of the device.Keywords: asymmetrical legs, heat recovery, heat recycling, thermoelectric module, Thompson effect
Procedia PDF Downloads 2463077 Structural Health Monitoring and Damage Structural Identification Using Dynamic Response
Authors: Reza Behboodian
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Monitoring the structural health and diagnosing their damage in the early stages has always been one of the topics of concern. Nowadays, research on structural damage detection methods based on vibration analysis is very extensive. Moreover, these methods can be used as methods of permanent and timely inspection of structures and prevent further damage to structures. Non-destructive methods are the low-cost and economical methods for determining the damage of structures. In this research, a non-destructive method for detecting and identifying the failure location in structures based on dynamic responses resulting from time history analysis is proposed. When the structure is damaged due to the reduction of stiffness, and due to the applied loads, the displacements in different parts of the structure were increased. In the proposed method, the damage position is determined based on the calculation of the strain energy difference in each member of the damaged structure and the healthy structure at any time. Defective members of the structure are indicated by the amount of strain energy relative to the healthy state. The results indicated that the proper accuracy and performance of the proposed method for identifying failure in structures.Keywords: failure, time history analysis, dynamic response, strain energy
Procedia PDF Downloads 1393076 Influence of Metakaolin and Cements Types on Compressive Strength and Transport Properties of Self-Consolidating Concrete
Authors: Kianoosh Samimi, Farhad Estakhr, Mahdi Mahdikhani, Faramaz Moodi
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The self-consolidating concrete (SCC) performance over ordinary concrete is generally related to the ingredients used. The metakaolin can modify various properties of concrete, due to high pozzolanic reactions and also makes a denser microstructure. The objective of this paper is to examine the influence of three types of Portland cement and metakaolin on compressive strength and transport properties of SCC at early ages and up to 90 days. Six concrete mixtures were prepared with three types of different cements and substitution of 15% metakaolin. The results show that the highest value of compressive strength was achieved for Portland Slag Cement (PSC) and without any metakaolin at age of 90 days. Conversely, the lowest level of compressive strength at all ages of conservation was obtained for Pozzolanic Portland Cement (PPC) and containing 15% metakaolin. As can be seen in the results, compressive strength in SCC containing Portland cement type II with metakaolin is higher compared to that relative to SCC without metakaolin from 28 days of age. On the other hand, the samples containing PSC and PPC with metakaolin had a lower compressive strength than the plain samples. Therefore, it can be concluded that metakaolin has a negative effect on the compressive strength of SCC containing PSC and PPC. In addition, results show that metakaolin has enhanced chloride durability of SCCs and reduced capillary water absorption at 28, 90 days.Keywords: SCC, metakaolin, cement type, compressive strength, chloride diffusion
Procedia PDF Downloads 2253075 Cellulose Acetate/Polyacrylic Acid Filled with Nano-Hydroxapatite Composites: Spectroscopic Studies and Search for Biomedical Applications
Authors: E. M. AbdelRazek, G. S. ElBahy, M. A. Allam, A. M. Abdelghany, A. M. Hezma
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Polymeric biocomposite of hydroxyapatite/polyacrylic acid were prepared and their thermal and mechanical properties were improved by addition of cellulose acetate. FTIR spectroscopy technique and X-ray diffraction analysis were employed to examine the physical and chemical characteristics of the biocomposites. Scanning electron microscopy shows a uniform distribution of HAp nano-particles through the polymeric matrix of two organic/inorganic composites weight ratios (60/40 and 70/30), at which the material crystallinity reaches a considerable value appropriate for the needed applications were studied and revealed that the HAp nano-particles are uniformly distributed in the polymeric matrix. Kinetic parameters were determined from the weight loss data using non isothermal thermogravimetric analysis (TGA). Also, the main degradation steps were described and discussed. The mechanical properties of composites were evaluated by measuring tensile strength and elastic modulus. The data indicate that the addition of cellulose acetate can make homogeneous composites scaffold significantly resistant to higher stress. Elastic modulus of the composites was also improved by the addition of cellulose acetate, making them more appropriate for bioapplications.Keywords: biocomposite, chemical synthesis, infrared spectroscopy, mechanical properties
Procedia PDF Downloads 4613074 Flo: Period-Tracking App with AI Powered Tools
Authors: Dania Baaboud, Renad Al-zahrani, Mahnoor Khan, Riya Afroz
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Flo is a smart period-tracking tool that uses artificial intelligence (AI) to offer individualized reproductive health predictions and insights. Flo makes very accurate predictions about menstrual cycles, ovulation, and fertility windows by evaluating user inputs, including cycle duration, symptoms, and patterns. Its machine learning algorithms are constantly evolving, providing personalized health recommendations, instructional materials, and early identification of possible health abnormalities such as reproductive problems and hormone imbalances. Flo, which was introduced in 2015 and upgraded with AI in 2017, is a revolutionary use of technology in healthcare that empowers people to make knowledgeable decisions regarding their well-being. Despite its advantages, our study included drawbacks, such as limited access to premium services and a small sample size. While highlighting unique characteristics, a comparative comparison with similar applications such as Clue and Glow confirmed Flo's outstanding AI integration for individualized healthcare. All things considered, Flo is a prime example of how AI can be used to tackle intricate biological processes, giving consumers the ability to efficiently control their reproductive health and opening the door for improvements in individualized medical technology.Keywords: Flo, period-tracking app, period symptoms, women’s health, machinery
Procedia PDF Downloads 103073 The Beam Expansion Method, A Simplified and Efficient Approach of Field Propagation and Resonators Modes Study
Authors: Zaia Derrar Kaddour
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The study of a beam throughout an optical path is generally achieved by means of diffraction integral. Unfortunately, in some problems, this tool turns out to be not very friendly and hard to implement. Instead, the beam expansion method for computing field profiles appears to be an interesting alternative. The beam expansion method consists of expanding the field pattern as a series expansion in a set of orthogonal functions. Propagating each individual component through a circuit and adding up the derived elements leads easily to the result. The problem is then reduced to finding how the expansion coefficients change in a circuit. The beam expansion method requires a systematic study of each type of optical element that can be met in the considered optical path. In this work, we analyze the following fundamental elements: first order optical systems, hard apertures and waveguides. We show that the former element type is completely defined thanks to the Gouy phase shift expression we provide and the latters require a suitable mode conversion. For endorsing the usefulness and relevance of the beam expansion approach, we show here some of its applications such as the treatment of the thermal lens effect and the study of unstable resonators.Keywords: gouy phase shift, modes, optical resonators, unstable resonators
Procedia PDF Downloads 663072 Physical Properties and Elastic Studies of Fluoroaluminate Glasses Based on Alkali
Authors: C. Benhamideche
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Fluoroaluminate glasses have been reported as the earliest heavy metal fluoride glasses. By comparison with flurozirconate glasses, they offer a set of similar optical features, but also some differences in their elastic and chemical properties. In practice they have been less developed because their stability against devitrification is smaller than that of the most stable fluoroziconates. The purpose of this study was to investigate glass formation in systems AlF3-YF3-PbF2-MgF2-MF2 (M= Li, Na, K). Synthesis was implemented at room atmosphere using the ammonium fluoride processing. After fining, the liquid was into a preheated brass mold, then annealed below the glass transition temperature for several hours. The samples were polished for optical measurements. Glass formation has been investigated in a systematic way, using pseudo ternary systems in order to allow parameters to vary at the same time. We have chosen the most stable glass compositions for the determination of the physical properties. These properties including characteristic temperatures, density and proprieties elastic. Glass stability increases in multicomponent glasses. Bulk samples have been prepared for physical characterization. These glasses have a potential interest for passive optical fibers because they are less sensitive to water attack than ZBLAN glass, mechanically stronger. It is expected they could have a larger damage threshold for laser power transmission.Keywords: fluoride glass, aluminium fluoride, thermal properties, density, proprieties elastic
Procedia PDF Downloads 2443071 A Multi-Criteria Decision Making (MCDM) Approach for Assessing the Sustainability Index of Building Façades
Authors: Golshid Gilani, Albert De La Fuente, Ana Blanco
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Sustainability assessment of new and existing buildings has generated a growing interest due to the evident environmental, social and economic impacts during their construction and service life. Façades, as one of the most important exterior elements of a building, may contribute to the building sustainability by reducing the amount of energy consumption and providing thermal comfort for the inhabitants, thus minimizing the environmental impact on both the building and on the environment. Various methods have been used for the sustainability assessment of buildings due to the importance of this issue. However, most of the existing methods mainly concentrate on environmental and economic aspects, disregarding the third pillar of sustainability, which is the social aspect. Besides, there is a little focus on comprehensive sustainability assessment of facades, as an important element of a building. This confirms the need of developing methods for assessing the sustainable performance of building façades as an important step in achieving building sustainability. In this respect, this paper aims at presenting a model for assessing the global sustainability of façade systems. for that purpose, the Integrated Value Model for Sustainable Assessment (MIVES), a Multi-Criteria Decision Making model that integrates the main sustainability requirements (economic, environmental and social) and includes the concept of value functions, used as an assessment tool.Keywords: façade, MCDM, MIVES, sustainability
Procedia PDF Downloads 3493070 Pre-Service Science Teachers’ Attitudes about Teaching Science Courses at the Faculty of Education, Lebanese University: An Exploratory Case Study
Authors: Suzanne El Takach
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The research study explored pre-service teachers’ attitudes towards 6 courses taught in 3rd till 6th semesters at the Faculty of Education, Lebanese University, during the academic year 2015-2016. They assessed science teaching courses that are essential for teacher preparation for Science at the primary and elementary level. These courses were: Action Research I and II in Teaching Science, New trends in Teaching Science, Teaching Science I and II for the elementary level and Teaching Science for Early Childhood Education. Qualitative and Quantitative Data were gathered from a) a survey questionnaire consisting of 23 closed-ended items; some were of Likert scale type, that aimed at collecting students’ opinions on courses, in terms of teaching, assessment and class interaction (N=102 respondents) and b) a second questionnaire of 10 questions was disseminated on a sample of 39 students in their last semester in science and Mathematics, in order to know more about students’ skills gained, suggestions for new courses and improvement. Students were satisfied with science teaching courses and they have admitted that they gained a good pedagogical content knowledge, such as, lesson planning, students’ misconceptions, and use of various teaching and assessment strategies.Keywords: assessment in higher education, LMD program, pre-service teachers’ attitudes, pre-PCK skills
Procedia PDF Downloads 1513069 Numerical Investigation of Hot Oil Velocity Effect on Force Heat Convection and Impact of Wind Velocity on Convection Heat Transfer in Receiver Tube of Parabolic Trough Collector System
Authors: O. Afshar
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A solar receiver is designed for operation under extremely uneven heat flux distribution, cyclic weather, and cloud transient cycle conditions, which can include large thermal stress and even receiver failure. In this study, the effect of different oil velocity on convection coefficient factor and impact of wind velocity on local Nusselt number by Finite Volume Method will be analyzed. This study is organized to give an overview of the numerical modeling using a MATLAB software, as an accurate, time efficient and economical way of analyzing the heat transfer trends over stationary receiver tube for different Reynolds number. The results reveal when oil velocity is below 0.33m/s, the value of convection coefficient is negligible at low temperature. The numerical graphs indicate that when oil velocity increases up to 1.2 m/s, heat convection coefficient increases significantly. In fact, a reduction in oil velocity causes a reduction in heat conduction through the glass envelope. In addition, the different local Nusselt number is reduced when the wind blows toward the concave side of the collector and it has a significant effect on heat losses reduction through the glass envelope.Keywords: receiver tube, heat convection, heat conduction, Nusselt number
Procedia PDF Downloads 3603068 Critical Evaluation of Groundwater Monitoring Networks for Machine Learning Applications
Authors: Pedro Martinez-Santos, Víctor Gómez-Escalonilla, Silvia Díaz-Alcaide, Esperanza Montero, Miguel Martín-Loeches
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Groundwater monitoring networks are critical in evaluating the vulnerability of groundwater resources to depletion and contamination, both in space and time. Groundwater monitoring networks typically grow over decades, often in organic fashion, with relatively little overall planning. The groundwater monitoring networks in the Madrid area, Spain, were reviewed for the purpose of identifying gaps and opportunities for improvement. Spatial analysis reveals the presence of various monitoring networks belonging to different institutions, with several hundred observation wells in an area of approximately 4000 km2. This represents several thousand individual data entries, some going back to the early 1970s. Major issues included overlap between the networks, unknown screen depth/vertical distribution for many observation boreholes, uneven time series, uneven monitored species, and potentially suboptimal locations. Results also reveal there is sufficient information to carry out a spatial and temporal analysis of groundwater vulnerability based on machine learning applications. These can contribute to improve the overall planning of monitoring networks’ expansion into the future.Keywords: groundwater monitoring, observation networks, machine learning, madrid
Procedia PDF Downloads 823067 The Impact of Artificial Intelligence on Textiles Technology
Authors: Ramy Kamel Fekrey Gadelrab
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Textile sensors have gained a lot of interest in recent years as it is instrumental in monitoring physiological and environmental changes, for a better diagnosis that can be useful in various fields like medical textiles, sports textiles, protective textiles, agro textiles, and geo-textiles. Moreover, with the development of flexible textile-based wearable sensors, the functionality of smart clothing is augmented for a more improved user experience when it comes to technical textiles. In this context, conductive textiles using new composites and nanomaterials are being developed while considering its compatibility with the textile manufacturing processes. This review aims to provide a comprehensive and detailed overview of the contemporary advancements in textile-based wearable physical sensors, used in the field of medical, security, surveillance, and protection, from a global perspective. The methodology used is through analysing various examples of integration of wearable textile-based sensors with clothing for daily use, keeping in mind the technological advances in the same. By comparing various case studies, it come across various challenges textile sensors, in terms of stability, the comfort of movement, and reliable sensing components to enable accurate measurements, in spite of progress in the engineering of the wearable. Addressing such concerns is critical for the future success of wearable sensors.Keywords: nanoparticles, enzymes, immobilization, textilesconductive yarn, e-textiles, smart textiles, thermal analysisflexible textile-based wearable sensors, contemporary advancements, conductive textiles, body conformal design
Procedia PDF Downloads 533066 SPR Immunosensor for the Detection of Staphylococcus aureus
Authors: Muhammad Ali Syed, Arshad Saleem Bhatti, Chen-zhong Li, Habib Ali Bokhari
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Surface plasmon resonance (SPR) biosensors have emerged as a promising technique for bioanalysis as well as microbial detection and identification. Real time, sensitive, cost effective, and label free detection of biomolecules from complex samples is required for early and accurate diagnosis of infectious diseases. Like many other types of optical techniques, SPR biosensors may also be successfully utilized for microbial detection for accurate, point of care, and rapid results. In the present study, we have utilized a commercially available automated SPR biosensor of BI company to study the microbial detection form water samples spiked with different concentration of Staphylococcus aureus bacterial cells. The gold thin film sensor surface was functionalized to react with proteins such as protein G, which was used for directed immobilization of monoclonal antibodies against Staphylococcus aureus. The results of our work reveal that this immunosensor can be used to detect very small number of bacterial cells with higher sensitivity and specificity. In our case 10^3 cells/ml of water have been successfully detected. Therefore, it may be concluded that this technique has a strong potential to be used in microbial detection and identification.Keywords: surface plasmon resonance (SPR), Staphylococcus aureus, biosensors, microbial detection
Procedia PDF Downloads 4773065 End-to-End Pyramid Based Method for Magnetic Resonance Imaging Reconstruction
Authors: Omer Cahana, Ofer Levi, Maya Herman
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Magnetic Resonance Imaging (MRI) is a lengthy medical scan that stems from a long acquisition time. Its length is mainly due to the traditional sampling theorem, which defines a lower boundary for sampling. However, it is still possible to accelerate the scan by using a different approach such as Compress Sensing (CS) or Parallel Imaging (PI). These two complementary methods can be combined to achieve a faster scan with high-fidelity imaging. To achieve that, two conditions must be satisfied: i) the signal must be sparse under a known transform domain, and ii) the sampling method must be incoherent. In addition, a nonlinear reconstruction algorithm must be applied to recover the signal. While the rapid advances in Deep Learning (DL) have had tremendous successes in various computer vision tasks, the field of MRI reconstruction is still in its early stages. In this paper, we present an end-to-end method for MRI reconstruction from k-space to image. Our method contains two parts. The first is sensitivity map estimation (SME), which is a small yet effective network that can easily be extended to a variable number of coils. The second is reconstruction, which is a top-down architecture with lateral connections developed for building high-level refinement at all scales. Our method holds the state-of-art fastMRI benchmark, which is the largest, most diverse benchmark for MRI reconstruction.Keywords: magnetic resonance imaging, image reconstruction, pyramid network, deep learning
Procedia PDF Downloads 963064 Statistical Manufacturing Cell/Process Qualification Sample Size Optimization
Authors: Angad Arora
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In production operations/manufacturing, a cell or line is typically a bunch of similar machines (computer numerical control (CNCs), advanced cutting, 3D printing or special purpose machines. For qualifying a typical manufacturing line /cell / new process, Ideally, we need a sample of parts that can be flown through the process and then we make a judgment on the health of the line/cell. However, with huge volumes and mass production scope, such as in the mobile phone industry, for example, the actual cells or lines can go in thousands and to qualify each one of them with statistical confidence means utilizing samples that are very large and eventually add to product /manufacturing cost + huge waste if the parts are not intended to be customer shipped. To solve this, we come up with 2 steps statistical approach. We start with a small sample size and then objectively evaluate whether the process needs additional samples or not. For example, if a process is producing bad parts and we saw those samples early, then there is a high chance that the process will not meet the desired yield and there is no point in keeping adding more samples. We used this hypothesis and came up with 2 steps binomial testing approach. Further, we also prove through results that we can achieve an 18-25% reduction in samples while keeping the same statistical confidence.Keywords: statistics, data science, manufacturing process qualification, production planning
Procedia PDF Downloads 1023063 Preparation and Characterization of the TiO₂ Photocatalytic Membrane for the Degradation of Reactive Orange 16 Dye
Authors: Shruti Sakarkar, Jega Jegatheesan, Srinivasan Madapusi
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Photocatalytic membranes have shown great potential for the removal of an organic and inorganic pollutant from wastewater as it combines the degradation and antibacterial properties from photocatalysis and physical separation by the membrane in a single unit. Incorporation of the semiconductor in membrane structure results in enhancing the performance and the properties of the membrane. In this study porous ultrafiltration polyvinylidene fluoride (PVDF) membranes with entrapped TiO₂ nanoparticle were prepared by phase inversion method and further used for the degradation of reactive orange 16 (RO16). Prepared photocatalytic membranes were characterized by the scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), contact angle, and atomic force microscope (AFM). The addition of TiO₂ nanopartparticles improves the strength and thermal stability of the membrane. In particular hydrophilicity and permeability increases with the increase of TiO₂ nanoparticles into the membrane. The photocatalytic membrane achieves 80-85% degrdation of RO16. The impact of different parameters such as pH, concentration of photocatalyst, dye concentration and effect of H₂O₂ were analysed. The best conditions for dye degradation were an initial dye concentration of 50 mg/L, with a membrane containing TiO₂ loading of 2wt%. It was observed that in the presence of H₂O₂, degradation increases with increasing H₂O₂ concentration and reached up to 95-98%. The high quality permeates obtained from the photocatalytic membrane can be reused.Keywords: photocatalytic membrane, TiO₂, PVDF, nanoparticles
Procedia PDF Downloads 1703062 Antifungal Nature of Bacillus Subtilis in Controlling Post Harvest Fungal Rot of Yam
Authors: Ifueko Oghogho Ukponmwan, Mike O. Orji
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This study investigated the antifungal activity of Bacilluss subtilis in the control of postharvest fungal rot of white yam (Dioscorea spp). Bacillus subtilis was isolated from the soil and fungi (Aspergillus spp, Mucor and yeasts) were isolated from rotten yam. The organisms were paired in yam nutrient agar (YNA) and yam Sabourraud dextrose agar media. In the yam dextrose agar media (YSDA) plates, the Bacillus grew rapidly and established itself and restricted the growth of the fungi organisms, but there was no zone of inhibition. This behaviour of Bacillus on the plates of YSDA was also observed in the yams where the fungi caused rot but the rot was suppressed by the presence of the Bacillus as compared to the degree of rot observed in the control that had only spoilage fungi. The control yam showed greater rot than other yams that contained a combination of Bacillus and fungi. The t-Test analysis showed that the difference in the rot between the treated samples and the control sample is significant and this implies that the presence of Bacillus significantly reduced the growth of fungi in the samples (yams). It was revealed from this study that Bacillus subtilis treatment can be successfully used to preserve white yams in storage. Its fast growth and early establishment in the sample accounts for its antifungal strength.Keywords: Bacillus subtilis, rot, fungi, yam
Procedia PDF Downloads 1873061 Economic Analysis of Domestic Combined Heat and Power System in the UK
Authors: Thamo Sutharssan, Diogo Montalvao, Wen-Chung Wang, Yong Chen, Claudia Pisac
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A combined heat and power (CHP) system is an efficient and clean way to generate power (electricity). Heat produced by the CHP system can be used for water and space heating. The CHP system which uses hydrogen as fuel produces zero carbon emission. Its’ efficiency can reach more than 80% whereas that of a traditional power station can only reach up to 50% because much of the thermal energy is wasted. The other advantages of CHP systems include that they can decentralize energy generation, improve energy security and sustainability, and significantly reduce the energy cost to the users. This paper presents the economic benefits of using a CHP system in the domestic environment. For this analysis, natural gas is considered as potential fuel as the hydrogen fuel cell based CHP systems are rarely used. UK government incentives for CHP systems are also considered as the added benefit. Results show that CHP requires a significant initial investment in return it can reduce the annual energy bill significantly. Results show that an investment may be paid back in 7 years. After the back period, CHP can run for about 3 years as most of the CHP manufacturers provide 10-year warranty.Keywords: combined heat and power, clean energy, hydrogen fuel cell, economic analysis of CHP, zero emission
Procedia PDF Downloads 3903060 Influence of Silicon Carbide Particle Size and Thermo-Mechanical Processing on Dimensional Stability of Al 2124SiC Nanocomposite
Authors: Mohamed M. Emara, Heba Ashraf
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This study is to investigation the effect of silicon carbide (SiC) particle size and thermo-mechanical processing on dimensional stability of aluminum alloy 2124. Three combinations of SiC weight fractions are investigated, 2.5, 5, and 10 wt. % with different SiC particle sizes (25 μm, 5 μm, and 100nm) were produced using mechanical ball mill. The standard testing samples were fabricated using powder metallurgy technique. Both samples, prior and after extrusion, were heated from room temperature up to 400ºC in a dilatometer at different heating rates, that is, 10, 20, and 40ºC/min. The analysis showed that for all materials, there was an increase in length change as temperature increased and the temperature sensitivity of aluminum alloy decreased in the presence of both micro and nano-sized silicon carbide. For all conditions, nanocomposites showed better dimensional stability compared to conventional Al 2124/SiC composites. The after extrusion samples showed better thermal stability and less temperature sensitivity for the aluminum alloy for both micro and nano-sized silicon carbide.Keywords: aluminum 2124 metal matrix composite, SiC nano-sized reinforcements, powder metallurgy, extrusion mechanical ball mill, dimensional stability
Procedia PDF Downloads 5303059 Innovating Development: An Exploratory Study of Social Enterprises in Nigeria
Authors: Akor Omachile Opaluwah
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Entrepreneurs are heralded as a very vital force in the growth of economies. This is because they create businesses, employ people, have direct access to the local consumer, and primarily utilize local sources of raw materials, have an understanding of the immediate need of consumers, and they have the capacity to keep in motion the economy. The rise of social enterprises takes these advantages further beyond the business and economic benefits. These Social enterprises help address developmental issues in the society while maintaining a profit for their investors and shareholders. These combined roles create a unique synergy between the civil society and the market, therefore placing the social enterprise in a position where they can access directly, the benefits of the market while meeting the needs of the citizens and their environment. With such a unique position, social enterprises hold a place in the development discourse that has previously been left unexplored. This hybridisation of the functions of civil societies and the market can provide to development, practices, and benefits that have previously been only available in trace amounts. It, therefore, is imperative to understand the efficacy of social enterprises. With the discourse of social enterprises still in its early stages. This paper looks at selected social enterprise cases in Nigeria and analyses their approach and contribution to development.Keywords: business, civil society, development, entrepreneurs, innovation, market, Nigeria, social enterprise
Procedia PDF Downloads 393