Search results for: criticism of design
4341 Analysis of Thermoelectric Coolers as Energy Harvesters for Low Power Embedded Applications
Authors: Yannick Verbelen, Sam De Winne, Niek Blondeel, Ann Peeters, An Braeken, Abdellah Touhafi
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The growing popularity of solid state thermoelectric devices in cooling applications has sparked an increasing diversity of thermoelectric coolers (TECs) on the market, commonly known as “Peltier modules”. They can also be used as generators, converting a temperature difference into electric power, and opportunities are plentiful to make use of these devices as thermoelectric generators (TEGs) to supply energy to low power, autonomous embedded electronic applications. Their adoption as energy harvesters in this new domain of usage is obstructed by the complex thermoelectric models commonly associated with TEGs. Low cost TECs for the consumer market lack the required parameters to use the models because they are not intended for this mode of operation, thereby urging an alternative method to obtain electric power estimations in specific operating conditions. The design of the test setup implemented in this paper is specifically targeted at benchmarking commercial, off-the-shelf TECs for use as energy harvesters in domestic environments: applications with limited temperature differences and space available. The usefulness is demonstrated by testing and comparing single and multi stage TECs with different sizes. The effect of a boost converter stage on the thermoelectric end-to-end efficiency is also discussed.Keywords: thermoelectric cooler, TEC, complementary balanced energy harvesting, step-up converter, DC/DC converter, energy harvesting, thermal harvesting
Procedia PDF Downloads 2554340 Study of the Adhesive Bond Effect on Electro-Mechanical Behaviour of Coupled Piezo Structural System
Authors: Rahul S. Raj
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Electro-mechanical impedance technique is a recently developed non-destructive method for structural health monitoring. This system comprises of piezo electric patch, bonded to the structure using an adhesive/epoxy and electrically excited to determine the health of the component. The subjected electric field actuates the PZT patch harmonically and imparts a force on the host structure. The structural response thus produced by the host component is in the form of peaks and valleys which further shows the admittance signatures of the structure for the given excitation frequency. Adhesives have the capability to change the structural signatures, in EMI technique, by transforming conductance and susceptance signatures. The static approximation provide a justifiable result where adhesive bond lines are thin and stiff. The epoxy adhesive bonds limits design flexibility due to poor bond strengths, hence to enhance the performance of the joints, a new technique is developed for joining PZT, i.e. the alloy bonding technique. It is a metallic joining compound which contains many active elements including Titanium, that reacts with the tenacious surface films of the ceramic and composites to create excellent bonds. This alloy-based bonding technique will be used for better strain interaction and rigorous stress transfer between PZT patch and the host structure.Keywords: EMI technique, conductance, susceptance, admittance, alloy bonding
Procedia PDF Downloads 1144339 The Photocatalytic Degradation of Acid Blue 25 Dye by Polypyrrole/Titanium Dioxide and Polypyrrole/Zinc Oxide Composites
Authors: Ljerka Kratofil Krehula, Martina Perlog, Jasmina Stjepanović, Vanja Gilja, Marijana Kraljić Roković, Zlata Hrnjak-Murgić
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The composite preparation of titanium dioxide and zinc oxide photocatalysts with the conductive polymers gives the opportunity to carry out the catalysis reactions not only under UV light but also under visible light. Such processes may efficiently use sunlight in degradation of different organic pollutants and present new design for wastewater treatment. The paper presents the preparation procedure, material characteristics and photocatalytic efficiency of polypyrrole/titanium dioxide and polypyrrole/zinc oxide composites (PPy/TiO2 and PPy/ZnO). The obtained composite samples were characterized by Fourier transform infrared spectroscopy (FTIR), UV-Vis spectroscopy and thermogravimetric analysis (TGA). The photocatalytic efficiency of the samples was determined following the decomposition of Acid Blue 25 dye (AB 25) under UV and visible light by UV/Vis spectroscopy. The efficiency of degradation is determined by total organic carbon content (TOC) after photocatalysis processes. The results show enhanced photocatalytic efficiency of the samples under visible light, so the prepared composite samples are recognized as efficient catalysts in degradation process of AB 25 dye. It can be concluded that the preparation of TiO2 or ZnO composites with PPy can serve as a very efficient method for the improvement of TiO2 and ZnO photocatalytic performance under visible light.Keywords: composite, photocatalysis, polypyrrole, titanium dioxide, zinc oxide
Procedia PDF Downloads 4744338 Investigation of the Effect of Teaching Thinking and Research Lesson by Cooperative and Traditional Methods on Creativity of Sixth Grade Students
Authors: Faroogh Khakzad, Marzieh Dehghani, Elahe Hejazi
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The present study investigates the effect of teaching a Thinking and Research lesson by cooperative and traditional methods on the creativity of sixth-grade students in Piranshahr province. The statistical society includes all the sixth-grade students of Piranshahr province. The sample of this studytable was selected by available sampling from among male elementary schools of Piranshahr. They were randomly assigned into two groups of cooperative teaching method and traditional teaching method. The design of the study is quasi-experimental with a control group. In this study, to assess students’ creativity, Abedi’s creativity questionnaire was used. Based on Cronbach’s alpha coefficient, the reliability of the factor flow was 0.74, innovation was 0.61, flexibility was 0.63, and expansion was 0.68. To analyze the data, t-test, univariate and multivariate covariance analysis were used for evaluation of the difference of means and the pretest and posttest scores. The findings of the research showed that cooperative teaching method does not significantly increase creativity (p > 0.05). Moreover, cooperative teaching method was found to have significant effect on flow factor (p < 0.05), but in innovation and expansion factors no significant effect was observed (p < 0.05).Keywords: cooperative teaching method, traditional teaching method, creativity, flow, innovation, flexibility, expansion, thinking and research lesson
Procedia PDF Downloads 3134337 Effect of the Concrete Cover on the Bond Strength of the FRP Wrapped and Non-Wrapped Reinforced Concrete Beam with Lap Splice under Uni-Direction Cyclic Loading
Authors: Rayed Alyousef, Tim Topper, Adil Al-Mayah
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Many of the reinforced concrete structures subject to cyclic load constructed before the modern bond and fatigue design code. One of the main issue face on exists structure is the bond strength of the longitudinal steel bar and the surrounding concrete. A lap splice is a common connection method to transfer the force between the steel rebar in a reinforced concrete member. Usually, the lap splice is the weak connection on the bond strength. Fatigue flexural loading imposes severe demands on the strength and ductility of the lap splice region in reinforced concrete structures and can lead to a brittle and sudden failure of the member. This paper investigates the effect of different concrete covers on the fatigue bond strength of reinforcing concrete beams containing a lap splice under a fatigue loads. It includes tests of thirty-seven beams divided into three groups. Each group has beams with 30 mm and 50 mm clear side and bottom concrete covers. The variables that were addressed where the concrete cover, the presence or absence of CFRP or GFRP sheet wrapping, the type of loading (monotonic or fatigue) and the fatigue load ranges. The test results showed that an increase in the concrete cover led to an increase in the bond strength under both monotonic and fatigue loading for both the unwrapped and wrapped beams. Also, the FRP sheets increased both the fatigue strength and the ductility for both the 30 mm and the 50 mm concrete covers.Keywords: bond strength, fatigue, Lap splice, FRp wrapping
Procedia PDF Downloads 4774336 Heat Exchanger Optimization of a Domestic Refrigerator with Separate Cooling Circuits
Authors: Tugba Tosun, Mert Tosun
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Cooling system performance and energy consumption in the bypass two-circuit cycle have been studied experimentally to find optimum evaporator type and geometry, capillary tube diameter and capillary length. Two types of evaporators, such as wire on the tube and finned tube evaporators were used for the experiments in the fresh food compartment. As capillary tube inner diameter and total length; 0.66 mm and 0.8mm, and 3000 mm and 3500 mm were selected as parameters, respectively. Experiments were performed at the 25⁰C ambient temperature while the average temperature of the fresh food compartment is kept at 5⁰C and the highest package temperature of the freezer compartment is kept at -18⁰C, which are defined in IEC 62552 European standard. The Design of Experiments (DOE) technique which is six sigma method has been used to indicate of effective parameters in the bypass two-circuit cycle. The experimental results revealed that the most effective parameter of the system is the evaporator type. Finned tube evaporator with 12 tube passes was found as the best option for the bypass two-circuit refrigeration cycle among the 8 different opportunities. The optimum cooling performance and the lowest energy consumption were provided with 0.66 mm capillary tube inner diameter and 3500 mm capillary tube length.Keywords: capillary tube, energy consumption, heat exchanger, refrigerator, separate cooling circuits
Procedia PDF Downloads 1534335 Dental Pathologies and Agriculture: Literature Review
Authors: Ricardo Andrés Márquez Ortiz
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Objective: The objective of this literature review is to compile updated information from studies that have addressed the association between dental pathologies and agriculture. Materials and method: The research carried out corresponds to a documentary study of ex post facto retrospective, historiographic, and bibliometric design. An exhaustive bibliographic review search was carried out in databases and the Internet, books and articles on dental anthropology, archeology, and dentistry, on the relationship between dental pathologies and agriculture in prehistoric and current populations from different parts of the world. Subsequently, data collection was carried out through the ATLAS.ti computer program. Conclusions: In an influential article by Turner, which addresses the correlation between caries and the way of subsistence of both prehistoric and modern populations (hunting and gathering, mixed and agricultural economies), an average of 1.3% was found in hunter-gatherer societies, and 10.4% in agricultural societies. Sreebny compared global grain supply data (rice, wheat and corn) with DMF (spoiled, lost and blocked) rates. He concluded that rice has no association with dental caries, corn has a negative correlation, and wheat has a positive correlation. Additionally, intensive monoculture agricultural production systems cause an increase in dental pathologies. Meanwhile, polyculture agriculture, which leads to a more varied diet, generates a better state of dental health.Keywords: dental pathologies, agricultural production systems, extensive agriculture, dental anthropology
Procedia PDF Downloads 324334 Physical Activity Participation Levels as Correlates of Cardiorespiratory Fitness of Senior High School Teachers in the Dormaa East District
Authors: Isaac Yeboah
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Physical activity (PA) is considered the best preventative tool for maintaining physical health and extending lifespan because it offers a range of benefits. However, for people to benefit from physical activity, it must be done at a level that can enhance fitness, health, and overall well-being. Therefore, this study aimed to determine the link between physical activity participation levels and cardiorespiratory fitness (CRF). The study employed the descriptive correlational design. The census sampling technique included all 190 teaching staff from the two senior high schools in the Dormaa East District. An adapted International Physical Activity Questionnaire (IPAQ) and standardized physical fitness tests were used for data collection. Descriptive statistics of frequency counts and percentages were used to answer the research questions, while inferential statistics of Pearson Product Moment Correlation and the independent sample t-test were used to test hypotheses one and two, respectively. A moderately negative (r = -.156) relationship existed between physical activity participation levels and CRF. Female teachers demonstrated a statistically significant value (p = .045) than males. The study concluded that the reported physical activity levels of the teachers did not reflect their CRF. The implication is that either the participants overestimated their physical activity participation levels or the intensity of the activities was not high enough to affect physiological changes. For the teachers' CRF to improve, it was suggested, among other things, that regular physical activity sessions of the appropriate mixes of FITT be organized.Keywords: physical activity, participation levels, cardiorespiratory fitness, sedentary lifestyle, teachers
Procedia PDF Downloads 574333 Academic Skills Enhancement in Secondary School Students Undertaking Tertiary Studies
Authors: Richard White, Anne Drabble, Maureen O’Neill
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The University of the Sunshine Coast (USC) offers secondary school students in the final two years of school (Years 11 and 12, 16 – 18 years of age) an opportunity to participate in a program which provides an accelerated pathway to tertiary studies. Whilst still at secondary school, the students undertake two first year university subjects that are required subjects in USC undergraduate degree programs. The program is called Integrated Learning Pathway (ILP) and offers a range of disciplines, including business, design, drama, education, and engineering. Between 2010 and 2014, 38% of secondary students who participated in an ILP program commenced undergraduate studies at USC following completion of secondary school studies. The research reported here considers “before and after” literacy and numeracy competencies of students to determine what impact participation in the ILP program has had on their academic skills. Qualitative and quantitative data has been gathered via numeracy and literacy testing of the students, and a survey asking the students to self-evaluate their numeracy and literacy skills, and reflect on their views of these academic skills. The research will enable improved targeting of teaching strategies so that students will acquire not only course-specific learning outcomes but also collateral academic skills. This enhancement of academic skills will improve undergraduate experience and improve student retention.Keywords: academic skills enhancement, accelerated pathways, improved teaching, student retention
Procedia PDF Downloads 2994332 Determination of Forced Convection Heat Transfer Performance in Lattice Geometric Heat Sinks
Authors: Bayram Sahin, Baris Gezdirici, Murat Ceylan, Ibrahim Ates
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In this experimental study, the effects of heat transfer and flow characteristics on lattice geometric heat sinks, where high rates of heat removal are required, were investigated. The design parameters were Reynolds number, the height of heat sink (H), horizontal (Sy) and vertical (Sx) distances between heat sinks. In the experiments, the Reynolds number ranged from 4000 to 20000; heat sink heights were (H) 20 mm and 40 mm; the distances (Sy) between the heat sinks in the flow direction were45 mm, 32 mm, 23.3 mm; the distances (Sx) between the heat sinks perpendicular to the flow direction were selected to be 23.3 mm, 12.5 mm and 6 mm. A total of 90 experiments were conducted and the maximum Nusselt number and minimum friction coefficient were targeted. Experimental results have shown that heat sinks in lattice geometry have a significant effect on heat transfer enhancement. Under the different experimental conditions, the highest increase in Nusselt number was 283% while the lowest increase was calculated as 66% as compared with the straight channel results. The lowest increase in the friction factor was also obtained as 173% according to the straight channel results. It is seen that the increase in heat sink height and flow velocity increased the level of turbulence in the channel, leading to higher Nusselt number and friction factor values.Keywords: forced convection, heat transfer enhancement, lattice geometric heat sinks, pressure drop
Procedia PDF Downloads 1844331 Influence of Concrete Cracking in the Tensile Strength of Cast-in Headed Anchors
Authors: W. Nataniel, B. Lima, J. Manoel, M. P. Filho, H. Marcos, Oliveira Mauricio, P. Ferreira
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Headed reinforcement bars are increasingly used for anchorage in concrete structures. Applications include connections in composite steel-concrete structures, such as beam-column joints, in several strengthening situations as well as in more traditional uses in cast-in-place and precast structural systems. This paper investigates the reduction in the ultimate tensile capacity of embedded cast-in headed anchors due to concrete cracking. A series of nine laboratory tests are carried out to evaluate the influence of cracking on the concrete breakout strength in tension. The experimental results show that cracking affects both the resistance and load-slip response of the headed bar anchors. The strengths measured in these tests are compared to theoretical resistances calculated following the recommendations presented by fib Bulletin no. 58 (2011), ETAG 001 (2010) and ACI 318 (2014). The influences of parameters such as the effective embedment depth (hef), bar diameter (ds), and the concrete compressive strength (fc) are analysed and discussed. The theoretical recommendations are shown to be over-conservative for both embedment depths and were, in general, inaccurate in comparison to the experimental trends. The ACI 318 (2014) was the design code which presented the best performance regarding to the predictions of the ultimate load, with an average of 1.42 for the ratio between the experimental and estimated strengths, standard deviation of 0.36, and coefficient of variation equal to 0.25.Keywords: cast-in headed anchors, concrete cone failure, uncracked concrete, cracked concrete
Procedia PDF Downloads 1974330 Baseline Study for Performance Evaluation of New Generation Solar Insulation Films for Windows: A Test Bed in Singapore
Authors: Priya Pawar, Rithika Susan Thomas, Emmanuel Blonkowski
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Due to the solar geometry of Singapore, which lay within the geographical classification of equatorial tropics, there is a great deal of thermal energy transfer to the inside of the buildings. With changing face of economic development of cities like Singapore, more and more buildings are designed to be lightweight using transparent construction materials such as glass. Increased demand for energy efficiency and reduced cooling load demands make it important for building designer and operators to adopt new and non-invasive technologies to achieve building energy efficiency targets. A real time performance evaluation study was undertaken at School of Art Design and Media (SADM), Singapore, to determine the efficiency potential of a new generation solar insulation film. The building has a window to wall ratio (WWR) of 100% and is fitted with high performance (low emissivity) double glazed units. The empirical data collected was then used to calibrate a computerized simulation model to understand the annual energy consumption based on existing conditions (baseline performance). It was found that the correlations of various parameters such as solar irradiance, solar heat flux, and outdoor air-temperatures quantification are significantly important to determine the cooling load during a particular period of testing.Keywords: solar insulation film, building energy efficiency, tropics, cooling load
Procedia PDF Downloads 1854329 A Saltwater Battery Inspired by the Membrane Potential Found in Biological Cells
Authors: Ross Lee, Pritpal Singh, Andrew Jester
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As the world transitions to a more sustainable energy economy, the deployment of energy storage technologies is expected to increase to develop a more resilient grid system. However, current technologies are associated with various environmental and safety issues throughout their entire lifecycle; therefore, new battery technology is necessary for grid applications to curtail these risks. Biological cells, such as human neurons and electrolytes in the electric eel, can serve as a more sustainable design template for a new bio-inspired (i.e., biomimetic) battery. Within biological cells, an electrochemical gradient across the cell membrane forms the membrane potential, which serves as the driving force for ion transport into/out of the cell, akin to the charging/discharging of a battery cell. This work serves as the first step to developing such a biomimetic battery cell, starting with the fabrication and characterization of ion-selective membranes to facilitate ion transport through the cell. Performance characteristics (e.g., cell voltage, power density, specific energy, roundtrip efficiency) for the cell under investigation are compared to incumbent battery technologies and biological cells to assess the readiness level for this emerging technology. Using a Na⁺-Form Nafion-117 membrane, the cell in this work successfully demonstrated behavior similar to human neurons; these findings will inform how cell components can be re-engineered to enhance device performance.Keywords: battery, biomimetic, electrolytes, human neurons, ion-selective membranes, membrane potential
Procedia PDF Downloads 1074328 The Role of Extrovert and Introvert Personality in Second Language Acquisition
Authors: Fatma Hsain Ali Suliman
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Personality plays an important role in acquiring a second language. For second language learners to make maximum progress with their own learning styles, their individual differences must be recognized and attended to. Personality is considered to be a pattern of unique characteristics that give a person’s behavior a kind of consistency and individuality. Therefore, the enclosed study, which is entitled “The Role of Personality in Second language Acquisition: Extroversion and Introversion”, tends to shed light on the relationship between learners’ personalities and second language acquisition process. In other words, it aims at drawing attention to how individual differences of students as being extroverts or introverts could affect the language acquisition process. As a literature review, this paper discusses the results of some studies concerning this issue as well as the point views of researchers and scholars who have focused on the effect of extrovert and introvert personality on acquiring a second language. To accomplish the goals of this study, which is divided into 5 chapters including introduction, review of related literature, research method and design, results and discussions and conclusions and recommendations, 20 students of English Department, Faculty of Arts, Misurata University, Libya were handed out a questionnaire to figure out the effect of their personalities on the learning process. Finally, to be more sure about the role of personality in a second language acquisition process, the same students who were given the questionnaire were observed in their ESL classes.Keywords: second language acquisition, personality, extroversion, introversion, individual differences, language learning strategy, personality factors, psycho linguistics
Procedia PDF Downloads 6394327 Enabling Integrated Production of Electric Vehicles in Automotive Final Assembly: Realization of an Expert Study
Authors: Achim Kampker, Heiner Hans Heimes, Mathias Ordung, Jan-Philip Ganser
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In the past years, the automotive industry has changed significantly. Innovative mobility concepts have become more important, and electric vehicles see a chance of replacing vehicles with combustion engines in the long term. However, the coming years will be characterized by coexistence. In this context, there are two possible production scenarios: One the one hand, electric vehicles could be manufactured in bespoke assembly lines. Concerning the uncertainty regarding sales figures development, this alternative boasts a high investment risk. Therefore, an integrated assembly building upon existing structures also seems a feasible solution. This empirical study aims at validating hypotheses concerning theoretical and practical challenges of the integrated production in the final assembly. In order to take a test of approaches of the research by analyzing censored feedback of professionals, these hypotheses are validated in the framework of an expert study. For this purpose, hypotheses have been generated on the basis of a requirements analysis and a concept specification. Thereupon, a list of question has been implemented and deduced from the hypotheses to execute an online- and written-survey and interviews with professionals. The interpretation and evaluation of the findings includes an inter-component comparison for the electric drivetrain. Furthermore, key drivers for a sufficient integrated product and process design are presented.Keywords: automotive industry, final assembly, integrated manufacturing, product and process development
Procedia PDF Downloads 3324326 Unlocking the Power of Social Media for Tourism Marketing: How Travel Bloggers Shape Destination Trust, Travel Intention with the Moderating Role of Trustworthiness on Social Media Posts
Authors: Saad Saif
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Tourism promotion in the digital age is significantly influenced by social media, particularly in developing travel markets such as Pakistan. This study examines how travel bloggers use social media to inspire people to plan journeys and increase trust in destinations. It examines how trustworthiness works as a moderator to enhance the legitimacy of social media posts. This study aims to comprehend the dynamics of social media's influence on the travel and tourism industry. This study investigates the influence of travel bloggers' content, with a focus on tone (positive/negative) and emotional intensity (strong/weak), on prospective Pakistani travelers' travel preferences and levels of trust toward a particular location. The study used an experimental design to validate its hypotheses. The results indicate that the emotive content and tone of bloggers influence travel intentions and that destination trust mediates this relationship. It is interesting to observe that variations in the emotional intensity of positive and negative ratings are not always accompanied by changes in destination trust and travel intent. In addition, the influence of a blogger's review tone on travel intention and destination trust is moderated by the credibility of online reviews, whereas the influence of emotional intensity on these outcomes is unaffected by review credibility.Keywords: tourism marketing, destination trust, travel intention, trustworthiness
Procedia PDF Downloads 644325 Development of a Research Platform to Revitalize People-Forest Relationship Through a Cycle of Architectural Embodiments
Authors: Hande Ünlü, Yu Morishita
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The total area of forest land in Japan accounts for 67% of the national land; however, despite this wealth and hundred years history of silviculture, today Japanese forestry faces socio-economic stagnation in forestry. While the growing gap in the people-forest relationship causes the depopulation of many forest villages, this paper introduces a methodology aiming to develop a place-specific approach in revitalizing this relationship. The paper focuses on a case study from Taiki town in the Hokkaido region to analyze the place's specific socio-economic requirements through interviews and workshops with the local experts, researchers, and stakeholders. Based on the analyzed facts, a master outline of design requirements is developed to produce locally sourced architectural embodiments that aim to act as a unifying element between the forests and the people of Taiki town. In parallel, the proposed methodology aims to generate a cycle of research feed and a researcher retreat, a definition given by Memu Earth Lab to the researchers' stay at Memu in Taiki town for a defined period to analyze local resources, for the continuous improvement of the introduced methodology to revitalize the interaction between people and forest through architecture.Keywords: architecture, Japanese forestry, local timber, people-forest relationship, research platform
Procedia PDF Downloads 1724324 Assessment of ASEI-PDSI Method on Students’ Attitude and Achievement in Junior Secondary Schools Mathematics in FCT-Abuja
Authors: Amenaghawon Clement Osemwinyen
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The Activity, Student-centred, Experiment, Improvisation - Plan, Do, See, Improve (ASEI-PDSI) method championed by the Strengthening Mathematics And Science Education (SMASE) - Nigeria Project is an attempt to improve the quality of mathematics, which has consistently declined over the years in both public primary and secondary schools across the country. The study thus assessed the ASEI-PDSI method on students’ attitudes and achievement in junior secondary schools (JSS) mathematics in FCT-Abuja. A survey research design was adopted, and 100 mathematics teachers using a stratified random sampling method were used for the study. The data were collected using structured questionnaires and analyzed using descriptive statistics. The findings showed that the ASEI-PDSI method had significantly improved the attitudes of students toward mathematics. The study also revealed that the ASEI-PDSI method significantly influenced junior secondary school (JSS) students’ mathematics achievement. Amongst the recommendations were that teachers should be encouraged to adopt the ASEI-PDSI method in teaching and learning mathematics in order to create a mathematically stimulating classroom environment which could advertently influence junior secondary school (JSS) students’ attitude and academic performance in mathematics. Also, regular in-service training programs should be organized by stakeholders (government and other interest groups) so as to improve the teaching strategies of teachers, mostly as they affect the ASEI-PDSI method.Keywords: achievement, ASEI-PDSI method, attitude, mathematics, SMASE
Procedia PDF Downloads 934323 Process Optimization for Albanian Crude Oil Characterization
Authors: Xhaklina Cani, Ilirjan Malollari, Ismet Beqiraj, Lorina Lici
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Oil characterization is an essential step in the design, simulation, and optimization of refining facilities. To achieve optimal crude selection and processing decisions, a refiner must have exact information refer to crude oil quality. This includes crude oil TBP-curve as the main data for correct operation of refinery crude oil atmospheric distillation plants. Crude oil is typically characterized based on a distillation assay. This procedure is reasonably well-defined and is based on the representation of the mixture of actual components that boil within a boiling point interval by hypothetical components that boil at the average boiling temperature of the interval. The crude oil assay typically includes TBP distillation according to ASTM D-2892, which can characterize this part of oil that boils up to 400 C atmospheric equivalent boiling point. To model the yield curves obtained by physical distillation is necessary to compare the differences between the modelling and the experimental data. Most commercial use a different number of components and pseudo-components to represent crude oil. Laboratory tests include distillations, vapor pressures, flash points, pour points, cetane numbers, octane numbers, densities, and viscosities. The aim of the study is the drawing of true boiling curves for different crude oil resources in Albania and to compare the differences between the modeling and the experimental data for optimal characterization of crude oil.Keywords: TBP distillation curves, crude oil, optimization, simulation
Procedia PDF Downloads 2944322 A Study of Police Culture Themes Towards the Public Among South African Police Service
Authors: Nkosingiphile M. Mbhele, Jean Steyn
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A focus group discussion was implemented, which comprised of senior South African Police Service managers and police academics in South Africa. The measurement of solidarity, isolation, and cynicism among functional South African Police Service officials and a thirty-item questionnaire came about by reviewing the literature. This research uses a survey format to assess the police culture theme of solidarity, isolation, and cynicism among South African Police Service officers in 9 South African provinces. Although a survey format is used in research, it engages in a quasi-experimental pre-test/post-test repeated measures research (longitudinal) design. Although there are differences among South African Police Service police (SAPS) officers, overall, there are signs of solidarity, isolation, and cynicism among SAPS members. Attitudes of solidarity, isolation, and cynicism are present among most police officials and have been presented from the start of training and held, maintained, or strengthened for the next years of their SAPS careers. This issue is problematic to society with regard to community-orientated policing since they have to interact with the members of the community. To author’s best knowledge, longitudinal studies of police culture are rare to find; not much has been researched on this topic. However, this paper offers to bridge that gap by providing answers to longitudinal police attitudes towards the public within the police culture themes of isolation and cynicism attitudes.Keywords: South African police service, police culture, solidarity, isolation, cynicism, public
Procedia PDF Downloads 1384321 Design of a Photovoltaic Power Generation System Based on Artificial Intelligence and Internet of Things
Authors: Wei Hu, Wenguang Chen, Chong Dong
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In order to improve the efficiency and safety of photovoltaic power generation devices, this photovoltaic power generation system combines Artificial Intelligence (AI) and the Internet of Things (IoT) to control the chasing photovoltaic power generation device to track the sun to improve power generation efficiency and then convert energy management. The system uses artificial intelligence as the control terminal, the power generation device executive end uses the Linux system, and Exynos4412 is the CPU. The power generating device collects the sun image information through Sony CCD. After several power generating devices feedback the data to the CPU for processing, several CPUs send the data to the artificial intelligence control terminal through the Internet. The control terminal integrates the executive terminal information, time information, and environmental information to decide whether to generate electricity normally and then whether to convert the converted electrical energy into the grid or store it in the battery pack. When the power generation environment is abnormal, the control terminal authorizes the protection strategy, the power generation device executive terminal stops power generation and enters a self-protection posture, and at the same time, the control terminal synchronizes the data with the cloud. At the same time, the system is more intelligent, more adaptive, and longer life.Keywords: photo-voltaic power generation, the pursuit of light, artificial intelligence, internet of things, photovoltaic array, power management
Procedia PDF Downloads 1154320 Selective Laser Melting (SLM) Process and Its Influence on the Machinability of TA6V Alloy
Authors: Rafał Kamiński, Joel Rech, Philippe Bertrand, Christophe Desrayaud
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Titanium alloys are among the most important material in the aircraft industry, due to its low density, high strength, and corrosion resistance. However, these alloys are considered as difficult to machine because they have poor thermal properties and high reactivity with cutting tools. The Selective Laser Melting (SLM) process becomes even more popular through industry since it enables the design of new complex components, that cannot be manufactured by standard processes. However, the high temperature reached during the melting phase as well as the several rapid heating and cooling phases, due to the movement of the laser, induce complex microstructures. These microstructures differ from conventional equiaxed ones obtained by casting+forging. Parts obtained by SLM have to be machined in order calibrate the dimensions and the surface roughness of functional surfaces. The ball milling technique is widely applied to finish complex shapes. However, the machinability of titanium is strongly influenced by the microstructure. So the objective of this work is to investigate the influence of the SLM process, i.e. microstructure, on the machinability of titanium, compared to conventional forming processes. The machinability is analyzed by measuring surface roughness, cutting forces, cutting tool wear for a range of cutting conditions (depth of cut ap, feed per tooth fz, spindle speed N) in accordance with industrial practices.Keywords: ball milling, microstructure, surface roughness, titanium
Procedia PDF Downloads 2884319 Impacts of Teachers’ Cluster Model Meeting Intervention on Pupils’ Learning, Academic Achievement and Attitudinal Development in Oyo State, Nigeria
Authors: Olusola Joseph Adesina, Abiodun Ezekiel Adesina
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Efforts at improving the falling standard of education in the country call for the need-based assessment of the primary tier of education in Nigeria. Teachers’ cluster meeting intervention is a step towards enhancing the teachers’ professional competency, efficient and effective pupils’ academic achievement and attitudinal development. The study thus determined the impact of the intervention on pupils’ achievement in Oyo State, Nigeria. Three research questions and four hypotheses guided the study. Pre-test, post-test control group, quasi-experimental design was adopted for the study. Eight intact classes from eight different schools were randomly selected into treatment and control groups. Two response instruments, pupils academic achievement test (PAAT; r = 0.87) and pupils attitude to lesson scale (PALS; r = 0.80) were used for data collection. Mean, standard deviation and analysis of covariance (ANCOVA) were used to analyse the collected data. The results showed that the teachers’ cluster meeting have significant impact on pupils academic achievement (F (1,327) =41.79; p<0.05) and attitudinal development (F (1,327) =26.01; p<0.05) in the core subjects of primary schools in Oyo State, Nigeria. The study therefore recommended among others that teachers’ cluster meeting should be sustained for teachers’ professional development and pupils’ upgradement in the State.Keywords: teachers’ cluster meeting, pupils’ academic achievement, pupils’ attitudinal development, academic achievement
Procedia PDF Downloads 4604318 Investigation on the Bogie Pseudo-Hunting Motion of a Reduced-Scale Model Railway Vehicle Running on Double-Curved Rails
Authors: Barenten Suciu, Ryoichi Kinoshita
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In this paper, an experimental and theoretical study on the bogie pseudo-hunting motion of a reduced-scale model railway vehicle, running on double-curved rails, is presented. Since the actual bogie hunting motion, occurring for real railway vehicles running on straight rails at high travelling speeds, cannot be obtained in laboratory conditions, due to the speed and wavelength limitations, a pseudo- hunting motion was induced by employing double-curved rails. Firstly, the test rig and the experimental procedure are described. Then, a geometrical model of the double-curved rails is presented. Based on such model, the variation of the carriage rotation angle relative to the bogies and the working conditions of the yaw damper are clarified. Vibration spectra recorded during vehicle travelling, on straight and double-curved rails, are presented and interpreted based on a simple vibration model of the railway vehicle. Ride comfort of the vehicle is evaluated according to the ISO 2631 standard, and also by using some particular frequency weightings, which account for the discomfort perceived during the reading and writing activities. Results obtained in this work are useful for the adequate design of the yaw dampers, which are used to attenuate the lateral vibration of the train car bodies.Keywords: double-curved rail, octave analysis, vibration model, ride comfort, railway vehicle
Procedia PDF Downloads 3064317 Statistical Analysis of Parameters Effects on Maximum Strain and Torsion Angle of FRP Honeycomb Sandwich Panels Subjected to Torsion
Authors: Mehdi Modabberifar, Milad Roodi, Ehsan Souri
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In recent years, honeycomb fiber reinforced plastic (FRP) sandwich panels have been increasingly used in various industries. Low weight, low price, and high mechanical strength are the benefits of these structures. However, their mechanical properties and behavior have not been fully explored. The objective of this study is to conduct a combined numerical-statistical investigation of honeycomb FRP sandwich beams subject to torsion load. In this paper, the effect of geometric parameters of the sandwich panel on the maximum shear strain in both face and core and angle of torsion in a honeycomb FRP sandwich structures in torsion is investigated. The effect of Parameters including core thickness, face skin thickness, cell shape, cell size, and cell thickness on mechanical behavior of the structure were numerically investigated. Main effects of factors were considered in this paper and regression equations were derived. Taguchi method was employed as experimental design and an optimum parameter combination for the maximum structure stiffness has been obtained. The results showed that cell size and face skin thickness have the most significant impacts on torsion angle, maximum shear strain in face and core.Keywords: finite element, honeycomb FRP sandwich panel, torsion, civil engineering
Procedia PDF Downloads 4074316 Revolutionizing Mobility: Decoding Electric Vehicles (EVs) and Hydrogen Fuel Cell Vehicles (HFCVs)
Authors: Samarjeet Singh, Shubhank Arya, Shubham Chauhan
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In recent years, the rise in carbon emissions and the widespread effects of global warming have brought new energy vehicles into the spotlight. Electric vehicles (EVs) and hydrogen fuel cell vehicles (HFCVs), both producing zero tailpipe emissions, are seen as promising alternatives. This paper examines the working, structural characteristics, and safety designs of EVs and HFCVs, comparing their carbon emissions, charging infrastructure, energy efficiency, and safety features. The analysis reveals that both EVs and HFCVs significantly reduce carbon emissions and enhance safety compared to traditional vehicles, with EVs showing greater emission reductions. Moreover, EVs are advancing more rapidly in terms of charging infrastructure compared to hydrogen energy vehicles. However, HFCVs exhibit lower energy efficiency than EVs. In terms of safety, both types surpass conventional vehicles, though EVs are more prone to overheating and fire hazards due to battery design issues. Current research suggests that EV technology and its supporting infrastructure are more comprehensive, cost-effective, and efficient in reducing carbon emissions. With continued investment in the development of new energy vehicles and potential advancements in hydrogen energy production, the future for HFCVs appears promising. The paper also expresses optimism for innovative solutions that could accelerate the growth of hydrogen energy vehicles.Keywords: electric vehicles, fuel cell electric vehicles, automotive engineering, energy transition
Procedia PDF Downloads 294315 Perception of Indoor Environmental Qualities in Residential Buildings: A Quantitative Case Survey for Turkey and Iran
Authors: Majid Bahramian, Kaan Yetilmezsoy
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Environmental performance of residential buildings been a hotspot for the research community, however, the indoor environmental quality significantly overlooked in the literature. The paper is motivated by the understanding of the occupants from the indoor environmental qualities and seeks to find the satisfaction level in two high-rise green-certified residential buildings. Views of more than 250 respondents in each building were solicited on 15 Indoor Environmental Qualities (IEQ) parameters. Findings suggest that occupants are generally satisfied with five critical aspects of IEQ, but some unsatisfaction exists during operation phase. The results also indicate that the green build certification systems for new buildings have some deficiencies which affect the actual environmental performance of green buildings during operation. Some reasons were suggested by the occupants of which the design-focus construction and lack of monitoring after certification were the most critical factors. Among the crucial criteria for environmental performance assessment of green buildings, energy saving, reduction of Greenhouse Gases (GHG) emissions, environmental impacts on neighborhood area, waste reduction and IEQs, were the most critical factors dominating the performance, in a descending order. This study provides valuable information on the performance of IEQ parameters of green building and gives a deeper understanding for stakeholders and companies involved in construction sector with the relevant feedback for their decision-making on current and future projects.Keywords: indoor environmental qualities, green buildings, occupant satisfaction, environmental performance
Procedia PDF Downloads 764314 Evaluation of Geotechnical Parameters at Nubian Habitations in Kurkur Area, Aswan, Egypt
Authors: R. E. Fat-Helbary, A. A. Abdel-latief, M. S. Arfa, Alaa Mostafa
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The Egyptian Government proposed a general plan, aiming at constructing new settlements for Nubian in south Aswan in different places around Nasser Lake, one of these settlements in Kurkur area. The Nubian habitations in Wadi Kurkur are located around 30 km southwest of Aswan City. This area are affecting by near distance earthquakes from Kalabsha faults system. The shallow seismic refraction technique was conducted at the study area, to evaluate the soil and rock material quality and geotechnical parameters, in addition to the detection of the subsurface ground model under the study area. The P and S-wave velocities were calculated. The surface layer has P-wave, velocity ranges from 900 m/sec to 1625 m/sec and S-wave velocity ranges from 650 m/sec to 1400 m/sec. On the other hand the bedrock has P-wave velocity ranges from 1300 m/sec to 1980 m/sec and S-wave velocity ranges from 1050 m/sec to1725 m/sec. Measuring Vp and Vs velocities together with bulk density are calculated and used to extract the mechanical properties and geotechnical parameters of the foundation material at the study area. Output of this study is very important for solving the problems, which associated with the construction of various civil engineering purposes, for land use planning and for earthquakes resistant structure design.Keywords: shallow seismic refraction technique, Kurkur area, p and s-wave velocities, geotechnical parameters, bulk density, Kalabsha faults
Procedia PDF Downloads 4184313 Freeform Lens System for Collimation SERS irradiation Radiation Produced by Biolayers which Deposit on High Quality Resonant System
Authors: Iuliia Riabenko, Konstantin Beloshenko, Sergey Shulga, Valeriy Shulga
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An optical system has been developed consisting of a TIR lens and an aspherical surface designed to collect Stokes radiation from biomolecules. The freeform material is SYLGARD-184, which provides a low level of noise associated with the luminescence of the substrate. The refractive index of SYLGARD-184 is 1.4028 for a wavelength of 632 nm, the Abbe number is 72, these material parameters make it possible to design the desired shape for the wavelength range of 640-700 nm. The system consists of a TIR lens, inside which is placed a high-quality resonant system consisting of a biomolecule and a metal colloid. This system can be described using the coupled oscillator model. The laser excitation radiation was fed through the base of the TIR lens. The sample was mounted inside the TIR lens at a distance of 8 mm from the base. As a result of Raman scattering of laser radiation, a Stokes bend appeared from the biolayer. The task of this work was that it was necessary to collect this radiation emitted at a 4π steradian angle. For this, an internal aspherical surface was used, which made it possible to defocus the beam emanating from the biolayer and direct its radiation to the borders of the TIR lens at the Brewster angle. The collated beam of Stokes radiation contains 97% of the energy scattered by the biolayer. Thus, a simple scheme was proposed for collecting and collimating the Stokes radiation of biomolecules.Keywords: TIR lens, freeform material, raman scattering, biolayer, brewster angle
Procedia PDF Downloads 1294312 Analysing the Permanent Deformation of Cohesive Subsoil Subject to Long Term Cyclic Train Loading
Authors: Natalie M. Wride, Xueyu Geng
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Subgrade soils of railway infrastructure are subjected to a significant number of load applications over their design life. The use of slab track on existing and future proposed rail links requires a reduced maintenance and repair regime for the embankment subgrade, due to restricted access to the subgrade soils for remediation caused by cyclic deformation. It is, therefore, important to study the deformation behaviour of soft cohesive subsoils induced as a result of long term cyclic loading. In this study, a series of oedometer tests and cyclic triaxial tests (10,000 cycles) have been undertaken to investigate the undrained deformation behaviour of soft kaolin. X-ray Computer Tomography (CT) scanning of the samples has been performed to determine the change in porosity and soil structure density from the sample microstructure as a result of the laboratory testing regime undertaken. Combined with the examination of excess pore pressures and strains obtained from the cyclic triaxial tests, the results are compared with an existing analytical solution for long term settlement considering repeated low amplitude loading. Modifications to the analytical solution are presented based on the laboratory analysis that shows good agreement with further test data.Keywords: creep, cyclic loading, deformation, long term settlement, train loading
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