Search results for: interrupted time series designs
17027 Study on Seismic Performance of Reinforced Soil Walls in Order to Offer Modified Pseudo Static Method
Authors: Majid Yazdandoust
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This study, tries to suggest a design method based on displacement using finite difference numerical modeling in reinforcing soil retaining wall with steel strip. In this case, dynamic loading characteristics such as duration, frequency, peak ground acceleration, geometrical characteristics of reinforced soil structure and type of the site are considered to correct the pseudo static method and finally introduce the pseudo static coefficient as a function of seismic performance level and peak ground acceleration. For this purpose, the influence of dynamic loading characteristics, reinforcement length, height of reinforced system and type of the site are investigated on seismic behavior of reinforcing soil retaining wall with steel strip. Numerical results illustrate that the seismic response of this type of wall is highly dependent to cumulative absolute velocity, maximum acceleration, and height and reinforcement length so that the reinforcement length can be introduced as the main factor in shape of failure. Considering the loading parameters, mechanically stabilized earth wall parameters and type of the site showed that the used method in this study leads to most efficient designs in comparison with other methods which are generally suggested in cods that are usually based on limit-equilibrium concept. The outputs show the over-estimation of equilibrium design methods in comparison with proposed displacement based methods here.Keywords: pseudo static coefficient, seismic performance design, numerical modeling, steel strip reinforcement, retaining walls, cumulative absolute velocity, failure shape
Procedia PDF Downloads 48517026 Design, Construction, Validation And Use Of A Novel Portable Fire Effluent Sampling Analyser
Authors: Gabrielle Peck, Ryan Hayes
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Current large scale fire tests focus on flammability and heat release measurements. Smoke toxicity isn’t considered despite it being a leading cause of death and injury in unwanted fires. A key reason could be that the practical difficulties associated with quantifying individual toxic components present in a fire effluent often require specialist equipment and expertise. Fire effluent contains a mixture of unreactive and reactive gases, water, organic vapours and particulate matter, which interact with each other. This interferes with the operation of the analytical instrumentation and must be removed without changing the concentration of the target analyte. To mitigate the need for expensive equipment and time-consuming analysis, a portable gas analysis system was designed, constructed and tested for use in large-scale fire tests as a simpler and more robust alternative to online FTIR measurements. The novel equipment aimed to be easily portable and able to run on battery or mains electricity; be able to be calibrated at the test site; be capable of quantifying CO, CO2, O2, HCN, HBr, HCl, NOx and SO2 accurately and reliably; be capable of independent data logging; be capable of automated switchover of 7 bubblers; be able to withstand fire effluents; be simple to operate; allow individual bubbler times to be pre-set; be capable of being controlled remotely. To test the analysers functionality, it was used alongside the ISO/TS 19700 Steady State Tube Furnace (SSTF). A series of tests were conducted to assess the validity of the box analyser measurements and the data logging abilities of the apparatus. PMMA and PA 6.6 were used to assess the validity of the box analyser measurements. The data obtained from the bench-scale assessments showed excellent agreement. Following this, the portable analyser was used to monitor gas concentrations during large-scale testing using the ISO 9705 room corner test. The analyser was set up, calibrated and set to record smoke toxicity measurements in the doorway of the test room. The analyser was successful in operating without manual interference and successfully recorded data for 12 of the 12 tests conducted in the ISO room tests. At the end of each test, the analyser created a data file (formatted as .csv) containing the measured gas concentrations throughout the test, which do not require specialist knowledge to interpret. This validated the portable analyser’s ability to monitor fire effluent without operator intervention on both a bench and large-scale. The portable analyser is a validated and significantly more practical alternative to FTIR, proven to work for large-scale fire testing for quantification of smoke toxicity. The analyser is a cheaper, more accessible option to assess smoke toxicity, mitigating the need for expensive equipment and specialist operators.Keywords: smoke toxicity, large-scale tests, iso 9705, analyser, novel equipment
Procedia PDF Downloads 7717025 The Digitalization of Occupational Health and Safety Training: A Fourth Industrial Revolution Perspective
Authors: Deonie Botha
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Digital transformation and the digitization of occupational health and safety training have grown exponentially due to a variety of contributing factors. The literature suggests that digitalization has numerous benefits but also has associated challenges. The aim of the paper is to develop an understanding of both the perceived benefits and challenges of digitalization in an occupational health and safety context in an effort to design and develop e-learning interventions that will optimize the benefits of digitalization and address the associated challenges. The paper proposes, deliberate and tests the design principles of an e-learning intervention to ensure alignment with the requirements of a digitally transformed environment. The results of the research are based on a literature review regarding the requirements and effect of the Fourth Industrial Revolution on learning and e-learning in particular. The findings of the literature review are enhanced with empirical research in the form of a case study conducted in an organization that designs and develops e-learning content in the occupational health and safety industry. The primary findings of the research indicated that: (i) The requirements of learners and organizations in respect of e-learning are different than previously (i.e., a pre-Fourth Industrial Revolution related work setting). (ii) The design principles of an e-learning intervention need to be aligned with the entire value chain of the organization. (iii) Digital twins support and enhance the design and development of e-learning. (iv)Learning should incorporate a multitude of sensory experiences and should not only be based on visual stimulation. (v) Data that are generated as a result of e-learning interventions should be incorporated into big data streams to be analyzed and to become actionable. It is therefore concluded that there is general consensus on the requirements that e-learning interventions need to adhere to in a digitally transformed occupational health and safety work environment. The challenge remains for organizations to incorporate data generated as a result of e-learning interventions into the digital ecosystem of the organization.Keywords: digitalization, training, fourth industrial revolution, big data
Procedia PDF Downloads 15617024 Optimizing Operation of Photovoltaic System Using Neural Network and Fuzzy Logic
Authors: N. Drir, L. Barazane, M. Loudini
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It is well known that photovoltaic (PV) cells are an attractive source of energy. Abundant and ubiquitous, this source is one of the important renewable energy sources that have been increasing worldwide year by year. However, in the V-P characteristic curve of GPV, there is a maximum point called the maximum power point (MPP) which depends closely on the variation of atmospheric conditions and the rotation of the earth. In fact, such characteristics outputs are nonlinear and change with variations of temperature and irradiation, so we need a controller named maximum power point tracker MPPT to extract the maximum power at the terminals of photovoltaic generator. In this context, the authors propose here to study the modeling of a photovoltaic system and to find an appropriate method for optimizing the operation of the PV generator using two intelligent controllers respectively to track this point. The first one is based on artificial neural networks and the second on fuzzy logic. After the conception and the integration of each controller in the global process, the performances are examined and compared through a series of simulation. These two controller have prove by their results good tracking of the MPPT compare with the other method which are proposed up to now.Keywords: maximum power point tracking, neural networks, photovoltaic, P&O
Procedia PDF Downloads 33917023 Investigation of Various Physical and Physiological Properties of Ethiopian Elite Men Distances Runners
Authors: Getaye Fisseha Gelaw
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The purpose of this study was to investigate the key physical and physiological characteristics of 16 elite male Ethiopian national team distance runners, who have an average age of 28.1±4.3 years, a height of 175.0 ±5.6 cm, a weight of 59.1 ±3.9 kg, a BMI of 19.6 ±1.5, and training age of 10.1 ±5.1 yrs. The average weekly distance is 196.3±13.8 km, the average 10,000m time is 27:14±0.5 min sec, the average half marathon time is 59:30±0.6 min sec, the average marathon time is 2hr 03min 39sec±0.02. In addition, the average Cooper test (12-minute run test) is 4525.4±139.7 meters, and the average VO2 max is 90.8±3.1ml/kg/m. All athletes have a high profile and compete on the international label, and according to the World Athletics athletes' ranking system in 2021, 56.3% of the 16 participants were platinum label status, while the remaining 43.7 % were gold label status-completed an incremental treadmill test for the assessment of VO2peak, submaximal running, lactate threshold and test during which they ran continuously at 21 km/h. The laboratory determined VO2peak was 91.4 ± 1.7 mL/kg/min with anaerobic threshold of 74.2±1.6 mL/min/Kg and VO2max 81%. The speed at the AT is 15.9 ±0.6 Kmh and the altitude is 4,0%. The respiratory compensation RC point was reached at 88.7±1.1 mL/min/Kg and 97% of VO2 max. On RCP, the speed is 17.6 ±0.4 km/h and the altitude/slope are 5.5% percent, and the speed at Maximum effort is 19.5 ±1.5 and the elevation is 6.0%. The data also suggest that Ethiopian distance top athletes have considerably higher VO2 max values than those found in earlier research.Keywords: long-distance running, Ethiopians, VO2 max, world athletics, anthropometric
Procedia PDF Downloads 12817022 Improvement of the Geometric of Dental Bridge Framework through Automatic Program
Authors: Rong-Yang Lai, Jia-Yu Wu, Chih-Han Chang, Yung-Chung Chen
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The dental bridge is one of the clinical methods of the treatment for missing teeth. The dental bridge is generally designed for two layers, containing the inner layer of the framework(zirconia) and the outer layer of the porcelain-fused to framework restorations. The design of a conventional bridge is generally based on the antagonist tooth profile so that the framework evenly indented by an equal thickness from outer contour. All-ceramic dental bridge made of zirconia have well demonstrated remarkable potential to withstand a higher physiological occlusal load in posterior region, but it was found that there is still the risk of all-ceramic bridge failure in five years. Thus, how to reduce the incidence of failure is still a problem to be solved. Therefore, the objective of this study is to develop mechanical designs for all-ceramic dental bridges framework by reducing the stress and enhancing fracture resistance under given loading conditions by finite element method. In this study, dental design software is used to design dental bridge based on tooth CT images. After building model, Bi-directional Evolutionary Structural Optimization (BESO) Method algorithm implemented in finite element software was employed to analyze results of finite element software and determine the distribution of the materials in dental bridge; BESO searches the optimum distribution of two different materials, namely porcelain and zirconia. According to the previous calculation of the stress value of each element, when the element stress value is higher than the threshold value, the element would be replaced by the framework material; besides, the difference of maximum stress peak value is less than 0.1%, calculation is complete. After completing the design of dental bridge, the stress distribution of the whole structure is changed. BESO reduces the peak values of principle stress of 10% in outer-layer porcelain and avoids producing tensile stress failure.Keywords: dental bridge, finite element analysis, framework, automatic program
Procedia PDF Downloads 28217021 Qualitative Analysis of Healthcare Providers and Administrators’ Perceptions, Expectations, Barriers, and Facilitators Towards Pharmacists in Mental Healthcare in Saudi Arabia
Authors: Badar Dhehawi A. Aldhafeeri
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Objective: To explore the views and experiences of healthcare providers (HCPs) and their expectations toward pharmacists in mental healthcare, in addition to their acceptance of new pharmacist roles. Barriers and facilitators that are emerging in the process of developing enhanced pharmacist-related roles were also explored. Methods: Qualitative semi-structured face-to-face interviews were conducted with HCPs who had worked in mental health services in Saudi Arabia. The data were thematically analysed using a constant comparison with NVivo software to develop a series of key themes from the interviews. Results: Most HCPs indicated that they rarely interacted with pharmacists. They expected pharmacists to educate both patients and other healthcare workers in the future. Concerns were raised regarding inadequate pharmacy education and lack of clinical training for pharmacists. Conclusion: This study revealed that interactions between HCPs and pharmacists concerning mental health are still limited. A communication strategy for addressing mental health issues should be developed among pharmacists and other HCPs.Keywords: pharmacist, pharmacy student, saudi arabia, qualitative research
Procedia PDF Downloads 9617020 A Sociological Investigation on the Population and Public Spaces of Nguyen Cong Tru, a Soviet-Style Collective Housing Complex in Hanoi in Regards to Its New Community-Focused Architectural Design
Authors: Duy Nguyen Do, Bart Julien Dewancker
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Many Soviet-style collective housing complexes (also known as KTT) were built since the 1960s in Hanoi to support the post-war population growth. Those low-rise buildings have created well-knitted, robust communities, so much to the point that in most complexes, all families in one housing block would know each other, occasionally interact and provide supports in need. To understand how the community of collective housing complexes have developed and maintained in order to adapt their advantages into modern housing designs, the study is executed on the site of Nguyen Cong Tru KTT. This is one of the oldest KTT in Hanoi, completed in 1954. The complex also has an unique characteristic that is closely related to its community: the symbiotic relationship with Hom – a flea market that has been co-developing with Nguyen Cong Tru KTT since its beginning. The research consists of three phases: the first phase is a sociological investigation with Nguyen Cong Tru KTT’s current residents and a site survey on the complex’s economic and architectural characteristics. In the second phase, the collected data is analyzed to find out people’s opinions with the KTT’s concerning their satisfaction with the current housing status, floor plan organization, community, the relationship between the KTT’s dedicated public spaces with the flea market and their usage. Simultaneously, the master plan and gathered information regarding current architectural characteristics of the complex are also inspected. On the third phase, the analyses’ results will provide information regarding the issues, positive trends and significant historical features of the complex’s architecture in order to generate suitable proposals for the redesigning project of Nguyen Cong Tru KTT, a design focused on vitalizing modern apartments’ communities.Keywords: collective house community, collective house public space, community-focused, redesigning Nguyen Cong Tru KTT, sociological investigation
Procedia PDF Downloads 36317019 On Enabling Miner Self-Rescue with In-Mine Robots using Real-Time Object Detection with Thermal Images
Authors: Cyrus Addy, Venkata Sriram Siddhardh Nadendla, Kwame Awuah-Offei
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Surface robots in modern underground mine rescue operations suffer from several limitations in enabling a prompt self-rescue. Therefore, the possibility of designing and deploying in-mine robots to expedite miner self-rescue can have a transformative impact on miner safety. These in-mine robots for miner self-rescue can be envisioned to carry out diverse tasks such as object detection, autonomous navigation, and payload delivery. Specifically, this paper investigates the challenges in the design of object detection algorithms for in-mine robots using thermal images, especially to detect people in real-time. A total of 125 thermal images were collected in the Missouri S&T Experimental Mine with the help of student volunteers using the FLIR TG 297 infrared camera, which were pre-processed into training and validation datasets with 100 and 25 images, respectively. Three state-of-the-art, pre-trained real-time object detection models, namely YOLOv5, YOLO-FIRI, and YOLOv8, were considered and re-trained using transfer learning techniques on the training dataset. On the validation dataset, the re-trained YOLOv8 outperforms the re-trained versions of both YOLOv5, and YOLO-FIRI.Keywords: miner self-rescue, object detection, underground mine, YOLO
Procedia PDF Downloads 8317018 Investigation of Scaling Laws for Stiffness and strength in Bioinspired Glass Sponge Structures Produced by Fused Filament Fabrication
Authors: Hassan Beigi Rizi, Harold Auradou, Lamine Hattali
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Various industries, including civil engineering, automotive, aerospace, and biomedical fields, are currently seeking novel and innovative high-performance lightweight materials to reduce energy consumption. Inspired by the structure of Euplectella Aspergillum Glass Sponges (EA-sponge), 2D unit cells were created and fabricated using a Fused Filament Fabrication (FFF) process with Polylactic acid (PLA) filaments. The stiffness and strength of bio-inspired EA-sponge lattices were investigated both experimentally and numerically under uniaxial tensile loading and are compared to three standard square lattices with diagonal struts (Designs B and C) and non-diagonal struts (Design D) reinforcements. The aim is to establish predictive scaling laws models and examine the deformation mechanisms involved. The results indicated that for the EA-sponge structure, the relative moduli and yield strength scaled linearly with relative density, suggesting that the deformation mechanism is stretching-dominated. The Finite element analysis (FEA), with periodic boundary conditions for volumetric homogenization, confirms these trends and goes beyond the experimental limits imposed by the FFF printing process. Therefore, the stretching-dominated behavior, investigated from 0.1 to 0.5 relative density, demonstrate that the study of EA-sponge structure can be exploited for the realization of square lattice topologies that are stiff and strong and have attractive potential for lightweight structural applications. However, the FFF process introduces an accuracy limitation, with approximately 10% error, making it challenging to print structures with a relative density below 0.2. Future work could focus on exploring the impact of different printing materials on the performance of EA-sponge structures.Keywords: bio-inspiration, lattice structures, fused filament fabrication, scaling laws
Procedia PDF Downloads 617017 Comparison Between a Droplet Digital PCR and Real Time PCR Method in Quantification of HBV DNA
Authors: Surangrat Srisurapanon, Chatchawal Wongjitrat, Navin Horthongkham, Ruengpung Sutthent
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HBV infection causes a potential serious public health problem. The ability to detect the HBV DNA concentration is of the importance and improved continuously. By using quantitative Polymerase Chain Reaction (qPCR), several factors in standardized; source of material, calibration standard curve and PCR efficiency are inconsistent. Digital PCR (dPCR) is an alternative PCR-based technique for absolute quantification using Poisson's statistics without requiring a standard curve. Therefore, the aim of this study is to compare the data set of HBV DNA generated between dPCR and qPCR methods. All samples were quantified by Abbott’s real time PCR and 54 samples with 2 -6 log10 HBV DNA were selected for comparison with dPCR. Of these 54 samples, there were two outlier samples defined as negative by dPCR. Of these two, samples were defined as negative by dPCR, whereas 52 samples were positive by both the tests. The difference between the two assays was less than 0.25 log IU/mL in 24/52 samples (46%) of paired samples; less than 0.5 log IU/mL in 46/52 samples (88%) and less than 1 log in 50/52 samples (96%). The correlation coefficient was r=0.788 and P-value <0.0001. Comparison to qPCR, data generated by dPCR tend to be the overestimation in the sample with low HBV DNA concentration and underestimated in the sample with high viral load. The variation in DNA by dPCR measurement might be due to the pre-amplification bias, template. Moreover, a minor drawback of dPCR is the large quantity of DNA had to be used when compare to the qPCR. Since the technology is relatively new, the limitations of this assay will be improved.Keywords: hepatitis B virus, real time PCR, digital PCR, DNA quantification
Procedia PDF Downloads 48117016 Improvement of Oran Sebkha Soil by Dredged Sediments from Chorfa Dam in Algeria
Authors: Z. Aloui-Labiod, H. Trouzine, M. S. Ghembaza
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Geotechnical properties of dredged sediment from Chorfa dam in Algeria and their mixtures (5%, 10%, 15%, 20%, and 25%)with bentonite were investigated through with bentonite were investigated through a series of laboratory experimental tests in order to investigate possibilities of their usage as a barrier against the spread out of the Sebkha of Oran in the northwest of Algeria. Grain size and Atterberg limits tests, chemical and mineral analyses, and compaction, vertical swelling, and horizontal and vertical permeability tests were performed on the soils and their mixtures using tap water and the salty Sebkha water. The results indicate that the bentonite specimens remolded and inundated with Sebkha salty water have less swell potential than those prepared with tap water. The addition of bentonite to Chorfa sediment increases the density, limit liquid, specific surface, and swell potential of the mixtures. Compaction tests show a decrease in the optimum moisture and an increase in maximum dry densities as the bentonite content increases. The horizontal and vertical permeabilities decrease relatively with the addition of bentonite.Keywords: dredged sediment, bentonite, salty water, barrier
Procedia PDF Downloads 42817015 Efficiency of Background Chlorine Residuals against Accidental Microbial Episode in Proto-Type Distribution Network (Rig) Using Central Composite Design (CCD)
Authors: Sajida Rasheed, Imran Hashmi, Luiza Campos, Qizhi Zhou, Kim Keu
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A quadratic model (p ˂ 0.0001) was developed by using central composite design of 50 experimental runs (42 non-center + 8 center points) to assess efficiency of background chlorine residuals in combating accidental microbial episode in a prototype distribution network (DN) (rig). A known amount of background chlorine residuals were maintained in DN and a required number of bacteria, Escherichia coli K-12 strain were introduced by an injection port in the pipe loop system. Samples were taken at various time intervals at different pipe lengths. Spread plate count was performed to count bacterial number. The model developed was significant. With microbial concentration and time (p ˂ 0.0001), pipe length (p ˂ 0.022), background chlorine residuals (p ˂ 0.07) and time^2 (p ˂ 0.09) as significant factors. The ramp function of variables shows that at the microbial count of 10^6, at 0.76 L/min, and pipe length of 133 meters, a background residual chlorine 0.16 mg/L was enough for complete inactivation of microbial episode in approximately 18 minutes.Keywords: central composite design (CCD), distribution network, Escherichia coli, residual chlorine
Procedia PDF Downloads 46217014 Climate Change Impact on Slope Stability: A Study of Slope Drainage Design and Operation
Authors: Elena Mugarza, Stephanie Glendinning, Ross Stirling, Colin Davies
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The effects of climate change and increased rainfall events on UK-based infrastructure are observable, with an increasing number being reported on in the national press. The fatal derailment at Stonehaven in 2020 prompted a wider review of Network Rail-owned earthworks assets. The event was indicated by the Rail Accident Investigation Branch (RAIB) to be caused by mis-installed drainage on the adjacent cutting. The slope failure on Snake Pass (public highway A57) was reportedly caused by significant water ingress following numerous storm events and resulted in the road’s closure for several months. This problem is only projected to continue with greater intensity and more prolonged rainfall events forecasted in the future. Subsequently, this project is designed to evaluate effective drainage trench design within infrastructure embankments, considering the capillary barrier phenomenon that may govern their deterioration and resultant failure. Theoretically, the differential between grain sizes of the embankment clays and gravels, customarily used in drainage trenches, would have a limiting effect on infiltration. As such, it is anticipated that the inclusion of an additional material with an intermediate grain size should improve the hydraulic conductivity across the drainage boundary. Multiple drainage designs will be studied using instrumentation within the drain and surrounding clays. Data from the real-world installation at the BIONICS embankment will be collected and compared with laboratory and Finite Element (FE) simulations. This research aims to reduce the risk of infrastructure slope failures by improving the resilience of earthwork drainage and lessening the consequential impact on transportation networks.Keywords: earthworks, slope drainage, transportation slopes, deterioration, capillary barriers, field study
Procedia PDF Downloads 5117013 Modelling and Simulation of Aero-Elastic Vibrations Using System Dynamic Approach
Authors: Cosmas Pandit Pagwiwoko, Ammar Khaled Abdelaziz Abdelsamia
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Flutter as a phenomenon of flow-induced and self-excited vibration has to be recognized considering its harmful effect on the structure especially in a stage of aircraft design. This phenomenon is also important for a wind energy harvester based on the fluttering surface due to its effective operational velocity range. This multi-physics occurrence can be presented by two governing equations in both fluid and structure simultaneously in respecting certain boundary conditions on the surface of the body. In this work, the equations are resolved separately by two distinct solvers, one-time step of each domain. The modelling and simulation of this flow-structure interaction in ANSYS show the effectiveness of this loosely coupled method in representing flutter phenomenon however the process is time-consuming for design purposes. Therefore, another technique using the same weak coupled aero-structure is proposed by using system dynamics approach. In this technique, the aerodynamic forces were calculated using singularity function for a range of frequencies and certain natural mode shapes are transformed into time domain by employing an approximation model of fraction rational function in Laplace variable. The representation of structure in a multi-degree-of-freedom coupled with a transfer function of aerodynamic forces can then be simulated in time domain on a block-diagram platform such as Simulink MATLAB. The dynamic response of flutter at certain velocity can be evaluated with another established flutter calculation in frequency domain k-method. In this method, a parameter of artificial structural damping is inserted in the equation of motion to assure the energy balance of flow and vibrating structure. The simulation in time domain is particularly interested as it enables to apply the structural non-linear factors accurately. Experimental tests on a fluttering airfoil in the wind tunnel are also conducted to validate the method.Keywords: flutter, flow-induced vibration, flow-structure interaction, non-linear structure
Procedia PDF Downloads 31517012 A Systemic Review and Comparison of Non-Isolated Bi-Directional Converters
Authors: Rahil Bahrami, Kaveh Ashenayi
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This paper presents a systematic classification and comparative analysis of non-isolated bi-directional DC-DC converters. The increasing demand for efficient energy conversion in diverse applications has spurred the development of various converter topologies. In this study, we categorize bi-directional converters into three distinct classes: Inverting, Non-Inverting, and Interleaved. Each category is characterized by its unique operational characteristics and benefits. Furthermore, a practical comparison is conducted by evaluating the results of simulation of each bi-directional converter. BDCs can be classified into isolated and non-isolated topologies. Non-isolated converters share a common ground between input and output, making them suitable for applications with minimal voltage change. They are easy to integrate, lightweight, and cost-effective but have limitations like limited voltage gain, switching losses, and no protection against high voltages. Isolated converters use transformers to separate input and output, offering safety benefits, high voltage gain, and noise reduction. They are larger and more costly but are essential for automotive designs where safety is crucial. The paper focuses on non-isolated systems.The paper discusses the classification of non-isolated bidirectional converters based on several criteria. Common factors used for classification include topology, voltage conversion, control strategy, power capacity, voltage range, and application. These factors serve as a foundation for categorizing converters, although the specific scheme might vary depending on contextual, application, or system-specific requirements. The paper presents a three-category classification for non-isolated bi-directional DC-DC converters: inverting, non-inverting, and interleaved. In the inverting category, converters produce an output voltage with reversed polarity compared to the input voltage, achieved through specific circuit configurations and control strategies. This is valuable in applications such as motor control and grid-tied solar systems. The non-inverting category consists of converters maintaining the same voltage polarity, useful in scenarios like battery equalization. Lastly, the interleaved category employs parallel converter stages to enhance power delivery and reduce current ripple. This classification framework enhances comprehension and analysis of non-isolated bi-directional DC-DC converters. The findings contribute to a deeper understanding of the trade-offs and merits associated with different converter types. As a result, this work aids researchers, practitioners, and engineers in selecting appropriate bi-directional converter solutions for specific energy conversion requirements. The proposed classification framework and experimental assessment collectively enhance the comprehension of non-isolated bi-directional DC-DC converters, fostering advancements in efficient power management and utilization.The simulation process involves the utilization of PSIM to model and simulate non-isolated bi-directional converter from both inverted and non-inverted category. The aim is to conduct a comprehensive comparative analysis of these converters, considering key performance indicators such as rise time, efficiency, ripple factor, and maximum error. This systematic evaluation provides valuable insights into the dynamic response, energy efficiency, output stability, and overall precision of the converters. The results of this comparison facilitate informed decision-making and potential optimizations, ensuring that the chosen converter configuration aligns effectively with the designated operational criteria and performance goals.Keywords: bi-directional, DC-DC converter, non-isolated, energy conversion
Procedia PDF Downloads 10017011 Stimulus-Dependent Polyrhythms of Central Pattern Generator Hardware
Authors: Le Zhao, Alain Nogaret
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We have built universal Central Pattern Generator (CPG) hardware by interconnecting Hodgkin-Huxley neurons with reciprocally inhibitory synapses. We investigate the dynamics of neuron oscillations as a function of the time delay between current steps applied to individual neurons. We demonstrate stimulus dependent switching between spiking polyrhythms and map the phase portraits of the neuron oscillations to reveal the basins of attraction of the system. We experimentally study the dependence of the attraction basins on the network parameters: the neuron response time and the strength of inhibitory connections.Keywords: central pattern generator, winnerless competition principle, artificial neural networks, synapses
Procedia PDF Downloads 47417010 Data Integrity between Ministry of Education and Private Schools in the United Arab Emirates
Authors: Rima Shishakly, Mervyn Misajon
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Education is similar to other businesses and industries. Achieving data integrity is essential in order to attain a significant supporting for all the stakeholders in the educational sector. Efficient data collect, flow, processing, storing and retrieving are vital in order to deliver successful solutions to the different stakeholders. Ministry of Education (MOE) in United Arab Emirates (UAE) has adopted ‘Education 2020’ a series of five-year plans designed to introduce advanced education management information systems. As part of this program, in 2010 MOE implemented Student Information Systems (SIS) to manage and monitor the students’ data and information flow between MOE and international private schools in UAE. This paper is going to discuss data integrity concerns between MOE, and private schools. The paper will clarify the data integrity issues and will indicate the challenges that face private schools in UAE.Keywords: education management information systems (EMIS), student information system (SIS), United Arab Emirates (UAE), ministry of education (MOE), (KHDA) the knowledge and human development authority, Abu Dhabi educational counsel (ADEC)
Procedia PDF Downloads 22217009 Let It Rain In Our Conscious To Flourish Our Individual Self Like A Sakura: The Balance Model From Ppt And Rain Spiritual Method Used In A Drugs Prevention Program For Teenagers In A Psychoeducational Manner
Authors: Moise Alin Ionuț Cornel
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In a pilot lesson of prevention of consumption drugs in a classroom of teenager`s where the school want them to know how to manage their thoughts and emotions to protect themself an to be strong in an possible environment of drugs consumption. At this classroom was applied the RAIN(Recognize, Accept, Investigation,Non-identify) spiritual method and the balance model from positive and transcultural psychotherapy (PPT) in a manner of a game play for them to understand the methods in an individual experience. The balance model from PPT with his 4 parts and used in 3 ways, and the RAIN spiritual method was used to see how the teenager`s can bring clarity about theirs individual self and how they spend the time and energy in the daily life. The 3 ways of how they can used this model was explained like a analogy with the 3 periods of the SAKURA (Japanese cherry) flourish (kaika, mankai and chiru). The teenager`s received a new perspective and in the same time new tools from the spiritual point of view combined with the psychotherapeutic point of view to manage their thoughts, emotions, time and energy in the form of a psychoeducational game to be able to prevent the use of drugs.Keywords: addiction, drugs consumption prevention education, psychotherapy, Self, Spirituality, teenagers
Procedia PDF Downloads 7017008 Observations of Conformity in the Health Professions
Authors: Tanya Beran, Michelle Drefs, Ghazwan Altabbaa, Nouf Al Harbi, Noof Al Baz, Elizabeth Oddone Paolucci
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Although research shows that interprofessional practice has desirable effects on patient care, its implementation can present challenges to its team members. In particular, they may feel pressured to agree with or conform to other members who share information that is contrary to their own understanding. Obtaining evidence of this phenomenon is challenging, as team members may underreport their conformity behaviors due to reasons such as social desirability. In this paper, a series of studies are reviewed in which several approaches to assessing conformity in the health care professions are tested. Simulations, questionnaires, and behavior checklists were developed to measure conformity behaviors. Insights from these studies show that a significant proportion of people conform either in the presence or absence of others, express a variety of verbal and nonverbal behaviors when considering whether to conform to others, may shift between conforming and moments later not conforming (and vice versa), and may not accurately report whether they conformed. A new method of measuring conformity using the implicit bias test is also discussed. People at all levels in the healthcare system are encouraged to develop both formal and informal.Keywords: conformity, decision-making, inter-professional teams, simulation
Procedia PDF Downloads 16717007 Challenges That People with Autism and Caregivers Face in Public Environments
Authors: Andrei Pomana, Graham Brewer
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Autism is a lifelong developmental disorder that affects verbal and non-verbal communication, behaviour and sensory processing. As a result, people on the autism spectrum have a difficult time when confronted with environments that have high levels of sensory stimulation. This is often compounded by the inability to properly communicate their wants and needs to caregivers. The capacity for people with autism to integrate depends on their ability to at least tolerate highly stimulating public environments for short periods of time. The overall challenges that people on the spectrum and their caregivers face need to be established in order to properly create and assess methods to mitigate the effects of high stimulus public spaces. The paper aims to identify the challenges that people on the autism spectrum and their caregivers face in typical public environments. Nine experienced autism therapists have participated in a semi-structured interview regarding the challenges that people with autism and their caregivers face in public environments. The qualitative data shows that the unpredictability of events and the high sensory stimulation present in public environments, especially auditory, are the two biggest contributors to the difficulties that people on the spectrum face. If the stimuli are not removed in a short period of time, uncontrollable behaviours or 'meltdowns' can occur, which leave the person incapacitated and unable to respond to any outside input. Possible solutions to increase integration in public spaces for people with autism revolve around removing unwanted sensory stimulus, creating personalized barriers for certain stimuli, equipping people with autism with better tools to communicate their needs or to orient themselves to a safe location and providing a predictable pattern of events that would prepare individuals for tasks ahead of time.Keywords: autism, built environment, meltdown, public environment, sensory processing disorders
Procedia PDF Downloads 16317006 Unspoken Delights: Creative Strategies for Bypass Censorship System and Depicting Male-Female Relationships in Iranian Cinema
Authors: Parsa Naji
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Following the Iran Islamic Revolution in 1979 and the subsequent formation of a theocratic regime, the new regime implemented stringent regulations and a complicated censorship system in the film industry. Thereupon, the screening of films showing the relationships between males and females encountered numerous limitations. Not only did these limits encompass the physical portrayal of the relationship between males and females, but also the dialogues containing explicit sexual or even passionate romantic themes, resulting in a film being permanently consigned to archival storage. However, despite these limitations, Iranian filmmakers persevered in creating their interesting cinematic works. Throughout the years after the revolution, Iranian directors have navigated a series of challenges and obstacles, employing innovative and unconventional methods to bypass the rigorous censorship system imposed by the government, ensuring the screening of their films. This study aims to analyze the creative approaches employed by Iranian filmmakers to circumvent governmental censorship regulations.Keywords: censorship, Iranian cinema, Islamic revolution, male-female relationship
Procedia PDF Downloads 4717005 Trajectories of Physical Activity Intensity and Associated Factors in Men and Women from Elsa-Brasil
Authors: André Luis Messias Dos Santos Duque, Daniela Polessa Paula, Rosane Harter Griep
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The intensity of physical activity (PA) over time is essential for health promotion. However, there are few studies that have analyzed the practice of different intensities of PA longitudinally. The objective was to identify PA intensity trajectories in men and women from a Brazilian multicentric cohort and their associated factors. Data from 10,367 participants (5,777 women and 4,590 men) aged 35 to 74 years from the baseline and two follow-up visits (2012-2014 and 2017-2019) of the Longitudinal Study of Adult Health (ELSA-Brasil) were analyzed. PA intensity (low, moderate, or high) was assessed using the leisure-time PA module of the International Physical Activity Questionnaire (IPAQ), and sociodemographic, behavioral, and clinical variables were included. Chi-square and T-student tests were used, considering a significant level of 5%. Four intensity trajectories were identified: low, moderate, high, and no pattern. Most participants (82.5% of women and 75.7% of men) had low PA intensity trajectories, and only 2% of women and 4.8% of men had high PA intensity trajectories. For both sexes, a significant difference (p<0.05) was found for age group, education level, income, smoking, type 2 diabetes, obesity, hypertriglyceridemia, and hypertension. Actions that promote the practice of high-intensity PA over time and consider sociodemographic, clinical, and behavioral factors are necessary.Keywords: lifestyle, longterm effects, physical activity, socioeconomic factors
Procedia PDF Downloads 1617004 Innovative Methods of Improving Train Formation in Freight Transport
Authors: Jaroslav Masek, Juraj Camaj, Eva Nedeliakova
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The paper is focused on the operational model for transport the single wagon consignments on railway network by using two different models of train formation. The paper gives an overview of possibilities of improving the quality of transport services. Paper deals with two models used in problematic of train formatting - time continuously and time discrete. By applying these models in practice, the transport company can guarantee a higher quality of service and expect increasing of transport performance. The models are also applicable into others transport networks. The models supplement a theoretical problem of train formation by new ways of looking to affecting the organization of wagon flows.Keywords: train formation, wagon flows, marshalling yard, railway technology
Procedia PDF Downloads 43717003 Iot Device Cost Effective Storage Architecture and Real-Time Data Analysis/Data Privacy Framework
Authors: Femi Elegbeleye, Omobayo Esan, Muienge Mbodila, Patrick Bowe
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This paper focused on cost effective storage architecture using fog and cloud data storage gateway and presented the design of the framework for the data privacy model and data analytics framework on a real-time analysis when using machine learning method. The paper began with the system analysis, system architecture and its component design, as well as the overall system operations. The several results obtained from this study on data privacy model shows that when two or more data privacy model is combined we tend to have a more stronger privacy to our data, and when fog storage gateway have several advantages over using the traditional cloud storage, from our result shows fog has reduced latency/delay, low bandwidth consumption, and energy usage when been compare with cloud storage, therefore, fog storage will help to lessen excessive cost. This paper dwelt more on the system descriptions, the researchers focused on the research design and framework design for the data privacy model, data storage, and real-time analytics. This paper also shows the major system components and their framework specification. And lastly, the overall research system architecture was shown, its structure, and its interrelationships.Keywords: IoT, fog, cloud, data analysis, data privacy
Procedia PDF Downloads 9917002 Characterization of the Dispersion Phenomenon in an Optical Biosensor
Authors: An-Shik Yang, Chin-Ting Kuo, Yung-Chun Yang, Wen-Hsin Hsieh, Chiang-Ho Cheng
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Optical biosensors have become a powerful detection and analysis tool for wide-ranging applications in biomedical research, pharmaceuticals and environmental monitoring. This study carried out the computational fluid dynamics (CFD)-based simulations to explore the dispersion phenomenon in the microchannel of a optical biosensor. The predicted time sequences of concentration contours were utilized to better understand the dispersion development occurred in different geometric shapes of microchannels. The simulation results showed the surface concentrations at the sensing probe (with the best performance of a grating coupler) in respect of time to appraise the dispersion effect and therefore identify the design configurations resulting in minimum dispersion.Keywords: CFD simulations, dispersion, microfluidic, optical waveguide sensors
Procedia PDF Downloads 54517001 Advanced Exergetic Analysis: Decomposition Method Applied to a Membrane-Based Hard Coal Oxyfuel Power Plant
Authors: Renzo Castillo, George Tsatsaronis
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High-temperature ceramic membranes for air separation represents an important option to reduce the significant efficiency drops incurred in state-of-the-art cryogenic air separation for high tonnage oxygen production required in oxyfuel power stations. This study is focused on the thermodynamic analysis of two power plant model designs: the state-of-the-art supercritical 600ᵒC hard coal plant (reference power plant Nordrhein-Westfalen) and the membrane-based oxyfuel concept implemented in this reference plant. In the latter case, the oxygen is separated through a mixed-conducting hollow fiber perovskite membrane unit in the three-end operation mode, which has been simulated under vacuum conditions on the permeate side and at high-pressure conditions on the feed side. The thermodynamic performance of each plant concept is assessed by conventional exergetic analysis, which determines location, magnitude and sources of efficiency losses, and advanced exergetic analysis, where endogenous/exogenous and avoidable/unavoidable parts of exergy destruction are calculated at the component and full process level. These calculations identify thermodynamic interdependencies among components and reveal the real potential for efficiency improvements. The endogenous and exogenous exergy destruction portions are calculated by the decomposition method, a recently developed straightforward methodology, which is suitable for complex power stations with a large number of process components. Lastly, an improvement priority ranking for relevant components, as well as suggested changes in process layouts are presented for both power stations.Keywords: exergy, carbon capture and storage, ceramic membranes, perovskite, oxyfuel combustion
Procedia PDF Downloads 18517000 Ramadan and Ethical Integrity in the United Arab Emirates
Authors: Gabriel Andrade
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Background: Ramadan is a time of intense religious salience in the Islamic world. Apart from ritual engagement, it is also a time for reflection on devotion and shared humanity. This prompts the issue if Ramadan has an effect on moral integrity and decision-making. Methods: The present study seeks to answer that question. A group of Muslim students in the United Arab Emirates (UAE) were assessed on moral integrity both during and after Ramadan. Results: Results came out showing that Ramadan has no significant effect on participants’ moral integrity. Conclusion: It is concluded that Ramadan has no effect on participants’ moral behavior, and this is potentially explained by the UAE’s increased secularization in recent decades.Keywords: Ramadan, United Arab Emirates, moral integrity, secularization, trolley dilemmas
Procedia PDF Downloads 4216999 Teaching Academic Vocabulary: A Recent and Old Approach
Authors: Sara Fine-Meltzer
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An obvious, but ill-addressed hindrance to reading comprehension in academic English is poor vocabulary. Unfortunately, dealing with the problem is usually delayed until university entrance. It is the contention of this paper that the chore should be confronted much earlier and by using a very old-fashioned method. This presentation is accompanied by vocabulary lists for advanced level university students with explanations concerning the content and justification for the 500-word lists: how they change over time in accordance with evolving styles of academic writing. There are also sample quizzes and methods to ensure that the words are “absorbed” over time. There is a discussion of other vocabulary acquisition methods and conclusions drawn from the drawbacks of such methods. The paper concludes with the rationale for beginning the study of “academic” vocabulary earlier than is generally acceptable.Keywords: academic vocabulary, old-fashioned methods, quizzes, vocabulary lists
Procedia PDF Downloads 12216998 Electret: A Solution of Partial Discharge in High Voltage Applications
Authors: Farhina Haque, Chanyeop Park
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The high efficiency, high field, and high power density provided by wide bandgap (WBG) semiconductors and advanced power electronic converter (PEC) topologies enabled the dynamic control of power in medium to high voltage systems. Although WBG semiconductors outperform the conventional Silicon based devices in terms of voltage rating, switching speed, and efficiency, the increased voltage handling properties, high dv/dt, and compact device packaging increase local electric fields, which are the main causes of partial discharge (PD) in the advanced medium and high voltage applications. PD, which occurs actively in voids, triple points, and airgaps, is an inevitable dielectric challenge that causes insulation and device aging. The aging process accelerates over time and eventually leads to the complete failure of the applications. Hence, it is critical to mitigating PD. Sharp edges, airgaps, triple points, and bubbles are common defects that exist in any medium to high voltage device. The defects are created during the manufacturing processes of the devices and are prone to high-electric-field-induced PD due to the low permittivity and low breakdown strength of the gaseous medium filling the defects. A contemporary approach of mitigating PD by neutralizing electric fields in high power density applications is introduced in this study. To neutralize the locally enhanced electric fields that occur around the triple points, airgaps, sharp edges, and bubbles, electrets are developed and incorporated into high voltage applications. Electrets are electric fields emitting dielectric materials that are embedded with electrical charges on the surface and in bulk. In this study, electrets are fabricated by electrically charging polyvinylidene difluoride (PVDF) films based on the widely used triode corona discharge method. To investigate the PD mitigation performance of the fabricated electret films, a series of PD experiments are conducted on both the charged and uncharged PVDF films under square voltage stimuli that represent PWM waveform. In addition to the use of single layer electrets, multiple layers of electrets are also experimented with to mitigate PD caused by higher system voltages. The electret-based approach shows great promise in mitigating PD by neutralizing the local electric field. The results of the PD measurements suggest that the development of an ultimate solution to the decades-long dielectric challenge would be possible with further developments in the fabrication process of electrets.Keywords: electrets, high power density, partial discharge, triode corona discharge
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