Search results for: optimal capacitors placement
2039 Real-Time Nonintrusive Heart Rate Measurement: Comparative Case Study of LED Sensorics' Accuracy and Benefits in Heart Monitoring
Authors: Goran Begović
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In recent years, many researchers are focusing on non-intrusive measuring methods when it comes to human biosignals. These methods provide solutions for everyday use, whether it’s health monitoring or finessing the workout routine. One of the biggest issues with these solutions is that the sensors’ accuracy is highly variable due to many factors, such as ambiental light, skin color diversity, etc. That is why we wanted to explore different outcomes under those kinds of circumstances in order to find the most optimal algorithm(s) for extracting heart rate (HR) information. The optimization of such algorithms can benefit the wider, cheaper, and safer application of home health monitoring, without having to visit medical professionals as often when it comes to observing heart irregularities. In this study, we explored the accuracy of infrared (IR), red, and green LED sensorics in a controlled environment and compared the results with a medically accurate ECG monitoring device.Keywords: data science, ECG, heart rate, holter monitor, LED sensors
Procedia PDF Downloads 1272038 Mathematical Modeling for the Break-Even Point Problem in a Non-homogeneous System
Authors: Filipe Cardoso de Oliveira, Lino Marcos da Silva, Ademar Nogueira do Nascimento, Cristiano Hora de Oliveira Fontes
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This article presents a mathematical formulation for the production Break-Even Point problem in a non-homogeneous system. The optimization problem aims to obtain the composition of the best product mix in a non-homogeneous industrial plant, with the lowest cost until the breakeven point is reached. The problem constraints represent real limitations of a generic non-homogeneous industrial plant for n different products. The proposed model is able to solve the equilibrium point problem simultaneously for all products, unlike the existing approaches that propose a resolution in a sequential way, considering each product in isolation and providing a sub-optimal solution to the problem. The results indicate that the product mix found through the proposed model has economical advantages over the traditional approach used.Keywords: branch and bound, break-even point, non-homogeneous production system, integer linear programming, management accounting
Procedia PDF Downloads 2112037 A New Method for Fault Detection
Authors: Mehmet Hakan Karaata, Ali Hamdan, Omer Yusuf Adam Mohamed
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Consider a distributed system that delivers messages from a process to another. Such a system is often required to deliver each message to its destination regardless of whether or not the system components experience arbitrary forms of faults. In addition, each message received by the destination must be a message sent by a system process. In this paper, we first identify the necessary and sufficient conditions to detect some restricted form of Byzantine faults referred to as modifying Byzantine faults. An observable form of a Byzantine fault whose effect is limited to the modification of a message metadata or content, timing and omission faults, and message replay is referred to as a modifying Byzantine fault. We then present a distributed protocol to detect modifying Byzantine faults using optimal number of messages over node-disjoint paths.Keywords: Byzantine faults, distributed systems, fault detection, network protocols, node-disjoint paths
Procedia PDF Downloads 4482036 Room Level Indoor Localization Using Relevant Channel Impulse Response Parameters
Authors: Raida Zouari, Iness Ahriz, Rafik Zayani, Ali Dziri, Ridha Bouallegue
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This paper proposes a room level indoor localization algorithm based on the use Multi-Layer Neural Network (MLNN) classifiers and one versus one strategy. Seven parameters of the Channel Impulse Response (CIR) were used and Gram-Shmidt Orthogonalization was performed to study the relevance of the extracted parameters. Simulation results show that when relevant CIR parameters are used as position fingerprint and when optimal MLNN architecture is selected good room level localization score can be achieved. The current study showed also that some of the CIR parameters are not correlated to the location and can decrease the localization performance of the system.Keywords: mobile indoor localization, multi-layer neural network (MLNN), channel impulse response (CIR), Gram-Shmidt orthogonalization
Procedia PDF Downloads 3582035 Application of Freeze Desalination for Tace elements Removal from Water
Authors: Fekadu Melak, Tsegaye Girma Asere
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Trace element ions, such as Cr(VI) and F−, are of particular interest due to their environmental impact. Both ions exhibit an anionic nature in water that can show similar removal tendencies except for their significant differences in ionic radius. Accordingly, partial freezing was performed to examine freeze separation efficiencies of Cr(VI) and F– from aqueous solutions. Real groundwater and simulated wastewater were included to test effeciency of F– and Cr(VI), respectively. Parameters such as initial ion concentration, salt addition, and freeze duration were explored. Under optimal operating conditions, freeze separation efficiencies of 90 ± 0.12 to 97 ± 0.54% and 58 ± 0.23% to 60 ± 0.34% from 5 mg/L of Cr(VI) and F–, respectively, were demonstrated. The F– ion intercalation into the ice, initiating the decrement of freeze separation efficiency was observed in the salt addition processes. The influences of structuring-destructuring (kosmotropicity-chaotropicity) and the size-exclusion nature of ice crystals were used to explain the plausible mechanism in freeze separation efficiency trace elemental ions.Keywords: Cr(VI), F-, partial freezing, size exclusion
Procedia PDF Downloads 832034 The Use Support Vector Machine and Back Propagation Neural Network for Prediction of Daily Tidal Levels Along The Jeddah Coast, Saudi Arabia
Authors: E. A. Mlybari, M. S. Elbisy, A. H. Alshahri, O. M. Albarakati
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Sea level rise threatens to increase the impact of future storms and hurricanes on coastal communities. Accurate sea level change prediction and supplement is an important task in determining constructions and human activities in coastal and oceanic areas. In this study, support vector machines (SVM) is proposed to predict daily tidal levels along the Jeddah Coast, Saudi Arabia. The optimal parameter values of kernel function are determined using a genetic algorithm. The SVM results are compared with the field data and with back propagation (BP). Among the models, the SVM is superior to BPNN and has better generalization performance.Keywords: tides, prediction, support vector machines, genetic algorithm, back-propagation neural network, risk, hazards
Procedia PDF Downloads 4682033 Electrochemical Detection of Hydroquinone by Square Wave Voltammetry Using a Zn Layered Hydroxide-Ferulate Modified Multiwall Carbon Nanotubes Paste Electrode
Authors: Mohamad Syahrizal Ahmad, Illyas M. Isa
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In this paper, a multiwall carbon nanotubes (MWCNT) paste electrode modified by a Zn layered hydroxide-ferulate (ZLH-F) was used for detection of hydroquinone (HQ). The morphology and characteristic of the ZLH-F/MWCNT were investigated by scanning electron microscope (SEM), transmission electron microscope (TEM) and square wave voltammetry (SWV). Under optimal conditions, the SWV response showed linear plot for HQ concentration in the range of 1.0×10⁻⁵ M – 1.0×10⁻³ M. The detection limit was found to be 5.7×10⁻⁶ M and correlation coefficient of 0.9957. The glucose, fructose, sucrose, bisphenol A, acetaminophen, lysine, NO₃⁻, Cl⁻ and SO₄²⁻ did not interfere the HQ response. This modified electrode can be used to determine HQ content in wastewater and cosmetic cream with range of recovery 97.8% - 103.0%.Keywords: 1, 4-dihydroxybenzene, hydroquinone, multiwall carbon nanotubes, square wave voltammetry
Procedia PDF Downloads 2292032 Logistics Hub Location and Scheduling Model for Urban Last-Mile Deliveries
Authors: Anastasios Charisis, Evangelos Kaisar, Steven Spana, Lili Du
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Logistics play a vital role in the prosperity of today’s cities, but current urban logistics practices are proving problematic, causing negative effects such as traffic congestion and environmental impacts. This paper proposes an alternative urban logistics system, leasing hubs inside cities for designated time intervals, and using handcarts for last-mile deliveries. A mathematical model for selecting the locations of hubs and allocating customers, while also scheduling the optimal times during the day for leasing hubs is developed. The proposed model is compared to current delivery methods requiring door-to-door truck deliveries. It is shown that truck traveled distances decrease by more than 60%. In addition, analysis shows that in certain conditions the approach can be economically competitive and successfully applied to address real problems.Keywords: hub location, last-mile, logistics, optimization
Procedia PDF Downloads 1942031 Optimization Analysis of a Concentric Tube Heat Exchanger with Field Synergy Principle
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The paper investigates the optimization analysis to the heat exchanger design, mainly with response surface method and genetic algorithm to explore the relationship between optimal fluid flow velocity and temperature of the heat exchanger using field synergy principle. First, finite volume method is proposed to calculate the flow temperature and flow rate distribution for numerical analysis. We identify the most suitable simulation equations by response surface methodology. Furthermore, a genetic algorithm approach is applied to optimize the relationship between fluid flow velocity and flow temperature of the heat exchanger. The results show that the field synergy angle plays vital role in the performance of a true heat exchanger.Keywords: optimization analysis, field synergy, heat exchanger, genetic algorithm
Procedia PDF Downloads 3072030 Analysis of Risk Factors Affecting the Motor Insurance Pricing with Generalized Linear Models
Authors: Puttharapong Sakulwaropas, Uraiwan Jaroengeratikun
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Casualty insurance business, the optimal premium pricing and adequate cost for an insurance company are important in risk management. Normally, the insurance pure premium can be determined by multiplying the claim frequency with the claim cost. The aim of this research was to study in the application of generalized linear models to select the risk factor for model of claim frequency and claim cost for estimating a pure premium. In this study, the data set was the claim of comprehensive motor insurance, which was provided by one of the insurance company in Thailand. The results of this study found that the risk factors significantly related to pure premium at the 0.05 level consisted of no claim bonus (NCB) and used of the car (Car code).Keywords: generalized linear models, risk factor, pure premium, regression model
Procedia PDF Downloads 4662029 Optimizing of Machining Parameters of Plastic Material Using Taguchi Method
Authors: Jumazulhisham Abdul Shukor, Mohd. Sazali Said, Roshanizah Harun, Shuib Husin, Ahmad Razlee Ab Kadir
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This paper applies Taguchi Optimization Method in determining the best machining parameters for pocket milling process on Polypropylene (PP) using CNC milling machine where the surface roughness is considered and the Carbide inserts cutting tool are used. Three machining parameters; speed, feed rate and depth of cut are investigated along three levels; low, medium and high of each parameter (Taguchi Orthogonal Arrays). The setting of machining parameters were determined by using Taguchi Method and the Signal-to-Noise (S/N) ratio are assessed to define the optimal levels and to predict the effect of surface roughness with assigned parameters based on L9. The final experimental outcomes are presented to prove the optimization parameters recommended by manufacturer are accurate.Keywords: inserts, milling process, signal-to-noise (S/N) ratio, surface roughness, Taguchi Optimization Method
Procedia PDF Downloads 6372028 Influence of Infrared Radiation on the Growth Rate of Microalgae Chlorella sorokiniana
Authors: Natalia Politaeva, Iuliia Smiatskaia, Iuliia Bazarnova, Iryna Atamaniuk, Kerstin Kuchta
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Nowadays, the progressive decrease of primary natural resources and ongoing upward trend in terms of energy demand, have resulted in development of new generation technological processes which are focused on step-wise production and residues utilization. Thus, microalgae-based 3rd generation bioeconomy is considered one of the most promising approaches that allow production of value-added products and sophisticated utilization of residues biomass. In comparison to conventional biomass, microalgae can be cultivated in wide range of conditions without compromising food and feed production, and thus, addressing issues associated with negative social and environmental impacts. However, one of the most challenging tasks is to undergo seasonal variations and to achieve optimal growing conditions for indoor closed systems that can cover further demand for material and energetic utilization of microalgae. For instance, outdoor cultivation in St. Petersburg (Russia) is only suitable within rather narrow time frame (from mid-May to mid-September). At earlier and later periods, insufficient sunlight and heat for the growth of microalgae were detected. On the other hand, without additional physical effects, the biomass increment in summer is 3-5 times per week, depending on the solar radiation and the ambient temperature. In order to increase biomass production, scientists from all over the world have proposed various technical solutions for cultivators and have been studying the influence of various physical factors affecting biomass growth namely: magnetic field, radiation impact, and electric field, etc. In this paper, the influence of infrared radiation (IR) and fluorescent light on the growth rate of microalgae Chlorella sorokiniana has been studied. The cultivation of Chlorella sorokiniana was carried out in 500 ml cylindrical glass vessels, which were constantly aerated. To accelerate the cultivation process, the mixture was stirred for 15 minutes at 500 rpm following 120 minutes of rest time. At the same time, the metabolic needs in nutrients were provided by the addition of micro- and macro-nutrients in the microalgae growing medium. Lighting was provided by fluorescent lamps with the intensity of 2500 ± 300 lx. The influence of IR was determined using IR lamps with a voltage of 220 V, power of 250 W, in order to achieve the intensity of 13 600 ± 500 lx. The obtained results show that under the influence of fluorescent lamps along with the combined effect of active aeration and variable mixing, the biomass increment on the 2nd day was three times, and on the 7th day, it was eight-fold. The growth rate of microalgae under the influence of IR radiation was lower and has reached 22.6·106 cells·mL-1. However, application of IR lamps for the biomass growth allows maintaining the optimal temperature of microalgae suspension at approximately 25-28°C, which might especially be beneficial during the cold season in extreme climate zones.Keywords: biomass, fluorescent lamp, infrared radiation, microalgae
Procedia PDF Downloads 1872027 Comparison between Continuous Genetic Algorithms and Particle Swarm Optimization for Distribution Network Reconfiguration
Authors: Linh Nguyen Tung, Anh Truong Viet, Nghien Nguyen Ba, Chuong Trinh Trong
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This paper proposes a reconfiguration methodology based on a continuous genetic algorithm (CGA) and particle swarm optimization (PSO) for minimizing active power loss and minimizing voltage deviation. Both algorithms are adapted using graph theory to generate feasible individuals, and the modified crossover is used for continuous variable of CGA. To demonstrate the performance and effectiveness of the proposed methods, a comparative analysis of CGA with PSO for network reconfiguration, on 33-node and 119-bus radial distribution system is presented. The simulation results have shown that both CGA and PSO can be used in the distribution network reconfiguration and CGA outperformed PSO with significant success rate in finding optimal distribution network configuration.Keywords: distribution network reconfiguration, particle swarm optimization, continuous genetic algorithm, power loss reduction, voltage deviation
Procedia PDF Downloads 1872026 A Model Predictive Control Based Virtual Active Power Filter Using V2G Technology
Authors: Mahdi Zolfaghari, Seyed Hossein Hosseinian, Hossein Askarian Abyaneh, Mehrdad Abedi
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This paper presents a virtual active power filter (VAPF) using vehicle to grid (V2G) technology to maintain power quality requirements. The optimal discrete operation of the power converter of electric vehicle (EV) is based on recognizing desired switching states using the model predictive control (MPC) algorithm. A fast dynamic response, lower total harmonic distortion (THD) and good reference tracking performance are realized through the presented control strategy. The simulation results using MATLAB/Simulink validate the effectiveness of the scheme in improving power quality as well as good dynamic response in power transferring capability.Keywords: electric vehicle, model predictive control, power quality, V2G technology, virtual active power filter
Procedia PDF Downloads 4302025 Students with Severe Learning Disabilities in Mainstream Classes: A Study of Comprehensions amongst School Staff and Parents Built on Observations and Interviews in a Phenomenological Framework
Authors: Inger Eriksson, Lisbeth Ohlsson, Jeremias Rosenqvist
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Ingress: Focus in the study is directed towards phenomena and concepts of segregation, integration, and inclusion of students attending a special school form in Sweden, namely compulsory school for pupils with learning disabilities (in Swedish 'särskola') as an alternative to mainstream compulsory school. Aim: The aim of the study is to examine the school situation for students attending särskola from a historical perspective focussing the 1980s, 1990s and the 21st century, from an integration perspective, and from a perspective of power. Procedure: Five sub-studies are reported, where integration and inclusion are looked into by observation studies and interviews with school leaders, teachers, special and remedial teachers, psychologists, coordinators, and parents in the special schools/särskola. In brief, the study about special school students attending mainstream classes from 1998 takes its point of departure in the idea that all knowledge development takes place in a social context. A special interest is taken in the school’s role for integration generally, and the role of special education particularly and on whose conditions the integration is taking place – the special school students' or the other students,' or may be equally, in the class. Pedagogical and social conditions for so called individually integrated special school students in elementary school classes were studied in eleven classes. Results: The findings are interpreted in a power perspective supported by Foucault and relationally by Vygotsky. The main part of the data consists of extensive descriptions of the eleven cases, here called integration situations. Conclusions: In summary, this study suggests that the possibilities for a special school student to get into the class community and fellowship and thereby be integrated with the class are to a high degree dependant on to what extent the student can take part in the pedagogical processes. The pedagogical situation for the special school student is affected not only by the class teacher and the support and measures undertaken but also by the other students in the class as they, in turn, are affected by how the special school student is acting. This mutual impact, which constitutes the integration process in itself, might result in a true integration if the special school student attains the status of being accepted on his/her own terms not only being cared for or cherished by some classmates. A special school student who is not accepted even on the terms of the class will often experience severe problems in the contacts with classmates and the school situation might thus be a mere placement.Keywords: integration/inclusion, mainstream school, power, special school students
Procedia PDF Downloads 2482024 Hydrogen Storage Systems for Enhanced Grid Balancing Services in Wind Energy Conversion Systems
Authors: Nezmin Kayedpour, Arash E. Samani, Siavash Asiaban, Jeroen M. De Kooning, Lieven Vandevelde, Guillaume Crevecoeur
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The growing adoption of renewable energy sources, such as wind power, in electricity generation is a significant step towards a sustainable and decarbonized future. However, the inherent intermittency and uncertainty of wind resources pose challenges to the reliable and stable operation of power grids. To address this, hydrogen storage systems have emerged as a promising and versatile technology to support grid balancing services in wind energy conversion systems. In this study, we propose a supplementary control design that enhances the performance of the hydrogen storage system by integrating wind turbine (WT) pitch and torque control systems. These control strategies aim to optimize the hydrogen production process, ensuring efficient utilization of wind energy while complying with grid requirements. The wind turbine pitch control system plays a crucial role in managing the turbine's aerodynamic performance. By adjusting the blade pitch angle, the turbine's rotational speed and power output can be regulated. Our proposed control design dynamically coordinates the pitch angle to match the wind turbine's power output with the optimal hydrogen production rate. This ensures that the electrolyzer receives a steady and optimal power supply, avoiding unnecessary strain on the system during high wind speeds and maximizing hydrogen production during low wind speeds. Moreover, the wind turbine torque control system is incorporated to facilitate efficient operation at varying wind speeds. The torque control system optimizes the energy capture from the wind while limiting mechanical stress on the turbine components. By harmonizing the torque control with hydrogen production requirements, the system maintains stable wind turbine operation, thereby enhancing the overall energy-to-hydrogen conversion efficiency. To enable grid-friendly operation, we introduce a cascaded controller that regulates the electrolyzer's electrical power-current in accordance with grid requirements. This controller ensures that the hydrogen production rate can be dynamically adjusted based on real-time grid demands, supporting grid balancing services effectively. By maintaining a close relationship between the wind turbine's power output and the electrolyzer's current, the hydrogen storage system can respond rapidly to grid fluctuations and contribute to enhanced grid stability. In this paper, we present a comprehensive analysis of the proposed supplementary control design's impact on the overall performance of the hydrogen storage system in wind energy conversion systems. Through detailed simulations and case studies, we assess the system's ability to provide grid balancing services, maximize wind energy utilization, and reduce greenhouse gas emissions.Keywords: active power control, electrolyzer, grid balancing services, wind energy conversion systems
Procedia PDF Downloads 842023 Integrated Location-Allocation Planning in Multi Product Multi Echelon Single Period Closed Loop Supply Chain Network Design
Authors: Santhosh Srinivasan, Vipul Garhiya, Shahul Hamid Khan
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Environmental performance along with social performance is becoming vital factors for industries to achieve global standards. With a good environmental policy global industries are differentiating them from their competitors. This paper concentrates on multi stage, multi product and multi period manufacturing network. Single objective mathematical models for a total cost for the entire forward supply chain and reverse chain are considered. Here five different problems are considered by varying the number of facilities for illustration. M-MOGA, Shuffle Frog Leaping algorithm (SFLA) and CPLEX are used for finding the optimal solution for the mathematical model.Keywords: closed loop supply chain, genetic algorithm, random search, multi period, green supply chain
Procedia PDF Downloads 3912022 Execution Time Optimization of Workflow Network with Activity Lead-Time
Authors: Xiaoping Qiu, Binci You, Yue Hu
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The executive time of the workflow network has an important effect on the efficiency of the business process. In this paper, the activity executive time is divided into the service time and the waiting time, then the lead time can be extracted from the waiting time. The executive time formulas of the three basic structures in the workflow network are deduced based on the activity lead time. Taken the process of e-commerce logistics as an example, insert appropriate lead time for key activities by using Petri net, and the executive time optimization model is built to minimize the waiting time with the time-cost constraints. Then the solution program-using VC++6.0 is compiled to get the optimal solution, which reduces the waiting time of key activities in the workflow, and verifies the role of lead time in the timeliness of e-commerce logistics.Keywords: electronic business, execution time, lead time, optimization model, petri net, time workflow network
Procedia PDF Downloads 1762021 Networked Implementation of Milling Stability Optimization with Bayesian Learning
Authors: Christoph Ramsauer, Jaydeep Karandikar, Tony Schmitz, Friedrich Bleicher
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Machining stability is an important limitation to discrete part machining. In this work, a networked implementation of milling stability optimization with Bayesian learning is presented. The milling process was monitored with a wireless sensory tool holder instrumented with an accelerometer at the Vienna University of Technology, Vienna, Austria. The recorded data from a milling test cut is used to classify the cut as stable or unstable based on the frequency analysis. The test cut result is fed to a Bayesian stability learning algorithm at the University of Tennessee, Knoxville, Tennessee, USA. The algorithm calculates the probability of stability as a function of axial depth of cut and spindle speed and recommends the parameters for the next test cut. The iterative process between two transatlantic locations repeats until convergence to a stable optimal process parameter set is achieved.Keywords: machining stability, machine learning, sensor, optimization
Procedia PDF Downloads 2062020 Jet-Stream Airsail: Study of the Shape and the Behavior of the Connecting Cable
Authors: Christopher Frank, Yoshiki Miyairi
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A jet-stream airsail concept takes advantage of aerology in order to fly without propulsion. Weather phenomena, especially jet streams, are relatively permanent high winds blowing from west to east, located at average altitudes and latitudes in both hemispheres. To continuously extract energy from the jet-stream, the system is composed of a propelled plane and a wind turbine interconnected by a cable. This work presents the aerodynamic characteristics and the behavior of the cable that links the two subsystems and transmits energy from the turbine to the aircraft. Two ways of solving this problem are explored: numerically and analytically. After obtaining the optimal shape of the cross-section of the cable, its behavior is analyzed as a 2D problem solved numerically and analytically. Finally, a 3D extension could be considered by adding lateral forces. The results of this work can be further used in the design process of the overall system: aircraft-turbine.Keywords: jet-stream, cable, tether, aerodynamics, aircraft, airsail, wind
Procedia PDF Downloads 3702019 Axial Flux Permanent Magnet Motor Design and Optimization by Using Artificial Neural Networks
Authors: Tugce Talay, Kadir Erkan
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In this study, the necessary steps for the design of axial flow permanent magnet motors are shown. The design and analysis of the engine were carried out based on ANSYS Maxwell program. The design parameters of the ANSYS Maxwell program and the artificial neural network system were established in MATLAB and the most efficient design parameters were found with the trained neural network. The results of the Maxwell program and the results of the artificial neural networks are compared and optimal working design parameters are found. The most efficient design parameters were submitted to the ANSYS Maxwell 3D design and the cogging torque was examined and design studies were carried out to reduce the cogging torque.Keywords: AFPM, ANSYS Maxwell, cogging torque, design optimisation, efficiency, NNTOOL
Procedia PDF Downloads 2202018 Inner and Outer School Contextual Factors Associated with Poor Performance of Grade 12 Students: A Case Study of an Underperforming High School in Mpumalanga, South Africa
Authors: Victoria L. Nkosi, Parvaneh Farhangpour
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Often a Grade 12 certificate is perceived as a passport to tertiary education and the minimum requirement to enter the world of work. In spite of its importance, many students do not make this milestone in South Africa. It is important to find out why so many students still fail in spite of transformation in the education system in the post-apartheid era. Given the complexity of education and its context, this study adopted a case study design to examine one historically underperforming high school in Bushbuckridge, Mpumalanga Province, South Africa in 2013. The aim was to gain a understanding of the inner and outer school contextual factors associated with the high failure rate among Grade 12 students. Government documents and reports were consulted to identify factors in the district and the village surrounding the school and a student survey was conducted to identify school, home and student factors. The randomly-sampled half of the population of Grade 12 students (53) participated in the survey and quantitative data are analyzed using descriptive statistical methods. The findings showed that a host of factors is at play. The school is located in a village within a municipality which has been one of the poorest three municipalities in South Africa and the lowest Grade 12 pass rate in the Mpumalanga province. Moreover, over half of the families of the students are single parents, 43% are unemployed and the majority has a low level of education. In addition, most families (83%) do not have basic study materials such as a dictionary, books, tables, and chairs. A significant number of students (70%) are over-aged (+19 years old); close to half of them (49%) are grade repeaters. The school itself lacks essential resources, namely computers, science laboratories, library, and enough furniture and textbooks. Moreover, teaching and learning are negatively affected by the teachers’ occasional absenteeism, inadequate lesson preparation, and poor communication skills. Overall, the continuous low performance of students in this school mirrors the vicious circle of multiple negative conditions present within and outside of the school. The complexity of factors associated with the underperformance of Grade 12 students in this school calls for a multi-dimensional intervention from government and stakeholders. One important intervention should be the placement of over-aged students and grade-repeaters in suitable educational institutions for the benefit of other students.Keywords: inner context, outer context, over-aged students, vicious cycle
Procedia PDF Downloads 2012017 Experimental Support for the District Metered Areas/Pressure Management Areas Application
Authors: K. Ilicic, D. Smoljan
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The purpose of the paper is to present and verify a methodology of decreasing water losses by introducing and managing District Metered Areas (DMA) and Pressure Management Areas (PMA) by analyzing the results of the application of the methodology to the water supply system of the city of Zagreb. Since it is a relatively large system that has been expanding rapidly, approach to addressing water losses was possible only by splitting the system to smaller flow and pressure zones. Besides, the geographical and technical limitations had imposed the necessity of high pressure in the system that needed to be reduced to the technically optimal level. Results of activities were monitored on a general and local level by establishing, monitoring, and controlling indicators that had been established by the International Water Association (IWA), among which the most recognizable were non-revenue water, water losses and real losses as presented in the paper.Keywords: district metered area, pressure metered area, active leakage control, water losses
Procedia PDF Downloads 1842016 High Strength Steel Thin-Walled Cold-Formed Profiles Manufactured for Automated Rack Supported Warehouses
Authors: A. Natali, F. V. Lippi, F. Morelli, W. Salvatore, J. H. M. De Paula Filho, P. Pol
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Automated Rack Supported Warehouses (ARSWs) are storage buildings whose load-bearing structure is made of the same steel racks where goods are stocked. These racks are made of cold formed elements, and the main supporting structure is repeated several times along the length of the building, resulting in a huge quantity of steel. The possibility of using high strength steel to manufacture the traditional cold-formed profiles used for ARSWs is numerically investigated, with the aim of reducing the necessary steel quantity but guaranteeing optimal structural performance levels.Keywords: steel racks, automated rack supported warehouse, thin-walled cold-formed elements, high strength steel, structural optimization
Procedia PDF Downloads 1572015 Design of Optimal Proportional Integral Derivative Attitude Controller for an Uncoupled Flexible Satellite Using Particle Swarm Optimization
Authors: Martha C. Orazulume, Jibril D. Jiya
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Flexible satellites are equipped with various appendages which vibrate under the influence of any excitation and make the attitude of the satellite to be unstable. Therefore, the system must be able to adjust to balance the effect of these appendages in order to point accurately and satisfactorily which is one of the most important problems in satellite design. Proportional Integral Derivative (PID) Controller is simple to design and computationally efficient to implement which is used to stabilize the effect of these flexible appendages. However, manual turning of the PID is time consuming, waste energy and money. Particle Swarm Optimization (PSO) is used to tune the parameters of PID Controller. Simulation results obtained show that PSO tuned PID Controller is able to re-orient the spacecraft attitude as well as dampen the effect of mechanical resonance and yields better performance when compared with manually tuned PID Controller.Keywords: Attitude Control, Flexible Satellite, Particle Swarm Optimization, PID Controller and Optimization
Procedia PDF Downloads 4012014 Flexible Design of Triboelectric Nanogenerators for Efficient Vibration Energy Harvesting
Authors: Meriam Khelifa
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In recent years, many studies have focused on the harvesting of the vibrations energy to produce electrical energy using contact separation (CS) triboelectric nanogenerators (TENG). The simplest design for a TENG consists of a capacitor comprising a single moving electrode. The conversion efficiency of vibration energy into electrical energy can, in principle, reach 100%. But to actually achieve this objective, it is necessary to optimize the parameters of the TENG, such as the dielectric constant and the thickness of the insulator, the load resistance, etc. In particular, the use of a switch which is actioned at optimal times within the TENG cycle is essential. Using numerical modeling and experimental design, we applied a methodology to find the TENG parameters which optimize the energy transfer efficiency (ETE) to almost 100% for any vibration frequency and amplitude. The rather simple design of a TENG is promising as an environment friendly device. It opens the doors for harvesting acoustic vibrations from the environment and to design effective protection against environmental noise.Keywords: vibrations, CS TENG, efficiency, design of experiments
Procedia PDF Downloads 902013 Multidisciplinarity, Interdisciplinarity and Transdisciplinarity in Peace Education and Peace Studies: A Content Analysis
Authors: Frances Bernard Kominkiewicz
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Demonstrating the ability to build social justice and peace is integral in undergraduate and graduate education. Many disciplines are involved in peace education and peace studies, and the collaboration of those disciplines are examined in this paper. To the author’s best knowledge, no content analysis research previously existed regarding peace studies and peace education from a multidisciplinarity, interdisciplinarity, and transdisciplinarity perspective. Peacebuilding is taught through these approaches, which adds to the depth, breadth, and richness of peace education and peace studies. This paper presents a content analysis of academic peace studies programs and course descriptions. Variables studied include contributions and foci of disciplines in peace studies programs and students’ engagement in community peacebuilding. The social work discipline, for example, focuses on social and economic justice as one of the nine competencies that undergraduate and graduate students must attain before earning a Bachelor of Social Work degree or a Master of Social Work degree and becoming social work practitioners. Demonstrating the ability to build social justice and peace is integral in social work education. Peacebuilding is taught through such social work courses as conflict resolution, and social work practice with communities and organizations, and these courses are examined in this research through multidisciplinarity, interdisciplinarity, and transdisciplinarity approach. Peace and social justice are linked terms in various fields, including social work. Social justice is of paramount importance in social work programs, and social workers are trained to advocate for human rights and social, economic, and environmental justice. Social workers use knowledge of oppression, globally as well as nationally, in the practice of peace education and peace studies. Social work is at the forefront in advocating for social justice as a discipline and joins with other educators in strengthening the peacebuilding opportunities for students. The content analysis, conducted through a random sample of peace studies and peace education university and college programs in the United States, found that although courses teach the concepts of peace education and peace studies, courses often are not given these titles in the social work discipline. Therefore, this analysis also includes a discussion of the multidisciplinarity, interdisciplinarity, and transdisciplinarity approach to peace education, peace studies, and peacebuilding and the importance of these approaches in educating students about peace. The content analysis further found great variability in the number of disciplines involved in peace studies programs, the focus of those disciplines in peace education, the placement of peace studies and peace education within the university or college, and the number of courses and concentrations available in peace studies and peace education. In conclusion, the research points toward very robust and diverse approaches to peace education with opportunities for further research and discussion.Keywords: content analysis, interdisciplinarity, multidisciplinarity, peace education programs
Procedia PDF Downloads 1552012 An Algorithm for Estimating the Stable Operation Conditions of the Synchronous Motor of the Ore Mill Electric Drive
Authors: M. Baghdasaryan, A. Sukiasyan
Abstract:
An algorithm for estimating the stable operation conditions of the synchronous motor of the ore mill electric drive is proposed. The stable operation conditions of the synchronous motor are revealed, taking into account the estimation of the q angle change and the technological factors. The stability condition obtained allows to ensure the stable operation of the motor in the synchronous mode, taking into account the nonlinear character of the mill loading. The developed algorithm gives an opportunity to present the undesirable phenomena, arising in the electric drive system. The obtained stability condition can be successfully applied for the optimal control of the electromechanical system of the mill.Keywords: electric drive, synchronous motor, ore mill, stability, technological factors
Procedia PDF Downloads 4252011 Optimization of Electrocoagulation Process Using Duelist Algorithm
Authors: Totok R. Biyanto, Arif T. Mardianto, M. Farid R. R., Luthfi Machmudi, kandi mulakasti
Abstract:
The main objective of this research is optimizing the electrocoagulation process design as a post-treatment for biologically vinasse effluent process. The first principle model with three independent variables that affect the energy consumption of electrocoagulation process i.e. current density, electrode distance, and time of treatment process are chosen as optimized variables. The process condition parameters were determined with the value of pH, electrical conductivity, and temperature of vinasse about 6.5, 28.5 mS/cm, 52 oC, respectively. Aluminum was chosen as the electrode material of electrocoagulation process. Duelist algorithm was used as optimization technique due to its capability to reach a global optimum. The optimization results show that the optimal process can be reached in the conditions of current density of 2.9976 A/m2, electrode distance of 1.5 cm and electrolysis time of 119 min. The optimized energy consumption during process is 34.02 Wh.Keywords: optimization, vinasse effluent, electrocoagulation, energy consumption
Procedia PDF Downloads 4692010 CRISPR-DT: Designing gRNAs for the CRISPR-Cpf1 System with Improved Target Efficiency and Specificity
Authors: Houxiang Zhu, Chun Liang
Abstract:
The CRISPR-Cpf1 system has been successfully applied in genome editing. However, target efficiency of the CRISPR-Cpf1 system varies among different gRNA sequences. The published CRISPR-Cpf1 gRNA data was reanalyzed. Many sequences and structural features of gRNAs (e.g., the position-specific nucleotide composition, position-nonspecific nucleotide composition, GC content, minimum free energy, and melting temperature) correlated with target efficiency were found. Using machine learning technology, a support vector machine (SVM) model was created to predict target efficiency for any given gRNAs. The first web service application, CRISPR-DT (CRISPR DNA Targeting), has been developed to help users design optimal gRNAs for the CRISPR-Cpf1 system by considering both target efficiency and specificity. CRISPR-DT will empower researchers in genome editing.Keywords: CRISPR-Cpf1, genome editing, target efficiency, target specificity
Procedia PDF Downloads 262