Search results for: electrical drive system
17815 Mooring Analysis of Duct-Type Tidal Current Power System in Shallow Water
Authors: Chul H. Jo, Do Y. Kim, Bong K. Cho, Myeong J. Kim
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The exhaustion of oil and the environmental pollution from the use of fossil fuel are increasing. Tidal current power (TCP) has been proposed as an alternative energy source because of its predictability and reliability. By applying a duct and single point mooring (SPM) system, a TCP device can amplify the generating power and keep its position properly. Because the generating power is proportional to cube of the current stream velocity, amplifying the current speed by applying a duct to a TCP system is an effective way to improve the efficiency of the power device. An SPM system can be applied at any water depth and is highly cost effective. Simple installation and maintenance procedures are also merits of an SPM system. In this study, we designed an SPM system for a duct-type TCP device for use in shallow water. Motions of the duct are investigated to obtain the response amplitude operator (RAO) as the magnitude of the transfer function. Parameters affecting the stability of the SPM system such as the fairlead departure angle, current velocity, and the number of clamp weights are analyzed and/or optimized. Wadam and OrcaFlex commercial software is used to design the mooring line.Keywords: mooring design, parametric analysis, RAO (Response Amplitude Operator), SPM (Single Point Mooring)
Procedia PDF Downloads 28917814 A Transform Domain Function Controlled VSSLMS Algorithm for Sparse System Identification
Authors: Cemil Turan, Mohammad Shukri Salman
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The convergence rate of the least-mean-square (LMS) algorithm deteriorates if the input signal to the filter is correlated. In a system identification problem, this convergence rate can be improved if the signal is white and/or if the system is sparse. We recently proposed a sparse transform domain LMS-type algorithm that uses a variable step-size for a sparse system identification. The proposed algorithm provided high performance even if the input signal is highly correlated. In this work, we investigate the performance of the proposed TD-LMS algorithm for a large number of filter tap which is also a critical issue for standard LMS algorithm. Additionally, the optimum value of the most important parameter is calculated for all experiments. Moreover, the convergence analysis of the proposed algorithm is provided. The performance of the proposed algorithm has been compared to different algorithms in a sparse system identification setting of different sparsity levels and different number of filter taps. Simulations have shown that the proposed algorithm has prominent performance compared to the other algorithms.Keywords: adaptive filtering, sparse system identification, TD-LMS algorithm, VSSLMS algorithm
Procedia PDF Downloads 36017813 Estimation of Carbon Losses in Rice: Wheat Cropping System of Punjab, Pakistan
Authors: Saeed Qaisrani
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The study was conducted to observe carbon and nutrient loss by burning of rice residues on rice-wheat cropping system The rice crop was harvested to conduct the experiment in a randomized complete block design (RCBD) with factors and 4 replications with a net plot size of 10 m x 20 m. Rice stubbles were managed by two methods i.e. Incorporation & burning of rice residues. Soil samples were taken to a depth of 30 cm before sowing & after harvesting of wheat. Wheat was sown after harvesting of rice by three practices i.e. Conventional tillage, Minimum tillage and Zero tillage to observe best tillage practices. Laboratory and field experiments were conducted on wheat to assess best tillage practice and residues management method with estimation of carbon losses. Data on the following parameters; establishment count, plant height, spike length, number of grains per spike, biological yield, fat content, carbohydrate content, protein content, and harvest index were recorded to check wheat quality & ensuring food security in the region. Soil physico-chemical analysis i.e. pH, electrical conductivity, organic matter, nitrogen, phosphorus, potassium, and carbon were done in soil fertility laboratory. Substantial results were found on growth, yield and related parameters of wheat crop. The collected data were examined statistically with economic analysis to estimate the cost-benefit ratio of using different tillage techniques and residue management practices. Obtained results depicted that Zero tillage method have positive impacts on growth, yield and quality of wheat, Moreover, it is cost effective methodology. Similarly, Incorporation is suitable and beneficial method for soil due to more nutrients provision and reduce the need of fertilizers. Burning of rice stubbles has negative impact including air pollution, nutrient loss, microbes died and carbon loss. Recommended the zero tillage technology to reduce carbon losses along with food security in Pakistan.Keywords: agricultural agronomy, food security, carbon sequestration, rice-wheat cropping system
Procedia PDF Downloads 27717812 Compromising of Vacuum Sewerage System in Developing Regions and the Impact on Environmet
Authors: Abdelsalam Elawwad, Mostafa Ragab, Hisham Abdel-Halim
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Leakage in sewerage system can cause groundwater and soil contamination in urban areas, especially in area with a high groundwater table. This is a serious problem in small villages in developing countries that rely on ground water as a source for irrigation and drinking purposes. In the developed countries, the recent trend in areas with low population densities is vacuum sewerage system, which is environmentally safer than conventional gravity system, protecting public health, preventing exfiltration to the ground water, very easily applied in a relatively short time and can cope with a faster expansion of the urbanized areas. The aim of this work is to assess the feasibility of using vacuum sewerage in developing country, such as Egypt. Knowledge of local conditions can determine the most suitable sewer system for a specific region. Technical, environmental and financial comparisons between conventional sewerage system and vacuum sewerage system were held using statistical analysis. Different conditions, such as population densities, geometry of area, and ground water depths were evaluated. Sample comprising of 30 Egyptian villages was selected, where a complete design for conventional sewerage system and vacuum sewerage system was done. Based on this study, it is recommended from the environmental point of view to construct the vacuum sewerage system in such villages with low population densities; however, it is not economic for all cases. From financial point of view, vacuum sewerage system was a good competitor to conventional systems in flat areas and areas with high groundwater table. The local market supplying of the construction equipment especially collection chambers will greatly affect the investment cost. Capacity building and social mobilization will also play a great role in sustainability of this system. At the end, it is noteworthy that environmental sustainability and public health are more important than the financial aspects.Keywords: ground water, conventional system, vacuum system, statistics, cost, density, terrain
Procedia PDF Downloads 27517811 Leading to Attract, Retain, Motivate, Inspire your Employees to Peak Performance
Authors: David Suson
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In today's work environment, it becomes harder and harder to attract top talent, motivate them to achieve your goals, create a collaborative work environment and then retain them. It is especially challenging when you have remote employees, manage virtually, have different personalities, ages, work ethics and especially when there is a lure of better opportunities elsewhere. Leaders want results. All the strategies and tactics in the world won't make a difference if your people don't execute and "follow you into battle". The key to better leadership is motivating your teams to want to execute, want to work harder, want to work as a team, all while improving morale. Anyone can force employees by threatening them. This session teaches a 180-degree approach. Objectives/Outcomes: 1. Learn the 3 ways this leadership approach differs from traditional leadership, 2. Use a simple process to increase engagement and loyalty, 3. Implement strategies to drive performance. The approach being taught inspires, motivates, engages, and helps to attract better employees.Keywords: leadership, success, communication, skills
Procedia PDF Downloads 13417810 Application of Fractional Model Predictive Control to Thermal System
Authors: Aymen Rhouma, Khaled Hcheichi, Sami Hafsi
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The article presents an application of Fractional Model Predictive Control (FMPC) to a fractional order thermal system using Controlled Auto Regressive Integrated Moving Average (CARIMA) model obtained by discretization of a continuous fractional differential equation. Moreover, the output deviation approach is exploited to design the K -step ahead output predictor, and the corresponding control law is obtained by solving a quadratic cost function. Experiment results onto a thermal system are presented to emphasize the performances and the effectiveness of the proposed predictive controller.Keywords: fractional model predictive control, fractional order systems, thermal system, predictive control
Procedia PDF Downloads 41117809 An Automatic Speech Recognition Tool for the Filipino Language Using the HTK System
Authors: John Lorenzo Bautista, Yoon-Joong Kim
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This paper presents the development of a Filipino speech recognition tool using the HTK System. The system was trained from a subset of the Filipino Speech Corpus developed by the DSP Laboratory of the University of the Philippines-Diliman. The speech corpus was both used in training and testing the system by estimating the parameters for phonetic HMM-based (Hidden-Markov Model) acoustic models. Experiments on different mixture-weights were incorporated in the study. The phoneme-level word-based recognition of a 5-state HMM resulted in an average accuracy rate of 80.13 for a single-Gaussian mixture model, 81.13 after implementing a phoneme-alignment, and 87.19 for the increased Gaussian-mixture weight model. The highest accuracy rate of 88.70% was obtained from a 5-state model with 6 Gaussian mixtures.Keywords: Filipino language, Hidden Markov Model, HTK system, speech recognition
Procedia PDF Downloads 48017808 Computer Network Applications, Practical Implementations and Structural Control System Representations
Authors: El Miloudi Djelloul
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The computer network play an important position for practical implementations of the differently system. To implement a system into network above all is needed to know all the configurations, which is responsible to be a part of the system, and to give adequate information and solution in realtime. So if want to implement this system for example in the school or relevant institutions, the first step is to analyze the types of model which is needed to be configured and another important step is to organize the works in the context of devices, as a part of the general system. Often before configuration, as important point is descriptions and documentations from all the works into the respective process, and then to organize in the aspect of problem-solving. The computer network as critic infrastructure is very specific so the paper present the effectiveness solutions in the structured aspect viewed from one side, and another side is, than the paper reflect the positive aspect in the context of modeling and block schema presentations as an better alternative to solve the specific problem because of continually distortions of the system from the line of devices, programs and signals or packed collisions, which are in movement from one computer node to another nodes.Keywords: local area networks, LANs, block schema presentations, computer network system, computer node, critical infrastructure packed collisions, structural control system representations, computer network, implementations, modeling structural representations, companies, computers, context, control systems, internet, software
Procedia PDF Downloads 36517807 Signaling Using Phase Shifting in Wi-Fi Backscatter System
Authors: Chang-Bin Ha, Young-Min Ko, Seongjoo Lee, Hyoung-Kyu Song
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In this paper, the signaling scheme using phase shifting is proposed for the improved performance of the Wi-Fi backscatter system. Because the communication in the Wi-Fi backscatter system is based on on-off modulation and impedance modulation by unit of packet, the data rate is very low compared to the conventional wireless systems. Also, because the Wi-Fi backscatter system is based on the RF-powered device, the achievement of high reliability is difficult. In order to increase the low data rate, the proposed scheme transmits information of multiple bits during one packet period. Also, in order to increase the reliability, the proposed scheme shifts the phase of signal in according to the transmitting information. The simulation result shows that the proposed scheme has the improved throughput performance.Keywords: phase shifting, RF-powered device, Wi-Fi backscatter system, IoT
Procedia PDF Downloads 44217806 A Simplified Model of the Control System with PFM
Authors: Bekmurza H. Aitchanov, Sholpan K. Aitchanova, Olimzhon A. Baimuratov, Aitkul N. Aldibekova
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This work considers the automated control system (ACS) of milk quality during its magnetic field processing. For achieving high level of quality control methods were applied transformation of complex nonlinear systems in a linearized system with a less complex structure. Presented ACS is adjustable by seven parameters: mass fraction of fat, mass fraction of dry skim milk residues (DSMR), density, mass fraction of added water, temperature, mass fraction of protein, acidity.Keywords: fluids magnetization, nuclear magnetic resonance, automated control system, dynamic pulse-frequency modulator, PFM, nonlinear systems, structural model
Procedia PDF Downloads 37517805 Robust Stabilization against Unknown Consensus Network
Authors: Myung-Gon Yoon, Jung-Ho Moon, Tae Kwon Ha
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This paper considers a robust stabilization problem of a single agent in a multi-agent consensus system composed of identical agents, when the network topology of the system is completely unknown. It is shown that the transfer function of an agent in a consensus system can be described as a multiplicative perturbation of the isolated agent transfer function in frequency domain. Applying known robust stabilization results, we present sufficient conditions for a robust stabilization of an agent against unknown network topology.Keywords: single agent control, multi-agent system, transfer function, graph angle
Procedia PDF Downloads 45217804 An Intelligent Nondestructive Testing System of Ultrasonic Infrared Thermal Imaging Based on Embedded Linux
Authors: Hao Mi, Ming Yang, Tian-yue Yang
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Ultrasonic infrared nondestructive testing is a kind of testing method with high speed, accuracy and localization. However, there are still some problems, such as the detection requires manual real-time field judgment, the methods of result storage and viewing are still primitive. An intelligent non-destructive detection system based on embedded linux is put forward in this paper. The hardware part of the detection system is based on the ARM (Advanced Reduced Instruction Set Computer Machine) core and an embedded linux system is built to realize image processing and defect detection of thermal images. The CLAHE algorithm and the Butterworth filter are used to process the thermal image, and then the boa server and CGI (Common Gateway Interface) technology are used to transmit the test results to the display terminal through the network for real-time monitoring and remote monitoring. The system also liberates labor and eliminates the obstacle of manual judgment. According to the experiment result, the system provides a convenient and quick solution for industrial non-destructive testing.Keywords: remote monitoring, non-destructive testing, embedded Linux system, image processing
Procedia PDF Downloads 22417803 The Factors that Effect to User Satisfaction of Information System in Bangkok Hospital
Authors: Somchai Buaroong
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This research attempted to study information system success in dimensions of the user satisfaction level and to find the association between the independent factors of the user experiences, user knowledge, and user attitude. The study sample was selected using simple random sampling that comprised of 190 users who had used the Bangkok HIS. The data were reported from 165 questionnaires. The results found that the user satisfaction was at a moderate level, user satisfaction on the information quality and system quality was at a moderate level, while satisfaction on service quality was at a high level. The computer knowledge of the user was at a moderate level, and the user attitude was at a positive level. The participation of the user was at a low level and the participation in decision and in evaluation was at a low level; however participation in implementation and in benefit was at a moderate.Keywords: information system success, hospital information system, user attitude, user satisfaction
Procedia PDF Downloads 32017802 Does "R and D" Investment Drive Economic Growth? Evidence from Africa
Authors: Boopen Seetanah, R. V. Sannassee, Sheereen Fauzel, Robin Nunkoo
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The bulk of research on the impact of research and development (R&D) has been carried out in developed economies where the intensity of R&D expenditure has been relatively high and stable for many years. However, there is a paucity of similar studies in developing countries. In this paper, we provide empirical estimates of the impact of R&D investment on economic growth in a developing African economy (Mauritius) where R&D expenditure intensity has been low initially, but rising, albeit moderately in recent years. Using a dynamic time series analysis over the period 1980 to 2014 in a Vector Autoregressive framework, R & D is shown to have a positive and significant effect on the economic progress of the island, although the impact is considerably less when compared to both other ingredients of growth and also to reported elasticities fromdeveloped economies . Interestingly, there is evidence of bicausality between R & D and growth. furthermore, R & D positively impacts on both domestic and foreign investment, suggesting the possibilities of indirect effects.Keywords: R & D, VECM, Africa, Mauritius
Procedia PDF Downloads 43817801 Patterns of Positive Feedback Formation in the System of Online Action
Authors: D. Gvozdikov
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The purpose of this study is an attempt to describe an online action as a system that combines disjointed events and behavioral chains into a whole. The research focuses on patterns of naturally-formed chains of actions united by an orientation towards the online environment. A key characteristic of the system of online action is that it acts as an attractor for separate actions and chains of behavioral repertoire accumulating time and efforts made by users. The article demonstrates how the chains of online-offline actions are combined into a single pattern due to a simple identifiable mechanism, a positive feedback system. Using methods of digital ethnography and analyzing the content of the Instagram application and media blogs, the research reveals how through the positive feedback mechanism the entire system of online action acquires stability and can expand involving new spheres of human activity.Keywords: digital anthropology, internet studies, systems theory, social media
Procedia PDF Downloads 13317800 Advanced Hybrid Particle Swarm Optimization for Congestion and Power Loss Reduction in Distribution Networks with High Distributed Generation Penetration through Network Reconfiguration
Authors: C. Iraklis, G. Evmiridis, A. Iraklis
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Renewable energy sources and distributed power generation units already have an important role in electrical power generation. A mixture of different technologies penetrating the electrical grid, adds complexity in the management of distribution networks. High penetration of distributed power generation units creates node over-voltages, huge power losses, unreliable power management, reverse power flow and congestion. This paper presents an optimization algorithm capable of reducing congestion and power losses, both described as a function of weighted sum. Two factors that describe congestion are being proposed. An upgraded selective particle swarm optimization algorithm (SPSO) is used as a solution tool focusing on the technique of network reconfiguration. The upgraded SPSO algorithm is achieved with the addition of a heuristic algorithm specializing in reduction of power losses, with several scenarios being tested. Results show significant improvement in minimization of losses and congestion while achieving very small calculation times.Keywords: congestion, distribution networks, loss reduction, particle swarm optimization, smart grid
Procedia PDF Downloads 44517799 Defining a Holistic Approach for Model-Based System Engineering: Paradigm and Modeling Requirements
Authors: Hycham Aboutaleb, Bruno Monsuez
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Current systems complexity has reached a degree that requires addressing conception and design issues while taking into account all the necessary aspects. Therefore, one of the main challenges is the way complex systems are specified and designed. The exponential growing effort, cost and time investment of complex systems in modeling phase emphasize the need for a paradigm, a framework and a environment to handle the system model complexity. For that, it is necessary to understand the expectations of the human user of the model and his limits. This paper presents a generic framework for designing complex systems, highlights the requirements a system model needs to fulfill to meet human user expectations, and defines the refined functional as well as non functional requirements modeling tools needs to meet to be useful in model-based system engineering.Keywords: system modeling, modeling language, modeling requirements, framework
Procedia PDF Downloads 53117798 Low Cost Real Time Robust Identification of Impulsive Signals
Authors: R. Biondi, G. Dys, G. Ferone, T. Renard, M. Zysman
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This paper describes an automated implementable system for impulsive signals detection and recognition. The system uses a Digital Signal Processing device for the detection and identification process. Here the system analyses the signals in real time in order to produce a particular response if needed. The system analyses the signals in real time in order to produce a specific output if needed. Detection is achieved through normalizing the inputs and comparing the read signals to a dynamic threshold and thus avoiding detections linked to loud or fluctuating environing noise. Identification is done through neuronal network algorithms. As a setup our system can receive signals to “learn” certain patterns. Through “learning” the system can recognize signals faster, inducing flexibility to new patterns similar to those known. Sound is captured through a simple jack input, and could be changed for an enhanced recording surface such as a wide-area recorder. Furthermore a communication module can be added to the apparatus to send alerts to another interface if needed.Keywords: sound detection, impulsive signal, background noise, neural network
Procedia PDF Downloads 31917797 Simulation with Uncertainties of Active Controlled Vibration Isolation System for Astronaut’s Exercise Platform
Authors: Shield B. Lin, Ziraguen O. Williams
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In a task to assist NASA in analyzing the dynamic forces caused by operational countermeasures of an astronaut’s exercise platform impacting the spacecraft, an active proportional-integral-derivative controller commanding a linear actuator is proposed in a vibration isolation system to regulate the movement of the exercise platform. Computer simulation shows promising results that most exciter forces can be reduced or even eliminated. This paper emphasizes on parameter uncertainties, variations and exciter force variations. Drift and variations of system parameters in the vibration isolation system for astronaut’s exercise platform are analyzed. An active controlled scheme is applied with the goals to reduce the platform displacement and to minimize the force being transmitted to the spacecraft structure. The controller must be robust enough to accommodate the wide variations of system parameters and exciter forces. Computer simulation for the vibration isolation system was performed via MATLAB/Simulink and Trick. The simulation results demonstrate the achievement of force reduction with small platform displacement under wide ranges of variations in system parameters.Keywords: control, counterweight, isolation, vibration
Procedia PDF Downloads 14617796 Multi-Agent System for Irrigation Using Fuzzy Logic Algorithm and Open Platform Communication Data Access
Authors: T. Wanyama, B. Far
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Automatic irrigation systems usually conveniently protect landscape investment. While conventional irrigation systems are known to be inefficient, automated ones have the potential to optimize water usage. In fact, there is a new generation of irrigation systems that are smart in the sense that they monitor the weather, soil conditions, evaporation and plant water use, and automatically adjust the irrigation schedule. In this paper, we present an agent based smart irrigation system. The agents are built using a mix of commercial off the shelf software, including MATLAB, Microsoft Excel and KEPServer Ex5 OPC server, and custom written code. The Irrigation Scheduler Agent uses fuzzy logic to integrate the information that affect the irrigation schedule. In addition, the Multi-Agent system uses Open Platform Connectivity (OPC) technology to share data. OPC technology enables the Irrigation Scheduler Agent to communicate over the Internet, making the system scalable to a municipal or regional agent based water monitoring, management, and optimization system. Finally, this paper presents simulation and pilot installation test result that show the operational effectiveness of our system.Keywords: community water usage, fuzzy logic, irrigation, multi-agent system
Procedia PDF Downloads 29817795 Alignment of Information System Strategy and Green Information System Strategy: Comprehension and A Review of the Literature
Authors: Wartika Memed Purawinata, Kridanto Surendro, Husni Sastramiharja, Iping Supriana S.
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The information system is one of the contributors to environmental degradation and pollution are known to be released, such as the increasing of use of IT equipment and energy consumption , life cycles of IT equipment are getting shorter, IT equipment waste disposal and so on, therefore the information system should have a role in related environmental issues. Organization need to develop the ability of green to minimize negative impacts on the environment. Although the green information system is an important topic, many organizations fail to manage the environment in a way that is adequate because they ignore aspect of strategy. Alignment strategy is very important to ensure that all people do the activities of the organization headed in the same direction. Alignment strategy helps organization, determine which is more important for organization, and then make road mad to achieve the organization goal. Therefore, this paper discusses the review of the alignment, information systems strategy, and IS green strategy. With this discussion is expected there is an understanding about the alignment of information systems strategy and strategy of green IS, and its relationship with the achievement of business goals that have commitment to reduce the negative impact of information systems on the environment.Keywords: alignment, strategy, information system, green
Procedia PDF Downloads 45617794 Modeling Intelligent Threats: Case of Continuous Attacks on a Specific Target
Authors: Asma Ben Yaghlane, Mohamed Naceur Azaiez
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In this paper, we treat a model that falls in the area of protecting targeted systems from intelligent threats including terrorism. We introduce the concept of system survivability, in the context of continuous attacks, as the probability that a system under attack will continue operation up to some fixed time t. We define a constant attack rate (CAR) process as an attack on a targeted system that follows an exponential distribution. We consider the superposition of several CAR processes. From the attacker side, we determine the optimal attack strategy that minimizes the system survivability. We also determine the optimal strengthening strategy that maximizes the system survivability under limited defensive resources. We use operations research techniques to identify optimal strategies of each antagonist. Our results may be used as interesting starting points to develop realistic protection strategies against intentional attacks.Keywords: CAR processes, defense/attack strategies, exponential failure, survivability
Procedia PDF Downloads 39517793 Phytoremediation Rates of Water Hyacinth in an Aquaculture Effluent Hydroponic System
Authors: E. A. Kiridi, A. O. Ogunlela
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Conventional wastewater treatment plants of activated carbon, electrodialysis, ion exchange, reverse osmosis etc. are expensive to install, operate and maintain especially in developing countries; therefore, the use of aquatic macrophytes for wastewater purification is a viable alternative. On the first day of experimentation, approximately 100g of water hyacinth was introduced into the hydroponic units in four replicates. The water quality parameters measured were total suspended solids (TSS), pH and electrical conductivity (EC). Others were concentration of ammonium–nitrogen (NH4+-N), nitrite-nitrogen (NO2--N), nitrate-nitrogen (NO3--N), phosphate–phosphorus (PO43--P), and biomass value. At phytoremediation intervals of 7, 14, 21 and 28 days, the biomass recorded were 438.2 g, 600.7 g, 688.2 g and 725.7 g. Water hyacinth was able to reduce the pollutant concentration of all the selected parameter. The percentage reduction of pH ranged from 1.9% to 14.7%, EC from 49.8% to 97.0%, TDS from 50.4% to 97.6%, TSS from 34.0% to 78.3%, NH4+-N from 38.9% to 85.2%, NO2--N from 0% to 84.6%, NO3--N from 63.2% to 98.8% and PO43--P from 10% to 88.0%. Paired sample t-test shows that at 95% confidence level, it can be concluded statistically that the inequality between the pre-treatment and post-treatment values are significant. This suggests that the use of water hyacinth is valuable in the design and operation of aquaculture effluent treatment and should therefore be adopted by environmental and wastewater managers.Keywords: aquaculture effluent, phytoremediation, pollutant, water hyacinth
Procedia PDF Downloads 27317792 A Broadband Tri-Cantilever Vibration Energy Harvester with Magnetic Oscillator
Authors: Xiaobo Rui, Zhoumo Zeng, Yibo Li
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A novel tri-cantilever energy harvester with magnetic oscillator was presented, which could convert the ambient vibration into electrical energy to power the low-power devices such as wireless sensor networks. The most common way to harvest vibration energy is based on the use of linear resonant devices such as cantilever beam, since this structure creates the highest strain for a given force. The highest efficiency will be achieved when the resonance frequency of the harvester matches the vibration frequency. The limitation of the structure is the narrow effective bandwidth. To overcome this limitation, this article introduces a broadband tri-cantilever harvester with nonlinear stiffness. This energy harvester typically consists of three thin cantilever beams vertically arranged with Neodymium Magnets ( NdFeB)magnetics at its free end and a fixed base at the other end. The three cantilevers have different resonant frequencies by designed in different thicknesses. It is obviously that a similar advantage of multiple resonant frequencies as piezoelectric cantilevers array structure is built. To achieve broadband energy harvesting, magnetic interaction is used to introduce the nonlinear system stiffness to tune the resonant frequency to match the excitation. Since the three cantilever tips are all free and the magnetic force is distance dependent, the resonant frequencies will be complexly changed with the vertical vibration of the free end. Both model and experiment are built. The electromechanically coupled lumped-parameter model is presented. An electromechanical formulation and analytical expressions for the coupled nonlinear vibration response and voltage response are given. The entire structure is fabricated and mechanically attached to a electromagnetic shaker as a vibrating body via the fixed base, in order to couple the vibrations to the cantilever. The cantilevers are bonded with piezoelectric macro-fiber composite (MFC) materials (Model: M8514P2). The size of the cantilevers is 120*20mm2 and the thicknesses are separately 1mm, 0.8mm, 0.6mm. The prototype generator has a measured performance of 160.98 mW effective electrical power and 7.93 DC output voltage via the excitation level of 10m/s2. The 130% increase in the operating bandwidth is achieved. This device is promising to support low-power devices, peer-to-peer wireless nodes, and small-scale wireless sensor networks in ambient vibration environment.Keywords: tri-cantilever, ambient vibration, energy harvesting, magnetic oscillator
Procedia PDF Downloads 15417791 Smart Grids in Morocco: An Outline of the Recent Developments, Key Drivers, and Recommendations for Better Implementation
Authors: Mohamed Laamim, Abdelilah Rochd, Aboubakr Benazzouz, Abderrahim El Fadili
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Smart grids have recently sparked a lot of interest in the energy sector as they allow for the modernization and digitization of the existing power infrastructure. Smart grids have several advantages in terms of reducing the environmental impact of generating power from fossil fuels due to their capacity to integrate large amounts of distributed energy resources. On the other hand, smart grid technologies necessitate many field investigations and requirements. This paper focuses on the major difficulties that governments face around the world and compares them to the situation in Morocco. Also presented in this study are the current works and projects being developed to improve the penetration of smart grid technologies into the electrical system. Furthermore, the findings of this study will be useful to promote the smart grid revolution in Morocco, as well as to construct a strong foundation and develop future needs for better penetration of technologies that aid in the integration of smart grid features.Keywords: smart grids, microgrids, virtual power plants, digital twin, distributed energy resources, vehicle-to-grid, advanced metering infrastructure.
Procedia PDF Downloads 14017790 Design and Analysis of 1.4 MW Hybrid Saps System for Rural Electrification in Off-Grid Applications
Authors: Arpan Dwivedi, Yogesh Pahariya
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In this paper, optimal design of hybrid standalone power supply system (SAPS) is done for off grid applications in remote areas where transmission of power is difficult. The hybrid SAPS system uses two primary energy sources, wind and solar, and in addition to these diesel generator is also connected to meet the load demand in case of failure of wind and solar system. This paper presents mathematical modeling of 1.4 MW hybrid SAPS system for rural electrification. This paper firstly focuses on mathematical modeling of PV module connected in a string, secondly focuses on modeling of permanent magnet wind turbine generator (PMWTG). The hybrid controller is also designed for selection of power from the source available as per the load demand. The power output of hybrid SAPS system is analyzed for meeting load demands at urban as well as for rural areas.Keywords: SAPS, DG, PMWTG, rural area, off-grid, PV module
Procedia PDF Downloads 24917789 Proposed Anticipating Learning Classifier System for Cloud Intrusion Detection (ALCS-CID)
Authors: Wafa' Slaibi Alsharafat
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Cloud computing is a modern approach in network environment. According to increased number of network users and online systems, there is a need to help these systems to be away from unauthorized resource access and detect any attempts for privacy contravention. For that purpose, Intrusion Detection System is an effective security mechanism to detect any attempts of attacks for cloud resources and their information. In this paper, Cloud Intrusion Detection System has been proposed in term of reducing or eliminating any attacks. This model concerns about achieving high detection rate after conducting a set of experiments using benchmarks dataset called KDD'99.Keywords: IDS, cloud computing, anticipating classifier system, intrusion detection
Procedia PDF Downloads 47417788 The Effect of Computer-Based Formative Assessment on Learning Outcome
Authors: Van Thien NGO
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The purpose of the study is to examine the effect of student response systems in computer-based formative assessment on learning outcomes. The backward design course is a tool to be applied for collecting necessary assessment evidence. The quasi-experimental research design involves collecting pre and posttest data on students assigned to the control group and the experimental group. The sample group consists of 150 college students randomly selected from two of the eight classes of electrical and electronics students at Cao Thang Technical College in Ho Chi Minh City, Vietnam. Findings from this research revealed that the experimental group, in which student response systems were applied, got better results than the controlled group, who did not apply them. Results show that using student response systems for technology-based formative assessment is vital and meaningful not only for teachers but also for students in the teaching and learning process.Keywords: student response system, computer-based formative assessment, learning outcome, backward design course
Procedia PDF Downloads 13317787 Impact of Financial System’s Development on Economic Development: An Empirical Investigation
Authors: Vilma Deltuvaitė
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Comparisons of financial development across countries are central to answering many of the questions on factors leading to economic development. For this reason this study analyzes the implications of financial system’s development on country’s economic development. The aim of the article: to analyze the impact of financial system’s development on economic development. The following research methods were used: systemic, logical and comparative analysis of scientific literature, analysis of statistical data, time series model (Autoregressive Distributed Lag (ARDL) Model). The empirical results suggest about positive short and long term effect of stock market development on GDP per capita.Keywords: banking sector, economic development, financial system’s development, stock market, private bond market
Procedia PDF Downloads 38617786 Optimal Replacement Period for a One-Unit System with Double Repair Cost Limits
Authors: Min-Tsai Lai, Taqwa Hariguna
Abstract:
This paper presents a periodical replacement model for a system, considering the concept of single and cumulative repair cost limits simultaneously. The failures are divided into two types. Minor failure can be corrected by minimal repair and serious failure makes the system breakdown completely. When a minor failure occurs, if the repair cost is less than a single repair cost limit L1 and the accumulated repair cost is less than a cumulative repair cost limit L2, then minimal repair is executed, otherwise, the system is preventively replaced. The system is also replaced at time T or at serious failure. The optimal period T minimizing the long-run expected cost per unit time is verified to be finite and unique under some specific conditions.Keywords: repair-cost limit, cumulative repair-cost limit, minimal repair, periodical replacement policy
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