Search results for: nonlinear dynamic systems
1922 Milling Simulations with a 3-DOF Flexible Planar Robot
Authors: Hoai Nam Huynh, Edouard Rivière-Lorphèvre, Olivier Verlinden
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Manufacturing technologies are becoming continuously more diversified over the years. The increasing use of robots for various applications such as assembling, painting, welding has also affected the field of machining. Machining robots can deal with larger workspaces than conventional machine-tools at a lower cost and thus represent a very promising alternative for machining applications. Furthermore, their inherent structure ensures them a great flexibility of motion to reach any location on the workpiece with the desired orientation. Nevertheless, machining robots suffer from a lack of stiffness at their joints restricting their use to applications involving low cutting forces especially finishing operations. Vibratory instabilities may also happen while machining and deteriorate the precision leading to scrap parts. Some researchers are therefore concerned with the identification of optimal parameters in robotic machining. This paper continues the development of a virtual robotic machining simulator in order to find optimized cutting parameters in terms of depth of cut or feed per tooth for example. The simulation environment combines an in-house milling routine (DyStaMill) achieving the computation of cutting forces and material removal with an in-house multibody library (EasyDyn) which is used to build a dynamic model of a 3-DOF planar robot with flexible links. The position of the robot end-effector submitted to milling forces is controlled through an inverse kinematics scheme while controlling the position of its joints separately. Each joint is actuated through a servomotor for which the transfer function has been computed in order to tune the corresponding controller. The output results feature the evolution of the cutting forces when the robot structure is deformable or not and the tracking errors of the end-effector. Illustrations of the resulting machined surfaces are also presented. The consideration of the links flexibility has highlighted an increase of the cutting forces magnitude. This proof of concept will aim to enrich the database of results in robotic machining for potential improvements in production.Keywords: Control, machining, multibody, robotic, simulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13671921 Simulation Based Performance Comparison of Different Control Methods of ZSI Feeding Industrial Drives
Authors: Parag Nihawan, Ravinder Singh Bhatia, Dinesh Kumar Jain
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Industrial drives are source of serious power quality problems. In this, two typical industrial drives have been dealt with, namely, FOC induction motor drives and DTC induction motor drive. The Z-source inverter is an emerging topology of power electronic converters which is capable of buck boost characteristics. The performances of different control methods based Z-source inverters feeding these industrial drives have been investigated, in this work. The test systems have been modeled and simulated in MATLAB/SIMULINK. The results obtained after carrying out these simulations have been used to draw the conclusions.
Keywords: Z-Source Inverter, total harmonic distortion, direct torque control, field orientation control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10341920 Biocompatible Ionic Liquids in Liquid – Liquid Extraction of Lactic Acid: A Comparative Study
Authors: Konstantza Tonova, Ivan Svinyarov, Milen G. Bogdanov
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Ionic liquids consisting of a phosphonium cationic moiety and a saccharinate anion are synthesized and compared with their precursors, phosphonium chlorides, in reference to their extraction efficiency towards L-lactic acid. On the base of measurements of the acid and the water partitioning in the equilibrium biphasic systems, the molar ratios between acid, water and ionic liquid are estimated which allows to deduce the lactic acid extractive pathway. The effect of a salting-out addition that strengthens hydrophobicity in both phases is studied in view to reveal the best biphasic system with respect to IL low toxicity and high extraction efficiency.
Keywords: Biphasic system, Extraction, Ionic liquids, Lactic acid.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27161919 Toward an Architecture of a Component-Based System Supporting Separation of Non- Functional Concerns
Authors: Jerzy Nogiec, Kelley Trombly-Freytag, Shangping Ren
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The promises of component-based technology can only be fully realized when the system contains in its design a necessary level of separation of concerns. The authors propose to focus on the concerns that emerge throughout the life cycle of the system and use them as an architectural foundation for the design of a component-based framework. The proposed model comprises a set of superimposed views of the system describing its functional and non-functional concerns. This approach is illustrated by the design of a specific framework for data analysis and data acquisition and supplemented with experiences from using the systems developed with this framework at the Fermi National Accelerator Laboratory.Keywords: Distributed system, component-based technology, separation of concerns, software development, supervisory and control, QoS
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13361918 Realization of Electronically Tunable Current- Mode Multiphase Sinusoidal Oscillators Using CFTAs
Authors: Prungsak Uttaphut
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An implementation of current-mode multiphase sinusoidal oscillators is presented. Using CFTA-based lossy integrators, odd and odd/even phase systems can be realized with following advantages. The condition of oscillation and frequency of oscillation can be orthogonally tuned. The high output impedances facilitate easy driving an external load without additional current buffers. The proposed MSOs provide odd or even phase signals that are equally spaced in phase and equal amplitude. The circuit requires one CFTA, one resistor and one grounded capacitor per phase without additional current amplifier. The results of PSPICE simulations using CMOS CFTA are included to verify theory.
Keywords: multiphase sinusoidal oscillator, current-mode, CFTA, lossy integrator
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16151917 Optimal Voltage and Frequency Control of a Microgrid Using the Harmony Search Algorithm
Authors: Hossein Abbasi
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The stability is an important topic to plan and manage the energy in the microgrids as the same as the conventional power systems. The voltage and frequency stability is one of the most important issues recently studied in microgrids. The objectives of this paper are the modelling and designing of the components and optimal controllers for the voltage and frequency control of the AC/DC hybrid microgrid under the different disturbances. Since the PI controllers have the advantages of simple structure and easy implementation, so they are designed and modeled in this paper. The harmony search (HS) algorithm is used to optimize the controllers’ parameters. According to the achieved results, the PI controllers have a good performance in voltage and frequency control of the microgrid.
Keywords: Frequency control, HS algorithm, microgrid, PI controller, voltage control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13651916 Optical Wireless Sensor Networks Based on VLC with PLC-Ethernet Interface
Authors: Heejin Lee, Yeonjoo Kim, Kyungrak Sohn
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We present a white LED-based optical wireless communication systems for indoor ubiquitous sensor networks. Each sensor node could access to the server through the PLC (Power Line Communication)-Ethernet interface. The proposed system offers a full-duplex wireless link by using different wavelengths to reduce the inter-symbol interference between uplink and downlink. Through the 1-to-n optical wireless sensor network and PLC modem, the mobile terminals send a temperature data to server. The data transmission speed and distance are 115.2kbps and about 60cm, respectively.Keywords: Visible light communications, LED lighting, powerline communications, ubiquitous sensor networks, full-duplex links
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 37531915 Improvements in Navy Data Networks and Tactical Communication Systems
Authors: Laurent Enel, Franck Guillem
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This paper considers the benefits gained by using an efficient quality of service management such as DiffServ technique to improve the performance of military communications. Low delay and no blockage must be achieved especially for real time tactical data. All traffic flows generated by different applications do not need same bandwidth, same latency, same error ratio and this scalable technique of packet management based on priority levels is analysed. End to end architectures supporting various traffic flows and including lowbandwidth and high-delay HF or SHF military links as well as unprotected Internet sub domains are studied. A tuning of Diffserv parameters is proposed in accordance with different loads of various traffic and different operational situations.Keywords: Military data networks, Quality of service, Tacticalsystems.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20691914 A Preliminary Development of Virtual Sightseeing Website for Thai Temples on Rattanakosin Island
Authors: P. Jomsri
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Currently, the sources of cultures and tourist attractions are presented in online documentary form only. In order to make them more virtual, the researcher then collected and presented them in the form of Virtual Temple. The prototype, which is a replica of the actual location, was developed to the website and allows people who are interested in Rattanakosin Island can see in form of Panorama Pan View. By this way, anyone can access the data and appreciate the beauty of Rattanakosin Island in the virtual model like the real place.
The result from the experiment showed that the levels of the knowledge on Thai temples in Rattanakosin Island increased; moreover, the users were highly satisfied with the systems. It can be concluded that virtual temples can support to publicize Thai arts, cultures and travels, as well as it can be utilized effectively.
Keywords: Virtual sightseeing, rattanakosin island, Thai temples.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14741913 An Expert System Designed to Be Used with MOEAs for Efficient Portfolio Selection
Authors: K. Metaxiotis, K. Liagkouras
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This study presents an Expert System specially designed to be used with Multiobjective Evolutionary Algorithms (MOEAs) for the solution of the portfolio selection problem. The validation of the proposed hybrid System is done by using data sets from Hang Seng 31 in Hong Kong, DAX 100 in Germany and FTSE 100 in UK. The performance of the proposed system is assessed in comparison with the Non-dominated Sorting Genetic Algorithm II (NSGAII). The evaluation of the performance is based on different performance metrics that evaluate both the proximity of the solutions to the Pareto front and their dispersion on it. The results show that the proposed hybrid system is efficient for the solution of this kind of problems.
Keywords: Expert Systems, Multiobjective optimization, Evolutionary Algorithms, Portfolio Selection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17691912 Distributed Frequency Synchronization for Global Synchronization in Wireless Mesh Networks
Authors: Jung-Hyun Kim, Jihyung Kim, Kwangjae Lim, Dong Seung Kwon
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In this paper, our focus is to assure a global frequency synchronization in OFDMA-based wireless mesh networks with local information. To acquire the global synchronization in distributed manner, we propose a novel distributed frequency synchronization (DFS) method. DFS is a method that carrier frequencies of distributed nodes converge to a common value by repetitive estimation and averaging step and sharing step. Experimental results show that DFS achieves noteworthy better synchronization success probability than existing schemes in OFDMA-based mesh networks where the estimation error is presented.
Keywords: OFDMA systems, Frequency synchronization, Distributed networks, Multiple groups.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17191911 Disturbance Observer-Based Predictive Functional Critical Control of a Table Drive System
Authors: Toshiyuki Satoh, Hiroki Hara, Naoki Saito, Jun-ya Nagase, Norihiko Saga
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This paper addresses a control system design for a table drive system based on the disturbance observer (DOB)-based predictive functional critical control (PFCC). To empower the previously developed DOB-based PFC to handle constraints on controlled outputs, we propose to take a critical control approach. To this end, we derive the transfer function representation of the PFC controller and yield a detailed design procedure. The effectiveness of the proposed method is confirmed through an experimental evaluation.
Keywords: Critical control, disturbance observer, mechatronics, motion control, predictive functional control, table drive systems.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18771910 IntelligentLogger: A Heavy-Duty Vehicles Fleet Management System Based on IoT and Smart Prediction Techniques
Authors: D. Goustouridis, A. Sideris, I. Sdrolias, G. Loizos, N.-Alexander Tatlas, S. M. Potirakis
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Both daily and long-term management of a heavy-duty vehicles and construction machinery fleet is an extremely complicated and hard to solve issue. This is mainly due to the diversity of the fleet vehicles – machinery, which concerns not only the vehicle types, but also their age/efficiency, as well as the fleet volume, which is often of the order of hundreds or even thousands of vehicles/machineries. In the present paper we present “InteligentLogger”, a holistic heavy-duty fleet management system covering a wide range of diverse fleet vehicles. This is based on specifically designed hardware and software for the automated vehicle health status and operational cost monitoring, for smart maintenance. InteligentLogger is characterized by high adaptability that permits to be tailored to practically any heavy-duty vehicle/machinery (of different technologies -modern or legacy- and of dissimilar uses). Contrary to conventional logistic systems, which are characterized by raised operational costs and often errors, InteligentLogger provides a cost-effective and reliable integrated solution for the e-management and e-maintenance of the fleet members. The InteligentLogger system offers the following unique features that guarantee successful heavy-duty vehicles/machineries fleet management: (a) Recording and storage of operating data of motorized construction machinery, in a reliable way and in real time, using specifically designed Internet of Things (IoT) sensor nodes that communicate through the available network infrastructures, e.g., 3G/LTE; (b) Use on any machine, regardless of its age, in a universal way; (c) Flexibility and complete customization both in terms of data collection, integration with 3rd party systems, as well as in terms of processing and drawing conclusions; (d) Validation, error reporting & correction, as well as update of the system’s database; (e) Artificial intelligence (AI) software, for processing information in real time, identifying out-of-normal behavior and generating alerts; (f) A MicroStrategy based enterprise BI, for modeling information and producing reports, dashboards, and alerts focusing on vehicles– machinery optimal usage, as well as maintenance and scraping policies; (g) Modular structure that allows low implementation costs in the basic fully functional version, but offers scalability without requiring a complete system upgrade.
Keywords: E-maintenance, predictive maintenance, IoT sensor nodes, cost optimization, artificial intelligence, heavy-duty vehicles.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7701909 Optimal Operation of a Photovoltaic Induction Motor Drive Water Pumping System
Authors: Nelson K. Lujara
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The performance characteristics of a photovoltaic induction motor drive water pumping system with and without maximum power tracker is analyzed and presented. The analysis is done through determination and assessment of critical loss components in the system using computer aided design (CAD) tools for optimal operation of the system. The results can be used to formulate a well-calibrated computer aided design package of photovoltaic water pumping systems based on the induction motor drive. The results allow the design engineer to pre-determine the flow rate and efficiency of the system to suit particular application.
Keywords: Photovoltaic, water pumping, losses, induction motor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17471908 Determination the Curve Number Catchment by Using GIS and Remote Sensing
Authors: Abouzar Nasiri, Hamid Alipur
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In recent years, geographic information systems (GIS) and remote sensing using has increased to estimate runoff catchment. In this research, runoff curve number maps for captive catchment of Tehran by helping GIS and also remote sensing which based on factors such as vegetation, lands using, group of soil hydrology and hydrological conditions were obtained. Runoff curve numbers map was obtained by combining these maps in ARC GIS and SCS table. To evaluate the accuracy of the results, the maximum flow rate of flood which was obtained from curve numbers, was compared with the measured maximum flood rate at the watershed outlet and correctness of curve numbers were approved.
Keywords: Curve number, GIS, Remote sensing, Runoff.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 49791907 Embedded Singly Diagonally Implicit Runge-Kutta –Nystrom Method Order 5(4) for the Integration of Special Second Order ODEs
Authors: Fudziah Ismail
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In this paper a new embedded Singly Diagonally Implicit Runge-Kutta Nystrom fourth order in fifth order method for solving special second order initial value problems is derived. A standard set of test problems are tested upon and comparisons on the numerical results are made when the same set of test problems are reduced to first order systems and solved using the existing embedded diagonally implicit Runge-Kutta method. The results suggests the superiority of the new method.Keywords: Runge-Kutta Nystrom, Special second orderproblems.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16661906 Application of Advanced Oxidation Processes to Mefenamic Acid Elimination
Authors: Olga Gimeno, Javier Rivas, Angel Encinas, Fernando Beltran
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The elimimation of mefenamic acid has been carried out by photolysis, ozonation, adsorption onto activated carbon (AC) and combinations of the previous single systems (O3+AC and O3+UV). The results obtained indicate that mefenamic acid is not photo-reactive, showing a relatively low quantum yield of the order of 6 x 10-4 mol Einstein-1. Application of ozone to mefenamic aqueous solutions instantaneously eliminates the pharmaceutical, achieving simultaneously a 40% of mineralization. Addition of AC to the ozonation process does not enhance the process, moreover, mineralization is completely inhibited if compared to results obtained by single ozonation. The combination of ozone and UV radiation led to the best results in terms of mineralization (60% after 120 min).Keywords: Photolysis, mefenamic acid, ozone, activated carbon.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19651905 A New Robust Stability Criterion for Dynamical Neural Networks with Mixed Time Delays
Authors: Guang Zhou, Shouming Zhong
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In this paper, we investigate the problem of the existence, uniqueness and global asymptotic stability of the equilibrium point for a class of neural networks, the neutral system has mixed time delays and parameter uncertainties. Under the assumption that the activation functions are globally Lipschitz continuous, we drive a new criterion for the robust stability of a class of neural networks with time delays by utilizing the Lyapunov stability theorems and the Homomorphic mapping theorem. Numerical examples are given to illustrate the effectiveness and the advantage of the proposed main results.
Keywords: Neural networks, Delayed systems, Lyapunov function, Stability analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15841904 Comparing Emotion Recognition from Voice and Facial Data Using Time Invariant Features
Authors: Vesna Kirandziska, Nevena Ackovska, Ana Madevska Bogdanova
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The problem of emotion recognition is a challenging problem. It is still an open problem from the aspect of both intelligent systems and psychology. In this paper, both voice features and facial features are used for building an emotion recognition system. A Support Vector Machine classifiers are built by using raw data from video recordings. In this paper, the results obtained for the emotion recognition are given, and a discussion about the validity and the expressiveness of different emotions is presented. A comparison between the classifiers build from facial data only, voice data only and from the combination of both data is made here. The need for a better combination of the information from facial expression and voice data is argued.
Keywords: Emotion recognition, facial recognition, signal processing, machine learning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20181903 Matlab/Simulink Simulation of Solar Energy Storage System
Authors: Mustafa A. Al-Refai
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This paper investigates the energy storage technologies that can potentially enhance the use of solar energy. Water electrolysis systems are seen as the principal means of producing a large amount of hydrogen in the future. Starting from the analysis of the models of the system components, a complete simulation model was realized in the Matlab-Simulink environment. Results of the numerical simulations are provided. The operation of electrolysis and photovoltaic array combination is verified at various insulation levels. It is pointed out that solar cell arrays and electrolysers are producing the expected results with solar energy inputs that are continuously varying.
Keywords: Electrolyzer, Simulink, solar energy, storage system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 90761902 Artificial Neural Network based Web Application Firewall for SQL Injection
Authors: Asaad Moosa
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In recent years with the rapid development of Internet and the Web, more and more web applications have been deployed in many fields and organizations such as finance, military, and government. Together with that, hackers have found more subtle ways to attack web applications. According to international statistics, SQL Injection is one of the most popular vulnerabilities of web applications. The consequences of this type of attacks are quite dangerous, such as sensitive information could be stolen or authentication systems might be by-passed. To mitigate the situation, several techniques have been adopted. In this research, a security solution is proposed using Artificial Neural Network to protect web applications against this type of attacks. The solution has been experimented on sample datasets and has given promising result. The solution has also been developed in a prototypic web application firewall called ANNbWAF.
Keywords: Artificial Neural Networks ANN, SQL Injection, Web Application Firewall WAF, Web Application Scanner WAS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 56691901 The Hybrid Knowledge Model for Product Development Management
Authors: Heejung Lee, Hyo-Won Suh
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Hybrid knowledge model is suggested as an underlying framework for product development management. It can support such hybrid features as ontologies and rules. Effective collaboration in product development environment depends on sharing and reasoning product information as well as engineering knowledge. Many studies have considered product information and engineering knowledge. However, most previous research has focused either on building the ontology of product information or rule-based systems of engineering knowledge. This paper shows that F-logic based knowledge model can support such desirable features in a hybrid way.Keywords: Ontology, rule, F-logic, product development.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14751900 Study of Fast Etching of Silicon for the Fabrication of Bulk Micromachined MEMS Structures
Authors: V. Swarnalatha, A. V. Narasimha Rao, P. Pal
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The present research reports the investigation of fast etching of silicon for the fabrication of microelectromechanical systems (MEMS) structures using silicon wet bulk micromachining. Low concentration tetramethyl-ammonium hydroxide (TMAH) and hydroxylamine (NH2OH) are used as main etchant and additive, respectively. The concentration of NH2OH is varied to optimize the composition to achieve best etching characteristics such as high etch rate, significantly high undercutting at convex corner for the fast release of the microstructures from the substrate, and improved etched surface morphology. These etching characteristics are studied on Si{100} and Si{110} wafers as they are most widely used in the fabrication of MEMS structures as wells diode, transistors and integrated circuits.Keywords: KOH, MEMS, micromachining, silicon, TMAH, wet anisotropic etching.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12191899 Performance Boundaries for Interactive Finite Element Applications
Authors: Jaewon Jang, Gregory R. Miller
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This paper presents work characterizing finite element performance boundaries within which live, interactive finite element modeling is feasible on current and emerging systems. These results are based on wide-ranging tests performed using a prototype finite element program implemented specifically for this study, thereby enabling the unified investigation of numerous direct and iterative solver strategies and implementations in a variety of modeling contexts. The results are intended to be useful for researchers interested in interactive analysis by providing baseline performance estimates, to give guidance in matching solution strategies to problem domains, and to spur further work addressing the challenge of extending the present boundaries.Keywords: Finite Elements, Interactive Modeling, NumericalAnalysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13561898 Introduce the FWA in the Band 3300-3400 MHz
Authors: Lway F. Abdulrazak, Zaid A. Shamsan, Ali K. Aswad, Tharek Abd. Rahman
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This paper gives a study about forging solution to deploy the fixed wireless access (FWA) in the band 3300-3400MHz instead of 3400-3600MHz to eschew the harmful interference between from the FWA towards fixed satellite services receiver presented in this band. The impact of FWA services toward the FSS and the boundaries of spectrum emission mask had been considered to calculate the possible Guard band required in this case. In addition, supplementary separation distance added to improve the coexistence between the two adjacent bands. Simulation had been done using Matlab software base on ITU models reliance on the most popular specification used for the tropical weather countries. Review the current problem of interference between two systems and some mitigation techniques which adopted in Malaysia as a case study is a part of this research.Keywords: Coexistence, FSS, FWA, mask.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18141897 Model Predictive Control of Three Phase Inverter for PV Systems
Authors: Irtaza M. Syed, Kaamran Raahemifar
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This paper presents a model predictive control (MPC) of a utility interactive three phase inverter (TPI) for a photovoltaic (PV) system at commercial level. The proposed model uses phase locked loop (PLL) to synchronize the TPI with the power electric grid (PEG) and performs MPC control in a dq reference frame. TPI model consists of a boost converter (BC), maximum power point tracking (MPPT) control, and a three-leg voltage source inverter (VSI). The operational model of VSI is used to synthesize the sinusoidal current and track the reference. The model is validated using a 35.7 kW PV system in Matlab/Simulink. Implementation results show simplicity and accuracy, as well as reliability of the model.Keywords: Model predictive control, three phase voltage source inverter, PV system, Matlab/Simulink.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 37661896 Thermal Properties of Lime-Pozzolan Plasters for Application in Hollow Bricks Systems
Authors: Z. Pavlík, M. Čáchová, E. Vejmelková, T. Korecký, J. Fořt, M. Pavlíková, R. Černý
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The effect of waste ceramic powder on the thermal properties of lime-pozzolana composites is investigated. At first, the measurements of effective thermal conductivity of lime-pozzolan composites are performed in dependence on moisture content from the dry state to fully water saturated state using a pulse method. Then, the obtained data are analyzed using two different homogenization techniques, namely the Lichtenecker’s and Dobson’s formulas, taking into account Wiener’s and Hashin/Shtrikman bounds.
Keywords: Waste ceramic powder, lime-pozzolan plasters, effective thermal conductivity, homogenization techniques.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22611895 Operation Assay of an Industrial Single-Source – Single-Detector Gamma CT Using MCNP4C Code Simulation and Experimental Test Comparisons
Authors: M. Ghanadi, M. Rezazadeh*, M. Ardeshiri, R. Gholipour Peyvandi, M. Jafarzadeh, M. Shahriari, M.Rezaei Rad, Z. Gholamzadeh
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A 3D industrial computed tomography (CT) manufactured based on a first generation CT systems, single-source – single-detector, was evaluated. Operation accuracy assessment of the manufactured system was achieved using simulation in comparison with experimental tests. 137Cs and 60Co were used as a gamma source. Simulations were achieved using MCNP4C code. Experimental tests of 137Cs were in good agreement with the simulationsKeywords: Gamma source, Industrial CT, MCNP4C, Operation assessment
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16651894 Adoption of E-Business by Thai SMEs
Authors: Pisit Chanvarasuth
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The use of e-business in small and medium-sized enterprises (SMEs) has been recently received an enormous attention in information systems research by both academic and practitioners. With the adoption of new and efficient technologies to enhance businesses, Thai SMEs should be able to compete worldwide. Unfortunately, most of the owners are not used to new technologies. It is clear that most Thai SMEs prefer to work manually rather than electronically. This paper aims to provide a fundamental conceptual framework for E-business adoption by Thai SMEs. Rooted in Knowledge transfer model, several factors are identified, which drive and enable e-business adoption. By overlooking the benefits associated with implementing new technologies, it is difficult for Thai SMEs to perform well enough to compete globally. The paper also helps Thai SMEs to understand factors related to E-business adoption.Keywords: E-business, SME, Adoption, Knowledge Transfer, Thailand.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29631893 Information System Life Cycle: Applications in Construction and Manufacturing
Authors: Carlos J. Costa, Manuela Aparício
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In this paper, we present the information life cycle, and analyze the importance of managing the corporate application portfolio across this life cycle. The approach presented here does not correspond just to the extension of the traditional information system development life cycle. This approach is based in the generic life cycle employed in other contexts like manufacturing or marketing. In this paper it is proposed a model of an information system life cycle, supported in the assumption that a system has a limited life. But, this limited life may be extended. This model is also applied in several cases; being reported here two examples of the framework application in a construction enterprise, and in a manufacturing enterprise.
Keywords: Information systems/technology, informatio nsystems life cycle, organization engineering, information economics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1602