Search results for: load testing
1425 Induction of alpha-Amylase in Wheat Grain Cultivars as an Indicator of Resistance to Pre-harvest Sprouting
Authors: Aidar A. Khakimzhanov, Vladimir A. Kuzovlev, Nurgul S. Mamytova, Dinara A. Shansharova, Oleg V. Fursov
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The influence of humidity and low temperature on the α- amylase activity and isoenzyme composition of grains of different wheat varieties have been studied. The identified samples of varieties have significant difference in the level of enzyme induction under the impact of high humidity and low temperature. It is proposed to use this methodological approach for testing genotypes and wheat breeding lines for resistance to pre-harvest sprouting (PHS).
Keywords: α-Amylase, isoenzymes, wheat, pre-harvest sprouting.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18521424 Fuzzy Control of a Three Phase ThyristorizedInduction Motor
Authors: Abolfazl Jalilvand, Mohammad Reza Feyzi, Sohrab Khanmohammad, Mohammad Bagher Bana Sharifian, Ali Sajjadi
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Nowadays the control of stator voltage at a constant frequency is one of the traditional and low expense methods in order to control the speed of induction motors near its nominal speed. The torque of induction motor is a nonlinear function of the firing angle, phase angle and speed. In this paper the speed control of induction motor regarding various load torque and under different conditions will be investigated based on a fuzzy controller with inverse training.
Keywords: Three phase induction motor, AC converter, speedcontrol, fuzzy control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17971423 Lumped Parameter Models for Numerical Simulation of the Dynamic Response of Hoisting Appliances
Authors: Giovanni Incerti, Luigi Solazzi, Candida Petrogalli
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This paper describes three lumped parameters models for the study of the dynamic behavior of a boom crane. The models here proposed allows to evaluate the fluctuations of the load arising from the rope and structure elasticity and from the type of the motion command imposed by the winch. A calculation software was developed in order to determine the actual acceleration of the lifted mass and the dynamic overload during the lifting phase. Some application examples are presented, with the aim of showing the correlation between the magnitude of the stress and the type of the employed motion command.Keywords: Crane, dynamic model, overloading condition, vibration.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19641422 Measurement of Systemic Power Efficiency of Microwave Heating Application
Authors: Yi He, Nutdechatorn Puangngernmak, Suramate Chalermwisutkul
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Microwave heating process has been developed about sixty years while measurement system has also progressed. Because of irradiation of high frequency of microwave, researchers have been utilized many costly technical instrument measuring parameters to evaluate the performance of microwave heating system. Therefore, this paper is intended to present an easier and feasible efficiency measurement method. It can help inspecting efficiency of microwave heating system with good accuracy, while the method can also give reference to optimizing procedure for microwave heating system for various load material
Keywords: measurement, microwave heating system, systemic power efficiency
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18471421 Proposal of Solidification/Stabilisation Process of Chosen Hazardous Waste by Cementation
Authors: Bozena Dohnalkova
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This paper presents a part of the project solving which is dedicated to the identification of the hazardous waste with the most critical production within the Czech Republic with the aim to study and find the optimal composition of the cement matrix that will ensure maximum content disposal of chosen hazardous waste. In the first stage of project solving – which represents this paper – a specific hazardous waste was chosen, its properties were identified and suitable solidification agents were chosen. Consequently solidification formulas and testing methodology was proposed.
Keywords: Cementation, solidification, waste, binder.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18671420 Pilot Scale Production and Compatibility Criteria of New Self-Cleaning Materials
Authors: J. Ranogajec, O. Rudic, S. Pasalic, S. Vucetic, D. Cjepa
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The paper involves a chain of activities from synthesis, establishment of the methodology for characterization and testing of novel protective materials through the pilot production and application on model supports. It summarizes the results regarding the development of the pilot production protocol for newly developed self-cleaning materials. The optimization of the production parameters was completed in order to improve the most important functional properties (mineralogy characteristics, particle size, self-cleaning properties and photocatalytic activity) of the newly designed nanocomposite material.
Keywords: Cultural heritage. Materials compatibility. Pilot production. Self-cleaning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23181419 Sensitivity Analysis of Real-Time Systems
Authors: Benjamin Gorry, Andrew Ireland, Peter King
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Verification of real-time software systems can be expensive in terms of time and resources. Testing is the main method of proving correctness but has been shown to be a long and time consuming process. Everyday engineers are usually unwilling to adopt formal approaches to correctness because of the overhead associated with developing their knowledge of such techniques. Performance modelling techniques allow systems to be evaluated with respect to timing constraints. This paper describes PARTES, a framework which guides the extraction of performance models from programs written in an annotated subset of C.Keywords: Performance Modelling, Real-time, SensitivityAnalysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15131418 Some Factors Affecting the Compressive Behaviour of Structural Masonry at Small Scales
Authors: A. Mohammed, T. G. Hughes
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This paper presents part of a research into the small scale modelling of masonry. Small scale testing of masonry has been carried out by many authors, but few have attempted a systematic determination of the parameters that affect masonry at a small scale. The effect of increasing mortar strength and different sand gradings under compression were investigated. The results show masonry strength at small scale is influenced by increasing mortar strength and different sand gradings.Keywords: Compression, masonry, models, mortar, sand gradings
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25451417 Injection Forging of Splines Using Numerical and Experimental Study
Authors: M.Zadshakoyan, H.Jafarzadeh, E.Abdi Sobbouhi
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Injection forging is a Nett-shape manufacturing process in which one or two punches move axially causing a radial flow into a die cavity in a form which is prescribed by the exitgeometry, such as pulley, flanges, gears and splines on a shaft. This paper presents an experimental and numerical study of the injection forging of splines in terms of load requirement and material flow. Three dimensional finite element analyses are used to investigate the effect of some important parameters in this process. The experiment has been carried out using solid commercial lead billets with two different billet diameters and four different dies.Keywords: Injection forging, splines, material flow, FEM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17751416 A Failure Analysis Tool for HDD Analysis
Authors: C. Kumjeera, T. Unchim, B. Marungsri, A. Oonsivilai
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The study of piezoelectric material in the past was in T-Domain form; however, no one has studied piezoelectric material in the S-Domain form. This paper will present the piezoelectric material in the transfer function or S-Domain model. S-Domain is a well known mathematical model, used for analyzing the stability of the material and determining the stability limits. By using S-Domain in testing stability of piezoelectric material, it will provide a new tool for the scientific world to study this material in various forms.
Keywords: Hard disk drive, failure analysis, tool, time
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27511415 Performance Evaluation of Routing Protocols For High Density Ad Hoc Networks based on Qos by GlomoSim Simulator
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Ad hoc networks are characterized by multihop wireless connectivity, frequently changing network topology and the need for efficient dynamic routing protocols. We compare the performance of three routing protocols for mobile ad hoc networks: Dynamic Source Routing (DSR) , Ad Hoc On-Demand Distance Vector Routing (AODV), location-aided routing(LAR1).The performance differentials are analyzed using varying network load, mobility, and network size. We simulate protocols with GLOMOSIM simulator. Based on the observations, we make recommendations about when the performance of either protocol can be best.Keywords: Ad hoc Network , Glomosim , routing protocols.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16191414 Parallelization and Optimization of SIFT Feature Extraction on Cluster System
Authors: Mingling Zheng, Zhenlong Song, Ke Xu, Hengzhu Liu
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Scale Invariant Feature Transform (SIFT) has been widely applied, but extracting SIFT feature is complicated and time-consuming. In this paper, to meet the demand of the real-time applications, SIFT is parallelized and optimized on cluster system, which is named pSIFT. Redundancy storage and communication are used for boundary data to improve the performance, and before representation of feature descriptor, data reallocation is adopted to keep load balance in pSIFT. Experimental results show that pSIFT achieves good speedup and scalability.Keywords: cluster, image matching, parallelization and optimization, SIFT.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18631413 The Benefits of Regional Brand for Companies
Authors: H. Starzyczna, M. Stoklasa, K. Matusinska
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This article deals with the benefits of regional brands for companies in the Czech Republic. Research was focused on finding out the expected and actual benefits of regional brands for companies. The data were obtained by questionnaire survey and analysed by IBM SPSS. Representative sample of 204 companies was created. The research analysis disclosed the expected benefits that the regional brand should bring to companies. But the actual benefits are much worse. The statistical testing of hypotheses revealed that the benefits depend on the region of origin, which surprised both us and the regional coordinators.
Keywords: Brand, regional brands, product protective branding programs, brand benefits.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14601412 Connected Objects with Optical Rectenna for Wireless Information Systems
Authors: Chayma Bahar, Chokri Baccouch, Hedi Sakli, Nizar Sakli
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Harvesting and transport of optical and radiofrequency signals are a topical subject with multiple challenges. In this paper, we present a Optical RECTENNA system. We propose here a hybrid system solar cell antenna for 5G mobile communications networks. Thus, we propose rectifying circuit. A parametric study is done to follow the influence of load resistance and input power on Optical RECTENNA system performance. Thus, we propose a solar cell antenna structure in the frequency band of future 5G standard in 2.45 GHz bands.Keywords: Antenna, Rectenna, solar cell, 5G, optical RECTENNA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4841411 Modeling and Simulation of Switched Reluctance Motor with Three-Phase and Four- Phase Configurations
Authors: Abdolamir Nekoubin
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The reluctance motor is an electric motor in which torque is produced by the tendency of its moveable part to move to a position where the inductance of the excited winding is maximized. In this paper switched reluctance motors (SRMs) with two different configurations(3-phase SRM with 4rotor poles and 6 stator poles, 4- phase SRM with 6rotor poles and 8 stator poles) is designed by RMxprt, and performance of them is analyzed. Efficiency and torque of SRM for different configurations in full-load condition have been presented. The results indicate that with correct choosing of motor applications, maximum efficiency can be found.Keywords: reluctance motor, maximum efficiency, rotor
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29021410 The Influence of Social Network Websites on Level of user Satisfaction
Authors: Pedram Behyar, Maryam Heidari, Zahra Bayat
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the purpose of this research is to identify and clarify factors which have positive effect among user satisfaction and their social networking through websites. The examined factors in this research are; innovation, ease of use, trustworthy and customer support which are defined as satisfaction factors. To obtain reliable research approaches and to have better result in this research four hypothesizes used to test. This hypothesis testing has been done by correlation, regression and test of normality by using “SPSS16" also the data which was analyzed by this software. this data was gathered from prepaid questionnaire.Keywords: Customer Satisfaction, Social Network Website
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18581409 Sensory Acceptability of Novel Sorrel/Roselle (Hibiscus sabdariffa L.)
Authors: Tamara Anderson, Neela Badrie
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Consumers are demanding novel beverages that are healthier, convenient and have appealing consumer acceptance. The objectives of this study were to investigate the effects of adding grape polyphenols and the influence of presenting health claims on the sensory acceptability of wines. Fresh red sorrel calyces were fermented into wines. The total soluble solids of the pectinase-treated sorrel puree were from 4°Brix to 23.8°Brix. Polyphenol in the form of grape pomace extract was added to sorrel wines (w/v) in specified levels to give 0. 25. 50 and 75 ppm. A focus group comprising of 12 panelists was use to select the level of polyphenol to be added to sorrel wines for sensory preference The sensory attributed of the wines which were evaluated were colour, clarity, aroma, flavor, mouth-feel, sweetness, astringency and overall preference. The sorrel wine which was most preferred from focus group evaluation was presented for hedonic rating. In the first stage of hedonic testing, the sorrel wine was served chilled at 7°C for 24 h prior to sensory evaluation. Each panelist was provided with a questionnaire and was asked to rate the wines on colour, aroma, flavor, mouth-feel, sweetness, astringency and overall acceptability using a 9-point hedonic scale. In the second stage of hedonic testing, the panelist were instructed to read a health abstract on the health benefits of polyphenolic compounds and again to rate sorrel wine with added 25 ppm polyphenol. Paired t-test was used for the analysis of the influence of presenting health information on polyphenols on hedonic scoring of sorrel wines. Focus groups found that the addition of polyphenol addition had no significant effect on sensory color and aroma but affected clarity and flavor. A 25 ppm wine was liked moderately in overall acceptability. The presentation of information on the health benefit of polyphenols in sorrel wines to panelists had no significant influence on the sensory acceptance of wine. More than half of panelists would drink this wine now and then. This wine had color L 19.86±0.68, chroma 2.10±0.12, hue° 16.90 ±3.10 and alcohol content of 13.0%. The sorrel wine was liked moderately in overall acceptability with the added polyphenols.Keywords: Sorrel wines, Roselle Hibiscus sabdariffa L, novel wine, polyphenols, health benefits, physicochemical properties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23531408 Dynamic Study on the Evaluation of the Settlement of Soil under Sea Dam
Authors: Faroudja Meziani, Amar Kahil
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In order to study the variation in settlement of soil under a dyke dam, the modelisation in our study consists of applying an imposed displacement at the base of the mass of soil (consisting of a saturated sand). The imposed displacement follows the evolution of acceleration of the earthquake of Boumerdes 2003 in Algeria. Moreover, the gravity load is taken into consideration by taking account the specific weight of the materials constituting the dyke. The results obtained show that the gravity loads have a direct influence on the evolution of settlement, especially at the center of the dyke where these loads are higher.
Keywords: Settlement, dynamic analysis, rockfill dam, effect of earthquake, soil dynamics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7871407 Effect of Composition on Work Hardening Coefficient of Bismuth-Lead Binary Alloy
Authors: K. A. Mistry, I. B. Patel, A. H. Prajapati
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In the present work, the alloy of Bismuth-lead is prepared on the basis of percentage of molecular weight 9:1, 5:5 and 1:9 ratios and grown by Zone- Refining Technique under a vacuum atmosphere. The EDAX of these samples are done and the results are reported. Micro hardness test has been used as an alternative test for measuring material’s tensile properties. The effect of temperature and load on the hardness of the grown alloy has been studied. Further the comparative studies of work hardening coefficients are reported.
Keywords: EDAX, hardening coefficient, Micro hardness, Bi-Pb alloy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19441406 Influence of Deficient Materials on the Reliability of Reinforced Concrete Members
Authors: Sami W. Tabsh
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The strength of reinforced concrete depends on the member dimensions and material properties. The properties of concrete and steel materials are not constant but random variables. The variability of concrete strength is due to batching errors, variations in mixing, cement quality uncertainties, differences in the degree of compaction and disparity in curing. Similarly, the variability of steel strength is attributed to the manufacturing process, rolling conditions, characteristics of base material, uncertainties in chemical composition, and the microstructure-property relationships. To account for such uncertainties, codes of practice for reinforced concrete design impose resistance factors to ensure structural reliability over the useful life of the structure. In this investigation, the effects of reductions in concrete and reinforcing steel strengths from the nominal values, beyond those accounted for in the structural design codes, on the structural reliability are assessed. The considered limit states are flexure, shear and axial compression based on the ACI 318-11 structural concrete building code. Structural safety is measured in terms of a reliability index. Probabilistic resistance and load models are compiled from the available literature. The study showed that there is a wide variation in the reliability index for reinforced concrete members designed for flexure, shear or axial compression, especially when the live-to-dead load ratio is low. Furthermore, variations in concrete strength have minor effect on the reliability of beams in flexure, moderate effect on the reliability of beams in shear, and sever effect on the reliability of columns in axial compression. On the other hand, changes in steel yield strength have great effect on the reliability of beams in flexure, moderate effect on the reliability of beams in shear, and mild effect on the reliability of columns in axial compression. Based on the outcome, it can be concluded that the reliability of beams is sensitive to changes in the yield strength of the steel reinforcement, whereas the reliability of columns is sensitive to variations in the concrete strength. Since the embedded target reliability in structural design codes results in lower structural safety in beams than in columns, large reductions in material strengths compromise the structural safety of beams much more than they affect columns.
Keywords: Code, flexure, limit states, random variables, reinforced concrete, reliability, reliability index, shear, structural safety.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25841405 A Study on the Relation of Corporate Governance and Pricing for Initial Public Offerings
Authors: Chei-Chang Chiou, Sen-Wei Wang, Yu-Min Wang
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The purpose of this study is to investigate the relationship between corporate governance and pricing for initial public offerings (IPOs). Empirical result finds that the prediction of pricing of IPOs with corporate governance added can have a rather higher degree of predicting accuracy than that of non governance added during the training and testing samples. Therefore, it can be observed that corporate governance mechanism can affect the pricing of IPOsKeywords: Artificial neural networks, corporate governance, initial public offerings.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18061404 Peak-to-Average Power Ratio Reduction in OFDM Systems using Huffman Coding
Authors: Ashraf A. Eltholth, Adel R. Mikhail, A. Elshirbini, Moawad I. Moawad, A. I. Abdelfattah
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In this paper we proposed the use of Huffman coding to reduce the PAR of an OFDM system as a distortionless scrambling technique, and we utilize the amount saved in the total bit rate by the Huffman coding to send the encoding table for accurate decoding at the receiver without reducing the effective throughput. We found that the use of Huffman coding reduces the PAR by about 6 dB. Also we have investigated the effect of PAR reduction due to Huffman coding through testing the spectral spreading and the inband distortion due to HPA with different IBO values. We found a complete match of our expectation from the proposed solution with the obtained simulation results.Keywords: HPA, Huffman coding, OFDM, PAR
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25971403 Synthesis, Characterization and PL Properties of Cds Nanoparticles Confined within a Functionalized SBA-15 Mesoprous
Authors: Azam Anaraki Firooz, Ali Reza Mahjoub, Reza Donyaei Ziba
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A simple and dexterous in situ method was introduced to load CdS nanocrystals into organofunctionalized mesoporous, which used an ion-exchange method. The products were extensively characterized by combined spectroscopic methods. X- ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) demonstrated both the maintenance of pore symmetry (space group p6mm) of SBA-15 and the presence of CdS nanocrystals with uniform sizes of about 6 - 8 nm inside the functionalized SBA-15 channels. These mesoporous silica-supported CdS composites showed room temperature photoluminescence properties with a blue shift, indicating the quantum size effect of nanocrystalline CdS.
Keywords: Semiconductors, luminescence, mesoporous material, CdS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16361402 C-LNRD: A Cross-Layered Neighbor Route Discovery for Effective Packet Communication in Wireless Sensor Network
Authors: K. Kalaikumar, E. Baburaj
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One of the problems to be addressed in wireless sensor networks is the issues related to cross layer communication. Cross layer architecture shares the information across the layer, ensuring Quality of Services (QoS). With this shared information, MAC protocol adapts effective functionality maintenance such as route selection on changeable sensor network environment. However, time slot assignment and neighbour route selection time duration for cross layer have not been carried out. The time varying physical layer communication over cross layer causes high traffic load in the sensor network. Though, the traffic load was reduced using cross layer optimization procedure, the computational cost is high. To improve communication efficacy in the sensor network, a self-determined time slot based Cross-Layered Neighbour Route Discovery (C-LNRD) method is presented in this paper. In the presented work, the initial process is to discover the route in the sensor network using Dynamic Source Routing based Medium Access Control (MAC) sub layers. This process considers MAC layer operation with dynamic route neighbour table discovery. Then, the discovered route path for packet communication employs Broad Route Distributed Time Slot Assignment method on Cross-Layered Sensor Network system. Broad Route means time slotting on varying length of the route paths. During packet communication in this sensor network, transmission of packets is adjusted over the different time with varying ranges for controlling the traffic rate. Finally, Rayleigh fading model is developed in C-LNRD to identify the performance of the sensor network communication structure. The main task of Rayleigh Fading is to measure the power level of each communication under MAC sub layer. The minimized power level helps to easily reduce the computational cost of packet communication in the sensor network. Experiments are conducted on factors such as power factor, on packet communication, neighbour route discovery time, and information (i.e., packet) propagation speed.
Keywords: Medium access control, neighbour route discovery, wireless sensor network, Rayleigh fading, distributed time slot assignment
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7741401 Transfer Function of Piezoelectric Material
Authors: C. Worakitjaroenphon, A. Oonsivilai
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The study of piezoelectric material in the past was in T-Domain form; however, no one has studied piezoelectric material in the S-Domain form. This paper will present the piezoelectric material in the transfer function or S-Domain model. S-Domain is a well known mathematical model, used for analyzing the stability of the material and determining the stability limits. By using S-Domain in testing stability of piezoelectric material, it will provide a new tool for the scientific world to study this material in various forms.Keywords: Piezoelectric, Stability, S-Domain, Transfer function
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 38661400 Distribution Voltage Regulation Under Three- Phase Fault by Using D-STATCOM
Authors: Chaiyut Sumpavakup, Thanatchai Kulworawanichpong
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This paper presents the voltage regulation scheme of D-STATCOM under three-phase faults. It consists of the voltage detection and voltage regulation schemes in the 0dq reference. The proposed control strategy uses the proportional controller in which the proportional gain, kp, is appropriately adjusted by using genetic algorithms. To verify its use, a simplified 4-bus test system is situated by assuming a three-phase fault at bus 4. As a result, the DSTATCOM can resume the load voltage to the desired level within 1.8 ms. This confirms that the proposed voltage regulation scheme performs well under three-phase fault events.Keywords: D-STATCOM, proportional controller, genetic algorithms.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17901399 Sustainable Upgrade of Existing Heritage Infrastructure: Strengthening and Rehabilitation of the LH Ford Bridge
Authors: Vince Scolaro, Lakshman Prasad, Ted Polley, Sanjivan Deshpande
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The LH Ford Bridge, built in the 1960’s, comprises 28 spans, is 800 m long and crosses the Macquarie River at Dubbo, NSW. The main bridge spans comprise three spans with a 63 m centre span (25 m drop-in section) supported by halving joints from the main cantilevers and back spans of 28 m. The main bridge spans were built using complex construction staging (first of this type in NSW). They comprise twin precast boxes, in-situ reinforced concrete infills, and cantilevered outriggers stressed both longitudinally and transversely. Since construction, this bridge has undergone significantly increased design vehicle loads and showed signs of excessive shrinkage and creep leading to significant sagging of the centre span with evidence of previous failure and remediation of the halving joints. A comprehensive load rating assessment was undertaken taking account of the original complex construction staging. Deficiencies identified included, inadequate capacity of the halving joints, failure of the bearings at the halving joints, inadequate shear capacity of the girder webs and inadequate girder flexural capacity to carry B-Double design vehicles. A strengthening system comprising two new piers (under each of the halving joints), new bearings and installation of external prestressing to the soffit of both drop-in-span and back spans was adopted. A portion of dead load had to be transferred from the superstructure to the new piers via innovative soft/stiff bearing combinations to reduce new locked in stresses resulting from the new pier supports. Significant temporary works comprised a precast concrete shell beam forming the pile cap/pier structure, addition of temporary suspended scaffold (without overstressing the existing superstructure) and installation of jacking stays for new bearing top and bottom plates. This paper presents how this existing historic and socially important bridge was strengthened and updated to increase its design life without the need for replacement.
Keywords: Strengthening, creep, construction, box girder.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 801398 Design of OTA with Common Drain and Folded Cascade Used in ADC
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In this report, an OTA which is used in fully differential pipelined ADC was described. Using gain-boost architecture with difference-ended amplifier, this OTA achieve high-gain and high-speed. Besides, the CMFB circuit is also used, and some methods are concerned to improve the performance. Then, by optimization the layout design, OTA-s mismatch was reduced. This design was using TSMC 0.18um CMOS process and simulation both schematic and layout in Cadence. The result of the simulation shows that the OTA has a gain up to 80dB,a unity gain bandwidth of about 1.437GHz for a 2pF load, a slew rate is about 428V/μs, a output swing is 0.2V~1.35V, with the power supply of 1.8V, the power consumption is 88mW. This amplifier was used in a 10bit 150MHz pipelined ADC.Keywords: OTA, common drain, CMFB, pipelined ADC
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33331397 Mechanical Buckling of Engesser-Timoshenko Beams with a Pair of Piezoelectric Layers
Authors: A. R. Nezamabadi, M. Karami Khorramabadi
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This paper presents the elastic buckling of homogeneous beams with a pair of piezoelectric layers surface bonded on both sides of the beams. The displacement field of beam is assumed based on the Engesser-Timoshenko beam theory. Applying the Hamilton's principle, the equilibrium equation is established. The influences of applied voltage, dimensionless geometrical parameter and piezoelectric thickness on the critical buckling load of beam are presented. To investigate the accuracy of the present analysis, a compression study is carried out with a known data.Keywords: Mechanical Buckling, Engesser-Timoshenko beam theory - Piezoelectric layer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22401396 Off-Line Signature Recognition Based On Angle Features and GRNN Neural Networks
Authors: Laila Y. Fannas, Ahmed Y. Ben Sasi
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This research presents a handwritten signature recognition based on angle feature vector using Artificial Neural Network (ANN). Each signature image will be represented by an Angle vector. The feature vector will constitute the input to the ANN. The collection of signature images will be divided into two sets. One set will be used for training the ANN in a supervised fashion. The other set which is never seen by the ANN will be used for testing. After training, the ANN will be tested for recognition of the signature. When the signature is classified correctly, it is considered correct recognition otherwise it is a failure.
Keywords: Signature Recognition, Artificial Neural Network, Angle Features.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2495