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Passive All-Fiber Wavelength Measurement Systems: Performance Determination Factors, Ginu Rajan, Yuliya Semenova, Agus Hatta, Gerald Farrell 2010 Dublin Institute of Technology

Passive All-Fiber Wavelength Measurement Systems: Performance Determination Factors, Ginu Rajan, Yuliya Semenova, Agus Hatta, Gerald Farrell

Books/Book Chapters

No abstract provided.


Simulation Procedure For The Co-Optimization Of Photovoltaic Water Pumping Systems., Brian Norton 2010 Dublin Institute of Technology

Simulation Procedure For The Co-Optimization Of Photovoltaic Water Pumping Systems., Brian Norton

Articles

Abstract: Photovoltaic (PV)-powered centrifugal water pumping systems have been modelled based on field experience and analysis of long-term measured performance of several installed PV-powered water pumping systems. This paper presents detailed modelling of a PV array, an inverter, a three-phase induction motor, a centrifugal pump, a well, a storage tank, an overflow controller, and an integrated reverse osmosis desalination unit. The component models were validated using both laboratory measurements and long-term monitored data. All system components have been modelled separately, and the system was modelled in TRNSYS. The models are capable of simulating grid-connected, diesel-powered, and PV-powered water pumping ...


Strain Sensor Based On A Pair Of Single-Mode-Multimode-Single-Mode Fiber Structures In A Ratiometric Power Measurement Scheme, Agus Hatta, Yuliya Semenova, Qiang Wu, Gerald Farrell 2010 Dublin Institute of Technology

Strain Sensor Based On A Pair Of Single-Mode-Multimode-Single-Mode Fiber Structures In A Ratiometric Power Measurement Scheme, Agus Hatta, Yuliya Semenova, Qiang Wu, Gerald Farrell

Articles

The strain and temperature dependencies of a step-index single-mode–multimode–single-mode (SMS) fiber structure are investigated numerically and experimentally. For intensity-based strain measurement using a single SMS fiber structure, at a selected wavelength, it is found that there is a high strain dependence, but also a temperature dependence that will induce strain measurement error. To minimize the temperature-induced strain measurement error, two SMS fiber structures are proposed and demonstrated in a ratiometric power measurement scheme; one SMS structure acts as the strain sensor, and the other SMS structure acts as the temperature monitor. The extracted temperature information is used to ...


A Voltage Sensor Based On A Singlemode-Multimode-Singlemode Fiber Structure, Agus Hatta, Yuliya Semenova, Ginu Rajan, Gerald Farrell 2010 Dublin Institute of Technology

A Voltage Sensor Based On A Singlemode-Multimode-Singlemode Fiber Structure, Agus Hatta, Yuliya Semenova, Ginu Rajan, Gerald Farrell

Articles

A voltage sensor based on a singlemode-multimodesinglemode (SMS) fiber structure, attached to a piezoelectric (PZT), utilized in a ratiometric optical power measurement scheme is proposed. The elongation of the PZT due to an applied voltage induces a strain on the SMS fiber structure and in turn results in a change in the transmission loss response of the SMS fiber structure. It is found that at selected wavelengths, a strong voltage dependence for the transmission loss of the SMS fiber structure can be achieved. The voltage information can be obtained from the power ratio of the system, assuming the system is ...


Optimum Design For Maximun Wavelength Resolution For An Edge Filter Based Ratiometric System, Qiang Wu, Ginu Rajan, Pengfei Wang, Yuliya Semenova, Gerald Farrell 2010 Dublin Institute of Technology

Optimum Design For Maximun Wavelength Resolution For An Edge Filter Based Ratiometric System, Qiang Wu, Ginu Rajan, Pengfei Wang, Yuliya Semenova, Gerald Farrell

Articles

In this letter, we propose a high resolution temperature insensitive interrogation technique for FBG sensors where one FBG acts as an edge filter to interrogate a separate FBG sensor. A high resolution of better than 5 με in strain measurement range from 0 to 1100 με and the best resolution of better than 1 με were verified by experiments. An error of only ±2.2 με is achieved over a temperature range from 15 to 50 °C, indicating that this strain interrogation technique is temperature insensitive. Using an altered system configuration, the temperature was also measured simultaneously with a resolution ...


A Macrobending Singlemode Fiber Refractive Index Sensor For Low Refractive Index Liquids, Pengfei Wang, Yuliya Semenova, Yong Li, Qiang Wu, Gerald Farrell 2010 Dublin Institute of Technology

A Macrobending Singlemode Fiber Refractive Index Sensor For Low Refractive Index Liquids, Pengfei Wang, Yuliya Semenova, Yong Li, Qiang Wu, Gerald Farrell

Articles

An all-fiber refractive index sensor with a simple configuration is proposed and investigated. The proposed fiber refractometer consists of a full-loop structure of bare high-bend loss singlemode fiber-1060XP, employing the well-known whispering gallery mode (WGM) effect induced by the evanescent wave excitation to measure the refractive index of an external medium. A competitive sensitivity is achieved (average 725.76nm/RIU at a bend diameter of 19.3mm) compared with other fiber-optic sensors, plus benefits resulting from simplicity, low cost and ease of fabrication.


Humidity Sensor Based On A Photonic Crystal Fiber Interferometer, Jinesh Mathew, Yuliya Semenova, Ginu Rajan, Gerald Farrell 2010 Dublin Institute of Technology

Humidity Sensor Based On A Photonic Crystal Fiber Interferometer, Jinesh Mathew, Yuliya Semenova, Ginu Rajan, Gerald Farrell

Articles

A photonic crystal fiber interferometer that operates in reflection mode for humidity detection is presented for the first time which has the advantage that it does not require the use of any hygroscopic material. The fabrication of the sensor head is therefore simple since it only involves cleaving and splicing. The all-silica nature of the device has the potential for many applications.


A Study Of The Effect Of The Position Of An Edge Filter Within A Ratiometric Wavelength Measurement System, Qiang Wu, Pengfei Wang, Yuliya Semenova, Gerald Farrell 2010 Dublin Institute of Technology

A Study Of The Effect Of The Position Of An Edge Filter Within A Ratiometric Wavelength Measurement System, Qiang Wu, Pengfei Wang, Yuliya Semenova, Gerald Farrell

Articles

The effect of the position of an edge filter within a ratiometric wavelength measurement system was investigated based on three cases: (1) the reflected fibre Bragg grating (FBG) signal passes through both the reference arm and the edge filter arm, (2) the reflected FBG signal is connected directly to the edge filter arm and does not pass through the reference arm, (3) the edge filter sits in line with the FBG and thus the source power is filtered prior to reaching the FBG. Both numerical simulations and experimental results show that cases 1 and 2 have similar system performance whilst ...


Interactive Music Archive Access System, Martin Gallagher, Derry Fitzgerald, Dan Barry, Matt Cranitch, Eugene Coyle 2010 Dublin Institute of Technology

Interactive Music Archive Access System, Martin Gallagher, Derry Fitzgerald, Dan Barry, Matt Cranitch, Eugene Coyle

Conference papers

The goal of the Interactive Music Archive Access System (IMAAS) project was to develop an interactive music archive access system which was capable of allowing an end-user to easily extract rhythmic, melodic and harmonic musical metadata descriptors from audio, and allow the user to interact with the archive contents in a manner not typically allowed in archive access systems. To this end, the IMAAS system incorporates a range of real-time interaction tools which allow the user to modify the retrieved audio in a number of ways including the ability to isolate individual instruments in stereo mixes, pitch and time-scale modification ...


Simple Design Technique For A Triangular Fbg Filter Based On A Linearly Chirped Grating, Qiang Wu, Gerald Farrell, Yuliya Semenova 2010 Dublin Institute of Technology

Simple Design Technique For A Triangular Fbg Filter Based On A Linearly Chirped Grating, Qiang Wu, Gerald Farrell, Yuliya Semenova

Articles

A novel and simple design technique for triangular spectrum response of fibre Bragg grating (FBG) is pre- 21 sented based on a linear chirped grating. It is shown that this method is fast and can give a straightfor- 22 ward solution to meet a design target. The numerical simulation examples verified the effectiveness of 23 the design method. A general approach to design for multichannel triangular spectral responses for 24 FBG filters is proposed, which provides a solution that achieves a minimum change of refractive index 25 for the fibre.


Adaptation Of Pyflag To Efficient Analysis Of Seized Computer Data Storage, Aleksander Byrski, Wojciech Stryjewski, Bartłomiej Czechowicz 2010 AGH University of Science and Technology

Adaptation Of Pyflag To Efficient Analysis Of Seized Computer Data Storage, Aleksander Byrski, Wojciech Stryjewski, Bartłomiej Czechowicz

Journal of Digital Forensics, Security and Law

Based on existing software aimed at investigation support in the analysis of computer data storage seized during investigation (PyFlag), an extension is proposed involving the introduction of dedicated components for data identification and filtering. Hash codes for popular software contained in NIST/NSRL database are considered in order to avoid unwanted files while searching and to classify them into several categories. The extension allows for further analysis, e.g. using artificial intelligence methods. The considerations are illustrated by the overview of the system's design.


Table Of Contents, 2010 Embry-Riddle Aeronautical University

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.


Optical Control Of Ultrafast Spin -Wave Relaxation By Magnetic Anisotropy In A Ferromagnet, Kevin James Smith 2010 College of William & Mary - Arts & Sciences

Optical Control Of Ultrafast Spin -Wave Relaxation By Magnetic Anisotropy In A Ferromagnet, Kevin James Smith

Dissertations, Theses, and Masters Projects

This thesis presents an investigation of the damping of spin waves in ferromagnetic Au(3 nm)/Ni(10 nm)/MgO(001) thin films using the time-resolved Magneto-optical Kerr Effect (TR-MOKE) and ferromagnetic resonance (FMR) techniques. In the optical measurements, a 150 fs, 800 nm laser beam pulse is split into pump and probe components. The pump pulse, containing most of the beam energy, thermally excites coherent spin precession. The weaker probe pulse, time-delayed by a variable beam path, captures the magnetization dynamics via the polar MOKE effect, and oscillations are observed as a function of external field amplitude and direction ...


Denoising Of Natural Images Using The Wavelet Transform, Manish Kumar Singh 2010 San Jose State University

Denoising Of Natural Images Using The Wavelet Transform, Manish Kumar Singh

Master's Theses

A new denoising algorithm based on the Haar wavelet transform is proposed. The methodology is based on an algorithm initially developed for image compression using the Tetrolet transform. The Tetrolet transform is an adaptive Haar wavelet transform whose support is tetrominoes, that is, shapes made by connecting four equal sized squares. The proposed algorithm improves denoising performance measured in peak signal-to-noise ratio (PSNR) by 1-2.5 dB over the Haar wavelet transform for images corrupted by additive white Gaussian noise (AWGN) assuming universal hard thresholding. The algorithm is local and works independently on each 4x4 block of the image. It ...


Crack Detectability And Durability Of Coaxial Cable Sensors In Reinforced Concrete Bridge Applications, Genda Chen, Ryan D. McDaniel, Michael A. Brower, David Pommerenke 2010 Missouri University of Science and Technology

Crack Detectability And Durability Of Coaxial Cable Sensors In Reinforced Concrete Bridge Applications, Genda Chen, Ryan D. Mcdaniel, Michael A. Brower, David Pommerenke

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The working mechanism and the measurement principle of topology-based crack sensors made of coaxial cables are briefly reviewed. The sensitivity, spatial resolution, and ruggedness of two coaxial cable sensors, respectively made of rubber and Teflon dielectric materials, were compared and validated with laboratory testing of a 4/5-scale, T-shaped, reinforced concrete beam-column specimen. Two Teflon sensors were installed on one of the solid decks of a three-span continuous highway bridge to investigate their durability and measurement repeatability. Laboratory tests indicated that both types of sensors have high sensitivity, but the Teflon sensor has a higher spatial resolution and a negligible ...


Dynamics And Control Of An Electric Power Assist Steering System, Prasanth Babu Kandula 2010 Cleveland State University

Dynamics And Control Of An Electric Power Assist Steering System, Prasanth Babu Kandula

ETD Archive

In this thesis an Active Disturbance Rejection Controller (ADRC) is applied to Electrical Power Assist Steering (EPAS) system which assists the driver in steering the steering wheel of an automobile. Our control objective is to reduce the steering torque exerted by a driver, so that good steering feel of the driver will be achieved in the presence of external disturbances and system uncertainties which are very common in the EPAS system. The robustness and stability of ADRC controlled EPAS system is investigated through frequency-domain analyses. The Bode diagrams and stability margins demonstrate that the control system is stable during the ...


Fadaptive Backstepping Control Of Active Magnetic Bearings, Silu You 2010 Cleveland State University

Fadaptive Backstepping Control Of Active Magnetic Bearings, Silu You

ETD Archive

A new control methodology, adaptive backstepping control (ABC), is applied to a linearized model of an active magnetic bearing (AMB). Our control objective is to regulate the deviation of the magnetic bearing from its equilibrium position in the presence of an external disturbance. The control approach is based on adaptive backstepping control, which is a combination of a recursive Lyapunov controller and adaptive laws. In this thesis, two types of adaptive backstepping methods are used. The first method is based on full-state feedback, for which all three states in the linearized AMB model (velocity, position, and current) are used to ...


Sensing And Control Of Mems Accelerometers Using Kalman Filter, Kai Zhang 2010 Cleveland State University

Sensing And Control Of Mems Accelerometers Using Kalman Filter, Kai Zhang

ETD Archive

Surface micromachined low-capacitance MEMS capacitive accelerometers which integrated CMOS readout circuit generally have a noise above 0.02g. Force-to-rebalance feedback control that is commonly used in MEMS accelerometers can improve the performances of accelerometers such as increasing their stability, bandwidth and dynamic range. However, the controller also increases the noise floor. There are two major sources of the noise in MEMS accelerometer. They are electronic noise from the CMOS readout circuit and thermal-mechanical Brownian noise caused by damping. Kalman filter is an effective solution to the problem of reducing the effects of the noises through estimating and canceling the states ...


A Generalized Inverter Control Method For A Variable Speed Wind Power System Under Unbalanced Operating Conditions, Shuang Wu 2010 Cleveland State University

A Generalized Inverter Control Method For A Variable Speed Wind Power System Under Unbalanced Operating Conditions, Shuang Wu

ETD Archive

This thesis presents a generalized control method for complete harmonic elimination and adjustable power factor of a grid side inverter under unbalanced operating conditions used in variable speed wind power systems. The theoretical analysis of the proposed control method is described and verified by simulation in Simulink®. Two types of traditional control methods are also explained and applied in the wind power system for comparison, which are the indirect current control in a-b-c reference frame and the active and reactive power control in d-q synchronous frame. This method is verified for the gird fault right-through operation as well


Dc-Dc Power Converter Design For Application In Welding Power Source For The Retail Market, Edward J. Oshaben 2010 Cleveland State University

Dc-Dc Power Converter Design For Application In Welding Power Source For The Retail Market, Edward J. Oshaben

ETD Archive

The purpose of this study is to design and analyze a DC-DC power converter for application in a welding power source that is cost-competitive with the more traditional, lower-tech welding power source topologies. This thesis first presents a background study of recent design approaches to DC-DC power converters, as they relate to application in welding power converters. The background study also surveys recent design approaches to welding power source controls. Evaluation of available options in DC-DC converter topologies and switching schemes for application in a welding power source is presented. Design methodology of a low-cost DC-DC converter for application in ...


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