Engineering Commons^™

Egoviz – A Mobile Based Spatial Interaction System, Keith Gardiner, Junjun Yin, James Carswell

Articles

This paper describes research carried out in the area of mobile spatial interaction and the development of a mobile (i.e. on-device) version of a simulated web-based 2D directional query processor. The TellMe application integrates location (from GPS, GSM, WiFi) and orientation (from digital compass/tilt sensors) sensing technologies into an enhanced spatial query processing module capable of exploiting a mobile device’s position and orientation for querying real-world 3D spatial datasets. This paper outlines the technique used to combine these technologies and the architecture needed to deploy them on a sensor enabled smartphone (i.e. Nokia 6210 Navigator). With all these sensor technologies …

Microwave-Assisted Synthesis Of Zno Micro-Javelins, Suresh Pillai, Declan Mccormack, John M. Kelly, Sibu C. Padmanabhan

Articles

The microwave (MW)-assisted formation of ZnO micro-javelins from zinc nitrate and urea in aqueous solution is described. The particles (named as ‘micro-javelins’ because of their high aspect ratio and needle-like tips) grow hexagonally with well-defined facets in the h0110i direction and pointed tips in (0001) direction. Powder X-ray diffraction patterns show the appearance of a strikingly dominant (1000) orientation. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations reveal the morphological evolution of these hexagonal ZnO particles with time. The effect of precursor concentrations, counterion type andMWirradiation power and their consequent influence on pH and Zn2+ ion concentration are …

Influence Of Solar Heating On The Performance Of Integrated Solar Cell Microstrip Patch Antennas, Maria Roo Ons, S. Shynu, M Seredynski, Max Ammann, Sarah Mccormack, Brian Norton

Articles

The integration of microstrip patch antennas with photovoltaics has been proposed for applications in autonomous wireless communication systems located on building façades. Full integration was achieved using polycrystalline silicon solar cells as both antenna ground plane and direct current power generation in the same device. An overview of the proposed photovoltaic antenna designs is provided and the variation characterised of the electromagnetic properties of the device with temperature and solar radiation. Measurements for both copper and solar antennas are reported on three different commercial laminates with contrasting values for thermal coefficient of the dielectric constant.

Directional Dual-Band Slot Antenna With Dual-Bandgap High-Impedance-Surface Reflector, Xiulong Bao, Giuseppe Ruvio, Max Ammann

Articles

A compact dual-band high-impedance-surface EBG structure is employed as a reflector for a dual-band annular-slot antenna. The reflector comprises an array of miniaturized EBG cells which utilizes square patches augmented by four S-shaped corrugated arms to reduce the resonant frequency of the proposed EBG structure. In order to broaden the bandwidth and adjust the frequency ratio for the dual-band EBG structure, a log-periodic spacing between the S-shaped strips is introduced. The combination of microstrip-fed annular slot and EBG reflector provides directional properties for both frequency bands with reduced size and low-profile.

Radial Ebg Cell Layout For Gps Patch Antennas, Giuseppe Ruvio, Max Ammann, Xiulong Bao

Articles

A novel radial layout for mushroom-like electromagnetic-bandgap (EBG) cells surrounding a printed circularly-polarised patch antenna is proposed. Two radial EBG configurations surrounding a circular patch are compared to a reference patch on a conventional ground plane of the same dimension. The radial shape and displacement of the EBG cells around the patch offers improvements in terms of gain and axial-ratio compared to the reference antenna and is more suitable for circular geometries compared to conventional Cartesian layouts. In particular, the distance between the patch and the surrounding EBG cells is independent of the cell period, which can be arbitrarily chosen, …

Temperature Induced Instabilities In Macro-Bend Fiber Based Wavelength Measurement Systems, Ginu Rajan, Yuliya Semenova, Pengfei Wang, Gerald Farrell

Articles

An investigation of temperature-induced instabilities in a wavelength measurement system based on macro-bend fiber filter used in the ratiometric scheme are presented. Two wavelength measurement systems based on macro-bend fiber, a standard low bend loss single-mode fiber filter based system and a high bend loss fiber filter based system are considered. In the case of a low bend loss fiber filter based system, the oscillatory variation in the ratio response with temperature and the difference in the temperature-induced ratio variation at different wavelengths makes the temperature corrected calibration of the system unfeasible, which is essential for precise wavelength measurements. The …

Reflection Contributions To The Dispersion Artefact In Ftir Spectra Of Single Biological Cells, Paul Bassan, Hugh Byrne, Joe Lee, Franck Bonnier, Colin Clarke, Paul Dumas, Ehsan Gazi, Michael Brown, Noel Clarke, Peter Gardner

Articles

Fourier transform infrared spectra of a single cell in transflection geometry are seen to vary significantly with position on the cell, showing a distorted derivative-like lineshape in the region of the optically dense nucleus. A similar behaviour is observable in a model system of the protein albumin doped in a potassium bromide disk. It is demonstrated that the spectrum at any point is a weighted sum of the sample reflection and transmission and that the dominance of the reflection spectrum in optically dense regions can account for some of the spectral distortions previously attributed to dispersion artefacts. Rather than being …

Investigation Of Polarization Dependent Loss For A Macrobending Loss, Pengfei Wang, Gerald Farrell, Yuliya Semenova, Ginu Rajan

Articles

An investigation of the polarization dependent loss (PDL) of macrobending
loss sensitive single fiber (1060XP) is presented theoretically and experimentally. The
experimental results are in good agreement with the modeling outcomes. Through the
comparison of experimental results of PDL between 1060XP fiber with coatings and
bare 1060XP fiber, it is shown that the fiber coating has significant impact on the PDL
of bend loss sensitive singlemode fiber

One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat

Articles

No abstract provided.

Sms Fibre Structure For Temperature Measurement Using A Simple Intensity-Based Interrogation System, Agus Hatta, Ginu Rajan, Yuliya Semenova, Gerald Farrell

Articles

A singlemode–multimode–singlemode (SMS) fibre structure for temperature measurement that utilises a simple intensity-based interrogation system is proposed. The temperature dependence of the SMS fibre structure utilised as a sensor is investigated numerically and experimentally. It is found that a strong temperature dependence for the SMS fibre structure exists at selected wavelengths. The temperature characteristic at such wavelengths is linear in nature and can be used for temperature measurements. The proposed temperature sensor offers a high resolution and accuracy, and also benefits from a simple configuration and low cost when compared to other fibre-optic temperature sensors.

A Covert Encryption Method For Applications In Electronic Data Interchange, Jonathan Blackledge, Dmitry Dubovitskiy

Articles

A principal weakness of all encryption systems is that the output data can be ‘seen’ to be encrypted. In other words, encrypted data provides a ‘flag’ on the potential value of the information that has been encrypted. In this paper, we provide a new approach to ‘hiding’ encrypted data in a digital image.

In conventional (symmetric) encryption, the plaintext is usually represented as a binary stream and encrypted using an XOR type operation with a binary cipher. The algorithm used is ideally designed to: (i) generate a maximum entropy cipher so that there is no bias with regard to any …

The Effect Of Air Preheating In A Biomass Cfb Gasifier Using Aspen Plus Simulation, Wayne Doherty, Anthony Reynolds, David Kennedy

Articles

In the context of climate change, increasing efficiency and energy security, biomass gasification is likely to play an important role in energy production. Atmospheric circulating fluidised bed (CFB) technology was selected for the current study. The primary objective of this research is to develop a computer simulation model of a CFB biomass gasifier that can accurately predict gasifier performance under various operating conditions. An original model was developed using ASPEN Plus (Advanced System for Process ENgineering Plus). The model is based on Gibbs free energy minimisation. The restricted equilibrium method was used to calibrate the model against experimental data. This …

Providing Academic Leadership Through The Role Of Senior Lecturer 1 (Teaching) Using The Theme Of 'Sustainable Energy' As An Example, Jim Mcgovern

Articles

An academic leader should lead in their particular area and should love what they are doing. An example of leadership in the area of 'sustainable energy use' is presented that involves leading through identifying and participating in the development of emerging technologies. Excellent academic leadership can be provided by a Senior Lecturer through active research, incorporating the latest developments in student-centred learning in their work and providing example and encouragement for colleagues and learners.

Emitter-Wrap-Through Photovoltaic Dipole Antenna With Solar Concentrator, Maria Roo Ons, S. Shynu, Max Ammann, Sarah Mccormack, Brian Norton

Articles

A novel photovoltaic dipole antenna employing a solar concentrator as a reflector is proposed. Four identical emitter-wrap-through rear contact solar cells connected in series as a folded dipole are simultaneously used for power generation and as the antenna radiating element, which is located in the focal line of a parabolic solar concentrator. The parabolic structure acts as a solar concentrator for the photovoltaic cells as well as a reflector for the folded dipole antenna. Full-wave electromagnetic simulation with supportive experimental work validates this design. The measured fractional impedance bandwidth and gain were 21% and 11.1 dBi, respectively. The antenna/solar arrangement …

Titanium Dioxide Nanoparticles Induce Oxidative Stress And Dna-Adduct Formation But Not Dna-Breakage In Human Lung Cells, Kunal Bhattacharya, Maria Davoren, Jens Boertz, Roel P.F. Schins, Eik Hoffmann, Elke Dopp

Articles

Titanium dioxide (TiO2), also known as titanium (IV) oxide or anatase, is the naturally occurring oxide of titanium. It is also one of the most commercially used form. To date, no parameter has been set for the average ambient air concentration of TiO2 nanoparticles (NP) by any regulatory agency. Previously conducted studies had established these nanoparticles to be mainly non-cyto- and -genotoxic, although they had been found to generate free radicals both acellularly (specially through photocatalytic activity) and intracellularly. The present study determines the role of TiO2-NP (anatase, ∅ < 100 nm) using several parameters such as cyto- and genotoxicity, DNA-adduct formation and generation of free radicals following its uptake by human lung cells in vitro. For comparison, iron containing nanoparticles (hematite, Fe2O3, ∅ < 100 nm) were used. The results of this study showed that both types of NP were located in the cytosol near the nucleus. No particles were found inside the nucleus, in mitochondria or ribosomes. Human lung fibroblasts (IMR-90) were more sensitive regarding cyto- and genotoxic effects caused by the NP than human bronchial epithelial cells (BEAS-2B). In contrast to hematite NP, TiO2-NP did not induce DNA-breakage measured by the Comet-assay in both cell types. Generation of reactive oxygen species (ROS) was measured acellularly (without any photocatalytic activity) as well as intracellularly for both types of particles, however, the iron-containing NP needed special reducing conditions before pronounced radical generation. A high level of DNA adduct formation (8-OHdG) was observed in IMR-90 cells exposed to TiO2-NP, but not in cells exposed to hematite NP. Our study demonstrates different modes of action for TiO2- and Fe2O3-NP. Whereas TiO2-NP were able to generate elevated amounts of free radicals, which induced indirect genotoxicity mainly by DNA-adduct formation, Fe2O3-NP were clastogenic (induction of DNA-breakage) and required reducing conditions for radical formation.

The Bundle Dispersion Of Swnt On Interaction With P-Terphenyl, Theresa Hedderman, Anika Mostaert, Anne Shanahan, Hugh Byrne

Articles

This paper investigates the interaction and bundle dispersion of single walled carbon nanotubes (SWNT) produced by arc discharge and by the high pressure decomposition of carbon monoxide, often referred to as the HiPco method, in the presence of the molecule p-terphenyl. The study will show that the extent of SWNT bundle dispersion and the degree of interaction with p-terphenyl is related to the level of purity of the SWNT sample. This study compares the bundle dispersion and interaction of SWNT with p-terphenyl in their as produced state and after purification. A number of spectroscopic and microscopic techniques are used to …

Synthesis Of Maleic Anhydride Grafted Polypropylene-Butadiene Copolymer And Its Application In Pp/Ommt/Sbs Composite As Compatibilizer, Qiaohuan Cheng, Zhanxia Lu, Hugh Byrne

Articles

Maleic Anhydride (MA) grafted propylene-butadiene copolymer (PPB) was prepared. FTIR and 1H-NMR results indicated that the MA molecules reacted with the double bond in the butadiene unit of the PPB and the grafting percentage increased with the butadiene content in the initial copolymer. GPC results showed the introduction of butadiene in the copolymer prevented the degradation of the PPB. The MA-g-PPB (MPPB) was applied in PP/SBS/OMMT composite as compatibilizer. In the presence of 10phr MPPB, the impact strength of the composite was improved by ~20%. XRD patterns indicated the formation of β-phase crystallization of polypropylene in the presence of MPPB …

Preparation, Characterization Of Nipam And Nipam/Bam Copolymer Nanoparticles And Their Acute Toxicity Testing Using An Aquatic Test Battery, Pratap Naha, Alan Casey, Tiziana Tenuta, Iseult Lynch, Kenneth Dawson, Hugh Byrne, Maria Davoren

Articles

Poly N-isopropylacrylamide and N-isopropylacrylamide / N-tert-butylacrylamide copolymer nanoparticles of 50 to 70 nm were prepared by free radical polymerisation. The particle sizes of the copolymer nanoparticles were measured in the test media MilliQ water, Algae Media, Daphnia Media and Microtox Diluent as a function of temperature. Whereas in MilliQ water the particle size was seen to decrease above the lower critical solution temperature of the thermoresponsive polymer, in the test media it was seen to increase significantly, indicative of aggregation. At the temperatures employed for the ecotoxicological studies all particles, with the exception of the 50:50copolymer existed as nanoparticles, however. …

Engineering Of A Single Alkaline Fuel Cell Part I: Construction Of A Test Bed, Jonathan Blackledge, James Brunton, Eugene Coyle, David Kennedy, Heinz Schmidt-Walter, Hans Kohnke, Gerhard Sauer, Steffen Schudt, James Hamilton

Articles

Fuel Cells offer a realistic, sustainable and clean alternative energy option for stationary and mobile applications. Hydrogen and fuel cell technologies are recognised by many as possible long term energy solutions, but to-date have failed to make an impact on the energy market. This is due to a number of key reasons, some of which include, efficiency, scale, accessories and power output. Applying fuel cells to small telecommunication components requires the applications of Micro and Nanotechnology, which have yet to be perfected to make them long lasting and cost effective. This paper outlines the reasons for commercialisation of fuel cells …

Engineering Of A Single Alkaline Fuel Cell Part Ii: Long Term Operation In Air, Jonathan Blackledge, Eugene Coyle, David Kennedy, Heinz Schmidt-Walter, Hans Kohnke, Steffen Schudt, Gerhard Sauer, James Hamilton

Articles

Research into renewable energy sources has previously lacked sufficient investment. However, emphasis has now shifted and funding is being made available in a proactive manner by various governments eager to encourage renewable energy technology and reduce carbon taxes. Fuel Cells offer a realistic, sustainable and clean alternative energy option for stationary and mobile applications. Hydrogen and fuel cell technologies are recognised by many as possible long term energy solutions, but to-date, have failed to make an impact on the energy market. This is due to a number of key reasons, some of which include efficiency, scale, accessories and power output. …

Inverse Scattering Solutions With Applications To Electromagnetic Signal Processing, Jonathan Blackledge, Timo Hamalainen, Jyrki Joutsensalo

Articles

When a signal is recorded that has been physically generated by some scattering process (the interaction of electromagnetic, acoustic or elastic waves with inhomogeneous materials, for example), the ‘standard model’ for the signal (i.e. information content convolved with a characteristic Impulse Response Function) is usually based on a single scattering approximation. An additive noise term is introduced into the model to take into account a range of non-deterministic factors including multiple scattering that, along with electronic noise and other background noise sources, is assumed to be relatively weak. Thus, the standard model is based on a ‘weak field condition’ and …

Integration Of Microstrip Patch Antennas With Polycrystalline Silicon Solar Cells, S. Shynu, Maria Roo Ons, Max Ammann, Sarah Mccormack, Brian Norton

Articles

The implementation of a polycrystalline silicon solar cell as a microwave groundplane in a low-profile, reduced-footprint microstrip patch antenna design for autonomous communication applications is reported. The effects on the antenna/solar performances due to the integration, different electrical conductivities in the silicon layer and variation in incident light intensity are investigated. The antenna sensitivity to the orientation of the anisotropic solar cell geometry is discussed.

Simple Versatile Shearing Interferometer Suitable For Measurements On A Microscopic Scale, Emilia Mihaylova, Vincent Toal

Articles

Microelectromechanical systems (MEMS) behave differently from massive samples. Conventional testing and inspection techniques usually fail at the microscale. Recently there has been an increasing interest in the application of optical techniques for microstructure testing, because they are high-resolution, non-contact, full-field, fast and relatively inexpensive. New interferometric systems, which are suitable for microscopic optical metrology, are of interest for engineering and industrial applications. A modified electronic speckle pattern shearing interferometer (ESPSI) with a very simple shearing device has been designed for metrology applications on the microscale. The shearing device consists of two partially reflective glass plates. The reflection coefficients of the …

Emitter-Wrap-Through Photovoltaic Dipole Antenna With Solar Concentrator, Maria Roo Ons, S. Shynu, Max Ammann, Sarah Mccormack, Brian Norton

Articles

A novel photovoltaic dipole antenna employing a solar concentrator as a reflector is proposed. Four identical emitter-wrap-through rear contact solar cells connected in series as a folded dipole are simultaneously used for power generation and as the antenna radiating element, which is located in the focal line of a parabolic solar concentrator. The parabolic structure acts as a solar concentrator for the photovoltaic cells as well as a reflector for the folded dipole antenna. Full-wave electromagnetic simulation with supportive experimental work validates this design. The measured fractional impedance bandwidth and gain were 21% and 11.1 dBi, respectively. The antenna/solar arrangement …

Generalised Design Process For Fiber-Bend-Loss-Based Edge Filters For A Wavelength Measurement System, Pengfei Wang, Gerald Farrell, Yuliya Semenova

Articles

We investigate and present a generalized methodology for the design of a fiber-bend-loss-based edge filter, starting with the task of evaluating and selecting suitable fibers and then considering the design of a fiber-bending-loss edge filter. As an example to illustrate the methodology, a Corning SMF28e fiber with a 900 μmdiameter is selected and two sample edge filters are designed for experimental verification. The designed edge filters are compact, easy to fabricate, meet target spectral specifications, and show low polarization-dependent loss, confirming the effectiveness of the proposed methodology for fiber-bend-loss-based edge filter design.

Misalignment Limits For A Singlemode-Multimode-Singlemode Fiber-Based Edge Filter, Agus Hatta, Gerald Farrell, Pengfei Wang, Ginu Rajan, Yuliya Semenova

Articles

Misalignment effects on the spectral characteristics of edge filters based on singlemode–multimode–singlemode (SMS) fibre structures are investigated numerically and experimentally. A modal propagation analysis is used with a set of guided modes calculated using the finite-difference method to determine the transmission loss of the SMS-based edge filters. A limit for the tolerable misalignment of the SMS fiber-based edge filter is proposed, beyond which the spectral performance of the SMS structure degrades unacceptably. The numerical results are verified experimentally with good agreement.

A Macrobending Singlemode Fiber Based Refractometer, Pengfei Wang, Yuliya Semenova, Qiang Wu, Gerald Farrell, Yungqiang Ti, Jie Zheng

Articles

A novel macrobending based all-fiber refractometer sensor with a simple optical configuration is proposed and investigated both theoretically and experimentally. The proposed fiber refractometer sensor consists of a single loop structure of bare macrobending standard singlemode fiber (SMF28) with a selected bending radius and reduced cladding diameter. The well-known scalar approximation theory is employed to theoretically predict the characteristics of the proposed fiber refractometer sensor. An approach to improve the resolution of the refractometer is presented, which shows that the refractometer with a reduced cladding diameter of 81 μm has an experimentally verified resolution of 5.75105 for a refractive index …

Analysis And Performance Evaluation Of An All-Fiber Wide Range Interrogation System For A Bragg Grating Sensor Array, Ginu Rajan, Yuliya Semenova, Gerald Farrell

Articles

Analysis and performance evaluation of a macro-bend ¯ber based interrogation system for a Bragg grating sensor array is presented. Due to the characteristic properties of the macro-bend ¯ber ¯lter such as polarization and temperature dependence and the total noise associated with the ratiometric system, a best ¯t ratio slope is required to interrogate multiple FBGs whose peak wavelengths are spread over a wide wavelength range, rather than the optimal slope for individual FBG. In this paper for investigation we have used an FBG array with 5 FBGs with peak re°ected wavelengths lying between 1525 nm and 1575 nm. The analysis …

High Resolution Temperature Insensitive Interrogation Technique For Fbg Sensors, Qiang Wu, Yuliya Semenova, An Sun, Pengfei Wang, 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 better …

Use Of A Single-Multiple-Single-Mode Fiber Filter For Interrogating Fiber Bragg Grating Strain Sensors With Dynamic Temperature Compensation, Qiang Wu, Muhammad Hatta, Yuliya Semenova, Gerald Farrell

Articles

An interrogation technique for fiber Bragg grating (FBG) strain sensors with dynamic temperature compensation using a single-multiple-single-mode (SMS) fiber filter as a temperature compensating element is presented. Experimental results show that this technique offers a resolution of better than 3:4 με for strain measurements in the range from 0 to 1667 με, and the temperature induced error is as low as 34 με in the temperature range from 10 to 60 °C. The temperature induced error could be further reduced if the temperature sensitivity (the rate of temperature induced wavelength shift) of the SMS filter was closer to that of …