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- Keyword
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- Mach-Zehnder interferometer (2)
- Phase change material (2)
- Refractive index (2)
- Temperature (2)
- Acoustic emission sensors (1)
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- Air (1)
- All-fiber comb filter (1)
- Antenna (1)
- Associations (1)
- Balloon-shaped bent multimode (1)
- Band-pass filters (1)
- Beam propagation method (1)
- Bent-core liquid crystals (1)
- Biaxiality (1)
- Brand (1)
- Burst pulses (1)
- Clusters (1)
- Cognitive mapping (1)
- Compound glass; microsphere; resonator; lasing; sensing (1)
- Corona (1)
- CuringOptical fibersResonatorsTemperature distributionTemperature sensorsThermal expansion (1)
- Data Visualization (1)
- Dendrite tip kinetics model (1)
- Dendritic crystal structures (1)
- Dielectric spectroscopy (1)
- Dipole antennas (1)
- Displacement measurement (1)
- Dynamic voltage restorer (1)
- Electronic methods (electrochemical) chlorine ions (1)
- FBG (1)
Articles 1 - 29 of 29
Full-Text Articles in Engineering
Improving Operator Situation Awareness By Phasor Measurement Unit (Pmu) Data Visualization, Esa M. Rantanen, Ernest Fokoue, Jacob Haut, Chandini Ramesh, Kathleen Gegner, Thomas Overbye, Komal Shetye
Improving Operator Situation Awareness By Phasor Measurement Unit (Pmu) Data Visualization, Esa M. Rantanen, Ernest Fokoue, Jacob Haut, Chandini Ramesh, Kathleen Gegner, Thomas Overbye, Komal Shetye
Articles
The application of phasor measurement unit (PMU) data in the power industry is currently an area of intense interest. The key driver for PMU technology is to use the precise time sources provided by Global Positioning System (GPS) satellites to accurately measure the relative voltage and current phase angles at buses across an interconnect at a very high sampling rate. Presenting PMU data to power system operators in a format that is truly useful for them and that affords improved situation awareness (SA) and fast and accurate decision making is a particular challenge to display design. This report describes development …
Using Cognitive Mapping To Longitudinally Examine Political Brand Associations, Ewan Alexander Macdonald, Roger Sherlock, John Hogan Dr
Using Cognitive Mapping To Longitudinally Examine Political Brand Associations, Ewan Alexander Macdonald, Roger Sherlock, John Hogan Dr
Articles
This paper uses cognitive mapping techniques to understand how brand associations, an important aspect of political brand equity are formed, differ, and change, from the perspective of citizens, across the four largest Irish political parties between 2013 and 2016. The paper focuses in particular upon the strength, favourability and uniqueness of these brand associations. The results constitute a first attempt to longitudinally explore changing political brand associations through cognitive mapping techniques, using data generated with the participation of hundreds of citizens. Our findings suggest that this approach can contribute to our understanding of how and why political brand associations change …
Investigation Of Temperature Dependence Of Microfibre Coil Resonators, Yu Yin, Jibo Yu, Yuxuan Jiang, Shi Li, Jing Ren, Gerald Farrell, Elfed Lewis, Pengfei Wang
Investigation Of Temperature Dependence Of Microfibre Coil Resonators, Yu Yin, Jibo Yu, Yuxuan Jiang, Shi Li, Jing Ren, Gerald Farrell, Elfed Lewis, Pengfei Wang
Articles
The temperature-sensitive performance of a microfiber coil resonator (MCR) is thoroughly investigated. The MCR is fabricated by wrapping a microfiber on a PMMA rod coated with a UV-curable low refractive index epoxy. The temperature sensitivity is measured by investigating the correlation between the shift of the resonant wavelength and the surrounding temperature. It is determined that a range of parameters of the MCRs, including the gap between two adjacent rings, the diameter of the supporting rod, the number of rings, and the diameter of the microfiber, have a great influence on the temperature sensitivity of the MCRs. By optimizing the …
Investigation Of A Novel Sms Fiber Based Planar Multimode Waveguide And Its Sensing Performance, Xianfan Wang, Jiquan Zhang, Ke Tian, Shunbin Wang, Libo Yuan, Elfed Lewis, Gerald Farrell, Pengfei Wang
Investigation Of A Novel Sms Fiber Based Planar Multimode Waveguide And Its Sensing Performance, Xianfan Wang, Jiquan Zhang, Ke Tian, Shunbin Wang, Libo Yuan, Elfed Lewis, Gerald Farrell, Pengfei Wang
Articles
A novel, MMI-based all-fiber structure, which consists of two single-mode fibers and a multimode fiber polished on both sides, is described. The light propagation characteristics of this fiber structure, as well as its superior sensing performance, are analyzed theoretically by using the beam propagation method (BPM). This fiber structure demonstrates a significant spectral response to changes of the surrounding refractive index (RI), and the measured results exhibit good agreement with the predicted data. The measured average RI sensitivity is as high as 151.29 nm/RIU over an RI range from 1.3450 to 1.4050, when the polished depth is 30 µm on …
High-Sensitivity Salinity Sensor Based On Optical Microfiber Coil Resonator, Y. Yin, S. Li, J. Ren, Gerald Farrell, E. Lewis, Pengfei Wang
High-Sensitivity Salinity Sensor Based On Optical Microfiber Coil Resonator, Y. Yin, S. Li, J. Ren, Gerald Farrell, E. Lewis, Pengfei Wang
Articles
In recent years, salinity sensing has attracted much attention in potential areas ranging from marine monitoring, marine circulation, marine climate and environment protection in oceanography [1–4]. Generally, traditional methods of salinity measurement have been based on electronic methods (electrochemical) to detect the existence of chlorine ions of the seawater [5,6]. However, this method is affected greatly from the harsh environment, such as high corrosivity, extreme temperature and strong electromagnetic interference and is not used widely in micro scale due to its large size and complex structure. Electrochemical sensors are also prone to cross-sensitivity from and can even be damaged by …
Silica Gel Coated Spherical Micro Resonator For Ultra-High Sensitivity Detection Of Ammonia Gas Concentration In Air, Arun Mallik, Gerald Farrell, Dejun Liu, Vishnu Kavungal, Qiang Wu, Yuliya Semenova
Silica Gel Coated Spherical Micro Resonator For Ultra-High Sensitivity Detection Of Ammonia Gas Concentration In Air, Arun Mallik, Gerald Farrell, Dejun Liu, Vishnu Kavungal, Qiang Wu, Yuliya Semenova
Articles
A silica gel coated microsphere resonator is proposed and experimentally demonstrated for measurements of ammonia (NH3) concentration in air with ultra-high sensitivity. The optical properties of the porous silica gel layer change when it is exposed to low (parts per million (ppm)) and even ultra-low (parts per billion (ppb)) concentrations of ammonia vapor, leading to a spectral shift of the WGM resonances in the transmission spectrum of the fiber taper. The experimentally demonstrated sensitivity of the proposed sensor to ammonia is estimated as 34.46 pm/ppm in the low ammonia concentrations range from 4 ppm to 30 ppm using an optical …
The Role Of The Dendritic Growth Models Dimensionality In Predicting The Columnar To Equiaxed Transition (Cet), M. Seredyński, Marek Rebow, J. Banaszek
The Role Of The Dendritic Growth Models Dimensionality In Predicting The Columnar To Equiaxed Transition (Cet), M. Seredyński, Marek Rebow, J. Banaszek
Articles
The dendrite tip kinetics model accuracy relies on the reliability of the stability constant used, which is usually experimentally determined for 3D situations and applied to 2D models. The paper reports authors` attempts to cure the situation by deriving 2D dendritic tip scaling parameter for aluminium-based alloy: Al-4wt%Cu. The obtained parameter is then incorporated into the KGT dendritic growth model in order to compare it with the original 3D KGT counterpart and to derive two-dimensional and three-dimensional versions of the modified Hunt’s analytical model for the columnar-to-equiaxed transition (CET). The conclusions drawn from the above analysis are further confirmed through …
An Yb3+-Ho3+ Codoped Glass Microsphere Laser In The 2.0Μm Wavelength Regions, Angzhen Li, Jibo Yu, Meng Zhang, Xiaosong Lu, Jiquan Zhang, Elfed Lewis, Gerald Farrell, Pengfei Wang
An Yb3+-Ho3+ Codoped Glass Microsphere Laser In The 2.0Μm Wavelength Regions, Angzhen Li, Jibo Yu, Meng Zhang, Xiaosong Lu, Jiquan Zhang, Elfed Lewis, Gerald Farrell, Pengfei Wang
Articles
In this letter, an Yb 3+ -Ho 3+ codoped sol-gel silica microsphere lasing at around 2.0 μm is reported. The gain microsphere is fabricated by overlaying the 1.0 mol% Yb 3+ -0.2 mol% Ho 3+ codoped sol-gel solution on the surface of a pure silica microsphere and is then heated using a CO 2 laser. Using a traditional fiber taper-microsphere coupling method, we observe the single- and multi-mode microsphere laser outputs around 2.0 μm using a 980 nm laser diode as a pump source, with a low threshold pumping power of 14.7 mW. The ability to fabricate sol-gel codoped silica …
A High-Temperature Humidity Sensor Based On A Singlemode-Side Polished Multimode-Singlemode Fiber Structure, Xianfan Wang, Ke Tian, Libo Yuan, Elfed Lewis, Gerald Farrell, Pengfei Wang
A High-Temperature Humidity Sensor Based On A Singlemode-Side Polished Multimode-Singlemode Fiber Structure, Xianfan Wang, Ke Tian, Libo Yuan, Elfed Lewis, Gerald Farrell, Pengfei Wang
Articles
A relative humidity (RH) sensor based on a simple singlemode-side polished multimode-singlemode (SSPMS) fiber hybrid structure is investigated, which is capable of working over a relatively high-temperature range, at which many RH sensors based on moisture sensitive material coatings cannot operate. The beam propagation method is used to analyze the light transmission characteristics within the side polished multimode fiber (SPMMF) structure. Experimental results show that the SPMMF surface roughness has a significant influence on the sensor's humidity sensing performance, as a result of the adsorption and desorption of water molecules along the side polished surface. A higher surface roughness results …
Highly Sensitive Displacement Sensor Based On Composite Interference Established Within A Balloon-Shaped Bent Multimode Fiber Structure, Ke Tian, Gerald Farrell, Xianfan Wang, Elfed Lewis, Pengfei Wang
Highly Sensitive Displacement Sensor Based On Composite Interference Established Within A Balloon-Shaped Bent Multimode Fiber Structure, Ke Tian, Gerald Farrell, Xianfan Wang, Elfed Lewis, Pengfei Wang
Articles
A novel optical fiber displacement sensor based on composite interference established within a balloon-shaped bent multimode (BSBM) fiber structure is described and experimentally demonstrated. The BSBM fiber structure is realized by bending a straight single-mode–multimode–single-mode (SMS) fiber structure into a balloon shape using a length of capillary tube to fix the shape of the structure. Owing to the bend in the multimode waveguide, the original undistorted multimode interference pattern is changed, and an extra Mach–Zehnder interferometer is effectively introduced within the multimode fiber (MMF) section at a suitable bending radius. This established composite interference greatly improves the displacement sensing performance …
Versatile Soliton Emission From A Ws2 Mode-Locked Fiber Laser, Bo Guo, Shi Li, Ya-Xian Fan, Pengfei Wang
Versatile Soliton Emission From A Ws2 Mode-Locked Fiber Laser, Bo Guo, Shi Li, Ya-Xian Fan, Pengfei Wang
Articles
Recently, few-layer tungsten disulfide (WS2), as a shining 2D material, has been discovered to possess both the saturable absorption ability and large nonlinear refractive index. Here, we demonstrate versatile soliton pulses in a passively mode-locked fiber laser with a WS2-deposited microfiber. The few-layer WS2 is prepared by the liquid-phase exfoliation method and transferred onto a microfiber by the optical deposition method. Study found, the WS2-deposited microfiber can operate simultaneously as a mode-locker and a high-nonlinear device. In experiment, by further inserting the WS2 device into the fiber laser, besides the dual-wavelength soliton, noise-like soliton pulse, conventional soliton and its harmonic …
Fabrication And Characterization Of A Magnetized Metal-Encapsulated Fbg Sensor For Structural Health Monitoring, Sagar Jinachandran, Huijun Li, Jiangtao Xi, B. Gangadhara Prusty, Yuliya Semenova, Gerald Farrell, Ginu Rajan
Fabrication And Characterization Of A Magnetized Metal-Encapsulated Fbg Sensor For Structural Health Monitoring, Sagar Jinachandran, Huijun Li, Jiangtao Xi, B. Gangadhara Prusty, Yuliya Semenova, Gerald Farrell, Ginu Rajan
Articles
A novel means of metal packaging of a fiber Bragg grating (FBG) sensor using stainless steel and tin, together with high temperature resistant samarium cobalt (SmCo) magnet is proposed in this paper. The inclusion of high temperaturecapable SmCo magnets enable the metal packaging of the FBG sensor with magnetic capabilities. This packaged sensor can be placed in direct contact with the substrate structures such as iron pipelines and other ferromagnetic components without any adhesives, making them easily detachable and reusable. This is a significant improvement compared with other commercial fiber optic sensors which are, surface attached using epoxies or welded …
Dual-Stub Ka-Band Vivaldi Antenna With Integrated Bandpass Filter, Kansheng Yang, Manh-Ha Hoang, Xiulong Bao, Patrick Mcevoy, Max Ammann
Dual-Stub Ka-Band Vivaldi Antenna With Integrated Bandpass Filter, Kansheng Yang, Manh-Ha Hoang, Xiulong Bao, Patrick Mcevoy, Max Ammann
Articles
A dual-stub coplanar Vivaldi antenna with a parasitic element is presented. The dual-stub is coupled between the parasitic element and two tapered slots. The parasitic element shape and size is optimised. The use of slits on the outer edge of the ground plane is shown to provide control of beamwidth and maximum gain. A bandpass filter is used for performance control and sub-harmonic suppression.
Special Issue On The Use Of Accurate Tissue And Body Models In Rf And Mw Medical Applications, Giuseppe Ruvio, Marta Cavagnaro
Special Issue On The Use Of Accurate Tissue And Body Models In Rf And Mw Medical Applications, Giuseppe Ruvio, Marta Cavagnaro
Articles
No abstract provided.
A Simple All-Fiber Comb Filter Based On The Combined Effect Of Multimode Interference And Mach- Zehnder Interferometer, Guorui Zhou, Rahul Kumar, Qiang Wu, W. P. Ng, Richard Binns, Lalam Nageswara, Xinxiang Miao, Longfei Niu, Xiaodong Yuan, Yuliya Semenova, Gerald Farrell, Jinhui Yuan, Chongxiu Yu, Xinzhu Sang, Xiangjun Xin, Bo Liu, Haibing Lv, Yong Qing Fu
A Simple All-Fiber Comb Filter Based On The Combined Effect Of Multimode Interference And Mach- Zehnder Interferometer, Guorui Zhou, Rahul Kumar, Qiang Wu, W. P. Ng, Richard Binns, Lalam Nageswara, Xinxiang Miao, Longfei Niu, Xiaodong Yuan, Yuliya Semenova, Gerald Farrell, Jinhui Yuan, Chongxiu Yu, Xinzhu Sang, Xiangjun Xin, Bo Liu, Haibing Lv, Yong Qing Fu
Articles
A polarization-dependent all-fiber comb filter based on a combination effect of multimode interference and Mach-Zehnder interferometer was proposed and demonstrated. The comb filter was composed with a short section of multimode fiber (MMF) fusion spliced with a conventional single mode fiber on the one side and a short section of a different type of optical fiber on the other side. The second type of optical fiber is spliced to the MMF with a properly designed misalignment. Different types and lengths of fibers were used to investigate the influence of fiber types and lengths on the performance of the comb filter. …
Microdisk Resonator With Negative Thermal Optical Coefficient Polymer For Refractive Index Sensing With Thermal Stability, Tao Ma, Jinhui Yuan, Feng Li, Lei Sun, Zhe Kang, Binbin Yan, Qiang Wu, Xinzhu Sang, Heng Liu, Fang Wang, Bo Wu, Chongxiu Yu, Gerald Farrell
Microdisk Resonator With Negative Thermal Optical Coefficient Polymer For Refractive Index Sensing With Thermal Stability, Tao Ma, Jinhui Yuan, Feng Li, Lei Sun, Zhe Kang, Binbin Yan, Qiang Wu, Xinzhu Sang, Heng Liu, Fang Wang, Bo Wu, Chongxiu Yu, Gerald Farrell
Articles
In this paper, we propose a microdisk resonator with negative thermal optical coefficient (TOC) polymer for refractive index (RI) sensing with thermal stability. The transmission characteristics and sensing performances by using quasi-TE01 and quasi-TM01 modes are simulated by a three-dimensional finite element method. The influences of the TOC, RI, and thickness of the polymer on the sensing performances are also investigated. The simulation results show that the RI sensitivity Sn and temperature sensitivity ST with different polymers are in the ranges of 25.1-26 nm/RIU and 67.3-75.2 pm/K for the quasi-TE01 mode, and 94.5-110.6 nm/RIU and 1.2-51.3 pm/K for the quasi-TM01 …
Compound Glass Microsphere Resonator Devices, Jibo Yu, Elfed Lewis, Gerald Farrell, Pengfei Wang
Compound Glass Microsphere Resonator Devices, Jibo Yu, Elfed Lewis, Gerald Farrell, Pengfei Wang
Articles
In recent years, compound glass microsphere resonator devices have attracted increasing interest and have been widely used in sensing, microsphere lasers, and nonlinear optics. Compared with traditional silica resonators, compound glass microsphere resonators have many significant and attractive properties, such as high-Q factor, an ability to achieve high rare earth ion, wide infrared transmittance, and low phonon energy. This review provides a summary and a critical assessment of the fabrication and the optical characterization of compound glasses and the related fabrication and applications of compound glass microsphere resonators.
Low-Cost Multimode Patch Antenna For Dual Mimo And Enhanced Localization Use, Adam Narbudowicz, Max Ammann
Low-Cost Multimode Patch Antenna For Dual Mimo And Enhanced Localization Use, Adam Narbudowicz, Max Ammann
Articles
This paper proposes a simple, low-cost multi-mode patch antenna combining good MIMO performance with precise Angle of Arrival (AoA) estimation. The AoA is based on the monopulse antenna concept, however, unlike in radar applications, the necessity for complex circuitry is replaced by the intrinsic properties of even and odd resonant patch modes. This capability is advantageous for future “Internet of Things” antennas, embedded into low-cost and size-constrained devices. The envelope correlation coefficient, measured in an anechoic chamber, is below 1.5 %, ensuring good MIMO performance. An exemplary addition to localization algorithm exploiting antenna properties is demonstrated.
Passive Self-Interference Suppression For Single Channel Full-Duplex Operation, Adam Narbudowicz, Giuseppe Ruvio, Max Ammann
Passive Self-Interference Suppression For Single Channel Full-Duplex Operation, Adam Narbudowicz, Giuseppe Ruvio, Max Ammann
Articles
Full duplex radios have become a topic of increased interest in the wireless communications community. As part of this development, many efforts were directed to passively decrease the self-interference level at the antenna outputs. However, in many proposed solutions transmission and reception occur through different propagation channels. This paper demonstrates and quantifies the negative impact of channel differentiation on pivotal applications of full-duplex radio, such as cognitive radio. Antenna designs used for self-interference suppression in full-duplex radio architectures are analyzed. In order to ensure that transmission and reception occur within the same propagation channel, the use of the envelope correlation …
Optical Fiber Fresnel Reflection Sensor For Direct Detection Of The Solid-Liquid Phase Change In N-Octadecane, Wei Han, Marek Rebow, Dejun Liu, Yuliya Semenova, Qiang Wu Prof.
Optical Fiber Fresnel Reflection Sensor For Direct Detection Of The Solid-Liquid Phase Change In N-Octadecane, Wei Han, Marek Rebow, Dejun Liu, Yuliya Semenova, Qiang Wu Prof.
Articles
An all optical fiber Fresnel reflection sensor for detecting the solid–liquid phase change in n-octadecane is proposed and experimentally demonstrated. The sensor probe consists of a single-mode fiber with a cleaved end which is immersed in the material sample under test. As the n-octadecane changes from solid to liquid or from liquid to solid, its refractive index (RI) changes resulting in changes of the light power ratio reflected by the probe. Since the RI of n-octadecane during its phase transition changes discontinuously, inflection in the reflected light power ratio dependence indicates the phase change of the sample in the vicinity …
Multiband Slot-Loaded Dipole Antenna For Wlan And Lte-A Applications, Samir Salem Al-Bawri, Mohd. Faizal Jamlos, Ping Jack Soh, Syed Alwee Aljunid Syed Junid, Mohd Aminudin Jamlos, Adam Narbudowicz
Multiband Slot-Loaded Dipole Antenna For Wlan And Lte-A Applications, Samir Salem Al-Bawri, Mohd. Faizal Jamlos, Ping Jack Soh, Syed Alwee Aljunid Syed Junid, Mohd Aminudin Jamlos, Adam Narbudowicz
Articles
A multiband printed dipole antenna for wireless local area network (WLAN) and long-term evolution-advanced (LTEA) applications is investigated here. Its multiband characteristic is enabled by the Y-slot present in the upper arm of the dipole, while the antenna's dimensions are 0.08λo × 0.384λo at the lowest operating frequency. It features bandwidth of 14.6% centred at 2.4 GHz, and ∼30.5% centred at 5.5 GHz for WLAN operation. An additional bandwidth of 6.9% centred at 3.5 GHz supporting LTE-A applications is also featured. Besides being compact, the proposed antenna radiates omnidirectionally with a gain of up to 4.09 dBi. Simulations and measurements …
Optical Fibre Sensors For Monitoring Phase Transitions In Phase Changing Materials, Rahul Kumar, Wei Han, Dejun Liu, W. P. Ng, Binns, Richard Binns, Richard, Krishna K. Busawon, Yong Qing Fu, Zabih Ghassemlooy, Chris P. Underwood, Khamid Kh Mahkamov, Jinhui Yuan, Chongxiu Yu, Huazhong Shu, Xing Ao Li, Tuan Guo, Gerald Farrell, Yuliya Semenova, Qiang Wu
Optical Fibre Sensors For Monitoring Phase Transitions In Phase Changing Materials, Rahul Kumar, Wei Han, Dejun Liu, W. P. Ng, Binns, Richard Binns, Richard, Krishna K. Busawon, Yong Qing Fu, Zabih Ghassemlooy, Chris P. Underwood, Khamid Kh Mahkamov, Jinhui Yuan, Chongxiu Yu, Huazhong Shu, Xing Ao Li, Tuan Guo, Gerald Farrell, Yuliya Semenova, Qiang Wu
Articles
A platinum coated singlemode-multimode (SM) structure is investigated in this paper as an optical fibre sensor (OFS) to monitor the phase transition of a phase change material (PCM). Paraffin wax has been used as an example to demonstrate the sensor's performance and operation. Most materials have the same temperature but different thermal energy levels during the phase change process, therefore, sole dependency on temperature measurement may lead to an incorrect estimation of the stored energy in PCM. The output spectrum of the reflected light from the OFS is very sensitive to the bend introduced by the PCM where both liquid …
Formation And Development Of Nanometer-Sized Cybotactic Clusters In Bent-Core Nematic Liquid Crystalline Compounds, Yuri Panarin, Sithara P. Sreenilayam, Jagdish K. Vij, Anne Lehmann, Carsten Tschierske
Formation And Development Of Nanometer-Sized Cybotactic Clusters In Bent-Core Nematic Liquid Crystalline Compounds, Yuri Panarin, Sithara P. Sreenilayam, Jagdish K. Vij, Anne Lehmann, Carsten Tschierske
Articles
Two homologue achiral bent-core liquid crystals (LCs), BCN66 and BCN84, in their nematic phases are studied by dielectric spectroscopy in the frequency range 10 Hz–10 MHz. In each of these compounds, two relaxation processes are identified and assigned to (i) collective dynamics of molecules in nanometer-sized cybotactic clusters and (ii) individual molecular relaxations, in the ascending order of frequency of the probe field. The temperature and the bias electric field dependence of the dielectric strength and relaxation frequency for these processes are shown to give rise to sharpness in cluster boundaries, increased size and volume fraction in the LC nematic …
Simultaneous Measurement Of Displacement And Temperature Based On Baloon - Shaped Bent Smf Structure Incorporating An Lpg, Ke Tian, Wenlei Yang, Gerald Farrell, Elfed Lewis, Xianfan Wang, Pengfei Wang
Simultaneous Measurement Of Displacement And Temperature Based On Baloon - Shaped Bent Smf Structure Incorporating An Lpg, Ke Tian, Wenlei Yang, Gerald Farrell, Elfed Lewis, Xianfan Wang, Pengfei Wang
Articles
Abstract—A novel optical fibre sensor based on a balloon-shaped bent single-mode (BSBS) fibre structure incorporating a long-period grating (LPG) for simultaneous measurement of displacement and temperature is described and experimentally demonstrated. The sensor is fabricated by splicing a BSBS fibre structure formed Mach-Zehnder interferometer (MZI) with an LPG. Due to the interference dip which is formed by the BSBS fibre structure is sensitive to external displacement and temperature variation, while that formed by LPG only depends on temperature, displacement and temperature therefore can be unambiguously and simultaneously measured by this sensor. Experimental results show that this sensor offers a high …
Highly Sensitive Twist Sensor Based On Partially Silver Coated Hollow Core Fiber Structure, Dejun Liu, Rahul Kumar, Fangfang Wei, Wei Han, Arun Mallik, Jinhui Yuan, Chongxiu Yu, Feng Li, Zhengyong Liu, Hwa-Yaw Tam, Gerald Farrell, Yuliya Semenova, Qiang Wu
Highly Sensitive Twist Sensor Based On Partially Silver Coated Hollow Core Fiber Structure, Dejun Liu, Rahul Kumar, Fangfang Wei, Wei Han, Arun Mallik, Jinhui Yuan, Chongxiu Yu, Feng Li, Zhengyong Liu, Hwa-Yaw Tam, Gerald Farrell, Yuliya Semenova, Qiang Wu
Articles
Interferometer based on multiple beam interferences inside a hollow core fiber (HCF) structure (also known as an antiresonant reflecting optical waveguide) has been attracting interest of many researchers due to its periodic transmission spectrum containing high quality factor spectral dips. Functionalized HCF structures have been demonstrated for a wide range of applications in humidity, magnetic field, and biosensing. Here, we report a new application of the HCF-based structure with a partial silver coating layer for sensing of twist. It is configured by a fusion splicing a section of 4.5-mm long HCF between two standard single mode fibers (SMFs), followed by …
An Lcl-Filter Design With Optimum Total Inductance And Capacitance, Sampath Jayalath, Mohamed Moin Hanif
An Lcl-Filter Design With Optimum Total Inductance And Capacitance, Sampath Jayalath, Mohamed Moin Hanif
Articles
LCL-filter is among the best performing filters for grid-connected voltage source inverters. Designing of the filter parameters (grid-side and inverter-side inductors and capacitor), takes an iterative approach due to the coherence between the parameters and design requirements such as IEEE-519 Std for harmonic current limitations, reactive power compensation limit, and maximum allowable voltage drop across the filter to limit the switching losses. Most of the proposed LCL-filter optimization strategies emphasize on reducing the total inductance and losses of the filter while meeting the design requirements. There is less emphasis given on the capacitor selection and optimizing its value. Therefore, this …
Voltage Distortion Mitigation In A Distributed Generation-Integrated Weak Utility Network Via A Self-Tuning Filter-Based Dynamic Voltage Restorer, Samet Biricik, Shafiuzzaman Khadem, Soydan Redif, Malabika Basu
Voltage Distortion Mitigation In A Distributed Generation-Integrated Weak Utility Network Via A Self-Tuning Filter-Based Dynamic Voltage Restorer, Samet Biricik, Shafiuzzaman Khadem, Soydan Redif, Malabika Basu
Articles
The dynamic voltage restorer (DVR) is mainly used in a utility grid to protect sensitive loads from power quality problems, such as voltage sags and swells. However, the effectiveness of the DVR can wane under unbalanced grid voltage conditions. Recently, DVR control algorithms have been developed that enable the elimination of voltage harmonics in weak and distorted utility networks. This paper presents a modified control method for the DVR, which can (1) compensate the voltage swell and (2) eliminate the voltage harmonics in a combined utility condition consisting of voltage unbalance and harmonic distortion. A self-tuning filter (STF) is used …
The Different Stages Of Prpd Pattern For Positive Point To Plane Corona Driven By A Dc Voltage Containing A Ripple, Tobias Dezenzo, Thomas Betz, Andreas Schwarzbacher
The Different Stages Of Prpd Pattern For Positive Point To Plane Corona Driven By A Dc Voltage Containing A Ripple, Tobias Dezenzo, Thomas Betz, Andreas Schwarzbacher
Articles
The different phase resolved partial discharge patterns, which can be recognized when a positive dc voltage containing a ripple due to a half-wave rectification is used are presented in this paper. Results are given from corona onset to the appearance of breakdown streamers. The outcomes are five different patterns, which represent the four stages of positive corona and their transition zones. Three of them are clearly identifiable with respect to patterns from other discharge sources that have already been reported for dc voltages containing a ripple. For an assessment of pattern formation discharge pulses as recorded at the test object …
Design Of Event-Triggered Fault-Tolerant Control For Stochastic Systems With Time-Delays, Yi Gao, Yunji Li, Li Peng, Junyu Liu
Design Of Event-Triggered Fault-Tolerant Control For Stochastic Systems With Time-Delays, Yi Gao, Yunji Li, Li Peng, Junyu Liu
Articles
This paper proposes two novel, event-triggered fault-tolerant control strategies for a class of stochastic systems with state delays. The plant is disturbed by a Gaussian process, actuator faults, and unknown disturbances. First, a special case about fault signals that are coupled to the unknown disturbances is discussed, and then a fault-tolerant strategy is designed based on an event condition on system states. Subsequently, a send-on-delta transmission framework is established to deal with the problem of fault-tolerant control strategy against fault signals separated from the external disturbances. Two criteria are provided to design feedback controllers in order to guarantee that the …