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Full-Text Articles in Engineering
Load-Adjusted Prediction For Proactive Resource Management And Video Server Demand Profiling, Obinna Izima, Ruairí De Fréin
Load-Adjusted Prediction For Proactive Resource Management And Video Server Demand Profiling, Obinna Izima, Ruairí De Fréin
Articles
To lower costs associated with providing cloud resources, a network manager would like to estimate how busy the servers will be in the near future. This is a necessary input in deciding whether to scale up or down computing requirements. We formulate the problem of estimating cloud computational requirements as an integrated framework comprising of a learning and an action stage. In the learning stage, we use Machine Learning (ML) models to predict the video Quality of Delivery (QoD) metric for cloud-hosted servers and use the knowledge gained from the process to make resource management decisions during the action stage. …
Source Separation Approach To Video Quality Prediction In Computer Networks, Ruairí De Fréin
Source Separation Approach To Video Quality Prediction In Computer Networks, Ruairí De Fréin
Articles
Time-varying loads introduce errors in the estimated model parameters of service-level predictors in Computer Networks. A load-adjusted modification of a traditional unadjusted service-level predictor is contributed, based on Source Separation (SS). It mitigates these errors and improves service-quality predictions for Video-on-Demand (VoD) by :6 to 2dB.
A Simple Ultrasensitive Displacement Sensor Based On A High Bend Loss Single-Mode Fibre And A Ratiometric Measurement System, Pengfei Wang, Gilberto Brambilla, Yuliya Semenova, Qiang Wu, Gerald Farrell
A Simple Ultrasensitive Displacement Sensor Based On A High Bend Loss Single-Mode Fibre And A Ratiometric Measurement System, Pengfei Wang, Gilberto Brambilla, Yuliya Semenova, Qiang Wu, Gerald Farrell
Articles
A Hybrid Highly Birefringent Fiber Optic Sensing System For Simultaneous Strain And Temperature Measurement, Piotr Lesiak, Ginu Rajan, Yuliya Semenova, Gerald Farrell, Anna Boczkowska, Andrzej Domanski, Tomasz Wolinkski
A Hybrid Highly Birefringent Fiber Optic Sensing System For Simultaneous Strain And Temperature Measurement, Piotr Lesiak, Ginu Rajan, Yuliya Semenova, Gerald Farrell, Anna Boczkowska, Andrzej Domanski, Tomasz Wolinkski
Articles
A novel hybrid fiber optic sensor based on integration of polarimetric fiber sensors for simultaneous strain and temperature measurement is presented in this paper. Two types of polarimetric fibers are used: a side-hole fiber and a polarization maintaining photonic crystal fiber. The disadvantage of each sensor type can be overcome by using the sensors in a complementary manner to measure temperature independently from average strain.
A Hybrid Fiber Optic Sensing System For Simultaneous Strain And Temperature Measurement And Its Application, Ginu Rajan, Karolina Milenko, Piotr Lesiak, Yuliya Semenova, Anna Boczkowska, Manjusha Ramakrishnan, Kazimierz Jedrzejewski, Andrzej Domanski, Tomasz Wolinski, Gerald Farrell
A Hybrid Fiber Optic Sensing System For Simultaneous Strain And Temperature Measurement And Its Application, Ginu Rajan, Karolina Milenko, Piotr Lesiak, Yuliya Semenova, Anna Boczkowska, Manjusha Ramakrishnan, Kazimierz Jedrzejewski, Andrzej Domanski, Tomasz Wolinski, Gerald Farrell
Articles
A hybrid fiber optic sensor by integrating polarimetric fiber sensors and fiber Bragg grating sensors for simultaneous strain and temperature measurement is presented in this paper. Two types of polarimetric fiber sensors are used; a Panda fiber and a polarization maintaining photonic crystal fiber. The polarimetric strain sensors give the average strain and temperature information, while the fiber Bragg grating sensors give localized strain information. Two applications of the proposed configuration are also demonstrated in this paper. In the composite materials three fiber sensors are used while for other engineering applications a temperature insensitive polarimetric fiber sensor can be used …
Study Of The Effect Of Source Signal Bandwidth On Ratiometric Wavelength Measurement, Qiang Wu, Yuliya Semenova, Ginu Rajan, Pengfei Wang, Gerald Farrell
Study Of The Effect Of Source Signal Bandwidth On Ratiometric Wavelength Measurement, Qiang Wu, Yuliya Semenova, Ginu Rajan, Pengfei Wang, Gerald Farrell
Articles
We derive an analytic equation for a ratiometric wavelength measurement system and analyze the influence of the optical source signal bandwidth. Our investigation shows that in a particular optical sensing system, the higher the bandwidth of the optical signal, the better resolution the system will achieve. Experiments based on two types of optical signals (output signal of a tunable laser and a fiber Bragg grating) were carried out, and experimental results verified both the simulation results and the theoretical analysis.
Sms Fibre Structure For Temperature Measurement Using A Simple Intensity-Based Interrogation System, Agus Hatta, Ginu Rajan, Yuliya Semenova, Gerald Farrell
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.
Digital Camera Photographing In Measuring Propagation Loss Properties Of Ion2exchange Planar Optical Waveguides, Ling-Hua Jia, Feng Qiu, Jian Ying, Ti Yun-Jiang, Jie Z|Heng, Pengfei Wang, Gerald Farrell
Digital Camera Photographing In Measuring Propagation Loss Properties Of Ion2exchange Planar Optical Waveguides, Ling-Hua Jia, Feng Qiu, Jian Ying, Ti Yun-Jiang, Jie Z|Heng, Pengfei Wang, Gerald Farrell
Articles
The digital photographs of propagation lines of ion-exchange planar glass optical waveguides were taken by a common digital camera.According to the profile of light intensity of propagation lines,the attenuation curves were fitted and the propagation losses of the waveguides were calculated.The waveguides were treated by annealing process,and propagation losses properties were studied before and after annealing,respectively.The results show that the loss of waveguide increases with the mode.The loss in 0 mode decreases from 2.148 9 dB·cm－1 to 0.746 0 dB·cm－1.
Resolution Investigation Of A Ratiometric Wavelength Measurement System, Qian Wang, Ginu Rajan, Pengfei Wang, Gerald Farrell
Resolution Investigation Of A Ratiometric Wavelength Measurement System, Qian Wang, Ginu Rajan, Pengfei Wang, Gerald Farrell
Articles
Theoretical analysis and experimental investigations are presented on the resolution of a ratiometric wavelength measurement system. Theoretical modeling indicates that the resolution of a ratiometric wavelength measurement system is determined by the signal-to-noise ratio of the input signal and the noise of the photodetectors associated with optical-to-electronic conversion. For experimental verification, a ratiometric system employing a macrobending standard single-mode fiber is developed and corresponding results are in good agreement with the theoretical prediction.
Macrobending Fiber Loss Filter, Ratiometric Wavelength Measurement And Application, Qian Wang, Ginu Rajan, Gerald Farrell, Pengfei Wang, Yuliya Semenova, Thomas Freir
Macrobending Fiber Loss Filter, Ratiometric Wavelength Measurement And Application, Qian Wang, Ginu Rajan, Gerald Farrell, Pengfei Wang, Yuliya Semenova, Thomas Freir
Articles
A macrobending standard single-mode fibre (SMF28) is optimized as an edge filter, with the optimal bending radius and length determined according to the bend loss and polarization sensitivity of the bending fibre. An all-fibre ratiometric wavelength system is built and calibrated. The system's accuracy and resolution is discussed with the influence of noise of input signal and photodetectors. Finally, the ratiometric system is employed for the demodulation of FBG strain sensing.
Effect Of Polarisation-Dependent Loss On The Performance Accuracy Of A Ratiometric Wavelength Measurement System, Ginu Rajan, Qian Wang, Yuliya Semenova, Gerald Farrell, Pengfei Wang
Effect Of Polarisation-Dependent Loss On The Performance Accuracy Of A Ratiometric Wavelength Measurement System, Ginu Rajan, Qian Wang, Yuliya Semenova, Gerald Farrell, Pengfei Wang
Articles
The polarisation-dependent loss (PDL) of a ratiometric wavelength measurement system and its influence on system's accuracy are investigated theoretically and experimentally. The PDL of a ratiometric system and the corresponding power ratio fluctuation is modelled, from which the accuracy of the measured wavelength can be estimated. An all-fibre wavelength measurement system is built to allow comparison of modelled and actual results. The measured ratio variation lies within the estimated limits. The measured wavelength error reaches about 1.41 plusmn 0.09 nm at 1550 nm in the demonstrated example (with an edge filter of average slope 0.22 dB/nm), which indicates the significant …
Low-Cost Wavelength Measurement Based On A Macrobending Single-Mode Fiber, Qian Wang, Gerald Farrell, Thomas Freir, Ginu Rajan, Pengfei Wang
Low-Cost Wavelength Measurement Based On A Macrobending Single-Mode Fiber, Qian Wang, Gerald Farrell, Thomas Freir, Ginu Rajan, Pengfei Wang
Articles
A low-cost all-fiber wavelength measurement technique is proposed and demonstrated. A macrobending standard single-mode fiber is developed as an edge filter with an optimal design and simple surface processing. A ratiometric wavelength measurement system employing the developed macrobending fiber filter demonstrates a resolution of ∼10 pm in a wavelength range from 1500 to 1560 nm with ease of assembly and calibration.
Low-Cost Wavelength Measurement Based On A Macrobending Single-Mode Fiber, Qian Wang, Gerald Farrell, Thomas Freir, Ginu Rajan, Pengfei Wang
Low-Cost Wavelength Measurement Based On A Macrobending Single-Mode Fiber, Qian Wang, Gerald Farrell, Thomas Freir, Ginu Rajan, Pengfei Wang
Articles
A low-cost all-fiber wavelength measurement technique is proposed and demonstrated. A macrobending standard single-mode fiber is developed as an edge filter with an optimal design and simple surface processing. A ratiometric wavelength measurement system employing the developed macrobending fiber filter demonstrates a resolution of∼10 pmin a wavelength range from1500to1560 nmwith ease of assembly and calibration.
Study Of Transmission Response Of Edge Filters Employed In Wavelength Measurements, Qian Wang, Gerald Farrell, Thomas Freir
Study Of Transmission Response Of Edge Filters Employed In Wavelength Measurements, Qian Wang, Gerald Farrell, Thomas Freir
Articles
The ratiometric wavelength-measurement system is modeled and an optimal design of transmission response of the employed edge filter is demonstrated in the context of a limited signal-to-noise ratio of the signal source. The corresponding experimental investigation is presented. The impact of the limited signal-to-noise ratio of the signal source on determining the optimal transmission response of edge filters for a wavelength-measurement application is shown theoretically and experimentally.