Searched for: subject%3A%22gratings%22
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Rajabzadeh, Aydin (author), Hendriks, R.C. (author), Heusdens, R. (author), Groves, R.M. (author)
Fibre Bragg grating sensors have gained a lot of attention in damage detection and strain measurement applications in the past few decades. These applications include matrix crack detection and delamination tip monitoring in composite structures, crack detection in concrete and civil engineering structures and etc. The damage localisation...
conference paper 2019
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Schenatoa, Luca (author), Aguilar Lopez, J.P. (author), Galtarossa, Andrea (author), Pasutoa, Alessandro (author), Bogaard, T.A. (author), Palmieri, Luca (author)
We present the design and field test of a rugged FBG sensor prototype for high-sensitivity measurement of underground water level. Pressure sensors have many fields of application, ranging from environmental monitoring to the oil and gas industry. In particular, pressure sensors can be used to monitor the stability of dikes and embankments by...
conference paper 2019
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Rajabzadeh, Aydin (author), Heusdens, R. (author), Hendriks, R.C. (author), Groves, R.M. (author)
In this letter, we propose a method for estimating the length of single-mode fiber Bragg grating type sensors with high accuracy. Our method is based on calculating the maximum oscillation frequency of the side-lobes of the FBG reflection spectrum. We show that this frequency is independent of the stress field to which the sensor is subjected...
journal article 2019
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Loef, Thomas (author)
Thin-film silicon solar cells make use of relatively thin layers of active material compared to wafer based solar cells. The main advantage of thin absorber layers is the possibility to fabricate flexible solar cells. However, due to limited absorber layer thickness and weak absorption coefficients at long wavelengths, light management...
master thesis 2018
document
Rajabzadeh, Aydin (author), Heusdens, R. (author), Hendriks, R.C. (author), Groves, R.M. (author)
In the past few decades, fibre Bragg grating (FBG) sensors have gained a lot of attention in the field of distributed point strain measurement. One of the most interesting properties of these sensors is the presumed linear relationship between the strain and the peak wavelength shift of the FBG reflected spectra. However, subjecting sensors to a...
journal article 2018
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Rajabzadeh, Aydin (author), Hendriks, R.C. (author), Heusdens, R. (author), Groves, R.M. (author)
In this paper, we used the efficient formulation of the approximated transfer matrix model (ATMM) for the analysis of fibre Bragg grating (FBG) sensors' response under anti-symmetrical strain fields. Exploiting the flexible representation of the transfer matrices in this new model, we will analytically prove that any sort of anti-symmetrical...
conference paper 2018
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Vismara, R. (author), Dane Linssen, N. P. (author), Wang, Ken X. (author), Fan, Shanhui (author), Isabella, O. (author), Zeman, M. (author)
We present a modelling study of thin silicon based solar cells endowed with periodic and decoupled front/back textures. After careful optimization, the proposed device models exhibit absorption beyond the Lambertian light trapping limit for a wide range of light angles of incidence. The advanced light management scheme is applied to (nano...
conference paper 2018
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van den Bercken, Vincent (author)
Using Fiber Bragg Grating (FBG) sensors in rolling element bearings is a novel way of monitoring bearings. During prototype testing, differences between sensor readouts were observed, leading to the research question: “What causes the observed differences in the strain distribution from sensor to sensor in a rolling element bearing equipped with...
master thesis 2017
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Miller, Seirgei (author), Chakraborty, Joyraj (author), van der Vegt, Jurian (author), Brinkerink, Daan (author), Erkens, S. (author), Liu, X. (author), Anupam, K. (author), Sluer, Berwich (author), Mohajeri, Mohamad (author)
The Fibre Bragg Gratings (FBG) technology based on integrated photonics, offers specific benefits including thermal mapping, damage detection, shape- and distributed sensing. This makes it useful for determining pavement behaviour during extreme weather conditions e.g. freeze-thaw cycles when harsh winter conditions could damage the asphalt...
journal article 2017
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Rajabzadeh, Aydin (author), Hendriks, R.C. (author), Heusdens, R. (author), Groves, R.M. (author)
This paper describes a new method for the classification and identification of two major types of defects in composites, namely delamination and matrix cracks, by classification of the spectral features of fibre Bragg grating (FBG) signals. In aeronautical applications of composites, after a damage is detected, it is very useful to know the...
conference paper 2017
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Rajabzadeh, Aydin (author), Groves, R.M. (author), Hendriks, R.C. (author), Heusdens, R. (author)
In this paper the behaviour of fibre Bragg grating (FBG) sensors under non-uniform strain distributions was analysed. Using the fundamental matrix approach, the length of the FBG sensor was discretised, with each segment undergoing different strain values. FBG sensors that are embedded inside composites, also undergo such non-uniform strain...
conference paper 2017
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Vismara, R. (author), Isabella, O. (author), Zeman, M. (author)
We present the optical investigation of a novel back-contacted architecture for solar cells based on a thin barium (di)silicide (BaSi<sub>2</sub>) absorber. First, through the analysis of absorption limits of different semiconducting materials, we show the potential of BaSi<sub>2</sub> for photovoltaic applications. Then, the proposed back...
journal article 2017
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Ushakova, K. (author)
doctoral thesis 2016
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Snel, T.W. (author)
An ventilated composite shallow foundation for subsea structures is designed. The ventilated grating configuration improves operability of the installation through the splash zone. By penetrating into the soil, the foundation provides sufficient bearing capacity due to the additional generated skin friction. Furthermore, the seabed landing is...
master thesis 2016
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Isabella, O. (author), Vismara, R. (author), Ingenito, A. (author), Rezaei, N. (author), Zeman, M. (author)
The optical analysis of optically-textured and electrically-flat ultra-thin crystalline silicon (c-Si) slabs is presented. These slabs were endowed with decoupled front titanium-dioxide (TiO2) / back silicon-dioxide (SiO2) dielectric textures and were studied as function of two types of back reflectors: standard silver (Ag) and dielectric...
journal article 2016
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Sales, Morten (author), Plomp, J. (author), Habicht, Klaus (author), Tremsin, Anton (author), Bouwman, W.G. (author), Strobl, Markus (author)
Spin-Echo Modulated Small Angle Neutron Scattering (SEMSANS) in Time-of-Flight (ToF) mode has been shown to be a promising technique for measuring (very) small angle neutron scattering (SANS) signals and performing quantitative Dark-Field Imaging (DFI), i.e., SANS with 2D spatial resolution. However, the wavelength dependence of the...
journal article 2016
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Van Reekum, R.B. (author)
Pressure locked gratings have many uses, both on land and at sea. This is mainly due to the high degree of flexibility in dimensions and load bearing capacity. Despite the many uses in our surroundings, the term pressure locked grating is unknown to many. This term refers to the way in which the most important connection in pressure locked...
master thesis 2015
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Bentum, Mark J (author), Lager, I.E. (author), Bosma, S. (author), Bruinsma, W.P. (author), Hes, R.P. (author)
The impact of the fluctuations in the locations of elementary radiators on the radiation properties of three-dimensional (3D) array antennas is studied. The principal radiation features (sidelobes level, beam squint) are examined based on illustrative examples. Some atypical behaviours, that are specific to 3D arrays, are highlighted. The effect...
conference paper 2015
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Kumar, N. (author)
The electronics which makes our lives easier like mobiles, computers, digital cameras contain chips with very small semiconductor components like transistors. When transistors can be made even smaller, the chip can accommodate a larger number of components, which gives more processing capacity, resulting in a faster device with an increased...
doctoral thesis 2014
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Vismara, R. (author)
Advanced texturization is a promising approach to increase the performance of thin-film solar cells. Currently, light trapping schemes implemented in state-of-the-art devices utilize randomly textured interfaces to increase their optical performance. Periodic gratings, however, have the potential to outperform their random counterparts and are...
master thesis 2014
Searched for: subject%3A%22gratings%22
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