High performance architecture design for large scale fibre-optic sensor arrays using distributed EDFAs and hybrid TDM/DWDM

A distributed amplified dense wavelength division multiplexing (DWDM) array architecture is presented for interferometric fibre optic sensor array systems. This architecture employs a distributed erbium doped fibre amplifier (EDFA) scheme to decrease the array insertion loss, and employs time division multiplexing (TDM) at each wavelength to increase the number of sensors that can be supported. The first experimental demonstration of this system is reported including results which show the potential for multiplexing and interrogating up to 4096 sensors using a single telemetry fibre pair with good system performance. The number can be increased to 8192 by using dual pump sources

OPINI MAHASISWA TENTANG TAYANGAN PODCAST

Penelitian ini berjudul Opini Mahasiswa Tentang Tayangan Podcast (Studi Deskriptif Kuantitatif Opini Mahasiswa Tentang Tayangan Podcast Deddy Corbuzier vs Andrew Kalaweit di program Studi Ilmu Komunikasi Fakultas Ilmu Sosial dan Ilmu Politik Universitas Sumatera Utara). Latar belakang penelitian ini melihat perkembangan Podcast yang membahas hal yang tidak menjadi trending topic menjadi hal yang menarik. Teori yang digunakan pada penelitian ini adalah teori S-O-R (Stimulus-Organism-Response) dengan menggunakan metode deskriptif kuantitatif. Mayoritas responden dalam penelitian ini menyatakan bahwa setelah menonton Podcast Deddy Corbuzier vs Andrew Kalaweit menambah pengetahuan bertahan hidup di hutan dengan persentase sebesar 85.9% atau sebanyak 73 orang responden. Selain itu mayoritas responden juga mengatakan bahwa setelah menonton tayangan Podcast Deddy Corbuzier vs Andrew Kalaweit mereka mengetahui bagaiamana cara menghadapi binatang buas yang dijumpai di hutan, dengan persentase 82.4% atau sebanyak 70 orang responden. Mayoritas responden juga menyatakan bahwa tayangan Podcast Deddy Corbuzier vs Andrew Kalaweit tidak memiliki dampak buruk bagi yang menontonnya dengan persentase sebesar 83.5% atau sebanyak 71 orang responden. Kesimpulannya, tayangan Podcast Deddy Corbuzier sangat baik dan layak untuk ditonton karena selain menghibur, tayangan Podcast tersebut mengajarkan kita banyak hal dari mulai pentingnya pendidikan diamanapun kita berada, bertahan hidup di hutan dan mengajarkan kita agar lebih peduli pada lingkungan

Model to predict the response of correlation spectroscopy gas detection systems for CH₄

We present a comprehensive model of a correlation spectroscopy gas sensor for CH4. Response and performance are predicted for typical fibre optic-coupled systems

Finite temperature effects in Coulomb blockade quantum dots and signatures of spectral scrambling

The conductance in Coulomb blockade quantum dots exhibits sharp peaks whose spacings fluctuate with the number of electrons. We derive the temperature-dependence of these fluctuations in the statistical regime and compare with recent experimental results. The scrambling due to Coulomb interactions of the single-particle spectrum with the addition of an electron to the dot is shown to affect the temperature-dependence of the peak spacing fluctuations. Spectral scrambling also leads to saturation in the temperature dependence of the peak-to-peak correlator, in agreement with recent experimental results. The signatures of scrambling are derived using discrete Gaussian processes, which generalize the Gaussian ensembles of random matrices to systems that depend on a discrete parameter -- in this case, the number of electrons in the dot.Comment: 14 pages, 4 eps figures included, RevTe

Full characterization and comparison of phase properties of narrow linewidth lasers operating in the C-band

We characterize and compare the performance of various commercially available lasers in terms of their absolute frequency stability, lineshape and linewidth, and frequency noise. The frequency stability, linewidth and lineshape are evaluated using an ‘optical ruler’ - a carrier-envelope stabilized optical comb. The frequency noise is measured over an extended spectral range starting from 2 Hz. The performed analysis gives data necessary when deciding which laser to use in a particular application

Universal Correlations of Coulomb Blockade Conductance Peaks and the Rotation Scaling in Quantum Dots

We show that the parametric correlations of the conductance peak amplitudes of a chaotic or weakly disordered quantum dot in the Coulomb blockade regime become universal upon an appropriate scaling of the parameter. We compute the universal forms of this correlator for both cases of conserved and broken time reversal symmetry. For a symmetric dot the correlator is independent of the details in each lead such as the number of channels and their correlation. We derive a new scaling, which we call the rotation scaling, that can be computed directly from the dot's eigenfunction rotation rate or alternatively from the conductance peak heights, and therefore does not require knowledge of the spectrum of the dot. The relation of the rotation scaling to the level velocity scaling is discussed. The exact analytic form of the conductance peak correlator is derived at short distances. We also calculate the universal distributions of the average level width velocity for various values of the scaled parameter. The universality is illustrated in an Anderson model of a disordered dot.Comment: 35 pages, RevTex, 6 Postscript figure

Measuring cerebrovascular autoregulation in preterm infants using near-infrared spectroscopy: an overview of the literature

Introduction: The preterm born infant’s ability to regulate its cerebral blood flow (CBF) is crucial in preventing secondary ischemic and hemorrhagic damage in the developing brain. The relationship between arterial blood pressure (ABP) and CBF estimates, such as regional cerebral oxygenation as measured by near-infrared spectroscopy (NIRS), is an attractive option for continuous non-invasive assessment of cerebrovascular autoregulation. Areas covered: The authors performed a literature search to provide an overview of the current literature on various current clinical practices and methods to measure cerebrovascular autoregulation in the preterm infant by NIRS. The authors focused on various aspects: Characteristics of patient cohorts, surrogate measures for cerebral perfusion pressure, NIRS devices and their accompanying parameters, definitions for impaired cerebrovascular autoregulation, methods of measurements and clinical implications. Expert commentary: Autoregulation research in preterm infants has reported many methods for measuring autoregulation using different mathematical models, signal processing and data requirements. At present, it remains unclear which NIRS signals and algorithms should be used that result in the most accurate and clinically relevant assessment of cerebrovascular autoregulation. Future studies should focus on optimizing strategies for cerebrovascular autoregulation assessment in preterm infants in order to develop autoregulation-based cerebral perfusion treatment strategies

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio