Browsing Electrical and Computer Engineering by Title
Now showing items 1406-1425 of 1879
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QEPAS based ppb-level detection of CO and N2O using a high power CW DFB-QCL
(2013-01-14)An ultra-sensitive and selective quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor platform was demonstrated for detection of carbon monoxide (CO) and nitrous oxide (N2O). This sensor used a stateof- the art ... -
QoS-driven server migration for Internet data centers
(2002)Many organizations have chosen to host Internet applications at Internet Data Centers (IDCs) located near network access points of the Internet to take advantage of their high availability, large network bandwidths and low ... -
QRD-QLD searching based sphere detection for emerging MIMO downlink OFDM receivers
(2008-11-01)In this paper, a detection algorithm with parallel partial candidate-search algorithm is presented. Two fully independent partial search processes are simultaneously employed for two groups of transmit antennas based on ... -
Quantifying spectral changes experienced by plasmonic nanoparticles in a cellular environment to inform biomedical nanoparticle design
(2014)Metal nanoparticles (NPs) scatter and absorb light in precise, designable ways, making them agile candidates for a variety of biomedical applications. When NPs are introduced to a physiological environment and interact ... -
Quantitative evaluation of performance of three-dimensional printed lenses
(2017)We present an analysis of the shape, surface quality, and imaging capabilities of custom three-dimensional (3-D) printed lenses. 3-D printing technology enables lens prototypes to be fabricated without restrictions on ... -
Quantization of Sparse Representations
(2007-01-16)Compressive sensing (CS) is a new signal acquisition technique for sparse and compressible signals. Rather than uniformly sampling the signal, CS computes inner products with randomized basis functions; the signal is then ... -
Quantum cascade laser based spectroscopic sensor systems for trace gas detection
(2014-03-31)Quantum cascade laser (QCL) based spectroscopic techniques are useful for the quantitative detection and monitoring of molecular trace gas species in the mid-infrared spectral region. Sensitive and selective trace gas ... -
Quantum Cascade Laser Spectrometer for Trace-Gas Detection of Exhaled Carbonyl Sulfide
(2004-05-01)Simultaneous concentration measurements of echaled carbonyl sulfide and carbon dioxide were demonstrated using a pulsed quantum cascade laser based gas sensor. This sensor has potential applications in biomedical diagnostics ... -
Quantum cascade laser-based multipass absorption system for hydrogen peroxide detection
(2015)Hydrogen peroxide (H2O2) is a relevant molecular trace gas species, that is related to the oxidative capacity of the atmosphere, the production of radical species such as OH, the generation of sulfate aerosol via oxidation ... -
Quartz enhanced photoacoustic H2S gas sensor based on a fiber-amplifier source and a custom tuning fork with large prong spacing
(2015)A quartz enhanced photoacoustic spectroscopy (QEPAS) sensor, employing an erbium-doped fiber amplified laser source and a custom quartz tuning fork (QTF) with its two prongs spaced ∼800 μm apart, is reported. The sensor ... -
Quartz Enhanced Photoacoustic Spectroscopy Based Trace Gas Sensors Using Different Quartz Tuning Forks
(2015)A sensitive trace gas sensor platform based on quartz-enhanced photoacoustic spectroscopy (QEPAS) is reported. A 1.395 μm continuous wave (CW), distributed feedback pigtailed diode laser was used as the excitation source ... -
Quartz-enhanced conductance spectroscopy for nanomechanical analysis of polymer wire
(2015)Quartz-enhanced conductance spectroscopy is developed as an analytical tool to investigate dynamic nanomechanical behaviors of polymer wires, in order to determine the glass transition temperature (Tg). A polymethyl ... -
Quartz-enhanced photoacoustic spectroscopy exploiting tuning fork overtone modes
(2015)We report on a quartz-enhanced photoacoustic sensor (QEPAS) based on a custom-made quartz tuning fork (QTF) to operate in both the fundamental and the first overtone vibrational mode resonances. The QTF fundamental mode ... -
Quartz-Enhanced Photoacoustic Spectroscopy: A Review
(2014)A detailed review on the development of quartz-enhanced photoacoustic sensors (QEPAS) for the sensitive and selective quantification of molecular trace gas species with resolved spectroscopic features is reported. The basis ... -
Quasi-Circular Rotation Invariance in Image Denoising
(1999-10-20)This paper studies a new method for wavelet-based image denoising which is translation invariant (TI) <b>and</b> rotation invariant (RI). These invariances are crucial in image denoising and, more generally, may play ... -
Quaternion Wavelets for Image Analysis and Processing
(2004-10-01)Using the concepts of two-dimensional Hubert transform and analytic signal, we construct a new quaternion wavelet transform (QWT). The QWT forms a tight frame and can be efficiently computed using a-2-D dual-tree filter ... -
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A Radially-Gaussian, Signal-Dependent Time-Frequency Representation
(1991-04-01)An optimization formulation for designing signal-dependent kernels that are based on radially Gaussian functions is presented. The method is based on optimality criteria and is not ad hoc. The procedure is automatic. The ... -
Random Filters for Compressive Sampling and Reconstruction
(2006-05-01)We propose and study a new technique for efficiently acquiring and reconstructing signals based on convolution with a fixed FIR filter having random taps. The method is designed for sparse and compressible signals, i.e., ...
