Search results for "NOISE"
showing 10 items of 1375 documents
A case study to the Evaluation of Global Environmental Quality, concerning thermal, acoustic and atmospheric conditions of urban areas
2013
In this paper we propose an operative procedure aimed at assessing and check the global environmental quality in the urban areas. This methodology is set up by using an ergonomic approach that analyses the interaction man-environment in terms of cause-effect and uses information and data from various sources contributing to the formation of discomfort degrees.[1-2] The representation technique by normo-grams is used for showing some applications executed along the urban territory of Palermo and allows to evaluate very simply all the parameters involved in human comfort. This paper is divided in 5 sections, after the introduction in section 2 a review of the principal simple and complex inde…
“Hyperethnicity” and Ethnic Scenarios in White Noise by Don DeLillo
2021
The present article aims at analyzing the reshaping of the Italian American cultural heritage in Don DeLillo’s White Noise. Drawing on the concept of hyperreality as construed by Jean Baudrillard, the notion of hyperethnicity proves to be an efficient tool for a thorough exam of the transformation of the crucial Italian American topoi — i.e, ethnic signifiers such as the conception of the family, the theme of the household, and the concept of serietà — in the novel White Noise by Don DeLillo. Analyzing the signs of italianità in novels by Don DeLillo, Fred Gardaphé hypothesizes that the writer enacts a “masquerade” of his cultural identity, encoding in this manner ethnic “traces” into his o…
Biophysical parameter estimation with adaptive Gaussian Processes
2009
We evaluate Gaussian Processes (GPs) for the estimation of biophysical parameters from acquired multispectral data. The standard GP formulation is used, and all hyperparameters (kernel parameters and noise variance) are optimized by maximizing the marginal likelihood. This gives rise to a fully-adaptive GP to data characteristics, both in terms of signal and noise properties. The good numerical results in the estimation of oceanic chlorophyll concentration and leaf membrane state confirm GPs as adequate, alternative non-parametric methods for biophysical parameter estimation. GPs are also analyzed by scrutinizing the predictive variance, the estimated noise variance, and the relevance of ea…
Seismic Network Evaluation through Simulation: An Application to the Italian National Seismic Network
2011
Abstract A properly organized seismic network is a valuable tool for monitoring seismic zones and assessing seismic hazards. In this paper we propose a new method (seismic network evaluation through simulation, SNES) to evaluate the performance of hypocenter location of a seismic network. The SNES method gives, as a function of magnitude, hypocentral depth, and confidence level, the spatial distribution of the number of active stations in the location procedure and their relative azimuthal gaps, along with confidence intervals in hypocentral parameters. The application of the SNES method also permits evaluation of the magnitude of completeness ( M C ), the background noise levels at the sta…
Interval Length Analysis in Multi Layer Model
2009
In this paper we present an hypothesis test of randomness based on the probability density function of the symmetrized Kulback-Leibler distance estimated, via a Monte Carlo simulation, by the distributions of the interval lengths detected using the Multi-Layer Model (MLM). The $MLM$ is based on the generation of several sub-samples of an input signal; in particular a set of optimal cut-set thresholds are applied to the data to detect signal properties. In this sense MLM is a general pattern detection method and it can be considered a preprocessing tool for pattern discovery. At the present the test has been evaluated on simulated signals which respect a particular tiled microarray approach …
The Impact of Macroeconomic Variables on Corporate Performance - What Shareholders Ought to Know?
2002
Increased integration and growing macroeconomic fluctuations require more attention to be paid to the link between the "noise" that these fluctuations represent and the company's own development. For many reasons management must weed out the effects of the "noise" so as to obtain a clear picture of the long-term sustainable profits, and thus a picture of how the company's intrinsic competitiveness is fostered. An understanding of the effects of the fluctuations also provides the basis for risk assessment. How far, then, should this "new" view of corporate performance be extended to outsider shareholders? Current reporting practice does not provide these shareholders with an adequate idea of…
Experimental investigation of the kink effect and the low frequency noise properties in pseudomorphic HEMT’s
2005
The kink effect in low-noise pseudomorphic (AlGaAs/InGaAs) HEMT's has been examined in detail by investigating the steady-state and pulsed I-V characteristics, the behavior of the output conductance dispersion and the performance of the gate leakage current to understand its origin. No clear evidence of impact ionization occurrence in the InGaAs channel at kink bias conditions (V-DS.kink = 1.5 V) has been found, thus suggesting that the predominant mechanism should be attributed to trap-related phenomena. A significant rise of the gate current has been found at very high drain voltages (far from V-DS.kink) associated with low drain current values which is probably due to impact ionization o…
Robust Fault Detection of Linear Uncertain Time-Delay Systems Using Unknown Input Observers
2013
This paper deals with the problem of fault detection for linear uncertain time-delay systems. The proposed method for Luenberger observers is developed for unknown input observers (UIOs), and a novel procedure for the design of residual based on UIOs is presented. The design procedure is carried out based on the ${H}_{\infty }$ model matching approach which minimizes the difference between generated residuals by the optimal observer and those by the designed observer in the presence of uncertainties. The optimal observer is designed for the ideal system and works so that the fault effect is maximized while the exogenous disturbances and noise effects are minimized. This observer can give di…
Quantitative comparison of new image processing methods for volumetric analysis of left ventricular contrast echocardiograms
2003
An effort has been made to develop image processing methods which allow a definite and precise tracking of the borderline of the ventricle in two-dimensional echocardiograms. Experience is reported with two new methods, which are based on the gray-level rise (GL) and the signal-to-noise ratio (SNR) in combined heart-phase-triggered image series. A quantitative comparison of these time-series methods is presented with respect to the interpretation of a single native image (noncontrast image), a single contrast-material image, the corresponding subtraction image, and the corresponding color superposition image. The comparison is based on the calculation of the ejection fraction using the abov…
Image Processing Techniques For the Detection and Classification of Man Made Objects in Side-Scan Sonar Images
2011
This is a review chapter that surveys past work in, and the recent status of image processing and other related techniques involved in the detection and classification of man made objects in side scan sonar images. Side scan sonar is a readily, available and cheap device which has found increasing applications, specially for military purposes such as Computer Aided Detection (CAD) and Classification (CAC) of mines. Therefore the main focus of the chapter is on this topic. The list of references is sufficiently complete to include most past and recent publications in the open refereed literature. Although side scan sonar displays many features similar to an optical sensor from a purely image…