Search results for "Correlation"
showing 10 items of 2282 documents
Frequency mapping in dynamic light emission with wavelet transform
2013
International audience; Dynamic photon emission microscopy is an e cient tool to analyse today's integrated circuit. Nevertheless, the reduction of transistor's dimensions leads to more complex acquisitions where many spots can be seen. A frequency characterization of the whole acquired area can help to have a better understanding of it. With that purpose in mind, a new methodology to draw frequency mapping of dynamic light emission acquisition is reported. It is fully automated and based on wavelet transform and autocorrelation function. Regarding the possible use in an industrial context, the suggested method can help to localize abnormal emission activity and it gives some perspectives o…
A Non-Stationary MIMO Vehicle-to-Vehicle Channel Model Derived from the Geometrical Street Model
2011
In this paper, we derive a non-stationary multiple-input multiple-output (MIMO) vehicle-to-vehicle (V2V) channel model from the geometrical street model. Single-bounce scattering is assumed for both fixed and moving scatterers. The high mobility of the transmitter, the receiver, and the surrounding vehicles results in time-variant angles-of-departure (AODs) and angles-of-arrival (AOAs). This fact makes the model non-stationary. Starting from the geometrical model, an analytical expression is derived for the channel gain taking into account the impact of fixed and moving scatterers. The statistical properties of the proposed channel model are studied. Analytical solutions are provided for th…
Combination of modal responses consistent with seismic input representation
2004
The well-known modal superposition method for the evaluation of seismic response by the complete quadratic modal combination rule (CQC) is revisited. The most widely used version of the CQC rule utilizes correlation coefficients derived for white-noise excitation and neglects the influence of peak factor variation on the response. Here a simplified procedure for evaluation of correlation coefficients and peak factors consistent with the power spectral density of seismic excitation is proposed. The procedure is based on an approximate analytic expression for direct evaluation of the power spectral density of the excitation consistent with any prefixed response spectrum, and the evaluation of…
The design of measurement-based underwater acoustic channel simulators using the INLSA algorithm
2015
This paper utilizes the iterative nonlinear least square approximation (INLSA) algorithm for designing measurement-based wideband shallow underwater acoustic (UWA) channel simulators. Measurement-based channel simulators are essential for the test, optimization, and performance analysis of UWA communication systems. The aim is to fit the time-variant channel impulse response (TVCIR) of the simulation model to that of the measured UWA channel. The performance of the designed UWA channel simulator is assessed by comparing the time-frequency correlation function (TFCF), the power delay profile (PDP), and the probability density function (PDF) of the channel envelope with the corresponding quan…
Pattern recognition in cyclic and discrete skills performance from inertial measurement units
2014
The aim of this study is to compare and validate an Inertial Measurement Unit (IMU) relative to an optic system, and to propose methods for pattern recognition to capture behavioural dynamics during sport performance. IMU validation was conducted by comparing the motions of the two arms of a compass, which was equipped with IMUs and reflective landmarks detected by a multi-camera system. Spearman’s rank correlation tests showed good correlations between the IMU and multi-camera system, especially when the angles were normalized. Bland-Altman plot, root mean square and the normalized pairwise variability index showed low differences between the two systems, confirming the good accuracy level…
Hand-Held texting is less distracting than texting with the phone in a holder: anyway, don't do it
2015
We studied the effects of texting while driving and the effects of mobile phone position (hand-held, holder) on drivers' lane-keeping performance, experienced workload, and in-car glance durations in a motion-platform driving simulator with 24 participants. Overall, we found the known negative effects of texting on lane-keeping performance, workload, and visual attention on road, suggesting that texting on the road in any manner is not risk-free. As a novel finding, we found that hand-held texting led to fewer lane-keeping errors and shorter total glance times off road compared to texting with the phone in a holder. We suggest the explanation is that the drivers had considerably more experi…
Investigation on phospheonol pyruvate carboxylase and proline in damaged and indamaged needles of Picea Abies and Abies Alba
1998
The client of forest damage is rapidly characterized by visible criteria such as loss and yellowing of leaves and needles Additionally damage to Norway spruce (Picea abies) and silver fit (Abies alba) can be diagnosed by biochemical criteria. The results in the present study performed in 1993 and 1994 on six Norway Spruces of each of the eleven open air stands in south-western Germany indicate that the activity of phosphoenol pyruvate carboxylase (PEPC) correlates with the extent of damage and of the loss of needles, respectively. Needles of severely damaged trees had higher levels of PEPC than needles of healthy trees. There was also a positive correlation between the activity of PEPC and …
Geostatistical Microscale Study of Magnetic Susceptibility in Soil Profile and Magnetic Indicators of Potential Soil Pollution
2015
Directional variograms, along the soil profile, can be useful and precise tool that can be used to increase the precision of the assessment of soil pollution. The detail analysis of spatial variability in the soil profile can be also an important part of the standardization of soil magnetometry as a screening method for an assessment of soil pollution related to the dust deposition. The goal of this study was to investigate the correlation between basic parameters of spatial correlations of magnetic susceptibility in the soil profile, such as a range of correlation and a sill, and selected magnetometric indicators of soil pollution. Magnetic indicators were an area under the curve of magnet…
The distribution of phthalate esters in indoor dust of Palermo (Italy).
2013
In this work, phthalic acid esters (PAEs): dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate, benzyl butyl phthalate, bis(2-ethylhexyl) phthalate, and di-n-octyl phthalate in indoor dust (used as passive sampler) were investigated. The settled dust samples were collected from thirteen indoor environments from Palermo city. A fast and simple method using Soxhlet and GC–MS analysis has been optimized to identify and quantify the phthalates. Total phthalates concentrations in indoor dusts ranged from 269 to 4,831 mg/kg d.w. (d.w. = dry weight). The data show a linear correlation between total PAEs concentration and a single compound content, with the exclusion of the two …
Parent-Child Similarity in Environmental Attitudes: A Pairwise Comparison
2012
Are adolescents’ environmental attitudes similar to their parents’ attitudes? The main objective of this study is to examine what quantitative associations, if any, exist in parent-child environmental attitudes within the family. The survey data was collected assessing attitudes toward the environment and nature from 15-year-old students (n = 237) and their parents (n = 212) in Finland. A significant positive correlation emerged in environmental attitudes between mothers and fathers. Interestingly, the results revealed some indicative evidence that girls’ environmental attitudes could relate more to their father's than mother's attitudes. Girls were as positive in their environmental attitu…