Search results for "Signal"
showing 10 items of 6924 documents
One-year implant survival following lateral window sinus augmentation using plasma rich in growth factors (PRGF) : a retrospective study
2019
Background The aim of this study was to assess one-year implant survival after lateral window sinus augmentation using PRGF combined with various bone grafting materials. Material and Methods This was a retrospective chart review and radiographic analysis of patients that had undergone lateral window sinus augmentation with PRGF and had dental implants placed at least 6 months post augmentation. All implants included were followed up for at least one year after placement. Demographic, sinus and implant related characteristics (residual ridge height, sinus membrane perforation, type of graft material, implant length and width and ISQ at placement) were analyzed. Results A total of 31 patient…
Wavelet analysis and neural network classifiers to detect mid-sagittal sections for nuchal translucency measurement
2016
We propose a methodology to support the physician in the automatic identification of mid-sagittal sections of the fetus in ultrasound videos acquired during the first trimester of pregnancy. A good mid-sagittal section is a key requirement to make the correct measurement of nuchal translucency which is one of the main marker for screening of chromosomal defects such as trisomy 13, 18 and 21. NT measurement is beyond the scope of this article. The proposed methodology is mainly based on wavelet analysis and neural network classifiers to detect the jawbone and on radial symmetry analysis to detect the choroid plexus. Those steps allow to identify the frames which represent correct mid-sagitta…
Generalization of Canny–Deriche filter for detection of noisy exponential edge
2002
This paper presents a generalization of the Canny-Deriche filter for ramp edge detection with optimization criteria used by Canny (signal-to-noise ratio, localization, and suppression of false responses). Using techniques similar to those developed by Deriche, we derive a filter which maximizes the product of the first two criteria under the constraint of the last one. The result is an infinite length impulse response filter which leads to a stable third-order recursive implementation. Its performance shows an increase of the signal-to-noise ratio in the case of blurred and noisy images, compared to the results obtained from Deriche's filter.
Towards adaptive localization in wireless sensor networks
2012
It is often useful or even indispensable to know the locations of the nodes in a wireless sensor network (WSN), from both network functionality and applications point of view. A potential yet one of the most challenging method is to utilize received signal strength indicator (RSSI) for distance estimation. Albeit easily adopted, using of RSSI is notorious for imprecise distance estimates which can lead to inaccuracies in location estimates. In this paper, we study RSSI-based localization in WSNs through simulation experiments. We evaluate and compare a hybrid algorithm and its modifications with well-known range-based and range-free localization algorithms. Simulation results indicate that …
UV light energy storage and thermoluminescence in AlN ceramics
2007
AlN ceramics, untreated and subjected to oxygen ion implantation, are studied for potential application in TL dosimetry of UV light. Based on photoluminescence and thermoluminescence measurements there are shown advantages of the selection of the 480 emission band for TL signal recording instead of the previously used 400 nm band: higher intensity of the TL signal, lower fading rate of the accumulated TL signal, excitation region (270-340 nm) corresponding to UV-B range, monitoring of which is actual in UV dosimetry. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
COST 241 intercomparison of nonlinear refractive index measurements in dispersion shifted optical fibres at =1550 nm
1997
COST 241 measurements of the nonlinear refractive index, n/sub 2/, exhibit a large scatter depending on the specific measurement technique. This is largely due to the electrostrictive contribution to the Kerr nonlinearity, as is revealed by the resonant behaviour of n/sub 2/ (with peak values up to 3.9 10/sup -20/ m/sup 2/ W/sup -1/) observed with signal modulation frequencies in the 0.11 GHz range.
Objectivization of the electrical discharge measurement results taken by the acoustic emission method
2006
The subject matter of this paper refers to the improvement of the acoustic emission method (AE) in its application for diagnostics of insulation systems of power appliances whereas the detailed subject matter is connected with determining the possibilities and indicating the range of using statistical and digital methods of signal processing for the evaluation of the AE pulses generated by partial discharges (PDs), which can occur in paper-oil insulation of power transformers.
Contextuality Analysis of the Double Slit Experiment (With a Glimpse Into Three Slits)
2018
The Contextuality-by-Default theory is illustrated on contextuality analysis of the idealized double-slit experiment. The experiment is described by a system of contextually labeled binary random variables each of which answers the question: has the particle hit the detector, having passed through a given slit (left or right) in a given state (open or closed)? This system of random variables is a cyclic system of rank 4, formally the same as the system describing the EPR/Bell paradigm with signaling. Unlike the latter, however, the system describing the double-slit experiment is always noncontextual, i.e., the context-dependence in it is entirely explainable in terms of direct influences of…
Generation of Hardware/Software systems based on CAL dataflow description
2011
International audience; This paper presents a new development of rapid prototyping tools for system design based on data-flow specifications. In this context, the efficiency of tools for the automatic translation from the data-flow programs to C and/or HDL are assessed by means of two design cases. The paper also introduces the new concept of the automatic synthesis of interfaces. Such generic interfaces are implemented by using an embedded microprocessor, which can support a large variety of interfaces already available as native IP libraries in the case of FPGA. The two design cases described here have been developed, tested and validated on different implementation platforms. The results…
Ras family genes: An interesting link between cell cycle and cancer
2002
Ras genes are evolutionary conserved and codify for a monomeric G protein binding GTP (active form) or GDP (inactive form). The ras genes are ubiquitously expressed although mRNA analysis suggests different level expression in tissue. Mutations in each ras gene frequently were found in different tumors, suggesting their involvement in the development of specific neoplasia. These mutations lead to a constitutive active and potentially oncogenic protein that could cause a deregulation of cell cycle. Ras protein moderates cellular responses at several mitogens and/or differentiation factors and at external stimuli. These stimuli activate a series of signal transduction pathways that either can…