Search results for "spread"

Wavefront Recovery: Shack-Hartmann Aberrometry vs PhaseLift Using a Single Binary Amplitude Modulating Mask

2019

We investigate whether a wavefront can be recovered by using a single mask rotated in four different positions. Results show that PhaseLift can recover the wavefront from intensity measurements using such a kind of modulation.

Combining hectometric and decametric satellite observations to provide near real time decametric FAPAR product

2017

Abstract A wide range of ecological, agricultural, hydrological and meteorological applications at local to regional scales requires decametric biophysical data. However, before the launch of SENTINEL-2A, only few decametric products are produced and most of them remain limited by the small number of available observations, mostly due to a moderate revisit frequency combined with cloud occurrence. Conversely, kilometric and hectometric biophysical products are now widely available with almost complete and continuous coverage, but the associated spatial resolution limits the application over heterogeneous landscapes. The objective of this study is to combine unfrequent decametric spatial res…

Evaluation of the performance of multifocal intraocular lenses image quality: analysis of the standard methods

2007

Purpose: To analyze the standard methods used to describe intraocular lenses (IOL) and to suggest some improvements to make them applicable for multifocal IOLs. Methods: The EN-ISO standards and the standards of the American National Standards Institute (ANSI) for the evaluation of the performance of IOLs are tested for multifocal IOLs. The MTF of the one refractive multifocal IOL and two hybrid refractive-diffractive multifocal IOLs is measured for both distance focus and near focus and using different pupil sizes. Results: The average modulation (AM) from 0 to 100 c/mm of multifocal IOLs (for the distance focus) is about 40-50% lower than the AM of monofocal IOLs, for all pupil sizes stud…

2021

Abstract We propose a signal deconvolution procedure for imaging spectrometer data, where a measured point spread function (PSF) is deconvolved itself before being used for deconvolution of the signal. We evaluate the effectiveness of our procedure for improvement of the spatio-spectral signal, as well as our target application, i.e. estimation of sun-induced fluorescence (SIF). Imaging spectrometers are well established instruments for remote sensing. When used for scientific purposes these instruments are usually calibrated on a regular basis. In our case the point spread function of the optics is measured in an elaborate procedure with a tunable monochromator point light source. PSFs are…

Czy Nysius huttoni (Hemiptera: Heteroptera: Lygaeidae), gatunek obcy dla Europy, może mieć w Polsce sprzyjające warunki do bytowania?

2020

Nysius huttoni, the species endemic to New Zealand, is regarded as a pest which feeding can seriously reduce crop establishment in forage brassicas. It was discovered for the first time in Europe in 2002 (the Netherlands) and has spread in several European countries (Belgium, France, United Kingdom, Germany). Although detailed data on the natural spread of N. huttoni is lacking, it can theoretically be transported over long distances with infested plants, and is often found on apple and kiwi fruit packages exported from New Zealand. The species was hitherto not reported from Poland, therefore its potential geographic distribution was modelled using maximum entropy (Max-Ent) in order to pred…

Characterization of Radio Frequency Echo using frequency sweeping and power analysis

2014

International audience; Coupling between repeater's antennas, called Radio Frequency Echo (RFE) deteriorates signal quality and compromises system stability. If the channel insulation is insufficient, the power in the closed-loop raises with time according to the gain margin value. Multiple methods of echo cancellation exists. Generally, these techniques are based on correlation calculation and adaptive filtering. However, their efficiency and algorithm's convergence speed are calling into question under signal's modulation and real-time constraints, specially with narrow band signals having frequency hopping as GSM or TETRA. This paper describes a real time method of RFE detection and esti…

Intermittent Low-Dose IFN Gamma Treatment for Metastatic Renal Cell Carcinoma: Analysis of Factors Predicting Clinical Response and Long-Term Survival

1995

Background: Objective tumor remissions are induced by a variety of immunomodulating agents in a minority of patients suffering from metastasizing renal cell carcinoma. The results of different clinical studies, however, varied greatly for each of these treatment modalities. In order to elucidate potential causes for this variability and to further study the long-term results of intermittent low-dose IFN gamma therapy in patients with advanced renal cell cancer (RCC) we retrospectively analyzed factors predicting clinical response and long-term survival of 121 patients. Material and Methods: We retrospectively analyzed the clinical results of 5 phase II studies treating 121 patients with int…

Influence of ocular aberrations on the diameter of retinal blood vessels

2011

Lower-order and higher-order ocular aberrations influence not only visual perception but also appearance of retinal images. We suggest that the diameter of blood vessels may differ for various patterns of aberrations based on how the maps of point spread functions are orientated to these vessels. We tested our hypothesis by a star chart simulation method and by using simulating aberrations in a real image of a living retina. We observed that broadening of the blood vessels due to ocular aberrations depends not only on the relative orientation of the wavefront but also on their actual width. The change in the diameter ratio is clinically significant and is comparable to changes in the arteri…

Seismogenic rotational slumps and translational glides in pelagic deep-water carbonates. Upper Tithonian-Berriasian of Southern Tethyan margin (W Sic…

2017

Abstract Soft-sediment deformation structures (SSDSs), which reflect sediment mobilization processes, are helpful to identify punctual events of paleoenvironmental stresses. In the upper Tithonian-Berriasian calpionellid pelagic limestone of the Lattimusa Fm. outcropping in the Barracu section (W Sicily), paleoenvironmental restoration reveals the occurrence of a deep-water flat basin, characterised by undeformed planar bedding, laterally passing to a gentle slope where the deformed horizons alternate with undeformed beds. Here, two types of gravity slides have been differentiated on the basis of different kinds of SSDSs, brittle deformation, involved lithofacies, geometry and morphology. T…

Relationships between oral characteristics, bolus formation and aroma compound releases during the consumption of fat spread in humans

2011

Source : 13th Weurman Flavour Research Symposium - Zaragoza, Spain - September 27th – 30th, 201; International audience; The release and perception of flavour compounds is an important factor for the acceptance of a food product. It is a complex echanism that depends not only on the food’s chemical composition and structure, but also on in-mouth mechanisms involved in its breakdown. To date, most of the studies have been focused on hard or semi-hard product such as cheese for instance (1, 2). Among the works published on dairy product, fat spreads were not considered while they represent an important market. However these products are particularly interesting by their structure and composit…