Search results for "REDUCTION"
showing 10 items of 2058 documents
Scene-based noise reduction on a smart camera
2012
International audience; Raw output data from CMOS image sensors tends to exhibit significant noise called Fixed-Pattern Noise (FPN) due to on-die variations between pixel photodetectors. FPN is often corrected by subtracting its value, estimated through calibration, from the sensor's raw signal. This paper introduces an on-line scene-based technique for an improved FPN compensation which does not rely on calibration, and hence is more robust to the dynamic changes in the FPN which may occur slowly over time. Development has been done with a special emphasis on real-time hardware implementation on a FPGA-based smart camera. Experimental results on different scenes are depicted showing that t…
Noise removal using a nonlinear two-dimensional diffusion network
1998
Un reseau electrique non lineaire bidimensionnel, constitue de N×N cellules identiques, et modelisant l’equation de Nagumo discrete est presente. A l’aide d’une nouvelle description de la fonction non lineaire, on peut predire analytiquement l’evolution temporelle de la partie coherente du signal, ainsi que celle des perturbations de petites amplitudes qui lui sont superposees. Enfin, des applications a l’amelioration du rapport signal sur bruit, ou au traitement d’images sont suggerees.
Modelling biogeochemical processes in sediments from the north-western Adriatic Sea: response to enhanced particulate organic carbon fluxes
2018
This work presents the result of a study carried out in the north-western Adriatic Sea, by combining two different types of biogeochemical models with field sampling efforts. A longline mussel farm was taken as a local source of perturbation to the natural particulate organic carbon (POC) downward flux. This flux was first quantified by means of a pelagic model of POC deposition coupled to sediment trap data, and its effects on sediment bioirrigation capacity and organic matter (OM) degradation pathways were investigated constraining an early diagenesis model by using original data collected in sediment porewater. The measurements were performed at stations located inside and outside the ar…
Uncertainty-reducing cooperation scripts in online learning environments
2004
Online learning courses can create new interaction situations for participants who have not previously worked with each other. Initially, there is some degree of uncertainty between participants in these interaction situations. According to the uncertainty reduction theory, low uncertainty increases theamount of discourse and decreases information seeking. Thus, uncertainty may influence online discourseand learning. However, the relation of uncertainty reduction to learning outcomes has not yet been investigated systematically. Cooperation scripts may reduce uncertainty, and therefore enhance learning.A cooperation script, which aims to reduce uncertainty at a cognitive level, was chosen f…
Effets simultanés de niveaux croissants de glucose et de pressions partielles en oxygène sur la dénitrification et la réduction dissimilative du nitr…
1998
International audience; Dissimilatory nitrate reduction to ammonium (DNRA) and its importance in comparison to denitrification were studied in soil samples artificially repacked to control water potential and porosity, and incubated for 72 h. Labelled nitrate (100 mg N.kg-’ dry soil, 21.8 % 15N in excess) and increasing levels of glucose-C (250, 500 and 1 000 mg glucose-Ckg-’ dry soil) were initially added to the soil samples to obtain increasing glucose-C/nitrate-N ratios of 2.5,5 and 10, which were then subjected to different 0, partial pressures (0,0.5, 1.0 and 2.0 % (v/v)). The results confirmed the good reproducibility of the experimental condi- tions using this method. Denitrification…
Differential Responses of Nitrate Reducer Community Size, Structure, and Activity to Tillage Systems
2009
ABSTRACT The main objective of this study was to determine how the size, structure, and activity of the nitrate reducer community were affected by adoption of a conservative tillage system as an alternative to conventional tillage. The experimental field, established in Madagascar in 1991, consists of plots subjected to conventional tillage or direct-seeding mulch-based cropping systems (DM), both amended with three different fertilization regimes. Comparisons of size, structure, and activity of the nitrate reducer community in samples collected from the top layer in 2005 and 2006 revealed that all characteristics of this functional community were affected by the tillage system, with increa…
Simulateur de pulvérisation localisée d’herbicide
2019
Site-specific spraying is a technological lever to reduce the herbicide amount used in the case of chemical control of weeds. At the present time, detection and control technologies are available to apply herbicide only where weeds are present and thus provide an alternative to homogeneous application of chemicals on the entire surface of the field. In order to assess this practice, a digital simulator has been developed combining virtual infestation maps with different theoretical sprayer configurations. Simulations were used to localize herbicide applications and quantify herbicide reduction based on the spatial distribution of weeds and the width of independent spray units (boom sections…
Contribution of the Temporal Dominance of Sensations (TDS) method to the sensory description of subtle differences in partially dealcoholized red win…
2007
ln this study, effect of partial alcohol reductio.n on the sensory modification of red wines was investigated. Preliminary triangle tests indicated the existencèof very slight differences between the dealcoholized wines of the study. Therefore, adapted descriptive methodologies had ta be used. ln addition to a comparative sensory profile, the Temporal Dominance of Sensations (TDS) method was chosen. Both types of profiles will be linked ta consumer preferences. A Merlat and a Syrah wine were partially dealcoholized using reverse osmosis technique to span a range of four different alcohol contents (14 % to 10 %) by grape variety. ln a first step, the four wines of each variety were compared …
Sensory science: new needs and challenges
2018
Using cross-modal interactions to counterbalance salt reduction in solid foods
2011
International audience; We investigated odour-induced saltiness enhancement (OISE) in a solid model cheese with the aim of evaluating the influence of cross-modal interactions (odour-texture-taste) on saltiness perception and assessing the efficacy of using OISE to counterbalance salt reduction. Four model cheeses, varying in texture, were flavoured with three commercial tasteless aromas (comte cheese, sardine and carrot) differently associated with salty and cheesy food products. Twenty-seven consumers evaluated taste intensity, aroma intensity and its congruence with the product flavour, and the overall pleasantness of 12 flavoured and four unflavoured samples. The comparison of the perce…