Search results for "spatio-temporal"

Temporal incoherent solitons supported by a defocusing nonlinearity with anomalous dispersion

2012

http://pra.aps.org/; International audience; We study temporal incoherent solitons in noninstantaneous response nonlinear media. Contrarily to the usual temporal soliton, which is known to require a focusing nonlinearity with anomalous dispersion, we show that a highly noninstantaneous nonlinear response leads to incoherent soliton structures which require the inverted situation: In the focusing regime (and anomalous dispersion) the incoherent wave packet experiences an unlimited spreading, whereas in the defocusing regime (still with anomalous dispersion) the incoherent wave packet exhibits a self-trapping. These counterintuitive results are explained in detail by a long-range Vlasov formu…

Noise Disturbances and Calls for Police Service in València (Spain): A Logistic Model with Spatial and Temporal Effects

2019

The purpose of this paper is to explore the presence of spatial and temporal effects on the calls for noise disturbance service reported to the Local Police of Val&egrave

Local Spatio-Temporal Log-Gaussian Cox Processes for seismic data analysis

2022

We propose a local version of the spatio-temporal log-Gaussian Cox processes (LGCPs) employing the Local Indicators of Spatio-Temporal Association (LISTA) functions into the minimum contrast procedure to obtain space as well as time-varying parameters. We resort to the joint minimum contrast method fitting method to estimate the set of second-order parameters for the class of Spatio-Temporal LGCPs. We employ the proposed methodology to analyse real seismic data occurred Greece between 2004 and 2015.

Large-scale long-term passive-acoustic monitoring reveals spatio-temporal activity patterns of boreal bats

2023

The distribution ranges and spatio-temporal patterns in the occurrence and activity of boreal bats are yet largely unknown due to their cryptic lifestyle and lack of suitable and efficient study methods. We approached the issue by establishing a permanent passive-acoustic sampling setup spanning the area of Finland to gain an understanding on how latitude affects bat species composition and activity patterns in northern Europe. The recorded bat calls were semi-automatically identified for three target taxa; Myotis spp., Eptesicus nilssonii or Pipistrellus nathusii and the seasonal activity patterns were modeled for each taxa across the seven sampling years (2015–2021). We found an increase …

Detection of spatio-temporal local structure on seismic data

2017

For the description of the seismicity of an area, the comparison between local features of background and induced events could be a new perspective of research. In spatio-temporal point process, local second-order statistics provide information on the relationships of each event and its nearby events. In this paper, we use a test based on local indicators of spatio-temporal association (LISTA functions) for identifying different local structures comparing the two previous sets of events. We present a simulation study on the test and show the main results of the application on Greece earthquake data.

Discrete spectral incoherent solitons in nonlinear media with noninstantaneous response

2011

International audience; We show theoretically that nonlinear optical media characterized by a finite response time may support the existence of discrete spectral incoherent solitons. The structure of the soliton consists of three incoherent spectral bands that propagate in frequency space toward the low-frequency components in a discrete fashion and with a constant velocity. Discrete spectral incoherent solitons do not exhibit a confinement in the space-time domain, but exclusively in the frequency domain. The kinetic theory describes in detail all the essential properties of discrete spectral incoherent solitons: A quantitative agreement has been obtained between simulations of the kinetic…

Using Semantic Web Technologies to Follow the Evolution of Entities in Time and Space

2013

International audience; In this paper we present the "continuum model". Our work follows a "perdurantism" approach and is designed to handle dynamic phenomena extending the 4D-fluent with the use of semantic web technologies. In our approach we represent dynamic entities as constituted by timeslices each with semantic, geometric, temporal and identity components. Our model is able to link the diverse representations of an entity and allows the inference of qualitative information from quantitative one. The inference results are later added to the ontology in order to improve knowledge about the phenomenon. The model has been implemented using OWL and SWRL. Our preliminary results are promis…

Temporal and spatial variation of the algal community in a southern Mediterranean shallow system

2010

The algal community of a shallow system located in Western Sicily (Mediterranean Sea) has been investigated over 1 year in eight ponds (fredde). The spatio-temporal variation in total algal coverage, species richness and coverage in relation to environmental variables has been analysed. The algal community was very species-poor. A total of 50 taxa, mainly detached algae, were identified. A dominance of filamentous and foliose taxa was observed. Significant spatio-temporal differences in total algal coverage, species richness and coverage between the ponds of group A and those of group B were found. The separation into groups A and B was made a priori on the basis of different levels of prox…

Les Fleurs bleues de Raymond Queneau : le roman hybride

2015

β-Amyrin Synthase1 Controls the Accumulation of the Major Saponins Present in Pea (Pisum sativum)

2021

Abstract The use of pulses as ingredients for the production of food products rich in plant proteins is increasing. However, protein fractions prepared from pea or other pulses contain significant amounts of saponins, glycosylated triterpenes that can impart an undesirable bitter taste when used as an ingredient in foodstuffs. In this article, we describe the identification and characterization of a gene involved in saponin biosynthesis during pea seed development, by screening mutants obtained from two Pisum sativum TILLING (Targeting Induced Local Lesions IN Genomes) populations in two different genetic backgrounds. The mutations studied are located in a gene designated PsBAS1 (β-amyrin s…