72 research outputs found
Edge flow
In this paper we introduce a new data driven method to novelty detection and object definition in dynamic video streams that indiscriminately detects both static and moving objects in the scene. A sliding window density estimation is introduced in order to reliably detect texture edges. A Sobel filtering process is used to extract gradient of edges. Using this new approach, the detection of object textures1 can be done accurately and in real-time. In this paper we demonstrate the capabilities of the algorithm on video scenarios, and show that object textures in the scene are reliably detected. We are able to show clearly the capability of the algorithm to be robust in occlusion scenarios; working in real-time, and defining clear objects where other techniques attribute such small detections to noise
Reactivity of polynuclear zinc-thiolate sites
International audienceThe proton affinities of a series of mono- and polynuclear zinc-thiolate compounds, mimicking zing finger protein and metallothioneins sites, have been investigated by Density Functional Theory calculations. This allows to evaluate the intrinsic nucleophilicity of synthetic and natural zinc-bound thiolates and to compare their relative reactivities. The site specificity of the experimental thiolate alkylation for the Zn4Cys11 clusters in metallothioneins is well reproduced, as well as the relative reactivities of ZnHis2Cys2, ZnHisCys3 and ZnCys4 zinc finger sites. Our results also show that terminal thiolates, bound to only one Lewis acid, are more reactive than bridging thiolates. Synthetic inorganic clusters and the Zn4Cys9His2 cluster found in a cyanobacterial metallothionein are less reactive than Zn4Cys11 and Zn3Cys9 clusters in metallothioneins. These results allow discussing the influence of the protein backbone and residues on the reactivity of these natural clusters
Language and Technology in Wales: Volume II
This ebook is based on some of the main papers presented during the Welsh Language Technologies Academic Symposium 2022 and 2023. It contains chapters dealing with the latest technology in the field of Artificial Intelligence (AI), natural language processing (NLP) and speech technology, techniques that continue to offer much to less-resourced languages. In addition to reporting on the latest technology available for the Welsh language, included are discussions on language technology tools for languages that are in a similar situation, namely Breton, Cornish and Irish
The Application of 199 Hg NMR and 199m Hg Perturbed Angular Correlation (PAC) Spectroscopy to Define the Biological Chemistry of Hg II : A Case Study with Designed Two- and Three-Stranded Coiled Coils
The use of de novo designed peptides is a powerful strategy to elucidate Hg II –protein interactions and to gain insight into the chemistry of Hg II in biological systems. Cysteine derivatives of the designed Α-helical peptides of the TRI family [Ac-G-(L a K b A c L d E e E f K g ) 4 -G-NH 2 ] bind Hg II at high pH values and at peptide/Hg II ratios of 3:1 with an unusual trigonal thiolate coordination mode. The resulting Hg II complexes are good water-soluble models for Hg II binding to the protein MerR. We have carried out a parallel study using 199 Hg NMR and 199m Hg perturbed angular correlation (PAC) spectroscopy to characterize the distinct species that are generated under different pH conditions and peptide TRI 14L9C/Hg II ratios. These studies prove for the first time the formation of [Hg{(TRI 14L9C) 2 -(TRI 14L9C[bond]H)}], a dithiolate–Hg II complex in the hydrophobic interior of the three-stranded coiled coil (TRI 14L9C) 3 . 199 Hg NMR and 199m Hg PAC data demonstrate that this dithiolate–Hg II complex is different from the dithiolate [Hg(TRI 14L9C) 2 ], and that the presence of third Α-helix, containing a protonated cysteine, breaks the symmetry of the coordination environment present in the complex [Hg(TRI 14L9C) 2 ]. As the pH is raised, the deprotonation of this third cysteine generates the trigonal thiolate–Hg II complex Hg(TRI 14L9C) 3 − on a timescale that is slower than the NMR timescale (0.01–10 14ms). The formation of the species [Hg{(TRI 14L9C) 2 (TRI 14L9C[bond]H)}] is the result of a compromise between the high affinity of Hg II to form dithiolate complexes and the preference of the peptide to form a three-stranded coiled coil.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/57382/1/9178_ftp.pd
Iaith a Thechnoleg yng Nghymru: Cyfrol II
Mae’r gyfrol hon yn seiliedig ar rai o’r prif bapurau a draddodwyd yn ystod Symposiwm Academaidd Technolegau Iaith Cymru 2022 a 2023. Ceir ynddi benodau sy’n ymdrin â’r dechnoleg ddiweddara ym maes Deallusrwydd Artiffisial (AI), prosesu iaith naturiol (NLP) a thechnoleg lleferydd, technegau sydd yn parhau i gynnig llawer i ieithoedd llai eu hadnoddau. Yn ogystal ag adrodd ar y dechnoleg ddiweddara sydd ar gael i’r Gymraeg, ceir trafodaethau ar offer technoleg iaith ieithoedd eraill sydd mewn sefyllfa debyg megis y Llydaweg, y Gernyweg, a’r Wyddeleg
Real-time novelty detection in video using background subtraction techniques:state of the art a practical review
Autonomously detecting novelties using background subtraction has quickly become a very important area of image analysis with many different approaches to novelty detection and the output therein. The ultimate goal of the approaches is to be robust to false detections and noise whilst using as little computational power as possible. This review focuses on some of the most prominent pixel-wise background subtraction techniques currently in use, and compares and contrasts their attributes and capabilities. The purpose of this review is to practically summarize the pixel-wise approaches and suggest a way forward from these techniques
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