Search results for " pattern"

showing 10 items of 2245 documents

Space-time FPCA Algorithm for clustering of multidimensional curves.

2016

In this paper we focus on finding clusters of multidimensional curves with spatio-temporal structure, applying a variant of a k-means algorithm based on the principal component rotation of data. The main advantage of this approach is to combine the clustering functional analysis of the multidimensional data, with smoothing methods based on generalized additive models, that cope with both the spatial and the temporal variability, and with functional principal components that takes into account the dependency between the curves.

FPCA clustering of multidimensional curves GAM spatio-temporal pattern
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Configurable low-cost plotter device for fabrication of multi-color sub-cellular scale microarrays.

2014

We report on the construction and operation of a low-cost plotter for fabrication of microarrays for multiplexed single-cell analyses. The printing head consists of polymeric pyramidal pens mounted on a rotation stage installed on an aluminium frame. This construction enables printing of microarrays onto glass substrates mounted on a tilt stage, controlled by a Lab-View operated user interface. The plotter can be assembled by typical academic workshops from components of less than 15 000 Euro. The functionality of the instrument is demonstrated by printing DNA microarrays on the area of 0.5 squared centimeters using up to three different oligonucleotides. Typical feature sizes are 5 μm diam…

FabricationMaterials scienceScale (ratio)NanotechnologyMultiplexingBiomaterialsUser-Computer InterfacePlotterHumansGeneral Materials ScienceBiochipOligonucleotide Array Sequence AnalysisEGF ReceptorsEpidermal Growth FactorOligonucleotideDNA-directed protein immobilization EGF receptors device automation multiplexed patterns polymer pen lithographyGeneral ChemistryMicrofluidic Analytical TechniquesErbB ReceptorsTissue Array AnalysisCosts and Cost AnalysisMCF-7 CellsPrintingDNA microarraySingle-Cell AnalysisBiotechnologySmall (Weinheim an der Bergstrasse, Germany)
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Multilevel pattern generation by GaN laser lithography: an application to beam shaper fabrication

2006

The new GaN lasers represent a unique combination of compactness, reliability, energy efficiency, and short wavelength. With respect to the previous state of the art in direct laser write lithography, based on gas lasers, this is resulting in a breakthrough, and is opening the way to real desktop micropatterning. The field of diffractive optics can immediately benefit by the availability of a new breed of pattern generators, based on such sources, mainly for fast turnaround device development. This paper presents the technical advantages involved in the use of 405 nm GaN lasers for one-step multilevel patterning. Beam modulation, exposure control and overall process strategy are discussed. …

FabricationMaterials sciencebusiness.industryLasersGallium nitrideLaserSettore ING-INF/01 - Elettronicalaw.inventionchemistry.chemical_compoundOpticschemistryDigital pattern generatorlawModulationlaser markingOptoelectronicsScanningbusinessLithographyBeam (structure)Maskless lithographySPIE Proceedings
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Nanostructured molecular surfaces: advances in investigation and patterning tools

2009

This feature article is aimed to showcase advanced soft and radiationless nanotools for the morphological characterization and for the preparation/modification of molecular surfaces, namely solid supported ultrathin films not exceeding 1–2 molecular layers. As to the characterization, the development of dynamic scanning force microscopy in attractive regime is presented as an important progress at least as far as it concerns imaging of nanoscale features of molecular surfaces with minimal probe–sample physical interaction. To date, this tool has been applied only by a few groups in spite of its larger resolution and image quality than the conventional scanning probe methods. As to the prepa…

FabricationNanostructurenanotechnologyChemistryResolution (electron density)surface patterningNanotechnologyGeneral ChemistryCharacterization (materials science)molecular surfaceMaterials ChemistrySelf-assemblyMolecular probeNanoscopic scaleLithographyJournal of Materials Chemistry
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Remote heart rate variability for emotional state monitoring

2018

International audience; Several researches have been conducted to recognize emotions using various modalities such as facial expressions , gestures, speech or physiological signals. Among all these modalities, physiological signals are especially interesting because they are mainly controlled by the autonomic nervous system. It has been shown for example that there is an undeniable relationship between emotional state and Heart Rate Variability (HRV). In this paper, we present a methodology to monitor emotional state from physiological signals acquired remotely. The method is based on a remote photoplethysmography (rPPG) algorithm that estimates remote Heart Rate Variability (rHRV) using a …

Facial expressionModalities[ INFO.INFO-TS ] Computer Science [cs]/Signal and Image Processing[INFO.INFO-TS] Computer Science [cs]/Signal and Image ProcessingComputer scienceSpeech recognition020208 electrical & electronic engineering0206 medical engineering[INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV]02 engineering and technology[ INFO.INFO-CV ] Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV]020601 biomedical engineeringSignal[INFO.INFO-CV] Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV][INFO.INFO-TS]Computer Science [cs]/Signal and Image ProcessingFeature (computer vision)Frequency domainPhotoplethysmogram0202 electrical engineering electronic engineering information engineeringHeart rate variabilityGesture
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How endogenous asymmetries in interregional market access trigger regional divergence

2005

International audience; We investigate how asymmetric trade patterns in differentiated products affect the regional distribution of economic activities. The asymmetry in interregional market access is an endogenous result of price competition and industry location and arises for intermediate values of trade costs. We show that the emergence of one-way trade in differentiated products gives rise to strong agglomeration forces and leads to the absorption of the smaller region's industry by the larger region. The number of spatial equilibria increases once the pattern of trade is endogenously accounted for.

Factor mobilityEconomic geographyMarket access[ SHS.ECO ] Humanities and Social Sciences/Economies and financesAsymmetric trade patterns[SHS.ECO] Humanities and Social Sciences/Economics and Finance[SHS.ECO]Humanities and Social Sciences/Economics and FinanceRegional divergence
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Combining feature extraction and expansion to improve classification based similarity learning

2017

Abstract Metric learning has been shown to outperform standard classification based similarity learning in a number of different contexts. In this paper, we show that the performance of classification similarity learning strongly depends on the data format used to learn the model. We then present an Enriched Classification Similarity Learning method that follows a hybrid approach that combines both feature extraction and feature expansion. In particular, we propose a data transformation and the use of a set of standard distances to supplement the information provided by the feature vectors of the training samples. The method is compared to state-of-the-art feature extraction and metric lear…

Feature extractionLinear classifier02 engineering and technologySemi-supervised learning010501 environmental sciencesMachine learningcomputer.software_genre01 natural sciencesk-nearest neighbors algorithmArtificial Intelligence0202 electrical engineering electronic engineering information engineering0105 earth and related environmental sciencesMathematicsbusiness.industryDimensionality reductionPattern recognitionStatistical classificationSignal Processing020201 artificial intelligence & image processingComputer Vision and Pattern RecognitionArtificial intelligencebusinessFeature learningcomputerSoftwareSimilarity learningPattern Recognition Letters
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Classification of spatio-temporal point pattern in the presence of clutter using K-th nearest neighbour distances

2019

In a point process spatio-temporal framework, we consider the problem of features detection in the presence of clutters. We extend the methodology of Byers and Raftery (1998) to the spatio-temporal context by considering the properties of the K-th nearest-neighbour distances. We make use of the spatio-temporal distance based on the Euclidean norm where the temporal term is properly weighted. We show the form of the probability distributions of such K-th nearest-neighbour distance. A mixture distribution, whose parameters are estimated with an EM algorithm, is used to classify points into clutters or features. We assess the performance of the proposed approach with a simulation study, togeth…

FeatureSpatio-temporal point patterns.EarthquakeClutterMixtureEM algorithmNearestneighbour distanceSettore SECS-S/01 - Statistica
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Large-scale Nanopatterning of Single Proteins used as Carriers of Magnetic Nanoparticles

2010

4 páginas, 4 figuras.

FerritinMaterials scienceScale (ratio)Soft lithographyNanolithographyMechanical EngineeringSupramolecular chemistryNanoparticleNanotechnologyProtein patterningSoft lithographyMagneticsProtein patterningNanolithographyMechanics of MaterialsFerritinsAnimalsNanoparticlesMagnetic nanoparticlesGeneral Materials ScienceHorsesAdvanced Materials
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Evaluation of Borderline Ovarian Tumor Recurrence Rate after Surgery with or without Fertility-Sparing Approach: Results of a Retrospective Analysis

2023

Borderline ovarian tumors (BOTs) comprise 15-20% of primary ovarian neoplasms and represent an independent disease entity among epithelial ovarian cancers. The present study (Clinical Trial ID: NCT05791838) aimed to report a retrospective analysis of the management and outcomes of 86 consecutive BOTs patients, 54 of which were at a reproductive age. All patients with BOTs undergoing surgical treatment from January 2010 to December 2017 were included. Data were retrospectively reviewed. High levels of Ca-125 were observed in 25.6% of the FIGO stage I patients and 58.3% of the advanced disease patients. Fertility-sparing surgery and comprehensive surgical staging were performed in 36.7% and 4…

Fertility-sparing surgeryBorderline ovarian tumorSurgical staging.Conservative surgeryMicropapillary patternSettore MED/40 - Ginecologia E Ostetricia
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