Search results for "Artifact"
showing 10 items of 193 documents
ERP denoising in multichannel EEG data using contrasts between signal and noise subspaces
2009
Abstract In this paper, a new method intended for ERP denoising in multichannel EEG data is discussed. The denoising is done by separating ERP/noise subspaces in multidimensional EEG data by a linear transformation and the following dimension reduction by ignoring noise components during inverse transformation. The separation matrix is found based on the assumption that ERP sources are deterministic for all repetitions of the same type of stimulus within the experiment, while the other noise sources do not obey the determinancy property. A detailed derivation of the technique is given together with the analysis of the results of its application to a real high-density EEG data set. The inter…
Worm-like artifacts in exfoliative cytology.
2006
The presence of worms in cytological smears is occasionally reported, although various other structures exist that may be confused with such parasites. We present eight worm-like artifacts observed in routine Papanicolaou smears. Recognition of these structures is important to avoid overvaluation or confusion with true worms. Diagn. Cytopathol. 2006;34:636–639. © 2006 Wiley–Liss, Inc.
Maximum likelihood difference scaling of image quality in compression-degraded images.
2007
International audience; Lossy image compression techniques allow arbitrarily high compression rates but at the price of poor image quality. We applied maximum likelihood difference scaling to evaluate image quality of nine images, each compressed via vector quantization to ten different levels, within two different color spaces, RGB and CIE 1976 L(*)a(*)b(*). In L(*)a(*)b(*) space, images could be compressed on average by 32% more than in RGB space, with little additional loss in quality. Further compression led to marked perceptual changes. Our approach permits a rapid, direct measurement of the consequences of image compression for human observers.
Performance Measurement of Mobile Manipulators
2015
International audience; This paper describes a concept for measuring the reproducible performance of mobile manipulators to be used for assembly or other similar tasks. An automatic guided vehicle with an onboard robot arm was programmed to repeatedly move to and stop at a novel, reconfigurable mobile manipulator artifact (RMMA), sense the RMMA, and detect targets on the RMMA. The manipulator moved a laser retroreflective sensor to detect small reflectors that can be reconfigured to measure various manipulator positions and orientations (poses). This paper describes calibration of a multi-camera,motion capture system using a 6 degree-of-freedom metrology bar and then using the camera system…
Le cimetière du second Âge du fer de la Tournière à Lailly (Yonne) : nouvelle analyse des fouilles anciennes
2021
International audience; Cette étude présente de manière critique les découvertes qui ont été faites à la fin du xix e siècle et au début du xx e siècle à Lailly La Tournerie (Yonne). Elle propose un classement typologique et chronologique de tous les objets mis au jour par catégorie fonctionnelle, ainsi que la reconstitution, pour la première fois, de plusieurs ensembles clos. Elle a ainsi permis de proposer une évolution de ce cimetière entre le second quart du v e siècle (La Tène A ancienne) et la première décennie du ii e siècle avant J.-C. (La Tène C1). L'analyse des pratiques funéraires a également été abordée à l'aide d'un dépouillement systématique des rares données existantes. Leur …
PICTURES, GESTURES AND DISCOURSES: A CASE STUDY WITH KINDERGARTEN STUDENTS DISCOVERING LEGO BRICKS
The awareness of the importance to look, through a mathematical lens, to the children drawings, gestures and discourses, considering them as diagnostic tools for the mathematics competences, stays at the base of this contribution. It discusses a didactic experience conducted in a Kindergarten (students 5 or 6 years old) in which we asked children to represent and discus a Lego block with a drawing and speech, observed from different prospective. The discussed results seem to us interesting both for researchers in Mathematics Education and for Kindergarten teachers who want to deepen the role of drawing and gestures as an expressive and diagnostic forms to analyze students’ knowledge, abilit…
NEW APPLICATIONS IN THE USE OF CELLULOSE PULP FOR THE INTEGRATION OF WOODEN SUPPORTS
2017
Cellulose pulp, mainly utilized as a support for cleaning stone material, in this study, is proposed as a filler for wooden supports. In the last 10 years, pulp has been used in many restoration works carried out in the laboratory of the Diocesan Museum (MDP) in Palermo, including both wooden sculptures and panel paintings. These artworks, exhibited in the MDP, are constantly monitored in order to evaluate the effectiveness of cellulose pulp as a filler, assessing its durability and bio-receptivity. In particular, structural characteristics, drying time, shrinkage, loss in weight, affinity to the pigments, etc., were simultaneously evaluated. Tests were also carried out on artificially aged…
Re-exposure in cone beam CT of the dentomaxillofacial region: a retrospective study.
2018
Cone beam CT (CBCT) often uses a smaller field of view compared to conventional CT scans. This might lead to a wrong field of view with the need for secondary exposure (“retakes”). The purpose of this retrospective study was to assess the frequency of re-exposures in CBCT and to identify whether the parameters age, gender, and field of view have an influence on the re-exposure of the patient. Additionally, the causes of re-exposures were determined and categorized. METHODS: In a retrospective cohort study CBCT images of 4986 patients from the patient database from the Department of Oral Radiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany were included a…
Kvalitātes nosacījumi kontrastmammogrāfijā pie krūts vēža izmeklējumiem
2022
Autora izvēlētā bakalaura darba tēma - “Kvalitātes nosacījumi kontrastmamogrāfijā pie krūts vēža izmeklējumiem”. Bakalaura darbs sastāv no ievada daļas, teorētiskās daļas, pētnieciskās daļas, secinājumiem un ieteikumiem. Bakalaura darbā apskatīta un analizēta literatūra par krūts dziedzera anatomiju un fizioloģiju, krūts dziedzeru onkopatoloģijām, kontrastmamogrāfijas izmeklējumiem, izmeklējumu artefaktiem un protokolu vadlīnijām. Darba autore izvirzīja darba mērķi: noskaidrot kontrastmamogrāfijas nozīmi krūts vēža diagnostikā. Kā pētniecības metode tika izmantota - kvalitatīvā kontentanalīze.
Sketcching sonic interactions
2019
This chapter provides an overview of methods and practices for sketching sound in interactive contexts. The chapter stresses the role and importance of producing and interacting with provisional sound representations in conceptual sound design. The cognitive benefits of embodied sound sketching are discussed and outlined by means of practical examples and basic exercises. In particular, vocalizations and gestures are proposed as primary cognitive artifacts available to sound designers to enact sonic impressions and displays, cooperatively.