Search results for "Video"
showing 10 items of 1348 documents
Wind gust estimation for precise quasi-hovering control of quadrotor aircraft
2021
Abstract This paper focuses on the control of quadrotor vehicles without wind sensors that are required to accurately track low-speed trajectories in the presence of moderate yet unknown wind gusts. By modeling the wind disturbance as exogenous inputs, and assuming that compensation of its effects can be achieved through quasi-static vehicle motions, this paper proposes an innovative estimation and control scheme comprising a linear dynamic filter for the estimation of such unknown inputs and requiring only position and attitude information. The filter is built upon results from Unknown Input Observer theory and allows estimation of wind and vehicle state without measurement of the wind its…
Two-Higgs leptonic minimal flavour violation
2011
We construct extensions of the Standard Model with two Higgs doublets, where there are flavour changing neutral currents both in the quark and leptonic sectors, with their strength fixed by the fermion mixing matrices $V_{CKM}$ and $V_{PMNS}$. These models are an extension to the leptonic sector of the class of models previously considered by Branco, Grimus and Lavoura, for the quark sector. We consider both the cases of Dirac and Majorana neutrinos and identify the minimal discrete symmetry required in order to implement the models in a natural way.
Multipole WIEN-filter for a high-resolution X-PEEM
1997
Abstract The development and construction of an X-PEEM with integral multipole WIEN-filter for spectromicroscopy with high lateral resolution is presented. All relevant electron-optical properties of the filter have been examined by field and trajectory calculations. Electric and magnetic multipole components (dipole, quadrupole and hexapole) can be chosen independently from each other, thus allowing electron-optical corrections. Theoretical values for the lateral resolution are in the range of 10 nm, experimental values of ≤25 nm have been achieved using the column without filter. The instrument is designed in particular for the use of Sychrotron radiation as well as new, high-brilliance l…
Generalization of Canny–Deriche filter for detection of noisy exponential edge
2002
This paper presents a generalization of the Canny-Deriche filter for ramp edge detection with optimization criteria used by Canny (signal-to-noise ratio, localization, and suppression of false responses). Using techniques similar to those developed by Deriche, we derive a filter which maximizes the product of the first two criteria under the constraint of the last one. The result is an infinite length impulse response filter which leads to a stable third-order recursive implementation. Its performance shows an increase of the signal-to-noise ratio in the case of blurred and noisy images, compared to the results obtained from Deriche's filter.
Low-Rank Tucker-2 Model for Multi-Subject fMRI Data Decomposition with Spatial Sparsity Constraint
2022
Tucker decomposition can provide an intuitive summary to understand brain function by decomposing multi-subject fMRI data into a core tensor and multiple factor matrices, and was mostly used to extract functional connectivity patterns across time/subjects using orthogonality constraints. However, these algorithms are unsuitable for extracting common spatial and temporal patterns across subjects due to distinct characteristics such as high-level noise. Motivated by a successful application of Tucker decomposition to image denoising and the intrinsic sparsity of spatial activations in fMRI, we propose a low-rank Tucker-2 model with spatial sparsity constraint to analyze multi-subject fMRI dat…
Corrispondenze
2018
Il video, ideato e realizzato per la mostra "Viaggio per Immagini. Palermo arabo-normanna e le Cattedrali di Cefalù e Monreale dal Grand Tour al riconoscimento UNESCO", è una elaborazione originale di fotografie di Rosellina Garbo, con la musica di Marco Betta. Un racconto multimediale che si dipana tra i monumenti dell'itinerario UNESCO e che ne mette in evidenza le relazioni geometriche, volumetriche e simboliche.
An Integrated Architecture for Surveillance and Monitoring in an Archaeological Site
2005
This paper describes an on-going work aimed at designing and deploying a system for the surveillance and monitoring of an archaeological site, namely the "Valley of the Temples" in Agrigento, Italy. Given the relevance of the site from an artistical and historical point of view, it is important to protect the monuments from malicious or simply incautious behavior; however, the vastity of the area to be monitored and the vague definition of its boundaries make it unpractical to provide extensive coverage through traditional sensors or similar devices. We describe the design of an architecture for the surveillance of the site and for the monitoring of the visitors' behavior consisting in an i…
Evaluating and developing teacher instructional practices in economics using a new video-based test
2022
Abstract Teachers’ instructional practices are important for student learning. However, there are few tools for evaluating instructional practices in social studies. To this end, we present a video-based instrument with teacher-student interactions for assessing teaching practices in a high school economics course. We investigate, using an iterative design-based methodology, the adaptation and validation of a test originally developed in Germany for use in the United States. We found that experienced economics teachers and those with more content knowledge demonstrated higher-level instructional skills, and were more flexibile with their thinking. Inexperienced economics teachers and those …
Efektīva video reklāma: TELE2 Latvija reklāmu sēriju analīze (2013-2015. gads)
2016
Bakalaura darbā “Efektīva video reklāma: Tele2 Latvija reklāmu sēriju analīze (2013-2015. gads)” tika pētītas 20 savstarpēji saistītas reklāmu epizodes un skatīta auditorijas attieksme pret “Tele2” reklāmu sērijām. Kā teorētiskais pamats tika skatīti efektīvas reklāmas parametri, video reklāmas veidošanās elementi un naratīva struktūra reklāmās. Darba empīriskajā daļā tiek analizētas epizodes, izmantojot kontentanalīzes kategorijas, lai izdalītu reklāmas elementus, kuri ietekmē reklāmas efektivitāti. Pēc efektivitātes parametriem un izdalītajiem elementiem kontentanalīzes kategorijās, tiek skatīta auditorijas attieksme pret reklāmu sērijām, izveidojot fokusgrupas interviju un aptauju. Darba…
Grasp-specific motor resonance is influenced by the visibility of the observed actor
2016
AbstractMotor resonance is the modulation of M1 corticospinal excitability induced by observation of others' actions. Recent brain imaging studies have revealed that viewing videos of grasping actions led to a differential activation of the ventral premotor cortex depending on whether the entire person is viewed versus only their disembodied hand. Here we used transcranial magnetic stimulation (TMS) to examine motor evoked potentials (MEPs) in the first dorsal interosseous (FDI) and abductor digiti minimi (ADM) during observation of videos or static images in which a whole person or merely the hand was seen reaching and grasping a peanut (precision grip) or an apple (whole hand grasp). Part…