Search results for "observer"
showing 10 items of 345 documents
Localization from inertial data and sporadic position measurements
2020
International audience; A novel estimation strategy for inertial navigation in indoor/outdoor environments is proposed with a specific attention to the sporadic nature of the non-periodic measurements. After introducing the inertial navigation model, we introduce an observer providing an asymptotic estimate of the plant state. We use a hybrid dynamical systems representation for our results, in order to provide an effective, and elegant theoretical framework. The estimation error dynamics with the proposed observer shows a peculiar cascaded interconnection of three subsystems (allowing for intuitive gain tuning), with perturbations occurring either on the jump or on the flow dynamics (depen…
Observateur et contrôle optimal : améliorer l'efficacité de la conduite automobile avec Kalman et Pontryagin
2010
The PhD presents a combined approach to improving individual car efficiency. An optimal observer, the Extended Kalman Filter, is used to create an efficiency model for the car. Particular attention was paid to handling the asynchronous and redundant nature of the measurement data. A low-cost sensor suite developed to measure data is described. This sensor suite was installed on multiple vehicles to good success. It employsan accelerometer, gps, fuel injector timer, and Vss input to measure all the data necessary to reconstruct the car's state. This observer and sensor suite can be used as the base for any study which requires car efficiency maps, allowing research to proceed without manufac…
2020
Visually induced motion sickness is an unpleasant but common side-effect of many simulations and VR-applications. We investigated whether an earth-fixed reference frame provided in the simulation is able to reduce motion sickness. To do so, we created a moving starfield that did not contain any indicators of the spatial orientation of the observer. The observer wore a head-mounted display (HTC Vive) and was simulated to move through the randomly oscillating starfield, a time-to-contact task had to be carried out. Two colored stars on collision course with each other had to be spotted, then they disappeared and the time of their collision had to be judged. Eye-movements, task performance, an…
Saliency Based Aesthetic Cut of Digital Images
2013
Aesthetic cut of photos is a process well known to professional photographers. It consists of cutting the original photo to remove less relevant parts close to the borders leaving in this way the interesting subjects in a position that is perceived by the observer as more pleasant. In this paper we propose a saliency based technique to automatically perform aesthetic cut in images. We use a standard method to estimate the saliency map and propose some post processing on the map to make it more suitable for our scope. We then apply a greedy algorithm to determine the cut (i.e. the most important part of the original image) both in the cases of free and fixed aspect ratio. Experimental result…
Electromagnetic spectrum and color vision
2004
In most of occasions the maps, drawings and printed images are elaborated thinking that the observer will visualize them with illuminants like the light of the day. With these illuminants, for example the CIE D/sub 65/, we can distinguish the great quantity of colors that it is capable the human eye. But if the illuminant has a very different spectrum than the light of day, for example the light of acetylene, the number of colors that we are able to distinguish can decrease drastically.
Robust fault detection for switched systems with time-varying delay using delta operator approach
2014
Nationwide interobserver variation in the diagnosis of follicular lymphoma. A study of the pathologists of GISL (Gruppo Italiano Studi Linfomi).
2010
Inter- and Intraobserver Variation in the Assessment of Preoperative Colostograms in Male Anorectal Malformations: An ARM-Net Consortium Survey
2020
Aim:Male patients with anorectal malformations (ARM) are classified according to presence and level of the recto-urinary fistula. This is traditionally established by a preoperative high-pressure distal colostogram that may be variably interpreted by different surgeons. The aim of this study was to evaluate the inter- and intraobserver variation in the assessment by pediatric surgeons of preoperative colostograms with respect to the level of the recto-urinary fistula. Materials and Methods:Sixteen pediatric surgeons from 14 European centers belonging to the ARM-Net Consortium twice scored 130 images of distal colostograms taken in sagittal projection at a median age of 66 days of life (rang…
Positive L1 observer design for positive Switched systems
2014
Published version of an article in the journal: Circuits, Systems, and Signal Processing. Also available from the publisher at: http://dx.doi.org/10.1007/s00034-013-9737-6 This paper investigates the problem of L1 observer design for positive switched systems. Firstly, a new kind of positive L1 observer is proposed for positive switched linear delay-free systems with observable and unobservable subsystems. Based on the average dwell time approach, a sufficient condition is proposed to ensure the existence of the positive L1 observer. Under the condition obtained, the estimated error converges to zero exponentially, and the L1 -gain from the disturbance input to the estimated error is less t…
The effects of image compression on quantitative measurements of digital panoramic radiographs
2012
WOS: 000314401800026