Search results for "vision."

Corresponding-pair procedure: a new approach to simulation of dichromatic color perception.

2004

The dichromatic color appearance of a chromatic stimulus T can be described if a stimulus S is found that verifies that a normal observer experiences the same sensation viewing S as a dichromat viewing T. If dichromatic and normal versions of the same color vision model are available, S can be computed by applying the inverse of the normal model to the descriptors of T obtained with the dichromatic model. We give analytical form to this algorithm, which we call the corresponding-pair procedure. The analytical form highlights the requisites that a color vision model must verify for this procedure to be used. To show the capabilities of the method, we apply the algorithm to different color vi…

Lit environments quality: A software for the analysis of luminance maps obtained with the HDR imaging technique

2013

Abstract Energy performance of lighting systems has assumed a significant role in the assessment of buildings’ consumptions and consequently lighting design is aimed to reduce installed power but at the same time to achieve an excellent lighting quality both for visual and health purposes. Lighting design is nowadays essentially based on illuminance values on visual tasks and surrounding areas, but today designers’ and researchers’ interest is focused on the analysis of luminance maps obtained through video luminance meters or with numeric simulation tools. Luminance maps availability focus the attention on a more accurate study of the light reaching the eyes (luminance), rather than on the…

Brightness and contrast do not affect visually induced motion sickness in a passively-flown fixed-base flight simulator

2016

Abstract Background Visually Induced Motion Sickness (VIMS) or simulator sickness is often elicited by a visual stimulus that lacks the appropriate vestibular or proprioceptive feedback. In this study, we chose to investigate the effects of brightness and contrast of the visual scene on VIMS. Hypothesis We hypothesized that visual environments differing in brightness or contrast would differentially induce VIMS. The symptoms of VIMS should be most severe for the combination of high brightness and high contrast and conversely lowest for the low brightness and low contrast condition. Methods 33 healthy subjects were tested in a fixed-base flight simulator. Each subject flew in four consecutiv…

Personalized multimedia touristic services for hybrid broadcast/broadband mobile receivers

2010

This paper presents the topology of a multimedia tourism service that targets mobile devices equipped with broadband and either multicast or broadcast access capabilities. Multicast / Broadcast access is used to handle the delivery of multimedia data to many simultaneous users in the service area. The solution adopted is based on existing standards for mobile TV services, but introducing features that enable the provision of generic multimedia services on top of mobile hybrid broadband and broadcast networks. Furthermore, this paper shows how to use standardized interfaces originally defined for interactive mobile TV broadcasting to build personalized mobile multimedia services that do not …

Trends in Prevalence of Blindness and Distance and Near Vision Impairment Over 30 Years and Contribution to the Global Burden of Disease in 2020

2020

Background: The Vision Loss Expert Group and Global Burden of Disease Study have extensively updated estimates of global vision loss burden in 2020, temporal changeover 3 decades and forecasts for 2050. Methods: A systematic review and meta-analysis was conducted of population-based datasets relevant to vision impairment (VI) from January 1980 to October 2018. Hierarchical models were fitted to estimate 2020 prevalence (with 95% uncertainty intervals, UI) of (1) mild VI (presenting visual acuity [PVA] 6/12). Findings: In 2020, an estimated 43.2 million (95% UI: 37.5-48.2 million; 55% female) people were blind, 295.3 (95% UI 267.0-325.5) million had MSVI, 257.3 (95% UI 232.2-284.7) million h…

A Geometric Algorithm for Ray/Bézier Surfaces Intersection Using Quasi-Interpolating Control Net

2008

In this paper, we present a new geometric algorithm to compute the intersection between a ray and a rectangular Bezier patch. The novelty of our approach resides in the use of bounds of the difference between a Bezier patch and its quasi-interpolating control net. The quasi-interpolating polygon of a Bezier surface of arbitrary degree approximates the limit surface within a precision that is function of the second order difference of the control points, which allows for very simple projections and 2D intersection tests to determine sub-patches containing a potential intersection. Our algorithm is simple, because it only determines a 2D parametric interval containing the solution, and effici…

Cover Feature: Palladium‐Catalyzed Electrophilic C–H‐Bond Fluorination: Mechanistic Overview and Supporting Evidence (Eur. J. Org. Chem. 2‐3/2019)

2018

A Fuzzy Logic C-Means Clustering Algorithm to Enhance Microcalcifications Clusters in Digital Mammograms

2011

The detection of microcalcifications is a hard task, since they are quite small and often poorly contrasted against the background of images. The Computer Aided Detection (CAD) systems could be very useful for breast cancer control. In this paper, we report a method to enhance microcalcifications cluster in digital mammograms. A Fuzzy Logic clustering algorithm with a set of features is used for clustering microcalcifications. The method described was tested on simulated clusters of microcalcifications, so that the location of the cluster within the breast and the exact number of microcalcifications is known.

Index-based triangulation method for efficient generation of large three-dimensional ultrasonic C-scans

2018

The demand for high-speed ultrasonic scanning of large and complex components is driven by a desire to reduce production bottlenecks during the non-destructive evaluation (NDE) of critical parts. Emerging systems (including robotic inspection) allow for the collection of large volumes of data in short time spans, compared to existing inspection systems. To maximise throughput, it is crucial that the reconstructed inspection datasets are generated and evaluated rapidly without loss of detail. This requires new data visualisation and analysis tools capable of mapping complex geometries while guaranteeing full coverage. This paper presents an entirely new approach for the visualisation of thre…

Get a Mac : conversations in Apple's advertising campaign

2015

Mainontaa on nykyaikana lähes kaikkialla. Yksi yleisimmistä mainonnan muodoista on televisiomainokset, joita useat näkevät päivittäin. Tästä esimerkkinä on Applen televisiokampanja, jota esitettiin vuosina 2006–2009. Sitä on tutkittu useasta eri näkökulmasta, mutta mainoksissa olevan keskustelun tutkiminen on jäänyt vähemmälle. Myös kampanjassa käytetyn keskustelun yhteyttä suostutteluun, joka on kaiken mainonnan tavoite, on tutkittu vain vähän. Tämän tutkielman tavoitteena oli tutkia mainosten keskusteluja keskustelunanalyysin avulla ja selvittää, miten ne suostuttelivat ihmisiä ostamaan Mac-tietokoneen. Kampanjassa oli kaiken kaikkiaan 66 mainosta, joista tähän tutkielmaan valittiin 12. N…