Search results for "ndc"

A statistical model for magnitudes and angles of wavelet frame coefficients and its application to texture retrieval

2014

Abstract This paper presents a texture descriptor based on wavelet frame transforms. At each position in the image, and for each resolution level, we consider both vertical and horizontal wavelet detail coefficients as the components of a bivariate random vector. The magnitudes and angles of these vectors are computed. At each level the empirical histogram of magnitudes is modeled by a Generalized Gamma distribution, and the empirical histogram of angles is modeled by a different version of the von Mises distribution that accounts for histograms with 2 modes. Each texture is characterized by few parameters. A new distance is presented (based on the Kullback–Leibler divergence) that allows g…

A combined single range and single image device for low-cost measurement of building facade features

2008

The dimensions of building facades and window apertures are usually determined by making direct measurements using tapes and plummets. This approach, however, has a number of drawbacks including the physical risk to which the persons making the measurements are exposed. This paper proposes an indirect approach based on close range photogrammetry that is inexpensive, simple, fast and safe, and which does not require specialist staff or direct ground control measurements. The method is based on taking a picture using a digital camera and measuring the distance to the object using a handheld laser distance meter. Both items of equipment are mounted on a specially designed support that allows t…

Combined Endo- and Exoscopic Semi-robotic Manipulator System for Image Guided Operations

2006

This paper describes the development of a robotic assistance system for image guided operations. To minimize operation time, a multimodal user interface enables freehand robotic manipulation of an extracorporeal stereoscopic digital camera (exoscope) and an endoscope. The surgeon thereby wears a head-mounted unit with a binocular display, a head tracker, a microphone and earphones. Different view positioning and adjustment modes can be selected by voice and controlled by head rotation while pressing a miniature confirmation button with a finger. Initial studies focused on the evaluation and optimization of the intuitiveness, comfort and precision of different modes of operation, including a…

Scalable Electro-Optic Control of Localized Bistable Switching in Broad-Area VCSELs Using Reconfigurable Funnel Waveguides

2017

We demonstrate a steplike optical modulation based on the activation and deactivation of a bistable localized structure using a photoinduced and reconfigurable miniaturized 30 × 30 μm electroactivated funnel waveguide. Control of a single 10-μm-diameter spot in a 200-μm-diameter vertical-cavity surfaceemitting laser at 980 nm is achieved modulating the phase of an exciting beam in the specific position of the spot in the cavity. This localized on-off response can be scaled into arrays and offer a possible route to fast integrated optical logical functions and memory at low intensities at near-infrared wavelengths.

Ambient Art : Creative Information Representation

2007

Ambient art is the aesthetic presentation of information, using artistic techniques to achieve a pleasing image that also contains hidden depths, where exposure to it over time allows a viewer to understand something about the information sources that it represents. This paper reviews the artistic and computational background of ambient systems, and presents two case studies of systems developed by our research team, from their initial design to the experiences of the people encountering them. The first case presents a photo mosaic of images based on the news headlines coupled with a structured picture based on the weather; the second presents stylistic perspectives on activity in a public …

1989

By endcapping of living polystyrene with ethylene oxide and subsequent reaction with bromoacetyl bromide a polymer with a bromoacetoxy endgroup was obtained. This was used as a macroinitiator for the living cationic polymerization of 1-azabicyclo[4.2.0]octane. The structure and composition of the so formed two-block copolymer was elucidated by different methods. The ratio of the two block and their lengths were varied within broad limits.

Optical remote sensor for alcohol concentration in blood

2012

In this paper we incorporate recently developed novel optical approach for extraction of remote vibration sources to estimate the alcohol concentration in blood stream.

Design of a customized pattern for improving color constancy across camera and illumination changes

2010

International audience; This paper adresses the problem of color constancy on a large image database acquired with varying digital cameras and lighting conditions. Automatic white balance control proposed by an available commercial camera is not sufficient to provide reproducible color classification. A device-independent color representation may be obtained by applying a chromatic adaptation transform, from a calibrated color checker pattern included in the field of view. Instead of using the standard Macbeth color checker, we suggest to select judicious colors to design a customized pattern from contextual information. A comparative study demonstrates that this approach insures a stronger…

A dynamic adjustment model of saccade lengths in reading for word-spaced orthographies : evidence from simulations and invisible boundary experiments

2021

Contemporary models of eye movement control in reading assume a discrete target word selection process preceding saccade length computation, while the selection itself is assumed to be driven by word identification processes. However, a potentially more parsimonious, dynamic adjustment view allows both next word length and its content (e.g. orthographic) to modulate saccade length in a continuous manner. Based on a recently proposed center-based saccade length account (a new regression model of forward saccade length is introduced and validated in a simulation study. Further, additional simulations and gaze-contingent invisible boundary experiments were used to study the cognitive mechanism…

Efectos de los campos eléctrico y magnético sobre los estados electrónicos excitados en nanoestructuras cuánticas semiconductoras

2013

Las nanoestructuras cuánticas semiconductoras ofrecen un gran potencial en cuanto al diseño de nuevos materiales con propiedades ópticas novedosas. El confinamiento cuántico y la aplicación de campos eléctrico y magnético externos muestran una riqueza de efectos cuánticos cuya aplicación es en muchos casos desconocida. Es notable al respecto la gran cantidad de comprtamientos no lineales que muestran, por ejemplo, la energía excitónica, los tiempos de recombinación, el efecto túnel y la consiguiente extinción de la señal espectral de fotoluminiscencia en los semiconductores. Lo notable de los modelos, y que queda confirmado por los experimentos es la competición entre tres efectos presentes…