Search results for " Computer"

Connectivity and Transformation in Work-Related Learning – Theoretical Foundations

2008

Radical innovation by theoretical abstraction - a challenge for the user-centred designer

2016

AbstractIt is generally accepted that scientific disciplines such as psychology, sociology, and anthropology contribute beneficially to design by providing understanding of users’ needs, experiences, and desires. Arguably, however, these disciplines have more to contribute, because they include theories and models that can be applied as design frames and principles. More specifically, goal-setting, visualization, thematization, and conceptual reconfiguration are general mechanisms through which theories translate into design contributions. Actualizing radical design solutions via these mechanisms is discussed: theories provide appropriate means of abstraction, which allows ‘distance’ from u…

Optical d-level frequency-time-based cluster states

2019

Cluster states, a specific class of multi-partite entangled states, are of particular importance for quantum science, as such systems are equivalent to the realization of one-way (or measurement-based) quantum computers [1]. In this scheme, algorithms are implemented through high-fidelity measurements on the parties of the state [2]. While two-level (i.e. qubit) cluster states have been realized so far, increasing the number of particles to boost the computational resource comes at the price of significantly reduced coherence time and detection rates, as well as increased sensitivity to noise, restricting the realization of discrete cluster states to a record of eight qubits. In contrast, t…

Discrete and Conservative Factorizations in Fib(B)

2021

AbstractWe focus on the transfer of some known orthogonal factorization systems from$$\mathsf {Cat}$$Catto the 2-category$${\mathsf {Fib}}(B)$$Fib(B)of fibrations over a fixed base categoryB: the internal version of thecomprehensive factorization, and the factorization systems given by (sequence of coidentifiers, discrete morphism) and (sequence of coinverters, conservative morphism) respectively. For the class of fibrewise opfibrations in$${\mathsf {Fib}}(B)$$Fib(B), the construction of the latter two simplify to a single coidentifier (respectively coinverter) followed by an internal discrete opfibration (resp. fibrewise opfibration in groupoids). We show how these results follow from thei…

Effect of inter-crystal scatter on estimation methods for random coincidences and subsequent correction.

2008

Random coincidences can contribute substantially to the background in positron emission tomography (PET). Several estimation methods are being used for correcting them. The goal of this study was to investigate the validity of techniques for random coincidence estimation, with various low-energy thresholds (LETs). Simulated singles list-mode data of the MADPET-II small animal PET scanner were used as input. The simulations have been performed using the GATE simulation toolkit. Several sources with different geometries have been employed. We evaluated the number of random events using three methods: delayed window (DW), singles rate (SR) and time histogram fitting (TH). Since the GATE simula…

Factors in the global assimilation of collaborative information technologies: an exploratory investigation in five regions

2008

The diffusion of innovation theory is deployed to investigate the global assimilation of collaborative information technologies (CITs). Based on the concepts of IT acquisition and utilization, an assimilation framework is presented to highlight four states (limited, focused, lagging, and pervasive) that capture the assimilation of conferencing and groupware CITs. Data collected from 538 organizations in the United States, Australia, Hong Kong, Norway, and Switzerland are aggregated and analyzed to explore assimilation patterns and the influence of decision-making pattern, functional integration, promotion of collaboration, organization size, and IT function size on the assimilation of CITs.…

Education Students’ Use of Collaborative Writing Tools in Collectively Reflective Essay Papers

2014

Published version of an article in the journal: Journal of Information Technology Education: Research. Also available from the publisher at: http://www.jite.org/documents/Vol13/JITEv13ResearchP091-120Brodahl0463.pdf Open Access Google Docs and EtherPad are Web 2.0 tools providing opportunity for multiple users to work online on the same document consecutively or simultaneously. Over the last few years a number of research papers on the use of these collaborative tools in a teaching and learning environment have been published. This work builds on that of Brodahl, Hadjerrouit, and Hansen (2011) expanding its case study. The theoretical framework is the same as the one underlying Brodahl et a…

3D Sensor-Based Obstacle Detection Comparing Octrees and Point clouds Using CUDA

2012

This paper presents adaptable methods for achieving fast collision detection using the GPU and Nvidia CUDA together with Octrees. Earlier related work have focused on serial methods, while this paper presents a parallel solution which shows that there is a great increase in time if the number of operations is large. Two different models of the environment and the industrial robot are presented, the first is Octrees at different resolutions, the second is a point cloud representation. The relative merits of the two different world model representations are shown. In particular, the experimental results show the potential of adapting the resolution of the robot and environment models to the t…

Improving color correction across camera and illumination changes by contextual sample selection

2012

International audience; In many tasks of machine vision applications, it is important that recorded colors remain constant, in the real world scene, even under changes of the illuminants and the cameras. Contrary to the human vision system, a machine vision system exhibits inadequate adaptability to the variation of lighting conditions. Automatic white bal- ance control available in commercial cameras is not sufficient to pro- vide reproducible color classification. We address this problem of color constancy on a large image database acquired with varying digi- tal cameras and lighting conditions. A device-independent color repre- sentation may be obtained by applying a chromatic adaptation…

A Gamut Preserving Color Image Quantization

2007

International audience; We propose a new approach for color image quantization which preserves the shape of the color gamut of the studied image. Quantization consists to find a set of color representative of the color distribution of the image. We are looking here for an optimal LUT (look up table) which contains information on the image's gamut and on the color distribution of this image. The main motivation of this work is to control the reproduction of color images on different output devices in order to have the same color feeling, coupling intrinsic informations on the image gamut and output device calibration. We have developped a color quantization algorithm based on an image depend…