Search results for "cept"

Colour and luminance contrasts predict the human detection of natural stimuli in complex visual environments.

2017

Much of what we know about human colour perception has come from psychophysical studies conducted in tightly-controlled laboratory settings. An enduring challenge, however, lies in extrapolating this knowledge to the noisy conditions that characterize our actual visual experience. Here we combine statistical models of visual perception with empirical data to explore how chromatic (hue/saturation) and achromatic (luminant) information underpins the detection and classification of stimuli in a complex forest environment. The data best support a simple linear model of stimulus detection as an additive function of both luminance and saturation contrast. The strength of each predictor is modest …

Four steps to identify mechanisms of ICT4D: A critical realism-based methodology

2018

Teachers’ intention to use educational video games: The moderating role of gender and age

2018

Educational video games represent an educational change that challenges teachers and managers of Higher Education institutions in several ways including their attitude formation and behavioural intention. Using a Technology Acceptance Model (TAM) approach a research model is developed to predict teachers’ behavioural intention to use educational video games in their courses. The research model is tested via structural equation modelling (SEM) on a sample of 312 Higher Education teachers. Main results suggest that perceived usefulness influences in a direct and positive way teachers’ behavioural intention while perceived ease of use indirectly influences intention through perceived usefulnes…

Usability and acceptability assessment of an empathic virtual agent to prevent major depression

2016

In Human-Computer Interaction, the adaptation of the content and the way of how this content is communicated to the users in interactive sessions is a critical issue to promote the acceptability and usability of any computational system. We present a user-adapted interactive platform to identify and provide an early intervention for symptoms of depression and suicide. In particular, we describe the work performed to assess users' system acceptability and usability. An empathic Virtual Agent is the main interface with the user, and it has been designed to generate the appropriate dialogues and emotions during the interactions according to the detected user's specific needs. This personalizat…

Barriers and facilitators of older people's mHealth usage: a qualitative review of older people's views

2018

The aim of this qualitative evidence synthesis is to identify and assess existing\ud evidence on barriers to and facilitators of older people’s usage of mHealth. Existing\ud literature identified many factors that affect people’s experiences and perceptions of\ud mHealth, which are in turn influenced by their personal circumstances and biography.\ud The following themes were identified using the thematic synthesis approach: (a)\ud perception of usefulness, (b) user requirements, (c) self-efficacy, (d) sense of self and\ud control, (e) privacy and confidentiality, and (f) cost. MHealth devices and services are\ud complex interventions that have to be integrated into an older person’s life in…

User experiences of a mobile mental well-being intervention among pregnant women

2016

Postnatal depression affects 10 to 15 percent of women after childbirth. Acceptance and commitment therapy (ACT) is associated with better mental well-being and lower levels of depression. Digital ACT solutions enable providing potentially cost-effective access to interventions. This paper reports the user experiences of an ACT-based mobile mental well-being intervention among pregnant women. Twenty-nine mothers were recruited to a 6-month study. Usage rates were collected via usage logs and user experiences via questionnaires and interviews. The total usage time of the application was about 53 min per user. The application was perceived easy to use. The most common barriers of use were: co…

Evaluation of Perception Latencies in a Human-Robot Collaborative Environment

2020

The latency in vision-based sensor systems used in human-robot collaborative environments is an important safety parameter which in most cases has been neglected by researchers. The main reason for this neglect is the lack of an accurate ground-truth sensor system with a minimal delay to benchmark the vision-sensors against. In this paper the latencies of 3D vision-based sensors are experimentally evaluated and analyzed using an accurate laser-tracker system which communicates on a dedicated EtherCAT channel with minimal delay. The experimental results in the paper demonstrate that the latency in the vision-based sensor system is many orders higher than the latency in the control and actuat…

Human Systems Design: Towards an Integrative Conceptual Framework

2020

International audience; Conceiving artefacts and tools is one of the major key characteristics of the human species. Since the beginning of automation and even more since the spreading of computer science, this activity has become more and more challenging especially through the analysis of the different interaction modes between the artifacts and the human. Nowadays, developing an artifact that must interact with a human is requiring an integrative point of view which must include biological, physical and cybernetical concerns. The current norms aimed at characterizing the quality and the relevance of human machine interface are generally limited to standard interfaces and/or to specific d…

Conceptual Key Competency Model for Smart Factories in Production Processes

2020

Abstract Background and Purpose: The aim of the study is to develop a conceptual key competency model for smart factories in production processes, focused on the automotive industry, as innovation and continuous development in this industry are at the forefront and represent the key to its long-term success. Methodology: For the purpose of the research, we used a semi-structured interview as a method of data collection. Participants were segmented into three homogeneous groups, which are industry experts, university professors and secondary education teachers, and government experts. In order to analyse the qualitative data, we used the method of content analysis. Results: Based on the anal…

Adjusted bat algorithm for tuning of support vector machine parameters

2016

Support vector machines are powerful and often used technique of supervised learning applied to classification. Quality of the constructed classifier can be improved by appropriate selection of the learning parameters. These parameters are often tuned using grid search with relatively large step. This optimization process can be done computationally more efficiently and more precisely using stochastic search metaheuristics. In this paper we propose adjusted bat algorithm for support vector machines parameter optimization and show that compared to the grid search it leads to a better classifier. We tested our approach on standard set of benchmark data sets from UCI machine learning repositor…