Search results for "working"
showing 10 items of 2747 documents
Deflation-Based FastICA With Adaptive Choices of Nonlinearities
2014
Deflation-based FastICA is a popular method for independent component analysis. In the standard deflation-base d approach the row vectors of the unmixing matrix are extracted one after another always using the same nonlinearities. In prac- tice the user has to choose the nonlinearities and the efficiency and robustness of the estimation procedure then strongly depends on this choice as well as on the order in which the components are extracted. In this paper we propose a novel adaptive two- stage deflation-based FastICA algorithm that (i) allows one to use different nonlinearities for different components and (ii) optimizes the order in which the components are extracted. Based on a consist…
OLS Identification of network topologies
2011
Abstract In many applications, it is important to derive information about the topology and the internal connections of more dynamical systems interacting together. Examples can be found in fields as diverse as Economics, Neuroscience and Biochemistry. The paper deals with the problem of deriving a descriptive model of a network, collecting the node outputs as time series with no use of a priori insight on the topology. We cast the problem as the optimization of a cost function where a set of parameters are used to operate a trade-off between accuracy and complexity in the final model. The problem of reducing the complexity is addressed by fixing a certain degree of sparsity and finding the…
Accelerating Application Migration in HPC
2016
It is predicted that the number of cores per node will rapidly increase with the upcoming era of exascale supercomputers. As a result, multiple applications will have to share one node and compete for the (often scarce) resources available on this node. Furthermore, the growing number of hardware components causes a decrease in the mean time between failures. Application migration between nodes has been proposed as a tool to mitigate these two problems: Bottlenecks due to resource sharing can be addressed by load balancing schemes which migrate applications; and hardware errors can often be tolerated by the system if faulty nodes are detected and processes are migrated ahead of time.
Field Measurements and Parameter Calibrations of Propagation Model for Digital Audio Broadcasting in Norway
2018
During 2017, digital audio broadcasting (DAB) replaces frequency modulation (FM) broadcasting and becomes the only technology for national terrestrial audio broadcasting services in Norway. As Norway is the first country that replaces FM completely with DAB, it is of great importance to measure the signal strength of such a technology in massive deployments and to tune a simulation model as a reference for future studies. Therefore, field measurements of received signal strength are carried out in a typical Norwegian area in this work. Based on the data obtained from the measurements, a simulator with a recent empirical propagation model, namely, ITU-R P.1546-5, has been calibrated. The fin…
Projected fringes for the measurement of large aluminum ingots
2010
The method of projected fringes is applied to the measurement of the surface topography of aluminum ingots with surface areas of several square meters. The measurements are performed inside the casting hall of an aluminum factory. To meet the challenges encountered in such a demanding environment, it is important to keep the equipment as simple and robust as possible. Therefore a method for locating the fringe positions with sub-pixel accuracy without using for example phase shifting techniques is applied. Also the nonlinearity of the phase when using divergent illumination is discussed. The developed measuring system is tested measuring eight different aluminum ingots, and the results agre…
The Safety of Slaughterhouse Workers during the Pandemic Crisis
2021
The working conditions in a slaughterhouse are difficult because of the low temperatures, high humidity, and little natural light. Therefore, in these facilities, there is a high demand in the maintenance of strict hygiene rules. Lately, the new SARS-CoV-2 pandemic situation has brought new challenges in the meat industry, as this sector has to maintain its operability to supply the meat and meat products demanded by the consumers. In this challenging period, the safety of the workers is as important as keeping the high demands for the safety of the meat and meat products along with consumer confidence. This paper aims to give an overview of the risks associated with the SARS-CoV-2 virus tr…
An Efficient Wiener Path Integral Technique Formulation for Stochastic Response Determination of Nonlinear MDOF Systems
2015
The recently developed approximate Wiener path integral (WPI) technique for determining the stochastic response of nonlinear/hysteretic multi-degree-of-freedom (MDOF) systems has proven to be reliable and significantly more efficient than a Monte Carlo simulation (MCS) treatment of the problem for low-dimensional systems. Nevertheless, the standard implementation of the WPI technique can be computationally cumbersome for relatively high-dimensional MDOF systems. In this paper, a novel WPI technique formulation/implementation is developed by combining the “localization” capabilities of the WPI solution framework with an appropriately chosen expansion for approximating the system response PDF…
The Impact of Internet and Social Media Use on Well-Being
2021
The present research examines the longitudinal average impact of frequency of use of Internet and social networking sites (SNS) on subjective well-being of adolescents in Germany. Based on five-wave panel data that cover a period of nine years, we disentangle between-person and within-person effects of media use on depressive symptomatology and life satisfaction as indicators of subjective well-being. Additionally, we control for confounders such as TV use, self-esteem, and satisfaction with friends. We found that frequency of Internet use in general and use of SNS in particular is not substantially related subjective well-being. The explanatory power of general Internet use or SNS use to p…
A two-layer security model for accessing multimedia content in social networks
2016
La seguridad de un sitio web es hoy en día una de las principales preocupaciones de los administradores de sistemas. La seguridad es también el reto más importante al que se enfrentan los desarrolladores web a la hora de diseñar una plataforma fiable que ofrezca servicios a los usuarios públicos. Es bien sabido que el contenido multimedia en la web está en continuo crecimiento y, recientemente, este tipo de medios se utiliza cada vez más en las redes sociales. El acceso a los contenidos multimedia en el contexto de las redes sociales debe ser fácil y seguro. En este artículo se presenta un modelo de seguridad con capacidad semántica para el acceso a contenidos multimedia en las redes social…
Default Mode Network Efficiency Is Correlated With Deficits in Inhibition in Adolescents With Inhalant Use Disorder
2020
It is well established that alterations in cognitive function and damage to brain structures are often found in adolescents who have substance use disorder (SUD). However, deficits in executive cognitive functioning in adolescents related to the vulnerability and consumption of such substances are not well known. In this study, we use graph theoretic analysis to compare the network efficiency in the resting state for three networks---default mode network (DMN), salience network (SN) and fronto-parietal network (FPN)---between inhalant-consuming adolescents and a control group (12 to 17 years old). We analysed whether the efficiency of these functional networks was related to working memory,…