Search results for "Cable"
showing 10 items of 329 documents
Power Line Communication in Medium Voltage Systems: Characterization of MV Cables
2008
The aim of this paper is to illustrate the development of a theoretical and experimental study on the characterization of medium voltage (MV) cables in the frequency range 25-200 kHz. Two transmission line configurations, line-ground and line-line, were considered in order to evaluate the main parameters, such as the characteristic impedance and the attenuation constant alpha. A simplified model of the line-ground configuration is proposed which allows one to evaluate the characteristic impedance and the attenuation constant by means of geometrical dimensions. The model was verified by experimental measurements on commonly used MV cables, RG7H1R, with an aluminium core of different sections…
Personal Social Networks of Community-Dwelling Oldest Old During the Covid-19 Pandemic—A Qualitative Study
2021
The COVID-19 pandemic and its related restrictions have affected the everyday life of older people. Advanced age is a significant predisposing factor for a more severe COVID-19 infection, increasing the risk for hospitalization and mortality. Even though restrictions have been, thus, well-grounded, they may also have had detrimental effects on the social well-being of older people. Personal networks and social activity are known protective factors against the premature decline in health and functioning, and it is widely acknowledged that social isolation increases feelings of loneliness, poor quality of life, and even the risk for diseases and disabilities among older adults. This qualitati…
Measurement of Physical Fitness and 24/7 Physical Activity, Standing, Sedentary Behavior, and Time in Bed in Working-Age Finns : Study Protocol for F…
2022
Background: Population studies gathering measured data on fitness and physical behavior, covering physical activity, standing, sedentary behavior, and time in bed, are scarce. This article describes the protocol of the FINFIT 2021 study that measures fitness and physical behavior in a population-based sample of adults and analyzes their associations and dose–response relationships with several health indicators. Methods: The study comprises a stratified random sample of 20–69-year-old men and women (n = 16,500) from seven city-centered regions in Finland. Physical behavior is measured 24/7 by tri-axial accelerometry and analyzed with validated MAD-APE algorithms. Health and fitness examinat…
Los Reglamentos comunitarios de coordinación: puntos críticos de la ley aplicable a la relación de afiliación
2021
El objeto de estudio de la presente tesis doctoral se centra en la determinación de la ley aplicable en materia de Seguridad Social, tercer pilar de la regulación de las relaciones laborales internacionales (junto con la competencia judicial internacional y la ley aplicable al contrato de trabajo). La determinación de esta ley, pese a ser un elemento clave en la toma de decisiones empresariales de índole laboral, constituye el área menos explorada por la doctrina científica. A causa de la elevada movilidad en el seno de la Unión y la posición privilegiada que el Derecho europeo ostenta para los países integrantes de la misma, destaca la regulación contenida en las normas comunitarias de coo…
RSV disease in infants and young children: Can we see a brighter future?
2022
Respiratory syncytial virus (RSV) is a highly contagious seasonal virus and the leading cause of Lower Respiratory Tract Infections (LRTI), including pneumonia and bronchiolitis in children. RSV-related LRTI cause approximately 3 million hospitalizations and 120,000 deaths annually among children <5 years of age. The majority of the burden of RSV occurs in previously healthy infants. Only a monoclonal antibody (mAb) has been approved against RSV infections in a restricted group, leaving an urgent unmet need for a large number of children potentially benefiting from preventive measures. Approaches under development include maternal vaccines to protect newborns, extended half-life monoclon…
Dinamisku tīmekļa risinājumu izstrāde Ruby on Rails ietvarā, izmantojot WebSocket tehnoloģiju
2020
Bakalaura darba ietvaros tika apskatīta WebSocket protokola implementācija, kas ir pamatā dinamiskās tīmekļa sistēmās Ruby on Rails ietvarā – ietvarā iebūvētais Action Cable, un kopienas veidotais AnyCable, kas ir Action Cable papildinājums. Bibliotēka AnyCable piedāvā iespēju kā WebSocket serveri izmantot kādu jau no implementētajiem variantiem vai izmantot citu ar AnyCable savietojamu WebSocket serveri, kas var būt arī paša veidots. Bakalaura darba rezultātā tika izstrādāta ar AnyCable savietojama WebSocket servera programmatūra Rust programmēšanas valodā, kas ir konkurētspējīga pašreiz pieejamajiem Ruby on Rails savietojamiem WebSocket tehnoloģijas risinājumiem, etalonuzdevumos uzrādot l…
Ley aplicable a los contratos de computación en nube
2022
El rápido cambio tecnológico, nos sitúa en una nueva era que da lugar a cambios transversales, fundado en datos que nutren Internet. En este sentido, se observa que la informática en la nube, es una de las plataformas que permiten apoyo a todas las nuevas tecnologías que van surgiendo. Su importancia va en aumento ante su creciente uso, a nivel nacional e internacional. Generalmente, la informática en la nube incluye un componente internacional debido a que los datos se almacenan o se transfieren entre servidores situados en diferentes países. Este elemento extranjero, puede plantear cuestiones sobre ley aplicable en caso de infracción, lo que nos lleva a plantear posibles soluciones al pro…
A Model for the Study of Sheath Currents in Medium Voltage Cables for Industrial Application
2020
In this paper, the implementation of a simulation model for studying the effect of cross-bonding of metallic sheaths and/or non-magnetic armor of single-core medium voltage cables in the same circuit is discussed. With the use of single-core cables, the resistive losses due to the induced circulating currents in cable sheaths or armors causes an increase of cable temperature that reduces its ampacity. In addition, the risk of electric shock due to induced voltages may be present if a person is exposed to the armor/sheath at the unbounded end. For this reason, special bonding techniques are used to significantly reduce these currents. The authors have implemented a model that could be used t…
The Industrial Applicability of PEA Space Charge Measurements, for Performance Optimization of HVDC Power Cables
2019
Cable manufacturing industries are constantly trying to improve the electrical performance of power cables. During the years, it was found that one of the most relevant degradation factors influencing the cable lifetime is the presence of space charge in the insulation layer. To detect the accumulated charge, the pulsed electro-acoustic (PEA) method is the most used technique. Despite the wide use of the PEA cell, several issues are still present. In particular, the PEA output signal is strongly disturbed by the acoustic waves reflections within the PEA cell. This causes the distortion of the output signal and therefore the misinterpretation of the charge profiles. This, in turn, may result…
Pre-sleep arousal and sleep quality during the COVID-19 lockdown in Italy
2021
Abstract Objective The COVID-19 pandemic has strongly affected daily habits and psychological wellbeing, and many studies point to large modifications in several sleep and sleep-related domains. Nevertheless, pre-sleep arousal during the pandemic has been substantially overlooked. Since hyperarousal represents one of the main factors for the development and the perpetuation of chronic insomnia disorder, the assessment of variables associated with high levels of pre-sleep arousal during the pandemic is clinically relevant. The study aimed to assess the prevalence and predictors of perceived sleep quality and pre-sleep arousal in an Italian sample during the COVID-19 lockdown. Methods We used…