Search results for "level"
showing 10 items of 3465 documents
Work-related and personal predictors of COVID-19 transmission: evidence from the UK and USA
2021
ObjectiveTo develop evidence of work-related and personal predictors of COVID-19 transmission.Setting and respondentsData are drawn from a population survey of individuals in the USA and UK conducted in June 2020.Background methodsRegression models are estimated for 1467 individuals in which reported evidence of infection depends on work-related factors as well as a variety of personal controls.ResultsThe following themes emerge from the analysis. First, a range of work-related factors are significant sources of variation in COVID-19 infection as indicated by self-reports of medical diagnosis or symptoms. This includes evidence about workplace types, consultation about safety and union memb…
Alteraciones del sueño producidas por el ruido ambiental*
1989
ResumenEste articulo presenta los resultados de una encuesta realizada con el objetivo de valorar distintos aspectos relacionados con el ruido ambiental y sus efectos sobre determinadas comunidades urbanas. Un total de 263 residentes en 5 emplazamientos diferentes de la ciudad de Valencia fueron entrevistados. En estos 5 emplazamientos se realizaron de manera independiente una serie de medidas de los niveles de ruido durante las 24 horas del dia y en distintos días de la semana.:El 400%0 de los encuestados manifestó tener alguna dificultad para dormirse y el 59% de ellos lo atribuyó al ruido causado por el tráfico. Asimismo, un 49% de los encuestados declaró despertarse durante la noche (el…
The effects of muscle mass and muscle quality on cardio-metabolic risk in peripubertal girls: a longitudinal study from childhood to early adulthood.
2017
Increased cardio-metabolic risk is well documented in children and adolescents with obesity and normal weight obesity (NWO). However, the associations of muscle mass and muscle quality with cardio-metabolic risk, independent of weight status from childhood to adulthood, has not been examined. A total of 236 girls were followed from pre-puberty to early adulthood. Fat mass (FM) and lean mass (LM) of the whole body were assessed by a dual-energy X-ray absorptiometry; muscle cross-sectional area (mCSA), muscle density (mDen; skeletal muscle fat content) of the lower leg by the peripheral quantitative computerized tomography; and blood glucose, insulin, triglycerides and high-density lipoprotei…
Comparison of three adhesive systems in class II composite restorations in endodontically treated teeth : influence of Er:YAG laser conditioning and …
2018
Background Dental surface conditioning by Er:YAG laser is currently being investigated, as not all of the mechanisms and effects of this technique have been clearly studied. Thus, the aim of the present study was to assess the cervical microleakage of Class II resin composite restorations in endodontically treated teeth following either the respective conventional conditioning or additional Er:YAG laser conditioning, in association with varied adhesives. Material and methods Standardized mesial-occlusal-distal cavities (two gingival walls positioned in dentin and enamel, respectively) were created in 60 extracted human premolar teeth. Following the completion of the endodontic therapy, the …
Entrepreneurial self-identity, perceived corruption, exogenous and endogenous obstacles as antecedents of entrepreneurial intention in Italy
2019
Although entrepreneurship is considered one of the most powerful drivers of national economies around the world, there is little consensus about what informal factors foster entrepreneurial intention. In accordance with recent literature, entrepreneurial self-identity perception, the perception of corruption in the entrepreneurship ecosystem, and perceived exogenous and endogenous obstacles to entrepreneurship were hypothesized as antecedents of college students&rsquo
Postgraduate level analog microelectronics course based on cadence IC software and AMS 0.35 µm technology
2021
An analog microelectronics design course at the post-graduate level is described in this paper. In 30 h, students with different engineering background receive a basic but solid formation by implementing a complete microelectronics design flow, following current industry standards. The course deals with fundamental design blocks as well as specific computer aided design tools. This course can be taught, as it is, as a fundamental module in general electronics/communications masters, but it can be also tuned to match specific curriculum constraints, if required. It has been successfully taught for two years, with minor adjustments, within the Telecommunications Engineering Master, at the Un…
PERFORMANCE ASSESSMENT IN SCIENCE NATIONAL LEVEL DIAGNOSTIC TESTS
2018
National Centre of Education of the Republic of Latvia in 2016 lunched national project of the renewal of the curriculum for education funded by the European Social Fund. One of the key priorities of successful implementation of the new education curriculum is transforming national level assessment system.Assessment system measuring student performance must meet different requirements from the traditional measurement instrument assessing content knowledge.Analysing 2017 national level science assessment diagnostic tests of 15-16 years old students, it is impossible to discriminate student different level of performance. Student, demonstrating singly stored pieces of knowledge, integrating p…
Simulation of a single-phase five-level cascaded H-Bridge inverter with multicarrier SPWM B-Spline based modulation techniques
2017
Multilevel Power Inverters are now often used to convert DC to AC voltage waveform. This kind of converter allows high power quality with low output harmonics and lower commutation losses with respect to the traditional ones in order to optimize this aspect. This paper presents a novel simulation analysis of the Multicarrier Sinusoidal Pulse Width Modulation (MC SPWM) techniques B-Spline functions based to control the switches of five-level single-phase cascaded H-bridge inverter. In order to verify the performance of the converter, the harmonic content of the voltage due to modulation techniques has been taken into account. Results highlight the comparison between different B-Spline functi…
New approach for harmonic mitigation in single-phase five-level CHBMI with fundamental frequency switching
2017
The main objective of this paper is to study and analyse the voltage output waveform of a multilevel inverter, to suggest a new approach for harmonic mitigation improving the converter performance. These last type of converters represent a new technology in the field of DC/AC electrical energy conversion, presenting advantages respect to the traditional converters. In fact, the multilevel power converters present a low harmonic content and a high voltage level. The paper considers a five-level single-phase cascaded H-bridge inverter and fundamental frequency modulation techniques. The voltage waveform analysis has allowed to identify a working area of the converter where there are lowest va…
Experimental analysis with FPGA controller-based of MC PWM techniques for three-phase five level cascaded H-bridge for PV applications
2016
The FPGA represents a valid solution for the design of control systems for inverters adopted in the field of PV systems because of their high flexibility of use. This paper presents an experimental analysis of the MC SPWM techniques for a three-phase, five-level, cascaded H-Bridge inverter with FPGA controller-based. Several control algorithms are implemented by means of the VHDL programming language and the output voltage waveforms obtained from the main PWM techniques are compared in terms of THD%. Simulation and experimental results are analysed, compared and discussed.