5,937 research outputs found
Alternative conducted immunity tests
Conducted immunity tests are always performed by the use of CDNs in laboratories in accordance with the standard EN61000-4-6. However, it is not always possible to use CDNs because of some limitations. If the EUT (Equipment Under Test) has large dimensions or high currents, it is not, most of the time, possible to send it to an EMC laboratory or to use CDNs during the test. As a consequence, usage of BCI probes is inevitable in industry. In this paper, we compared the laboratory setup installed with CDNs and alternative setups installed directly on mains without any CDNs in terms of loop impedances and injected loop currents. We also established a link based on the loop impedances and the injected currents on the test loops between the two setups. Finally, a first serious step was taken to establish the fundamentals of alternative conducted immunity tests based on the impedance measurements of test loops for industry.Postprint (published version
SIDO Buck converter with independent outputs
The portable electronics market is rapidly migrating towards more compact devices requiring multiple high-integrity
high-efficiency voltage supplies for empowering the systems. This paper demonstrates a single inductor used in a buck converter with two output voltages from an input battery with voltage of value 3V.
The main target is low cross regulation between the two outputs to supply independent load current levels while maintaining desired output voltage values well within a ripple that is set by adaptive hysteresis levels. A reverse current detector to avoid negative current flowing through the inductor prevents efficiency degradation at light load.Postprint (published version
SIDO Buck converter with independent outputs
The portable electronics market is rapidly migrating towards more compact devices requiring multiple high-integrity
high-efficiency voltage supplies for empowering the systems. This paper demonstrates a single inductor used in a buck converter with two output voltages from an input battery with voltage of value 3V.
The main target is low cross regulation between the two outputs to supply independent load current levels while maintaining desired output voltage values well within a ripple that is set by adaptive hysteresis levels. A reverse current detector to avoid negative current flowing through the inductor prevents efficiency degradation at light load.Postprint (published version
Evaluación de la cronología dentaria en grupos wichi, toba y criollos del Gran Chaco (provincia de Formosa)
Se realizó el análisis de la cronología de erupción dentaria como una evaluación de maduración funcional en individuos pertenecientes a comunidades wichí, toba y crillas del Gran Chaco (provincia de Formosa, Argentina). Se tuvieron en cuenta los elementos dentarios presentes en cada hemiarcada izquierda y el orden de erupción. El objetivo del presente trabajo fue examinar el comportamiento de estas variables en la población infantil de ambos sexos de las distintas comunidades. La muestra estuvo integrada por 159 individuos entre 6 y 12 años. La metodología aplicada fue la del conteo de las piezas dentarias individuales. Los datos fueron volcados en una ficha odontológica pertinente. Se analizó comparativamente el orden de erupción en cada muestra investigada. Resultados: a) diferencias de erupción entre los wichí, toba y criollos; b) alteración en el orden de erupción, en el segundo premolar y los segundos molares y c) variación de erupción de las niñas con respecto a los varones. Concluimos que los grupos pertenecientes a la misma zona geográfica, pero con distinto nivel socioeconómico, muestran diferencias en la cronología dentaria, lo cual estaría indicando una influencia ambiental sobre el determinante genético
Cellular automaton supercolliders
Gliders in one-dimensional cellular automata are compact groups of
non-quiescent and non-ether patterns (ether represents a periodic background)
translating along automaton lattice. They are cellular-automaton analogous of
localizations or quasi-local collective excitations travelling in a spatially
extended non-linear medium. They can be considered as binary strings or symbols
travelling along a one-dimensional ring, interacting with each other and
changing their states, or symbolic values, as a result of interactions. We
analyse what types of interaction occur between gliders travelling on a
cellular automaton `cyclotron' and build a catalog of the most common
reactions. We demonstrate that collisions between gliders emulate the basic
types of interaction that occur between localizations in non-linear media:
fusion, elastic collision, and soliton-like collision. Computational outcomes
of a swarm of gliders circling on a one-dimensional torus are analysed via
implementation of cyclic tag systems
A cone-continuity constraint qualification and algorithmic consequences
PRONEX - PROGRAMA DE APOIO A NÚCLEOS DE EXCELÊNCIAFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOREvery local minimizer of a smooth constrained optimization problem satisfies the sequential approximate Karush-Kuhn-Tucker (AKKT) condition. This optimality condition is used to define the stopping criteria of many practical nonlinear programming algorithms. It is natural to ask for conditions on the constraints under which AKKT implies KKT. These conditions will be called strict constraint qualifications (SCQs). In this paper we define a cone-continuity property (CCP) that will be shown to be the weakest possible SCQ. Its relation to other constraint qualifications will also be clarified. In particular, it will be proved that CCP is strictly weaker than the constant positive generator constraint qualification.Every local minimizer of a smooth constrained optimization problem satisfies the sequential approximate Karush-Kuhn-Tucker (AKKT) condition. This optimality condition is used to define the stopping criteria of many practical nonlinear programming algorithms. It is natural to ask for conditions on the constraints under which AKKT implies KKT. These conditions will be called strict constraint qualifications (SCQs). In this paper we define a cone-continuity property (CCP) that will be shown to be the weakest possible SCQ. Its relation to other constraint qualifications will also be clarified. In particular, it will be proved that CCP is strictly weaker than the constant positive generator constraint qualification26196110PRONEX - PROGRAMA DE APOIO A NÚCLEOS DE EXCELÊNCIAFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORPRONEX - PROGRAMA DE APOIO A NÚCLEOS DE EXCELÊNCIAFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORE-26/111.449/2010-APQ12013/07375-0; 2012/20339-0; 2013/05475-7304618/2013-6; 482549/2013-0; 303750/2014-6; 303013/2013-3sem informaçã
Recent Overview of Solar Photocatalysis and Solar Photo-Fenton Processes for Wastewater Treatment
This literature research, although not exhaustive, gives perspective to solar-driven photocatalysis, such as solar photo-Fenton and TiO2 solar photocatalysis, reported in the literature for the degradation of aqueous organic pollutants. Parameters that influence the degradation and mineralization of organics like catalyst preparation, type and load of catalyst, catalyst phase, pH, applied potential, and type of organic pollutant are addressed. Such parameters may also affect the photoactivity of the catalysts used in the studied solar processes. Solar irradiation is a renewable, abundant, and pollution-free energy source for low-cost commercial applications. Therefore, these solar processes represent an environmentally friendly alternative mainly because the use of electricity can be decreased/avoided
Reconstructing the impact of human activities in a NW Iberian Roman mining landscape for the last 2500 years
This article was made available through the Brunel Open Access Publishing Fund.Little is known about the impact of human activities during Roman times on NW Iberian mining landscapes beyond the geomorphological transformations brought about by the use of hydraulic power for gold extraction. We present the high-resolution pollen record of La Molina mire, located in an area intensely used for gold mining (Asturias, NW Spain), combined with other proxy data from the same peat core to identify different human activities, evaluate the strategies followed for the management of the resources and describe the landscape response to human disturbances. We reconstructed the timing and synchronicity of landscape changes of varying intensity and form occurred before, during and after Roman times. An open landscape was prevalent during the local Late Iron Age, a period of relatively environmental stability. During the Early Roman Empire more significant vegetation shifts took place, reflected by changes in both forest (Corylus and Quercus) and heathland cover, as mining/metallurgy peaked and grazing and cultivation increased. In the Late Roman Empire, the influence of mining/metallurgy on landscape change started to disappear. This decoupling was further consolidated in the Germanic period (i.e., Visigothic and Sueve domination of the region), with a sharp decrease in mining/metallurgy but continued grazing. Although human impact was intense in some periods, mostly during the Early Roman Empire, forest regeneration occurred afterwards: clearances were local and short-lived. However, the Roman mining landscape turned into an agrarian one at the onset of the Middle Ages, characterized by a profound deforestation at a regional level due to a myriad of human activities that resulted in an irreversible openness of the landscape. © 2014 The Authors
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