5,413 research outputs found
"Spring poem" by Desanka Maksimovic. Harmony of sounding and meaning
No full textThe author makes an attempt to observe and evaluate the expressive performance of the artistic text, to apply a linguo-stylistic analysis as an integral part of every interpretative stream of literary work. The article discusses the role and importance of prosodic elements and analyzes the basic stylistic components of the artistic text: composition, forms of narratives, stylistic figures. Such methods could not be applied as isolated and by themselves, but they are intended to examine the complex structure of Spring Poem by Desanka Maksimovic as a whol
"Spring poem" by Desanka Maksimovic. Harmony of sounding and meaning
No full textThe author makes an attempt to observe and evaluate the expressive performance of the artistic text, to apply a linguo-stylistic analysis as an integral part of every interpretative stream of literary work. The article discusses the role and importance of prosodic elements and analyzes the basic stylistic components of the artistic text: composition, forms of narratives, stylistic figures. Such methods could not be applied as isolated and by themselves, but they are intended to examine the complex structure of Spring Poem by Desanka Maksimovic as a whol
Oxalate oxidase and non-enzymatic compounds of the antioxidative system in young Serbian spruce plants exposed to cadmium stress
No full textWe studied changes in the concentrations of ascorbate and glutathione, composition of soluble phenolics, and activity of oxalate oxidase in 75-day-old Serbian spruce plants after exposure to 5 mu M and 50 mu M cadmium for 6-48 h. The presence of OxOx activity in a conifer species is here demonstrated for the first time. Both Cd concentrations induced a decrease of OxOx activity in treated plants in comparison with the control at all sampling dates. The concentrations of reduced glutathione, its oxidized form, and reduced ascorbate in the plants decreased during 48-h treatment with cadmium. Among simple phenolics, only catechin increased significantly during Cd treatment
Ulysses electron distributions fitted with Kappa functions
No full textWe fit Kappa functions to 16,000 velocity distribution functions measured in the solar wind by the electron plasma instrument on board Ulysses. Statistically, the electron distributions are observed to have important high velocity tails in the fast solar wind but are closer to a Maxwellian in the slow wind. We also discuss how this result could support a recent kinetic model of the solar wind proposed by Maksimovic, Pierrard and Lemaire [1997]
A Digital Pulse-Width Modulator for Phase-Shift Operation of Full-Bridge Isolated DC-DC Converters
No full textThis paper presents the concept, implementation
and testing of a digital pulse-width modulator for phase-shift
driving of full-bridge isolated DC-DC converters. The
proposed phase-shift digital modulator employs a hybrid
counter/delay line structure in order to achieve a 1.25 ns
phase-shift resolution with a switching frequency of about
400 kHz on the secondary side, using a clock frequency of
25 MHz. Provisions for programmable dead times for
switching of the bridge legs are included. The modulator is
tested as a part of a digital controller for a full-bridge DC-DC
isolated converter supplied from a 320 V DC bus with a 20 V-
180 V, 2 A programmable output
Adaptive Non-Inverting Buck-Boost IC with On-Chip Sigma-Delta ADC for Portable Applications
No full textThis paper focuses on a mixed-signal IC realization of
a digitally controlled power converter which steps up/down from
2.7-5.5 V to 1-3.6 V for battery powered portable applications. In
particular, in this work a Σ-Δ modulated digital pulse-width
modulator is combined with a low power second-order multi-bit
Σ-Δ ADC in a 0.5 μm CMOS process. It is shown that precise
output voltage positioning in buck, boost and buck/boost
transition modes can be achieved. The quiescent current
consumption of the IC is 700 μA. Experimentally observed
efficiency of the converter is reported for 30 mA-360 mA load
current with peak efficiency of 94%
Sensorless Current Sharing in Digitally Controlled Two-Phase Buck DC-DC Converters
No full textThis paper describes a current sharing technique
for digitally controlled two-phase buck DC-DC converters where
pulse width and resistance mismatches are digitally compensated
to achieve approximately equal current sharing without sensing
currents. Effects of various non-idealities on the current sharing
performance are discussed and corresponding mitigation
techniques are presented. An extension to converters with more
than two phases is discussed. Experimental results are shown for
a two-phase synchronous buck converter with 6V input voltage,
and 1.3 V, 0 − 20 A output
Digitally Controlled Distributed Multiphase DC-DC Converters
No full textThis paper describes a distributed master-slave
multiphase DC-DC converter architecture and related digital
control and communication techniques. In the distributed
master-slave architecture, all converter modules are identical,
but one module operates as the master. The master module
communicates its voltage error and current data over a singlewire
serial bus to remove the voltage sensing mismatch and to
accomplish active current sharing among the modules.
Experimental results are shown for a 5 V-to-12 V input, 1.3 V,
20 A output two-phase synchronous buck converter
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