1,669 research outputs found
81 fJ/bit energy-to-data ratio of 850 nm vertical-cavity surface-emitting lasers for optical interconnects
No full textThis article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 98, 231106 (2011) and may be found at https://doi.org/10.1063/1.3597799.Extremely energy-efficient oxide-confined high-speed 850 nm vertical-cavity surface-emitting lasers for optical interconnects are presented. Error-free performance at 17 and 25 Gb/s via a 100 m multimode fiber link is demonstrated at record high dissipation-power-efficiencies of up to 69 fJ/bit (<0.1mW/Gbps) and 99 fJ/bit, respectively. These are the most power efficient high-speed directly modulated light sources reported to date. The total energy-to-data ratio is 83 fJ/bit at 25°C and reduces to 81 fJ/bit at 55°C. These results were obtained without adjustment of driving conditions. A high -factor of 12.0GHz/(mA)0.5 and a -factor of 0.41 ns are measured.EC/FP7/224211/EU/VISIT - Vertically Integrated Systems for Information Transfer/VISITDFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, Bauelement
Evidential English adverbials and their French equivalents in a specialised parallel corpus
No full textThis research paper investigates the translation procedures applied to English evidential adverbials within a parallel corpus of specialized technical information in English and French aimed at popularisation. We analyse the strategies deployed by translators to ensure a natural reading in the target language, taking into consideration variation in metadiscourse functions. Corpus linguistics methods are used to analyse adverbial positioning, morphological characteristics, metadiscourse functions, and translation strategies. Our anticipated conclusions highlight the manifold functions of evidential adverbials, from enhancing meaning to conveying the author's attitude, often influenced by cultural and professional factors, resulting in variable translation strategies
The use of cinema as a tool for the inclusion of cultural elements in the classroom of English as a foreign language
No full textEn el presente estudio se realiza una propuesta didáctica para la introducción del componente cultural en la enseñanza del inglés como lengua extranjera utilizando el cine como herramienta didáctica. El uso de fragmentos de diferentes películas tendrá como resultado una clase más atractiva para los alumnos con una visión novedosa y diferente y, al mismo tiempo, promovemos el desarrollo de la capacidad investigadora del alumnado desde la etapa de educación obligatoria. En este estudio se realiza una propuesta metodológica donde, basándonos en el marco teórico presentado, se ofrecen algunos ejemplos de actividades basadas en el empleo del cine como principal herramienta de enseñanza.In this study, we offer a learning proposal based on the use of cinema as a teaching resource with the aim of introducing the cultural component in the class of English as a foreign language. The use of specific film's fragments would have more attractive and motivating lessons promoting the students' autonomy as a result. First, we present a short theoretical framework, and then, based on it, a learning proposal is given, which promotes the development of certain competences. A sample of activities using the cinema as the main didactic tool is also offered.6244ESC
Single-drive high-speed lumped depletion-type modulators toward 10 fJ/bit energy consumption
No full textReduction of modulator energy consumption to 10 fJ/bit is essential for the sustainable development of communication systems. Lumped modulators might be a viable solution if instructed by a complete theory system. Here, we present a complete analytical electro-optic response theory, energy consumption analysis, and eye diagrams on absolute scales for lumped modulators. Consequently the speed limitation is understood and alleviated by single-drive configuration, and comprehensive knowledge into the energy dependence on structural parameters significantly reduces energy consumption. The results show that silicon modulation energy as low as 80.8 and 21.5 fJ/bit can be achieved at 28 Gbd under 50 and 10 Omega impedance drivers, respectively. A 50 Gbd modulation is also shown to be possible. The analytical models can be extended to lumped modulators on other material platforms and offer a promising solution to the current challenges of modulation energy reduction. (C) 2017 Chinese Laser PressNational Natural Science Foundation of China (NSFC) [61120106012]SCI(E)ARTICLE2134-142
Author Arna Bontemps reads to children at the East Winston Branch Library, 1956.
No full textAuthor Arna Bontemps reads to children at the East Winston Branch Library, 1956
SPIN AND CHARGE FLUCTUATIONS IN ITINERANT-ELECTRON MAGNETISM - A VARIATIONAL FUNCTIONAL-INTEGRAL APPROXIMATION
No full textThe single-site spin-fluctuation theory of metallic magnetism developed by Hubbard and Hasegawa is modified and extended to investigate the effects of spin and charge fluctuations on the magnetic properties at finite temperature. The key point of our scheme is to adopt a continuous decomposition of the interacting part of the Hubbard Hamiltonian in the Stratonovich-Hubbard transformation, resulting in the separation of the charge fluctuations from the spin fluctuations. This separation makes a better description for the contrary nature between the two types of fluctuations. In order to remove the ambiguity, a variational principle is introduced to determine the appropriate form of the decomposition of the Hubbard model. The ground-state properties, the Curie temperature, the magnetization, and the paramagnetic susceptibility, etc., at finite temperature are calculated and compared with the Hasegawa theory. The improvement of the Curie temperature is significant, and better behavior of the temperature dependence of the magnetization is obtained.Physics, Condensed MatterSCI(E)6ARTICLE1712795-128044
Two-Photon AMPK and ATP Imaging Reveals Metabolic Recovery in Mouse Rod Photoreceptor Cells
No full textThe title of publisher's version: Two-photon AMPK and ATP imaging reveals the bias between rods and cones in glycolysis utility.In vertebrates, retinal rod and cone photoreceptor cells rely significantly on glycolysis. Lactate released from photoreceptor cells fuels neighboring retinal pigment epithelium cells and Müller glial cells through oxidative phosphorylation. To understand this highly heterogeneous metabolic environment around photoreceptor cells, single-cell analysis is needed. Here, we visualized cellular AMP-activated protein kinase (AMPK) activity and ATP levels in the retina by two-photon microscopy. Transgenic mice expressing a hyBRET-AMPK biosensor were used for measuring the AMPK activity. GO-ATeam2 transgenic mice were used for measuring the ATP level. Temporal metabolic responses were successfully detected in the live retinal explants upon drug perfusion. A glycolysis inhibitor, 2-deoxy-d-glucose (2-DG), activated AMPK and reduced ATP. These effects were clearly stronger in rods than in cones. Notably, rod AMPK and ATP started to recover at 30 min from the onset of 2-DG perfusion. Consistent with these findings, ex vivo electroretinogram recordings showed a transient slowdown in rod dim flash responses during a 60-min 2-DG perfusion, whereas cone responses were not affected. Based on these results, we propose that cones surrounded by highly glycolytic rods become less dependent on glycolysis, and rods also become less dependent on glycolysis within 60 min upon the glycolysis inhibition
Analysis of the linguistic expression I think in a corpus of late Modern English scientific texts
No full textEste trabajo trata sobre la relación entre modalidad y evidencialidad. Está centrado
específicamente en el uso de la expresión I think en combinación con otros elementos
modales, así como los posibles efectos pragmáticos observados en muestras de textos
obtenidas del Coruña Corpus of English Scientific Writing. Asimismo, analizamos si la variable
de disciplina podría tener algún efecto sobre las funciones que la expresión lleva a cabo
en estos textos. Aunque todavía queda mucho por investigar en textos académicos desde
una perspectiva diacrónica, hay algunos estudios previos sobre elementos de
posicionamiento realizados en el ámbito de la pragmática histórica (cf. Gray, Biber y
Hiltunen 2011; Moskowich and Crespo 2014; Alonso-Almeida 2015; Álvarez-Gil, 2017,
2018, 2019). Siguiendo esta tradición, nos centramos en la expresión I think, siguiendo el
trabajo de van der Auwera y Plungian (1998) para la descripción de la modalidad y los
tipos modales.The present paper deals with the relationship between modality and evidentiality,
focussed specifically on the use of the expression I think in combination with other modal
devices, as well as the possible pragmatic effects observed in text samples obtained from
the Coruña Corpus of English Scientific Writing and whether the variable of discipline might
have some effect on the functions the expression represents in these texts. Even if much
research is still to be done in academic texts from a diachronic perspective, there are
some previous studies on stance devices carried out within the arena of historical
pragmatics (cf. Gray, Biber and Hiltunen 2011; Moskowich and Crespo 2014; Alonso-
Almeida 2015; Álvarez-Gil 2017, 2018, 2019). Following this tradition, we focus on the
expression I think, following the work of van der Auwera and Plungian (1998) for the
description of modality and modal types..574414ESC
A low noise, low power dynamic amplifier with common mode detect and a low power, low noise comparator for pipelined SAR-ADC
No full textThis thesis presents a high gain, low noise and low power dynamic residue amplifier and a low power, low noise dynamic comparator designed in TSMC 28nm process for a two step Pipelined SAR-ADC. The cascoded integrator dynamic residue amplifier (CIDRA) achieves a gain of 30dB with THD of 47dB (11 mV pp input). The input referred noise across tem- perature and process corner is 55 µV and it operates at a frequency of 500MHz while the energy consumption is 390 fJ. The low power and low noise pseudo-latch preamp dynamic comparator (PLPDC) shows a delay of 250pSec for a differential input of 16 pV and consumes 91 fJ (current is 91 µA for 100 MHz clock) of energy. The input referred offset is 4 mV (?).Microelectronics & Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc
Cryogenic Comparator Characterization and Modeling for a Cryo-CMOS 7b 1-GSa/s SAR ADC
No full textThis paper reports the experimental characterization and modelling of a stand-Alone StrongARM comparator at both room temperature (RT) and cryogenic temperature (4.2 K). The observed 6-dB improvement in the comparator input noise at 4.2 K is attributed to the reduction of the thermal noise and to the suppressed shot noise in the MOS transistors becoming dominant at cryogenic temperature. The proposed model is employed in the design of a loop-unrolled 2\times time-interleaved 1-GSa/s 7b SAR ADC for spin-qubit readout. As predicted by the comparator model, the ADC is noise-limited at RT to a SNDR of 38.2 dB at Nyquist input, while this improves to 41.1 dB at 4.2 K, now limited by distortion, thus resulting in the state-of-The-Art FoMw for cryo-CMOS ADC of 20.9 fJ/conv-step. Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.QCD/Sebastiano LabElectrical Engineering, Mathematics and Computer ScienceElectronicsQuantum Circuit Architectures and Technolog
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