Passivation of Grid-Following VSCs: A Comparison Between Active Damping and Multi-Sampled PWM

This article compares different strategies used to enhance the stability properties of grid-following voltage-source converters (VSCs). Because of digital delays, VSC admittance exhibits a nonpassive zone, which introduces negative damping and may destabilize the grid-connected operation. It is shown that typically used active damping (AD) strategies only bring positive impact up to a certain frequency, while deteriorating admittance properties around and above the Nyquist frequency. Multi-sampled pulsewidth modulation (MS-PWM) greatly extends the passive admittance region, using only a single-loop current controller. Experimental admittance measurements are performed on a single-phase VSC, up to twice the switching frequency. Subsequently, different grid-connected scenarios are tested to show that MS-PWM retains stable operation, where AD methods cause instability. This article also offers analytic modeling and experimental measurements of noise propagation for compared strategies. It is shown that derivative-based AD is not highly sensitive; however, MS-PWM offers additional noise suppression

Humanity at first sight: Exploring the relationship between others' pupil size and ascriptions of humanity

Social targets' eyes are a rich source of information: partners with dilated and constricted pupils are perceived positively and negatively, respectively. Here, we tested whether observed pupil size influences the ascription of humanity. In Study 1 (n = 198) participants were asked to attribute positive uniquely human and non-uniquely human traits to ingroup (i.e., university students), derogated (i.e., homeless people) and non-derogated (i.e., Dutch) targets whose pupils varied in size. Results showed higher attribution of uniquely human traits to targets with dilated (vs. constricted) pupils, whereas no difference based on pupil size emerged on the attribution of non-uniquely human traits. The effect was stronger for non-derogated (vs. derogated and ingroup) targets. In Study 2 (n = 117) participants were asked to attribute positive uniquely human and non-uniquely human traits and emotions. Results replicated the effect of pupil size on trait attribution, especially for outgroup (vs. ingroup) members. The effect of pupil size was not qualified by emotions type (uniquely human vs. non uniquely human). Taken together, our findings show that pupil size is interpreted as a cue to attribute humanity to social targets

It is written in the eyes: inferences from pupil size and gaze orientation shape interpersonal liking

Action Contro

How to make stream processing more mainstream

Stream processing has a long history as a way of describing and implementing specific kinds of computational processes. So far, however, it has largely remained an exotic field of endeavor, with relatively small momentum compared to traditional von Neumann computing, and a large variety of programming models, languages, tools, and hardware realizations. However, as sequential machines cease to become faster over time, and future growth in computational speed will clearly derive from an increase in parallelism, the time has come for a general parallel programming model to supplant or complement the von Neumann abstraction

Overview of the MPEG Reconfigurable Video Coding Framework

International audienceVideo coding technology in the last 20 years has evolved producing a variety of different and complex algorithms and coding standards. So far the specification of such standards, and of the algorithms that build them, has been done case by case providing monolithic textual and reference software specifications in different forms and programming languages. However, very little attention has been given to provide a specification formalism that explicitly presents common components between standards, and the incremental modifications of such monolithic standards. The MPEG Reconfigurable Video Coding (RVC) framework is a new ISO standard currently under its final stage of standardization, aiming at providing video codec specifications at the level of library components instead of monolithic algorithms. The new concept is to be able to specify a decoder of an existing standard or a completely new configuration that may better satisfy application-specific constraints by selecting standard components from a library of standard coding algorithms. The possibility of dynamic configuration and reconfiguration of codecs also requires new methodologies and new tools for describing the new bitstream syntaxes and the parsers of such new codecs. The RVC framework is based on the usage of a new actor/ dataflow oriented language called CAL for the specification of the standard library and instantiation of the RVC decoder model. This language has been specifically designed for modeling complex signal processing systems. CAL dataflow models expose the intrinsic concurrency of the algorithms by employing the notions of actor programming and dataflow. The paper gives an overview of the concepts and technologies building the standard RVC framework and the non standard tools supporting the RVC model from the instantiation and simulation of the CAL model to software and/or hardware code synthesis