Stillness: A meditation in new media art

While technology is often seen as a noisy, impatient and pervasive aspect of our lives, this practice-led research project investigated the counter proposition–that we might be able to evoke sensations of stillness through technology-mediated artworks. Investigations into stillness were informed by Buddhism, phenomenology, and experiences of meditation and the practice of archery. By combining visual art, performance, installation, video and interaction design, a series of experimental, interdisciplinary artworks were produced and exhibited to evoke a sense of stillness and to impel audiences to consider the form and nature of stillness in relation to time, space and motion.

Words as Events : Cretan Mantinádes in Performance and Composition

Words as Events introduces the tradition of short, communicative rhyming couplets, the mantinádes, which are still sung and recited in a variety of performance situations on the island of Crete. The local focus on communicative economy and artistry is further examined in an in-depth analysis of the processes and ideals of composition. Short genres of oral poetry have been widely neglected in folklore research; however, their demand for structural and semantic coherence as well as their dialogic nature appeals to very different human needs from those of the longer poems. In contemporary Crete, poems also appear in written contexts, they are submitted to modern mass media, and people widely exchange them as text messages. By striving to understand the tradition during a period of change, this study analyzes the larger principles that ground the communication, self-expression and creativity in the genre. The aim of this research is thus twofold: to present this specific register of dialogic oral poetry as well as to create a theoretical approach sensitive to the creativity of such short registers. The study is based on long-term ethnographic fieldwork conducted in Crete between the years 1997 2009. An important aspect of the methodology was to create long-term ties with a number of key-informants who composed mantinádes. The interdisciplinary theoretical and methodological basis for this analysis is in the contemporary Finnish and international research on oral poetry and on anthropological research on communicative speech genres. These theoretical insights are extended by addressing questions of spontaneity and individual agency. Since mantinádes are at the same time a model for composition and a reserve of poems in fixed form, the aesthetics and objectives of performance and composition are also plural. In a traditional singing event, the basic motivation for the singers is to provide a meaningful contribution to a selected theme, which is the shared topic of the poetic dialogue. Consequently, similar topics giving rise to poetic associations can be encountered during various moments of everyday life: the dialogic nature is embodied in the tradition to such degree that it also arises in the performances and composition of single poems and outside of any institutionalized performance arenas. Therefore, as this study discusses in detail, even the apparently non-contextualized poems recited between locals or occurring in the contemporary mass media arenas, are understood and evaluated as utterances that provide an individual perspective within a certain dialogue.

HFinFET: A Scalable, High Performance, Low Leakage Hybrid n-Channel FET

In this letter, we propose the design and simulation study of a novel transistor, called HFinFET, which is a hybrid of an HEMT and a FinFET, to obtain excellent performance and good OFF-state control. Followed by the description of the design, 3-D device simulation has been performed to predict the characteristics of the device. The device has been benchmarked against published state of the art HEMT as well as planar and nonplanar Si n-MOSFET data of comparable gate length using standard benchmarking techniques.

Rate Control State-of-the-art Survey

The majority of Internet traffic use Transmission Control Protocol (TCP) as the transport level protocol. It provides a reliable ordered byte stream for the applications. However, applications such as live video streaming place an emphasis on timeliness over reliability. Also a smooth sending rate can be desirable over sharp changes in the sending rate. For these applications TCP is not necessarily suitable. Rate control attempts to address the demands of these applications. An important design feature in all rate control mechanisms is TCP friendliness. We should not negatively impact TCP performance since it is still the dominant protocol. Rate Control mechanisms are classified into two different mechanisms: window-based mechanisms and rate-based mechanisms. Window-based mechanisms increase their sending rate after a successful transfer of a window of packets similar to TCP. They typically decrease their sending rate sharply after a packet loss. Rate-based solutions control their sending rate in some other way. A large subset of rate-based solutions are called equation-based solutions. Equation-based solutions have a control equation which provides an allowed sending rate. Typically these rate-based solutions react slower to both packet losses and increases in available bandwidth making their sending rate smoother than that of window-based solutions. This report contains a survey of rate control mechanisms and a discussion of their relative strengths and weaknesses. A section is dedicated to a discussion on the enhancements in wireless environments. Another topic in the report is bandwidth estimation. Bandwidth estimation is divided into capacity estimation and available bandwidth estimation. We describe techniques that enable the calculation of a fair sending rate that can be used to create novel rate control mechanisms.

Automatic Tonic Identification in Indian Art Music: Approaches and Evaluation

The tonic is a fundamental concept in Indian art music. It is the base pitch, which an artist chooses in order to construct the melodies during a rg(a) rendition, and all accompanying instruments are tuned using the tonic pitch. Consequently, tonic identification is a fundamental task for most computational analyses of Indian art music, such as intonation analysis, melodic motif analysis and rg recognition. In this paper we review existing approaches for tonic identification in Indian art music and evaluate them on six diverse datasets for a thorough comparison and analysis. We study the performance of each method in different contexts such as the presence/absence of additional metadata, the quality of audio data, the duration of audio data, music tradition (Hindustani/Carnatic) and the gender of the singer (male/female). We show that the approaches that combine multi-pitch analysis with machine learning provide the best performance in most cases (90% identification accuracy on average), and are robust across the aforementioned contexts compared to the approaches based on expert knowledge. In addition, we also show that the performance of the latter can be improved when additional metadata is available to further constrain the problem. Finally, we present a detailed error analysis of each method, providing further insights into the advantages and limitations of the methods.

Da rua para a rua: percursos para uma performance

Partindo do corpo que caminha pela cidade, com ou sem rumo, a presente dissertação procura investigar as relações que cercam essa simples ação, levando em consideração, inclusive, a roupa que esse homem veste. O corpo é discutido, tentando encontrar modos mais viscerais para um contato com a realidade operante e arquitetar novas narrativas. A caminhada é o mais simples ato para a (des)apropriação de territórios a serem experimentados. A roupa é a fronteira entre o corpo e a cidade. A camuflagem aparece como um meio eficiente de contactar o corpo com o meio e sua lógica atravessa nosso contato com o mundo. As cidades, suas ruas e espaços públicos solicitam o uso coletivo e se entregam satisfeitos às intervenções urbanas. O texto segue visitando trabalhos que cruzam esse conjunto, buscando desvios nos espaços e resignificando objetos abundantes que se apresentam sem finalidade, procurando inverter lógicas vigentes para realizar outros usos do corpo, da roupa e da cidade

Simulated superior performance of superjuction bipolar transistors

This paper presents for the first time an investigation and comparison of the superjunction IGBT (SJBT) as proposed in [1,2] and the current state of art Field Stop IGBT [3,4]. Simulation results indicate the superior performance of the superjunction IGBT under switching conditions. For the same conditions, at a collector current density of 100A/cm2 and on-state voltage 1.6 V the switching off losses for a SJBT and Field-Stop IGBT are 1 and 4.5 mJ/cm 2 respectively. © 2006 IEEE.

Towards probabilistic performance metrics for climate change impact studies

This paper explores the current state-of-the-art in performance indicators and use of probabilistic approaches used in climate change impact studies. It presents a critical review of recent publications in this field, focussing on (1) metrics for energy use for heating and cooling, emissions, overheating and high-level performance aspects, and (2) uptake of uncertainty and risk analysis. This is followed by a case study, which is used to explore some of the contextual issues around the broader uptake of climate change impact studies in practice. The work concludes that probabilistic predictions of the impact of climate change are feasible, but only based on strict and explicitly stated assumptions. © 2011 Elsevier B.V. All rights reserved.

A performance evaluation of volumetric 3D interest point detectors

This paper presents the first performance evaluation of interest points on scalar volumetric data. Such data encodes 3D shape, a fundamental property of objects. The use of another such property, texture (i.e. 2D surface colouration), or appearance, for object detection, recognition and registration has been well studied; 3D shape less so. However, the increasing prevalence of 3D shape acquisition techniques and the diminishing returns to be had from appearance alone have seen a surge in 3D shape-based methods. In this work, we investigate the performance of several state of the art interest points detectors in volumetric data, in terms of repeatability, number and nature of interest points. Such methods form the first step in many shape-based applications. Our detailed comparison, with both quantitative and qualitative measures on synthetic and real 3D data, both point-based and volumetric, aids readers in selecting a method suitable for their application. © 2012 Springer Science+Business Media, LLC.

High performance uncooled 1.3μm VCSELs for RF-over-fiber applications

Uncooled directly-modulated 1.3μm VCSELs are shown to exhibit dynamic range, linearity and noise performance required for wireless LAN applications. A multimode fiber based WLAN 802.11b system shows performances comparable to systems with state-of-the-art DFB lasers. © 2005 Optical Society of America.

High performance uncooled 1.3μm VCSELs for RF-over-fiber applications

Uncooled directly-modulated 1.3μm VCSELs are shown to exhibit dynamic range, linearity and noise performance required for wireless LAN applications. A multimode fiber based WLAN 802.11b system shows performances comparable to systems with state-of-the-art DFB lasers. © 2005 Optical Society of America.

Theoretical design and performance of InxGa1-xN two-junction solar cells

The efficiencies of InxGa1-xN two-junction solar cells are calculated with various bandgap combinations of subcells under AM1.5 global, AM1.5 direct and AM0 spectra. The influence of top-cell thickness on efficiency has been studied and the performance of InxGa1-xN cells for the maximum light concentration of various spectra has been evaluated. Under one-sun irradiance, the optimum efficiency is 35.1% for the AM1.5 global spectrum, with a bandgap combination of top/bottom cells as 1.74 eV/1.15 eV. And the limiting efficiency is 40.9% for the highest light concentration of the AM1.5 global spectrum, with the top/bottom cell bandgap as 1.72 eV/1.12 eV.

High-performance 2 mm gate width GaNHEMTs on 6H-SiC with output power of 22.4 W @ 8 GHz

Optimized AlGaN/AlN/GaN high electron mobility transistors (HEMTs) structures were grown on 2-in semi-insulating (SI) 6H-SiC substrate by metal-organic chemical vapor deposition (MOCVD). The 2-in. HEMT wafer exhibited a low average sheet resistance of 305.3 Omega/sq with a uniformity of 3.85%. The fabricated large periphery device with a dimension of 0.35 pm x 2 nun demonstrated high performance, with a maximum DC current density of 1360 mA/mm, a transconductance of 460 mS/mm, a breakdown voltage larger than 80 V, a current gain cut-off frequency of 24 GHz and a maximum oscillation frequency of 34 GHz. Under the condition of continuous-wave (CW) at 9 GHz, the device achieved 18.1 W output power with a power density of 9.05 W/mm and power-added-efficiency (PAE) of 36.4%. While the corresponding results of pulse condition at 8 GHz are 22.4 W output power with 11.2 W/mm power density and 45.3% PAE. These are the state-of-the-art power performance ever reported for this physical dimension of GaN HEMTs based on SiC substrate at 8 GHz. (c) 2008 Elsevier Ltd. All rights reserved.

Fabrication of nano-patterned sapphire substrates and their application to the improvement of the performance of GaN-based LEDs

Nano-patterned sapphire substrates (NPSSs) were fabricated by a chemical wet etching technology using nano-sized SiO2 as masks. The NPSS was applied to improve the performance of GaN-based light emitting diodes (LEDs). GaN-based LEDs on NPSSs were grown by metal organic chemical vapour deposition. The characteristics of LEDs grown on NPSSs and conventional planar sapphire substrates were studied. The light output powers of the LEDs fabricated on NPSSs were considerably enhanced compared with that of the conventional LEDs grown on planar sapphire substrates.

A mini-staged multi-stacked quantum cascade laser for improved optical and thermal performance

In this paper, a mini-staged multi-stacked quantum cascade laser structure with a designed wavelength of 4.7 mu m is presented. By introducing five 0.5 mu m thick high thermal conductivity InP interbuffer layers, the 60-stages active region core of the quantum cascade laser is divided into six equal parts. Based on simulation, this kind of quantum cascade laser with a 10 mu m ridge width gives nearly circular two-dimensional far-field distribution (FWHM = 32.8 degrees x 29 degrees) and good beam quality parameters M-2 = 1.32 x 1.31 in the fast axis (growth direction) and the slow axis (lateral direction). Due to the enhancement of lateral heat extraction through the interbuffer layers, compared to the conventional structure, a decrease of about 5-6% for the maximum temperature in the active region core of the mini-staged multi-stacked quantum cascade laser with indium-surrounded and gold-electroplated packaging profiles is obtained at all possible dissipated electrical power levels.