646 research outputs found

    Developing vanadium redox flow technology on a 9-kW 26-kWh industrial scale test facility: Design review and early experiments

    Get PDF
    Redox Flow Batteries (RFBs) have a strong potential for future stationary storage, in view of the rapid expansion of renewable energy sources and smart grids. Their development and future success largely depend on the research on new materials, namely electrolytic solutions, membranes and electrodes, which is typically conduced on small single cells. A vast literature on these topics already exists. However, also the technological development plays a fundamental role in view of the successful application of RFBs in large plants. Despite that, very little research is reported in literature on the technology of large RFB systems. This paper presents the design, construction and early operation of a vanadium redox flow battery test facility of industrial size, dubbed IS-VRFB, where such technologies are developed and tested. In early experiments a peak power of 8.9 kW has been achieved with a stack specific power of 77Wkg−1. The maximum tested current density of 635 mA cm−2 has been reached with a cell voltage of 0.5 V, indicating that higher values can be obtained. The test facility is ready to be complemented with advanced diagnostic devices, including multichannel electrochemical impedance spectroscopy for studying aging and discrepancies in the cell behaviors

    ECFA Detector R&D Panel, Review Report

    Full text link
    Two special calorimeters are foreseen for the instrumentation of the very forward region of an ILC or CLIC detector; a luminometer (LumiCal) designed to measure the rate of low angle Bhabha scattering events with a precision better than 103^{-3} at the ILC and 102^{-2} at CLIC, and a low polar-angle calorimeter (BeamCal). The latter will be hit by a large amount of beamstrahlung remnants. The intensity and the spatial shape of these depositions will provide a fast luminosity estimate, as well as determination of beam parameters. The sensors of this calorimeter must be radiation-hard. Both devices will improve the e.m. hermeticity of the detector in the search for new particles. Finely segmented and very compact electromagnetic calorimeters will match these requirements. Due to the high occupancy, fast front-end electronics will be needed. Monte Carlo studies were performed to investigate the impact of beam-beam interactions and physics background processes on the luminosity measurement, and of beamstrahlung on the performance of BeamCal, as well as to optimise the design of both calorimeters. Dedicated sensors, front-end and ADC ASICs have been designed for the ILC and prototypes are available. Prototypes of sensor planes fully assembled with readout electronics have been studied in electron beams.Comment: 61 pages, 51 figure

    LASER Tech Briefs, Spring 1994

    Get PDF
    Topics in this Laser Tech Brief include: Electronic Components and Circuits. Electronic Systems, Physical Sciences, Materials, Mechanics, Fabrication Technology, and books and reports

    Television Playout Development Towards Flexible IT-based Solutions

    Get PDF
    The purpose of this study was to update television playout system. An Estonian television and radio network operator Levira playout centre needed expansion in infrastructure to be able to accommodate larger channel count. Renewals of media asset management and automation systems were also required to handle requirements of the larger channel count and to automate processes. Television playout systems and solutions are going through big changes. These changes reflect partially new developments in the whole broadcasting industry and the way people use video, as well as changes and development in other areas of technology, especially in IT. These changes do not come without challenges with new workflows and ways of operating. These projects were to be done not only for current needs but also to be ready for the coming years. This was taken into consideration on system design and planning as well as on choosing the partners for the projects. As a result of this study, an up to date playout centre was designed with flexible IT based solutions that are easy to update and customize for varying needs of different television channels. Playout centre has room to grow and it is ready for requirements of future without need for major changes in the system.Työn tavoitteena oli television lähetyskeskuksen järjestelmän päivittäminen. Virolaisen television ja radion lähetysverkkotoimija Leviran lähetyskeskus tarvitsi laajennuksen olemassa olevaan järjestelmään, jotta se pystyisi lähettämään suuremman määrän kanavia. Myös lähetyskeskuksen medianhallinta- ja automaatiojärjestelmät täytyi päivittää tämän suuremman kanavamäärän tukemiseksi ja työnkulun tehostamiseksi. Television lähetysjärjestelmät ja ratkaisut käyvät läpi isoja muutoksia. Nämä muutokset heijastuvat osin koko televisiotoiminnan muutoksesta ja siitä, miten katsojat ylipäätään käyttävät videota ja osin informaatioteknologian (IT) kehityksestä. Se on selvää, että muutokset tuovat uusia haasteita, edellyttävät täysin uudenlaisten työnkulkujen ja ajatusmallien omaksumista. Molemmat projektit toteutettiin ottaen huomioon tämän hetken tarpeet tiedostopohjaisen työnkulun ja kasvavan kanavamäärän tuoman kapasiteettivaatimusten suhteen sekä ennen kaikkea lähivuosien mahdolliset vaatimukset muuttuvien jakelukanavien osalta. Systeemin suunnittelu ja yhteistyökumppaneiden valinta painotettiin sen mukaisesti. Toteutettuna lopputuloksena on television lähetyskeskusjärjestelmä, joka pohjautuu helposti päivitettäviin ja eri televisiokanavien vaihteleviin tarpeisiin mukautuviin IT-laitteistoihin. Järjestelmällä on tilaa kasvaa sekä kehittyä tulevaisuuteen ilman välitöntä tarvetta merkittäviin systeemitason muutoksiin

    The 1995 NASA guide to graduate support

    Get PDF
    The future of the United States is in the classrooms of America and tomorrow's scientific and technological capabilities are derived from today's investments in research. In 1980, NASA initiated the Graduate Student Researchers Program (GSRP) to cultivate additional research ties to the academic community and to support promising students pursuing advanced degrees in science and engineering. Since then, approximately 1300 students have completed the program's requirements. In 1987, the program was expanded to include the Underrepresented Minority and Disabled Focus (UMDF) Component. This program was designed to increase participation of underrepresented groups in graduate study and research and, ultimately, in space science and aerospace technology careers. Approximately 270 minority students have completed the program's requirements while making significant contributions to the nation's aerospace efforts. Continuing to expand fellowship opportunities, NASA announced the Graduate Student Fellowships in Global Change Research in 1990. Designed to support the rapid growth in the study of earth as a system, more than 250 fellowships have been awarded. And, in 1992, NASA announced opportunities in the multiagency High Performance Computing and Communications (HPCC) Program designed to accelerate the development and application of massively parallel processing. Approximately five new fellowships will be awarded yearly. This booklet will guide you in your efforts to participate in programs for graduate student support

    Advanced photonic and electronic systems WILGA 2018

    Get PDF
    WILGA annual symposium on advanced photonic and electronic systems has been organized by young scientist for young scientists since two decades. It traditionally gathers around 400 young researchers and their tutors. Ph.D students and graduates present their recent achievements during well attended oral sessions. Wilga is a very good digest of Ph.D. works carried out at technical universities in electronics and photonics, as well as information sciences throughout Poland and some neighboring countries. Publishing patronage over Wilga keep Elektronika technical journal by SEP, IJET and Proceedings of SPIE. The latter world editorial series publishes annually more than 200 papers from Wilga. Wilga 2018 was the XLII edition of this meeting. The following topical tracks were distinguished: photonics, electronics, information technologies and system research. The article is a digest of some chosen works presented during Wilga 2018 symposium. WILGA 2017 works were published in Proc. SPIE vol.10445. WILGA 2018 works were published in Proc. SPIE vol.10808

    Electrospinning of natural polymers for advanced wound care: towards responsive and adaptive dressings

    Get PDF
    In the last few years, the health-care services have registered worldwide an increased number of patients suffering from chronic wounds and ulcers, which are mainly associated with diabetes, obesity and cancer. The need for regenerating rapidly and effectively the injured skin has stimulated the research of advanced therapies for wound care. This review will discuss how biomimetic architectures produced by electrospinning natural biopolymers fulfil most of the requirements of ideal wound dressings. It will also examine the recent progress in the area of portable electrospinning systems and of multiscale instructive materials that integrate stimuli responsive and sensing elements
    corecore