262,416 research outputs found
Impulse-driven surface breakdown data : a Weibull statistical analysis
No full textSurface breakdown of oil-immersed solids chosen to insulate high-voltage, pulsed-power systems is a problem that can lead to catastrophic failure. Statistical analysis of the breakdown voltages, or times, associated with such liquid-solid interfaces can reveal useful information to aid system designers in the selection of solid materials. Described in this paper are the results of a Weibull statistical analysis, applied to both breakdown-voltage data and time-to-breakdown data generated in gaps consisting of five different solid polymers immersed in mineral oil. Values of the location parameter γ provide an estimate of the applied voltage below which breakdown will not occur, and under uniform-field conditions, γ varied from 192 kV (480 kV/cm) for polypropylene to zero for ultra-high molecular weight polyethylene. Longer times to breakdown were measured for UHMWPE when compared with the other materials. However, high values of the shape parameter β reported in the present paper suggest greater sensitivity to an increase in applied voltage – that is, the probability of breakdown increases more sharply with increasing applied voltage for UHMWPE compared to the other materials. Analysing peak-applied-voltage data, only PP consistently reflected a low value of β across the different sets of test conditions. In general, longer mean times to breakdown were found for solid materials of εr more closely matched to that of the surrounding mineral oi
Optimisation of the spark gap parameters for high powered ultrasound applications
No full textThere is considerable interest in the industrial and commercial applications of high power ultrasound (HPU) generated using pulsed power techniques. These applications include metal peening, the treatment of ores and minerals before extraction, drilling technologies and the comminution and recovery of waste materials. In all of these applications, it is important to optimise the parameters of the discharge causing the shock wave in the working medium to maximise the efficiency of the treatment. In a research project at the University of Strathclyde, some applications of HPU to the treatment of waste to assist in recycling have been investigated. Two systems have been considered, slag from the manufacture of stainless steel and bottle glass. With the slag material, it is intended to separate stainless steel from the silicate matrix to permit its recovery. With the bottle glass, the intention is comminution of the material to allow it to be recycled in a more valuable form. Measurements of the efficiency of these processes have been made in terms of the mass of material processed versus the energy input as the parameters of the discharge gap have been varied. In parallel with this work, measurements have been made using pinducer sensors to determine the energy in HPU pulses generated by discharges under identical conditions. Correlations are made between the efficiency of material treatment and the intensity of the HPU pulse measured in the far field. It is hoped that this approach will allow the optimal gap parameters to be determined using pinducer measurements rather than time consuming trials based around materials processing
Superposition of DC voltage and submicrosecond impulses for energization of electrostatic precipitators
No full textThis paper discusses the development of an impulsive microelectrostatic precipitation technology, which uses superposition of submicrosecond high-field pulses and dc electric field. Short impulses allow the application of higher voltages to the ionization electrodes of a precipitation system without the initiation of breakdown. These higher levels of electric field generate higher ionic concentrations, resulting in more efficient charging of the airborne particles, and can potentially improve precipitation efficiency. This work is focused on the analysis of the behavior of impulsive positive corona discharges in a coaxial reactor designed for precipitation studies. The efficiency of precipitation of coarse and fine particles has been investigated using different dc and impulse voltage levels in order to establish optimal energization modes
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Protecting Animals 36: Author Witi Ihimaera
No full textIn this very special episode of Knowing Animals I am joined by beloved New Zealand author Witi Ihimaera. Witi has written many books featuring nonhuman animals. He offers us a non-colonial lens through which to think about the human/nonhuman relationship
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
The triggered behavior of a controlled corona stabilised cascade switch
No full textCorona stabilised switches have been shown to have advantages in pulse power switching applications due to their high repetition rates and low jitter. Work performed in recent years by the High Voltage Technologies Group within the Department of Electronic and Electrical Engineering at the University of Strathclyde has shown that the operating voltage range of such switches can be extended by using a multi-gap cascade configuration. One particular multi-gap topology was shown to operate under pressure at 100 kV with a switching jitter of 2ns. It has since been shown that by modifying the topology of the corona sources on the electrodes, it is possible to control the grading of the voltage distribution across the gaps in the cascade. The voltages across each gap and the self-break behaviour of the cascade were found to be in close agreement with the values predicted from the corona emission characteristics for the tested electrode topologies. This paper reports on a further examination of the behaviour of the corona controlled switching topology, where triggered operation of the switch has been investigated for different voltage distributions across the cascade gaps
Author in Essay by I. A. Goncharov “Pepiniere”
No full textFeatures of the embodiment of the author’s position in the essay by I. A. Goncharov “Pepiniere” are considered. The relevance of the study is due to the poorly studied poetics of this work. A review of the scientific literature on relevant topics is performed. Methodological and theoretical definitions are given. The scientific novelty of the article is in the fact that for the first time attention is paid to artistic techniques that allow to identify the author's position in the specified literary text. The author of the article grounds her opinion from the fact that, despite the dominance of the subjective point of view, other characters’ views stand out in the work. It is concluded in the study that the text of the work represents a biographical author and author-creator. It was established that the position of the author-creator is expressed through the title, epigraphs, which are quotes, as well as through different points of view, including the author-character, the author-narrator, the characters of the work. The author of the article dwells in detail on different ways of expressing the points of view of the author-character and the author-narrator. It is proved that the point of view of the author-character and the author-narrator can intersect, they are interchanged. The author's development of the term comic “point of view” is presented in the article
Espai i identitat en l'obra de Jordi Pere Cerdà. Una geografia literària cerdaniana
No full textL'obra de l'autor nord-català Jordi Pere Cerdà (1920-2011) teixeix una cartografia literària que abasta tota dimensió espacial -real, imaginada i ficcional. Les prospeccions que assagen els seus texts es fonen en el medi natural i rural, canten a l'amor, als veïns i als éssers fantàstics del folklore català, es comprometen amb els refugiats encarant-se a tota frontera i, també, a tot abisme interior i exterior que oprimesca l'ésser. El mapatge cognitiu i literari que crea Cerdà sobrepassa qualsevol obstacle per construir espais oberts i possibles, en comunió amb l'altre. Partint d'una aproximació teòrica geocrítica, aquest treball d'investigació aprofundeix en diverses nocions sobre l'espacialitat lligades a un context convuls, ple de transformacions a nivell socioeconòmic, polític, cultural i lingüístic, el qual determinarà la vida d'un autor i d'un territori transfronterer com el de la Cerdanya i la Catalunya del Nord. En definitiva, la rica experiència vital de Jordi Pere Cerdà ens permet reflexionar sobre les relacions que vulguem establir entre els individus i amb el nostre hàbitat natural i cultural, a fi d'esdevenir membres actius que participen de la transformació dels espais que configuren les nostres identitats.The work of the North Catalan author Jordi Pere Cerdà (1920-2011) weaves a literary cartography which reaches all spatial dimensions -real, imagined and fictional. The prospections proved by their texts merge with the natural and rural environment, sing to love, neighbours and the fantastic beings of the Catalan folklore. Such prospections also commit themselves with the refugees facing every frontier and, also, facing all interior and exterior abyss that oppresses the being. The cognitive and literary mapping created by Cerdà overcomes any obstacle to construct opened and possible spaces, in communion with the other. Based on the theoretical approach called geocriticism, this research study delves into various notions about spatiality linked to a convulsive context, full of transformations at a socioeconomic, political, cultural and linguistic level; these transformations will determine the life of an author and a cross-border territory such as Cerdagne and Northern Catalonia. In short, the rich experience of Jordi Pere Cerdà allows us to reflect on the relationships we want to establish between individuals, as well as between human groups and our natural and cultural habitat, in order to become active members that participate in the transformation of the spaces that make up our identities.Programa de Doctorat en Llengües Aplicades, Literatura i Traducci
Els llibres d'il·lustració infantil i juvenil en l'Educació Artística. Un cas concret a partir de l’autora Olga de Dios
No full textTreball Final de Grau en Mestre o Mestra d'Educació Primària (Pla de 2018). Codi: MP1840. Curs acadèmic: 2021/2022El treball de fi de grau que aneu a veure a continuació, és un projecte que consisteix en com es poden
treballar a les aules de primària els llibres de l’autora i il·lustradora Olga de Dios. Tractant de treballar
el llibre com a objecte artístic a nivell elemental. A més, de presentar a l’autora i il·lustradora, donarla a conèixer i veure els valors que transmet, també llegiríem quatre de les seues obres a l’aula com
són: “Leotolda”, “En familia”, “Rana de Tres Ojos”, i “Pájaro Amarillo”. Tot açò sumat a la
realització d’un quadern de classe on es colorejaria alguns dels seus personatges de les obres seguint
pautes a nivell curricular. Realitzaríem també una eixida a la biblioteca municipal, on a banda de
rebre una educació no formal, ens facilitaria una mica el fet d’endinsar-nos al món de la il·lustració
infantil, on allí dins, el professional encarregat ens guiarà pels llibres que hi haurà a la biblioteca. I,
per a concloure, elaboraríem un llibre creat per l’alumnat on seguint unes pautes establertes per Olga
de Dios al seu llibre “Leotolda” buscaríem fer una retroalimentació intentant contactar amb ella.
D’aquesta manera tancaríem el cicle que vam començar donant-la a conèixer com a escriptora i
il·lustradora, i exploraríem on està el límit de la creativitat del propi alumnat.The final degree project you are going to see below is a project that looks at how books by author and
illustrator Olga de Dios can be worked on in primary school classrooms. Considering the book as an
artistic object at an elementary level. Besides presenting the author and illustrator, introducing her,
and seeing the values she transmits, we would also read four of her works in the classroom, such as:
"Leotolda”, "In the family", "Three-Eyed Frog", and "Yellow Bird.". All this, in addition to the
creation of a class notebook in which some of his characters from her work would be colored
following guidelines at the curricular level. We would also go out to the local library, where in
addition to receiving a non-formal education, it would make it a little easier for us to enter the world
of children's illustration, where inside, the professional in charge will guide us through the books
which will be in the library. And, to conclude, we would make a book created by the students, where
following some guidelines established by Olga de Dios in her book "Leotolda" we would look for
feedback by trying to contact her. In this way, we would close the cycle that we started by presenting
her as an author and illustrator, and we would explore where the limit of creativity of the students
themselves is
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