Littérature scientifique sur le sujet « Hirsh model »
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Articles de revues sur le sujet "Hirsh model"
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Hirsh, Max. « Design Aesthetics of Transborder Infrastructure in the Pearl River Delta ». Journal of the Society of Architectural Historians 73, no 1 (1 mars 2014) : 137–52. http://dx.doi.org/10.1525/jsah.2014.73.1.137.
Texte intégralRésumé :
Design Aesthetics of Transborder Infrastructure in the Pearl River Delta investigates the development of a “transborder” ferry network that allows passengers in Mainland China to fly through Hong Kong International Airport without going through customs and immigration controls. Located deep inside Guangdong Province, these facilities cater to travelers whose movement across international frontiers is limited by their income or citizenship. Focusing on two of these terminals, Max Hirsh argues that the prevailing emphasis on iconic structures in the architectural history of air travel has overshadowed the emergence of distinctly un-iconic aviation facilities designed to plug less-privileged people and places into broader networks of international air travel. Hirsh locates this infrastructural innovation in the historical context of the region and interrogates its spatial logic and aesthetic composition in an effort to model a new understanding of urban space: one that illuminates an architecture of incipient global mobility that has been inconspicuously inserted into ordinary places and unspectacular structures throughout the Pearl River Delta.
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Rivers, Andrew M., et Adam Hahn. « What Cognitive Mechanisms Do People Reflect on When They Predict IAT Scores ? » Personality and Social Psychology Bulletin 45, no 6 (14 octobre 2018) : 878–92. http://dx.doi.org/10.1177/0146167218799307.
Texte intégralRésumé :
Research indicates that individuals can prospectively predict biases they will show on the implicit-association test (IAT). The present study uses the Quadruple process model to analyze data from Hahn, Judd, Hirsh, and Blair to investigate which cognitive mechanisms people reflect on when predicting their racial bias scores on the IAT. The Quadruple process model reveals that a combination of activated associations and self-regulatory control best explains what participants report when they predict their biases on the IAT. Furthermore, it appears to be specifically the total activation of positive attitudes toward Whites and negative attitudes toward minorities rather than negative attitudes toward minorities alone, that participants use to make their predictions.
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SAXTON, MATTHEW. « The Contrast Theory of negative input ». Journal of Child Language 24, no 1 (février 1997) : 139–61. http://dx.doi.org/10.1017/s030500099600298x.
Texte intégralRésumé :
Beliefs about whether or not children receive corrective input for grammatical errors depend crucially on how one defines the concept of correction. Arguably, previous conceptualizations do not provide a viable basis for empirical research (Gold, 1967; Brown & Hanlon, 1970; Hirsh-Pasek, Treiman & Schneiderman, 1984). Within the Contrast Theory of negative input, an alternative definition of negative evidence is offered, based on the idea that the unique discourse structure created in the juxtaposition of child error and adult correct form can reveal to the child the contrast, or conflict, between the two forms, and hence provide a basis for rejecting the erroneous form. A within-subjects experimental design was implemented for 36 children (mean age 5;0), in order to compare the immediate effects of negative evidence with those of positive input, on the acquisition of six novel irregular past tense forms. Children reproduced the correct irregular model more often, and persisted with fewer errors, following negative evidence rather than positive input.
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Awodutire, Phillip, Blessing Sasanya, Olohita Ufuoma et Oluwafemi Samson Balogun. « Parametric modelling of rainfall return periods in south-western Nigeria : Survival analysis approach ». F1000Research 11 (24 janvier 2022) : 83. http://dx.doi.org/10.12688/f1000research.75722.1.
Texte intégralRésumé :
Background: Rainfall is the main source of water on the earth’s surface. It infiltrates and percolates deep into the soil for groundwater recharge. Rainfall patterns, amounts, durations, and intensities can vary daily, monthly, annually, and spatially. It is therefore important to accurately estimate rainfall return periods, which can be employed in hydraulic design and flood control measures. Methods: This research considered the survival analysis approach for the prediction of rainfall return periods including intensity, and months during which these would occur in south-western Nigeria. Twenty years’ of annual rainfall data were obtained from three metrological stations and these were subjected to nine different probability plotting position methods. Results from the plotting positions was further subjected to four survival models using five years of censor time. The Akaike Information Criterion (AIC) was used to determine the best-fitting model for the dataset. Results: The Laplace probability plotting position in conjunction with the log-logistic distribution best describes the datasets, since it gave the lowest AIC value of 22.53. The log-logistic distribution is also suitable for the prediction of return period from the Weibull probability plotting position since the AIC values were 6.934 and -4.332 respectively. The Hirsh plotting position in conjunction with the Weibull distribution is also suitable for the description of the dataset. Conclusion: The established parametric models are suitable for the accurate prediction of return periods of peak rainfall events during any month of the year.
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Shen, J., et J. Hirsh. « cis-regulatory sequences responsible for alternative splicing of the Drosophila dopa decarboxylase gene ». Molecular and Cellular Biology 14, no 11 (novembre 1994) : 7385–93. http://dx.doi.org/10.1128/mcb.14.11.7385-7393.1994.
Texte intégralRésumé :
The Drosophila dopa decarboxylase gene, Ddc, is expressed in the hypoderm and in specific sets of cells in the central nervous system (CNS). The unique Ddc primary transcript is alternatively spliced in these two tissues. The Ddc CNS mRNA contains all four exons (A through D), whereas the hypodermal mRNA contains only three exons (A, C, and D). To localize cis-regulatory sequences responsible for Ddc alternative splicing, a Ddc minigene and several fusion genes containing various amounts of Ddc sequences fused to fushi tarazu (ftz) exon 1 were constructed and introduced into flies by P-element-mediated germ line transformation. We find that Ddc intron ab and exon B are sufficient to regulate Ddc alternative splicing, since transcripts of a minimal fusion gene containing most of Ddc intron ab and exon B are spliced to exon B in the CNS but not in the hypoderm. These results indicate that Ddc alternative splicing is regulated by either a negative mechanism preventing splicing to exon B in the hypoderm or a positive mechanism activating splicing to exon B in the CNS. Our previous data suggest that Ddc hypodermal splicing is the actively regulated splicing pathway (J. Shen, C. J. Beall, and J. Hirsh, Mol. Cell. Biol. 13:4549-4555, 1993). Here we show that deletion of Ddc intron ab sequences selectively disrupts hypodermal splicing specificity. These results support a model in which Ddc alternative splicing is negatively regulated by a blockage mechanism preventing splicing to exon B in the hypoderm.
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Shen, J., et J. Hirsh. « cis-regulatory sequences responsible for alternative splicing of the Drosophila dopa decarboxylase gene. » Molecular and Cellular Biology 14, no 11 (novembre 1994) : 7385–93. http://dx.doi.org/10.1128/mcb.14.11.7385.
Texte intégralRésumé :
The Drosophila dopa decarboxylase gene, Ddc, is expressed in the hypoderm and in specific sets of cells in the central nervous system (CNS). The unique Ddc primary transcript is alternatively spliced in these two tissues. The Ddc CNS mRNA contains all four exons (A through D), whereas the hypodermal mRNA contains only three exons (A, C, and D). To localize cis-regulatory sequences responsible for Ddc alternative splicing, a Ddc minigene and several fusion genes containing various amounts of Ddc sequences fused to fushi tarazu (ftz) exon 1 were constructed and introduced into flies by P-element-mediated germ line transformation. We find that Ddc intron ab and exon B are sufficient to regulate Ddc alternative splicing, since transcripts of a minimal fusion gene containing most of Ddc intron ab and exon B are spliced to exon B in the CNS but not in the hypoderm. These results indicate that Ddc alternative splicing is regulated by either a negative mechanism preventing splicing to exon B in the hypoderm or a positive mechanism activating splicing to exon B in the CNS. Our previous data suggest that Ddc hypodermal splicing is the actively regulated splicing pathway (J. Shen, C. J. Beall, and J. Hirsh, Mol. Cell. Biol. 13:4549-4555, 1993). Here we show that deletion of Ddc intron ab sequences selectively disrupts hypodermal splicing specificity. These results support a model in which Ddc alternative splicing is negatively regulated by a blockage mechanism preventing splicing to exon B in the hypoderm.
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MacKenzie, Ian A., Simon F. B. Tett et Anders V. Lindfors. « Climate Model–Simulated Diurnal Cycles in HIRS Clear-Sky Brightness Temperatures ». Journal of Climate 25, no 17 (13 avril 2012) : 5845–63. http://dx.doi.org/10.1175/jcli-d-11-00552.1.
Texte intégralRésumé :
Abstract Clear-sky brightness temperature measurements from the High-Resolution Infrared Radiation Sounder (HIRS) are simulated with two climate models via a radiative transfer code. The models are sampled along the HIRS orbit paths to derive diurnal climatologies of simulated brightness temperature analogous to an existing climatology based on HIRS observations. Simulated and observed climatologies are compared to assess model performance and the robustness of the observed climatology. Over land, there is good agreement between simulations and observations, with particularly high consistency for the tropospheric temperature channels. Diurnal cycles in the middle- and upper-tropospheric water vapor channels are weak in both simulations and observations, but the simulated diurnal brightness temperature ranges are smaller than are observed with different phase and there are also intermodel differences. Over sea, the absence of diurnal variability in the models’ sea surface temperatures causes an underestimate of the small diurnal cycles measured in the troposphere. The simulated and observed climatologies imply similar diurnal sampling biases in the HIRS record for the tropospheric temperature channels, but for the upper-tropospheric water vapor channel, differences in the contributions of the 24- and 12-hourly diurnal harmonics lead to differences in the implied bias. Comparison of diurnal cycles derived from HIRS-like and full model sampling suggests that the HIRS measurements are sufficient to fully constrain the diurnal behavior. Overall, the results suggest that recent climate models well represent the major processes driving the diurnal behavior of clear-sky brightness temperature in the HIRS channels. This encourages further studies of observed and simulated climate trends over the HIRS era.
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Hapidin, R. Sri Martini Meilanie et Eriva Syamsiatin. « Multi Perspectives on Play Based Curriculum Quality Standards in the Center Learning Model ». JPUD - Jurnal Pendidikan Usia Dini 14, no 1 (30 avril 2020) : 15–31. http://dx.doi.org/10.21009/jpud.141.02.
Texte intégralRésumé :
Playing curriculum development based on early childhood learning is a major issue in international early childhood education discussions. This study aims to look at the concepts and practices of play-based curriculum in early childhood education institutions. The study uses qualitative methods with the CIPP model program evaluation on play-based curriculum. Data collection techniqueswere carriedout using participatory observation, document studies and interviews. Participants are early childhood educators, early childhood and parents. The results found that the play-based curriculum has not yet become the main note in the preparation and development of concepts and learning practices in early childhood. Play-based curriculum quality standards have not provided a solid and clear concept foundation in placing play in the center of learning models. Other findings the institution has not been able to use the DAP (Developmentally Appropriate Practice) approach fully, and has not been able to carry out the philosophy and ways for developing a curriculum based on play. However, quite a lot of research found good practices implemented in learning centers in early childhood education institutions, such as develop children's independence programs through habituation to toilet training and fantasy play.
Keywords: Play Based Curriculum, Center Learning Model, Curriculum Quality Standards, Early Childhood Education
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Monteiro, Paulo J. M. « A note on the Hirsch model ». Cement and Concrete Research 21, no 5 (septembre 1991) : 947–50. http://dx.doi.org/10.1016/0008-8846(91)90190-s.
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Ivanov, Valery A., et Mikhail E. Zhuravlev. « Ferromagnetism in the Hubbard-Hirsch model ». Physica C : Superconductivity 185-189 (décembre 1991) : 1423–24. http://dx.doi.org/10.1016/0921-4534(91)90838-p.
Texte intégralThèses sur le sujet "Hirsh model"
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Baltes, Pascal [Verfasser], Hans [Akademischer Betreuer] Hirth, Hans [Gutachter] Hirth et Dorothea [Gutachter] Kübler. « Investment banks and underpricing : the Influence of profit sharing agreements in a two-stage IPO signalling model / Pascal Baltes ; Gutachter : Hans Hirth, Dorothea Kübler ; Betreuer : Hans Hirth ». Berlin : Technische Universität Berlin, 2018. http://d-nb.info/1169741967/34.
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Baltes, Pascal [Verfasser], Hans [Akademischer Betreuer] Hirth, Hans Gutachter] Hirth et Dorothea [Gutachter] [Kübler. « Investment banks and underpricing : the Influence of profit sharing agreements in a two-stage IPO signalling model / Pascal Baltes ; Gutachter : Hans Hirth, Dorothea Kübler ; Betreuer : Hans Hirth ». Berlin : Technische Universität Berlin, 2018. http://nbn-resolving.de/urn:nbn:de:101:1-2018102401584503123014.
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Paves, Saul. « Neo-Ortodoxia : Rabino Schimshon Raphael Hirsch e o modelo \'Torá Im Derech Eretz\' ». Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/8/8158/tde-09082016-091309/.
Texte intégralRésumé :
O objetivo principal desta dissertação é estudar a figura do Rabino Shimshon Raphael Hirsch (1808 1888), de Frankfurt, um grande mestre e líder de gerações para segmentos importantes do Judaísmo dentro do contexto histórico em que ele viveu, analisando seu impacto e legado para as futuras gerações, principalmente dentro da Ortodoxia Judaica. Esta era uma época em que a Haskalá provocava profundas mudanças na sociedade judaica, dando os primeiros passos para a criação do Movimento Reformista. Assim, entre outros objetivos deste estudo, tem destaque entender quais foram as inovações introduzidas pelo Rabino Hirsch dentro da Ortodoxia? Quais aspectos o diferenciam da Ortodoxia tradicional, transformando-o num dos principais protagonistas da Neo-Ortodoxia? Quais impactos e mudanças o novo modelo imprimiu ao sistema educacional judaico alemão e europeu? Quais as diferenças entre o modelo de Frankfurt e o modelo de Berlim, este último encabeçado pelo Rabino Azriel Hildesheimer? Outras questões analisadas dizem respeito ao modelo Torá Im Derech Eretz, que pretendia formar um sistema educacional, contemplando os estudos judaicos tradicionais e a formação secular, possibilitando aos seus seguidores uma integração plena na sociedade moderna, e se mantendo fiel às leis e normas religiosas tradicionais do Judaísmo. Quem são os herdeiros ideológicos deste movimento? Qual o legado histórico e relevância deste modelo para a sociedade judaica moderna?This dissertation aims mainly at studying the persona Rabbi Samson Raphael Hirsch (1808-1888), of Frankfurt, a great scholar and leader for different strata of Jewish society, the historical context he lived in, and analyzing his impact and legacy for generations to come, particularly regarding Jewish Orthodoxy. This was a time when Haskalah promoted profound changes in Jewish society, taking the first steps for the creation of the Reform movement. Therefore, this study also aims at understanding what the innovations introduced by Rabbi Hirsch within Orthodoxy were. What aspects differentiated between him and traditional Orthodoxy, turning him into one of the protagonists in Neo-Orthodoxy? What were the impacts and changes that his model impressed onto the German Jewish educational system and in European Jewish community? What are the differences between the model of Frankfurt and the model of Berlin, the latter headed by Rabbi Azriel Hildesheimer? Other questions raised concern the Torah Im Derech Eretz model, that intended to form an educational system covering traditional Jewish studies and secular training, enabling its followers full integration in modern society, while remaining faithful to the laws and traditional religious norms of Judaism. And, who are the ideological heirs of this movement? What is the historical legacy and relevance of this model for the modern Jewish society?
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Holzwarth, Johannes [Verfasser], et Andreas [Gutachter] Hirsch. « Development and Investigation of Model Systems for Reductive Functionalization of Carbon Nanomaterials / Johannes Holzwarth ; Gutachter : Andreas Hirsch ». Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2017. http://d-nb.info/1150964219/34.
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Herrmann, Astrid [Verfasser], et Andreas [Gutachter] Hirsch. « Synthesis of Multi-Porphyrin-Fullerene Conjugates as Models for Photosynthetic Light-Harvesting and Charge-Transfer Events / Astrid Herrmann ; Gutachter : Andreas Hirsch ». Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2017. http://d-nb.info/1140642472/34.
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Hirsch, Katja K. [Verfasser]. « Integrating structural and sedimentological observations with numerical lithospheric models to assess the 3D evolution of the South African continental passive margin / Katja K. Hirsch ». Potsdam : GFZ, 2008. http://d-nb.info/993223532/34.
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Hirsch, Katja K. [Verfasser]. « Integrating structural and sedimentological observations with numerical lithospheric models to assess the 3D evolution of the South African continental passive margin / Katja K. Hirsch ». Berlin : Freie Universität Berlin, 2009. http://d-nb.info/1023464497/34.
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Suppelna, Jan Philip [Verfasser], Stephan Tobias Florian [Gutachter] Hirsch et Daniel-Johannes [Gutachter] Tilkorn. « Kombinationstherapie des Designer-Host Defense Peptids [D]-K3H3L9 mit Doxorubicin im syngenen murinen Fibrosarkom Modell (BFS-1) zur Klärung onkolytischer Effekte / Jan Philip Suppelna ; Gutachter : Stephan Tobias Florian Hirsch, Daniel-Johannes Tilkorn ; Medizinische Fakultät ». Bochum : Ruhr-Universität Bochum, 2017. http://d-nb.info/1154307875/34.
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RICCARDI, CHIARA. « Mechanistic modeling of bituminous mortars to predict performance of asphalt mixtures containing RAP ». Doctoral thesis, 2017. http://hdl.handle.net/2158/1087507.
Texte intégralRésumé :
Nell’ultimo ventennio si è assistito a un rapido incremento dell’utilizzo di materiale fresato nelle pavimentazioni stradali dovuto in parte al risparmio economico derivante dall’utilizzo di questo materiale e in parte ai vantaggi ambientali. Tuttavia, esistono ancora due importanti problematiche alle quali non è stata data una risposta efficace: la prima riguarda la caratterizzazione del bitume invecchiato contenuto nel fresato; la seconda riguarda la possibilità di prevedere le prestazioni delle miscele confezionate utilizzando elevate quantità di fresato.
Con riferimento alla prima problematica, i metodi attualmente disponibili sono basati sull’estrazione e sul recupero del bitume contenuto nel fresato per mezzo di solventi. Tali metodi presentano però vari problemi connessi al fatto che l’estrazione e il recupero del bitume può alterarne le proprietà reologiche. Per questo motivo, nel presente lavoro, si è sviluppata una nuova procedura che permette di eseguire un retrocalcolo delle proprietà reologiche del bitume invecchiato e dei blends, composti da bitume invecchiato e bitume vergine, partendo da test su malte composte miscelando la parte fine degli aggregati del fresato e il bitume vergine; utilizzando il modello di Nielsen, appositamente adattato al caso di materiali bituminosi, e il modello di Voigt si riesce a determinare le suddette proprietà reologiche utilizzando i risultati dei test eseguiti sulle malte. Ciò ha un duplice beneficio: da una parte è possibile caratterizzare il bitume invecchiato contenuto nel fresato nelle stesse condizioni di lavoro in cui si trova all’interno della pavimentazione, evitando che subisca ulteriori trattamenti, dall’altra si possono eseguire le prove di caratterizzazione su una delle fasi che maggiormente governano le proprietà delle miscele in conglomerato bituminoso e che quindi regolano le performance delle pavimentazioni.
Con riferimento alla seconda problematica, è stata sviluppata una procedura di modellazione multiscala, basata sia su modelli reologici (2 Spring, 2 Parabolic Elements, 1 Dashpot, 2S2P1D model) sia su modelli empirici (Hirsh e Witczak models), che permette di prevedere il comportamento reologico delle miscele in conglomerato bituminoso, contenenti materiale fresato, partendo direttamente dai risultati di prove eseguite sulle malte e tenendo conto della composizione granulometrica degli aggregati e di quella volumetrica delle miscele.
La metodologia messa a punto consente di ottenere previsioni affidabili per entrambe le problematiche affrontate, come dimostrato dai risultati delle prove di validazione eseguite nell’ambito della tesi, e di fornire una soluzione innovativa ad alcune questioni che risultano attualmente di particolare rilievo ai fini della estesa utilizzazione del fresato per il confezionamento dei conglomerati bituminosi.
In last decades the use of Reclaimed Asphalt Pavement (RAP) materials in asphalt mixtures has seen a significant expansion for economical and environmental reasons. Nevertheless, there are still two important issues which have not been effectively solved: the first regards the characterization of the aged binder contained in RAP; the second concerns the ability to predict the performance of asphalt mixture composed with high RAP content.
Regarding the first problem, the current methods are based on extraction and recovery of the RAP binder using solvents; however, these methods are not fully accurate since they can alter the rheological properties of the binder. For this reason, in the present work, a new procedure to back-calculate the rheological properties of the aged binder contained in RAP materials and of the blends composed with fresh and RAP binder, was developed. This is based on DSR tests performed on mortars, composed by mixing the fine fraction of the RAP aggregate with virgin binder. Using the Nielsen model, specifically adapted to asphalt mortars’ case and the Voigt model, the rheological properties of RAP binder can be back-calculated from mortars tests. The present procedure has two advantages: the aged binder contained in RAP is tested as it is after the milling process, avoiding any further treatments, while the testing campaign is centered on the mortar phase, which is one of the most important phases governing the properties of the mixtures and, therefore, the performance of asphalt pavements.
Regarding the second problem, a multi-scale approach based on rheological model (2 Spring, 2 Parabolic Elements, 1 Dashpot, 2S2P1D model) and on empirical models (Hirsh e Witczak models) was developed to predict the rheological properties of asphalt mixture containing RAP materials, starting from tests on asphalt mortars and taking into account the grading of the aggregates and the volumetric composition of the mixtures.
This methodology allows to make reliable previsions for both the problems addressed, as demonstrated by the results of the validation tests carried out in this doctoral thesis. In addition, the present research provides innovative solutions to address some of the issues which are currently of particular importance for the purposes of extending the use of RAP material in the production of asphalt mixture.
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Hirsch, Martin [Verfasser]. « Modell-basierte Verifikation von vernetzten mechatronischen Systemen / vorgelegt von Martin Hirsch ». 2008. http://d-nb.info/991165713/34.
Texte intégralLivres sur le sujet "Hirsh model"
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Galenson, David W. Artists and the market : From Leonardo and Titian to Andy Warhol and Damien Hirst. Cambridge, Mass : National Bureau of Economic Research, 2007.
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Bollig, Ben. Moving Verses. Liverpool University Press, 2021. http://dx.doi.org/10.3828/liverpool/9781800859784.001.0001.
Texte intégralRésumé :
From Wild Tales to Zama, Argentine cinema has produced some of the most visually striking and critically lauded films of the 2000s. Argentina also boasts some of the most exciting contemporary poetry in the Spanish language. What happens when its film and poetry meet on screen? Moving Verses studies the relationship between poetry and cinema in Argentina. Although both the “poetics of cinema” and literary adaptation have become established areas of film scholarship in recent years, the diverse modes of exchange between poetry and cinema have received little critical attention. This book analyses how film and poetry transform each another, and how these two expressive media behave when placed into dialogue. Going beyond theories of adaptation, and engaging critically with concepts around intermediality and interdisciplinarity, Moving Verses offers tools and methods for studying both experimental and mainstream film from Latin America and beyond. The corpus includes some of Argentina’s most exciting and radical contemporary directors (Raúl Perrone, Gustavo Fontán) as well as established modern masters (María Luisa Bemberg, Eliseo Subiela), and seldom studied experimental projects (Narcisa Hirsch, Claudio Caldini). The critical approach draws on recent works on intermediality and “impure” cinema to sketch and assess the many and varied ways in which directors “read” poetry on screen.
Chapitres de livres sur le sujet "Hirsh model"
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Wrede, Britta, Lars Schillingmann et Katharina J. Rohlfing. « Making Use of Multi-Modal Synchrony ». Dans Theoretical and Computational Models of Word Learning, 224–40. IGI Global, 2013. http://dx.doi.org/10.4018/978-1-4666-2973-8.ch010.
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If they are to learn and interact with humans, robots need to understand actions and make use of language in social interactions. Hirsh-Pasek and Golinkoff (1996) have emphasized the use of language to learn actions when introducing the idea of acoustic packaging in human development. This idea suggests that acoustic information, typically in the form of narration, overlaps with action sequences, thereby providing infants with a bottom-up guide to attend to relevant parts and to find structure within them. The authors developed a computational model of the multimodal interplay of action and language in tutoring situations. This chapter presents the results of applying this model to multimodal parent-infant interaction data. Results are twofold and indicate that (a) infant-directed interaction is more structured than adult-directed interaction in that it contains more packages, and these packages have fewer motion segments; and (b) the synchronous structure within infant-directed packages contains redundant information making it possible to solve the reference problem when tying color adjectives to a moving object.
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Ralph, Rachel, Patrick Pennefather, Jillianne Code et Stephen Petrina. « Too Many Apps to Choose From ». Dans Research Anthology on Early Childhood Development and School Transition in the Digital Era, 277–95. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-6684-7468-6.ch014.
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Substantive research investigates the effects and impacts of tablets, in particular iPads, on children's education, but few papers discuss support for teachers in deciding which iPad applications can be integrated into the classroom. Even fewer articles are directed towards application developers. This chapter explores two standards for choosing apps for children - the four-pillar model of Hirsh-Pasek et al. (2015) and the rubric for the evaluations of educational apps for preschool children (REVEAC) by Papadakis, Kalogiannakis, and Zaranis (2017). This chapter draws from two standards for choosing iPad applications for young children in the classroom and through analysis of two applications will propose the REVEAC for educators and developers while also suggesting specific features that developers could consider when targeting children under 5 years old in educational contexts.
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Ralph, Rachel, Patrick Pennefather, Jillianne Code et Stephen Petrina. « Too Many Apps to Choose From ». Dans Mobile Learning Applications in Early Childhood Education, 20–38. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1486-3.ch002.
Texte intégralRésumé :
Substantive research investigates the effects and impacts of tablets, in particular iPads, on children's education, but few papers discuss support for teachers in deciding which iPad applications can be integrated into the classroom. Even fewer articles are directed towards application developers. This chapter explores two standards for choosing apps for children - the four-pillar model of Hirsh-Pasek et al. (2015) and the rubric for the evaluations of educational apps for preschool children (REVEAC) by Papadakis, Kalogiannakis, and Zaranis (2017). This chapter draws from two standards for choosing iPad applications for young children in the classroom and through analysis of two applications will propose the REVEAC for educators and developers while also suggesting specific features that developers could consider when targeting children under 5 years old in educational contexts.
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Becker, Richard C., et Frederick A. Spencer. « Thrombin-Directed Therapy ». Dans Fibrinolytic and Antithrombotic Therapy. Oxford University Press, 2006. http://dx.doi.org/10.1093/oso/9780195155648.003.0020.
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Anticoagulant therapy in general is designed to prevent either the generation or activity of thrombin; however, a cell-based model of coagulation provides a physiologic view of individual phases of the process, allowing more specific targets for attenuating the initiation, priming, or propagation of thrombus formation. Future categorization schemes will consider individual coagulation factors, individual sites on a given coagulation factor, and specific phases of coagulation to better identify an agent’s biochemical and physiologic activity. Unfractionated heparin (UFH) is a heterogeneous, negatively charged mucopolysaccharide consisting of approximately 18 to 50 saccharide units (molecular weight 5000–30,000 Da). Antithrombin (AT), required for the interaction (and subsequent neutralization) of UFH with thrombin and coagulation proteases including factors Xa, IXa, XIa, and XIIa, is bound by one third of administered drug (only molecules containing the critical pentasaccharide sequence can bind AT). Following IV administration, UFH binds to a variety of plasma proteins, endothelial cells, and macrophages, explaining, in part, the wide variability in anticoagulant effects for a given dose. It is cleared from the circulation through both a rapid saturable mechanism and a slower first-order mechanism. As a result, there is a dose-dependent half-life ranging from 60 minutes after a dose of 100 U/kg to 180 minutes for a dose of 400 U/kg (Beguin et al., 1988; Lam et al., 1976). Heparin-induced thrombocytopenia and hemorrhage are the most feared complications of UFH administration (see Chapter 29). Other adverse effects include osteopenia (with long-term administration). Low-molecular-weight heparin (LMWH) is prepared by the depolymerization of porcine UFH. A variety of processes are used, giving distinctive products whose molecular weights range from 4,000 to 6,500 Da (Hirsh and Levine, 1992). Like UFH, approximately one third of LMWH polysaccharide chains contain the pentasaccharide binding site for antithrombin. The LMWH–antithrombin complex (consisting of a predominance of shorter chain polysaccharides) has relatively weak antithrombin activity but retains the ability to inactivate factor Xa. The ratio of anti-Xa activity to anti-IIa (antithrombin) activity varies from 2:1 to 4:1. Similar to UFH, LMWH is not able to inhibit thrombin bound to fibrin (Weitz, 1997).
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Bachner, Andrea. « Impact Erasure ». Dans The Mark of Theory. Fordham University Press, 2017. http://dx.doi.org/10.5422/fordham/9780823277476.003.0003.
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This chapter analyzes the use of inscriptive metaphors in trauma theories, from Freud’s psychoanalytical models of the late nineteenth and early twentieth century to contemporary theorists such as Agamben, Caruth, Hirsch, and Lyotard. As an unregistered shock that continues to haunt the individual, trauma is an inscription whose impact leaves no trace. Accordingly, the inscriptive metaphors deployed in theories of trauma tend to multiply since they are caught in the dilemma of representing trauma without sacrificing a definition of trauma as the unrepresentable par excellence. For a thorough analysis of the ways in which trauma turns inscriptive, this chapter zooms in on a scandalous counterpoint: that between the number tattoos of Holocaust victims and the mark of circumcision. Whereas the number tattoo brands and produces a human body as inhuman, but can be rewritten as a corporeal memorial, circumcision can be misconstrued as traumatic mark, as a supplement to castration, but can also serve as a model for an ethical thought.
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Palaniappan, Shanthi, Sridevi U. K. et Pathur Nisha S. « Semantic Similarity Using Register Linear Question Classification (RLQC) for Question Classification ». Dans Advances in Computer and Electrical Engineering, 104–14. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1159-6.ch006.
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Question Classification(QC) mainly deals with syntactic parsing for finding the similarity. To improve the accuracy of classification, a semantic similarity approach of a question along with the question dataset is calculated. The semantic similarity of the question is initially achieved by syntactic parsing to extract the noun, verb, adverb, and adjective. However, adjectives and adverbs do give sentences an exact meaning that should also be considered for computing the semantic similarity. The proposed RLQC (Register Linear and Question Classification) model for semantic similarity of questions uses HSO (Hirst and St. Onge) measure with Gloss based measure to enhance the semantic similarity relatedness by considering the Noun, Verb, Adverb and Adjective. The semantic similarity of the question pairs for RLQC is 0.2% higher compared to HSO model. The highest semantic similarity of the proposed model achieves a better accuracy.
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« HENRY BECK HIRST, 'Edgar Allan Poe', McMakin's Model American Courier, October 1849 ». Dans Edgar Allen Poe, 329–32. Routledge, 2013. http://dx.doi.org/10.4324/9780203195475-96.
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« Prehistoric Modes of Textual Production, or, Books Begat by Other Books : Hindess and Hirst (2011) ». Dans Circling Marx : Essays 1980-2020, 236–44. BRILL, 2020. http://dx.doi.org/10.1163/9789004443976_018.
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Sacks, Jonathan. « Orthodoxy and Jewish Peoplehood ». Dans One People ?, 65–87. Liverpool University Press, 1993. http://dx.doi.org/10.3828/liverpool/9781874774006.003.0004.
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This chapter addresses the two issues, the historical and cultural dimensions of emancipation, which divided Orthodoxy. It also looks at a third dilemma of modernity, which concerns the concept of the covenantal community. What was the fate of Jewish peoplehood in modernity? On the one hand, Judaism is too deeply predicated on such an idea for it to have been jettisoned by any Orthodox thinker. On the other, the Jewish people was itself disintegrating at an alarming pace, divided into non-Orthodox readings of Judaism as religion, and secular interpretations of Judaism as a national, ethnic, cultural, or political entity. How did Orthodoxy respond to this process? On the first two issues, the great figures of Hungarian and German Orthodoxy, Rabbi Moses Sofer and Samson Raphael Hirsch, adopted different approaches. On this third issue, they took the same approach, while Orthodoxy elsewhere took other directions. The chapter also studies the English and French models of emancipation.
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Rivers, Ray. « Can Archaeological Models Always Fulfil our Prejudices ? » Dans The Connected Past. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780198748519.003.0014.
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The past few years have seen a significant growth in the use of quantitative models in archaeology. Such modelling has a long, albeit uneven, history, using ideas going back to Christaller’s (1933) use of Dirichlet/Voronoi tessellations of space in the early 20th century to construct ‘central places’. These elementary techniques for geometrizing social relations survived as late as the 1980s, most simply supplemented or replaced by other low-technology, ‘ruler and compass’ methods, such as Renfrew’s XTENT model (Renfrew 1975a, 1975b; Renfrew and Level 1979). By that time, archaeological modelling (e.g. Clarke 1968, 1977; Johnson 1977) was already incorporating the graph theory techniques of the social geographers, exemplified by the burgeoning network modelling of proximal point analysis (PPA) (e.g. Terrell 1977, 1986) and by the network-based spatial interaction models (SIMs) of the social planners and transport modellers (e.g. Wilson 1970; Wilson and Bennett 1986). However, even when adapted to historical processes (Rihll and Wilson 1987, 1991), such quantitative models were not part of the archaeological mainstream and limitations on computer power and cost meant that they had only restricted application. By the 1990s, these limitations were reinforced by a post-processual critique which led to a shift in emphasis in archaeology towards viewing space as a construct of human activity, a movement from ‘space to place’ (Hirsch 1995). Although SIMs had led this shift by downplaying the role of geography in characterizing social interactions, the dialogue about quantitative modelling turned against its reductive nature, even to the extent of shying away from mathematical analysis (e.g. Sheppard 2001). However, cheap computer power and the ready availability of commercial software packages have led to a revival in network methods. See Lock and Pouncett (2007) for an early overview, and for the current state of the art see Kandler and Steele (2012) and recent monographs edited by Bevan and Lake (2013) and Knappett (2013), as well as the other chapters in this book. The main focus of this article concerns the ‘retrodictive ability’ of archaeological models. In the absence of ‘laws’ of human behaviour, there is great freedom in how to proceed.
Actes de conférences sur le sujet "Hirsh model"
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Kim, Baik Jin, Joseph Oh et Alan Palazzolo. « Test and Theory for a Refined Structural Model of a Hirth Coupling ». Dans ASME Turbo Expo 2021 : Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/gt2021-59970.
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Abstract Hirth coupling transmits high torques in the rotating assemblies of compressors and turbines. Their mating surface contacts cause local changes in lateral shaft stiffness. This is affected by the teeth geometry, contact surface area, coupling preload, and surface finish at the contact faces. Industry practice ignores localized lateral flexibility from the Hirth coupling, or is guided by limited experience-based rules of thumb. The authors provide a novel modeling approach utilizing 3D solid finite elements which accounts for contact deformations, intricate interface teeth geometries, stress concentration, and surface finish. This provides an increased accuracy localized stiffness model for the Hirth coupling, to improve rotordynamic response predictions. Free-free natural frequencies of a test rotor including a Hirth coupling are experimentally measured. The rotor is instrumented with strain gauges for preload force measurements, and the Hirth coupling contacting surface profiles are measured with a stylus type surface profiler. A GW contact model is obtained from the measured surface profiles. An iterative computation algorithm is utilized to calculate Hirth coupling contact stiffness and contact pressure at the complex-shaped contact surfaces. Predicted and measured natural frequencies are compared vs. preload.
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Liu, Xin, Qi Yuan, Yang Liu et Jin Gao. « Analysis of the Stiffness of Hirth Couplings in Rod-Fastened Rotors Based on Experimental Modal Parameter Identification ». Dans ASME Turbo Expo 2014 : Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26448.
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Hirth couplings are widely used to transport torque between discs in turbine machinery for the advantages of precise centering, reliable positioning and excellent structural stability. However, the stiffness of the rotor segment with Hirth couplings is less than that of the integrated structure because it is weaken in the discontinuous structure. For the rotor segment with Hirth couplings, there are two types of contact status depending on the relationship between the separate stress and the compression stress. The first type is that the whole zone of Hirth couplings is in contact, where all of the Hirth couplings make contribution to the stiffness of the rotor segment. The second type of contact status is that some zones of the Hirth couplings are separated, where the equivalent stiffness of the rotor segment is only determined by the zones which are in contact. Obtaining accurate stiffness of Hirth couplings is of great significance in rotor dynamic performance analysis. In this study, the flexural stiffness of Hirth couplings of a gas turbine was calculated by three dimensional (3D) nonlinear contact Finite Element Method (FEM), and based on which the natural frequencies of a rod-fastened rotor were investigated. The stiffness modifying method which modifies the elasticity modulus of the material in the connection segment was used to conduct modal analysis in order to evaluate the effect of the stiffness weakening of the Hirth couplings. One experimental rotor with Hirth couplings and a central tie rod was designed to verify the theoretical and numerical analysis results. According to the results, the stiffness coefficient is constant when the load factor γ is less than 1.0, which means the stiffness of the Hirth couplings segment is almost constant when the pre-tightening force is large enough to keep the whole zone of the Hirth couplings in contact. The stiffness coefficient constant is about 0.32 (specific for the investigated model). And the stiffness coefficient drops dramatically when the load factor γ exceeds 1.0, which indicates that the stiffness of the Hirth couplings segment decreases dramatically since the pre-tightening force is insufficient and the Hirth couplings are separated. The Hirth couplings segment stiffness obtained by experimental modal parameter identification turned out to be consistent with the calculated results by FEM. The modified stiffness of the Hirth couplings segment were applied on the dynamic performance analysis of a real gas turbine rotor and the accuracy of calculating results was improved.
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Druta, Cristian, Linbing Wang, George Z. Voyiadjis et Chris Abadie. « Estimation of the Stiffness of Asphalt Mastics Using Hirsch Model ». Dans Geo-Denver 2007. Reston, VA : American Society of Civil Engineers, 2007. http://dx.doi.org/10.1061/40924(308)4.
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Liu, Yang, Qi Yuan et Zuo Zhou. « Contact Status Analysis of Rod-Fastened Rotors With Hirth Coupling in Gas Turbines ». Dans ASME Turbo Expo 2015 : Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-42816.
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The aim of this paper is to provide some basis for the design and assembly of a rod-fastened rotor with Hirth coupling. The rod-fastened rotor is comprised of a series of discs clamped together by a central tie rod or several tie rods on the pitch circle diameter. The key difference between a rod-fastened rotor and an integrated one is the existence of contact interfaces. The contact status of contact interface in the rod-fastened rotor is the key concern for accurate rotor dynamic analysis. Therefore, the method of accurately describing the slippage status and contact status is presented in this paper. The approach of eliminating the slippage and making the radial contact pressure distribution more uniform is also presented. According to the characteristics of Hirth coupling, one model of a turbine end rotor with Hirth coupling of a heavy duty gas turbine was built. The three-dimensional finite element contact method and non-linear behaviors such as friction were also taken into account. The effect of pre-tightening forces, centrifugal forces and overhung rim lengths on the radial slippage including initial radial slippage usi and dynamic radial slippage usd of contact interface was determined. A dimensionless coefficient cr was also defined to describe the radial contact pressure distribution of contact interface which was influenced by the values of pre-tightening forces, centrifugal forces and wheel rim lengths respectively. The results of Hirth coupling indicate that the initial radial slippage increases with the pre-tightening forces, and for a fixed pre-tightening force, usi decreased with the increase of overhung rim length. In addition, there is an optimum rim length to eliminate the dynamic radial slippage usd produced by the change of the centrifugal force. Through the analysis of contact pressure distribution, we know that the reasonable design of the load relief trough processed in the overhung rim makes the contact pressure distribution more uniform. Finally, the effect of temperature load on the radial slippage and contact pressure distribution was investigated.
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Poirson, Allen, et Albert Ahumada. « Model for space-varying cone placement in the fovea ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.wg52.
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We present a model for the placement of cones in the fovea which is an extension of the model for the near foveolar region presented by Ahumada and Poirson (ARVO 1986). This model has three parameters which can vary with eccentricity: (1) the radius of the cone disk, (2) the ratio of the cone disk standard deviation to the mean radius, (3) the standard deviation of the postpacking jitter addition. The physiological data modeled are the positions of the inner cone segments of the cone mosaic from an adult primate presented by Hirsch and Miller (ARVO 1985). This model correctly tracks the decrease in cone density as eccentricity increases by simply increasing the cone radius with distance. The increase in variance of cone positions in the data, as measured by two descriptive statistics, is consistent with the predictions of the model with the second two parameters constant.
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Qin, Zhenpeng, et John C. Bischof. « One Dimensional Experimental Setup to Study the Heating of Nanoparticle Laden Systems ». Dans ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19676.
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Intensive efforts have been put into the use of gold nanoparticles (GNPs) for the enhancement of hyperthermia using laser in recent years since the groundbreaking work of Hirsh et al.(1) using gold nanoshells (GNS). Both in vitro (2), and in vivo (3) studies show promising results. For example, GNS, a special kind of GNP, are being manufactured and are in clinical trials (Nanospectra Bioscience, Inc). While the data is compelling, unfortunately the fundamentals of GNP heating are not entirely understood. For example, there are large discrepancies in the experimentally measured photothermal efficiency of GNPs (4, 5). Furthermore, lumped models of GNP heating in solution, by using small volume of GNP solution (4, 5), or stirring the solution (6), neglecting the variation of heat absorption throughout a system require improvement. In reality, the GNPs will attenuate the laser beam as it passes through the GNP host medium. GNPs at different locations will absorb different amount of laser energy and hence have different heat generation.
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Janssen, Manfred J., et John S. Joyce. « 35-Year Old Splined-Disc Rotor Design for Large Gas Turbines ». Dans ASME 1996 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-gt-523.
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The design principles of the splined-disc-type rotor with Hirth-serration couplings used in all Siemens heavy-duty gas turbines since 1960 are explained. The benefits of this rotor construction are elaborated against the operational requirements imposed on rotors by present-day large advanced gas turbines for electric power generation. Details of the stress assessment, analysis and testing underlying the design, as well as a description of the assembly of the rotor are also presented, using mostly the 170 MW-class 3600 rpm Model V84.3A gas turbine to illustrate the most recent technology.
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Dunham, John. « A New Endwall Model for Axial Compressor Throughflow Calculations ». Dans ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-075.
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It is well recognised that the endwall regions of a compressor — in which the annulus wall flow interacts with the mainstream flow — have a major influence on its efficiency and surge margin. Despite many attempts over the years to predict the very complex flow patterns in the endwall regions, current compressor design methods still rely largely on empirical estimates of the aerodynamic losses and flow angle deviations in these regions. This paper describes a new phenomenological model of the key endwall flow phenomena treated in a circumferentially-averaged way. It starts from Hirsch and de Ruyck’s annulus wall boundary layer approach, but makes some important changes. The secondary vorticities arising from passage secondary flows and from tip clearance flows are calculated. Then the radial interchanges of momentum, energy and entropy arising from both diffusion and convection are estimated The model is incorporated into a streamline curvature program. The empirical blade force defect terms in the boundary layers are selected from cascade data. The effectiveness of the method is illustrated by comparing the predictions with experimental results on both low speed and high speed multistage compressors. It is found that the radial variation of flow parameters is quite well predicted, and so is the overall performance, except when significant endwall stall occurs.
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Brunetie`re, Noe¨l. « A Modified Turbulence Model for Low Reynolds Numbers : Applications to Hydrostatic Seals ». Dans ASME/STLE 2004 International Joint Tribology Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/trib2004-64026.
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The order of magnitude of the Reynolds number in thin lubricant films varies between 102 and 105. For Reynolds numbers higher than 103, the fluid flow becomes turbulent. It is well accepted in lubrication to use a zero equation turbulence model of the type developed by Constantinescu [1] or Elrod, Ng and Pan [2–4] or Hirs [5]. The Elrod and Ng approach is certainly the most efficient for combined pressure and shear flows where the Reynolds number is above 104. This paper proposes a modification of the Elrod and Ng model in order to ensure a good correlation with experimental data obtained with low Reynolds number turbulent flows. The present model, coupled with a scaling factor for taking into account the transition to turbulence, is therefore accurate for all the typical Reynolds number values recorded in lubrication. The model is then applied to hydrostatic noncontacting face seals, which usually operate at Reynolds numbers varying from 103 to 104. The accuracy of the model is shown for this particular application of radial rotating flow. A special study is made of the transition to turbulence. The results are compared with those obtained using the initial Elrod and Ng model. The axial stiffness coefficient and the stability threshold are significantly affected by the turbulence model.
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Rimpel, Aaron M., et Matthew Leopard. « Simple Contact Stiffness Model Validation for Tie Bolt Rotor Design With Butt Joints and Pilot Fits ». Dans ASME Turbo Expo 2019 : Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-90396.
Texte intégralRésumé :
Abstract Tie bolt rotors for centrifugal compressors comprise multiple shaft components that are held together by a single tie bolt. The axial connections of these rotors — including butt joints, Hirth couplings, and Curvic couplings — exhibit a contact stiffness effect, which tends to lower the shaft bending frequencies compared to geometrically identical monolithic shafts. If not accounted for in the design stage, shaft bending critical speed margins can be compromised after a rotor is built. A previous paper had investigated the effect of tie bolt force on the bending stiffness of stacked rotor assemblies with butt joint interfaces, both with and without pilot fits. This previous work derived an empirical contact stiffness model and developed a practical finite element modeling approach for simulating the axial contact surfaces, which was validated by predicting natural frequencies for several test rotor configurations. The present work built on these previous results by implementing the same contact stiffness modeling approach on a real tie bolt rotor system designed for a high pressure centrifugal compressor application. Each joint location included two axial contact faces, with contact pressures up to five times higher than previously modeled, and a locating pilot fit. The free-free natural frequencies for different amounts of tie bolt preload force were measured, and the frequencies exhibited the expected stiffening behavior with increasing preload. However, a discontinuity in the data trend indicated a step-change increase in the contact stiffness. It was shown that this was likely due to one or more of the contact faces becoming fully engaged only after sufficient tie bolt force was applied. Finally, a design calculation was presented that can be used to estimate whether contact stiffness effects may be ignored, which could simplify rotor analyses if adequate contact pressure is used.