Articles de revues : « Ecai »

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K. Ronoh, Peter, Fred N. Keraro et Samuel W. Wachanga. « Enhancing Biology Achievement of Secondary School Learners Using Experiential Computer Assisted Instruction ». International Education Studies and Sustainability 1, n^o 1 (27 février 2021) : p58. http://dx.doi.org/10.22158/iess.v1n1p58.

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This paper reports a study that investigated effects of Experiential Computer Assisted Learning (ECAI) on learners’ achievement in Biology in Kenya. Solomon’s Non-Equivalent group four research design was used. Four schools were purposively sampled. The schools were randomly assigned to four groups, two experimental and two control groups. All the learners covered same content. Teachers of the experimental groups used ECAI while teachers of control groups used regular approaches. The study focused on the topic Genetics and involved a sample of 163 Form Four learners. Biology Achievement Test (BAT) was used to collect data. The instrument was validated by five experts in Educational Research. Reliability of BAT was estimated using Cronbach’s alpha coefficient. A co-efficient of 0.719 was obtained. The Constructivist and Experiential learning theories guided the study. Data collected were analyzed using ANOVA, t-test and ANCOVA. Hypotheses were tested at an alpha level of 0.05. The findings indicate that learners taught using ECAI had significantly higher scores than those in control groups. It is recommended that the Kenya Institute of Curriculum Development (KICD) incorporates ECAI in the teaching of school Biology to enhance learning. Science teacher education programmes should also incorporate ECAI to enhance its use in schools.

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Ronoh, Peter K., Fred N. Keraro et Samuel W. Wachanga. « Enhancing Biology Achievement of Secondary School Learners Using Experiential Computer Assisted Instruction ». International Education Studies and Sustainability 1, n^o 1 (27 février 2021) : p59. http://dx.doi.org/10.22158/iess.v1n1p59.

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This paper reports a study that investigated effects of Experiential Computer Assisted Learning (ECAI) on learners’ achievement in Biology in Kenya. Solomon’s Non-Equivalent group four research design was used. Four schools were purposively sampled. The schools were randomly assigned to four groups, two experimental and two control groups. All the learners covered same content. Teachers of the experimental groups used ECAI while teachers of control groups used regular approaches. The study focused on the topic Genetics and involved a sample of 163 Form Four learners. Biology Achievement Test (BAT) was used to collect data. The instrument was validated by five experts in Educational Research. Reliability of BAT was estimated using Cronbach’s alpha coefficient. A co-efficient of 0.719 was obtained. The Constructivist and Experiential learning theories guided the study. Data collected were analyzed using ANOVA, t-test and ANCOVA. Hypotheses were tested at an alpha level of 0.05. The findings indicate that learners taught using ECAI had significantly higher scores than those in control groups. It is recommended that the Kenya Institute of Curriculum Development (KICD) incorporates ECAI in the teaching of school Biology to enhance learning. Science teacher education programmes should also incorporate ECAI to enhance its use in schools.

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Sandberg, Jacobijn. « ECAI '90 : The Invited Speakers ». AI Communications 3, n^o 3 (1990) : 143–52. http://dx.doi.org/10.3233/aic-1990-3306.

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Sandberg, Jacobijn. « ECAI '90 : The Invited Speakers ». AI Communications 3, n^o 4 (1990) : 184–86. http://dx.doi.org/10.3233/aic-1990-3403.

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Walsh, Toby. « ECAI'92 : A Methodological Malaise ? » AI Communications 6, n^o 1 (1993) : 59–61. http://dx.doi.org/10.3233/aic-1993-6105.

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Winands, Mark, et Tristan Cazenave. « ECAI Computer Games Workshop 2014 ». ICGA Journal 37, n^o 4 (1 décembre 2014) : 230–31. http://dx.doi.org/10.3233/icg-2014-37409.

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Anzil, Verónica. « Representaciones en torno a las entidades colaboradoras de la adopción internacional (ECAI) en la prensa. » Arxiu d'Etnografia de Catalunya, n^o 12 (15 novembre 2012) : 151. http://dx.doi.org/10.17345/aec12.151-172.

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Entre 1997 y 2010 llegaron a Cataluña 11.459 niños y niñas nacidos y adoptados en el extranjero, que ahora forman parte de familias locales. En la gran mayoría de esos procesos de adopción participó alguna de las Entidades Colaboradoras de la Adopción Internacional (ECAI) acreditadas en la comunidad autónoma. Las ECAI son asociaciones sin ánimo de lucro que realizan funciones de mediación entre los solicitantes de adopción y los países de origen del menor. Teniendo en cuenta que los medios de comunicación son una forma de construcción social de la realidad, y con el objetivo de reconstruir las representaciones (re)creadas por la prensa sobre las ECAI, realicé un análisis de los 780 artículos periodísticos aparecidos entre 1997 y 2010 en dos de los periódicos de mayor tirada en Cataluña. Analicé, además, las actas de la Comisión especial sobre adopción internacional del Senado, con fines comparativos.

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Winands, Mark, et Tristan Cazenave. « Computer Games Workshop at ECAI 2012 ». ICGA Journal 35, n^o 3 (1 septembre 2012) : 188–89. http://dx.doi.org/10.3233/icg-2012-35309.

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SZILAK, Laszlo, Andras DER, Ferenc DEAK et Pal VENETIANER. « Kinetic characterization of the EcaI methyltransferase ». European Journal of Biochemistry 218, n^o 2 (décembre 1993) : 727–33. http://dx.doi.org/10.1111/j.1432-1033.1993.tb18427.x.

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Fensel, Dieter. « ECAl'94 Workshop on Formal Specification Methods for Knowledge-bassed Systems ». Knowledge Engineering Review 9, n^o 4 (décembre 1994) : 417–20. http://dx.doi.org/10.1017/s026988890000713x.

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The Workshop on Formal Specification Methods for Knowledge-based Systems (KBS) took place in Amsterdam on August 8 1994 as part of the workshop program of the 11th European Conference on Artificial Intelligence (ECAI'94). It was the sixth workshop in a series concerned with the development and application of formal and executable specification languages for KBSs. Starting from the first familiarization workshop at GMD in Bonn 1992, where the different research groups met for the first time, further successor workshops were held at the University of Karlsruhe, the University of Amsterdam, and again at GMD in Bonn. Additionally, at ECAI'92 in Vienna, a workshop was held to compare different specification approaches for complex multi-layered KBSs.

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de Màntaras, Ramon Lopéz. « ECAI'90 : Summary Speech on Knowledge Engineering ». AI Communications 4, n^o 1 (1991) : 26–29. http://dx.doi.org/10.3233/aic-1991-4105.

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Ruttkay, Zs. « ECAI'94 : Report on the Constraint Processing Workshop ». AI Communications 8, n^o 1 (1995) : 36–37. http://dx.doi.org/10.3233/aic-1995-8104.

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Blundell, David, et Jeanette Zerneke. « Early Austronesian Historical Voyaging in Monsoon Asia : Heritage and Knowledge for Museum Displays Utilizing Texts, Archaeology, Digital Interactive Components, and GIS Approaches ». International Journal of Humanities and Arts Computing 8, supplement (mars 2014) : 237–52. http://dx.doi.org/10.3366/ijhac.2014.0110.

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This paper covers work using historical geographic information systems (GIS) by the Electronic Cultural Atlas Initiative (ECAI) 2 to trace early navigation in Monsoon Asia. To open a scholarly Web-based platform to a broader audience, the ECAI Austronesia Team is collaborating with the Maritime Buddhism project conceived by Lewis Lancaster. The Maritime Buddhism project is being developed to reach general audiences with a high level of interactivity and 3D visualizations featuring historic timelines, ships, trade routes and trade winds, travelling monks, life at ports, and stories. To allow the information to be more accessible, mobile phone apps and multi-media museum displays are being developed. Austronesian speaking peoples made navigation a way of life across the Indian and Pacific oceans spanning thousands of years. The goal of this integration of content and technology is to enable our understanding of Monsoon Asia, its diffusion of culture, and oceanic navigation to become alive and accessible.

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Edelkamp, Stefan, et Roman Bartak. « Preface ». Proceedings of the International Symposium on Combinatorial Search 5, n^o 1 (1 septembre 2021) : xi—xii. http://dx.doi.org/10.1609/socs.v5i1.18309.

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This volume contains papers accepted for presentation at SoCS 2014, the Seventh Annual Symposium on Combinatorial Search, held in Prague, Czech Republic, on August 15-17, 2014. SoCS 2014 was held in cooperation with AAAI and collocated with the European Conference on Artificial Intelligence (ECAI 2014.

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Hill, Patricia M., Bogdan Filipic et Nick Jennings. « ECAI'92 – The 10th European Conference on Artificial Intelligence ». AI Communications 5, n^o 4 (1992) : 205–7. http://dx.doi.org/10.3233/aic-1992-5407.

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Silva, José Francisco Pezzi da. « Two new species of Bryconamericus Eigenmann (Characiformes : Characidae) from southern Brazil ». Neotropical Ichthyology 2, n^o 2 (juin 2004) : 55–60. http://dx.doi.org/10.1590/s1679-62252004000200002.

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Two new species of Bryconamericus are described from southern Brazil: B. patriciae, from the headwaters of rio Pelotas (rio Uruguay drainage) and rio das Antas (laguna dos Patos drainage) and B. ecai from lower rio Taquari drainage. Bryconamericus patriciae differs from other Bryconamericus species from southern South America, by the following combination of characters: body depth (25.5-30.3% SL); head length (25.2-27.6% SL); pelvic-fin length (11.0-14.4% SL); branched anal-fin rays 14-18; teeth of outer row of premaxilla regularly implanted; teeth of inner row of premaxilla pentacuspid; teeth compressed distally; and males with bony hooks on pelvic and anal fins. Bryconamericus ecai differs from other Bryconamericus species from southern South America by the following combination of characters: body depth (33.1-36.9% SL); eye diameter (31.1-33.9% HL); snout length (26.8-32.4% HL); branched anal-fin rays 15-18; teeth of outer row of premaxilla regularly implanted; teeth of inner row of premaxilla tricuspid or pentacuspid; teeth compressed distally; and males with bony hooks on pelvic and anal fins.

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Preece, Alun D. « Validation of knowledge-based systems : Current trends and issues ». Knowledge Engineering Review 10, n^o 1 (mars 1995) : 69–71. http://dx.doi.org/10.1017/s0269888900007281.

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Assuring the reliability of knowledge-based systems has become an important issue in the development of the knowledge engineering discipline. There has been a workshop devoted to these topics at most of the major AI conferences (IJCAI, AAAI and ECAI) for the last five years, and the 1994 European Conference on Artificial Intelligence (ECAI-94) in Amsterdam was no exception. The focus of the meeting was on validation techniques for KBS, where validation is defined as the process of determining if a KBS meets its users' requirements; implicitly, validation includes verification, which is the process of determining if a KBS has been constructed to comply with certain formally-specified properties, such as consistency and irredundancy. The Amsterdam workshop was an intimate meeting, and the fifteen attendees were predominantly from European institutions. In spite of—or perhaps because of—this intimacy, the workshop succeeded in highlighting many of the significant trends and issues within its area of concern. The purpose of this short article is to review the trends and issues in question, drawing upon the contributions made during the workshop.

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Gmel, Annik Imogen, Thomas Druml, Rudolf von Niederhäusern, Tosso Leeb et Markus Neuditschko. « Genome-Wide Association Studies Based on Equine Joint Angle Measurements Reveal New QTL Affecting the Conformation of Horses ». Genes 10, n^o 5 (14 mai 2019) : 370. http://dx.doi.org/10.3390/genes10050370.

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The evaluation of conformation traits is an important part of selection for breeding stallions and mares. Some of these judged conformation traits involve joint angles that are associated with performance, health, and longevity. To improve our understanding of the genetic background of joint angles in horses, we have objectively measured the angles of the poll, elbow, carpal, fetlock (front and hind), hip, stifle, and hock joints based on one photograph of each of the 300 Franches-Montagnes (FM) and 224 Lipizzan (LIP) horses. After quality control, genome-wide association studies (GWASs) for these traits were performed on 495 horses, using 374,070 genome-wide single nucleotide polymorphisms (SNPs) in a mixed-effect model. We identified two significant quantitative trait loci (QTL) for the poll angle on ECA28 (p = 1.36 × 10−7), 50 kb downstream of the ALX1 gene, involved in cranial morphology, and for the elbow joint on ECA29 (p = 1.69 × 10−7), 49 kb downstream of the RSU1 gene, and 75 kb upstream of the PTER gene. Both genes are associated with bone mineral density in humans. Furthermore, we identified other suggestive QTL associated with the stifle joint on ECA8 (p = 3.10 × 10−7); the poll on ECA1 (p = 6.83 × 10−7); the fetlock joint of the hind limb on ECA27 (p = 5.42 × 10−7); and the carpal joint angle on ECA3 (p = 6.24 × 10−7), ECA4 (p = 6.07 × 10−7), and ECA7 (p = 8.83 × 10−7). The application of angular measurements in genetic studies may increase our understanding of the underlying genetic effects of important traits in equine breeding.

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Petridou, E. T., et E. Germeni. « The European Code Against Injuries (ECAI) : translating evidence into practice ». Injury Prevention 14, n^o 5 (1 octobre 2008) : 282–83. http://dx.doi.org/10.1136/ip.2008.020073.

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Flach, P. « Conferences. Abductive and inductive reasoning : report of the ECAI'96 workshop ». Logic Journal of IGPL 5, n^o 5 (1 septembre 1997) : 773–78. http://dx.doi.org/10.1093/jigpal/5.5.773.

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Widmer, Gerhard. « Report on the ECAI workshop on artificial intelligence and music, held during the 9th European conference on artificial intelligence (ECAI‐90), Stockholm, Sweden, August 6–10, 1990 ». Interface 19, n^o 4 (janvier 1990) : 293–96. http://dx.doi.org/10.1080/09298219008570572.

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Fox, Maria, et Luc De Raedt. « Introduction to the Special Issue on the ECAI 2012 Turing and Anniversary Track ». AI Communications 27, n^o 1 (2014) : 1. http://dx.doi.org/10.3233/aic-130577.

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ROUSSET, MARIE-CHRISTINE, et SUSAN CRAW. « ECAI-96 workshop on validation, verification and refinement of KBS : A short report ». Knowledge Engineering Review 12, n^o 01 (janvier 1997) : 95–98. http://dx.doi.org/10.1017/s0269888997000052.

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Ensuring reliability and enhancing quality of Knowledge Based Systems (KBS) are critical factors for their successful deployment in real-world applications. This is a broad task involving both methodological and formal approaches for designing rigorous Validation, Verification and Testing (VVT) methods and tools. Some of these can be adapted from conventional software engineering, while others rely on specific aspects of KBS.

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Puigbò, Pere, Ignacio G. Bravo et Santiago Garcia-Vallvé. « E-CAI : a novel server to estimate an expected value of Codon Adaptation Index (eCAI) ». BMC Bioinformatics 9, n^o 1 (2008) : 65. http://dx.doi.org/10.1186/1471-2105-9-65.

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KORNAI, ANDRÁS. « Extended finite state models of language ». Natural Language Engineering 2, n^o 4 (décembre 1996) : 287–90. http://dx.doi.org/10.1017/s1351324997001526.

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In spite of the wide availability of more powerful (context free, mildly context sensitive, and even Turing-equivalent) formalisms, the bulk of the applied work on language and sublanguage modeling, especially for the purposes of recognition and topic search, is still performed by various finite state methods. In fact, the use of such methods in research labs as well as in applied work actually increased in the past five years. To bring together those developing and using extended finite state methods to text analysis, speech/OCR language modeling, and related CL and NLP tasks with those in AI and CS interested in analyzing and possibly extending the domain of finite state algorithms, a workshop was held in August 1996 in Budapest as part of the European Conference on Artificial Intelligence (ECAI'96).

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Skujina, Ilze, Clare L. Winton, Matthew J. Hegarty, Robert McMahon, Deborah M. Nash, Mina C. G. Davies Morel et Neil R. McEwan. « Detecting genetic regions associated with height in the native ponies of the British Isles by using high density SNP genotyping ». Genome 61, n^o 10 (octobre 2018) : 767–70. http://dx.doi.org/10.1139/gen-2018-0006.

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Height is an important characteristic in the equine industry although little is known about its genetic control in native British breeds of ponies. This study aimed to map QTL data with the withers height in four pony breeds native to the British Isles, including two different sections within Welsh Cobs. In this study, a genome-wide analysis approach using the Illumina EquineSNP50 Infinium BeadChip was applied to 105 ponies and cobs. Analysis identified 222 highly significant height-associated SNPs (P ≤ 10−5), among which three SNPs on ECA9 have also been previously reported elsewhere. The highest number of significant SNPs associated to height in the native British horses were located on ECA1, ECA8, and ECA16.

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Aydoğan, Reyhan, Tim Baarslag et Enrico Gerding. « Artificial Intelligence Techniques for Conflict Resolution ». Group Decision and Negotiation 30, n^o 4 (28 mai 2021) : 879–83. http://dx.doi.org/10.1007/s10726-021-09738-x.

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AbstractConflict resolution is essential to obtain cooperation in many scenarios such as politics and business, as well as our day to day life. The importance of conflict resolution has driven research in many fields like anthropology, social science, psychology, mathematics, biology and, more recently, in artificial intelligence. Computer science and artificial intelligence have, in turn, been inspired by theories and techniques from these disciplines, which has led to a variety of computational models and approaches, such as automated negotiation, group decision making, argumentation, preference aggregation, and human-machine interaction. To bring together the different research strands and disciplines in conflict resolution, the Workshop on Conflict Resolution in Decision Making (COREDEMA) was organized. This special issue benefited from the workshop series, and consists of significantly extended and revised selected papers from the ECAI 2016 COREDEMA workshop, as well as completely new contributions.

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COENEN, FRANS, TREVOR BENCH-CAPON, ROBIN BOSWELL, JULIETTE DIBIE-BARTHÉLEMY, BARRY EAGLESTONE, RIK GERRITS, ERIC GRÉGOIRE et al. « Validation and verification of knowledge-based systems : report on EUROVAV99 ». Knowledge Engineering Review 15, n^o 2 (juin 2000) : 187–96. http://dx.doi.org/10.1017/s0269888900002010.

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Knowledge-Based (KB) technology is being applied to complex problem solving and safety and business critical tasks in many application domains. Concerns have naturally arisen as to the dependability of Knowledge-Based Systems (KBS). As with any software, attention to quality and safety must be paid throughout development of a KBS, and rigorous Verification and Validation (V&V) techniques must be employed. Research in V&V of KBSs has emerged as a distinct field only in the last decade, and is intended to address issues associated with quality and safety aspects of KBSs, and to provide such applications with the same degree of dependability as conventional applications. In recent years, V&V of KBSs has been the topic of annual workshops associated with the main AI conferences, such as AAAI, IJCAI and ECAI.

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SOININEN, TIMO, et MARKUS STUMPTNER. « Special Issue : Configuration ». Artificial Intelligence for Engineering Design, Analysis and Manufacturing 17, n^o 1 (février 2003) : 1–2. http://dx.doi.org/10.1017/s0890060403171016.

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The configuration task is commonly defined as composing a complex product from a set of predefined component types while taking into account a set of well-defined restrictions on how components belonging to these types can be combined. Configuration, always a successful artificial intelligence (AI) application area ever since the R1/XCON system of the early 1980s, has recently attracted renewed research interest. This is also demonstrated by an annual series of workshops on configuration that have been held at the AAAI, ECAI, and IJCAI conferences since 1999. Important real-world industrial configuration tasks are encountered in marketing, manufacturing, and design. They usually involve physical products, such as telecommunication switches, computers, elevators, large diesel engines, automation systems, or vehicles (some of which appear as application domains in the articles in this issue), but can also pertain to financial or other services or software.

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Manjasetty, Babu A., et Mark R. Chance. « Crystal Structure of Escherichia coli L-Arabinose Isomerase (ECAI), The Putative Target of Biological Tagatose Production ». Journal of Molecular Biology 360, n^o 2 (juillet 2006) : 297–309. http://dx.doi.org/10.1016/j.jmb.2006.04.040.

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So, Anthony KC, Harriette GC Van Spall, John R. Coleman et George S. Espie. « Catalytic exchange of 18O from 13C18O-labelled CO2 by wild-type cells and ecaA, ecaB, and ccaA mutants of the cyanobacteria Synechococcus PCC7942 and Synechocystis PCC6803 ». Canadian Journal of Botany 76, n^o 6 (1 juin 1998) : 1153–60. http://dx.doi.org/10.1139/b98-063.

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Expression constructs carrying the ecaA, ecaB, and ccaA genes from the cyanobacteria Synechococcus PCC7942 and Synechocystis PCC6803 were generated and each transformed into Escherichia coli. Lysates from cells expressing recombinant protein were prepared and assayed using mass spectrometry for their ability to catalyze the exchange of 18O from 13C18O to H2O. No carbonic anhydrase (CA) activity was detected from the cell lysates containing recombinant EcaA or EcaB proteins, whereas the lysate harbouring the CcaA polypeptide clearly accelerated the rate of 18O exchange. An ecaA deletion mutant in Synechococcus and insertionally inactivated ecaB and ccaA mutants in Synechocystis were generated and similarly assessed for CA activity. All mutants displayed a transient, ethoxyzolamide-sensitive, CA-like catalysis that was also exhibited by wild-type cells. The CcaA-deficient mutant showed a reduced capacity to exchange 18O out of 13C18O-labelled CO2 in the light as well as an absolute requirement for high Ci for growth, reflecting the importance of the carboxysomal CA to the operation of the cyanobacterial CO2-concentrating mechanism. No detectable differences in 18O exchange patterns, CO2 or HCO3- transport, or steady-state growth were observed between the ecaA and ecaB mutants and wild-type cells, indicating that neither EcaA nor EcaB play an essential catalytic role in the functioning of the CO2-concentrating mechanism.Key words: carbonic anhydrase, CO2-concentrating mechanism, cyanobacteria, 18O exchange, Synechococcus PCC7942, Synechocystis PCC6803.

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Távora, Flora Freitas Fernandes, Ana Paula Chappuis Chocano, Denise Gusmão de Oliveira, Jefferson Ricardo Pereira, Ricardo Sergio Almeida, Karin Hermana Neppelenbroek et Vinícius Carvalho Porto. « Beneficial Effects of Ethyl-Cyanoacrylate Coating Against Candida Albicans Biofilm Formation ». Brazilian Dental Journal 30, n^o 3 (juin 2019) : 266–71. http://dx.doi.org/10.1590/0103-6440201901953.

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Abstract The aim of this study was to verify whether modifications made in a hard chairside reline resin by an ethyl-cyanoacrylate adhesive, ECA (Super Bonder®, Loctite, Itapevi, SP, Brazil) would be able to inhibit or reduce Candida albicans biofilm formation on its surface, comparing to a commercial surface sealant (BisCover®, Bisco, Schaumburg, USA). Reline resin specimens were fabricated and randomly divided into 6 groups (n=8): CG (control group), no surface treatment; ECA1, ECA coating on the surface before sterilization; ECA2, ECA coating after sterilization; ECA3, ECA incorporated in the resin bulk; DPE1, BisCover® coating before sterilization; DPE2, BisCover® coating after sterilization. Specimens were inoculated with C. albicans SC5314 (1x107 cells/mL) and incubated for 24 h. Then, the biofilm were stained with LIVE/DEAD® BaclightTM L7007 Kit and analyzed by Confocal Laser Scanning Microscopy. The images were evaluated by bioImageL® v.2.0 software and total biovolume (µm3), viable cells (%), and covered area (%) were calculated. Data were statistically analyzed by Kruskal-Wallis and Dunn tests (p<0.05). Results showed that ECA-coated groups presented better results, reducing C. albicans biofilm formation. Acquired images revealed that these groups (ECA1 and ECA2) presented a reduced number of cells, mostly in yeast form (less pathogenic), while the other groups presented higher number of cells, mostly in hyphae form (more pathogenic). Based on these findings, a beneficial effect of Super Bonder® coating reline resins surface could be demonstrated, suggesting a promising way to prevent fungal biofilm formation on dentures.

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Higuera-Cobos, Oscar Fabián, Luis Carlos Flórez-García et Cristian Antonio Pedraza-Yepes. « Análisis por elementos finitos de la deformación aplicada a la aleación de aluminio 6061-T6 mediante presión en canal angular de sección constante ». Revista Facultad de Ingeniería 28, n^o 50 (10 janvier 2019) : 7–18. http://dx.doi.org/10.19053/01211129.v28.n50.2019.8781.

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El proceso de deformación plástica severa “presión en canal angular de sección constante (ECAP/ECAE por sus siglas en inglés)”, se simuló bajo la teoría de elementos finitos utilizando el software ANSYS, aproximando respuestas elastoplásticas que se puedan presentar en una probeta de aleación de aluminio 6061-T6. Se estudiaron las variaciones de los parámetros mecánicos de la matriz ECAP, tales como su geometría (ángulo externo (Ψ) y ángulo interno (Φ)) y las condiciones de fricción del proceso. Se analizó la influencia de cada uno de estos parámetros en el comportamiento del material. Los resultados obtenidos fueron comparados con las predicciones teóricas que se han dispuesto a lo largo del estudio del ECAE/ECAP por parte de diferentes investigadores.

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Bruder, Enrico, Mehmet Okan Görtan, Peter Groche et Clemens Müller. « Severe Plastic Deformation by Equal Channel Angular Swaging ». Materials Science Forum 667-669 (décembre 2010) : 103–7. http://dx.doi.org/10.4028/www.scientific.net/msf.667-669.103.

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Equal Channel Angular Swaging (ECAS) is a new severe plastic deformation process which combines the conventional equal channel angular pressing (ECAP) and the incremental bulk forming process rotary swaging. The tool system consists of two rotary swaging dies with an angled channel that contains four shear zones, generating severe plastic strain per pass. The crucial advantages compared to conventional ECAP are a significant reduction of friction and axial forces plus the potential to be extended to continuous processing. Thus, ECAS has high potential for a cost-efficient production of bulk UFG materials. In the present paper the principles of ECAS are introduced and first experimental results for the processing of copper are presented.

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dos Santos, Angélica Rossotti, Marceléia Rubert, Lucia Giuliano-Caetano et Ana Lúcia Dias. « Sympatric occurrence of four cytotypes and one extra chromosome in Bryconamericus ecai (Characidae) : 18S rDNA polymorphism and heterochromatin composition ». Hereditas 149, n^o 1 (24 janvier 2012) : 24–33. http://dx.doi.org/10.1111/j.1601-5223.2011.02234.x.

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Nédellec, Claire. « Integration of Machine Learning and Knowledge Acquisition ». Knowledge Engineering Review 10, n^o 1 (mars 1995) : 77–81. http://dx.doi.org/10.1017/s026988890000730x.

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“Integration of Machine Learning and Knowledge Acquisition” may be a surprising title for an ECAI-94 workshop, since most machine learning (ML) systems are intended for knowledge acquisition (KA). So what seems problematic about integrating ML and KA? The answer lies in the difference between the approaches developed by what is referred to as ML and KA research. Apart from sonic major exceptions, such as learning apprentice tools (Mitchell et al., 1989), or libraries like the Machine Learning Toolbox (MLT Consortium, 1993), most ML algorithms have been described without any characterization in terms of real application needs, in terms of what they could be effectively useful for. Although ML methods have been applied to “real world” problems few general and reusable conclusions have been drawn from these knowledge acquisition experiments. As ML techniques become more and more sophisticated and able to produce various forms of knowledge, the number of possible applications grows. ML methods tend then to be more precisely specified in terms of the domain knowledge initially required, the control knowledge to be set and the nature of the system output (MLT Consortium, 1993; Kodratoff et al., 1994).

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Jespersen, Joergen, A. M. H. P. van den Besselaar, Felix van der Meer, Gualtiero Palareti, Armando Tripodi, Caroline Shiach, Michelle Keown, Saied Ibrahim et Leon Poller. « External quality assessment (EQA) for CoaguChek monitors ». Thrombosis and Haemostasis 103, n^o 05 (2010) : 936–41. http://dx.doi.org/10.1160/th09-10-0683.

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SummaryAnticoagulant control facilities are being overwhelmed by requests for monitoring and large numbers of patients are not therefore receiving treatment. Procedures designed for point-of-care testing have therefore been developed, the most popular being the CoaguChek. The need for external quality assessment (EQA) of monitors used by patients in self-management has been stressed in a European Commission (EC) Directive. It would not however be feasible for all CoaguChek monitors to be enrolled in national or regional EQA schemes which take time to organise and analyse. The European Concerted Action on Anticoagulation (ECAA) has therefore evolved a simpler system. Its value has been assessed in collaboration with the European Concerted Action on Thrombosis (ECAT). 523 monitors were tested at nine clinics which asked patients to bring their CoaguChek instruments to be assessed with the ECAA/ECAT procedure based on a set of 5 plasma samples with certified international normalised ratios (INR). 15% or more deviation from the certified INR on a single certified plasma sample from the set was defined by the ECAA as the limit of acceptable performance. One hundred and six (20.3%) of the monitors tested showed significant deviation and higher than average incidence of significant INR deviations reported with one specific numbered lot of test strips. Recent ECAA/ECAT, Danish and Italian studies report regular EQA of CoaguChek monitors is essential. There is general agreement that this should be performed at reasonably frequent intervals, at six months or whenever there is a change of the manufacturer’s test strips.

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Bellacicco, A. « Advances in artificial intelligence : Proceedings of the Sixth European Conference on Artificial Intelligence, ECAI-84, Pisa, Italy, September 5–7, 1984 ». European Journal of Operational Research 33, n^o 3 (février 1988) : 355–56. http://dx.doi.org/10.1016/0377-2217(88)90186-5.

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Luri, R., C. J. Luis, J. León et M. A. Sebastian. « A New Configuration for Equal Channel Angular Extrusion Dies ». Journal of Manufacturing Science and Engineering 128, n^o 4 (22 février 2006) : 860–65. http://dx.doi.org/10.1115/1.2194555.

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Equal channel angular extrusion or pressing (ECAE or ECAP) is a process used in order to impart severe plastic deformations to processed materials with the aim of improving their mechanical properties by reducing the grain size. The grain size reduction leads to mechanical properties improvement. In the present study, a new die configuration is proposed for the ECAE process. The advantage of this die geometry is that it allows us to obtain higher plastic strain in each ECAE passage than traditional ECAE dies. It is important to optimize the die geometry, as the main aim of the ECAE process is to impart severe plastic deformations to the processed materials. Consequently, the higher the deformation, the better the improvement on the mechanical properties of the processed materials. In order to determine how variations on geometry affect the plastic strain of the processed materials finite element modeling (FEM) is used. Both analytical and FEM methods will allow us to affirm that by using this new die configuration it is possible to achieve higher deformation values per ECAE passage.

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Xu, Shu Bo, Cai Nian Jing, Guo Cheng Ren et Guo Qun Zhao. « Finite Element Simulation of Die Design for Equal Channel Angular Extrusion Process of Pure Aluminum and its Experimental Investigation ». Advanced Materials Research 146-147 (octobre 2010) : 1737–40. http://dx.doi.org/10.4028/www.scientific.net/amr.146-147.1737.

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equal channel angular extrusion/Pressing (ECAE, ECAP) has the capability of producing ultra-fined grain (UFG) materials bellow the dimension of 1 μm. At present, it is one of the most important methods to get bulk UFG materials. In this paper, a systematic investigation of ECAP process on the pure Aluminum and die design is performed by using numerical simulation. The stress distributions on the die were obtained, and general consideration of the die during the whole pressing process was given. it was found that the closer the die corner is, the higher stress value results can be acquired. And the effective stress concentration in ECAP die cavity corner. The extruding load fell rapidly when the angular angle increasing. The proposed method can serve as preconditions to analyze the abrasion and fatigue of ECA Pressing die.

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Perig, A. V., et N. N. Golodenko. « ECAP process improvement based on the design of rational inclined punch shapes for the acute-angled Segal 2θ-dies : CFD 2-D description of dead zone reduction ». Mechanical Sciences 6, n^o 1 (14 avril 2015) : 41–49. http://dx.doi.org/10.5194/ms-6-41-2015.

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Abstract. This article is focused on a 2-D fluid dynamics description of punch shape geometry improvement for Equal Channel Angular Extrusion (ECAE) or Equal Channel Angular Pressing (ECAP) of viscous incompressible continuum through acute-angled Segal 2θ-dies with 2θ < 90°. It has been shown both experimentally with physical simulation and theoretically with computational fluid dynamics that for the best efficiency under the stated conditions, the geometric condition required is for the taper angle 2θ0 of the inclined oblique punch to be equal to the 2θ angle between the inlet and outlet channels of the Segal 2θ-die. Experimentally and theoretically determined rational geometric condition for the ECAP punch shape is especially prominent and significant for ECAP through the acute angled Segal 2θ-dies. With the application of Navier-Stokes equations in curl transfer form it has been shown that for the stated conditions, the introduction of an oblique inclined 2θ0-punch results in dead zone area downsizing and macroscopic rotation reduction during ECAP of a viscous incompressible continuum. The derived results can be significant when applied to the improvement of ECAP processing of both metal and polymer materials through Segal 2θ-dies.

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Zhilyaev, Alexandre P., Terry R. McNelley et Oscar A. Ruano. « Microstructure and Texture Evolution in Metals and Alloys during Intense Plastic Deformation ». Materials Science Forum 715-716 (avril 2012) : 51–60. http://dx.doi.org/10.4028/www.scientific.net/msf.715-716.51.

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ntense plastic deformation is generally effective in producing grain refinement. IPD methods include equal channel angular pressing/extrusion (ECAP/ECAE), high-pressure torsion (HPT), accumulative roll bonding (ARB), and friction stir processing (FSP), among others. In this work, we summarize the main results on grain refinement by these processing methods and present our own data on microstructure and texture evolution in metals and alloys during ECAP, HPT and FSP. Whereas ECAP and HPT are usually performed with the work piece material initially at room temperature or even at liquid nitrogen temperature to enhance refinement, FSP involves a brief but complex thermomechanical cycle with peak temperatures up to 0.7 0.9 TMelt. Apparently, materials undergo dynamic recrystallization (DRX) during FSP. DRX also occurs also in metals and alloys of low TMeltdue to adiabatic heating during HPT performed at room temperature. The paper is devoted to revisiting of previous as well as new results and a comparative analysis of microstructure and texture evolution in commercially pure aluminum and selected pure metals and alloys during ECAP, HPT and FSP in order to illustrate the limits of grain refinement.

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Freitas, Ednardo Rodrigues, Ângela da Silva Borges, Maria Teresa Salles Trevisan, André Luís da Cunha, Nádia de Melo Braz, Pedro Henrique Watanabe et Germano Augusto Jerônimo do Nascimento. « Extratos etanólicos de manga como antioxidantes na alimentação de poedeiras ». Pesquisa Agropecuária Brasileira 48, n^o 7 (juillet 2013) : 714–21. http://dx.doi.org/10.1590/s0100-204x2013000700003.

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O objetivo deste trabalho foi avaliar o efeito de extratos etanólicos do caroço e da casca de manga, sobre o desempenho de poedeiras e sobre a qualidade e estabilidade lipídica dos ovos. Um total de 180 poedeiras comerciais Hisex White foi distribuído ao acaso em seis tratamentos, com cinco repetições de seis aves. Os tratamentos consistiram de: ração sem adição de antioxidante; ração com 200 ppm do antioxidante butilato de hidroxitolueno (BHT); ração com 200 ou 400 ppm de extrato da casca de manga (Ecas); ração com 200 ou 400 ppm de extrato de caroço de manga (Ecar). Foram avaliados: o consumo de ração, a produção de ovos, o peso do ovo, a massa de ovo produzida (grama por ave por dia), a conversão alimentar e características de qualidade dos ovos. A oxidação lipídica da gema durante o armazenamento foi determinada pela quantificação das substâncias reativas ao ácido tiobarbitúrico. As aves alimentadas com a ração sem adição de antioxidantes produziram ovos com os piores valores de unidade Haugh e maior oxidação lipídica da gema. Os teores de 400 ppm de Ecas e 200 ou 400 ppm de Ecar foram efetivos na prevenção de danos oxidativos aos ovos durante o armazenamento e podem ser utilizados na alimentação das poedeiras como substituto ao antioxidante sintético.

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Silva, Kayla Gisela, Leonor Martins, Miguel Teixeira, Joël F. Pothier et Fernando Tavares. « DNA Markers for Detection and Genotyping of Xanthomonas euroxanthea ». Microorganisms 10, n^o 6 (24 mai 2022) : 1078. http://dx.doi.org/10.3390/microorganisms10061078.

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Xanthomonas euroxanthea is a bacterial species encompassing both pathogenic and non-pathogenic strains and is frequently found colonizing the same host plants as X. arboricola. This presents the need to develop a detection and genotyping assay able to track these bacteria in microbial consortia with other xanthomonads. Eight X. euroxanthea-specific DNA markers (XEA1-XEA8) were selected by comparative genomics and validated in silico regarding their specificity and consistency using BLASTn, synteny analysis, CG content, codon usage (CAI/eCAI values) and genomic proximity to plasticity determinants. In silico, the selected eight DNA markers were found to be specific and conserved across the genomes of 11 X. euroxanthea strains, and in particular, five DNA markers (XEA4, XEA5, XEA6, XEA7 and XEA8) were unfailingly found in these genomes. A multiplex of PCR targeting markers XEA1 (819 bp), XEA8 (648 bp) and XEA5 (295 bp) was shown to successfully detect X. euroxanthea down to 1 ng of DNA (per PCR reaction). The topology of trees generated with the concatenated sequences of three markers (XEA5, XEA6 and XEA8) and four housekeeping genes (gyrB, rpoD, fyuA and acnB) underlined the equal discriminatory power of these features and thus the suitability of the DNA markers to discriminate X. euroxanthea lineages. Overall, this study displays a DNA-marker-based method for the detection and genotyping of X. euroxanthea strains, contributing to monitoring for its presence in X. arboricola-colonizing habitats. The present study proposes a workflow for the selection of species-specific detection markers. Prospectively, this assay could contribute to unveil alternative host species of Xanthomonas euroxanthea; and improve the control of phytopathogenic strains.

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Grosdidier, Thierry, et Núria Llorca-Isern. « Processing Dense Hetero-Nanostructured Metallic Materials for Improved Strength/Ductility Balance through High Strain Deformation and Electrical Current Assisted Sintering (ECAS) ». Materials Science Forum 633-634 (novembre 2009) : 559–67. http://dx.doi.org/10.4028/www.scientific.net/msf.633-634.559.

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This paper has examined some recent findings concerning the processing of fully dense hetero-nanostructured materials (i.e. consisting of nano, ultrafine and micrometric grains) which can be produced by using the interplay between heavy deformation and recrystallization. By plastic deformation of bulk materials, an improved strength/ductility balance can be obtained directly by imparting high strain deformation (by ECAE) until the occurrence of recrystallization. Using a powder metallurgy route, the strong potential of electric field assisted sintering (ECAS) for producing multi-scale microstructures when a milled powder is used is also demonstrated. In this case, in addition to modify the classic processing parameters (time/temperature of ECAS), altering the nature of the milled powder - by Y2O3 addition during the milling stage - is also a good way to delay the onset of recrystallization and, thereby, increase the fraction of ultrafine grains.

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Yan, Yingwei, Kenneth Dean, Chen-Chieh Feng, Guan Thye Hue, Khee-heong Koh, Lily Kong, Chang Woei Ong, Arthur Tay, Yi-chen Wang et Yiran Xue. « Chinese Temple Networks in Southeast Asia : A WebGIS Digital Humanities Platform for the Collaborative Study of the Chinese Diaspora in Southeast Asia ». Religions 11, n^o 7 (6 juillet 2020) : 334. http://dx.doi.org/10.3390/rel11070334.

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This article introduces a digital platform for collaborative research on the Chinese diaspora in Southeast Asia, focusing on networks of Chinese temples and associations extending from Southeast China to the various port cities of Southeast Asia. The Singapore Historical Geographic Information System (SHGIS) and the Singapore Biographical Database (SBDB) are expandable WebGIS platforms gathering and linking data on cultural and religious networks across Southeast Asia. This inter-connected platform can be expanded to cover not only Singapore but all of Southeast Asia. We have added layers of data that go beyond Chinese Taoist, Buddhist, and popular god temples to also display the distributions of a wide range of other religious networks, including Christian churches, Islamic mosques, Hindu temples, and Theravadin, which are the Taiwanese, Japanese and Tibetan Buddhist monasteries found across the region. This digital platform covers a larger area than the Taiwan History and Culture in Time and Space (THCTS) historical GIS platform but is more regionally focused than the ECAI (Electronic Cultural Atlas Initiative) By incorporating Chinese inscriptions, extensive surveys of Chinese temples and associations, as well as archival and historical sources, this platform provides new materials and new perspectives on the Chinese diaspora in Southeast Asia. This paper: (1) outlines key research questions underlying these digital humanities platforms; (2) describes the overall architecture and the kinds of data included in the SHGIS and the SBDB; (3) reviews past research on historical GIS; and provides (4) a discussion of how incorporating Chinese epigraphy of Southeast Asia into these websites can help scholars trace networks across the entire region, potentially enabling comparative work on a wide range of religious networks in the region. Part 5 of the paper outlines technical aspects of the WebGIS platform.

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Manjunath, G. K. « Optimization of processing conditions in equal channel angular pressing for superior structure and properties ». Journal of Mines, Metals and Fuels 69, n^o 12A (28 avril 2022) : 317. http://dx.doi.org/10.18311/jmmf/2021/30121.

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In the past 25 years, much interest has been paid to the production of ultrafine-grained (UFG) materials due to their superior structure and properties. Equal channel angular extrusion or pressing (ECAE or ECAP) is one of the severe plastic deformation (SPD) technique used to produce UFG materials. Compared to other SPD process, higher strain per pass and higher total productive strain after ‘n’ number of passes is possible in this technique. ECAP process is affected by various processing conditions or parameters. These processing conditions mainly affects the structure and properties produced through this technique. In this article, an effort has been made to provide the effect of each processing parameter on the structure and properties developed through this technique. Various processing conditions like- processing route, channel angle, outer arc of curvature, pressing speed, load and friction, processing temperature and application of back-pressure are critically discussed and effect of these parameters are summarized.

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León, Javier, C. J. Luis-Pérez, Daniel Salcedo, Ivan Pérez, Juan Pablo Fuertes, Ignacio Puertas et Rodrigo Luri. « Experimental and FEM Analysis of the AA 6082 Processed by Equal Channel Angular Extrusion ». Key Engineering Materials 478 (avril 2011) : 46–53. http://dx.doi.org/10.4028/www.scientific.net/kem.478.46.

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Recent studies have shown that severe plastic deformation processes (SPD) improve the mechanical properties of the processed parts. Some of the most outstanding SPD processes are as follows: High Pressure Torsion (HPT), Repetitive Corrugation and Straightening (RCS), Cyclic Extrusion Compression (CEC), Accumulative Roll Bonding (ARB), Conform and Continuous Combined Drawing and Rolling (CCDR), among others, but the most well-known is Equal Channel Angular Extrusion or Pressure (ECAE/ECAP). The aim of these processes is to introduce high values of deformation inside the parts in order to reduce the grain size and thus to improve the mechanical properties of the starting material. The study of the damage imparted to an AA-6082 alloy is made in the present work. This alloy is received as cast and it is quenched at a temperature of 530 °C during 4 hours in order to be processed by ECAE at room temperature using different geometries of the dies. The imparted damage is also studied by using FEM simulations.

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Xu, Shu Bo, Cai Nian Jing, Guo Cheng Ren et Peng Liu. « Finite Element Simulation of Die Design for Warm Equal Channel Angular Extrusion Process of AZ31 Alloy and its Experimental Investigation ». Materials Science Forum 667-669 (décembre 2010) : 75–79. http://dx.doi.org/10.4028/www.scientific.net/msf.667-669.75.

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In this paper, a systematic investigation of equal channel angular extrusion/Pressing (ECAE, ECAP) process on the AZ31 alloy and die design is performed by using numerical simulation. The stress distributions on the die were obtained, and general consideration of the die during the whole pressing process was given. The numerical results revealed that effective stress distribution at the corner of the cavity and the extruded load during extrusion processes was effect by channel angles and friction factor. From the simulations, it was found that the closer the die corner is, the higher stress value results can be acquired. And the effective stress concentration in ECAP die cavity corner. The extruding load fell rapidly when the angular angle increasing. With the increase of friction factor, extruding load also increased significantly. The proposed method can serve as preconditions to analyze the abrasion and fatigue of ECA Pressing die. Besides, this method also provides a feasible way for other die stress analysis.

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Khongnawang, Tibet, Ehsan Zare, Dongxue Zhao, Pranee Srihabun et John Triantafilis. « Three-Dimensional Mapping of Clay and Cation Exchange Capacity of Sandy and Infertile Soil Using EM38 and Inversion Software ». Sensors 19, n^o 18 (12 septembre 2019) : 3936. http://dx.doi.org/10.3390/s19183936.

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Most cultivated upland areas of northeast Thailand are characterized by sandy and infertile soils, which are difficult to improve agriculturally. Information about the clay (%) and cation exchange capacity (CEC—cmol(+)/kg) are required. Because it is expensive to analyse these soil properties, electromagnetic (EM) induction instruments are increasingly being used. This is because the measured apparent soil electrical conductivity (ECa—mS/m), can often be correlated directly with measured topsoil (0–0.3 m), subsurface (0.3–0.6 m) and subsoil (0.6–0.9 m) clay and CEC. In this study, we explore the potential to use this approach and considering a linear regression (LR) between EM38 acquired ECa in horizontal (ECah) and vertical (ECav) modes of operation and the soil properties at each of these depths. We compare this approach with a universal LR relationship developed between calculated true electrical conductivity (σ—mS/m) and laboratory measured clay and CEC at various depths. We estimate σ by inverting ECah and ECav data, using a quasi-3D inversion algorithm (EM4Soil). The best LR between ECa and soil properties was between ECah and subsoil clay (R2 = 0.43) and subsoil CEC (R2 = 0.56). We concluded these LR were unsatisfactory to predict clay or CEC at any of the three depths, however. In comparison, we found that a universal LR could be established between σ with clay (R2 = 0.65) and CEC (R2 = 0.68). The LR model validation was tested using a leave-one-out-cross-validation. The results indicated that the universal LR between σ and clay at any depth was precise (RMSE = 2.17), unbiased (ME = 0.27) with good concordance (Lin’s = 0.78). Similarly, satisfactory results were obtained by the LR between σ and CEC (Lin’s = 0.80). We conclude that in a field where a direct LR relationship between clay or CEC and ECa cannot be established, can still potentially be mapped by developing a LR between estimates of σ with clay or CEC if they all vary with depth.

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