Academic literature on the topic 'Partitive Division'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Partitive Division.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Partitive Division"
1
Ott, Jack M., Daniel L. Snook, and Diana L. Gibson. "Understanding Partitive Division of Fractions." Arithmetic Teacher 39, no. 2 (October 1991): 7–11. http://dx.doi.org/10.5951/at.39.2.0007.
Full textAbstract:
When first-grade students start addition of whole numbers, they are given sets of objects to combine and count to determine the sum. Most educators agree that beginning students need experience combining group or objects, such as combining two pencils and three pencils to get a group of five pencils. Such activities are needed to give students an understanding of what addition means before moving on to faster — but less meaningful — ways to sum numbers, such as the use of an algorithm or calculator. This approach is based on the learning principle that meaning comes from knowing the things signified by the symbols. Thus, familiar, concrete experience — actual or recalled — should be a first step in the development of new abstract concepts and their symbolization. Though this principle of moving from the concrete to the abstract is extensively used in teaching the addition of whole numbers, it is used much less in teaching the division of fractions. The inevitable result in that a student may be able to use an algorithm by rote to divide fractions, but the skill is useless because it is devoid of meaning.
2
Huumo, Tuomas. "Moni or monta? The collective vs. distributive opposition between two forms of the quantifier ‘many’ in Finnish." Eesti ja soome-ugri keeleteaduse ajakiri. Journal of Estonian and Finno-Ugric Linguistics 8, no. 2 (September 6, 2017): 7–33. http://dx.doi.org/10.12697/jeful.2017.8.2.01.
Full textAbstract:
In this work I explore the semantics of two case forms of the Finnish quantifier moni ‘many’: the regular nominative moni and the regular partitive monta [mon-ta many-PARTITIVE], which however has taken on a function similar to that of the nominative of numerals and is thus not a functional partitive anymore. This development has apparently motivated the rise of the pleonastic montaa [mon-ta-a many-PARTITIVE-PARTITIVE] to unambiguously mark the partitive. I argue that an important difference between moni and monta is the opposition between a distributive and a collective meaning: in ambiguous contexts, moni is clearly distributive and monta collective. I compare the two with the nominative form of the near-synonymous quantifier usea ‘several; a number of’ which in similar contexts displays ambiguity between the distributive and collective readings. The analysis sheds new light to the division of labor between the two (functional) nominative forms of moni, showing that they divide the functions of the nominative in an idiosyncratic way.Kokkuvõte. Tuomas Huumo: Moni või monta? Distributiivse ja kollektiivse tähenduse vastandus soome keele kvantori moni ‘mitu’ kahe käändevormi vahel. Artikkel käsitleb soome keele kvantori moni ‘mitu’ kahe käändevormi tähenduserinevusi. Võrdlusobjektideks on reeglipärane nominatiiv moni ning reeglipäraselt moodustatud partitiivivorm monta [mon-ta mitu-PARTITIIV ‘mitut’], millel siiski on tekkinud arvsõnade nominatiivile sarnane funktsioon ning mis seetõttu ei ole enam funktsionaalne partitiiv. See areng on tõenäoliselt motiveerinud ka pleonastilise, kahe partitiivilõpuga vormi mon-ta-a [mitu-PARTITIIV-PARTITIIV] teket, mis väljendab ühetähenduslikult partitiivi funktsioone. Artikli põhiväide on, et oluline erinevus vormide moni ja monta vahel on distributiivse ja kollektiivse tähenduse vastandamine: mitmetitõlgendatavates kontekstides annab moni edasi distributiivset, monta aga kollektiivset tähendust. Artiklis võrreldakse nimetatud kaht vormi lisaks ka semantiliselt lähedase kvantori usea ‘mitu; arvukas’ nominatiivivormiga. Usea on sarnastes kontekstides mitmetähenduslik ning võib edasi anda nii distributiivset kui ka kollektiivset tähendust. Kokkuvõttes valgustab analüüs seni käsitlemata vaatenurgast kvantori moni kahe (funktsionaalses mõttes nominatiivi-)vormi tööjaotust, mis on üsnagi idiosünkraatiline.Võtmesõnad: kvantor; kääne; partitiiv; kollektiivne vs. distributiivne tähendus; soome keel
3
Jong, Cindy, and Robin Magruder. "Beyond Cookies: Understanding Various Division Models." Teaching Children Mathematics 20, no. 6 (February 2014): 366–73. http://dx.doi.org/10.5951/teacchilmath.20.6.0366.
Full text
4
Kouba, Vicky L. "Children's Solution Strategies for Equivalent Set Multiplication and Division Word Problems." Journal for Research in Mathematics Education 20, no. 2 (March 1989): 147–58. http://dx.doi.org/10.5951/jresematheduc.20.2.0147.
Full textAbstract:
One hundred twenty-eight children in Grades 1, 2, and 3 were given two multiplication and four division word problems that differed in semantic structure. The children's solution strategies were classified by degree of abstraction into direct representation, double counting, transitional counting, additive or subtractive, or recalled number fact. Strategies were also classified by use of physical objects: use as representations of individual elements, use as tallies or repeated references, or no use. Analyses of the solution strategies indicated the existence of a two-step intuitive model for multiplication, two common intuitive models for partitive division and measurement division each of which was related to an intuitive model for subtraction, and a third model for partitive division.
5
Wahyu, Kamirsyah, Taha Ertugrul Kuzu, Sri Subarinah, Dwi Ratnasari, and Sofyan Mahfudy. "PARTITIVE FRACTION DIVISION: REVEALING AND PROMOTING PRIMARY STUDENTS’ UNDERSTANDING." Journal on Mathematics Education 11, no. 2 (April 17, 2020): 237–58. http://dx.doi.org/10.22342/jme.11.2.11062.237-258.
Full textAbstract:
Students show deficient understanding on fraction division and supporting that understanding remains a challenge for mathematics educators. This article aims to describe primary students’ understanding of partitive fraction division (PFD) and explore ways to support their understanding through the use of sequenced fractions and context-related graphical representations. In a design-research study, forty-four primary students were involved in three cycles of teaching experiments. Students’ works, transcript of recorded classroom discussion, and field notes were retrospectively analyzed to examine the hypothetical learning trajectories. There are three main findings drawn from the teaching experiments. Firstly, context of the tasks, the context-related graphical representations, and the sequence of fractions used do support students’ understanding of PFD. Secondly, the understanding of non-unit rate problems did not support the students’ understanding of unit rate problems. Lastly, the students were incapable of determining symbolic representations from unit rate problems and linking the problems to fraction division problems. The last two results imply to rethink unit rate as part of a partitive division with fractions. Drawing upon the findings, four alternative ways are offered to support students’ understanding of PFD, i.e., the lesson could be starting from partitive whole number division to develop the notion of fair-sharing, strengthening the concept of unit in fraction and partitioning, choosing specific contexts with more relation to the graphical representations, and sequencing the fractions used, from a simple to advanced form.
6
Fischbein, Efraim, Maria Deri, Maria Sainat Nello, and Maria Sciolis Marino. "The Role of Implicit Models in Solving Verbal Problems in Multiplication and Division." Journal for Research in Mathematics Education 16, no. 1 (January 1985): 3–17. http://dx.doi.org/10.5951/jresematheduc.16.1.0003.
Full textAbstract:
Arithmetical operations were assumed to remain attached to primitive behavioral models that influence tacitly the choice of an operation even after the learner has had solid formal-algorithmic training. The model for multiplication was conjectured to be repeated addition, and two primitive models (partitive and quotative) were seen as linked to division. A total of 623 pupils enrolled in 13 Italian schools (Grades 5, 7, and 9) were asked to choose the operation needed to solve 26 multiplication and division word problems. Violations by the numerical data of the constraints imposed by the assumed tacit models (for instance, when the operator was a decimal number) constituted particular sources of difficulty at all three grade levels. The findings seemed to confirm the impact of the repeated addition model on multiplication and of the partitive model on division. The quotative division model influenced the pupils' choices only at the ninth-grade level.
7
Moyer, Patricia Seray. "Links to Literature: A Remainder of One: Exploring Partitive Division." Teaching Children Mathematics 6, no. 8 (April 2000): 517–21. http://dx.doi.org/10.5951/tcm.6.8.0517.
Full textAbstract:
Children's literature can be a springboard for conversations about mathematical concepts. Austin (1998) suggests that good children's literature with a mathematical theme provides a context for both exploring and extending mathematics problems embedded in stories. In the context of discussing a story, children connect their everyday experiences with mathematics and have opportunities to make conjectures about quantities, equalities, or other mathematical ideas; negotiate their understanding of mathematical concepts; and verbalize their thinking. Children's books that prompt mathematical conversations also lead to rich, dynamic communication in the mathematics classroom and develop the use of mathematical symbols in the context of communicating. The National Council of Teachers of Mathematics (1989) emphasizes the importance of communication in helping children both construct mathematical knowledge and link their informal notions with the abstract symbols used to express mathematical ideas.
8
Simon, Martin A. "Prospective Elementary Teachers' Knowledge of Division." Journal for Research in Mathematics Education 24, no. 3 (May 1993): 233–53. http://dx.doi.org/10.5951/jresematheduc.24.3.0233.
Full textAbstract:
Prospective teachers' knowledge of division was investigated through an open-response written instrument and through individual interviews. Problems were designed to focus on two aspects of understanding division: connectedness within and between procedural and conceptual knowledge and knowledge of units. Results indicated that the prospective teachers' conceptual knowledge was weak in a number of areas including the conceptual underpinnings of familiar algorithms, the relationship between partitive and quotitive division, the relationship between symbolic division and real-world problems, and identification of the units of quantities encountered in division computations. The research also characterized aspects of individual conceptual differences. The research results suggest conceptual areas of emphasis for the mathematical preparation of elementary teachers.
9
Hohensee, Charles, and Amanda Jansen. "Elementary Preservice Teachers’ Transitional Conceptions of Partitive Division with Proper-Fraction Divisors." Mathematical Thinking and Learning 19, no. 4 (October 2, 2017): 210–36. http://dx.doi.org/10.1080/10986065.2017.1346452.
Full text
10
Jansen, Amanda, and Charles Hohensee. "Examining and elaborating upon the nature of elementary prospective teachers’ conceptions of partitive division with fractions." Journal of Mathematics Teacher Education 19, no. 6 (June 30, 2015): 503–22. http://dx.doi.org/10.1007/s10857-015-9312-0.
Full textDissertations / Theses on the topic "Partitive Division"
1
Walsh, Patrick. "Myths of division : a comparative study of the work and influence of Daniel Corkery and John Hewitt." Thesis, University of Ulster, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274564.
Full text
2
Zong, Qiuling. "Interactions of the parA protein in the partition of DNA during bacterial cell division /." Click for abstract, 1997. http://library.ctstateu.edu/ccsu%5Ftheses/1513.html.
Full textAbstract:
Thesis (M.A.)--Central Connecticut State University, 1997.Thesis advisor: Kathy A. Martin-Troy, Ph. D. "... in partial fulfillment of the requirements for the degree of Master of Arts in Biology." Includes bibliographical references (leaves 23-24).
3
Ah-Seng, Yoan. "La Ségrégation du plasmide F d'Escherichia coli : régulation de l'activité ATPase de la protéine moteur de partition SopA." Toulouse 3, 2010. http://thesesups.ups-tlse.fr/1126/.
Full textAbstract:
La ségrégation, ou partition, des chromosomes et des plasmides bactériens est l'étape fondamentale du cycle cellulaire qui assure la transmission de l'ensemble du génome aux cellules filles. C'est l'équivalent procaryote de la mitose. Des systèmes de ségrégation, appelés les loci par, ont été identifiés sur les plasmides à bas nombre de copies, et des homologues de ces systèmes de partition sont présents sur la majorité des chromosomes bactériens. Le système code deux protéines, une ATPase et une protéine qui se fixe spécifiquement sur une région centromérique. Ces deux protéines interagissent entre elles, permettent la localisation subcellulaire des réplicons et assurent ainsi leur maintien dans les générations futures. Au laboratoire, nous étudions l'un des systèmes modèles majeurs, le système de partition du plasmide F d'Escherichia coli, afin de déterminer le mécanisme moléculaire assurant le processus de ségrégation et son contrôle pendant le cycle cellulaire. La stabilité du plasmide F est assurée par le système de partition sopABC. Après la réplication du plasmide, la protéine SopB s'assemble sur le centromère sopC pour former un complexe de partition qui permet aux copies du plasmide d'être positionnés au centre de la cellule. Avant la division cellulaire les plasmides migrent aux positions 1/4 et 3/4 de la cellule et assurent ainsi l'héritage des réplicons dans les futures cellules filles. L'ATPase SopA est essentielle dans le processus de partition, mais son rôle n'est pas bien défini. SopA pourrait être impliquée dans les étapes de positionnement et/ou de déplacement des plasmides de part et d'autre de la cellule. SopA possède plusieurs activités. In vivo, SopA agit comme autorépresseur de l'opéron sopAB en se fixant sur la région promotrice. De plus elle interagit avec le complexe de partition et forme des polymères en présence d'ATP. Nous avons montré que cette activité est régulée par SopB et par l'ADN. L'activité ATPase de SopA est essentielle pour la partition. Elle est légèrement stimulée par SopB et par l'ADN, mais lorsque ces deux facteurs sont présents, elle est fortement stimulée. Nous avons entrepris de caractériser les interactions existantes entre ces trois protagonistes. Ainsi, nous avons démontré que cette stimulation nécessite une interaction de SopA avec SopB d'une part et avec l'ADN d'autre part. Nous avons également montré que le site centromérique sopC potentialise la stimulation de l'activité ATPase par l'intermédiaire de SopB. Nous nous sommes intéressés ensuite à l'interaction SopA-SopB, et nous avons mis en évidence que SopB stimule l'activité ATPase de SopA via un motif arginine finger. Pour finir, nous avons montré que in vivo, la stimulation de l'activité ATPase de SopA joue un rôle dans la régulation de l'opéron sopAB mais aussi dans la partition du plasmide FMitotic segregation of chromosomes and plasmids, termed partition in bacteria, is a fundamental step of the cell cycle that ensures the transmission of the whole genome to daughter cells. It is governed by specific genetic loci named par, first identified in low copy number plasmids and later found to be present as homologues in most bacterial chromosomes. Par loci encode two proteins, an ATPase and a DNA binding protein, and include a cis-acting centromeric site. These components interact with each other to direct the subcellular localization that ensures stability of their replicons. To determine the molecular mechanisms of the partition process and its control during the cell cycle, we study the Sop partition system of the Escherichia coli plasmid, F. Sop is one of the best-known partition systems. After F plasmid replication, SopB protein binds to the sopC centromeric site to form a partition complex. The complex on each plasmid copy interacts with SopA, an ATPase, and activates it to move the plasmid molecules towards the two cell poles. SopA ATPase is essential to the segregation process but its role is not defined. SopA has many activities. In vivo it represses its own operon by binding to the sopAB promoter. Moreover, in addition to its interaction with the partition complex it polymerizes in the presence of ATP. We have shown that SopB and DNA regulate this activity. Although the ATP-binding site on SopA is essential for partition, ATP hydrolysis by SopA is very weak. It is stimulated modestly by DNA and by SopB and strongly in the presence of both. We have characterized the interactions necessary for stimulation of ATP hydrolysis. First we found that the SopB-sopC partition complex is required for maximal stimulation. Then we showed that SopB and DNA contact SopA by two distinct interactions to fully activate ATPase activity. We also found that SopB activates SopA ATPase through an arginine finger motif. Finally, we have shown that in vivo, stimulation of the ATPase activity is necessary for both regulation of the sopAB operon and partition of plasmid F to be efficient
4
Libante, Virginie. "Analyse du système SOP responsable de la partition du plasmide F chez Escherichia coli : sopA, une ATPase essentielle au mécanisme de partition." Toulouse 3, 2002. http://www.theses.fr/2002TOU30209.
Full textAbstract:
Le maintien des réplicons bactériens (partition) présente des similitudes avec la mitose eukaryote. Dans l'équipe du Dr Lane nous étudions le plasmide F d'Escherichia coli qui possède un système actif de partition. Ce dernier est très répandu parmi les réplicons bactériens. Il est composé de deux protéines, SopA et SopB produites à partir d'un opéron dont la transcription est réprimée par SopA. En aval se trouve le site sopC sur lequel SopB se fixe pour former le complexe de partition. Nous avons centrés nos recherches sur l'activité ATPase de SopA au moyen d'une mutagenèse du site actif de fixation de l'ATP. J'ai purifié ces protéines mutées et les ai caractérisées, tout en menant en parallèle une étude de leur fonction in vivo. Nous avons établi l'importance de l'activité ATPase dans la partition et dans la répression. La localisation de SopB a été déterminée au moyen d'une protéine SopB-GFP. Nous avons montré qu'elle était dépendante de SopA, sopC et du site actif ATPase de SopA.
5
Sanchez, Aurore. "La ségrégation du plasmide F d'Escherichia coli : étude des spécificités d'interaction du centromère avec la protéine SopB et organisation du complexe de partition étendu." Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2447/.
Full textAbstract:
La ségrégation du matériel génétique est une étape fondamentale du cycle cellulaire permettant la transmission du patrimoine génétique au cours des générations. Dans les cellules eucaryotes, la mitose est l'étape qui permet la répartition des chromosomes dupliqués dans chaque cellule fille. Des systèmes actifs, dédiés à la ségrégation de l'ADN sont retrouvés sur la majorité des plasmides et chromosomes bactériens. Ces systèmes ParABS, dits "de partition", sont constitués de deux protéines, ParA et ParB, et d'une séquence centromérique, parS. La protéine ParA est une ATPase capable de positionner les plasmides dans le cytoplasme tout au long du cycle cellulaire. Son comportement dynamique fait d'elle le moteur de la partition. La protéine ParB, l'autre acteur de la partition est une protéine adaptatrice entre la molécule d'ADN et la protéine motrice. ParB se fixe sur le centromère parS pour former une complexe nucléoprotéique appelée "complexe de partition". En utilisant différents modes de fixation à l'ADN et en établissant des interactions protéine-protéine multiples, ParB est aussi capable de s'organiser en complexe de partition dit "étendu" qui est le substrat de la réaction de ségrégation. La formation du complexe de partition "étendu" est la première étape du mécanisme de partition et est essentielle au processus de ségrégation. L'architecture de ce complexe n'est connue pour aucun des systèmes de partition parABS. L'un des systèmes modèles majeurs du mécanisme de ségrégation de l'ADN chez les bactéries est le système sopABC du plasmide F d'E. Coli. Ainsi, au cours de ma thèse, j'ai initié plusieurs projets en parallèle, visant à caractériser à la fois in vivo et in vitro, les différentes interactions impliquées dans l'organisation du complexe de partition et du complexe de partition "étendu" de ce plasmide. En collaboration avec l'équipe du Dr Véronique Le Berre au Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP-INSA) de Toulouse, j'ai contribué à la validation des déterminants nucléiques impliqués dans l'interaction de notre séquence centromérique modèle, parS, avec le motif hélice-tour-hélice (HTH) de ParB. Ensuite, nous avons identifié un nouveau motif en dehors du motif HTH et montré qu'une arginine de ce motif est essentielle à l'interaction spécifique avec le centromère. Ces résultats ont révélé une caractéristique conservée dans le règne bactérien : les protéines ParB contiennent un domaine de liaison au centromère, composé de deux motifs séparés et essentiels. Le cœur de mes travaux de thèse a été de comprendre l'organisation du complexe de partition "étendu" et son rôle dans la partition. Par une combinaison d'approche moléculaire in vivo et in vitro, j'ai montré que l'architecture de ce complexe étendu en dehors des sites parS, nécessitait deux types d'interaction, des interactions protéine/protéine mais également ADN/protéine. Afin d'étudier le mode d'interaction de ParB avec des séquences nucléiques non spécifiques avoisinant le complexe de partition, j'ai mis en œuvre une technique d'immunoprécipitation de chromatine, couplée à des techniques de hautes détections (qPCR ou ChIPseq). Cette technique nous a permis de montrer que ParB est capable de s'étendre sur une distance d'environ vingt kilobases de part et d'autre du centromère. Nos résultats semblent incompatibles avec le précédent modèle dans lequel ParB serait capable de polymériser sur l'ADN, à la manière d'un protéo-nucléofilament qui s'initierait au niveau du centromère. Ainsi ces travaux, nous ont permis de proposer un nouveau modèle dans lequel le complexe de partition "étendu" serait une structure concentrée, dynamique et résultant d'interactions stochastiques entre ParB et l'ADN avoisinant ParSSegregation of genetic material over generations is an essential process ensuring that every daughter cell receives a copy of each DNA molecule. Similarly to Eukaryotes, Prokaryotes possess cytoskeletal machineries, named Par, responsible for DNA segregation. Bacterial Par systems, found on chromosomes as well as on various low copy number plasmids, are composed of three elements: a ParA protein, a ParB protein and a centromere site, parS. ParA ATPase is able to position plasmids in the cytoplasm during the cell cycle. Its dynamic pattern make it the motor of the partition. The centromere binding protein (CBP) ParB, binds the centromere to form a nucleoprotein assembly called the "partition complex". Using different mode of DNA binding and multiple protein-protein interactions, ParB is also capable of organizing into higher order complexes called the "extended" partition complex. This complex is the substrate for the partitioning process. Formation of the extended partition represents the first step in partition and is essential to segregation. The architecture of this complex is not known for any partition system parABS. Here, we focus on the assembly of the F partition complex. During my PhD, I initiated several projects in parallel to characterize the different interactions involved in the organization of the partition complex and the extended partition complex of this plasmid with in vivo and in vitro approaches. In collaboration with the laboratory of Dr. Veronique Le Berre in Toulouse (LISBP -INSA), we determined sopC basis involved in specific SopB-sopC interactions. Then, we identified a new ParB determinant, outside of the helix-turn-helix DNA binding motif, responsible for specific DNA binding to the centromere. These findings reveal that ParB have an extended DNA binding domain, composed of two separate DNA binding motifs. We extended our analysis to chromosomal ParB and show that this second centromere binding motif is highly conserved in a wide range of bacteria. Using in vivo and in vitro approaches, we show that the extended partition complex architecture requires both protein-protein and protein-DNA interactions. To investigate the overall organization of the SopB-sopC extended partition complex, we use chromatin immunoprecipitation (ChIP) coupled with high throughput sequencing. This technique allowed us to visualize that SopB is able to extend around sopC over ~20 Kb. Our results are thus inconsistent with previous models suggesting that SopB polymerize side by side in a proteo-nucleofilament emanating from the centromere. So, we propose a new model in which the extended partition complex of F plasmid assembles in a nucleoprotein complex from stochastic binding of SopB on neighboring sopC DNA
6
Castaing, Jean-Philippe. "La ségrégation du plasmide F d'Escherichia coli : étude du rôle de la fixation de l'ATPase Sopa à l'ADN." Toulouse 3, 2009. http://thesesups.ups-tlse.fr/597/.
Full textAbstract:
La ségrégation de l'ADN, appelée partition chez les procaryotes, permet à tout organisme de transmettre son patrimoine génétique au cours des générations. Il existe des systèmes actifs de partition présents sur la majorité des plasmides et des chromosomes bactériens. Ces systèmes sont essentiels pour la ségrégation active des plasmides à bas nombre de copies tel que le plasmide F d'Escherichia coli, étudié au sein de notre équipe. Son système de partition, appelé sop, est composé de deux gènes, sopA et sopB et d'une séquence centromérique sopC. SopB se fixe à sopC pour former le complexe de partition, reconnu par l'ATPase SopA. SopA polymérise en présence d'ATP. Ce comportement pourrait être le " moteur " de la ségrégation des réplicons. Les travaux de notre équipe ont démontré que SopA se fixe de manière ATP-dépendante à l'ADN non spécifique. Cette fixation inhibe la polymérisation de SopA. SopB, de par sa capacité à se fixer à l'ADN non spécifique, contrebalance ainsi cette inhibition. Nous proposons un modèle dans lequel la polymérisation de SopA serait régulée dans la cellule par l'ADN du nucléoïde. En présence du plasmide, SopB, présent à forte concentration autour du complexe de partition, masquerait l'ADN, créant un environnement dans lequel SopA initierait sa polymérisation. Cette régulation de la dynamique de SopA serait nécessaire au processus de partition. Afin d'étayer notre modèle, nous avons recherché un domaine d'interaction à l'ADN dans SopA. Nous avons identifié un mutant ayant perdu sa fixation ATP-dépendante à l'ADN. Seules les activités de SopA dépendante de cette reconnaissance de l'ADN ont été affectées : l'inhibition de la polymérisation, la stimulation de l'activité ATPase basale et la localisation intracellulaire. Cette mutation entraîne aussi une perte majeure de stabilité du plasmide F correspondant. Ceci confirme l'implication de l'ADN du nucléoïde dans la régulation du comportement dynamique de SopA nécessaire à la partition du plasmide FThe segregation of the DNA, also called partition for procaryotes, is the process allowing any organisms to transmit its genetic heritage to next generation. In bacteria, mitotic stability of plasmids and many chromosomes depends on replicon-specific systems which comprise a centromere, a centromere-binding protein and an ATPase. We have taken as a model, the low-copy number plasmid F of Escherichia coli. Centromere-binding protein SopB binds to sopC centromere and forms the partition complex. This nucleoproteic complex is recognized by the SopA "Walker-box" ATPase. SopA shares with other partition ATPase the capacity of self assembly in presence of ATP. This dynamic self-assembly would allow active partition during bacterial division. Previous work in our team showed SopA is also able to bind to non specific DNA in an ATP-dependant manner whereby polymerization is inhibited. Indeed, DNA inhibited this polymerization and cause breakdown of pre-formed polymers. SopB counteracted this DNA effect by binding itself to and masking DNA. We had proposed a model in which the polymerization is spacially regulated. Nucleoid DNA prevent inappropriate SopA polymerization but when SopB is present in high concentration, it create a DNA-depleted zone within SopA can initiate polymerization. The regulation of the dynamic behaviour of the "driving" protein of the system would be necessary for the process of partition. To support our model, we looked for a DNA binding domain in SopA. We have found a SopA mutant, defective for ATP dependent DNA binding. Only the activities of SopA dependent on this binding were affected: the inhibition of the polymerisation is abolished, as the stimulation of the ATPase activity and the intracellular localization. Moreover, this mutant is defective for plasmid stabilization. This last result confirms the implication of the nucleoïd DNA in regulation of the dynamic behavior of SopA, which is necessary for the partition of the plasmide F
7
Thüne, Mario. "Eigenvalues of Matrices and Graphs." Doctoral thesis, Universitätsbibliothek Leipzig, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-120713.
Full textAbstract:
The interplay between spectrum and structure of graphs is the recurring theme of the three more or less independent chapters of this thesis.
The first chapter provides a method to relate the eigensolutions of two matrices, one being the principal submatrix of the other, via an arbitrary annihilating polynomial. This is extended to lambda-matrices and to matrices the entries of which are rational functions in one variable. The extension may be interpreted as a possible generalization of other known techniques which aim at reducing the size of a matrix while preserving the spectral information. Several aspects of an application in order to reduce the computational costs of ordinary eigenvalue problems are discussed.
The second chapter considers the straightforward extension of the well known concept of equitable partitions to weighted graphs, i.e. complex matrices. It provides a method to divide the eigenproblem into smaller parts corresponding to the front divisor and its complementary factor in an easy and stable way with complexity which is only quadratic in matrix size. The exploitation of several equitable partitions ordered by refinement is discussed and a suggestion is made that preserves hermiticity if present. Some generalizations of equitable partitions are considered and a basic procedure for finding an equitable partition of complex matrices is given.
The third chapter deals with isospectral and unitary equivalent graphs. It introduces a construction for unitary equivalent graphs which contains the well known GM-switching as a special case. It also considers an algebra of graph matrices generated by the adjacency matrix that corresponds to the 1-dimensional Weisfeiler-Lehman stabilizer in a way that mimics the correspondence of the coherent closure and the 2-dimensional Weisfeiler-Lehman stabilizer. The algebra contains the degree matrix, the (combinatorial, signless and normalized) Laplacian and the Seidel matrix. An easy construction produces graph pairs that are simultaneously unitary equivalent w.r.t. that algebra.
8
Filosa, Damien. "Les égalités du partage : de l'égalité du partage, à l'égalité par le partage." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0708.
Full textAbstract:
Le droit au partage est généralement présenté comme étant consubstantiel du droit de propriété. Ce dernier est garanti par des textes de valeur constitutionnelle. Or, sinon le caractère prétendument absolu du droit de propriété, du moins son rang dans la hiérarchie des droits réels, s'opposent à ce que ses titulaires se trouvent contraints de l’exercer selon des modalités non voulues. Il importe dès lors que l'opération de partage soit impérativement réalisée dans le respect du droit dont elle est le prolongement, c'est-à-dire conformément aux intérêts patrimoniaux des copartageants. C'est « l’égalité » du partage, entendue alors comme synonyme de neutralité économique de l’opération. Mais les relations entre égalité et partage excèdent largement la notion d'égalité face à l'opération de « conversion » que réalise le partage. L'égalité n'est pas seulement le critère et l'impératif du partage ; elle en est aussi la « cause-impulsive », et parfois le motif. En certaines occasions, c'est parce qu'une certaine forme d'égalité aura été voulue qu'un partage s'établira. A cet égard, l’égalité ne se borne alors plus à assurer la bonne fin du partage ; elle le suscite. Le partage ne saurait se réduire en effet à la simple réalisation d’une opération commutative. Il assure la réception, en droit privé et, plus particulièrement, au sein du droit patrimonial de la famille, d’une aspiration égalitaire transcendant la technique juridique. La convention de partage n’est pas seulement un contrat nécessairement « égalitaire » ; elle emporte « contractualisation de l’égalité ». L’égalité en constitue le principal objetThe right to an equal share in the partition / to equal partition is undisociable from the right to property which is garanteed by Constitutional law. So, If not because of the allegedly absolute right to property, at least because of its rank in the hierarchy of real rights, the right to division is contrary to any acceptance by the entitled (of the proceedings) on undesired modalities. This is equality in partition in the full sense of the word – a synonym, here, of economic neutrality of the operation. The relations between equality and partition go beyond the notion of equality as understood in partition proper. Equality, indeed, is not solely the criterium and imperative for the partition, it is also the cause and, at times, even, the mobile. It may happen that partitioning is made because a certain kind of equality is desired. In these cases, equality has not its goal limited in bringing about a partition; but partition finds its cause in equality. It can, thus, be said that partitioning sums up both the efficacy of the right to property and the enforcement of a principle of equality that far exceeds its legal technique. It is clear, indeed, that the partition can’t be reduced to the sole effectiveness of a necessarily accumulative operation. It helps acknowledge, within, the private law and the patrimonial family law, in particular, that aspiration for equality that far transcends legal procedures. In that sense, the partition agreement must not be regarded solely as a necessarily egalitarian contract; it entails that equality itself be a contract. Indeed, equality is not a characteristic of the operation but its main object
9
David, Ariane. "Chorégraphie de ségrégation des deux chromosomes de Vibrio cholerae." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00921394.
Full textAbstract:
L'objectif de cette thèse est de définir la chorégraphie de ségrégation des deux chromosomes circulaires de Vibrio cholerae, c'est à dire le positionnement de l'information génétique au cours de la croissance de la cellule, ainsi que les mécanismes dirigeant ces ségrégations. Il a longtemps été supposé que les bactéries étaient trop petites pour avoir une organisation intra-cellulaire, et le manque de techniques appropriées ne permettait pas d'infirmer cette hypothèse. Or la taille des chromosomes comparée à celle de la bactérie impose une compaction et aujourd'hui, de nouvelles techniques de microscopie et d'analyse génétique permettent d'affirmer que les chromosomes bactériens étudiés jusqu'à maintenant ont tous une organisation et une chorégraphie de ségrégation précises et différentes selon les espèces. Toutes les espèces étudiées à ce jour ont un chromosome circulaire unique : la réplication du chromosome commence à une origine unique bidirectionnelle, les deux fourches de réplication se déplacent le long des deux bras de réplication (ou réplichores) et finissent la réplication au terminus, diamétralement à l'opposée de l'origine de réplication sur la carte du chromosome. Peu d'espèces ont été étudiées, et Vibrio cholerae émerge progressivement comme un nouveau modèle : son génome est réparti sur deux chromosomes, et la chorégraphie de plusieurs chromosomes dans une cellule n'a jamais été décrite. De plus, cette espèce semble être au croisement évolutif entre Caulobacter crescentus et Escherichia coli : Vibrio cholerae a d'une part une morphologie en croissant, des systèmes de partition aux origines et un positionnement de l'origine du chromosome I, semblables à C. crescentus, et d'autre part un système de compaction du terminus et un set de gènes impliqués dans la maintenance du chromosome ayant co-évolué, qu'on ne retrouve que dans peu d'espèces proches d'E. coli. Une autre caractéristique intéressante de V. cholerae est que le chromosome II semble avoir été acquis récemment et n'est donc peut être pas gouverné par les mêmes mécanismes que le chromosome I, comme en témoignent le positionnement de son origine et son terminus, inédits pour des chromosomes bactériens. Parmi les Vibrios (environ 60 espèces principalement retrouvées dans les environnements aquatiques), certaines espèces sont des pathogènes dévastateurs pour les poissons, le corail, les crustacés ou les fruits de mer. Mais la plus documentée est Vibrio cholerae, car elle provoque chez l'Humain une maladie provoquée par l'ingestion d'eau contaminée qui peut être mortelle si le patient n'est pas réhydraté à temps. Bien que facilement traitable, le choléra fait encore de nombreuses victimes dans les pays en développement où les structures de santé et les règles d'hygiène font parfois défaut. Ainsi l'étude de Vibrio cholerae présente un intérêt médical, mais également par extension aux autres Vibrios, un intérêt environnemental non négligeable.
10
Stewart, Derek George. "Changes in the tri-partite relationship between central government, local government and civil society and its implications for the geography of the city : the effects of developments in public education management on school catchments in the Glasgow division of the former Strathclyde region 1990-96." Thesis, University of Glasgow, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298686.
Full textBooks on the topic "Partitive Division"
3
Carmen Pérez de Ontiveros Baquero. División de la comunidad de bienes y exclusión de la acción de división. Cizur Menor (Navarra): Thomson Reuters Aranzadi, 2014.
Find full text
5
Allue, Fernando Crespo. La división de la comunidad de bienes. Valladolid: Editorial Lex Nova, 1993.
Find full text
6
Celso Laet de Toledo Cesar. Venda e divisão da propriedade comum. 3rd ed. São Paulo, SP, Brasil: Editora Revista dos Tribunais, 2006.
Find full text
7
Minervini, Enrico. Divisione contrattuale ed atti equiparati. Napoli: Edizioni scientifiche italiane, 1990.
Find full text
8
Terras particulares: Demarcação, divisão, tapumes. 5th ed. São Paulo, SP: Editora Saraiva, 2009.
Find full text
9
Júnior, Humberto Theodoro. Terras particulares: Demarcação, divisão, tapumes. 5th ed. São Paulo, SP: Editora Saraiva, 2009.
Find full text
10
Depuy, Laurent. La superposition des divisions juridiques de l'immeuble: Ouvrage honoré du prix de thèse de la Chambre des notaires. La Baule: Mouette, 2001.
Find full textBook chapters on the topic "Partitive Division"
1
Jiang, Yun, and Zhiqiang Chen. "Uniform Solution to Partition Problem Using P Systems with Membrane Division." In Communications in Computer and Information Science, 204–10. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-662-45049-9_33.
Full text
2
Wang, Lin, Bo Yang, Zhenxiang Chen, Ajith Abraham, and Lizhi Peng. "A Novel Improvement of Neural Network Classification Using Further Division of Partition Space." In Bio-inspired Modeling of Cognitive Tasks, 214–23. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-73053-8_21.
Full text
3
Nathanson, Melvyn B. "Trapezoidal Numbers, Divisor Functions, and a Partition Theorem of Sylvester." In Analytic Number Theory, Modular Forms and q-Hypergeometric Series, 555–86. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-68376-8_31.
Full text
4
Padrón, Miguel A., and Ángel Plaza. "The 8T-LE Partition Applied to the Barycentric Division of a 3-D Cube." In Lecture Notes in Computational Science and Engineering, 753–62. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-55874-1_74.
Full text
5
"Characterizing Pareto Optimality II: Partition Ratios." In The Geometry of Efficient Fair Division, 190–219. Cambridge University Press, 2005. http://dx.doi.org/10.1017/cbo9780511546679.009.
Full text
6
"Other Issues Involving Weller's Construction, Partition Ratios, and Pareto Optimality." In The Geometry of Efficient Fair Division, 352–84. Cambridge University Press, 2005. http://dx.doi.org/10.1017/cbo9780511546679.014.
Full text
7
Yusin, Jennifer. "Whither Partition?" In The Future Life of Trauma. Fordham University Press, 2017. http://dx.doi.org/10.5422/fordham/9780823275458.003.0004.
Full textAbstract:
This division constructs a dialogue between the materiality of trauma and the postcolonial condition through a sustained focus on the establishment of new geographical borders during the 1947 Partition of British India. The border is treated as an assigned place without proper destination. The chapter pays particular attention to the ways in which the temporality and formation of forms of nation during the Partition situate the living being and subject as the center of interaction to the extent it challenges the western tradition’s ideological tendency to assume life as irremediably divided between its symbolic and empirical, material aspects. The case of the Partition makes clear that the event as it is governed by the axiological principle of the “always already” in the psychoanalytic conception of trauma is overcome by the emergence of partition as another regime of events that asserts a coincidence between the material and symbolic domains of life.
8
Shelef, Nadav G. "Italy’s Forgotten Partition." In Homelands, 80–107. Cornell University Press, 2020. http://dx.doi.org/10.7591/cornell/9780801453489.003.0004.
Full textAbstract:
This chapter analyzes the division of Venezia Giulia, a paradigmatic case in which the partition of homeland territory in the aftermath of war came to be accepted as appropriate by those on both sides of the border. At the end of World War II, American intelligence services identified the border between Italy and Yugoslavia as particularly problematic and as a likely location for violent confrontations between East and West. Alongside the raging international conflict of the Second World War, this border zone was the site of an ethnic civil war between Slavs and Italians that was as bloody and bitter as any other. Yet, by the 1970s, this region became a model for regional cooperation. While individual claims for compensation for lost property remain, mainstream Italian nationalists no longer claim the areas they once fought for so passionately as appropriately part of their homeland. The chapter argues that this acceptance was not automatic or inevitable. Rather, the efforts of the governing Christian Democracy Party (DC) to stem additional territorial losses after the war and to overcome the short-term political challenges it faced in the new republic shaped the timing and process of the withdrawal of homeland territoriality from once-sacred land.
9
Garvan, F. G. "Weighted Partition Identities and Divisor Sums." In Frontiers in Orthogonal Polynomials and q-Series, 239–49. WORLD SCIENTIFIC, 2018. http://dx.doi.org/10.1142/9789813228887_0012.
Full text
10
"Appendix 2: A Second Tri-partite Division of the Soul?" In Why Plato Wrote, 155–57. Oxford, UK: Blackwell Publishing Ltd., 2012. http://dx.doi.org/10.1002/9781118556696.app2.
Full textConference papers on the topic "Partitive Division"
1
Heath, Amanda Lake, and L. Jeneva Clark. "Problem posing in partitive and quotitive division." In 42nd Meeting of the North American Chapter of the International Group for the Psychology of Mathematics Education. PMENA, 2020. http://dx.doi.org/10.51272/pmena.42.2020-227.
Full text
2
Oda, Tomohiro, Yasuhito Fujisawa, and Mitsutoshi Watanabe. "Experimental Study on Sound Insulation Performance of Partition Walls Joined to Steel Beams." In ASME 2018 Noise Control and Acoustics Division Session presented at INTERNOISE 2018. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/ncad2018-6122.
Full textAbstract:
An experimental study was conducted to confirm the sound insulation performance of a partition wall that was joined to a steel beam. Fireproofing protections, such as sprayed rock wool, are used to protect steel members from heat in the case of fire. However, the influence of transmitted sound from steel members with fireproofing protections and from joints of the partition wall and steel members has not been quantitatively investigated. Therefore, the sound transmission loss was measured using specimens that consisted of a partition wall and a steel beam, which was coated with sprayed rock wool. The results showed that the sound transmission loss of the specimen was lower than that of the partition wall element. It was inferred that the mass-spring-mass resonance of the fireproofing protections on the steel web reduced the sound insulation performance of the specimen. Moreover, the influence of the transmitted sound from the steel web was greater than that from the joints of the partition wall and the steel beam. In addition, when the gypsum board was added to the specimen as a ceiling, it was confirmed that the sound insulation performance of the specimens was equal to that of the partition wall element.
3
Sagers, Jason, Jonathan D. Blotter, and Timothy W. Leishman. "Active Sound Transmission Control of an Experimental Double-Panel Partition Using Decoupled Analog Feedback Control." In ASME 2008 Noise Control and Acoustics Division Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/ncad2008-73018.
Full textAbstract:
This paper addresses the construction, measurement, and analysis of a double-panel active partition (DPAP) and its accompanying analog feedback controllers. The DPAP was constructed by attaching an aluminum cone loudspeaker at each end of a short segment of a circular duct. Two analog feedback controllers were designed and built using the measured frequency response function of each panel. Two independent (decoupled) feedback controllers were then used to minimize the vibration amplitude of each panel in the presence of an acoustic disturbance. A normal-incidence transmission loss measurement system was used to assess the performance of the DPAP and of a single panel passive partition. Error signal attenuations show that it is both feasible and effective to simultaneously control both panels with decoupled feedback controllers, and that simultaneously controlling both panels of the DPAP has a distinct advantage over controlling a single panel. The reduction in vibration amplitude across the surface of the transmitting panel was confirmed with scanning laser vibrometer measurements. Transmission loss results were obtained for two passive and three active configurations. The average normal incidence transmission loss over the active measurement bandwidth (50–1,000 Hz) for the active double-panel was 60 dB. This is an average of 39 dB more transmission loss than a passive single panel partition.
4
Biswas, Arpita, and Siddharth Barman. "Fair Division Under Cardinality Constraints." In Twenty-Seventh International Joint Conference on Artificial Intelligence {IJCAI-18}. California: International Joint Conferences on Artificial Intelligence Organization, 2018. http://dx.doi.org/10.24963/ijcai.2018/13.
Full textAbstract:
We consider the problem of fairly allocating indivisible goods, among agents, under cardinality constraints and additive valuations. In this setting, we are given a partition of the entire set of goods---i.e., the goods are categorized---and a limit is specified on the number of goods that can be allocated from each category to any agent. The objective here is to find a fair allocation in which the subset of goods assigned to any agent satisfies the given cardinality constraints. This problem naturally captures a number of resource-allocation applications, and is a generalization of the well-studied unconstrained fair division problem. The two central notions of fairness, in the context of fair division of indivisible goods, are envy freeness up to one good (EF1) and the (approximate) maximin share guarantee (MMS). We show that the existence and algorithmic guarantees established for these solution concepts in the unconstrained setting can essentially be achieved under cardinality constraints. Furthermore, focusing on the case wherein all the agents have the same additive valuation, we establish that EF1 allocations exist even under matroid constraints.
5
Wen Xi, Wen Xi, Xiaopeng Yang Xiaopeng Yang, Yuze Sun Yuze Sun, and Tao Zeng Tao Zeng. "Subarray partition method based on division position coding genetic algorithm." In IET International Radar Conference 2015. Institution of Engineering and Technology, 2015. http://dx.doi.org/10.1049/cp.2015.1484.
Full text
6
Gilles, Philippe, Yann Andrieu, and Claude Amzallag. "Comparison Between J and Collapse Load Approaches Applied to Fracture Test Results on Ni Base Alloy 600 Surface Cracked Plates." In ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-25708.
Full textAbstract:
The paper presents a fracture mechanics analyses of CT and surface cracked plate specimens (CCT) made from material Inconel 600. The main issue is to determine whether the plates fracture by ductile tearing or collapse with the aim of determining a simplified fracture assessment of steam generator partition plates. The paper compares J based analyses to several collapse load formulae. It is shown that estimating the tearing initiation load is almost unachievable in the present tests designed as demonstrative tests. It is also proven that most of the case collapse load formulae are very conservative. The results contribute to evidence that partition plates exhibit sufficient safety margins to failure up to the end of service life in spite of the presence of a very deep initial crack.
7
Gardner, Christopher, Rajeev Madazhy, and Erik Howard. "Analysis of Contact Pressure Distribution on a Pass Partition Gasket in Conjunction With a Double-Tapered Seal in a High Pressure Heat Exchanger Closure." In ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-26157.
Full textAbstract:
This paper describes the use of a partition gasket in addition to a self-energized, double-tapered, metal seal in a high pressure heat exchanger. For over 30 years a single gasket was used to seal the heat exchanger partitions against the closure. Although designed to standard code, it often resulted in leaks. Over the past five years, the double-tapered seal has been used extensively to replace welded diaphragms in high pressure heat exchangers in refineries with great success. In this design a tapered-seal is introduced in conjunction with a pass partition gasket for multiple pass heat exchanger, to address problems associated with leaks. Finite Element Analysis (FEA) was performed on the assembly at bolt-up and during internal pressure operation, and contact pressure distribution was analyzed. A 12″ scaled model of the actual heat exchanger closure assembly was designed and hydrostatic pressure tested to ensure relative pressures were held. Actual working-plant applications will be discussed as well.
8
Kruntcheva, Mariana R. "Passive Noise Reduction in an Automotive Compartment." In ASME 2008 Noise Control and Acoustics Division Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/ncad2008-73073.
Full textAbstract:
Fuel economy, international competition and socioeconomic factors have forced manufacturers to develop lighter automotive vehicles. However, such vehicles are typically more susceptible to noise and vibration problems. The internal sound field in the passenger compartment is affected significantly by the acoustic modal characteristics of the cavity, by the dynamic behaviour of the surrounding structure, and by the nature of the coupling of these two dynamic systems. The purpose of this research is to develop and analyse a new vibroacoustic model containing the main compartment cavity and the luggage compartment cavity. Special attention is placed on the effect of a double walled partition between the main compartment cavity and the luggage compartment. The system is studied using ANSYS finite element (FE) code. The modelling involved shell finite elements for the structure and three-dimensional (3D) acoustic elements for the cavities. The 3D FE modal analysis produced results visualizing the complex picture of acoustic-structure coupling in the lower frequency range (30–200 Hz). It was found that strong coupling between the thin walled structure and the acoustic enclosures exists in the vicinity of any acoustic resonance. The key noise reduction principle examined is the passive application of a characteristic impedance mismatch. Using an FE model, numerical simulations are conducted to study the effect of various design parameters on acoustic transmission. The results show that at least 8 dB reductions in sound pressure level may be achieved with a modest level of vacuum in the double partition between the main cabin and the luggage compartment cavity.
9
Kobayashi, Katsutoshi, Isao Hagiya, Hideki Akiniwa, Hiroaki Yoda, and Daijirou Senba. "Development of Double Suction Volute Pump for High Efficiency." In ASME 2013 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/fedsm2013-16345.
Full textAbstract:
The double suction volute pump consists of three components: a double suction flow path in upstream, an impeller with five blades, and a double volute flow path in downstream. The double suction was designed to improve a flow on the inlet surface of impeller. A significantly high pre-swirl velocity and low pre-swirl velocity were observed in original double suction, however its high pre-swirl velocity was slowed down and its low pre-swirl velocity was speeded up in designed double suction. As a result, the designed double suction had a more uniform velocity distribution on the inlet surface of impeller. The impeller had twenty design parameters and those parameters were optimized by genetic algorithm (GA) to improve the impeller efficiency. A high total pressure loss was observed on the outlet surface of impeller and near the shroud wall of impeller meridian surface. On the other hand, its total pressure loss was decreased in optimized impeller, and the impeller efficiency increased by +0.7[%]. The cross-sectional surfaces, which were defined on a main streamwise curve of double volute, were designed to decrease a total pressure loss occurring inside double volute. In designed double volute, a secondary vortex on the cross-sectional surface was suppressed and a high circumferential velocity was decreased near the tongue and front edge of partition wall. As a result, the total pressure loss was decreased inside designed double volute. The hydraulic pump performance for designed pump, which consisted of the designed double suction, optimized impeller and designed double volute, was predicted by numerical simulation. Efficiencies in double suction, impeller and double volute were increased by 0.6[%], 0.4[%] and 1.1[%] respectively and the total improvement of pump efficiency was 1.9[%]. The designed pump was manufactured and its hydraulic performance was measured by experiment. The numerical results of pump efficiency agreed well with experimental ones. The efficiency of designed pump increased by 2.0[%] compared with that of original pump in experiment.
10
Corcoran, Joseph M., Marcel C. Remillieux, and Ricardo A. Burdisso. "Prediction of High Frequency Sonic Boom Noise Transmission Into Buildings Using a Hybrid Analytical-Ray Tracing Approach." In ASME 2012 Noise Control and Acoustics Division Conference at InterNoise 2012. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ncad2012-0955.
Full textAbstract:
As part of the effort to renew commercial supersonic flight, a predictive numerical tool to compute sonic boom transmission into buildings is under development. Due to the computational limitations of typical numerical methods used at low frequencies (e.g. Finite Element Method), it is necessary to develop a separate approach for the calculation of acoustic transmission and interior radiation at high frequencies. The high frequency approach can then later be combined with a low frequency method to obtain full frequency vibro-acoustic responses of buildings. An analytical method used for the computation of high frequency acoustic transmission through typical building partitions is presented in this paper. Each partition is taken in isolation and assumed to be infinite in dimension. Using the fact that a sonic boom generated far from the structure will approximate plane wave incidence, efficient analytical solutions for the vibration and acoustic radiation of different types of partitions are developed. This is linked to a commercial ray tracing code to compute the high frequency interior acoustic response and for auralization of transmitted sonic booms. Acoustic and vibration results of this high frequency tool are compared to experimental data for a few example cases demonstrating its efficiency and accuracy.