155 research outputs found

    On the path partition of graphs

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    Let GG be a graph of order nn. The maximum and minimum degree of GG are denoted by Δ\Delta and δ\delta respectively. The \emph{path partition number} μ(G)\mu (G) of a graph GG is the minimum number of paths needed to partition the vertices of GG. Magnant, Wang and Yuan conjectured that μ(G)max{nδ+1,(Δδ)n(Δ+δ)}.\mu (G)\leq \max \left \{ \frac{n}{\delta +1}, \frac{\left( \Delta -\delta \right) n}{\left( \Delta +\delta \right) }\right \} . In this work, we give a positive answer to this conjecture, for Δ2δ \Delta \geq 2 \delta .\medskip \end{abstract}Comment: 13 pages,3 figure

    On the existence of a matching orthogonal to a 2-factorization

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    AbstractThis note gives a partial answer to a problem posed by Brian Alspach in a recent issue of Discrete Mathematics. We show that if F1, F2,…,Fd is a 2-factorization of a 2d-regular graph G of order n⩾3.23d then G contains a d-matching with exactly one edge from each of F1, F2,…,Fd

    Revising the Metacognitive Awareness of Reading Strategies Inventory (MARSI) and testing for factorial invariance

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    In this study, we revised the Metacognitive Awareness of Reading Strategies Inventory (MARSI), a self-report instrument designed to assess students’ awareness of reading strategies when reading school-related materials. We collected evidence of structural, generalizability, and external aspects of validity for the revised inventory (MARSI-R). We first conducted a confirmatory factor analysis of the MARSI instrument, which resulted in the reduction of the number of strategy statements from 30 to 15. We then tested MARSI-R for factorial invariance across gender and ethnic groups and found that there is a uniformity in student interpretation of the reading strategy statements across these groups, thus allowing for their comparison on levels of metacognitive processing skills. We found evidence of the external validity aspect of MARSI-R data through correlations of such data with a measure of the students’ perceived reading ability. Given that this journal is oriented to second language learning and teaching, our article also includes comments on the Survey of Reading Strategies (SORS), which was based on the original MARSI and was designed to assess adolescents’ and adults’ metacognitive awareness and perceived use of ESL reading strategies. We provide a copy of the MARSI-R instrument and discuss the implications of the study’s findings in light of new and emerging insights relative to assessing students’ metacognitive awareness and perceived use of reading strategies

    Revising the Metacognitive Awareness of Reading Strategies Inventory (MARSI) and Testing for Factorial Invariance

    Get PDF
    In this study, we revised the Metacognitive Awareness of Reading Strategies Inventory (MARSI), a self-report instrument designed to assess students’ awareness of reading strategies when reading school-related materials. We collected evidence of structural, generalizability, and external aspects of validity for the revised inventory (MARSI-R). We first conducted a confirmatory factor analysis of the MARSI instrument, which resulted in the reduction of the number of strategy statements from 30 to 15. We then tested MARSI-R for factorial invariance across gender and ethnic groups and found that there is a uniformity in student interpretation of the reading strategy statements across these groups, thus allowing for their comparison on levels of metacognitive processing skills. We found evidence of the external validity aspect of MARSI-R data through correlations of such data with a measure of the students’ perceived reading ability. Given that this journal is oriented to second language learning and teaching, our article also includes comments on the Survey of Reading Strategies (SORS), which was based on the original MARSI and was designed to assess adolescents’ and adults’ metacognitive awareness and perceived use of ESL reading strategies. We provide a copy of the MARSI-R instrument and discuss the implications of the study’s findings in light of new and emerging insights relative to assessing students’ metacognitive awareness and perceived use of reading strategies

    Numerical analysis of the elastic-plastic behavior of a tubular structure in FGM under pressure and defect presence

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    Given the field of application and the many advantages, the use of FGM (Functionally Graded Materials) materials has recently been extended in several components and more particularly in cylindrical structures, which have been the subject of several recent studies. Our work aims to use the finite element method to analyze a cylindrical structure in FGM with properties gradated in the direction of the radius (Thickness) solicited purely in internal pressure by the implementation of a UMAT subroutine in the calculation code ABAQUS. The elasto-plastic behavior of the FGM is described by the flow theory represented by the equivalent stress of Von Mises and an incremental hardening variable. The TTO model (Tamura-Tomota-Ozawa) was used only to determine the elastic-plastic properties of the FGM material. The radial, tangential and axial stresses according to the thickness were evaluated in the first part of our work. In the second part, these stresses are evaluated under the same conditions but with the presence of a micro-cavity. The results obtained show clearly that these stresses are in direct relation not only with the thickness and properties of the FGM tube but also with the presence of the cavity

    Infants ask for help when they know they don’t know

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    Uncertainty monitoring is a core property of metacognition, allowing individuals to adapt their decision-making strategies depending on the state of their knowledge. Although it has been argued that other animals share these metacognitive abilities, only humans seem to possess the ability to explicitly communicate their own uncertainty to others. It remains unknown whether this capacity is present early in development, or whether it emerges later with the ability to verbally report one’s own mental states. Here, using a nonverbal memory-monitoring paradigm, we show that 20-month-olds can monitor and report their own uncertainty. Infants had to remember the location of a hidden toy before pointing to indicate where they wanted to recover it. In an experimental group, infants were given the possibility to ask for help through nonverbal communication when they had forgotten the toy location. Compared with a control group in which infants had no other option but to decide by themselves, infants given the opportunity to ask for help used this option strategically to improve their performance. Asking for help was used selectively to avoid making errors and to decline difficult choices. These results demonstrate that infants are able to successfully monitor their own uncertainty and share this information with others to fulfill their goals

    Subliminal Semantic Priming in Speech

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    Numerous studies have reported subliminal repetition and semantic priming in the visual modality. We transferred this paradigm to the auditory modality. Prime awareness was manipulated by a reduction of sound intensity level. Uncategorized prime words (according to a post-test) were followed by semantically related, unrelated, or repeated target words (presented without intensity reduction) and participants performed a lexical decision task (LDT). Participants with slower reaction times in the LDT showed semantic priming (faster reaction times for semantically related compared to unrelated targets) and negative repetition priming (slower reaction times for repeated compared to semantically related targets). This is the first report of semantic priming in the auditory modality without conscious categorization of the prime
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