631 research outputs found

    Equitable coloring of planar graphs with maximum degree at least eight

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    The Chen-Lih-Wu Conjecture states that each connected graph with maximum degree Δ≥3\Delta\geq 3 that is not the complete graph KΔ+1K_{\Delta+1} or the complete bipartite graph KΔ,ΔK_{\Delta,\Delta} admits an equitable coloring with Δ\Delta colors. For planar graphs, the conjecture has been confirmed for Δ≥13\Delta\geq 13 by Yap and Zhang and for 9≤Δ≤129\leq \Delta\leq 12 by Nakprasit. In this paper, we present a proof that confirms the conjecture for graphs embeddable into a surface with non-negative Euler characteristic with maximum degree Δ≥9\Delta\geq 9 and for planar graphs with maximum degree Δ≥8\Delta\geq 8.Comment: 19 pages, 3 figure

    A High-Performance Triple Patterning Layout Decomposer with Balanced Density

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    Triple patterning lithography (TPL) has received more and more attentions from industry as one of the leading candidate for 14nm/11nm nodes. In this paper, we propose a high performance layout decomposer for TPL. Density balancing is seamlessly integrated into all key steps in our TPL layout decomposition, including density-balanced semi-definite programming (SDP), density-based mapping, and density-balanced graph simplification. Our new TPL decomposer can obtain high performance even compared to previous state-of-the-art layout decomposers which are not balanced-density aware, e.g., by Yu et al. (ICCAD'11), Fang et al. (DAC'12), and Kuang et al. (DAC'13). Furthermore, the balanced-density version of our decomposer can provide more balanced density which leads to less edge placement error (EPE), while the conflict and stitch numbers are still very comparable to our non-balanced-density baseline

    Monadic Decomposability of Regular Relations

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    Monadic decomposibility - the ability to determine whether a formula in a given logical theory can be decomposed into a boolean combination of monadic formulas - is a powerful tool for devising a decision procedure for a given logical theory. In this paper, we revisit a classical decision problem in automata theory: given a regular (a.k.a. synchronized rational) relation, determine whether it is recognizable, i.e., it has a monadic decomposition (that is, a representation as a boolean combination of cartesian products of regular languages). Regular relations are expressive formalisms which, using an appropriate string encoding, can capture relations definable in Presburger Arithmetic. In fact, their expressive power coincide with relations definable in a universal automatic structure; equivalently, those definable by finite set interpretations in WS1S (Weak Second Order Theory of One Successor). Determining whether a regular relation admits a recognizable relation was known to be decidable (and in exponential time for binary relations), but its precise complexity still hitherto remains open. Our main contribution is to fully settle the complexity of this decision problem by developing new techniques employing infinite Ramsey theory. The complexity for DFA (resp. NFA) representations of regular relations is shown to be NLOGSPACE-complete (resp. PSPACE-complete)

    Extramedullary versus intramedullary tibial alignment technique in total knee arthroplasty: A meta-analysis of randomized controlled trials

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    The aim of this study was to establish whether the use of an extramedullary or intramedullary tibial cutting guide leads to superior mechanical leg axis and implant positioning. A meta-analysis of six randomized controlled trials including 350 knees was performed. For the mechanical axis, frontal tibial component angle and tibial slope, there were no significant differences in the mean values or the number of outliers (±3°) between the extramedullary and intramedullary groups. A reduced tourniquet time was associated with the intramedullary guide. No significant difference in the complication rate was noted between the two groups. Neither extramedullary nor intramedullary tibial alignment was more accurate in facilitating the tibial cut. Use of an intramedullary guide results in a shorter tourniquet time and exhibits a similar complication rate as the extramedullary guide

    Application of the indirect fluorescent antibody assay in the study of malaria infection in the Yangtze River Three Gorges Reservoir, China

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    <p>Abstract</p> <p>Background</p> <p>China Yangtze Three Gorges Project (TGP) is one of the biggest construction projects in the world. The areas around the Three Gorge Dam has a history of tertian malaria and subtertian malaria epidemic, but there are no overall data about malaria epidemics before the completion of the project. The objective of this study was to get a reliable baseline on malaria infection in the Yangtze River Three Gorges reservoir area and to provide reference data for future studies about the impact of the project on malaria epidemics.</p> <p>Methods</p> <p>Two surveys of malaria infection were carried out in area, at six-month intervals in May and October 2008. About 3,600 dual specimens blood film samples for parasite diagnosis and filter paper blood spots for serology (using the immunofluorescence antibody test) were collected from the general population, including school populations, whenever possible.</p> <p>Results</p> <p>The overall percentage of positive response of the same population during post-transmission periods was about twice (1.40/0.72) of that in pre-transmission. Positive individuals under 15 years of age were detected in all the localities.</p> <p>Conclusion</p> <p>A certain extent of malaria infection existed in this area. Additional studies are needed to determine the length of malaria experience, and chemotherapeutic intervention as well as the distribution of main vectors for transmission in this area.</p

    9-{4-[(E)-2-(4,6-Dimethyl-1,3,5-triazin-2-yl)ethen­yl]phen­yl}-9H-carbazole

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    In the crystal structure of the title compound, C25H20N4, the triazinyl ring is nearly coplanar with the planar (r.m.s. deviation = 0.028 Å) phenyl­ethenyl unit, the twist being only 5.8 (2)°; however, the planar carbazolyl unit (r.m.s. deviation = 0.008 Å) is twisted by 47.8 (1)° with respect to the phenyl­ethenyl unit. The nonplanar nature of the mol­ecule explains the phenomenon of light emission at short wavelengths in the solid state but at long wavelengths in solution

    Global Structure Knowledge-Guided Relation Extraction Method for Visually-Rich Document

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    Visual relation extraction (VRE) aims to extract relations between entities from visuallyrich documents. Existing methods usually predict relations for each entity pair independently based on entity features but ignore the global structure information, i.e., dependencies between entity pairs. The absence of global structure information may make the model struggle to learn long-range relations and easily predict conflicted results. To alleviate such limitations, we propose a GlObal Structure knowledgeguided relation Extraction (GOSE) framework, which captures dependencies between entity pairs in an iterative manner. Given a scanned image of the document, GOSE firstly generates preliminary relation predictions on entity pairs. Secondly, it mines global structure knowledge based on prediction results of the previous iteration and further incorporates global structure knowledge into entity representations. This "generate-capture-incorporate" schema is performed multiple times so that entity representations and global structure knowledge can mutually reinforce each other. Extensive experiments show that GOSE not only outperforms previous methods on the standard fine-tuning setting but also shows promising superiority in cross-lingual learning; even yields stronger data-efficient performance in the low-resource setting.Comment: Work in progres
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