339 research outputs found

    Vertices with the Second Neighborhood Property in Eulerian Digraphs

    Full text link
    The Second Neighborhood Conjecture states that every simple digraph has a vertex whose second out-neighborhood is at least as large as its first out-neighborhood, i.e. a vertex with the Second Neighborhood Property. A cycle intersection graph of an even graph is a new graph whose vertices are the cycles in a cycle decomposition of the original graph and whose edges represent vertex intersections of the cycles. By using a digraph variant of this concept, we prove that Eulerian digraphs which admit a simple dicycle intersection graph have not only adhere to the Second Neighborhood Conjecture, but have a vertex of minimum outdegree that has the Second Neighborhood Property.Comment: fixed an error in an earlier version and made structural change

    Defining urban graphic heritage for economic development in the UK and China

    Get PDF
    What new perspectives can graphic design contribute to design for heritage? This paper provides answers to this question by confirming the meaning of heritage and the value of research in the context of a vibrant and evolving creative industries in the United Kingdom and China. Heritage has become an important topic for research in recent decades, and now features as a priority area with research councils. Increasingly, it is framed as cultural heritage, but the meaning of culture is unclear. In outlining the challenges associated with rapid urban development in China, and the importance of design, planning and heritage, a framework for analysing urban graphic heritage is proffered alongside empirical research from the United Kingdom and China. Despite its importance being overlooked in heritage discourse as well as contemporary reviews of the creative industries, graphic design is shown to provide a unique overarching perspective for the design challenges associated with the human experience of urban heritage

    Scenario-based design and evaluation for capability

    Get PDF
    Scenarios are frequently used within techniques for planning and designing systems. They are an especially helpful means of visualizing and understanding the incorporation of new systems within systems of systems. If used as the basis for decisions about candidate designs, then it is important that such decisions can be rationalized and quantitative assessment is particularly important. In this paper, an approach for developing complex scenarios, which incorporates the phases of systems development and deployment, is presented and a quantitative method of comparison is described. This approach is based on the development of measures of merit and measures of performance. The techniques are illustrated using cases that are relevant to Network Enabled Capability

    A demonstration of a service oriented virtual environment for complex system analysis

    Get PDF
    Distributed virtual simulation is increasingly in demand within the automotive industry. A distributed and networked approach to system level design and simulation stands to benefit from a unifying relational oriented modeling and simulation framework. This will permit innovative use of existing independent simulations for increased concurrency in design and verification and validation. This paper demonstrates an analysis of the vehicle as a complex system through the combination of a relational framework, high level syntax and semantics for representing models and distributed simulation. This promises to provide a rigorous, traceable and agile approach to conceptual vehicle design and analysis

    Scenario-based design and evaluation for capability

    Get PDF
    Scenarios are frequently used within techniques for planning and designing systems. They are an especially helpful means of visualizing and understanding the incorporation of new systems within systems of systems. If used as the basis for decisions about candidate designs, then it is important that such decisions can be rationalized and quantitative assessment is particularly important. In this paper, an approach for developing complex scenarios, which incorporates the phases of systems development and deployment, is presented and a quantitative method of comparison is described. This approach is based on the development of measures of merit and measures of performance. The techniques are illustrated using cases that are relevant to Network Enabled Capability

    In Situ Generation of Formaldehyde and Triphenylphosphine from (Hydroxymethyl)triphenylphosphonium and Its Application in Wittig Olefination

    No full text
    <div><p></p><p>The reaction of (hydroxymethyl)triphenylphosphonium with benzylic or allylic halide under basic conditions at room temperature affords terminal alkenes in 61–89% yields. In this reaction, both formaldehyde and triphenylphosphine are in situ generated from (hydroxymethyl)triphenylphosphonium and further undergo Wittig olefination with benzylic or allylic halide.</p></div

    Conformational transition of Aβ42 peptides in SM system, cholesterol & SM system and membrane system.

    No full text
    <p>SM slightly increased the β-sheet structure, but the mixture of SM and cholesterol had a strong enhancing effect, which was similar to free cholesterol system. Meanwhile, the DPPC bilayer seemed to moderately increased β-sheet structure.</p

    Interaction between cholesterol and mutant Ser19.

    No full text
    <p>The hydrogen atoms in amine group and alcohol group of serine formed hydrogen bonds with oxygen atoms in hydroxyl group of cholesterol. This made the peptide backbone prone to be perpendicular to the hydrophobic surface formed by cholesterol molecules. The ribbon of Aβ42 peptide is displayed in orange.</p

    The conformational transition of peptides in simple system (a), free cholesterol system (b), cholesterol & mutant system (c) and context mutation system (d).

    No full text
    <p>The plots show the secondary structures of four peptides (axis y) in each system as a function of time (axis x). Secondary structures are drawn in different colors, with β-sheet structure in red.</p
    corecore