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Abstract: A tree which has exactly one vertex of degree greater than two is said to be starlike. In spite of seemingly simple structure of these trees, not much is known about their spectral properties. In this paper, we introduce a generalization of the notion of cospectrality called -cospectrality which turns out to be useful in constructing cospectral graphs. Based on this, we construct cospectral mates for some starlike trees. We also present a set of necessary and sufficient conditions for divisibility of the characteristic polynomial of a starlike tree by the characteristic polynomial of a path. [Copyright &y& Elsevier]

Abstract: Measurement of short-term and long-term deflections is a necessary step towards understanding and evaluating the status of a bridge. In this paper, a novel non-contact weighted-stretched-wire (NCWSW) system is developed for measuring the deflection of a bridge. Also some factors related to the system are addressed. The proposed system is promising due to some attractive features such as high precision, low implementation cost and suitability for continuous monitoring. The efficiency and reliability of NCWSW system are investigated both analytically and experimentally. A realistic NCWSW system has been used in the monitoring of a real-world bridge. [Copyright &y& Elsevier]

Abstract: In this paper we expose new method to analyse time series. The method is essentially applied for the prediction of time series among approximation and modelisation. It is based on wavelet decomposition combined with autoregressive models. An iterative procedure is applied and the performance of the estimator is measured by standardized error. Finally, a comparison with some existing models and methods has been pointed out to prove the performance of our’s. [Copyright &y& Elsevier]

Abstract: The sheet carrier concentrations, conduction band profiles and amount of free carriers in the barriers have been determined by solving coupled Schrödinger and Poisson equation self-consistently for coherently grown Al0.3Ga0.7N/GaN and Al0.3Ga0.7N/AlN/GaN structures on thick GaN. The Al0.3Ga0.7N/GaN heterojunction structures with and without 1nm AlN interlayer have been grown by MOCVD on sapphire substrate, the physical properties for these two structures have been investigated by various instruments such as Hall measurement and X-ray diffraction. By comparison of the theoretical and experimental results, we demonstrate that the sheet carrier concentration and the electrons mobility would be improved by the introduction of an AlN interlayer for Al0.3Ga0.7N/GaN structure. Mechanisms for the increasing of the sheet carrier concentration and the electrons mobility will be discussed in this paper. [Copyright &y& Elsevier]

Abstract: An RNA secondary structure is considered to be planar if its arc graph can be embedded into a plane without edge crossing. In this paper, a graphical criterion of planarity is presented based on graphical composition for RNA secondary structures with pseudoknots in Rivas–Eddy Class. Effective planar testing algorithms are introduced based on our graphical criterion. [Copyright &y& Elsevier]

Abstract: The objective of this paper is to describe a simple dynamic crack propagation experiment which reproduces two phenomena: mixed-mode propagation and crack stop and restart. This experiment is explained and interpreted using X-FEM simulations. We show that a simple fracture theory which consists in using a dynamic crack initiation toughness, a crack orientation along the maximum principal stress and a simple equation for the calculation of the crack speed is sufficient to explain what is observed experimentally. [Copyright &y& Elsevier]

Abstract: Previous studies of aspiration and VOT in Japanese have led to /p/, /t/, and /k/ being inconsistently described as either unaspirated or moderately aspirated. The purpose of this paper is to resolve this issue. Assessing the productions of 13 monolingual Japanese talkers living in Japan, we repeated part of a VOT study that was based on 6 Japanese bilinguals living in the UK. For each talker we assessed the VOT in 44 voiceless stops, including 12 for /p/, 12 for /t/, and 20 for /k/. We found that Japanese VOT for /p/, /t/, and /k/ was 30.0, 28.5, and 56.7ms, respectively, and longer than the VOT of two short lag comparison groups and shorter than the VOT of two long lag comparison groups. We conclude that Japanese voiceless stops have an intermediate degree of aspiration and constitute an exception to the short lag and long lag dichotomy of voiceless stops said to characterize many languages. [Copyright &y& Elsevier]

Abstract: The purpose of this paper is to show that various classes of operators having a common collection of root spaces whose closed linear span equals the entire space have dense sets of common cyclic vectors. [Copyright &y& Elsevier]

Abstract: This paper deals with a parabolic system, cross-coupled via a nonlinear source and a nonlinear boundary flux. We get a necessary and sufficient condition for the existence of non-simultaneous blow-up. In particular, four different simultaneous blow-up rates are obtained in different regions of parameters, described by an introduced characteristic algebraic system. It is observed that different initial data may result in different simultaneous blow-up rates even in the same region of parameters. [Copyright &y& Elsevier]

Abstract: Small pieces of metal are generated during trimming of automotive body panels. Commonly referred to as slivers, these pieces can be imprinted into the surface of stamped panels. This may require metalfinish of every stamped exterior panel. The objective of the paper is to study the influence of trimming conditions on quality of trimmed surface and to modify the trimming process to eliminate slivers and burrs from trimmed surface. This objective is being accomplished through numerical simulation of the blank fracture and experimental study of trimmed surface formation. Suggested solution includes two measures: (1) building an elastic support of the offal eliminating bending of the part of the blank being trimmed off; (2) creating the preference of crack propagation from the lower shearing edge by machining a small radius on the upper shearing edge. [Copyright &y& Elsevier]

Abstract: In this paper we deal with the construction of global fuzzy preference structures from two-parameter single-criterion fuzzy outranking relations proposed in [10] and which are based on the aggregation of outranking indices associated with -cuts. We consider two ways of constructing global fuzzy preference structures: (i) aggregate the two-parameter single-criterion fuzzy outranking relations and then construct the global fuzzy preference structures and (ii) construct global fuzzy preference structures and then aggregate the single-criterion fuzzy preference, indifference and incomparability relations. We also investigate the case where these two ways of proceeding lead to the same results. [Copyright &y& Elsevier]

Abstract: Given a set D of positive integers, the distance graph has vertices all integers Z, and two vertices j and in Z are adjacent if and only if . This paper determines the circular chromatic numbers of some distance graphs. [Copyright &y& Elsevier]

This article deals with the continued consumption of paper. It was assumed that computer technology has the potential of reducing the use of paper. However, every country in the Western world uses more paper as of December 2005, on a per-capita basis, that it did ten years ago. Cognitive psychologists and ergonomics experts argued that paper persisted for very good reasons: when it comes to performing certain kinds of cognitive tasks, paper has many advantages over computers. The fundamental confusion about the role of paper makes people feel dismayed at the sight of a disorganized desk.