5,479 research outputs found

    Unique and interactive effects of moral emotions and moral disengagement on bullying and defending among school children

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    The first aim of the present study was to examine in a single model how moral disengagement and moral emotions were related to bullying and defending behavior among schoolchildren. The second aim was to test whether the two moral dimensions interacted with each other to explain behavior in bullying situations. Data were collected from 561 Swedish students. Moral disengagement was positively associated with bullying and negatively associated with defending, whereas moral emotions score was negatively associated with bullying and positively associated with defending. Moreover, students who scored high in moral emotions did not tend to bully other students, irrespective of their levels of moral disengagement, whereas when the moral emotions score was low bullying behavior increased with increasing levels of moral disengagement. In contrast, moral disengagement was negatively related to defending behavior at low levels of moral emotions, but not when moral emotions were high

    Short Cycle Covers of Cubic Graphs and Graphs with Minimum Degree Three

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    The Shortest Cycle Cover Conjecture of Alon and Tarsi asserts that the edges of every bridgeless graph with mm edges can be covered by cycles of total length at most 7m/5=1.400m7m/5=1.400m. We show that every cubic bridgeless graph has a cycle cover of total length at most 34m/211.619m34m/21\approx 1.619m and every bridgeless graph with minimum degree three has a cycle cover of total length at most 44m/271.630m44m/27\approx 1.630m

    Structures and transitions in bcc tungsten grain boundaries and their role in the absorption of point defects

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    We use atomistic simulations to investigate grain boundary (GB) phase transitions in el- emental body-centered cubic (bcc) metal tungsten. Motivated by recent modeling study of grain boundary phase transitions in [100] symmetric tilt boundaries in face-centered cu- bic (fcc) copper, we perform a systematic investigation of [100] and [110] symmetric tilt high-angle and low-angle boundaries in bcc tungsten. The structures of these boundaries have been investigated previously by atomistic simulations in several different bcc metals including tungsten using the the {\gamma}-surface method, which has limitations. In this work we use a recently developed computational tool based on the USPEX structure prediction code to perform an evolutionary grand canonical search of GB structure at 0 K. For high-angle [100] tilt boundaries the ground states generated by the evolutionary algorithm agree with the predictions of the {\gamma}-surface method. For the [110] tilt boundaries, the search predicts novel high-density low-energy grain boundary structures and multiple grain boundary phases within the entire misorientation range. Molecular dynamics simulation demonstrate that the new structures are more stable at high temperature. We observe first-order grain boundary phase transitions and investigate how the structural multiplicity affects the mechanisms of the point defect absorption. Specifically, we demonstrate a two-step nucleation process, when initially the point defects are absorbed through a formation of a metastable GB structure with higher density, followed by a transformation of this structure into a GB interstitial loop or a different GB phase.Comment: 40 pages, 19 figure

    Structural Change in Transition: A Role for Organizational Legitimacy? Evidence from Czech Agriculture

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    Market liberalization in Central and Eastern Europe was targeted at establishing incentives that would improve economic performance. While substantial reorganization of enterprises is observed, firms can also be observed which devote resources towards establishing organizational legitimacy. Motivations for such behavior are considered and empirical evidence of its relationship with technical efficiency using a distance function approach is analyzed for the case of Czech agriculture. Contrary to the expectation that such behavior would be inefficient, we find that firms reap private economic gains from legitimacy efforts through improved access to agricultural land, investment subsidies and firm internal social capital. However, its effect on technical efficiency depends on whether such legitimacy efforts are valued by stakeholders or understood as a norm. Evidence of the trade-off between gains or sustainability from legitimacy and reorganization thus brings a new perspective to the understanding of structural changes in transition.organizational legitimacy, efficiency, structural change, transition, agriculture, Industrial Organization, D21, D23, D24,

    Quality of geographic information - simple concept made complex by the context

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    Geographic information is increasingly being shared by many users across different fields and applications. Due to the new, widely available and easy-to-use data collection instruments and information publishing facilities the reliability of data, which is tightly coupled with its quality becomes of paramount interest. The notion of data quality is being transformed ¿ in addition to addressing the a priori requirements for data production the need for reporting the fitness for use has opened a new approach. The latter is especially pertinent in the context of Spatial Data and Information Infrastructures (SDIs). Even though the term data quality seems to be trivial, its discussion is rather difficult because of the assumptions, incoherent use of terminology and the diverging points of view. The paper will enlighten aspects of data quality from point of view of users and data producers both in the context of data production and SDIs emphasising similarities and differences. A possible way of dealing with data quality in SDIs will be described using the example of INSPIREJRC.H.6-Spatial data infrastructure

    ON THE NEED FOR TOOLS TO SUPPORT SEARCH IN SOFTWARE REUSE: A Perspective Paper Presented to Seer Technologies, Inc.

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    Software reuse in the presence of a repository and object-based CASE tool is likely to be "biased." Prior research (Banker, Kauffman and Zweig, 1991) showed that a developer will be: most likely to reuse her own objects; somewhat less likely to reuse objects developed by her project team members; and, even less likely to reuse objects stored in the repository, but developed elsewhere in the corporation. This paper characterizes this problem in terms of three familiarity biases: personal bias, project bias and time bias. In the presence of these biases it is appropriate to deploy tools that support the search for software reuse, so that they may be overcome. However, the tools that are chosen or created for this purpose must adequately treat the technical and cognitive fundamentals for individual developers, and recognize the organizational and economic perspectives of a firm that wishes to maximize the business value of its software development activities.Information Systems Working Papers Serie

    SUPPORTING SEARCH FOR REUSABLE SOFTWARE OBJECTS

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    Software reuse in the presence of a repository and object-based CASE tool is likely to be "biased" Prior research has shown that a developer will be: (1) most likely to reuse her own objects; (2) somewhat less likely to reuse objects developed by her project team members; and, (3) even less likely to reuse objects stored in the repository, but developed elsewhere in the corporation. These biases can result in sub-optimal levels of software reuse. In the presence of such biases it is appropriate to deploy tools that support the search for software reuse, so that developers find it easier to reuse software objects authored by developers other than themselves or project team members. However; the tools that are chosen or created for this purpose must adequately treat the technical and cognitive fundamentals of the problem for individual developers, and recognize the organizational and economic perspectives of a firm that wishes to maximize the business value of its software development activities. In this paper we present a two-stage descriptive model that represents the search process for reusable software objects. We evaluate appropriate technologies, propose a technical solution to the problem of searching for reusable objects, and demonstrate its feasibility via a prototype implementation. The technical tool combines an automated classifier and a hypertext system. We describe an architecture to automatically create hypertext networks based on the classification schema. We illustrate our architecture using a classification of software objects obtained through structured interviews with software developers.Information Systems Working Papers Serie

    Regression-based seasonal unit root tests

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    The contribution of this paper is three-fold. Firstly, a characterisation theorem of the sub-hypotheses comprising the seasonal unit root hypothesis is presented which provides a precise formulation of the alternative hypotheses against which regression-based seasonal unit root tests test. Secondly, it proposes regressionbased tests for the seasonal unit root hypothesis which allow a general seasonal aspect for the data and are similar both exactly and asymptotically with respect to initial values and seasonal drift parameters. Thirdly, limiting distribution theory is given for these statistics where, in contrast to previous papers in the literature, in doing so it is not assumed that unit roots hold at all of the zero and seasonal frequencies. This is shown to alter the large sample null distribution theory for regression t-statistics for unit roots at the complex frequencies, but interestingly to not affect the limiting null distributions of the regression t-statistics for unit roots at the zero and Nyquist frequencies and regression Fstatistics for unit roots at the complex frequencies. Our results therefore have important implications for how tests of the seasonal unit root hypothesis should be conducted in practice. Associated simulation evidence on the size and power properties of the statistics presented in this paper is given which is consonant with the predictions from the large sample theory.Seasonal unit root tests; seasonal drifts; characterisation theorem

    Confocal Ellipsoidal Reflector System for a Mechanically Scanned Active Terahertz Imager

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    We present the design of a reflector system that can rapidly scan and refocus a terahertz beam for high-resolution standoff imaging applications. The proposed optical system utilizes a confocal Gregorian geometry with a small mechanical rotating mirror and an axial displacement of the feed. For operation at submillimeter wavelengths and standoff ranges of many meters, the imaging targets are electrically very close to the antenna aperture. Therefore the main reflector surface must be an ellipse, instead of a parabola, in order to achieve the best imaging performance. Here we demonstrate how a simple design equivalence can be used to generalize the design of a Gregorian reflector system based on a paraboloidal main reflector to one with an ellipsoidal main reflector. The system parameters are determined by minimizing the optical path length error, and the results are validated with numerical simulations from the commercial antenna software package GRASP. The system is able to scan the beam over 0.5 m in cross-range at a 25 m standoff range with less than 1% increase of the half-power beam-width
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