546 research outputs found

    A Dynamical Study of the Non-Star Forming Translucent Molecular Cloud MBM16: Evidence for Shear Driven Turbulence in the Interstellar Medium

    Get PDF
    We present the results of a velocity correlation study of the high latitude cloud MBM16 using a fully sampled 12^{12}CO map, supplemented by new 13^{13}CO data. We find a correlation length of 0.4 pc. This is similar in size to the formaldehyde clumps described in our previous study. We associate this correlated motion with coherent structures within the turbulent flow. Such structures are generated by free shear flows. Their presence in this non-star forming cloud indicates that kinetic energy is being supplied to the internal turbulence by an external shear flow. Such large scale driving over long times is a possible solution to the dissipation problem for molecular cloud turbulence.Comment: Uses AAS aasms4.sty macros. Accepted for publication in Ap

    Usage Frequency of Product Configuration Systems Relative to Integrations and Fields of Application

    Get PDF
    Product Configuration Systems (PCS) are automatic solutions that can support and facilitate the sales and engineering processes. PCSs have recently attracted increased attention both from the researchers and practitioners. There are a variety of challenges reported in the literature as consequences of using PCS, which reduces the usage frequency of the system. To address those challenges, IT integrations can be an effective solution to reduce the number of manual tasks and complexity inside PCSs and make PCSs more user-friendly. However, the influence of integrating PCS to different IT systems on usage frequency has not been addressed in the literature. This paper aims to study the relationship of PCS usage frequency in terms of (1) different application area of the PCSs, and (2) integrations to different IT systems. The research method adopted in the paper is survey-based conducted in one company where the unit of analysis is operating PCS

    Differences in faces do make a difference: Diversity perceptions and preferences in faces

    Get PDF
    Throughout previous research focusing on individuals' diversity perception, it remains somewhat unclear which attributes (i.e., objective diversity) are reflected in perceptions of diversity. This manuscript investigates whether individuals consider objective differences in ambiguous facial information (which are not related to gender or race) when making diversity judgments and decisions. Throughout seven studies, facial information of group members was manipulated to appear more similar or different in regards to personality and information unrelated to Big 5 dimensions, while race, gender, and age were kept constant. Study 1a provides support that objective differences in facial information related to perceived personality traits is validly reflected in perceptions of diversity. Study 1b shows that results regarding the Big 5 can be replicated in an ensemble-coding setup. Studies 2a and 2b replicate this result, additionally showing that objective differences in facial information unrelated to the Big 5 are reflected in perceptions of diversity, too. Focusing on perceived extraversion, Study 3 reveals that individuals select faces differing (similar) in extraversion information in order to assemble a diverse (homogeneous) team. Study 4 investigates diversity choices in an ambiguous setting, showing that individuals who more strongly believe in the value of diversity are more likely to assemble a team that is objectively diverse regarding facial information. Study 5 indicates that the association between diversity in facial information and choices deteriorates if other attributes such as gender are varied too. The impact of the results for research is highlighted and discussed

    Additional symmetries of constrained CKP and BKP hierarchies

    Full text link
    The additional symmetries of the constrained CKP (cCKP) and BKP (cBKP) hierarchies are given by their actions on the Lax operators, and their actions on the eigenfunction and adjoint eigenfunction {Φi,Ψi}\{\Phi_i,\Psi_i \} are presented explicitly. Furthermore, we show that acting on the space of the wave operator, k\partial_k^* forms new centerless W1+cCW^{cC}_{1+\infty} and W1+cBW^{cB}_{1+\infty}-subalgebra of centerless W1+W_{1+\infty} respectively. In order to define above symmetry flows k\partial_k^* of the cCKP and cBKP hierarchies, two vital operators YkY_k are introduced to revise the additional symmetry flows of the CKP and BKP hierarchies.Comment: 14 pages, accepted by SCIENCE CHINA Mathematics(2010

    Iterative algorithms for total variation-like reconstructions in seismic tomography

    Full text link
    A qualitative comparison of total variation like penalties (total variation, Huber variant of total variation, total generalized variation, ...) is made in the context of global seismic tomography. Both penalized and constrained formulations of seismic recovery problems are treated. A number of simple iterative recovery algorithms applicable to these problems are described. The convergence speed of these algorithms is compared numerically in this setting. For the constrained formulation a new algorithm is proposed and its convergence is proven.Comment: 28 pages, 8 figures. Corrected sign errors in formula (25

    I love you too much to keep social distance: Closeness in relationships and (dis)engagement in preventive behaviors during the COVID-19 pandemic

    Get PDF
    : Although we are witnessing a new phase in the management of COVID-19, understanding what predicts adherence to preventive behaviors still remains crucial. In this study we focus on interpersonal relationships by specifically investigating whether engagement in preventive behaviors when in the presence of others may be a function of the type of relationship (in terms of closeness) one has with others. Because close others are often perceived similar to the self compared to strangers, we put forward that close relationships may inadvertently decrease COVID-19 risk perceptions which may ultimately decrease compliance with recommended behaviors when in their presence. To test this hypothesis, 747 Italian respondents were invited to answer one out of four versions of a questionnaire differing on the target (i.e., friends vs. parents vs. grandparents vs. strangers), including questions regarding COVID-19 risk perceptions and intentions to engage in preventive behaviors. Mediation analysis showed that close relationships (i.e., with friends, parents, and grandparents) compared to nonclose relationships (i.e., with strangers) predicted lower intentions to engage in preventive behaviors via lower risk perceptions. Altogether, these results shed light on the role played by closeness in indirectly shaping individuals' dis(engagement) in preventive behaviors and contribute to better understand possible unconscious biases which may undermine our safety during the COVID-19 pandemic

    On the performance of algorithms for the minimization of 1\ell_1-penalized functionals

    Full text link
    The problem of assessing the performance of algorithms used for the minimization of an 1\ell_1-penalized least-squares functional, for a range of penalty parameters, is investigated. A criterion that uses the idea of `approximation isochrones' is introduced. Five different iterative minimization algorithms are tested and compared, as well as two warm-start strategies. Both well-conditioned and ill-conditioned problems are used in the comparison, and the contrast between these two categories is highlighted.Comment: 18 pages, 10 figures; v3: expanded version with an additional synthetic test problem

    At the core of cyberaggression: A group-based explanation

    Get PDF
    In this study, prototypicality of the aggressor was tested as a group-level factor predicting social media users' active participation in cyberaggression. Participants were exposed to a fictitious conversation, in which either a prototypical versus non-prototypical user posted an aggressive comment as a reply to a provocative comment. In line with self-categorization theory, we hypothesized that bystander participants would post an aggressive comment and rate the aggression as acceptable to a greater extent in the prototypical than in the non-prototypical condition. Furthermore, we predicted that perceived normativity of aggression would mediate the effect of prototypicality. Results supported these predictions and showed that prototypical members affect the extent to which collective aggressive behaviors in online interactions are approved and enacted. These findings highlight the importance of group-level factors in the study of cyberaggression and provide important information for understanding the psychological underpinnings of collective forms of online aggression

    Polynomials Associated with Equilibria of Affine Toda-Sutherland Systems

    Full text link
    An affine Toda-Sutherland system is a quasi-exactly solvable multi-particle dynamics based on an affine simple root system. It is a `cross' between two well-known integrable multi-particle dynamics, an affine Toda molecule and a Sutherland system. Polynomials describing the equilibrium positions of affine Toda-Sutherland systems are determined for all affine simple root systems.Comment: 9 page
    corecore