2,860 research outputs found

    Resonant quantum coherence of magnetization at excited states in nanospin systems with different crystal symmetries

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    The quantum interference effects induced by the Wess-Zumino term, or Berry phase are studied theoretically in resonant quantum coherence of magnetization vector between degenerate excited states in nanometer-scale single-domain ferromagnets in the absence of an external magnetic field. By applying the periodic instanton method in the spin-coherent-state path integral, we evaluate the low-lying tunnel splittings between degenerate excited states of neighboring wells. And the low-lying energy level spectrum of m-th excited states are obtained with the help of the Bloch theorem in one-dimensional periodic potential.Comment: 23 pages, final version and accepted by Eur. Phys. J.

    Non-equilibrium dynamics of simple spherical spin models

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    We investigate the non-equilibrium dynamics of spherical spin models with two-spin interactions. For the exactly solvable models of the d-dimensional spherical ferromagnet and the spherical Sherrington-Kirkpatrick model the asymptotic dynamics has for large times and for large waiting times the same formal structure. In the limit of large waiting times we find in both models an intermediate time scale, scaling as a power of the waiting time with an exponent smaller than one, and thus separating the time-translation invariant short-time dynamics from the aging regime. It is this time scale on which the fluctuation-dissipation regime is violated. Aging in these models is similar to that observed in spin glasses at the level of correlation functions, but different at the level of response functions, and thus different at the level of experimentally accessible quantities like the thermoremanent magnetization.Comment: 8 pages, 1 eps figur

    The Relationship between Secondary School Students’ Emotional Intelligence and Learning Motivation

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    In recent years, emotional intelligence has been highly regarded because of its ability to control emotions, develop talented potential, build high-quality relationships, and have leadership skills. Learning motivation is the motivation of achievement in learning, a psychological need for individuals to pursue success, and also one of the main factors affecting learning achievement. Both of them are very important to young adults. However, rare studies discuss the correlation between middle school students’ emotional intelligence and learning motivation. The purposes of this study were to explore the relationships between secondary school students’ emotional intelligence and learning motivation. Participants were 877 secondary school students selected from central Taiwan. A questionnaire was applied to collect data. Data were analyzed by using descriptive statistics, Pearson’s product-moment correlation, and multiple regression analysis. The findings of this study were as follows: First, the students’ perception of the current situations of emotional intelligence and learning motivation were above a moderate level. Second, there was a positive correlation between emotional intelligence and learning motivation. Third, emotional intelligence could predict learning motivation and the level of self-motivation was the best predictor. Conclusion and discussion were also included in this study. Keywords: Secondary school student, Emotional intelligence, Learning motivation DOI: 10.7176/JEP/12-5-02 Publication date: February 28th 202

    The Relationships among Senior High School Teacher Perceptions on Professional Learning Community, Self-efficacy, School Type, and Gender

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    Teacher’s professional learning community (TPLC) and self-efficacy(SE) are considered to enhance student learning in various dimensions. Teacher perceived PLC and SE might be influenced by school contexts and teachers’ demographic factors. This study investigated the relationships between teacher’s professional learning community (PLC), self-efficacy (SE), school type, and gender in Taiwan context. The findings are expected to provide valuable information in this field and to enhance understanding of PLC and self-efficacy in different cultural contexts. Descriptive statistics, t-test, product-moment correlation, and multiple regression analysis were applied to analyze the data. The findings indicated that a significant difference was found between public school teachers and private school teachers in two PLC dimensions, core element and human and social resources, and in one SE dimesnion, classroom management. Another significant differences were found between male teachers and female teachers in three SE dimensions, teaching strategy, classroom management, and student involvement. However, no significant differences was found between both in PLC dimesnions. Moreover, perceived PLC and SE were positive correlated. Perceived PLC could predict perceived SE. These results suggested that PLC appears to play a role in teachers’ reported levels of SE and provided initial evidence that the variation between schools in PLC may be explained by the SE. Keywords: Gender, school type, self-efficacy, professional learning community, senior high school teacher

    Practices of Market Making for Sustaining Electronic Auction

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    This article examines how technology may be used continuously in organizations. Particularly, it investigates the organizing practices that support continuous technology-use. Exploring such organizing practices is meaningful because they could sustain ongoing organizational innovation. A field study on the enterprise application of e-auction (electronic auction, or otherwise known as online reverse auction and electronic bidding) is used to illustrate how a marketplace is effectively maintained over a span of seven years. Our findings identify a set of market-making practices and its principles that underscore sustained use of e-auction. This research contributes to literature on technology-use and adoption, as well as adds to studies on the electronic marketplace. It also offers practical lessons to implementers who seek to adopt the e-auction to achieve significant cost-savings and streamline the supply chain

    A Submodular Optimization Framework for Outage-Aware Cell Association in Heterogeneous Cellular Networks

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    In cellular heterogeneous networks (HetNets), offloading users to small cell base stations (SBSs) leads to a degradation in signal to interference plus noise ratio (SINR) and results in high outage probabilities for offloaded users. In this paper, we propose a novel framework to solve the cell association problem with the intention of improving user outage performance while achieving load balancing across different tiers of BSs. We formulate a combinatorial utility maximization problem with weighted BS loads that achieves proportional fairness among users and also takes into account user outage performance. A formulation of the weighting parameters is proposed to discourage assigning users to BSs with high outage probabilities. In addition, we show that the combinatorial optimization problem can be reformulated as a monotone submodular maximization problem and it can be readily solved via a greedy algorithm with lazy evaluations. The obtained solution offers a constant performance guarantee to the cell association problem. Simulation results show that our proposed approach leads to over 30% reduction in outage probabilities for offloaded users and achieves load balancing across macrocell and small cell BSs
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