1,214 research outputs found

    Quantum Group Covariance and the Braided Structure of Deformed Oscillators

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    The connection between braided Hopf algebra structure and the quantum group covariance of deformed oscillators is constructed explicitly. In this context we provide deformations of the Hopf algebra of functions on SU(1,1). Quantum subgroups and their representations are also discussed.Comment: 12 pages, to be published in JM

    Braided Oscillators

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    The braided Hopf algebra structure of the generalized oscillator is investigated. Using the solutions two types of braided Fibonacci oscillators are introduced. This leads to two types of braided Biedenharn-Macfarlane oscillators.Comment: 12 pages, latex, some references added, published versio

    Symmetric Skyrmions

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    We present candidates for the global minimum energy solitons of charge one to nine in the Skyrme model, generated using sophisticated numerical algorithms. Assuming the Skyrme model accurately represents the low energy limit of QCD, these configurations correspond to the classical nuclear ground states of the light elements. The solitons found are particularly symmetric, for example, the charge seven skyrmion has icosahedral symmetry, and the shapes are shown to fit a remarkable sequence defined by a geometric energy minimization (GEM) rule. We also calculate the energies and sizes to within at least a few percent accuracy. These calculations provide the basis for a future investigation of the low energy vibrational modes of skyrmions and hence the possibility of testing the Skyrme model against experiment.Comment: latex, 9 pages, 1 figure (fig1.gif

    The role of the supply chain in the elimination and reduction of construction rework and defects: an action research approach

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    Since 2007, Ireland has suffered a circa 80% reduction in construction output. This has resulted in bankruptcy, unemployment and bad debt. Contractors have attached greater emphasis to production efficiency and cost reduction as a means of survival. An Action Research (AR) strategy was used in this research to improve processes adopted by a SME contractor for the control of defects in its supply chain. It is conservatively estimated that rework, typically accounts for, circa 5% of total project costs. Rework is wasteful and presents an obvious target for improvement. The research reported here concerns the (first) diagnosing stage of the AR cycle only, involving: observation of fieldwork, analysis of contract documents, and semi-structured interviews with supply chain members. The results indicate potential for supply chain participants to identify root causes of defects and propose solutions, having regard to best practice to avoid re-occurrence. A lack of collaborative forums to contribute to production improvement was identified. Additionally the processes, used to collect, manage and disseminate data were unstructured and uncoordinated, indicating scope for developing more efficient methods. The research indicates good understanding of the potential benefits for supply chain collaboration but suggests that the tools and knowledge to collaborate are currently lacking in the SME sector

    Elementary Science Teachers Perceived Self-Efficacy: A Correlational Study between Teachers with Content and Non-Content Major Degrees in New Jersey

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    This predictive, correlational study examines the relationship between undergraduate degree type, methods courses taken in undergraduate school, and the number of years teaching the same grade level and elementary science teachers’ perceived self-efficacy. In this non-experimental study, participants submitted their online responses to the 25-item survey, Science Teaching Efficacy Belief Instrument (STEBI-A), and their demographic information via Google Forms. The researcher used multiple regression to analyze participants’ anonymous responses. In using a multiple linear regression analysis, the researcher examined the results of the STEBI-A to determine how accurately an elementary science teachers’ perceived self-efficacy is predicted by the predictor variable of type of undergraduate degree earned, years of teaching the same grade for elementary science teachers. The type of degree and science method courses variables did not display an ability to predict elementary science teacher self-efficacy. The participants for the study came from a snowball sample of elementary school teachers located in New Jersey during the summer semester of the 2022-2023 school year with N = 138 with a minimum of N = 71. The study revealed a statistically significant relationship between self-efficacy and the number of years of teaching the same grade level; however, undergraduate degree earned, and science methods courses did not show a statistically significant contribution to the overall model. Based on the results of this study a multiple regression study with degree type and subject matter professional development exposure as predictive variables is recommended

    Zero mode quantization of multi-Skyrmions

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    A zero mode quantization of the minimal energy SU(2) Skyrmions for nucleon numbers four to nine and seventeen is described. This involves quantizing the rotational and isorotational modes of the configurations. For nucleon numbers four, six and eight the ground states obtained are in agreement with the observed nuclear states of Helium, Lithium and Beryllium. However, for nucleon numbers five, seven, nine and seventeen the spins obtained conflict with the observed isodoublet nuclear states.Comment: 37 pages, LaTeX, 4 figures. More careful treatment of double covers, reference adde

    Can forest management based on natural disturbances maintain ecological resilience?

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    Given the increasingly global stresses on forests, many ecologists argue that managers must maintain ecological resilience: the capacity of ecosystems to absorb disturbances without undergoing fundamental change. In this review we ask: Can the emerging paradigm of natural-disturbance-based management (NDBM) maintain ecological resilience in managed forests? Applying resilience theory requires careful articulation of the ecosystem state under consideration, the disturbances and stresses that affect the persistence of possible alternative states, and the spatial and temporal scales of management relevance. Implementing NDBM while maintaining resilience means recognizing that (i) biodiversity is important for long-term ecosystem persistence, (ii) natural disturbances play a critical role as a generator of structural and compositional heterogeneity at multiple scales, and (iii) traditional management tends to produce forests more homogeneous than those disturbed naturally and increases the likelihood of unexpected catastrophic change by constraining variation of key environmental processes. NDBM may maintain resilience if silvicultural strategies retain the structures and processes that perpetuate desired states while reducing those that enhance resilience of undesirable states. Such strategies require an understanding of harvesting impacts on slow ecosystem processes, such as seed-bank or nutrient dynamics, which in the long term can lead to ecological surprises by altering the forest's capacity to reorganize after disturbance

    A design theory for e-service environments: The interoperability challenge

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    The delivery of e-services across organizational boundaries poses a number of issues in terms of design of inter-organizational systems that support service delivery effectively. In this context interoperability emerges as a mandatory requirement for the design of Information Technology (IT) platforms supporting collaborative e-service environments. In this paper we address this issue by presenting a design theory for IT platforms supporting e-services based on both a deep understanding of the interoperability concept and a design research approach. Through the analysis of a cooperation framework developed in the context of an EU funded project, we instantiate the theory by providing the concrete example of a solution addressing this design problem. © 2012 Springer-Verlag GmbH Berlin Heidelberg.The delivery of e-services across organizational boundaries poses a number of issues in terms of design of inter-organizational systems that support service delivery effectively. In this context interoperability emerges as a mandatory requirement for the design of Information Technology (IT) platforms supporting collaborative e-service environments. In this paper we address this issue by presenting a design theory for IT platforms supporting e-services based on both a deep understanding of the interoperability concept and a design research approach. Through the analysis of a cooperation framework developed in the context of an EU funded project, we instantiate the theory by providing the concrete example of a solution addressing this design problem. © 2012 Springer-Verlag GmbH Berlin Heidelberg.Monograph's chapter

    Enterprise Resource Planning and Organizational Knowledge: Patterns of Convergence and Divergence

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    This paper reports on a qualitative research study to investigate how enterprise resource planning systems impact organizational knowledge. Cognitive mapping methodology was used to capture and analyze the perspectives of senior managers from the IT and user organizations of a major corporation. The results indicate that ERP systems produce effects that make business knowledge become more focused or convergent from the perspective of the organization and more wide-ranging or divergent from the perspective of the individual. Other important effects include changes to the organization\u27s core competencies and changes in the risk profile regarding the loss of organizational knowledge. The research contributes to the knowledge-based view of enterprise systems
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