Simultaneous Optical Model Analyses of Elastic Scattering, Breakup, and Fusion Cross Section Data for the 6^{6}He + 209^{209}Bi System at Near-Coulomb-Barrier Energies

Based on an approach recently proposed by us, simultaneous $\chi^{2}$-analyses are performed for elastic scattering, direct reaction (DR) and fusion cross sections data for the $^{6}$He+$^{209}$Bi system at near-Coulomb-barrier energies to determine the parameters of the polarization potential consisting of DR and fusion parts. We show that the data are well reproduced by the resultant potential, which also satisfies the proper dispersion relation. A discussion is given of the nature of the threshold anomaly seen in the potential

Spin-one color superconductivity in compact stars?- an analysis within NJL-type models

We present results of a microscopic calculation using NJL-type model of possible spin-one pairings in two flavor quark matter for applications in compact star phenomenology. We focus on the color-spin locking phase (CSL) in which all quarks pair in a symmetric way, in which color and spin states are locked. The CSL condensate is particularly interesting for compact star applications since it is flavor symmetric and could easily satisfy charge neutrality. Moreover, the fact that in this phase all quarks are gapped might help to suppress the direct Urca process, consistent with cooling models. The order of magnitude of these small gaps (~1 MeV) will not influence the EoS, but their also small critical temperatures (T_c ~800 keV) could be relevant in the late stages neutron star evolution, when the temperature falls below this value and a CSL quark core could form.Comment: 7 pages, 7 figures, revised version, accepted for the Conference Proceedings of "Isolated Neutron Stars: from the Interior to the Surface", London, 24-28. April 200

Model Predictive Control for Distributed Microgrid Battery Energy Storage Systems

© 2017 IEEE. This brief proposes a new convex model predictive control (MPC) strategy for dynamic optimal power flow between battery energy storage (ES) systems distributed in an ac microgrid. The proposed control strategy uses a new problem formulation, based on a linear d-q reference frame voltage-current model and linearized power flow approximations. This allows the optimal power flows to be solved as a convex optimization problem, for which fast and robust solvers exist. The proposed method does not assume that real and reactive power flows are decoupled, allowing line losses, voltage constraints, and converter current constraints to be addressed. In addition, nonlinear variations in the charge and discharge efficiencies of lithium ion batteries are analyzed and included in the control strategy. Real-time digital simulations were carried out for an islanded microgrid based on the IEEE 13 bus prototypical feeder, with distributed battery ES systems and intermittent photovoltaic generation. It is shown that the proposed control strategy approaches the performance of a strategy based on nonconvex optimization, while reducing the required computation time by a factor of 1000, making it suitable for a real-time MPC implementation

Phenological characteristics of different winegrape cultivars in Central Italy

Statistical models based on temperature accumulation are used to estimate grapevine phenology (e.g. bud break, flowering) through summation of daily heat requirements calibrated from a base temperature and a given date. This study was designed to define the grapevine agro-phenological behaviour through analysis of potential trends of some principal phenological phenomena, such as flowering, harvest, and berry sugar levels at harvest. The data utilized were recorded over a 13-year period (2000-2012) for different grape varieties in the Umbria wine region in central Italy. Moreover, to determine the more important relationships between meteorological variables and recorded data, partial least-squares regressions were carried out. The trend analysis for berry sugar accumulation shows increasing degrees during the study period that were linked more to the 'Grechetto' cultivar than to the 'Chardonnay' and 'Merlot' cultivars, and then to 'Cabernet'. The statistical model that was focused on the study of the relationships between mean annual berry sugar levels and meteorological variables showed that mean maximum temperatures in April and July are the most important predictive variables for berry sugar accumulation, through their positive influence on berry sugar degree

Studying Configurations with QCA: Best Practices in Strategy and Organization Research

Qualitative Comparative Analysis (QCA) is increasingly applied in strategy and organization research. The main purpose of our essay is to support this growing community of QCA scholars by identifying best practices that can help guide researchers through the key stages of a QCA empirical study (model building, sampling, calibration, data analysis, reporting and interpretation of findings) and by providing examples of such practices drawn from strategy and organization studies. Coupled with this main purpose, we respond to Miller’s (2017) essay on configuration research by highlighting our points of agreement regarding his recommendations for configurational research and by addressing some of his concerns regarding QCA. Our article thus contributes to configurational research by articulating how to leverage QCA for enriching configurational theories of strategy and organization

Kink far below the Fermi level reveals new electron-magnon scattering channel in Fe

Many properties of real materials can be modeled using ab initio methods within a single-particle picture. However, for an accurate theoretical treatment of excited states, it is necessary to describe electron-electron correlations including interactions with bosons: phonons, plasmons, or magnons. In this work, by comparing spin- and momentum-resolved photoemission spectroscopy measurements to many-body calculations carried out with a newly developed first-principles method, we show that a kink in the electronic band dispersion of a ferromagnetic material can occur at much deeper binding energies than expected (E_b=1.5 eV). We demonstrate that the observed spectral signature reflects the formation of a many-body state that includes a photohole bound to a coherent superposition of renormalized spin-flip excitations. The existence of such a many-body state sheds new light on the physics of the electron-magnon interaction which is essential in fields such as spintronics and Fe-based superconductivity.Comment: 6 pages, 2 figure

What makes a mobile app successful in supporting health behaviour change?

YesIntroduction: Health promotion apps designed to support and reinforce health behaviours or to reduce risk behaviours are the most commonly downloaded apps. Such technologies have the potential to reach and deliver health care to new populations. But the extent to which they are successful in enabling the adoption of new and desired behaviours can vary. Some apps are more effective than others, some are free to download while others require a nominal or substantial charge. Cost alone is not indicative of quality or effectiveness. This is important because the use of health apps by the public will likely increase, as is the expectation that health care professionals understand this technology and its heuristic role in personalised health. Practitioners therefore need to be better informed regarding what makes a health app appealing to service users and successful as an intervention to facilitate behaviour change. Objective: This paper describes and discusses how the structure and content of health care apps can facilitate or inhibit behavioural change. The aim is to support practitioners in the screening and identification of suitable apps for clinical use. Method: Theory and literature review. Conclusion: App content that involved clinician input at the design stage and included internal drivers such as motivation, self-efficacy and illness understanding and external drivers such as illness information, social networking and user compatibility tend to do better in facilitating behaviour change than those that do not. Of these factors, motivation is considered to be the most important

Embracing Causal Complexity: The Emergence of a Neo-Configurational Perspective

Causal complexity has long been recognized as a ubiquitous feature underlying organizational phenomena, yet current theories and methodologies in management are for the most part not well suited to its direct study. The introduction of the Qualitative Comparative Analysis (QCA) configurational approach has led to a reinvigoration of configurational theory that embraces causal complexity explicitly. We argue that the burgeoning research using QCA represents more than a novel methodology; it constitutes the emergence of a neo-configurational perspective to the study of management and organizations that enables a fine-grained conceptualization and empirical investigation of causal complexity through the logic of set theory. In this article, we identify four foundational elements that characterize this emerging neoconfigurational perspective: 1) conceptualizing cases as set theoretic configurations; 2) calibrating cases’ memberships into sets; 3) viewing causality in terms of necessity and sufficiency relations between sets; and, 4) conducting counterfactual analysis of unobserved configurations. We then present a comprehensive review of the use of QCA in management studies that aims to capture the evolution of the neo-configurational perspective among management scholars. We close with a discussion of a research agenda that can further this neoconfigurational approach and thereby shift the attention of management research away from a focus on net effects and towards examining causal complexity