1,977 research outputs found

    Coordination approaches and systems - part I : a strategic perspective

    Get PDF
    This is the first part of a two-part paper presenting a fundamental review and summary of research of design coordination and cooperation technologies. The theme of this review is aimed at the research conducted within the decision management aspect of design coordination. The focus is therefore on the strategies involved in making decisions and how these strategies are used to satisfy design requirements. The paper reviews research within collaborative and coordinated design, project and workflow management, and, task and organization models. The research reviewed has attempted to identify fundamental coordination mechanisms from different domains, however it is concluded that domain independent mechanisms need to be augmented with domain specific mechanisms to facilitate coordination. Part II is a review of design coordination from an operational perspective

    Likelihood Analysis of Power Spectra and Generalized Moment Problems

    Full text link
    We develop an approach to spectral estimation that has been advocated by Ferrante, Masiero and Pavon and, in the context of the scalar-valued covariance extension problem, by Enqvist and Karlsson. The aim is to determine the power spectrum that is consistent with given moments and minimizes the relative entropy between the probability law of the underlying Gaussian stochastic process to that of a prior. The approach is analogous to the framework of earlier work by Byrnes, Georgiou and Lindquist and can also be viewed as a generalization of the classical work by Burg and Jaynes on the maximum entropy method. In the present paper we present a new fast algorithm in the general case (i.e., for general Gaussian priors) and show that for priors with a specific structure the solution can be given in closed form.Comment: 17 pages, 4 figure

    The Euler anomaly and scale factors in Liouville/Toda CFTs

    Get PDF
    The role played by the Euler anomaly in the dictionary relating sphere partition functions of four dimensional theories of class S\mathcal{S} and two dimensional nonrational CFTs is clarified. On the two dimensional side, this involves a careful treatment of scale factors in Liouville/Toda correlators. Using ideas from tinkertoy constructions for Gaiotto duality, a framework is proposed for evaluating these scale factors. The representation theory of Weyl groups plays a critical role in this framework.Comment: 55 pages, 16 figures; v2:fixed referencing & typos ; v3: argument about scale factors in Liouville/Toda now phrased in terms of stripped correlators, leading to a sharper conjecture (earlier version had some inaccurate statements). Presentation improved, typos fixed, refs added. I thank the anonymous referee for comments. Version accepted for publication in JHE

    What and How do Cancer Systems Biologists Explain?

    Get PDF
    In this article, we argue, first, that there are very different research projects that fall under the heading of “systems biology of cancer.” While they share some general features, they differ in their aims and theoretical commitments. Second, we argue that some explanations in systems biology of cancer are concerned with properties of signaling networks (such as robustness or fragility) and how they may play an important causal role in patterns of vulnerability to cancer. Further, some systems biological explanations are compelling illustrations of how “top-down” and “bottom-up” approaches to the same phenomena may be integrated

    Exponential Networks and Representations of Quivers

    Full text link
    We study the geometric description of BPS states in supersymmetric theories with eight supercharges in terms of geodesic networks on suitable spectral curves. We lift and extend several constructions of Gaiotto-Moore-Neitzke from gauge theory to local Calabi-Yau threefolds and related models. The differential is multi-valued on the covering curve and features a new type of logarithmic singularity in order to account for D0-branes and non-compact D4-branes, respectively. We describe local rules for the three-way junctions of BPS trajectories relative to a particular framing of the curve. We reproduce BPS quivers of local geometries and illustrate the wall-crossing of finite-mass bound states in several new examples. We describe first steps toward understanding the spectrum of framed BPS states in terms of such "exponential networks."Comment: 82 pages, 60 figures, typos fixe

    Strategic retirement reform: identifying the broader strategic effects from changes in human capital

    Get PDF
    This project seeks to understand the changes in the decision-making process to stay or leave the military upon adoption of a defined contribution retirement system, and the potential implications of human capital that might follow. Multiple theses have been written regarding potential cost savings of a defined contribution plan and how a change of this nature could affect military personnel retention rates. This project differs from other research in the field in that we assume the Department of Defense will shift the retirement compensation away from a pension system and 20-year vesting of benefits in the near future. This report focuses on the decision-making process that service members use and the potential implications for the services that might follow under a DC plan, and how that decision-making process might change. Specifically, we utilize the unfolding model of voluntary turnover to assess the decision-making process for military personnel and assess the potential impacts from a voluntary turnover, retention, and Human Capital Theory perspective.http://archive.org/details/strategicretirem1094527893Captain, United States Marine CorpsLieutenant, United States NavyApproved for public release; distribution is unlimited
    corecore