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Strategic, tactical decisions and information in Rapid Manufacturing supply chain
The efficiency and agility of its supply chain is vital to the commercial success of any product. Sharing strategic and tactical information effectively within the supply chain is often a key factor in achieving this goal. This paper proposes a framework to identify strategic, tactical decisions and information. The framework is used to conduct a sector based analysis of the Rapid Manufacturing (RM) industry. The decisions and information identified include amongst others various supply chain strategies and technical information
Modeling microscopic swimmers at low Reynolds number
We employ three numerical methods to explore the motion of low Reynolds
number swimmers, modeling the hydrodynamic interactions by means of the Oseen
tensor approximation, lattice Boltzmann simulations and multiparticle collision
dynamics. By applying the methods to a three bead linear swimmer, for which
exact results are known, we are able to compare and assess the effectiveness of
the different approaches. We then propose a new class of low Reynolds number
swimmers, generalized three bead swimmers that can change both the length of
their arms and the angle between them. Hence we suggest a design for a
microstructure capable of moving in three dimensions. We discuss multiple bead,
linear microstructures and show that they are highly efficient swimmers. We
then turn to consider the swimming motion of elastic filaments. Using
multiparticle collision dynamics we show that a driven filament behaves in a
qualitatively similar way to the micron-scale swimming device recently
demonstrated by Dreyfus et al.Comment: 12 pages, 10 figure
Libraries Respond to Mobile Ubiquity: Research and Assessment of Mobile Device Usage Trends for Academic and Medical Libraries
The authors consider trends in mobile device usage for the Internet as a whole, for EBSCO Discovery Service across all client libraries, and at two specific libraries: Preston Medical Library, serving the University of Tennessee (UT) Graduate School of Medicine and UT Medical Center, and the Joyner Library at East Carolina University, serving students and faculty on the main campus. Librarians at Preston Medical Library conducted a survey to determine which mobile devices, platforms, and apps were used by their patrons in 2012. East Carolina University piloted an iPad and e-reader lending program in 2010–2011. The results of each are being used to guide service planning related to mobile applications, education, and support
Intrinsic neuronal dynamics predict distinct functional roles during working memory
Working memory (WM) is characterized by the ability to maintain stable representations over time; however, neural activity associated with WM maintenance can be highly dynamic. We explore whether complex population coding dynamics during WM relate to the intrinsic temporal properties of single neurons in lateral prefrontal cortex (lPFC), the frontal eye fields (FEF), and lateral intraparietal cortex (LIP) of two monkeys (Macaca mulatta). We find that cells with short timescales carry memory information relatively early during memory encoding in lPFC; whereas long-timescale cells play a greater role later during processing, dominating coding in the delay period. We also observe a link between functional connectivity at rest and the intrinsic timescale in FEF and LIP. Our results indicate that individual differences in the temporal processing capacity predict complex neuronal dynamics during WM, ranging from rapid dynamic encoding of stimuli to slower, but stable, maintenance of mnemonic information.Biotechnology and Biological Sciences Research Council (Great Britain) (BB/M010732/1)United States. Office of Naval Research (N00014-14-1-0681)National Institute of Mental Health (U.S.) (R00MH092715)National Institute of Mental Health (U.S.) (R37MH087027)Massachusetts Institute of Technology. Picower Innovation FundUnited States. Office of Naval Research. Multidisciplinary University Research Initiative (grant N00014-16-1-2832)National Institute for Health Research (Great Britain). Wellcome Trust (203139/Z/16/Z
Global Stability of a Premixed Reaction Zone (Time-Dependent Liñan’s Problem)
Global stability properties of a premixed, three-dimensional reaction zone are considered. In the nonadiabatic case (i.e., when there is a heat exchange between the reaction zone and the burned gases) there is a unique, spatially one-dimensional steady state that is shown to be unstable (respectively, asymptotically stable) if the reaction zone is cooled (respectively, heated) by the burned mixture. In the adiabatic case, there is a unique (up to spatial translations) steady state that is shown to be stable. In addition, the large-time asymptotic behavior of the solution is analyzed to obtain sufficient conditions on the initial data for stabilization. Previous partial numerical results on linear stability of one-dimensional reaction zones are thereby confirmed and extended
Feedback-optimized parallel tempering Monte Carlo
We introduce an algorithm to systematically improve the efficiency of
parallel tempering Monte Carlo simulations by optimizing the simulated
temperature set. Our approach is closely related to a recently introduced
adaptive algorithm that optimizes the simulated statistical ensemble in
generalized broad-histogram Monte Carlo simulations. Conventionally, a
temperature set is chosen in such a way that the acceptance rates for replica
swaps between adjacent temperatures are independent of the temperature and
large enough to ensure frequent swaps. In this paper, we show that by choosing
the temperatures with a modified version of the optimized ensemble feedback
method we can minimize the round-trip times between the lowest and highest
temperatures which effectively increases the efficiency of the parallel
tempering algorithm. In particular, the density of temperatures in the
optimized temperature set increases at the "bottlenecks'' of the simulation,
such as phase transitions. In turn, the acceptance rates are now temperature
dependent in the optimized temperature ensemble. We illustrate the
feedback-optimized parallel tempering algorithm by studying the two-dimensional
Ising ferromagnet and the two-dimensional fully-frustrated Ising model, and
briefly discuss possible feedback schemes for systems that require
configurational averages, such as spin glasses.Comment: 12 pages, 14 figure
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