12,900 research outputs found

    \u3cem\u3eYeaton and Others, Claimants of the Schooner General Pinkney and Cargo v. The United States\u3c/em\u3e: The Case, the History, and the Impact

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    On February 28, 1806 Congress passed an embargo against any part of St. Domingo not in possession by the French Government. There was much debate regarding the embargo and the international politics regarding the Haitian Revolution. On August 23, 1806 the Schooner General Pinkney, owned by William Yeaton set sail from the port of Alexandria for St. Jago de Cuba, but instead went to the prohibited port of Cape Francois, St. Domingo. In addition to this ship, another ship owned by William Yeaton, the Schooner Betsey and Charlotte also took the same course on September 23, 1806. Both were held in violation of the embargo, but only the Betsey and Charlotte was condemned. This paper will examine the history behind the embargo, the cases of the General Pinkney and the Betsey and Charlotte, and the effects the General Pinkney had on America’s legal field

    Decoherent Histories and Non-adiabatic Quantum Molecular Dynamics

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    The role of quantum coherence loss in mixed quantum-classical dynamical systems is explored in the context of the theory of quantum decoherence introduced recently by Bittner and Rossky. (J. Chem. Phys. {\bf 103}, 8130 (1995)). This theory, which is based upon the consistent histories interpretation of quantum mechanics, introduces decoherence in the quantum subsystem by carefully considering the relevant time and length scales over which one must consider the effects of phase interference between alternative histories of the classical subsystem. Such alternative histories are an integral part of any quantum-classical computational scheme which employ transitions between discrete quantum states; consequently, the coherences between alternative histories have a profound effect on the transition probability between quantum states. In this paper, we review the Bittner-Rossky theory and detail a computational algorithm suitable for large-scale quantum molecular dynamics simulations which implements this theory. Application of the algorithm towards the relaxation of a photoexcited aqueous electron compare well to previous estimates of the excited state survival time as well as to the experimental measurements.Comment: 22 pages, 3 figure

    Aspectual interpretation of early verb forms in german

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    In the present paper, I will argue that even in a language like German, where the verb system does not contain a grammaticized aspect distinction, aspectual features do underlie the early form-function-mapping of verb forms in L1-acquisition. Furthermore, it will be argued that it is not only past tense forms that may receive an aspectual interpretation in early child language but also other forms of the verbal input. In the case of German, these are the forms of the present tense paradigm and the past participle. Showing and discussing various piecesof evidence for this assumption should strengthen the "aspect before tense" or "primacy of aspect" hypothesis. In general, the paper aims at a deeper understanding of the hierarchical relation between tense and aspect whereby aspect is the basic category and, therefore, aspectual features are the inevitable starting point of the acquisition of grammar

    An effective Hamiltonian approach for Donor-Bridge-Acceptor electronic transitions: Exploring the role of bath memory

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    We present here a formally exact model for electronic transitions between an initial (donor) and final (acceptor) states linked by an intermediate (bridge) state. Our model incorporates a common set of vibrational modes that are coupled to the donor, bridge, and acceptor states and serves as a dissipative bath that destroys quantum coherence between the donor and acceptor. Taking the memory time of the bath as a free parameter, we calculate transition rates for a heuristic 3-state/2 mode Hamiltonian system parameterized to represent the energetics and couplings in a typical organic photovoltaic system. Our results indicate that if the memory time of the bath is of the order of 10-100 fs, a two-state kinetic (i.e., incoherent hopping) model will grossly underestimate overall transition rate.Comment: 9 pages, 2 figure

    Dimension-Based Subscription Pruning for Publish/Subscribe Systems

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    Subscription pruning has been proven as valuable routing optimization for Boolean subscriptions in publish/ subscribe systems. It aims at optimizing subscriptions independently of each other and is thus applicable for all kinds of subscriptions regardless of their individual and collective structures. The original subscription pruning approach tries to optimize the event routing process based on the expected increase in network load. However, a closer look at pruning-based routing reveals its further applicability to optimizations in respect to other dimensions. In this paper, we introduce and investigate subscription pruning based on three dimensions of optimization: network load, memory usage, and system throughput. We present the algorithms to perform prunings based on these dimensions and discuss the results of a series of practical experiments. Our analysis reveals the advantages and disadvantages of the different dimensions of optimization and allows conclusions about the suitability of dimension-based pruning for different application requirements
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