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    Statistical evaporation of rotating clusters. IV. Alignment effects in the dissociation of nonspherical clusters

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    Unimolecular evaporation in rotating, non-spherical atomic clusters is investigated using Phase Space Theory in its orbiting transition state version. The distributions of the total kinetic energy release epsilon_tr and the rotational angular momentum J_r are calculated for oblate top and prolate top main products with an arbitrary degree of deformation. The orientation of the angular momentum of the product cluster with respect to the cluster symmetry axis has also been obtained. This statistical approach is tested in the case of the small 8-atom Lennard-Jones cluster, for which comparison with extensive molecular dynamics simulations is presented. The role of the cluster shape has been systematically studied for larger, model clusters in the harmonic approximation for the vibrational densities of states. We find that the type of deformation (prolate vs. oblate) plays little role on the distributions and averages of epsilon_tr and J_r except at low initial angular momentum. However, alignment effects between the product angular momentum and the symmetry axis are found to be significant, and maximum at some degree of oblateness. The effects of deformation on the rotational cooling and heating effects are also illustrated.Comment: 15 pages, 9 figure

    A multiplicative potential approach to solutions for cooperative TU-games

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    Concerning the solution theory for cooperative games with transferable utility, it is well-known that the Shapley value is the most appealing representative of the family of (not necessarily efficient) game-theoretic solutions with an additive potential representation. This paper introduces a new solution concept, called Multiplicativily Proportional (MPMP) value, that can be regarded as the counterpart of the Shapley value if the additive potential approach to the solution theory is replaced by a multiplicative potential approach in that the difference of two potential evaluations is replaced by its quotient. One out of two main equivalence theorems states that every solution with a multiplicative potential representation is equivalent to this specifically chosen efficient value in that the solution of the initial game coincides with the MPMP value of an auxiliary game. The associated potential function turns out to be of a multiplicative form (instead of an additive form) with reference to the worth of all the coalitions. The second equivalence theorem presents four additional characterizations of solutions that admit a multiplicative potential representation, e.g., preservation of discrete ratios or path independence

    Are the anti-globalists right? Gains-from-trade without a Walrasian auctioneer

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    We examine whether the "fear" of globalisation can be rationalised by economic theory. To do so, we depart from the standard AD/AS (partial) equilibrium model where the coordinational role of the Auctioneer is substituted by an implementation device based on learning (Guesnerie, 1992). By endowing producers with a learning ability to forecast market prices, individual profit-maximizing production decisions become interdependent in a strategic sense (strategic substitutes). Performing basic comparative statics exercises, we show that "competitiveness" matters in a precise sense: as foreign producers gain access to the home market, home producers' ability to forecast market prices is undermined, so being their ability to forecast the profit consequences of their production decisions. When performing a standard open economy exercise in such a framework, we show that the existence of standard efficiency gains - due to the increase in competition (or spatial price stabilization) - is traded-off against coordination upon the welfare enhancing free-trade equilibrium (stabilizing price expectations). Therefore, we identify a new rationale for an exogenous price intervention in open economy targeting coordination, to allow trading countries to fully reap the benefits from trade. We illustrate this point showing that classical measures evaluating ex-ante the desirability of economic integration (net welfare gains) do not always advice integration between two expectationally stable economies

    Where’s the Remote? Face Time, Remote Work, and Implications for Performance Management

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    [Excerpt] Yahoo CEO Marissa Mayer’s ban on telecommuting and the subsequent uproar over that decision highlights the need for a deeper understanding of the impact of remote work. Although it would prove comforting to assert that the peer-reviewed findings of the social and managerial sciences are in accord as to the benefits of telework in the face of the discord among organizational leaders, the reality is that little such agreement exists. Consequently, the proponents of remote work in management and HR are given little support in defense of such potentially large-scale initiatives or interventions. To that end, what follows is a discussion of the relative merits of remote work, as compared to the traditional conception of work, and an exploration of the practical implications for HR practitioners in performance management and employee evaluation