6,244 research outputs found

    Level 2.5 large deviations for continuous time Markov chains with time periodic rates

    Full text link
    We consider an irreducible continuous time Markov chain on a finite state space and with time periodic jump rates and prove the joint large deviation principle for the empirical measure and flow and the joint large deviation principle for the empirical measure and current. By contraction we get the large deviation principle of three types of entropy production flow. We derive some Gallavotti-Cohen duality relations and discuss some applications.Comment: 37 pages. corrected versio

    Towards a nonequilibrium thermodynamics: a self-contained macroscopic description of driven diffusive systems

    Full text link
    In this paper we present a self-contained macroscopic description of diffusive systems interacting with boundary reservoirs and under the action of external fields. The approach is based on simple postulates which are suggested by a wide class of microscopic stochastic models where they are satisfied. The description however does not refer in any way to an underlying microscopic dynamics: the only input required are transport coefficients as functions of thermodynamic variables, which are experimentally accessible. The basic postulates are local equilibrium which allows a hydrodynamic description of the evolution, the Einstein relation among the transport coefficients, and a variational principle defining the out of equilibrium free energy. Associated to the variational principle there is a Hamilton-Jacobi equation satisfied by the free energy, very useful for concrete calculations. Correlations over a macroscopic scale are, in our scheme, a generic property of nonequilibrium states. Correlation functions of any order can be calculated from the free energy functional which is generically a non local functional of thermodynamic variables. Special attention is given to the notion of equilibrium state from the standpoint of nonequilibrium.Comment: 21 page

    Price Promotion for Emotional Impact

    Get PDF
    Managers and academics often think of price promotions merely as incentives that entice consumers to accept offers that they might not have considered otherwise. Yet the prospect of paying a lower price for a product of given quality can also discourage deliberation, in a sense "dumbing down" the purchase encounter by making it less consequential. The authors examine this possibility in a dual-system theory of consumer behavior. Specifically, they argue that price promotion lowers a consumer's motivation to exert mental effort, in which case purchase decisions are guided less by extensive information processing and more by a quicker, easier, strong conditioner of preference: affect. Field data from a large daily deal company and four controlled experiments support this idea and document its implications primarily for product choice, in turn providing insight into the form and cause of brand switching that manufacturers and retailers can leverage to improve the allocation of promotional budgets and category management

    Minimum dissipation principle in stationary non equilibrium states

    Full text link
    We generalize to non equilibrium states Onsager's minimum dissipation principle. We also interpret this principle and some previous results in terms of optimal control theory. Entropy production plays the role of the cost necessary to drive the system to a prescribed macroscopic configuration

    Quantitative analysis of Clausius inequality

    Full text link
    In the context of driven diffusive systems, for thermodynamic transformations over a large but finite time window, we derive an expansion of the energy balance. In particular, we characterize the transformations which minimize the energy dissipation and describe the optimal correction to the quasi-static limit. Surprisingly, in the case of transformations between homogeneous equilibrium states of an ideal gas, the optimal transformation is a sequence of inhomogeneous equilibrium states.Comment: arXiv admin note: text overlap with arXiv:1404.646

    Oregon Freight Data Mart

    Get PDF
    Increasing freight volumes are adding pressure to the Oregon transportation system. Monitoring the performance of the transportation system and freight movements is essential to guarantee the economic development of the region, the efficient allocation of resources, and the quality of life of all Oregonians. Freight data is expensive to collect and maintain. Confidentiality issues, the size of the datasets, and the complexity of freight movements are barriers that preclude the easy access and analysis of freight data. Data accessibility and integration is essential to ensure successful freight planning and consistency across regional partner agencies and planning organizations. In relation to Internet-based mapping technology in freight data collection and planning, the main objectives of this project are: (a) address implementation issues associated with data integration, (b) present a system architecture to leverage existing publically-available interfaces and web applications to accelerate product development and reduce costs, (c) describe an existing web-based mapping prototype and its capabilities, (d) state lessons learned and present suggestions to streamline the integration and visualization of freight data, and (e) discuss load-time and display quality issues associated with the visualization of transportation data on internet-based mapping applications. The strategies and methodologies described in this report are equally applicable to the display of areas such as states or counties as well as linear data such linear data such as highways, waterways, and railways. Despite data integration challenges, Internet-based mapping provides a cost effective and appealing tool to store, access, and communicate freight data as well as enhance our understanding of freight issues. Institutional barriers, not technology, are the most demanding hurdles to widely implementing a freight data web-based mapping application in the near future

    Large deviation approach to non equilibrium processes in stochastic lattice gases

    Full text link
    We present a review of recent work on the statistical mechanics of non equilibrium processes based on the analysis of large deviations properties of microscopic systems. Stochastic lattice gases are non trivial models of such phenomena and can be studied rigorously providing a source of challenging mathematical problems. In this way, some principles of wide validity have been obtained leading to interesting physical consequences.Comment: Extended version of the lectures given by G. Jona-Lasinio at the 9th Brazilian school of Probability, August 200
    • …
    corecore