4,274 research outputs found

    On the validity of entropy production principles for linear electrical circuits

    Full text link
    We discuss the validity of close-to-equilibrium entropy production principles in the context of linear electrical circuits. Both the minimum and the maximum entropy production principle are understood within dynamical fluctuation theory. The starting point are Langevin equations obtained by combining Kirchoff's laws with a Johnson-Nyquist noise at each dissipative element in the circuit. The main observation is that the fluctuation functional for time averages, that can be read off from the path-space action, is in first order around equilibrium given by an entropy production rate. That allows to understand beyond the schemes of irreversible thermodynamics (1) the validity of the least dissipation, the minimum entropy production, and the maximum entropy production principles close to equilibrium; (2) the role of the observables' parity under time-reversal and, in particular, the origin of Landauer's counterexample (1975) from the fact that the fluctuating observable there is odd under time-reversal; (3) the critical remark of Jaynes (1980) concerning the apparent inappropriateness of entropy production principles in temperature-inhomogeneous circuits.Comment: 19 pages, 1 fi

    Sulfur analysis of Bolu-Mengen lignite before and after microbiological treatment using reductive pyrolysis and gas chromatography/mass spectrometry

    Get PDF
    Atmospheric pressure-temperature programmed reduction coupled with on-line mass spectrometry (AP-TPR/MS) is used for the first time on microbiologically treated coal samples as a technique to monitor the degree of desulfurization of the various sulfur functionalities. The experimental procedure enables the identification of both organic and inorganic sulfur species present in the coal matrix. A better insight in the degradation of the coal matrix and the accompanying processes during the AP-TPR experiment is obtained by a quantitative differentiation of the sulfur. The determination of the sulfur balance for the reductive pyrolysis gives an overview of the side reactions and their relative contribution in the total process. The volatile sulfur species are unambiguously identified using AP-TPR off-line coupled with gas chromatography/mass spectrometry (GC/MS). In this way, fundamental mechanisms and reactions that occur during the reductive pyrolysis could be quantified, explaining the differences in AP-TPR recoveries. Therefore, this study gives a clearer view on the possibilities and limitations of AP-TPR as a technique to monitor sulfur functionalities in coal

    State of Utah v. Charles David Wright : Brief of Appellee

    Get PDF
    DEFENDANT\u27S APPEAL OF SENTENCE FOR ATTEMPTED POSSESSION OF AN INCENDIARY DEVICE, A THIRD DEGREE FELONY IN VIOLATION OF UTAH CODE ANN. §§ 76-4-102(3), 76-10-306(3) (1995), ENTERED BY THE THIRD JUDICIAL DISTRICT COURT, SALT LAKE COUNTY, UTAH, THE HONORABLE MICHAEL R. MURPHY, PRESIDING

    Display Blocks: a Set of Cubic Displays for Tangible, Multi-Perspective Data Exploration

    Get PDF
    This paper details the design and implementation of a new type of display technology. Display Blocks are a response to two major limitations of current displays: dimensional compression and physical-digital disconnect. Each Display Block consists of six organic light emitting diode (OLED) screens, arranged in a cubic form factor. We explore the possibilities that this type of display holds for data visualization, manipulation and exploration. To this end, we accompany our design with a set of initial applications that leverage the form factor of the displays. We hope that this work shows the promise of display technologies which use their form factor as a cue to understanding their content

    Display blocks: cubic displays for multi-perspective visualization

    Get PDF
    We propose the design, implementation and evaluation of a set of tangible cubic displays. This novel approach to display technology consists of arranging six organic light emitting diode screens in a cubic form factor. We explore the possibilities that this type of display holds for data visualization, manipulation and exploration. We are especially interested in exploring how the physicality of the screen can be perceived as a cue to better interpret its contents. To this end, we propose a series of applications that leverage the affordances of this technology.MIT Media Lab Consortiu

    Infinite volume limit of the Abelian sandpile model in dimensions d >= 3

    Full text link
    We study the Abelian sandpile model on Z^d. In dimensions at least 3 we prove existence of the infinite volume addition operator, almost surely with respect to the infinite volume limit mu of the uniform measures on recurrent configurations. We prove the existence of a Markov process with stationary measure mu, and study ergodic properties of this process. The main techniques we use are a connection between the statistics of waves and uniform two-component spanning trees and results on the uniform spanning tree measure on Z^d.Comment: First version: LaTeX; 29 pages. Revised version: LaTeX; 29 pages. The main result of the paper has been extended to all dimensions at least 3, with a new and simplyfied proof of finiteness of the two-component spanning tree. Second revision: LaTeX; 32 page

    Depression and sickness behavior are Janus-faced responses to shared inflammatory pathways

    Get PDF
    It is of considerable translational importance whether depression is a form or a consequence of sickness behavior. Sickness behavior is a behavioral complex induced by infections and immune trauma and mediated by pro-inflammatory cytokines. It is an adaptive response that enhances recovery by conserving energy to combat acute inflammation. There are considerable phenomenological similarities between sickness behavior and depression, for example, behavioral inhibition, anorexia and weight loss, and melancholic (anhedonia), physio-somatic (fatigue, hyperalgesia, malaise), anxiety and neurocognitive symptoms. In clinical depression, however, a transition occurs to sensitization of immuno-inflammatory pathways, progressive damage by oxidative and nitrosative stress to lipids, proteins, and DNA, and autoimmune responses directed against self-epitopes. The latter mechanisms are the substrate of a neuroprogressive process, whereby multiple depressive episodes cause neural tissue damage and consequent functional and cognitive sequelae. Thus, shared immuno-inflammatory pathways underpin the physiology of sickness behavior and the pathophysiology of clinical depression explaining their partially overlapping phenomenology. Inflammation may provoke a Janus-faced response with a good, acute side, generating protective inflammation through sickness behavior and a bad, chronic side, for example, clinical depression, a lifelong disorder with positive feedback loops between (neuro)inflammation and (neuro)degenerative processes following less well defined triggers
    corecore