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Displaying article 1-14
p. 1325-1343
Received: 25 February 2010; in revised form: 24 March 2010 / Accepted: 28 April 2010 / Published: 26 May 2010
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| Download PDF Full-text (281 KB) Abstract: Culture can be viewed as the means by which a society can live in its surroundings by acquiring and consuming free energy. This naturalistic notion assumes that everything can be valued in terms of energy, hence also social changes can be described as natural processes that are influenced by the 2nd Law of Thermodynamics. This universal law, when formulated as an equation of motion, reveals that societies emerge, evolve and eventually extinguish after tapping, exploiting and finally depleting their resources, which we can say are ultimately valued in energetic terms. The analysis reveals that trajectories of societies are, however, inherently non-integrable, i.e. , unpredictable in detail because free energy as the driving force, being finite, is inseparable from the flows of energy. Nonetheless, the universal tendency to diminish energy differences within a system and with respect to its surroundings in the least possible time gives rise to highly economical but seemingly immaterial means of energy transduction that associate with cultural codes, habits, traditions, taboos and values. Moreover, cultural naturalism clarifies that identities develop and mature in interactions, and that class structure results from the quest for maximum entropy partition. While social changes in complex societies are inherently intractable, the profound principle allows us to recognize universal tendencies in diverse cultural characteristics, and to rationalize prospects for the future.
p. 1344
Received: 17 May 2010 / Published: 27 May 2010
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| Download PDF Full-text (64 KB) Abstract: We just became aware that the article [1] published in Entropy 2009 contains a false reference . [...]
p. 1345-1390
Received: 30 March 2010; in revised form: 26 April 2010 / Accepted: 8 May 2010 / Published: 28 May 2010
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| Download PDF Full-text (964 KB) Abstract: The paper discusses the concept of entropy as applied to friction and wear. Friction and wear are classical examples of irreversible dissipative processes, and it is widely recognized that entropy generation is their important quantitative measure. On the other hand, the use of thermodynamic methods in tribology remains controversial and questions about the practical usefulness of these methods are often asked. A significant part of entropic tribological research was conducted in Russia since the 1970s. Surprisingly, many of these studies are not available in English and still not well known in the West. The paper reviews various views on the role of entropy and self-organization in tribology and it discusses modern approaches to wear and friction, which use the thermodynamic entropic method as well as the application of the mathematical concept of entropy to the dynamic friction effects (e.g., the running-in transient process, stick-slip motion, etc .) and a possible connection between the thermodynamic and information approach. The paper also discusses non-equilibrium thermodynamic approach to friction, wear, and self-healing. In general, the objective of this paper is to answer the frequently asked question “is there any practical application of the thermodynamics in the study of friction and wear?” and to show that the thermodynamic methods have potential for both fundamental study of friction and wear and for the development of new (e.g., self-lubricating) materials.
p. 1391-1417
Received: 28 April 2010 / Accepted: 28 May 2010 / Published: 28 May 2010
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| Download PDF Full-text (3829 KB) Abstract: The influence of an external oriented magnetic field on entropy generation in natural convection for air and liquid gallium is numerically studied in steady-unsteady states by solving the mass, the momentum and the energy conservation equations. Entropy generation depends on five parameters which are: the Prandtl number, the irreversibility coefficients, the inclination angle of the magnetic field, the thermal Grashof and the Hartmann numbers. Effects of these parameters on total and local irreversibilities as well as on heat transfer and fluid flow are studied. It was found that the magnetic field tends to decrease the convection currents, the heat transfer and entropy generation inside the enclosure. Influence of inclination angle of the magnetic field on local irreversibility is then studied.
p. 1418-1439
Received: 30 March 2010; in revised form: 21 May 2010 / Accepted: 31 May 2010 / Published: 1 June 2010
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| Download PDF Full-text (159 KB) Abstract: The friction and wear phenomena appear due to contact and relative motion between two solids. The evolution of contact conditions depends on loading conditions and mechanical behaviours. The wear phenomena are essentially characterized by a matter loss. Wear and friction are in interaction due to the fact that particles are detached from the solids. A complex medium appears as an interface having a strong effect on the friction condition. The purpose of this paper is to describe such phenomena taking account of different scales of modelization in order to derive some macroscopic laws. A thermodynamical approach is proposed and models of wear are analysed in this framework where the separation between the dissipation due to friction and that due to wear is made. Applications on different cases are presented.
p. 1440-1483
Received: 9 May 2010 / Accepted: 3 June 2010 / Published: 9 June 2010
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| Download PDF Full-text (2596 KB) Abstract: In dyadic communication, both interlocutors adapt to each other linguistically, that is, they align interpersonally . In this article, we develop a framework for modeling interpersonal alignment in terms of the structural similarity of the interlocutors’ dialog lexica. This is done by means of so-called two-layer time-aligned network series , that is, a time-adjusted graph model. The graph model is partitioned into two layers, so that the interlocutors’ lexica are captured as subgraphs of an encompassing dialog graph. Each constituent network of the series is updated utterance-wise. Thus, both the inherent bipartition of dyadic conversations and their gradual development are modeled. The notion of alignment is then operationalized within a quantitative model of structure formation based on the mutual information of the subgraphs that represent the interlocutor’s dialog lexica. By adapting and further developing several models of complex network theory, we show that dialog lexica evolve as a novel class of graphs that have not been considered before in the area of complex (linguistic) networks. Additionally, we show that our framework allows for classifying dialogs according to their alignment status. To the best of our knowledge, this is the first approach to measuring alignment in communication that explores the similarities of graph-like cognitive representations.
p. 1484-1498
Received: 12 April 2010 / Accepted: 20 May 2010 / Published: 10 June 2010
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| Download PDF Full-text (480 KB) Abstract: Determining the distributions of size and velocity of droplets formed at the end of primary breakup region is followed in this paper. The droplet formation stage at the end of primary breakup is random and stochastic and it can be modeled by statistical means based on the maximum entropy principle (MEP). The MEP formulation predicts the atomization process while satisfying constraint equations based on conservations of mass, momentum and energy. This model is capable of considering drag force on produced droplets through gas-liquid interaction using new approach. The model prediction is compared favorably with the experimentally measured size and velocity distributions of droplets for sprays produced by the two nozzles of considerably different geometries and shows satisfactory agreement.
p. 1499-1513
Received: 10 April 2010 / Accepted: 27 May 2010 / Published: 10 June 2010
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| Download PDF Full-text (392 KB) Abstract: In this paper, the energy distributions of various noises following normal, log-normal and Pearson-III distributions are first described quantitatively using the wavelet energy entropy (WEE), and the results are compared and discussed. Then, on the basis of these analytic results, a method for use in choosing the decomposition level (DL) in wavelet threshold de-noising (WTD) is put forward. Finally, the performance of the proposed method is verified by analysis of both synthetic and observed series. Analytic results indicate that the proposed method is easy to operate and suitable for various signals. Moreover, contrary to traditional white noise testing which depends on “autocorrelations”, the proposed method uses energy distributions to distinguish real signals and noise in noisy series, therefore the chosen DL is reliable, and the WTD results of time series can be improved.
p. 1514-1531
Received: 19 April 2010; in revised form: 3 June 2010 / Accepted: 5 June 2010 / Published: 14 June 2010
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| Download PDF Full-text (718 KB) Abstract: The excessive compensation packages of CEOs of U.S. corporations in recent years have brought to the foreground the issue of fairness in economics. The conventional wisdom is that the free market for labor, which determines the pay packages, cares only about efficiency and not fairness. We present an alternative theory that shows that an ideal free market environment also promotes fairness, as an emergent property resulting from the self-organizing market dynamics. Even though an individual employee may care only about his or her salary and no one else’s, the collective actions of all the employees, combined with the profit maximizing actions of all the companies, in a free market environment under budgetary constraints, lead towards a more fair allocation of wages, guided by Adam Smith’s invisible hand of self-organization. By exploring deep connections with statistical thermodynamics, we show that entropy is the appropriate measure of fairness in a free market environment which is maximized at equilibrium to yield the lognormal distribution of salaries as the fairest inequality of pay in an organization under ideal conditions.
p. 1532-1568
Received: 26 April 2010 / Accepted: 1 June 2010 / Published: 14 June 2010
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| Download PDF Full-text (523 KB) Abstract: In this paper, we extend and overview wide families of Alpha-, Beta- and Gamma-divergences and discuss their fundamental properties. In literature usually only one single asymmetric (Alpha, Beta or Gamma) divergence is considered. We show in this paper that there exist families of such divergences with the same consistent properties. Moreover, we establish links and correspondences among these divergences by applying suitable nonlinear transformations. For example, we can generate the Beta-divergences directly from Alpha-divergences and vice versa. Furthermore, we show that a new wide class of Gamma-divergences can be generated not only from the family of Beta-divergences but also from a family of Alpha-divergences. The paper bridges these divergences and shows also their links to Tsallis and Rényi entropies. Most of these divergences have a natural information theoretic interpretation.
p. 1569-1580
Received: 16 April 2010; in revised form: 3 June 2001 / Accepted: 11 June 2010 / Published: 14 June 2010
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| Download PDF Full-text (172 KB) Abstract: This paper develops a semi-parametric, Information-Theoretic method for estimating parameters for nonlinear data generated under a sample selection process. Considering the sample selection as a set of inequalities makes this model inherently nonlinear. This estimator (i) allows for a whole class of different priors, and (ii) is constructed as an unconstrained, concentrated model. This estimator is easy to apply and works well with small or complex data. We provide a number of explicit analytical examples for different priors’ structures and an empirical example.
p. 1581-1611
Received: 8 April 2010; in revised form: 27 May 2010 / Accepted: 31 May 2010 / Published: 14 June 2010
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| Download PDF Full-text (877 KB) Abstract: In his 1985 article (“Projection pursuit”), Huber demonstrates the interest of his method to estimate a density from a data set in a simple given case. He considers the factorization of density through a Gaussian component and some residual density. Huber’s work is based on maximizing Kullback–Leibler divergence. Our proposal leads to a new algorithm. Furthermore, we will also consider the case when the density to be factorized is estimated from an i.i.d. sample. We will then propose a test for the factorization of the estimated density. Applications include a new test of fit pertaining to the elliptical copulas.
p. 1612-1631
Received: 4 May 2010; in revised form: 17 June 2010 / Accepted: 18 June 2010 / Published: 23 June 2010
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| Download PDF Full-text (676 KB) Abstract: Using the graphical calculus and integration techniques introduced by the authors, we study the statistical properties of outputs of products of random quantum channels for entangled inputs. In particular, we revisit and generalize models of relevance for the recent counterexamples to the minimum output entropy additivity problems. Our main result is a classification of regimes for which the von Neumann entropy is lower on average than the elementary bounds that can be obtained with linear algebra techniques.
p. 1632-1652
Received: 1 March 2010; in revised form: 30 May 2010 / Accepted: 18 June 2010 / Published: 23 June 2010
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| Download PDF Full-text (293 KB) Abstract: We review a general framework of pressure effects on the structures formed by entropically driven self-assembly (for example, denaturation of proteins from their native structure and dissociation of ordered structure of the amyloid fibril occur at high pressures). In the framework, the translational entropy of water is an essential factor. Our findings are as follows: at low pressures, the structures almost minimizing the excluded volume (EV) generated for water molecules are stable. On the other hand, at high pressures, the structures possessing the largest possible water-accessible surface area together with sufficiently small EV become more stable. These characteristics are consistent with experimental observations.
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