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The Political Replacement Effect in a Kinetic Model of Social Dynamics with Phase Transition

Abstract

The political replacement effect is an interesting socio-political hypothesis introduced by Acemoglu and Robinson and statistically tested. It may determine, under some conditions, the phenomenon of innovation blocking, possibly leading to economic backwardness in a society. In a previous paper, we have introduced a kinetic model with stochastic evolutive game-type interactions, analyzing the relationship between the level of political competition in a society and the degree of economic liberalization. In the present paper we model we model the possibility of having a sort of phase transition occurring in the system when the phenomenon of blocking of the introduction of technological innovation, intended in a broad sense, appears. Crossing a critical point, the rules of interactions change by means of slightly different transition probabilities nevertheless determining very significant differences in the resulting long-term solutions.

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“Phase transition” between Confrontation and Dialogue in the Light of the Concept of the Unity Charism

Abstract

In the twenties of the last century the process of building a new type of philosophical culture began, based on the sensitivity towards another person, the recognition of values and dignity of the person and the search for platforms of dialogue and compromise between people. However, it did not gain a broad social resonance. The 20th Century became the scene of the triumph of totalitarianisms, based on the idea of collectivism and marked by the contempt towards the individual, his rights and needs. In the post-war reality environments favouring the humanization of the culture of coexistence earned a voice, but they too did not manage to divert the tendency towards building a bureaucratic and technocratic order. In this kind of system, the person feels reduced to his instrumental functions, and the dialogue submerged in the world of humanistic values becomes a distant and unequalled dream. This text undertakes the problem of the conditions which must be met in order for the tendency towards dialogue and mutual respect to prevail over the hostile, confrontational approach, which characterizes many contemporary social environments. The author suggests that we refer to the analogy with the thermodynamics phenomenon, phase transition, and consider the notion of spiritual energy (the analogue of the physical term enthalpy) as an agent regulating the internal disposition of the individual to “freeze” or “thaw” relations with his fellow human beings. The key thesis is that the most important source of energy indispensable to move from confrontation to dialogue lies in the resources of religious experience- the openness to the grace flowing from the transcendental reality, and the guides on the path to discovering this source are the witnesses of faith- among them the spiritual heirs of Chiara Lubich’s charism.

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Mechanical Behaviour and Phase Transition Mechanisms of a Shape Memory Alloy by Means of a Novel Analytical Model

Abstract

The aim of the present paper is to examine both the fatigue behaviour and the phase transition mechanisms of an equiatomic pseudo-elastic NiTi Shape Memory Alloy through cyclic tests (up to 100 loading cycles). More precisely, miniaturised dog-bone specimens are tested by using a customised testing machine and the contents of both austenite and martensite phase are experimentally measured by means of X-Ray diffraction (XRD) analyses. On the basis of such experimental results in terms of martensite content, an analytical model is here formulated to correlate the stress-strain relationship to the phase transition mechanisms. Finally, a validation of the present model by means of experimental data pertaining the stress-strain relationship is performed.

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Size effect and dielectric properties of NH4H2PO4 — porous glass composites

] Samara G.A., Phys. Rev. Lett. 27 (1971), 103–106. http://dx.doi.org/10.1103/PhysRevLett.27.103 [5] Tarnavich V., Korotkov L., Karaeva O., Naberezhnov A., Rysiakiewicz-pasek E., Opt. Appl. XL, 2 (2010), 305. [6] Marciniszyn T., Poprawski R., Komar J., Sieradzki A., Phase Transitions 83 (2010), 909. http://dx.doi.org/10.1080/01411594.2010.509593 [7] Rysiakiewicz-Pasek E., Lukaszewski P., Bogdanska J., Opt. Appl. 30 (2000), 173. [8] Dziedzic J., Poprawski R

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Electronic and structural properties of rare earth pnictides

NaCl-type (B1) structure and under high pressure they show a first order structural phase transition to CsCl-type (B2) structure at a normal temperature and pressure. Only some theoretical papers and a little experimental work have been dedicated to the study of structural and electronic properties of this series of rare earth pnictides. Therefore, the knowledge of high pressure behavior is important in understanding the properties of these compounds. Some structural and elastic properties of (XBi; X = Am, Cf) were studied in previous years [10 , 11] . The

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Use of a Phase Transition Concept for Traffic Flow Condition Estimation

References 1. Larin, O.N. (2007). Methodology of organization and the functioning of regional transportation systems. Chelyabinsk: SUSU. - 205 p. 2. Daganzo, C.F. (1999). Possible explanations of phase transitions in highway traffic / C.F. Daganzo, MJ. Cassidy, R.L. Bertini, Transportation Research, Part A, V. 33, pp. 365-379. 3. Silyanov, V.V. (1977). Theory of traffic flows in road design and the organization of traffic. Moscow: Transport. 303 p. 4. Daganzo, C.F. (2002). A behavioral theory of multi-lane traffic flow. Part I: Long homogeneous

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VO2(B) conversion to VO2(A) and VO2(M) and their oxidation resistance and optical switching properties

. Table 1 The crystallography data of some important types of VO 2 polymorph. Phase T c [°C] T c : phase transition temperature; Cs: Crystal system; Sg: Space group. Cs T c : phase transition temperature; Cs: Crystal system; Sg: Space group. Sg T c : phase transition temperature; Cs: Crystal system; Sg: Space group. a [Å] b [Å] c [Å] β (°) Ref. VO 2 (B) — Monoclinic C2/m 12.03 3.693 6.420 106.6 [17] VO 2 (M) 68 Monoclinic P2 1 /c 5.743 4.157 5.375 122.6 [18] VO 2 (R) 68 Tetragonal P4

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A facile synthesizing method of vanadium dioxide by pyrolyzing ammonium metavanadate

Abstract

A facile process was developed for synthesizing vanadium dioxide (VO2) by pyrolyzing ammonium metavanadate (NH4VO3) in nitrogen flow. The process was designed on the base of thermodynamic modeling of chemical reaction and thermal analyzing of NH4VO3 pyrogenation in N2 gas, and optimized by experiments. X-ray diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) were applied to characterizing the product VO2. Thermo-gravimetric analysis (TG) and DSC were used for analyzing the process of NH4VO3 pyrogenation. The experimental results indicated that VO2 microcrystal particles were successfully synthesized. The product VO2 presents two kinds of micro morphologies, torispherical and pentagonal prism. The phase transition mainly takes place at 338.4 K and 341.9 K. The average enthalpy of the phase transition is 28.82 J/g.

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Structural elastic and thermal properties of SrxCd1−x O mixed compounds — a theoretical approach

Abstract

In the present paper, the structural and mechanical properties of alkaline earth oxides mixed compound SrxCd1−x O (0 ≤ x ≤ 1) under high pressure have been reported. An extended interaction potential (EIP) model, including the zero point vibrational energy effect, has been developed for this study. Phase transition pressures are associated with a sudden collapse in volume. Phase transition pressure and associated volume collapses [ΔV (Pt)/V(0)] calculated from this approach are in good agreement with the experimental values for the parent compounds (x = 0 and x = 1). The results for the mixed crystal counterparts are also in fair agreement with experimental data generated from the application of Vegard’s law to the data for the parent compounds.

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Phase transition in a system of random sparse Boolean equations

ABSTRACT

Many problems, including algebraic cryptanalysis, can be transformed to a problem of solving a (large) system of sparse Boolean equations. In this article we study 2 algorithms that can be used to remove some redundancy from such a system: Agreeing, and Syllogism method. Combined with appropriate guessing strategies, these methods can be used to solve the whole system of equations. We show that a phase transition occurs in the initial reduction of the randomly generated system of equations. When the number of (partial) solutions in each equation of the system is binomially distributed with probability of partial solution p, the number of partial solutions remaining after the initial reduction is very low for p’s below some threshold pt, on the other hand for p > pt the reduction only occurs with a quickly diminishing probability.

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