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1.
《Physics letters. A》2020,384(26):126644
Asymmetric model of the quantum Stackelberg duopoly with complete information is more efficient than the symmetric one, since it can overcome the deficiencies encountered in the latter. However, the case of complete information is the simplest one in the game, the cases with incomplete information are more general and practical. Here, we will construct such an asymmetric model with incomplete information, where three different parameters γ, α, and ξ are introduced. The analysis shows that all the advantages of the asymmetric case with complete information are maintained. Besides that, one can better manage the market and optimize the total quantity of the product by choosing proper values of α and γ, according to the obtained uncertainty (ξ) of the incomplete information. What' more, it is also worth noticing that the new model is a general one which can degenerate to the case with complete information and that to the symmetric model.  相似文献   

2.
In this paper, we propose an agent-based model to study the impact of asymmetric information on market evolution. In each period, buyers and sellers are randomly matched. The condition for the transaction being performed depends on the comparison between valuations of buyers and sellers on the good they trade. We introduce cognitive capability to describe buyers’ valuation on a good and valuation ratio to reflect the gap between two kinds of traders’ valuations on the good. The market outcomes are sorted into four phases in the parameter space of these two variables. Computer simulations show us critical phenomena of phase transition. The model proposed herein is able to demonstrate how the asymmetry of information leads to the adverse selection effect. The model also explains the coexistence of low- and high-quality goods in a market with asymmetric information. We analyze the condition under which the asymmetry of information might not take its effect and find that the gap of valuations between buyers and sellers plays the key role.  相似文献   

3.
E. Romera  Á. Nagy 《Physics letters. A》2011,375(34):3066-3069
The Rényi entropies of the Dicke model are presented. This quantum-optical model describes a single-mode bosonic field interacting with an ensemble of N two-level atoms. There is a quantum phase transition in the N→∞ limit. It is shown that there is an abrupt change in the Rényi entropy of order β at the transition point. Around the critical value of the coupling strength λc the Rényi entropy is proportional to the logarithm of the characteristic length and diverges as ln|λcλ| for any order β. The pseudocapacity defined here in analogy with the heat capacity exhibits the phase transition. The critical exponent for the Dicke model is found to be 1 for any value of the parameter β.  相似文献   

4.
Considering the time scales of global information and personal reaction, we study the role of dynamic response time in the evolution of collective behavior in an evolving market. The insensitiveness to the market information makes the population cluster around a kind of extreme behavior, in which they always follow what happened last time, while a sensitive population tends to self-segregate into opposing groups. The average success rate R among all the agents is found to have a nonmonotonic dependence on the time scale parameter q. There exists a critical value below (above) which R decreases (increases) with the rise of q. Theoretical analyses demonstrate that the higher efficiency found in the market with an insensitive population is related to its predictability. In such a predictable market, the agents following current prediction have a higher winning probability than those rejecting it. Analytical calculations are in good agreement with numerical data.  相似文献   

5.
J.-F. Bercher 《Physics letters. A》2008,372(24):4361-4363
We indicate that in a maximum entropy setting, the thermodynamic β and the observation constraint are linked, so that fluctuations of the latter imposes fluctuations of the former. This gives an alternate viewpoint to ‘superstatistics’. While a Gamma model for fluctuations of the β parameter gives the so-called Tsallis distributions, we work out the case of a Gamma model for fluctuations of the observable, and show that this leads to K-distributions. We draw attention to the fact that these heavy-tailed distributions have high interest in physical applications, and we discuss them in some details.  相似文献   

6.
In this work, the use of an asymmetric feedback technique for improving the beam quality of a broad-area diode laser is investigated using numerical simulations. A mirror stripe is placed in the external cavity to select lateral mode and provide asymmetric feedback. The width and the position of the mirror stripe are optimized to improve the beam quality. The simulation results show a good beam quality of 0.7° FWHM and M 2 value of 2.69.  相似文献   

7.
A theoretical study of theβ +- andβ ?-decays of the74As nucleus is performed. Both non-relativistic and relativistic formfactor coefficients are calculated in the framework of the asymmetric rotor model with admixtures of two quasiparticles for transitional nuclei. The induced interactions are shown to have small contributions to the values of the formfactor coefficients in this case. The theoretical results for the principal observables are in good agreement with the experimental data in the case of the beta decays to the 2+ final states. The failure in describing the beta observables corresponding to the transitions to the ground states points to the existence of a more complex structure of the 0+-states in the daughter nuclei74Se and74Ge.  相似文献   

8.
The thermodynamic, elastic, elastic anisotropy and minimum thermal conductivity of β-GaN are investigated at ambient pressure and high temperature by using first-principles calculations method with the ultrasoft psedopotential scheme. The elastic constants calculations reveal β-GaN is mechanically stability at ambient pressure and high temperature. The elastic modulus (Poisson's ratio, shear modulus and Young's modulus) decreases with increasing temperature. The calculations of anisotropy show that β-GaN has a larger elastic anisotropy in Poisson's ratio, shear modulus, Young's modulus and Zener anisotropy index. In addition, when the temperature increases from 0 to 1500 K, the elastic anisotropy decreases for β-GaN. The quasi-harmonic Debye model is successfully applied to determine the thermodynamic properties at different pressures and temperatures. Using the quasi-harmonic Debye model, the thermodynamic properties including the Debye temperature, Grüneisen parameter, the heat capacity, adiabatic bulk modulus, and the thermal expansion coefficients of β-GaN are predicted under high temperature and high pressure.  相似文献   

9.
《Nuclear Physics A》2006,764(1-2):52-77
We discuss new physical phenomena expected in particle production in hadron–hadron collisions at high energy, as a consequence of pomeron loop effects in the evolution equations for the color glass condensate. We focus on gluon production in asymmetric, ‘dilute–dense’, collisions: a dilute projectile scatters off a dense hadronic target, whose gluon distribution is highly evolved. This situation is representative for particle production in proton–proton collisions at forward rapidities (say, at LHC) and admits a dipole factorization similar to that of deep inelastic scattering (DIS). We show that at sufficiently large forward rapidities, where the pomeron loop effects become important in the evolution of the target wavefunction, gluon production is dominated by ‘black spots’ (saturated gluon configurations) up to very large values of the transverse momentum, well above the average saturation momentum in the target. In this regime, the produced gluon spectrum exhibits diffusive scaling, so like DIS at sufficiently high energy.  相似文献   

10.
The various masses of fission products of U235-thermal fission were spacially separated by a helium filled magnetic mass separator. The number and energy of theβ-decays to the stable nuclides were counted and measured by a scintillation spectrometer. The time dependance of theβ-activity andβ-energy of the total of the U235 fission products was measured. The number ofβ-decays/fission was found to be (6,9±0,4)β-particles fission, the energy liberated byβ-decays (8,1±0,4) MeV/fission. A calculation of the totalβ-decay energy is given and compared with experimental data. The chainlengths ofβ-decay chains as a function of mass of the fission products were measured. Data on prompt neutron emission from fission products combined with the chainlength measurement give the mass dependance of the most probable charge of the primarily formed fission products. A recent model of asymmetric fission is shown to agree with the experimental data. The data give strong evidence that the filled nucleon shells ofZ=50 andN=50 are responsible for the asymmetric fission mechanism.  相似文献   

11.
The introduction of molybdenum nanoparticles in MoSe x thin films formed by pulsed laser deposition led to changes in the film structure. The base planes of the layered atomic packing of the MoSe х matrix around Mo nanoparticles rotated; as a consequence, the edge sites that formed during the “breaking” of the Se–Mo–Se layered atomic packing came out to the film surface. At high nanoparticle concentrations, this effect led to high density of edge sites possessing increased catalytic activity (compared with that of the base planes) for initiating the electrochemical evolution of hydrogen in a 0.5 M H2SO4 solution. Voltammetric measurements at room temperature showed that when the carbon cathode was coated with MoSe x thin films under optimum conditions, the hydrogen overvoltage considerably decreased, and the cathodic current increased. The results indicate that developments in the field of preparation of nanostructured electrodes based on layered transition metal dichalcogenides show promise as an alternative to expensive electrodes based on platinum group metals for electrocatalysts of hydrogen evolution.  相似文献   

12.
B. Roy Frieden 《Physica A》2010,389(2):287-2570
We present an expression of the economic concept of asymmetric information with which it is possible to derive the dynamical laws of an economy. To illustrate the utility of this approach we show how the assumption of optimal information flow leads to a general class of investment strategies including the well-known Q theory of Tobin. Novel consequences of this formalism include a natural definition of market efficiency and an uncertainty principle relating capital stock and investment flow.  相似文献   

13.
We studied the roughness evolution of Si surfaces upon Ar ion erosion in real time. Following the theory of surface kinetic roughening, a model proposed by Majaniemi was used to obtain the value of the dynamic scaling exponent β from our data. The model was found to explain both the observed roughening and the smoothening of the surfaces. The values of the scaling exponents α and β, important for establishing a universal model for ion erosion of (Si) surfaces, have been determined. The value of β proved to increase with decreasing ion energy, while the static scaling exponent α was found to be ion energy independent.  相似文献   

14.
Lingzao Zeng  Bohou Xu 《Physica A》2010,389(22):5128-5136
We study properties of parameter-induced aperiodic stochastic resonance in the presence of asymmetric Lévy noise. The system performance is characterized by the bit error rate. Investigations are based on the numerical solution of the space-fractional Fokker-Planck equation and Monte Carlo simulations. After choosing the optimal detection threshold, it is shown that the skewness parameter β has very limited influence on the system performance. Under the same conditions, the system performance is slightly reduced with the increasing β. The stability index α has the dominant effects on the system performance. The lower value of α leads to the better system performance.  相似文献   

15.
We have carried out a series of measurements of the resistivity of a high quality single crystal of Y-Ba-Cu-O, near the superconducting transition temperature, as a function of field varying to a maximum of 5 T applied in the a-b plane of the crystal. The results of the measurements are described accurately in terms of a model for phase-slip resistivity given by Tinkham which features phase-slip dissipation in small Josephson junctions. Since this is a crystal, the junctions are not present as a consequence of grain boundaries, but are believed to be a consequence of defects in oxygen (vacancy) ordering in the charge reservoir layers. As a result, the junctions are believed to be intrinsic to the material. The defects which give rise to the junctions are likely candidates for intrinsic pinning centers. This model is compared to a vortex-liquid state model discussed by Chien et al.  相似文献   

16.
The role of punishments in promoting cooperation is an important issue. We incorporate costly punishments into the snowdrift game (SG) by introducing a third punishing (P) character, and study the effects. The punishers, who carry basically a cooperative (C) character, are willing to pay a cost α so as to punish a non-cooperative (D) opponent by β. Depending on the initial fractions of the characters, α, β, and the cost-to-benefit ratio r in the SG, the three-character system evolves into a steady state consisting either only of C and P characters or only of C and D characters, in a well-mixed population. The former situation represents an enhancement in cooperation relative to the SG, while the latter is similar to the SG. The dynamics in approaching these different steady states are found to be different. Analytically, the key features in the dynamics and the steady states observed in simulations are captured by a set of differential equations. The sensitivity to the initial distribution of characters is studied by depicting the flow in a phase portrait and analyzing the nature of fixed points. The analysis also shows the role of P-character agents in preventing a system from invasion by D-character agents. Starting from a population consisting only of C and P agents, a D-character agent intended to invade the system cannot survive when the initial fraction of P agents is greater than r/β. Our model, defined intentionally as a simulation algorithm, can be readily generalized to incorporate many interesting effects, such as those in a networked population.  相似文献   

17.
18.
Within the framework of fractional calculus with variable order the evolution of space in the adiabatic limit is investigated. Based on the Caputo definition of a fractional derivative using the fractional quantum harmonic oscillator a model is presented, which describes space generation as a dynamic process, where the dimension d of space evolves smoothly with time in the range 0 ≤ d(t) ≤ 3, where the lower and upper boundaries of dimension are derived from first principles. It is demonstrated, that a minimum threshold for the space dimension is necessary to establish an interaction with external probe particles. A possible application in cosmology is suggested.  相似文献   

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