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101.
We report computer simulation experiments based on our agent‐based simulation tool to model the multiperson Chicken dilemma game for the case when the agents are greedy simpletons who imitate the action of that of their neighbors who received the highest payoff for its previous action. The individual agents may cooperate with each other for the collective interest or may defect, i.e., pursue their selfish interests only. After a certain number of iterations the proportion of cooperators stabilizes to either a constant value or oscillates around such a value. The payoff (reward/penalty) functions are given as two straight lines: one for the cooperators and another for the defectors. The payoff curves are functions of the ratio of cooperators to the total number of agents. Even for linear payoff functions, we have four free parameters that determine the payoff functions that have the following properties: (1) Both payoff functions increase with the increasing number of cooperators. (2) In the region of low cooperation the cooperators have a higher reward than the defectors. (3) When the cooperation rate is high, there is a higher payoff for defecting behavior than for cooperating behavior. (4) As a consequence, the slope of the D function is greater than that of the C function and the two payoff functions intersect. (5) All agents receive a lower payoff if all defect than if all cooperate. We have investigated the behavior of the agents systematically. The results show that the solutions have predictable tendencies but they are nontrivial and quite irregular. The solutions show drastic changes in the parameter ranges 0.6 ≤ R ≤ 0.65 for all values of S and 0 ≤ S ≤ 0.2 when R < 0.6 (R is the reward for mutual cooperation and S is the sucker's payoff to a lonely cooperator). © 2010 Wiley Periodicals, Inc. Complexity, 2010 相似文献
102.
This paper presents theoretical investigation of the propagation of surface acoustic waves (SAWs) across the boundary between metallized (electrically shorted) and unmetallized (electrically open) regions on the surface of potassium niobate crystals. Potassium niobate is a very strong piezoelectric material and has the interesting property that only one type of SAW, namely a Rayleigh wave, can exist on unmetallized surface, where as two types of SAWs, namely Rayleigh and Bleustein-Gulyaev (BG), can exist on a metallized surface. Analysis shows that the Rayleigh wave propagates through the interface with very little change in amplitude or polarization. On the other hand, almost total reflection of the BG wave is expected. Details of the theoretical analysis and calculated results will be presented. 相似文献
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R. Germann A. Forchel G. Weimann 《Applied Physics A: Materials Science & Processing》1988,47(4):373-376
Beveled cross-sections of semiconductors with inclination angles down to 0.25 min of arc have been produced with a special
ion beam etching process. We applied this technique to the depth resolved characterization of GaAs/GaAlAs multiple quantum
well structures by photoluminescence spectroscopy. The depth dependent incorporation of impurities during the growth of the
first quantum well layers is clearly revealed. 相似文献
107.
Single-interface modulation-doped AlGaAs-GaAs heterostructures have very high mobilities if thick undoped spacers are introduced between the Si donors and the twodimensional electron gas. Electron densities are limited to values below 1012 cm–2. Higher channel densities are desirable for device applications and can be obtained by confining the electrons in quantum wells doped from both sides. Single quantum-well structures have been grown with sheet carrier densities exceeding 3×1012 cm–2 at 300 K and 77 K mobilities of 54,000 cm2/Vs. Single quantum wells doped from one side only with low electron concentrations of 2×1011 cm–2 have 4.2 K mobilities of 200,000cm2/Vs. 相似文献
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