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11.
We employ an agent‐based model to show that memory and the absence of an a priori best strategy are sufficient for self‐segregation and clustering to emerge in a complex adaptive system with discrete agents that do not compete over a limited resource nor contend in a winner‐take‐all scenario. An agent starts from a corner of a two‐dimensional lattice and aims to reach a randomly selected site in the opposite side within the shortest possible time. The agent is isolated during the course of its journey and does not interact with other agents. Time‐bound obstacles appear at random lattice locations and the agent must decide whether to challenge or evade any obstacle blocking its path. The agent is capable of adapting a strategy in dealing with an obstacle. We analyze the dependence of strategy‐retention time with strategy for both memory‐based and memory‐less agents. We derive the equality spectrum to establish the environmental conditions that favor the existence of an a priori best strategy. We found that memory‐less agents do not polarize into two opposite strategy‐retention time distributions nor cluster toward a center distribution. © 2004 Wiley Periodicals, Inc. Complexity 9: 41–46, 2004 相似文献
12.
In this paper, we examine a variant of the uncapacitated lot-sizing model of Wagner–Whitin that includes fixed charges on the stocks. Such a model is natural in a production environment where stocking is a complex operation, and appears as a subproblem in more general network design problems.
Linear-programming formulations, a dynamic program, the convex hull of integer solutions and a separation algorithm are presented. All these turn out to be very natural extensions of the corresponding results of Barany et al. (Math. Programming Stud. 22 (1984) 32) for the uncapacitated lot-sizing problem. The convex hull proof is based on showing that an extended facility location formulation is tight and by projecting it onto the original space of variables. 相似文献
13.
The bias dependent interface charge is considered as the origin of the observed non-ideality in current–voltage and capacitance–voltage characteristics. Using the simplified model for the interface electronic structure based on defects interacting with the continuum of interface states, the microscopic origin of empirical parameters describing the bias dependent interface charge function is investigated. The results show that in non-ideal metal–semiconductor contacts the interface charge function depends on the interface disorder parameter, density of defects, barrier pinning parameter and the effective gap center. The theoretical predictions are tested against several sets of published experimental data on bias dependent ideality factor and excess capacitance in various metal–semicoductor systems. 相似文献
14.
The occurrence of charge on recoil56Mn produced by the (n,γ) reaction in polycrystalline potassium permanganate has been examined using the ‘charge plate technique’.
From considerations of capture gamma ray decay schemes and internal conversion it appears that, in a condensed medium, the
recoil atom develops charge after losing much of its initial kinetic energy which allows collection on charged electrodes.
Preliminary findings were presented at the International Symposium on Radiochemistry and Radiation Chemistry, RC-41 BARC,
Bombay, Feb. 4–6 (1991). 相似文献
15.
《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(27):7007-7007
16.
基于完全信息博弈理论,阐述了寡头垄断市场的排污收费古诺模型.建立了具有政府宏观调控机制的博弈模型,并对调控效果进行了分析. 相似文献
17.
Yu. Gangrsky 《Hyperfine Interactions》2006,171(1-3):203-208
This review summarizes the experimental data on charge radii differences among ground state and high spin isomeric states
determined by high-resolution laser spectroscopic methods. A comparison is presented between radii changes obtained from the
isomeric shifts in the atomic spectra and from the quadrupole moments of both ground and isomeric states under the assumption
that the radii changes are determined by the difference of the quadrupole deformations. Special attention is paid to isomers
arising from the break-up of nucleon pairs and isomers of odd–odd nuclei. The characteristic features of the radii changes
for isomeric states of different origin are discussed. 相似文献
18.
S. C. Tiwari 《Foundations of Physics Letters》2006,19(1):51-62
Advances in gauge theories and unified theories have not thrown light on the meaning of electron. The problem of the origin
of electronic charge is made precise, new insights gained from Weyl space are summarized, and the origin of charge in terms
of fractional spin is suggested. A new perspective on the abelian Chern-Simons theory is presented to explain charge. 相似文献
19.
Satya Prakash 《Pramana》1989,33(1):109-131
This article summarizes the recent radiochemical investigations on mass, charge kinetic energy and fragment angular distributions
in low energy fission of actinides. 相似文献
20.
Summary We report on neutron emission in palladium and titanium electrolitically charged with deuterium. The detection of neutrons
is observed after thermal treatment of the electrode. In the hypothesis that neutrons came from cold fusion processes, we
estimate a fusion rate as high as 1.3·10−21 fusions/deuteron pair/second. 相似文献