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51.
This paper proposes a new model of Incomplete Minority Game (IMG), which features a default hierarchy of rules. This model introduces random bits into players’ individual strategies and is capable of applying the exception rules in the absence of the default one. Analysis of the numerical experiment results indicates that, in comparison with the standard Minority Game (SMG) model, this IMG model expands the maximum ensemble of uncorrelated strategies (MEUS) and excels in the effective strategy set and dynamic evolution of individual strategies, which enhance the overall performance by reaching an approximate ideal status in a shorter time with less memory steps and more stable combination of strategies. This paper also discusses the practical implication of the new IMG model. 相似文献
52.
The perovskite-type ceramic La0.7Ca0.3MnO3−δ was prepared by the solid-state reaction with 0.00?δ?0.15. X-ray diffraction, electrical and magnetic measurements were performed to examine the effect of the B-site size on the properties of these materials. We have found that the structure is orthorhombic for 0.00?δ?0.075 and becomes rhombohedral for 0.10?δ?0.15. The measurements of the magnetization as a function of the temperature, M(T), shows a ferromagnetic-paramagnetic transition at the Curie temperature TC for δ=0.00. When increasing δ, these curves report the presence of two types of transitions. The first one is from the ferromagnetic to the antiferromagnetic state, indicating the existence of a charge-ordering state (TCO). The second antiferromagnetic-paramagnetic transition occurs at the Neel temperature TN. The temperature dependence of the resistivity ρ(T), indicates a metallic behaviour at low temperature (T<Tp) and a semiconductor behaviour at high temperature (T>Tp) for δ=0.00. For 0.05?δ?0.10, the ρ(T) curves shows a semiconductor behaviour revealing the disappearance of the metallic state which reappear at low temperature for δ=0.125 and 0.150. 相似文献
53.
Magnetic nanocomposites can be controlled and tailored to provide the desired mechanical, physical, chemical, and biomedical properties depending on the final applications. The coating of ferrite nanoparticles with polymers affords the possibility of minimizing agglomeration in large-scale commercial synthesis of nanocomposite materials. The process of coating not only provides effective encapsulation of individual nanoparticles, but also controls the growth in size, thus, yielding a better overall size distribution. In this paper, in-situ polymerization of aniline was carried out in different concentration of the ferrofluid with the aim to obtain agglomerate free nanocomposites. The role of the ferrite concentration was investigated by the spectral, morphological, conductivity, and magnetic properties of Fe3O4/polyaniline (PANI) nanocomposites. XRD revealed the presence of spinel phase of Fe3O4 and the particle size was calculated to be 14.3 nm. Spectral analysis confirmed the formation of PANI encapsulated Fe3O4 nanocomposite. Conductivity of the nanocomposites was found to be in the range of 0.001–0.003 S/cm. Higher saturation magnetization of 3.2 emu/g was observed at 300 K, revealing a super paramagnetic behavior of this nanocomposite. 相似文献
54.
A novel super-FEC code based on concatenated code for high-speed long-haul optical communication systems 总被引:3,自引:0,他引:3
The structures of the novel super forward error correction (Super-FEC) code type based on the concatenated code for high-speed long-haul optical communication systems are studied in this paper. The Reed-Solomon (RS) (255, 239) + Bose-Chaudhuri-Hocguenghem (BCH) (1023, 963) concatenated code is presented after the characteristics of the concatenated code and the two Super-FEC code type presented in ITU-T G.975.1 have theoretically been analyzed, the simulation result shows that this novel code type, compared with the RS (255, 239) + convolutional-self-orthogonal-code (CSOC) (k0/n0 = 6/7, J = 8) code in ITU-T G.975.1, has a lower redundancy and better error-correction capabilities, and its net coding gain (NCG) at the third iteration is 0.57 dB more than that of RS (255, 239) + CSOC (k0/n0 = 6/7, J = 8) code in ITU-T G.975.1 at the third iteration for the bit error rate (BER) of 10−12. Therefore, the novel code type can better be used in long-haul, larger capacity and higher bit-rate optical communication systems. Furthermore, the design and implementation of the novel concatenated code type are also discussed. 相似文献
55.
该文研究局部凸空间中受集值约束的集值优化问题的超有效解. 证明了ic -锥-类凸集值映射的一个有用性质, 并以此性质为主要工具, 得到了ic -锥-类凸集值向量优化问题超有效解的最优性条件和鞍点定理. 相似文献
56.
The additional symmetries of the constrained CKP (cCKP) and BKP (cBKP) hierarchies are given by their actions on the Lax operators, and their actions on the eigenfunction and adjoint eigenfunction {Φ i , Ψ i } are presented explicitly. Furthermore, we show that acting on the space of the wave operator, *k forms new centerless W cC 1+∞ and W cB 1+∞ -subalgebra of centerless W 1+∞ respectively. In order to define above symmetry flows *k of the cCKP and cBKP hierarchies, two vital operators Y k are introduce... 相似文献
57.
We study some variations of the so‐called Hardy hierarchy (up to ε0) of quickly growing functions, known from the literature, and obtain analogues of Ratajczyk's approximation lemma for them. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
58.
59.
积因子求权重层次分析法在城市排序中的应用 总被引:2,自引:0,他引:2
克服传统层次分析法确定因素权重主观性太强的不足,结合积因子方法给出了积因子赋值求权重层次分析法,并利用该方法对黑龙江省各城市按可持续发展指标进行排序,得到符合实际的结果. 相似文献
60.
Franz Wirl 《Computational Management Science》2008,5(4):393-401
This note shows that the second derivative of the value function exists (across a stopping threshold, short “super contact”)
if reversibly stopping and entering involves no cost, called “switching”. This holds for discrete (real option) as well as
for continuous stochastic control problems and proves particularly suitable in real option set ups since it provides the lacking
boundary condition. However, super contact does not hold in dynamic games. A simple example documents the applicability of
this condition.
This paper was written during my visit of the University of Technology, Sydney (UTS) and I am grateful for the hospitality
of and the stimulus at the School of Finance and Economics, in particular to Carl Chiarella. I also acknowledge many helpful
discussions with Thomas Dangl on related issues, valuable suggestions from a referee and last but not least encouragement
by Josef Kallrath 相似文献