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101.
This study aims at figuring out the crucial topological ingredients which affect the outcomes of the ultimatum game located on different networks,encompassing the regular network,the random network,the small world network,and the scale-free network.With the aid of random interchanging algorithm,we investigate the relations between the outcomes of the ultimatum game and some topological ingredients,including the average range,the clustering coefficient and the heterogeneity,and so forth.It is found that for the regular,random and small-work networks,the average range and the clustering coefficient have evident impacts on the ultimatum game,while for the scale-free network the original degree heterogeneity and the underlying rich-club characterizations are the mainly important topologica ingredients that influence the outcomes of ultimatum game substantially. 相似文献
102.
103.
利用拉曼光谱方法,对柠檬酸钠辅助水热合成纳米结构多孔ZnO微球的机理进行了研究。样品的拉曼光谱特征显示,多孔ZnO微球中存在Zn-柠檬酸配合物;分析表明反应溶液中柠檬酸钠水解产生的柠檬酸根与Zn2+结合形成Zn-柠檬酸配合物,该配合物化学吸附在Zn(OH)2晶核的(204)和(503)晶面,使Zn(OH)2晶核择优生长形成纳米薄片状结构;水热过程中Zn(OH)2微晶团聚形成纳米片状结构多孔Zn(OH)2微球并以沉淀析出。研究发现吸附在薄片表面的Zn-柠檬酸配合物提高了Zn(OH)2微晶的热稳定性,使得Zn(OH)2的分解温度高于200 ℃,加热到300 ℃后Zn(OH)2完全分解获得纳米结构多孔ZnO微球。 相似文献
104.
文章扼要地评述了金融物理学研究进展,介绍了文章作者在金融动力学时空关联方面的最新研究成果,特别关注中西方金融市场的对比研究.唯象理论研究表明,西方金融市场的价格收益率和波动率的时间关联显示杠杆效应,而中国金融市场则显示反杠杆效应;一种价格收益率和波动率的反馈相互作用可以解释杠杆和反杠杆效应的起源.西方金融市场的个体股票价格的交叉关联呈现标准的行业板块结构,而中国金融市场展示的是一种特殊的板块结构,如"ST板块"和"蓝筹板块"等.股票价格大波动可分为动力学内部产生的和外部事件诱导的两大类.金融动力学的时间反演不对称性,主要来源于外部事件诱导的大波动. 相似文献
105.
The extended Riccati mapping approach^[1] is further improved by generalized Riccati equation, and combine it with variable separation method, abundant new exact complex solutions for the (2+1)-dimensional modified dispersive water-wave (MDWW) system are obtained. Based on a derived periodic solitary wave solution and a rational solution, we study a type of phenomenon of complex wave. 相似文献
106.
Sergey P. Gromov Svetlana N. Dmitrieva Artem I. Vedernikov Nikolay A. Kurchavov Lyudmila G. Kuz'mina Yuri A. Strelenko Michael V. Alfimov Judith A. K. Howard 《Journal of Physical Organic Chemistry》2009,22(9):823-833
An improved method for the synthesis of formyl derivatives of N‐methylbenzoazacrown ethers is proposed. They are prepared in up to 68% yields over fewer steps and with a much shorter time required for the last step. The stability constants of complexes formed by N‐methylbenzoazacrown ethers and their structural analogs with alkali metal, alkaline‐earth metal and ammonium cations were determined by 1H NMR titration in CD3CN. High stability of complexes of N‐methyl derivatives of benzoazacrown ethers is demonstrated, comparable with or even exceeding the stability of benzocrown‐ether complexes and markedly exceeding the stability of complexes of phenylazacrown ethers with the same macrocycle size. The structures of azacrown ethers and their complexes with Ba(ClO4)2 were studied by X‐ray diffraction. A high degree of pre‐organization of N‐methylbenzoazacrown ethers toward the formation of complexes with metal and ammonium cations was noted, which is due to the clear‐cut pyramidal geometry of the nitrogen atom and the orientation of the lone electron pairs (LEPs) of most heteroatoms towards the centre of the macroheterocycle. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
107.
In this paper, a fast method is proposed to estimate the sonar cross section of acoustically large and complex underwater targets such as submarines and torpedoes. The proposed method is based on a deterministic scattering center model which constructs scattering center database by using a combining method of physical optics and geometric optics and then reconstructs sonar cross section patterns from that database with a polynomial interpolation with respect to the incident angle. The parametric studies to find appropriate intervals of the reference incident angle are systematically carried out for simple targets such as a flat square plate and an orthogonal dihedral. Moreover, to validate the proposed method, sonar cross sections of real-like targets such as a pressure hull and an idealized submarine are calculated. The comparisons show that the results by the proposed method are in good agreement with those by the direct calculation. 相似文献
108.
The oil industry is now increasingly concentrating their efforts and activities in connection with developing fields in deeper
waters, ranging typically from 500 m to 3000 m worldwide. However, the modeling of a full-depth system has become difficult
presently; no tank facility is sufficiently large to perform the testing of a complete FPS with compliant mooring in 1000
m to 3000 m depth, within reasonable limits of model scale. Until recently, the most feasible procedure to meet this challenge
seems to be the so-called “hybrid model testing technique”. To implement this technique, the first and important step is to
design the equivalent water depth truncated mooring system. In this work, the optimization design of the equivalent water
depth truncated mooring system in hybrid model testing for deep sea platforms is investigated. During the research, the similarity
of static characteristics between the truncated and full depth system is mainly considered. The optimization mathematical
model for the equivalent water depth truncated system design is set up by using the similarity in numerical value of the static
characteristics between the truncated system and the full depth one as the objective function. The dynamic characteristic
difference between the truncated and full depth mooring system can be minished by selecting proper design rule. To calculate
the static characteristics of the mooring system, the fourth order Runge-Kutta method is used to solve the static equilibrium
equation of the single mooring line. After the static characteristic of the single mooring line is calculated, the static
characteristic of the whole mooring system is calculated with Lagrange numerical interpolation method. The mooring line material
database is established and the standard material name and the diameter of the mooring line are selected as the primary key.
The improved simulated annealing algorithm for continual & discrete variables and the improved complex algorithm for discrete
variables are employed to perform the optimization calculation. The C++ programming language is used to develop the computer
program according to the object-oriented programming idea. To perform the optimization calculation with the two algorithms
mentioned above respectively and the better result is selected as the final one. To examine the developed program, an example
of equivalent water depth truncated mooring system optimum design calculation on a 100,000-t, turret mooring FPSO in water
depth of 320 m are performed to obtain the conformation parameters of the truncated mooring system, in which the truncated
water depth is 160 m. The model test under some typical environment conditions are performed for both the truncated and the
full depth system with model scale factor λ=80. After comparing the corresponding results from the test of the truncated system with those from the full depth system
test, it’s found that the truncated mooring system design in this work is successful.
Supported by the National Natural Science Foundation of China (Grant Nos. 10602055 and 40776007) and the Natural Science Foundation
of China Jiliang University (Grant No. XZ0501) 相似文献
109.
D. Helbing 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,69(4):569-570
This contribution compares several different approaches allowing one to derive macroscopic traffic equation directly from
microscopic car-following models. While it is shown that some conventional approaches lead to theoretical problems, it is
proposed to use an approach reminding of smoothed particle hydrodynamics to avoid gradient expansions. The derivation circumvents
approximations and, therefore, demonstrates the large range of validity of macroscopic traffic equations, without the need
of averaging over many vehicles. It also gives an expression for the “traffic pressure”, which generalizes previously used
formulas. Furthermore, the method avoids theoretical inconsistencies of macroscopic traffic models, which have been criticized
in the past by Daganzo and others. 相似文献
110.
Y. Huang L. Wu S. Q. Zhu 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,69(3):431-438
The interaction between the evolution of the game and the underlying network structure with evolving snowdrift game model
is investigated. The constructed network follows a power-law degree distribution typically showing scale-free feature. The
topological features of average path length, clustering coefficient, degree-degree correlations and the dynamical feature
of synchronizability are studied. The synchronizability of the constructed networks changes by the interaction. It will converge
to a certain value when sufficient new nodes are added. It is found
that initial payoffs of nodes greatly affect the synchronizability. When initial payoffs for players are equal, low common
initial payoffs may lead to more heterogeneity of the network and good
synchronizability. When initial payoffs follow certain distributions, better synchronizability is obtained compared to equal
initial payoff. The result is also true for phase synchronization of nonidentical oscillators. 相似文献