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In order to understand the interplay among information, genetic instructions, and phenotypic variations, self‐reproducers discovered in two‐dimensional cellular automata are considered as proto‐organisms, which undergo to mutations as they were in a real environmental situation. We realized a computational model through which we have been able to discover the genetic map of the self‐reproducers and the networks they use. Identifying in these maps sets of different functional genes, we found that mutations in the genetic sequences could affect both external shapes and behavior of the self‐reproducers, thus realizing different life‐like strategies in the evolution process. The results highlight that some strategies evolution uses in selecting organisms that are fitting with changing environmental situations maintain the self‐reproducing function, whereas other variations create new self‐reproducers. These self‐reproducers in turn realize different genetic networks, which can be very different from the basic ancestors pools. The mutations that are disruptive bring self‐reproducers to disappear, while other proto‐organisms are generated. © 2004 Wiley Periodicals, Inc. Complexity 9: 38–55, 2004 相似文献
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基于自组织理论的GMDH神经网络算法及应用 总被引：12，自引：0，他引：12
本文在自组织控制论的基础上提出了成组数据处理的神经网络算法— GMDH算法 ,通过寻找最优复杂性 ,实现变量的自动筛选并得到明确的模型结构 .文章还给出了 GMDH网络用于分析和预测四川省电力需求状况的一个实例 相似文献
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Huddling is a grouping behavior where animals maintain close bodily contact and save energy. We tested the hypothesis that this thermoregulatory behavior behaves as a system with continuous (second‐order phase) transition called critical when the environmental temperature (driving parameter) is near a critical value. To do so, we followed theoretical and experimental approaches, examining data from geometrical models, metabolic rate during huddling in small mammals, and also conducting an experiment on thermoregulatory huddling behavior with white mice. Our results support all predictions for systems under continuous‐phase transition triggered by low temperatures, a phenomenon reported for first time in a biological system. We suggest that huddling behavior in social animals, a recognized adaptive behavior, may be considered a self‐organized system coupled with an external driving parameter. © 2011 Wiley Periodicals, Inc. Complexity, 2011 相似文献
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David Défossez 《Journal of Graph Theory》2009,62(2):139-156
In this paper we investigate the problem of clique‐coloring, which consists in coloring the vertices of a graph in such a way that no monochromatic maximal clique appears, and we focus on odd‐hole‐free graphs. On the one hand we do not know any odd‐hole‐free graph that is not 3‐clique‐colorable, but on the other hand it is NP‐hard to decide if they are 2‐clique‐colorable, and we do not know if there exists any bound k0 such that they are all k0 ‐clique‐colorable. First we will prove that (odd hole, codiamond)‐free graphs are 2‐clique‐colorable. Then we will demonstrate that the complexity of 2‐clique‐coloring odd‐hole‐free graphs is actually Σ2 P‐complete. Finally we will study the complexity of deciding whether or not a graph and all its subgraphs are 2‐clique‐colorable. © 2009 Wiley Periodicals, Inc. J Graph Theory 62: 139–156, 2009 相似文献
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The idea of emergence originates from the fact that global effects emerge from local interactions producing a collective coherent behavior. A particular instance of emergence is illustrated by a flocking model of interacting “boids” encompassing two antagonistic conducts—consensus and frustration—giving rise to highly complex, unpredictable, coherent behavior. The cohesive motion arising from consensus can be described in terms of three ordered dynamic phases. Once frustration is included in the model, local phases for specific groups of flockmates, and transitions among them, replace the global ordered phases. Following the evolution of boids in a single group, we discovered that the boids in this group will alternate among the three phases. When we compare two uncorrelated groups, the second group shows a similar behavior to the first one, but with a different sequence of phases. Besides the visual observation of our animations with marked boids, the result is evident plotting the local order parameters. Rather than adopting one of the consensus ordered phases, the flock motion resembles more an entangled dynamic sequence of phase transitions involving each group of flockmates. © 2015 Wiley Periodicals, Inc. Complexity 21: 69–78, 2016 相似文献
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通过分析几种估计增长网络度分布方法的缺点,提出估计度分布的差分方程方法,不仅避免了复杂网络分析中将离散问题连续化带来的逻辑矛盾,也避免了网络稳态度分布存在性的假设．利用这个方法给出Poisson增长择优连接网络的度分布公式,借助Poisson过程理论和Gamma分布的性质严格证明Poisson增长择优连接网络是无标度网络． 相似文献
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Franciszek Grabowski 《Complexity》2013,18(5):28-36
The article concerns the new nonextensive model of self‐organizing systems and consists of two interrelated parts. The first one presents a new nonextensive model of interaction between elements of systems. The second one concerns the relationship between microscopic and macroscopic processes in complex systems. It is shown that nonextensivity and self‐organization of systems is a result of mismatch between its elements. © 2013 Wiley Periodicals, Inc. Complexity 18: 28–36, 2013 相似文献
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For many systems characterized as “complex” the patterns exhibited on different scales differ markedly from one another. For example, the biomass distribution in a human body “looks very different” depending on the scale at which one examines it. Conversely, the patterns at different scales in “simple” systems (e.g., gases, mountains, crystals) vary little from one scale to another. Accordingly, the degrees of self‐dissimilarity between the patterns of a system at various scales constitute a complexity “signature” of that system. Here we present a novel quantification of self‐dissimilarity. This signature can, if desired, incorporate a novel information‐theoretic measure of the distance between probability distributions that we derive here. Whatever distance measure is chosen, our quantification of self‐dissimilarity can be measured for many kinds of real‐world data. This allows comparisons of the complexity signatures of wholly different kinds of systems (e.g., systems involving information density in a digital computer vs. species densities in a rain forest vs. capital density in an economy, etc.). Moreover, in contrast to many other suggested complexity measures, evaluating the self‐dissimilarity of a system does not require one to already have a model of the system. These facts may allow self‐dissimilarity signatures to be used as the underlying observational variables of an eventual overarching theory relating all complex systems. To illustrate self‐dissimilarity, we present several numerical experiments. In particular, we show that the underlying structure of the logistic map is picked out by the self‐dissimilarity signature of time series produced by that map. © 2007 Wiley Periodicals, Inc. Complexity 12: 77–85, 2007 相似文献
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Andreas Krause 《Complexity》2004,9(4):24-30
We consider an evolving network of interacting species which exhibits self‐organization. The system is characterized by repeated crashes in which a large number of species are extinct and subsequent recoveries. We investigate the macroscopic properties of this system before such crashes, concentrating on the variance of the relative population sizes of species and its evolution over time. A simple score function is constructed to determine the probability of a crash within a certain time interval to be used as a predictor for crashes. © 2004 Wiley Periodicals, Inc. Complexity 9: 24–30, 2004 相似文献
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熵是度量复杂系统无序性的重要物理量,而且现实中的大多数网络都呈现出无标度网络的特性.在网络的节点熵和结构熵概念的基础上,给出了BA模型的网络结构熵演化的解析结论和数值模拟.从解析结论和数值模拟可以得到,网络结构熵随网络大小以对数的速度增长;但在同样规模下,无标度网络的结构熵小于随机网络的结构熵. 相似文献
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Jesus Felix Valenzuela Christopher Monterola Erika Fille Legara Xiuju Fu Rick Siow Mong Goh 《Complexity》2015,21(1):283-295
We examine the transmission of entities from the peripheries of scale‐free networks toward their centers when the nodes of the network have finite processing capabilities. We look at varying network utilization, U and find that clogging of the network sets in after a threshold value has been exceeded, and that the congestion sets in at the downstream nodes (those nearer to the collector) having large numbers of upstream neighbors. Investigation of the question of the degree of correlation of several characteristics of scale‐free networks (such as the average path length to the collector <l(min)> and the average clustering coefficient ) with the dynamics of centripetal flow in them reveals a negative answer: any correlation is indirect and will manifest in the number of producer nodes (which dictate the effective heaviness of the flow) and the interconnectedness of the feeder nodes, those nodes which are immediate neighbors of the collector node. An examination of reinforcement strategies shows dramatic improvements in both the finishing rate, and the average total transmission time, when the more centrally‐placed nodes are reinforced first, showing that the entities spend a large amount of their lifetime waiting in line at those nodes (which constitute the bottlenecks in the network) compared to the nodes in the periphery. Our results reinforce the importance of a network's hubs and their immediate environs, and suggest strategies for prioritizing elements of a network for optimization. © 2014 Wiley Periodicals, Inc. Complexity 21: 283–295, 2015 相似文献
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Objective: The study aimed to analyze sexual networks and sex role preference as factors of HIV transmission among men who have sex with men (MSM) in China. Methods: We have developed a new scale‐free network model with a sex role preference framework to study HIV transmission among MSM. We have studied the influence of different sexual networks and the effect of different proportion of sex role preference upon HIV transmission. The results are that the average ones drawn from the scenarios have been simulated for more than 30 times. Results: Compared with the traditional mathematical model, the sexual networks provide a different prediction of the HIV transmission in the next 30 years. Without any intervention, the proportion of HIV carriers will descend after some time. Conclusions: There is significant associations among network characteristics, sex role preference, and HIV infection. Although network‐based intervention is efficient in reducing HIV transmission among MSM, there are only few studies of the characteristics of sexual network, and such gaps deserve more attention and exploration. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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从宏观的角度，组织具有有机生命物的特征，不但能够对外界环境的变化和刺激能够作出反应。而且还能意识到环境的变化并预先作出某种安排。即，体现出某种智能特性。在激烈的竞争和复杂多变的环境中组织如何能够生存下来并取得发展的问题，一直得到管理科学学的密切关注，也是研究的热点之一。按照复杂科学和当代管理科学的理论，并结合心理科学领域中的一般智能理论，本讨论了组织智能的一些理论基础，初步探讨了组织智能与组织生存的关系。 相似文献
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We compared entropy for texts written in natural languages (English, Spanish) and artificial languages (computer software) based on a simple expression for the entropy as a function of message length and specific word diversity. Code text written in artificial languages showed higher entropy than text of similar length expressed in natural languages. Spanish texts exhibit more symbolic diversity than English ones. Results showed that algorithms based on complexity measures differentiate artificial from natural languages, and that text analysis based on complexity measures allows the unveiling of important aspects of their nature. We propose specific expressions to examine entropy related aspects of tests and estimate the values of entropy, emergence, self‐organization, and complexity based on specific diversity and message length. © 2014 Wiley Periodicals, Inc. Complexity 20: 25–48, 2015 相似文献
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Sergio Pissanetzky 《Complexity》2011,17(2):19-38
The discovery of a simple functional the optimization of which by a dynamical process results in extraordinary structural organization in partially ordered sets is reported in this article. As partially ordered sets are one of the most prevalent and fundamental objects in Mathematics and are ubiquitous in nature, physics, engineering and technology in general, and since any system amenable to mathematical analysis can be represented as a partially ordered set, the discovery is proposed as an explanation for the phenomena of emergence and self‐organization in dynamical systems. © 2011Wiley Periodicals, Inc. Complexity, 17,19–38, 2011 相似文献
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The self‐similar tree topology in open dissipative systems is formed as a result of self‐organization and found in various examples, such as river networks, blood vessels, vascular organizations in plants, and even lightning. It is generally assumed that the tree organization is a result of a dynamic process that minimizes the dissipation of energy. Here, we argue that inherent randomness is a sufficient condition for the generation of tree patterns under evolutionary dynamics and the decrease of energy expenditure is not the cause but a consequent signature. © 2008 Wiley Periodicals, Inc. Complexity, 13: 30–37, 2008 相似文献
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Transition from local complexity to global spatio‐temporal dynamics in a two‐dimensional array of fluid‐elastic oscillators is examined experimentally with an apparatus comprising 90‐1000 cantilevered rods in a wind tunnel as the Reynolds number (based on rod diameter) is increased from 200 to 900. A cluster‐pattern entropy measure is introduced as a quantitative measure of local complexity. As the intensity of interaction among neighboring elements (in this case, frequency of collisions among rods) increases, a set of the elements (in this case, a rod‐array) achieves globally better‐organized behavior. On the basis of accelerometer data, the rod impact rate versus flow velocity shows a power‐law scaling relation. Video images reveal that, initially, each rod moves individually; then clusters consisting of several rods emerge. Finally, global wave‐like motion occurs at higher flow velocities. Each wave‐like motion has its specific frequency and spatial wavelength, which vary according to wind velocity. © 2007 Wiley Periodicals, Inc. Complexity 12: 36–47, 2007 相似文献
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Human language may have started from a consistent set of mappings between meanings and signals. These mappings, referred to as the early vocabulary, are considered to be the results of conventions established among the agents of a population. In this study, we report simulation models for investigating how such conventions can be reached. We propose that convention is essentially the product of self‐organization of the population through interactions among the agents and that cultural selection is another mechanism that speeds up the establishment of convention. Whereas earlier studies emphasize either one or the other of these two mechanisms, our focus is to integrate them into one hybrid model. The combination of these two complementary mechanisms, i.e., self‐organization and cultural selection, provides a plausible explanation for cultural evolution, which progresses with high transmission rate. Furthermore, we observe that as the vocabulary tends to convergence there is a uniform tendency to exhibit a sharp phase transition. © 2002 Wiley Periodicals, Inc. 相似文献
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A major obstacle in real‐time performance of a visual tracking system is its initialization phase. Inspired by social behavior in fish and ant groups, a fast self‐organization approach to active‐contour initialization is proposed. Contours are emerged during two separate phases of aggregation and self‐assembly. Aggregation is achieved by a superposition of simpler behaviors, hunting, avoidance, and opportunism. Self‐assembly, which constitutes the explicit contour formation, occurs by mating behavior when the swarm becomes quite stable. Experiments indicate that the proposed method outperforms exhaustive image search for finding contours in high resolutions. © 2006 Wiley Periodicals, Inc. Complexity 12: 41–52, 2006 相似文献