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论文/程序题目	作者	下载	主要内容介绍	Hits
Allometric Scaling of Countries	Jiang Zhang,Tongkui Yu		As huge complex systems consisting of geographic regions, natural resources, people and economic entities, countries follow the allometric scaling law which is ubiquitous in ecological, urban systems. We systematically investigated the allometric scaling relationships between a large number of macroscopic properties and geographic (area), demographic (population) and economic (GDP, gross domestic production) sizes of countries respectively. We found that most of the economic, trade, energy consumption, communication related properties have significant super-linear (the exponent is larger than 1) or nearly linear allometric scaling relations with GDP. Meanwhile, the geographic (arable area, natural resources, etc.), demographic(labor force, military age population, etc.) and transportation-related properties (road length, airports) have significant and sub-linear (the exponent is smaller than 1) allometric scaling relations with area. Several differences of power law relations with respect to population between countries and cities were pointed out. Firstly, population increases sub-linearly with area in countries. Secondly, GDP increases linearly in countries but not super-linearly as in cities. Finally, electricity or oil consumptions per capita increases with population faster than cities.	59
Scaling Behaviors of Weighted Food Webs as Energy Transportation Networks	Jiang Zhang,Liangpeng Guo		Food webs can be regarded as energy transporting networks in which the weight of each edge denotes the energy flux between two species. By investigating 21 empirical weighted food webs as energy flow networks, we found several ubiquitous scaling behaviors. Two random variables Ai and Ci defined for each vertex i, representing the total flux (also called vertex intensity) and total indirect effect or energy store of i, were found to follow power law distributions with the exponents \alpha=1.32 and \beta=1.33, respectively. Another scaling behavior is the power law relationship, Ci~Ai^{\eta}, where \eta=1.02. This is known as the allometric scaling power law relationship because Ai can be treated as metabolism and Ci as the body mass of the subnetwork rooted from the vertex i, according to the algorithm presented in this paper. Finally, a simple relationship among these power law exponents, \eta =(\alpha−1)/(\beta−1), was mathematically derived and tested by the empirical food webs.	135
Modeling Multi-species Interacting Ecosystem by a Simple Equation	Jiang Zhang		An ecosystem can be viewed as an energy flow system in which various species are connected by energy flows along food web links. To understand the co-evolution of the fast dynamics of energy flows and slow dynamics of food web structure, a simple reaction diffusion equation is presented in this paper. Some statistical indicators such as total system throughflow (TST) and Shannon entropy are designed to describe the macro-level evolution of the system. The positive correlation between time series of TST and Shannon entropy is mainly shown. That means the diversity of the species may accelerate the total energy flows in the system. This conclusion may help us to understand general phenomena of flows and diversity in other complex systems.	127
Energy Flows in Complex Ecological Systems: A Review	Jiang Zhang		Energy flow drives the complex systems to evolve. The allometric scaling as the universal energy flow pattern has been found in different scales of ecological systems. It reflects the general power law relationship between flow and store. The underlying mechanisms of energy flow patterns are explained as the branching transportation networks which can be regarded as the result of systematic optimization of a biological target under constraints. Energy flows in the ecological system may be modelled by the food web model and population dynamics on the network. This paper reviews the latest progress on the energy flow patterns, explanatory models for the allometric scaling and modelling approach of flow and network evolution dynamics in ecology. Furthermore, the possibility of generalizing these flow patterns, modelling approaches to other complex systems is discussed.	120
Complexity and Universality of Iterated Finite Automata	Jiang Zhang		Iterated Finite Automaton (IFA) is invented by Wolfram for studying the conventional Finite State Automata(FSA) by means of A New Kind of Science (NKS) methodology. An IFA is a composition of a finite state automaton and a tape with limited cells. The complexity of behaviors generated by various FSA operating on different tapes can be visualized by two dimensional patterns. Through enumerating all possible 2-state and 3-color IFA, this paper shows that there are a variety of complex behaviors in these simple computational systems. These patterns can be divided into 8 classes roughly such as regular patterns, noisy structures, complex behaviors, and so forth. Also they show the similarity between iterated finite automata and elementary cellular automata. Furthermore, any cellular automaton can be emulated by an IFA and vice versa. That means IFA supports universal computation.	120
Allometric Scaling of Weighted Food Webs	Jiang Zhang		Allometric scaling is an important universal property of metabolic living systems. It also describes the self-similar branching tree-liked structures in transportation networks. This paper presented a new approach to calculate the allometric scaling power law relations for arbitrary flow networks. This method can not only avoid the shortcoming of losing lots of information in the process of generating spanning trees in the conventional approaches but also can be applied to arbitrary weighted networks. The allometric scaling properties of 20 empirical weighted food webs (weights are energy fluxes) are computed according to the new approach, the power law relationships are derived with the universal exponent \eta = 1.0298 which reflects the transportation efficiency of the food webs.	81
Quantum computers	T. D. Ladd,F. Jelezko		Over the past several decades, quantum information science has emerged to seek answers to the question: can we gain some advantage by storing, transmitting and processing information encoded in systems that exhibit unique quantum properties? Today it is understood that the answer is yes, and many research groups around the world are working towards the highly ambitious technological goal of building a quantum computer, which would dramatically improve computational power for particular tasks. A number of physical systems, spanning much of modern physics, are being developed for quantum computation. However, it remains unclear which technology, if any, will ultimately prove successful. Here we describe the latest developments for each of the leading approaches and explain the major challenges for the future.	136
The role of models in science	Arturo Rosenblueth,Norbert Wiener		foundation papers in Complexity	147
studying artificial life with cellular automata	C.G. Langton		foundation papers in studying complexity	144
universality and complexity in cellular automata	Stephen Wolfram		foundation papers in studying complexity	196
复杂系统经典论文				262
A unified theory of biogeography and relative species abundance and its apllication of tropical rain forest and coral reefs	Stephen Hubbell		Theories of island biogeography and of relative species abundance are of central importance in biogeography and community ecology, yet these two bodies of theory heretofore have been largely unconnected. Incorporating speciation into the theory of island biogeography unexpectedly results in unification of these two theories. The unifed theory predicts the existence of a fundamental biodiversity number h that controls not only species richness, but also relative species abundance in the source area metacommunity at equilibrium between speciation and extinction. With additional parameters for island size and migration rate, the theory also predicts relative species abundance on islands or local regions of continuous landscapes. Application of the theory to the biogeography and biodiversity of communities of tropical trees and reefbuilding corals are discussed. One important result is that only relatively modest migration rates are suient to dynamically couple the regional metacommunity and stabilize community structure on large spatiotemporal scales. Thus, regional, long-term compositional stasis in tropical rain forests and coral reefs can arise just as easily from the stabilizing ect of large numbers as from nicheassembly rules that limit species membership in communities. Because of the higher intrinsic vagility of corals, the theory predicts greater regional similarity in coral reef communities than in tropical tree communities.	169
Global patterns of speciation and diversity	MAMde Aguiar,M.Baranger			203
A Novel Ensemble in Statistical Physics	I. Volkov,J.R. Banavar			213
Applications of the principle of maximum entropy: from physics to ecology	Jayanth R Banavar,Amos Maritan			216
Neutral theory and relative species	Igor Volkov,Jayanth R. Banavar			218
Godel, Escher, Bach --- An Enternal Golden Braid	Hofstadter		电子书：Godel, Escher, Bach --- An Enternal Golden Braid的英文版，这是一部旷世奇作	123
M.C.Escher’s Legacy——A Centennial Celebration	Doris Schattschneider,Michele Emmer		电子书：埃舍尔的遗产这是一个论文集，1998年在罗马召开的几年埃舍尔百年会议。其中涵盖哲学、艺术、科学等内容	88
生物多样性的中性理论与多样性格局	何芳良,胡新生			487
Power laws, Pareto distributions and Zipf’s law	M. E. J. Newman			309

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