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Network Dynamics
Network dynamics is a research field for the study of networks whose status changes in time. The dynamics may refer to the structure of connections of the units of a network, to the collective internal state of the network, or both. The networked systems could be from the fields of biology, chemistry, physics, sociology, economics, computer science, etc. Networked systems are typically characterized as complex systems consisting of many units coupled by specific, potentially changing, interaction topologies. For a dynamical systems In mathematics, a dynamical system is a system in which a Function (mathematics), function describes the time dependence of a Point (geometry), point in an ambient space, such as in a parametric curve. Examples include the mathematical models ...' approach to discrete network dynamics, see sequential dynamical system. See also References Networks {{combin-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Theory
In mathematics, computer science, and network science, network theory is a part of graph theory. It defines networks as Graph (discrete mathematics), graphs where the vertices or edges possess attributes. Network theory analyses these networks over the symmetric relations or directed graph, asymmetric relations between their (discrete) components. Network theory has applications in many disciplines, including statistical physics, particle physics, computer science, electrical engineering, biology, archaeology, linguistics, economics, finance, operations research, climatology, ecology, public health, sociology, psychology, and neuroscience. Applications of network theory include Logistics, logistical networks, the World Wide Web, Internet, gene regulatory networks, metabolic networks, social networks, epistemological networks, etc.; see List of network theory topics for more examples. Euler's solution of the Seven Bridges of Königsberg, Seven Bridges of Königsberg problem is c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynamic Network Analysis
Dynamic network analysis (DNA) is an emergent scientific field that brings together traditional social network analysis (SNA), link analysis (LA), social simulation and multi-agent systems (MAS) within network science and network theory. Dynamic networks are a function of time (modeled as a subset of the real numbers) to a set of graphs; for each time point there is a graph. This is akin to the definition of dynamical systems, in which the function is from time to an ambient space, where instead of ambient space time is translated to relationships between pairs of vertices. Overview There are two aspects of this field. The first is the statistical analysis of DNA data. The second is the utilization of simulation to address issues of network dynamics. DNA networks vary from traditional social networks in that they are larger, dynamic, multi-mode, multi-plex networks, and may contain varying levels of uncertainty. The main difference of DNA to SNA is that DNA takes interactio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baruch Barzel
Baruch Barzel (; March 19, 1976) is an Israeli physicist and applied mathematician at Bar-Ilan University, a member of the Gonda Multidisciplinary Brain Research Center and of the Bar-Ilan Data Science Institute. His main research areas are statistical physics, complex systems, nonlinear dynamics and network science. In 2013 he introduced the concept of universality in the dynamics of complex networks, showing that complex systems from different domains condense into discrete forms, or universality classes, of dynamic behavior. In the following years, Barzel and colleagues developed a theoretical framework to predict the observed behavior of complex networked systems: their patterns of information flow; the timescales of their signal propagation; their resilience against failures and disruptions and their recoverability. During the COVID-19 PandemiBarzel's lab published the alternating quarantine strategy to mitigate the spread of SARS-CoV-2 alongside continuous socioeconomic a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technology Dynamics
Technology dynamics is broad and relatively new scientific field that has been developed in the framework of the postwar science and technology studies field. It studies the process of technological change. Under the field of Technology Dynamics the process of technological change is explained by taking into account influences from "internal factors" as well as from "external factors". Internal factors relate technological change to unsolved technical problems and the established modes of solving technological problems and external factors relate it to various (changing) characteristics of the social environment, in which a particular technology is embedded. Overview For the last three decades, it has been argued that technology development is neither an autonomous process, determined by the "inherent progress" of human history, nor a process completely determined by external conditions like the prices of the resources that are needed to operate (develop) a technology, as it is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small-world Network
A small-world network is a graph characterized by a high clustering coefficient and low distances. In an example of the social network, high clustering implies the high probability that two friends of one person are friends themselves. The low distances, on the other hand, mean that there is a short chain of social connections between any two people (this effect is known as six degrees of separation). Specifically, a small-world network is defined to be a network where the typical distance ''L'' between two randomly chosen nodes (the number of steps required) grows proportionally to the logarithm of the number of nodes ''N'' in the network, that is: :L \propto \log N while the global clustering coefficient is not small. In the context of a social network, this results in the small world phenomenon of strangers being linked by a short chain of acquaintances. Many empirical graphs show the small-world effect, including social networks, wikis such as Wikipedia, gene n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurodynamics
Neural oscillations, or brainwaves, are rhythmic or repetitive patterns of neural activity in the central nervous system. Neural tissue can generate oscillatory activity in many ways, driven either by mechanisms within individual neurons or by interactions between neurons. In individual neurons, oscillations can appear either as oscillations in membrane potential or as rhythmic patterns of action potentials, which then produce oscillatory activation of post-synaptic neurons. At the level of neural ensembles, synchronized activity of large numbers of neurons can give rise to macroscopic oscillations, which can be observed in an electroencephalogram. Oscillatory activity in groups of neurons generally arises from feedback connections between the neurons that result in the synchronization of their firing patterns. The interaction between neurons can give rise to oscillations at a different frequency than the firing frequency of individual neurons. A well-known example of macros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Network
A neural network is a group of interconnected units called neurons that send signals to one another. Neurons can be either biological cells or signal pathways. While individual neurons are simple, many of them together in a network can perform complex tasks. There are two main types of neural networks. *In neuroscience, a '' biological neural network'' is a physical structure found in brains and complex nervous systems – a population of nerve cells connected by synapses. *In machine learning, an '' artificial neural network'' is a mathematical model used to approximate nonlinear functions. Artificial neural networks are used to solve artificial intelligence problems. In biology In the context of biology, a neural network is a population of biological neurons chemically connected to each other by synapses. A given neuron can be connected to hundreds of thousands of synapses. Each neuron sends and receives electrochemical signals called action potentials to its conne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Planning And Design
Network planning and design is an iterative process, encompassing #A network planning methodology, topological design, #A network planning methodology, network-synthesis, and #A network planning methodology, network-realization, and is aimed at ensuring that a new telecommunications network or service meets the needs of the subscriber and network operator, operator.Penttinen A., ''Chapter 10 – Network Planning and Dimensioning, Lecture Notes: S-38.145 - Introduction to Teletraffic Theory'', Helsinki University of Technology, Fall 1999. The process can be tailored according to each new network or service.Farr R.E., ''Telecommunications Traffic, Tariffs and Costs – An Introduction For Managers'', Peter Peregrinus Ltd, 1988. A network planning methodology A traditional network planning methodology in the context of business decisions involves five layers of planning, namely: * need assessment and resource assessment * short-term network planning * IT resource * long-term and m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gradient Network
In network science, a gradient network is a directed subnetwork of an undirected "substrate" computer network, network where each node (networking), node has an associated scalar potential and one out-link that points to the node with the smallest (or largest) potential in its neighborhood, defined as the union of itself and its Neighbourhood (graph theory), neighbors on the substrate network. Definition Transport takes place on a fixed network G = G(V,E) called the substrate graph. It has ''N'' nodes, V = \ and the set of edges E = \ . Given a node ''i'', we can define its set of neighbors in G by Si(1) = . Let us also consider a scalar field, ''h'' = defined on the set of nodes V, so that every node i has a scalar value ''h''''i'' associated to it. Gradient ∇''h''''i'' on a network: ∇h''i= (i, μ(i))'' i.e. the directed edge from ''i'' to ''μ(i)'', where ''μ''(''i'') ∈ Si(1) ∪ , and hμ has the maximum value in . ''Gradient network'' : ''∇G = ∇G (V, F) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Regulatory Network
A gene (or genetic) regulatory network (GRN) is a collection of molecular regulators that interact with each other and with other substances in the cell to govern the gene expression levels of mRNA and proteins which, in turn, determine the function of the cell. GRN also play a central role in morphogenesis, the creation of body structures, which in turn is central to evolutionary developmental biology (evo-devo). The regulator can be DNA, RNA, protein or any combination of two or more of these three that form a complex, such as a specific sequence of DNA and a transcription factor to activate that sequence. The interaction can be direct or indirect (through transcribed RNA or translated protein). In general, each mRNA molecule goes on to make a specific protein (or set of proteins). In some cases this protein will be structural, and will accumulate at the cell membrane or within the cell to give it particular structural properties. In other cases the protein will be an enz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaussian Network Model
The Gaussian network model (GNM) is a representation of a biological macromolecule as an elastic mass-and-spring (device), spring network to study, understand, and characterize the mechanical aspects of its long-time large-scale dynamics (mechanics), dynamics. The model has a wide range of applications from small proteins such as enzymes composed of a single protein domain, domain, to large Macromolecular Assembly, macromolecular assemblies such as a ribosome or a viral capsid. Protein domain dynamics plays key roles in a multitude of molecular recognition and cell signalling processes. Protein domains, connected by intrinsically disordered flexible linker domains, induce long-range allostery via Protein dynamics#Global flexibility: multiple domains, protein domain dynamics. The resultant dynamic modes cannot be generally predicted from static structures of either the entire protein or individual domains. The Gaussian network model is a minimalist, coarse-grained approach to stud ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynamic Single-frequency Networks
Dynamic single-frequency networks (DSFN) is a technique of using several transmitter antennas to transfer the same signal (macrodiversity) in orthogonal frequency-division multiplexing cellular networks. DSFN is based on the idea of single frequency networks, which is a group of radio transmitters that send the same signal simultaneously over the same frequency. The term originates from the broadcasting world, where a broadcast network is a group of transmitters that send the same TV or radio program. Digital wireless communication systems based on the OFDM modulation scheme are well-suited to SFN operation, since OFDM in combination with some forward error correction scheme can eliminate intersymbol interference and fading caused by multipath propagation without the use of complex equalization. The concept of DSFN implies the SFN grouping is changed dynamically over time, from timeslot to timeslot. The aim is to achieve efficient spectrum utilization for downlink unicast or mul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
