Dysfunctions of Real-Time Computation--论文代写范文精选

异速生长的扩展，这意味着一个重要的需要调整架构问题，实时计算结构及其环境是一个统一的现象,和环境通常的特质。未能认识到这些问题的深度可能会产生一个无情的链,大规模并行机器的使用，提出了实时动态过程的监管。下面的paper代写范文进性讲述。

Abstract 
Cognitive biological structures, social organizations, and computing machines operating in real time are subject to Rate Distortion Theorem constraints driven by the homology between information source uncertainty and free energy density. This exposes the unitary structure/environment system to a relentless entropic torrent compounded by sudden large deviations causing increased average distortion between intent and impact, particularly as demands escalate. The phase transitions characteristic of information phenomena suggest that, rather than graceful decay under increasing load, these structures will undergo punctuated degradation akin to spontaneous symmetry breaking in physical systems. 

Rate distortion problems, that also affect internal structural dynamics, can become synergistic with limitations equivalent to the inattentional blindness of natural cognitive processes. These mechanisms, and their interactions, are unlikely to scale well, so that, depending on architecture, enlarging the structure or its duties may lead to a crossover point at which added resources must be almost entirely devoted to ensuring system stability – a form of allometric scaling familiar from biological examples. This suggests a critical need to tune architecture to problem type and system demand. A real-time computational structure and its environment are a unitary phenomenon, and environments are usually idiosyncratic. Thus the resulting path dependence in the development of pathology could often require an individualized approach to remediation more akin to an arduous psychiatric intervention than to the traditional engineering or medical quick fix. Failure to recognize the depth of these problems seems likely to produce a relentless chain of the Chernobyl-like failures that are necessary, but often insufficient, for remediation under our system. 
Key Words cognition, entropy, free energy, groupoid, information theory, large deviations, Morse Theory, no free lunch, parallel, pathology, rate distortion, scaling laws, spontaneous symmetry breaking

Introduction 
Massively parallel machines are currently used or proposed for the regulation of dynamic processes in real time. Potential critical applications include financial systems and communications networks, refineries, nuclear reactors, chemical factories, large scale traffic control, the piloting of individual vehicles, and so on. Many physiological and psychological systems in higher animals, including man, are both cognitive in the Atlan/Cohen sense (Atlan and Cohen, 1998), and also operate rapidly enough to be classified as real-time. These include immune and blood pressure regulation mechanisms, cognitive gene expression, and higher order cognition and consciousness (e.g., Baars, 2005; Dretske, 1981, 1988, 1994; Wallace, 2005; Wallace and Wallace, 2008). Social structures ranging from animal hive colonies to modern giant corporations, their institutional networks of competition and cooperation, and the associated political empires which they dominate, engage in elaborate processes of distributed cognition that must also operate in real-time (e.g., Wallace and Fullilove, 2008). 

Here we will examine limits placed on real-time systems by the Rate Distortion Theorem and by homologies with thermodynamic free energy, and the manner in which those limits can produce characteristic patterns of system degradation and failure. We begin with a highly formal description of phase transitions in cognitive systems, extending perspectives from physical theory to ‘necessary conditions’ statistical models of cognitive process based on the asymptotic limits of information theory. Landau’s famous insight regarding phase change in physical systems was that second order phase transitions are usually in the context of a significant alteration in symmetry, with one phase being far more symmetric than the other (e.g., Pettini, 2007; Landau and Lifshitz, 2007). 

A symmetry is lost in the transition, a phenomenon called spontaneous symmetry breaking. The greatest possible set of symmetries in a physical system is that of the Hamiltonian describing its energy states. Usually states accessible at lower temperatures will lack the symmetries available at higher temperatures, so that the lower temperature phase is less symmetric: The randomization of higher temperatures ensures that higher symmetry/energy states will then be accessible to the system. A change in symmetry must, of necessity, be discontinuous, so that lowering temperatures inevitably leads to punctuated transitions in such systems. 

One can indeed construct a good phenomenological model using group representations (Pettini, 2007). What of biological and cognitive structures that cannot easily be described using elementary physical models or simple group symmetries? What of systems where the physical temperature is not the determining factor in punctuated change? We will be concerned here with systems having associated information sources that can be described in terms of groupoids, a natural generalization of groups described in the Appendix that is finding increasingly widespread use in biology and cognitive theory (e.g., Golubitsky and Stewart, 2006). In particular, as we argue below, a broad swath of cognitive phenomena can be characterized in terms of information sources (e.g., Wallace, 2005; Fullilove and Wallace, 2008). Mathematical preliminaries require a brief exploration of the homology between information and free energy.

Free Energy Density and Information Source Uncertainty Information source uncertainty can be defined in several ways. Khinchin (1957) describes the fundamental ‘E-property’ of a stationary, ergodic information source as the ability, in the limit of infinity long output, to classify strings into two sets; [1] a very large collection of gibberish which does not conform to underlying rules of grammar and syntax, in a large sense, and which has near-zero probability, and [2] a relatively small ‘meaningful’ set, in conformity with underlying structural rules, having very high probability. (paper代写)

51Due网站原创范文除特殊说明外一切图文著作权归51Due所有；未经51Due官方授权谢绝任何用途转载或刊发于媒体。如发生侵犯著作权现象，51Due保留一切法律追诉权。
更多paper代写范文欢迎访问我们主页 www.51due.com 当然有paper代写需求可以和我们24小时在线客服 QQ:800020041 联系交流。-X(paper代写)