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Nothing is impossible , if distributed.

 
 
 

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【6.033】【notes】REC : The Architecture of Complexity  

2012-08-08 16:07:47|  分类: Distributed |  标签: |举报 |字号 订阅

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all of the following things are cited from Simon's "The Architecture of Complexity"
THE DESCRIPTION OF COMPLEXITY 
     Near Decomposability and Comprehensibility
     Many complex systems have a nearly decomposable, hierarchic structure is a major facilitating factor enabling us to understand , to describe ,and even to "see" such systems and their parts. Or perhaps the proposition shoud be put the other way round. If there are important systems in the world that are complex without being hierarchic, they may to a considerable extent escape our observation and our understanding . Analysis of their behavior would involve such detailed knowledge and calculation of the interactions of their elementary parts that it would be  beyond our capacities of memory or computation.
     
     Simple Descriptions of Complex Systems
     If a complex system is completely unredundant -- if no aspect of its structure can be inferred from any other -- then it its own simplest description. The hierarchic structures have a high degree of redundancy, hence can often be described in economical terms. 
     The forms of redundancy : 
     1) Hierarchic systems are usually composed of only a few different kind of subsystems, in various combinations and arrangements.
     2) Hierarchic systems are often nearly decomposable.
     3) By appropriate "recoding ", the redundancy that is present but unobvious in the structure of a complex system can often be made patent.

     State Descriptions and Process Descriptions
     "A circle is the locus of all points equidistant from a given point" , " To construct a circule, rotate a compass with one arm fixed until the other arm has returned to its starting point". The first sentence is a state description of a cricle, the second a process descritption. Pictures , blueprints, most dirgrams, chemical structural formulae are state descriptions.  Recipes, differential equations, equations for chemical reactions are process descriptions.
     Given a desired state of affairs and an existing state of affairs, the task of an adaptive organism is to find the difference between these two states, and then to find the correlating process that will erase the difference.
     
     
     
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