(R)evolutionary memory in Tambov (1991–2017) 1

2019 ◽  
pp. 242-269
Author(s):  
Bartłomiej Gajos
Keyword(s):  
2009 ◽  
Vol 41 (2) ◽  
pp. 142-143 ◽  
Author(s):  
Michael M Desai
Keyword(s):  

Author(s):  
B.K. Lebedev ◽  
O.B. Lebedev ◽  
A.A. Zhiglaty

In this paper, the crystal plan is formed by the recursive use of a "guillotine cut". To set the plan means to set the structure of the binary tree of the cuts, i.e. sequence of binary cuts; for internal tree vertices, to indicate the type of the cut H or V; to number the leaves of the tree and indicate the orientation of the modules. The structure of the binary tree of the cuts can be set using the Polish expression on the base of the alphabet A = {M, TR}, where the set of letters M = {mi|i = 1, 2, ..., nМ} corresponds to the leaves of the section tree (regions), and the set R = {H, V} corresponds to the cuts. We propose a way and methods for solving the problems of planning VLSI based on a modified ant colony. The task of synthesizing the section tree of the plan with the choice of types of sections, identification and orientation of the modules in the work is reduced to the task of forming a modified Polish expression with the identification of elements on the composite model of the solution space, including many alternative vertices. To keep the collective evolutionary memory during the life of the ant population and to form the solution of the problem, we use the complete graph G = (X, U) with alternative vertex states. Each vertex may be in one of two alternative states, i.e., α or β, corresponding to the orientation of the module or the type of the cut. The task of synthesizing the Polish expression is formulated as the task of finding the least-cost route on the solution search graph G = (X, U). A distinctive feature is that when building a route, simultaneously with the choice of the vertex xi∈ X, the state of this vertex is selected. The time complexity of the algorithm is O(n2). Experiments have shown that for large dimensions, the time indicators of the developed algorithm exceed those of the compared algorithms with the best values of the objective function.


2018 ◽  
Vol 97 (4) ◽  
Author(s):  
Md. Zulfikar Ali ◽  
Ned S. Wingreen ◽  
Ranjan Mukhopadhyay

2007 ◽  
Vol 4 (1) ◽  
pp. 1-11 ◽  
Author(s):  
J. Henderiks ◽  
R. E. M. Rickaby

Abstract. An urgent question for future climate, in light of increased burning of fossil fuels, is the temperature sensitivity of the climate system to atmospheric carbon dioxide (pCO2). To date, no direct proxy for past levels of pCO2 exists beyond the reach of the polar ice core records. We propose a new methodology for placing an upper constraint on pCO2 over the Cenozoic based on the living geological record. Specifically, our premise is that the contrasting calcification tolerance of various extant species of coccolithophore to raised pCO2 reflects an "evolutionary memory" of past atmospheric composition. The different times of first emergence of each morphospecies allows an upper constraint of past pCO2 to be placed on Cenozoic timeslices. Further, our hypothesis has implications for the response of marine calcifiers to ocean acidification. Geologically "ancient" species, which have survived large changes in ocean chemistry, are likely more resilient to predicted acidification.


2021 ◽  
pp. 1-23
Author(s):  
Léo Françoso Dal Piccol Sotto ◽  
Franz Rothlauf ◽  
Vinçcius Veloso de Melo ◽  
Márcio P. Basgalupp

Abstract Linear Genetic Programming (LGP) represents programs as sequences of instructions and has a Directed Acyclic Graph (DAG) dataflow. The results of instructions are stored in registers that can be used as arguments by other instructions. Instructions that are disconnected from the main part of the program are called non-effective instructions, or structural introns. They also appear in other DAG-based GP approaches like Cartesian Genetic Programming (CGP). This paper studies four hypotheses on the role of structural introns: non-effective instructions (1) serve as evolutionary memory, where evolved information is stored and later used in search, (2) preserve population diversity, (3) allow neutral search, where structural introns increase the number of neutral mutations and improve performance, and (4) serve as genetic material to enable program growth. We study different variants of LGP controlling the influence of introns for symbolic regression, classification, and digital circuits problems. We find that there is (1) evolved information in the non-effective instructions that can be reactivated and that (2) structural introns can promote programs with higher effective diversity. However, both effects have no influence on LGP search performance. On the other hand, allowing mutations to not only be applied to effective but also to noneffective instructions (3) increases the rate of neutral mutations and (4) contributes to program growth by making use of the genetic material available as structural introns. This comes along with a significant increase of LGP performance, which makes structural introns important for LGP.


2007 ◽  
Vol 4 (3) ◽  
pp. 323-329 ◽  
Author(s):  
J. Henderiks ◽  
R. E. M. Rickaby

Abstract. An urgent question for future climate, in light of increased burning of fossil fuels, is the temperature sensitivity of the climate system to atmospheric carbon dioxide (pCO>sub>2). To date, no direct proxy for past levels of pCO2 exists beyond the reach of the polar ice core records. We propose a new methodology for placing a constraint on pCO2 over the Cenozoic based on the physiological plasticity of extant coccolithophores. Specifically, our premise is that the contrasting calcification tolerance of various extant species of coccolithophore to raised pCO2 reflects an "evolutionary memory" of past atmospheric composition. The different times of evolution of certain morphospecies allows an upper constraint of past pCO2 to be placed on Cenozoic timeslices. Further, our hypothesis has implications for the response of marine calcifiers to ocean acidification. Geologically "ancient" species, which have survived large changes in ocean chemistry, are likely more resilient to predicted acidification.


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