• Title, Summary, Keyword: evolution

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The Evolution of Products (제품의 진화)

  • 이홍구
    • Archives of design research
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    • v.14 no.4
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    • pp.137-146
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    • 2001
  • The purpose of the study is to explore and understand the product development through the theory of evolution. For the purpose of the study, an evolution mechanism was set up in which the products were applied with. The results showed three distinguishable types of product evolution 'the evolution of functions','the evolution of forms'and 'the evolution of symbols what the products represent'. In order to answer the research questions, , , , the research was carried out in three ways: firstly, some ideas of product evolution were looked closely through existing researches; secondly, the study explored the idea of evolution mechanism being a natural process like an organic system; finally by applying various products with the evolution mechanism, different patterns of product evolution were classified. The results of the study can be summarised as follows: ${\bullet}$ The evolution mechanism in this study can be defined as an 'organic system'that consists of the causes of evolution'(based on the needs and the willingness to have pleasure), 'the point of evolving'(based on a degree of imperfection) and 'the motive of evolution'(based on the readiness to make profit). ${\bullet}$ The evolution mechanism seems to suggest three different patterns in product evolution,'the evolution of functions', 'the evolution of forms' and 'the evolution of symbols'

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SOME PROPERTIES OF EVOLUTION ALGEBRAS

  • Camacho, L.M.;Gomez, J.R.;Omirov, B.A.;Turdibaev, R.M.
    • Bulletin of the Korean Mathematical Society
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    • v.50 no.5
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    • pp.1481-1494
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    • 2013
  • The paper is devoted to the study of finite dimensional complex evolution algebras. The class of evolution algebras isomorphic to evolution algebras with Jordan form matrices is described. For finite dimensional complex evolution algebras the criterium of nilpotency is established in terms of the properties of corresponding matrices. Moreover, it is proved that for nilpotent $n$-dimensional complex evolution algebras the possible maximal nilpotency index is $1+2^{n-1}$.

Queen-bee and Mutant-bee Evolution for Genetic Algorithms

  • Jung, Sung-Hoon
    • Journal of Korean Institute of Intelligent Systems
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    • v.17 no.3
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    • pp.417-422
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    • 2007
  • A new evolution method termed queen-bee and mutant-bee evolution is based on the previous queen-bee evolution [1]. Even though the queen-bee evolution has shown very good performances, two parameters for strong mutation are added to the genetic algorithms. This makes the application of genetic algorithms with queen-bee evolution difficult because the values of the two parameters are empirically decided by a trial-and-error method without a systematic method. The queen- bee and mutant-bee evolution has no this problem because it does not need additional parameters for strong mutation. Experimental results with typical problems showed that the queen-bee and mutant-bee evolution produced nearly similar results to the best ones of queen-bee evolution even though it didn't need to select proper values of additional parameters.

Students' Knowledge, Acceptance of Theory of Evolution and Epistemology: Cross-sectional Study of Grade Level Differences

  • Kim, Sun Young
    • Journal of Science Education
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    • v.40 no.1
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    • pp.1-16
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    • 2016
  • The purpose of this study is to explore the variables of knowledge, acceptance of theory of evolution and epistemology that could be keys for teaching and learning the theory of evolution within school contexts, and to suggest instructional tips for teaching evolution in relation to the grade levels of education. This cross-sectional study examined the grade level differences (8th, 11th, and preservice teachers) of four variables: evolutionary knowledge; acceptance of theory of evolution; and both domain-specific epistemology (nature of science in relation to evolution) and context-specific epistemology (scientific epistemological views) and their relationships. This study, then, built conceptual models of each grade level students' acceptance of theory of evolution among the factors of evolutionary knowledge and epistemology (both domain-specific and context-specific). The results showed that the scores of evolutionary knowledge, evolution in relation to NOS, and scientific epistemology increased as the grade levels of education go up(p<.05) except the scores of acceptance of theory of evolution(p>.05). In addition, the 8th graders' and the 11th graders' acceptance of evolutionary theory was most explained by 'evolution in relation to NOS', while the preservice teachers' acceptance of evolutionary theory was most explained by evolutionary knowledge. Interestingly, 'scientific epistemological views' were only included for the 8th graders, while evolutionary knowledge and 'evolution in relation to NOS' (context-specific epistemology) were included in explaining all the level of students' acceptance of evolutionary theory. This study implicated that when teaching and learning of the theory of evolution in school contexts, knowledge, acceptance of evolutionary theory and epistemology could be considered appropriately for the different grade levels of students.

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Sliding Mode Control for Robot Manipulator Usin Evolution Strategy (Evolution Strategy를 이용한 로봇 매니퓰레이터의 슬라이딩 모드 제어)

  • 김현식;박진현;최영규
    • 제어로봇시스템학회:학술대회논문집
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    • pp.379-382
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    • 1996
  • Evolution Strategy is used as an effective search algorithm in optimization problems and Sliding Mode Control is well known as a robust control algorithm. In this paper, we propose a Sliding Mode Control Method for robot manipulator using Evolution Strategy. Evolution Strategy is used to estimate Sliding Mode Control Parameters such as sliding surface gradient, continuous function boundary layer, unknown plant parameters and switching gain. Experimental results show the proposed control scheme has accurate and robust performances with effective search ability.

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Performance Improvement of Evolution Strategies using Reinforcement Learning

  • Sim, Kwee-Bo;Chun, Ho-Byung
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.1 no.1
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    • pp.125-130
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    • 2001
  • In this paper, we propose a new type of evolution strategies combined with reinforcement learning. We use the variances of fitness occurred by mutation to make the reinforcement signals which estimate and control the step length of mutation. With this proposed method, the convergence rate is improved. Also, we use cauchy distributed mutation to increase global convergence faculty. Cauchy distributed mutation is more likely to escape from a local minimum or move away from a plateau. After an outline of the history of evolution strategies, it is explained how evolution strategies can be combined with the reinforcement learning, named reinforcement evolution strategies. The performance of proposed method will be estimated by comparison with conventional evolution strategies on several test problems.

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The Role of a Floral Identity Gene LFY in Plant Morphological Evolution

  • Park, Young-Doo;Yoon, Ho-Sung
    • Korean Journal of Plant Taxonomy
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    • v.37 no.4
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    • pp.323-333
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    • 2007
  • The degree to which parallel evolution utilizes the same genetic mechanisms indicates the degree to which developmental processes constrain or channel phenotypic evolution. A transgenetic strategy was used to elucidate the role of one floral meristem identity gene, LEAFY (LFY), in the evolution of rosette flowering, a plant architecture that has evolved in parallel in several lineages of the mustard family, Brassicaceae. The LFY genes from three rosette flowering species were cloned and introduced into a species with the ancestral architecture, and results indicated that changes at the LFY locus contributed to the evolution of rosette flowering in two of the three lineages, but that in each lineage a different set of genetic partners was involved. Also, LFY was shown to play a role in the evolution of flower size. Transgenetic strategy may be useful in the study of plant morphological evolution and parallelism.

Performance Improvement of Genetic Algorithms by Strong Exploration and Strong Exploitation (감 탐색과 강 탐험에 의한 유전자 알고리즘의 성능 향상)

  • Jung, Sung-Hoon
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • pp.233-236
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    • 2007
  • A new evolution method for strong exploration and strong exploitation termed queen-bee and mutant-bee evolution is proposed based on the previous queen-bee evolution [1]. Even though the queen-bee evolution has shown very good performances, two parameters for strong mutation are added to the genetic algorithms. This makes the application of genetic algorithms with queen-bee evolution difficult because the values of the two parameters are empirically decided by a trial-and-error method without a systematic method. The queen-bee and mutant-bee evolution has no this problem because it does not need additional parameters for strong mutation. Experimental results with typical problems showed that the queen-bee and mutant-bee evolution produced nearly similar results to the best ones of queen-bee evolution even though it didn't need to select proper values of additional parameters.

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Effect of Photosynthesis on Ozone-Induced Ethylent Evolution from Tomato Plants (토마토 식물에 있어서 광합성이 유존유동성의 에틸렌 생성에 미치는 영향)

  • 배공영
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.3
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    • pp.307-314
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    • 1996
  • The rate of evolution of ethylent by tomato plants was rapidly increased by ozone fumigation. In the present study, the mechanism of ethylent evolution by ozone was investigated in experiments with aminoethoxyvinylglycine (AVG) and tiron, which inhibit the formation of ethylene and peroxidation of lipids, respectively. Pretreatment with AVG significantly inhibited the ozone-induced ethylent evolution, but the treatment of plants with tiron did not inhibit. These results indicate that the induction of the evolution of ethylene by ozone involves the pathway via aminocyclopropane-1-carboxylate (ACC), while not released as a result of the peroxidation of lipids. Ozone-induced ethylent evolution was greater in dar- than light-incubated, intact tomato plants. The difference between dark- and light-ethylene evolution was examined with diuron, an inhibitor of photosynthetic electron transport. The inhibitor treatment promoted ethylent evolution. These results suggest that ethylent retention and metabolism in plants were regulated by internal $CO_2$ levels which, in turn, were controlled in large part by photosynthesis. Thus, ethylene was retained in illuminated leaf tissue under low intenal $CO_2$ concentration which may develop in a sealed container without exogenously supplied $CO_2$.

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Ethylene Evolution in Tomato Plants by Ozone in Relation to Leaf Injury (토마토 오존처리에 의한 에틸렌 생성과 가시 장해 발현과의 관계)

  • 배공영;이용범
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.3
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    • pp.333-340
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    • 1996
  • The relationship between ozone-induced damages and ethylend evolution was examined in tomato plants fumigated with ozone of 0.2 $\mu\ell/\ell$. The rate of evolution of ethylent by tomato plants was enhanced by ozone fumigation. Pretreatment of leaves with aminoethoxyvinylglycine (AVG), an inhibitor of ethylene evolution, significantly inhibited the evolution of ethylene that was induced by ozone and concomitantly reduced the extent of ozone-induced visible damage to leaves. Treatment with 2,5-norbonadiene (NBD), and inhibitor of the action of ethylene, strongly reduced the extent of visible damage caused by ozone, even though it did not suppress the evolution of ethylene. These results indicated that ethylene might play an important role in ozone-induced plant injuries at relatively short terms of ozone fumigation. Next, we examined the effect of tiron, a scanvenger of the free-radical, on evolution of ethylene and leaf injury caused by ozone. Tiron treatment strongly reduced the extent of ozone-induced injury, but had not inhibitory effect on the evolution of ethylene from tomato leaves. This result suggests the involvement of free-radical, such as superoxide radicals, in induction of injuries caused by ozone.

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