• Title/Summary/Keyword: the theory of natural selection

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NOTES ON SELECTION PRINCIPLES IN TOPOLOGY (I): PARACOMPACTNESS

  • BABINKOSTOVA L.;KOCINAC LJ. D. R.;SCHEEPERS M.
    • Journal of the Korean Mathematical Society
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    • v.42 no.4
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    • pp.709-721
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    • 2005
  • G. Gruenhage gave a characterization of paracompactness of locally compact spaces in terms of game theory ([6]). Starting from that result we give another such characterization using a selective version of that game, and study a selection principle in the class of locally compact spaces and its relationships with game theory and a Ramseyan partition relation. We also consider a selective version of paracompactness.

A STUDY ON THE SELECTION OF ARTIFICIAL TEETH FOR THE EDENTULOUS PATIENTS IN KOREANS (한국인 무치악환자의 인공치아선택방법에 관한 연구)

  • Kim, Sung-Hun;Shin, Sang-Wan
    • The Journal of Korean Academy of Prosthodontics
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    • v.34 no.3
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    • pp.457-463
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    • 1996
  • An esthetically pleasing result in denture service is dependent upon several consideration. Esthetic considerations for the edentulous patient include tooth size, shape, arrangement, positioning, gingival contour, age, sex, personality differences, and ethnic type. Especially, the form of anterior artificial teeth is an important factor on the esthetics. The selection of artificaial teeth requires understanding and knowledge on physical and biologic factors and has to meet the indivisul esthetics and functional needs of each patient. However, the selection of artificial teeth is based on the large degree of subjective judgement of the dentist, Therefore, this is one of the most unscientific processes. Many attempts have been made to find a guideline for the selection of artificial teeth. Temperamental theory by White and Hall utillized with the physical characteristics such as body size, body form, color of eyes and hair, and disposition. SPA theory by Frush and Fisher utilized with the basis of sex, personalities, and age of the indivisual. There has not been provided for a guideline and study on the selection of artificial teeth for Koreans yet. This study was aimed to evaluate the William's typal matching theory in Koreans. 1. The facial forms of korean adult were ovoid(46.3%), square(36.7%) and tapered(17.0%) form. 2. The anatomic forms of natural maxillary incisors were ovoid(45.3%), tapered(31.3%), square(23.3%) form. 3. The forms of face and natural maxillary incisors were ovoid(21.9%), squared(11%), tapered(6.3%). 4. The natural maxillary incisors were similar in form to the facial form only in 39%. There was no correlation between the form of the face and the form of natural maxillary central inisors in Koreans. 5. Artificaial teeth which was selected according to the typal matching theory did not represent the form of the natural teeth in 61 per cents of the fatal, but it felt that they harmonized with the form of the patient's face and produced good results.

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Introduction to a Novel Optimization Method : Artificial Immune Systems (새로운 최적화 기법 소개 : 인공면역시스템)

  • Yang, Byung-Hak
    • IE interfaces
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    • v.20 no.4
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    • pp.458-468
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    • 2007
  • Artificial immune systems (AIS) are one of natural computing inspired by the natural immune system. The fault detection, the pattern recognition, the system control and the optimization are major application area of artificial immune systems. This paper gives a concept of artificial immune systems and useful techniques as like the clonal selection, the immune network theory and the negative selection. A concise survey on the optimization problem based on artificial immune systems is generated. The overall performance of artificial immune systems for the optimization problem is discussed.

Analysis of Evolutionary Content in High School Biology Textbook (고등학교 생물 교과서에서의 진화내용분석)

  • Kim, Hak-Hyun;Chang, Nam-Kee
    • Journal of The Korean Association For Science Education
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    • v.23 no.5
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    • pp.470-483
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    • 2003
  • This study analyzed the evolutionary content in 13 textbooks developed from the first to the 6th high school biology curriculum, The content analysis of textbooks, which were delineated nine component, was performed on the 80 evolutionary categories, According to the result, the proportion of the total evolutionary content in textbook increased from the textbooks developed by the Ist curriculum to the textbooks developed by the 6th curriculum, but the proportion of 'main narrative' in total evolutionary content was gradually decreased. It also showed that biology curriculum and points of view of textbook writers influenced on the proportion of evolutionary contents. On the whole, the topics of analysed textbooks exhibit insufficient diversity, Any categories- 'group selection', 'gene selection', 'gaps in fossil record', 'co-evolution', 'punctuated equilibrium', 'mosaic evolution', 'place of labor in human evolution', 'human race differentiation', 'criticism of "ontogeny recapitulates phylogeny", and 'human activities affecting evolution' - were not treated and others - 'theory of neutralism', 'theories of major episodes(excepting extinctions) found in the geologic time scale', 'sympatric speciation', 'clinal and area-effect speciation', 'polyploidy and evolution', 'gradualism' and 'evolution and origin of mammals' - were treated very lightly, the most emphasized topic was 'phylogeny in general' and 'formation of precells', 'miscellaneous' in the order of emphasis. 'Theory of natural selection' was lightly treated as just one of evolutionary theory though it should be emphasized as major theme of evolution. Also, the law of recapitulation, of which biologists doubt the validity, was discussed as an evidence of evolution in some textbooks. And the agents of genetic equilibrium disruption like genetic drift and migration were treated as of little importance. On the basis of above result, it was suggested that the textbook writers introduced the more meaningful evolutionary topics focused the theory of natural selection in explanation of evolution and evolution theory.

Free vibration analysis of FGM plates using an optimization methodology combining artificial neural networks and third order shear deformation theory

  • Mohamed Janane Allah;Saad Hassouna;Rachid Aitbelale;Abdelaziz Timesli
    • Steel and Composite Structures
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    • v.49 no.6
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    • pp.633-643
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    • 2023
  • In this study, the natural frequencies of Functional Graded Materials (FGM) plates are predicted using Artificial Neural Network (ANN). A model based on Third-order Shear Deformation Theory (TSDT) and FEM is used to train the ANN model. Different training methods are tested to simulate input and output dependency. As this is a parametric model, several architectures and optimization algorithms were tested. The proposed model allows us to minimize the CPU time to evaluate candidate material properties for FGM plate material selection and demonstrate their influence on dynamic behavior. Consequently, the time required for the FGM design process (candidate materials for material selection) and the geometric optimization of the FGM structure would remain reasonable. The ANN model can help industries to produce FGM plates with good mechanical properties of the selected materials. I addition, this model can be used to directly predict vibration behavior by testing a large number of FGM plates, representing all possible combinations of metals and ceramics in today's industry, without having to solve any eigenvalue problems.

A Method of Tending Practices for the Control of Stand Structure in Natural Mixed Stands (천연(天然) 혼효임분(混淆林分)의 구조조정(構造調整)을 위한 무육방법(撫育方法))

  • Shin, Man Yong;Bae, Sang Won;Lim, Joo-Hoon;Chun, Young Woo
    • Journal of Korean Society of Forest Science
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    • v.83 no.2
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    • pp.155-163
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    • 1994
  • This study was conduced to provide a method of tending practices for natural mixed stands, which have a possibility of inducing to selection cutting stand based on the analysis of stand structures. For this, first, diameter distribution for a balanced selection cutting stand was predicted using Q theory applied to natural stands. The method of estimating diminution ratio coefficient Q is presented. The possible tending practice method which could be adopted to natural stands is discussed based on two different diameter distributions and side conditions.

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Development of an Effective Strategy to Teach Evolution

  • Ha, Min-Su;Cha, Hee-Young
    • Journal of The Korean Association For Science Education
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    • v.31 no.3
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    • pp.440-454
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    • 2011
  • This study proposes a new instructional strategy and corresponding materials designed from various alternative frameworks to help students understand evolution as a biologically acceptable theory. Biology teachers have normally taught the evolutionary mechanism by means of comparing Lamarckism with natural selection. In this study, a new instructional strategy in which the Lamarckian explanation is first excluded because Lamarckism is known to be subsumed in a learner's cognitive structure as a strong preconception of evolution is suggested for teaching evolution. After mutation theory is introduced, Darwinism including natural selection is explained separately during the next class hour. Corresponding instructional materials that aid student understanding of the evolutionary mechanism were developed using recently published articles on human genetic traits as scientific evolutionary evidence instead of the traditional evolutionary subject matter, giraffe neck. Evolutionary evidence from human genetic traits allows students to exclude anthropocentric thoughts effectively and raise concern for the phenomenon of evolution positively. The administered instructional strategy and materials in this research improved student conception, concern, and belief of evolution and it is believed that they helped students understand the evolutionary mechanism effectively.

From So Simple a Beginning, From So Simple a Theory

  • Choe, Jae-Chun
    • Journal of Ecology and Environment
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    • v.32 no.4
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    • pp.217-220
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    • 2009
  • The year of 2009 marks the $200^{th}$ anniversary of Charles Darwin's birth and the 150th anniversary of the publication of his book, On the Origin of Species. Having survived the 150 years of hardening and tempering, Darwin's theory of natural selection is now more comprehensive and powerful than ever. It casts its shadow over nearly all academic disciplines and societal sectors. It truly revolutionized the way we look at the world and ourselves. In the midst of Darwinian revolution, however, Korea remains as a backward country as far as the understanding of Darwin and his theory is concerned. A variety of intellectual activities organized to celebrate the Year of Darwin is helping to narrow the gap. This article summarizes the kinds of such activities held in Korea this year and explains how Darwin made all this possible. To paraphrase the famous quotation by Theodosius Dobzhansky, I now dare to say, "Nothing in life makes sense except in the light of evolution".

Determinant Paths of Recreation Forest Visitors' Satisfaction and Revisit by Expectation-Disconfirmation Theory (기대불일치이론에 의한 자연휴양림 이용객의 만족 및 재방문 결정경로)

  • Han, Sang-Yoel
    • Journal of Korean Society of Forest Science
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    • v.95 no.3
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    • pp.291-298
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    • 2006
  • This study analyzes how expectations, perceived performance and expectation-disdonfirmation of the recreation-forest visitors affect their satisfaction and revisit using path analysis. These results which would maximize visitors' satisfaction and revisit will enhance recreational forest management. As the results, factors of expectation-disconfirmation positively effected visit satisfaction are experience-facilities, natural resources, access and valley factors. In addition, natural resources factor effects positively their selection-satisfaction. Also, visit-satisfaction and selection-satisfaction effect positively to their revisit intention. This result show seeking the visitors' satisfaction through recreation-forest manager try to expectation-disconfirmation of experience-facilities, natural resources, access and valley factors exchange to positive expectation-disconfirmation.

A Study on the Site Selection and Orientation of Western House in Cheongju (청주(淸州) 탑동양관(塔洞洋館)의 입지선정(立地選定) 및 좌향(坐向)에 관한 연구(硏究))

  • Seo, Hyang-Soon;Lee, Min-Kyoung;Kim, Tai-Young
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2008.04a
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    • pp.197-202
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    • 2008
  • The purpose of this study is to clarify the site selection and orientation which have affected the western missionaries in construction of the first western house in Cheongju area. The results of this study are as follows; In the site selection, they chose Tap-Dong hill, by finding the higher position and taking a fine view of all natural elements, because the alters like the tomb of Confucius, the existing settlement Godang village, Dang Mt. are already located around this area. And also it was that they could easily go into Tap-Dong hill through the existing alleys, These alleys, generated near the original road of Tap-Dong hill, are developed to modern road system. These alleys affect western house's entrance and orientation. In deciding the orientation of house, korean people prefer to south and east by considering Feng-shui theory; otherwise western house, specially the first house has a southwestern aspect, because the western missionaries have a preference for the topography, entry, and view than a house facing south.

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