• Title/Summary/Keyword: Biological evolution

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Design of Distributed Node Scheduling Scheme Inspired by Gene Regulatory Networks for Wireless Sensor Networks (무선 센서 망에서 생체 유전자 조절 네트워크를 모방한 분산적 노드 스케줄링 기법 설계)

  • Byun, Heejung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.10
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    • pp.2054-2061
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    • 2015
  • Biologically inspired modeling techniques have received considerable attention for their robustness, scalability, and adaptability with simple local interactions and limited information. Among these modeling techniques, Gene Regulatory Networks (GRNs) play a central role in understanding natural evolution and the development of biological organisms from cells. In this paper, we apply GRN principles to the WSN system and propose a new GRN model for decentralized node scheduling design to achieve energy balancing while meeting delay requirements. Through this scheme, each sensor node schedules its state autonomously in response to gene expression and protein concentration, which are controlled by the proposed GRN-inspired node scheduling model. Simulation results indicate that the proposed scheme achieves superior performance with energy balancing as well as desirable delay compared with other well-known schemes.

Genetic Variations of Trichophyton rubrum Clinical Isolates from Korea

  • Yoon, Nam-Sup;Kim, Hyunjung;Park, Sung-Bae;Park, Min;Kim, Sunghyun;Kim, Young-Kwon
    • Biomedical Science Letters
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    • v.24 no.3
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    • pp.221-229
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    • 2018
  • Trichophyton rubrum is one of the well-known pathogenic fungi and causes dermatophytosis and cutaneous mycosis in human world widely. However, there are not an available sequence type (ST) classification methods and previous studies for T. rubrum until now. Therefore, currently, molecular biological tools using their DNA sequences are used for genotype identification and classification. In the present study, in order to characterize the genetic diversity and the phylogenetic relation of T. rubrum clinical isolates, five different housekeeping genes, such as actin (ACT), calmodulin (CAL), RNA polymerase II (RPB2), superoxide dismutase 2 (SOD2), and ${\beta}$-tubulin (BT2) were analyzed using by multilocus sequence typing (MLST). Also, DNA sequence analysis was performed to examine the differences between the sequences of Trichophyton strains and the identified genetic variations sequence. As a result, most of the sequences were shown to have highly matched rates in their housekeeping genes. However, genetic variations were found on three different positions of ${\beta}$-tubulin gene and were shown to have changed from $C{\rightarrow}G$ (1766), $G{\rightarrow}T$ (1876), and $C{\rightarrow}A$ (1886). To confirm the association with T. rubrum inheritance, a phylogenetic tree analysis was performed. It was classified as four clusters, but there was little significant correlation. Even so, MLST analysis is believed to be helpful for determining the genetic variations of T. rubrum in cases where there is more large-scale data accumulation. In conclusion, the present study demonstrated the first MLST analysis of T. rubrum in Korea and explored the possibility that MLST could be a useful tool for studying the epidemiology and evolution of T. rubrum through further studies.

Swell Correction of Shallow Marine Seismic Reflection Data Using Genetic Algorithms

  • park, Sung-Hoon;Kong, Young-Sae;Kim, Hee-Joon;Lee, Byung-Gul
    • Journal of the korean society of oceanography
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    • v.32 no.4
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    • pp.163-170
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    • 1997
  • Some CMP gathers acquired from shallow marine seismic reflection survey in offshore Korea do not show the hyperbolic trend of moveout. It originated from so-called swell effect of source and streamer, which are towed under rough sea surface during the data acquisition. The observed time deviations of NMO-corrected traces can be entirely ascribed to the swell effect. To correct these time deviations, a residual statics is introduced using Genetic Algorithms (GA) into the swell correction. A new class of global optimization methods known as GA has recently been developed in the field of Artificial Intelligence and has a resemblance with the genetic evolution of biological systems. The basic idea in using GA as an optimization method is to represent a population of possible solutions or models in a chromosome-type encoding and manipulate these encoded models through simulated reproduction, crossover and mutation. GA parameters used in this paper are as follows: population size Q=40, probability of multiple-point crossover P$_c$=0.6, linear relationship of mutation probability P$_m$ from 0.002 to 0.004, and gray code representation are adopted. The number of the model participating in tournament selection (nt) is 3, and the number of expected copies desired for the best population member in the scaling of fitness is 1.5. With above parameters, an optimization run was iterated for 101 generations. The combination of above parameters are found to be optimal for the convergence of the algorithm. The resulting reflection events in every NMO-corrected CMP gather show good alignment and enhanced quality stack section.

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Discrete Optimum Design of Ship Structures by Genetic Algorithm (유전적 알고리즘에 의한 선체 구조물의 이산적 최적설계)

  • Y.S. Yang;G.H. Kim;W.S. Ruy
    • Journal of the Society of Naval Architects of Korea
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    • v.31 no.4
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    • pp.147-156
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    • 1994
  • Though optimization method had been used for long time for the optimal design of ship structure, design variables in the most cases were assumed to be continuous real values or it was not easy to solve the mixed integer optimum design problems using the conventional optimization methods. Thus, it was often tried to use various initial starting points to locate the best optimum paint and to use special method such as branch and bound method to handle the discrete design variables in the optimization problems. Sometimes it had succeed, but the essential problems for dealing with the local optimum and discrete design variables was left unsolved. Hence, in this paper, Genetic Algorithms adopting the biological evolution process is applied to the ship structural design problem where the integer values for the number of stiffen design variables or the discrete values for the plate thickness variables would be more preferable in order to find out their effects on the final optimum design. Through the numerical result comparisons, it was found that Genetic Algorithm could always yield the global optimum for the discrete and mixed integer structural optimization problem cases even though it takes more time than other methods.

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A Survey of Genetic Programming and Its Applications

  • Ahvanooey, Milad Taleby;Li, Qianmu;Wu, Ming;Wang, Shuo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.4
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    • pp.1765-1794
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    • 2019
  • Genetic Programming (GP) is an intelligence technique whereby computer programs are encoded as a set of genes which are evolved utilizing a Genetic Algorithm (GA). In other words, the GP employs novel optimization techniques to modify computer programs; imitating the way humans develop programs by progressively re-writing them for solving problems automatically. Trial programs are frequently altered in the search for obtaining superior solutions due to the base is GA. These are evolutionary search techniques inspired by biological evolution such as mutation, reproduction, natural selection, recombination, and survival of the fittest. The power of GAs is being represented by an advancing range of applications; vector processing, quantum computing, VLSI circuit layout, and so on. But one of the most significant uses of GAs is the automatic generation of programs. Technically, the GP solves problems automatically without having to tell the computer specifically how to process it. To meet this requirement, the GP utilizes GAs to a "population" of trial programs, traditionally encoded in memory as tree-structures. Trial programs are estimated using a "fitness function" and the suited solutions picked for re-evaluation and modification such that this sequence is replicated until a "correct" program is generated. GP has represented its power by modifying a simple program for categorizing news stories, executing optical character recognition, medical signal filters, and for target identification, etc. This paper reviews existing literature regarding the GPs and their applications in different scientific fields and aims to provide an easy understanding of various types of GPs for beginners.

Sulfur Isotope Composition of Seafloor Hydrothermal Vents in the Convergent Plate Boundaries of the Western Pacific: A Role of Magma on Generation of Hydrothermal Fluid (서태평양 지판소멸대의 해저열수분출구에서 관찰되는 황동위원소 조성변화: 열수 생성의 다양성과 마그마의 역할)

  • Kim, Jong-Uk;Moon, Jai-Woon;Lee, Kyeong-Yong;Lee, In-Sung
    • Economic and Environmental Geology
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    • v.45 no.2
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    • pp.145-156
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    • 2012
  • Seafloor hydrothermal system occurs along the volcanic mid-ocean ridge, back-arc spreading center, and other submarine volcanic regions. The hydrothermal system is one of the fundamental processes controlling the transfer of energy and matter between crust/mantle and ocean; it forms hydrothermal vents where various deepsea biological communities are inhabited and precipitates metal sulfide deposits. Hydrothermal systems at convergence plate boundaries show diverse geochemical properties due to recycle of subducted material compared to simple systems at mid-ocean ridges. Sulfur isotopes can be used to evaluate such diversity in generation and evolution of hydrothermal system. In this paper, we review the sulfur isotope composition and geochemistry of hydrothermal precipitates sampled from several hydrothermal vents in the divergent plate boundaries in the western Pacific region. Both sulfide and sulfate minerals of the hydrothermal vents in the arc and backarc tectonic settings commonly show low sulfur isotope compositions, which can be attributed to input of magmatic $SO_2$ gas. Diversity in geochemistry of hydrothermal system suggests an active role of magma in the formation of seafloor hydrothermal system.

Hydrogen Gas Production by Fermentation from Various Sugars Using Clostridium butyricum NCIB 9576 (Clostridium butyricum NCIB 9576에 의한 당으로부터 혐기적 수소생산)

  • Kim, Mi-Sun;Moon, Kwang-Woong;Lee, In-Gu;Lee, Tae-Jin;Sung, Chang-Keun
    • Microbiology and Biotechnology Letters
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    • v.27 no.1
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    • pp.62-69
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    • 1999
  • Clostridium butyricum NCIB 9576 evolved hydrogen gas and produced various organic acids from glucose, lactose, starch, and glycerol. Total amount of hydrogen gas produced from 1 and 2% glucose were 630 and 950ml $H_2$/l-broth, respectively, for the first 24 hrs of incubation and the maximum hydrogen production rates were 42 and 94ml $H_2$/hr/1-broth, respectively. Teh initial pH 6.8 decreased to 4.2~4.5 during the first 12~16 hrs of fermentation when the pH was not controlled, resulting in ceasing the cell growth and hydrogen evolution and in degradation of 82 and 40% glucose after 24hrs of incubation from 1 and 2% glucose, respectively. When pH was controlled to 5.5, glucose was consumed completely and resulted in increasing hydrogen production approximately 38~50% compared to the experiments without the pH control. C. butyricum NCIB 9576 produced hydrogen gas approximately 644, 1,700 and 3,080 ml $H_2$/l-broth with 0.5, 1 and 2% lactose, respectively and the maximum hydrogen production rates were 41, 141 and 179ml $H_2$/hr/l-broth, respectively. All of the lactose added was degraded completely during fermentation even though pH was not controlled. C. butyricum NCIB 9576 produced 183 and 709ml $H_2$/l-broth with 0.1 and 0.5% starch for 48 hrs, respectively, when pH was not controlled. The maximum rates of hydrogen gas production were 43 and 186ml $H_2$/l-broth, respectively and 80~100% of starch added was fermented. Approximately 107ml $H_2$/l-broth was produced using 1% glycerol by C. butyricum NCIB 9576 and the pH was maintained higher than 6.1 during fermentation without pH control. The degradation of glucose, lactose, starch and glycerol by C. butyricum NCIB 9576 were affected by the pH of fermentation broth and the organic acids released during fermentation. The pH of feremtntation broth dropped to 4.2~4.6 after 12~14 hrs incubation when glucose was used as a substrate while pHs were maintained above pH 5 under the same experimental conditions when lactose, starch and glycerol were used. The organic solvents and acids produced during glucose fermentation were mainly ethanol, butyrate, acetate and a little of propionate, while butyrate was the main organic acids during the lactose, starch, and glycerol fermentation by C. butyricum NCIB 9576.

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The Evolution of Makeup Methods of Korean Women in Response to Changing Standards of Beauty in the Early 20th Century (20세기 초 미의식의 변화에 따른 국내여성들의 화장법)

  • Lee, Soon-Jae
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.8
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    • pp.1364-1377
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    • 2010
  • Although the human body is a biological subject with definite and distinctive physical features, its actualization and perception differs among societies. The aesthetics of the human body are based on diverse cultural perceptions that must be considered prior to design development. This study establishes the foundations of newly adopted concepts of beauty that are presumed to have been established in the first half of the twentieth century that continue to affect our mindset even now. The research includes human figures in the articles of women's magazines and cosmetic advertisements in the early $20^{th}$ century. The results are as follows: First, the change of perception in the human body: Instead of being a subject of preservation, the body has become a subject of sculpture with emphasis on health in the 1920's and on beauty in the 1930's. The recognition of the importance of the body has created intensive attention on physical training and an increased sense of hygiene. The body exposed to the public perceives itself through the eyes of others that alter one's own perception of oneself as well as become a target of evaluation. There is an additional emphasis on the exotic eroticism of a passive subordinate. Western culture became the standard for modernization along with the dissociation of traditional standards and values. Through the effect of education and western thinking, the awareness of women's rights and self-appreciation was developed. Second, ideal beauty can be summarized as follows: Unprocessed natural beauty was extolled as ideal in the 1920's, but the 1930's, it highlighted big eyes and an aquiline nose that are the characteristics of western women. Taking care of one's appearance was recognized as an important value for every social class. Cosmetics and skin care treatments promised soft and white skin. In contrast to western cosmetics, dark and shiny hair was highly favored. Exercising and traveling, differing seasonal and regional skin treatments were also widely accepted. In its initial stages, the research had originally assumed that the beginning of the twentieth century would be a time in which traditional concepts of beauty and new, westernized aesthetics coexisted. However, as the research progressed, it was clear that the idea of beauty had already adopted occidental ideals by that time. Thus, it seems necessary to continue the study on the shifting paradigms of beauty that must have occurred in the nineteenth and late twentieth century.

Phylogenetic implication of seed coat sculpturing in subtribe Agrimoniinae (Rosaceae) (장미과 짚신나물아족 종피형태의 계통분류학적 고찰)

  • Chung, Kyong-Sook;Hoang, Nguyet;Elisens, Wayne;Oh, Byoung Un
    • Korean Journal of Plant Taxonomy
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    • v.42 no.4
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    • pp.247-252
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    • 2012
  • Seed morphology in the subtribe Agrimoniinae (Rosaceae) was examined using scanning electron microscopy to identify distinct characters and evaluate their evolution in a phylogenetic framework for five genera in the subtribe: Agrimonia L., Aremonia Neck. ex Nestl., Hagenia J.F. Gmel., Leucosidea Eckl. & Zeyh., and Spenceria Trimen. All genera have one or two mature achenes in a fruiting hypanthium. In the seed coats, the cell shape, size, wall features, and sculpturing vary across genera. Of most significance is the presence of papillae structures in both Agrimonia and Aremonia. Through the mapping of papillae features onto phylogenetic trees, either one or two changes in seed coats are hypothesized. The phylogenetic tree inferred from four nuclear and six chloroplast regions of sequence data suggests that at least two steps of papillae sculpturing on seed coats are required. On the other hand, in the phylogenetic tree of a low-copy nuclear gene, one independent evolutionary step is postulated to explain the current character states. In the latter hypothesis, the seed coat sculpturing also supports a monophyletic relationship for cosmopolitan Agrimonia and European endemic Aremonia. The seed coat sculpturing provides valuable information for inferring phylogenetic relationships at the generic level in the subtribe Agrimoniinae.

Identification of SNPs in Highly Variable Lysozyme Gene in Korean Native Chicken Populations (한국 재래닭의 고변이 Lysozyme 유전자의 SNP 확인)

  • Hoque, M.R.;Kang, B.S.;Lim, H.K.;Choi, K.D.;Lee, J.H.
    • Korean Journal of Agricultural Science
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    • v.37 no.3
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    • pp.399-404
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    • 2010
  • Single nucleotide polymorphisms (SNPs) in chicken lysozyme (LYZ) gene were investigated in this study. The identification of SNPs in both exon and intron in LYZ gene has led to understanding of evolution for the domestic chicken populations. A total of 24 samples from two Korean native commercial chicken populations (CCPs) were used for the initial identification of SNPs by mixing three DNA samples for sequencing experiments. By comparing with red jungle fowl (RJF), two commercial chicken populations have 18 common polymorphisms. Between two commercial chicken populations, 15 polymorphisms were identified. Of the 33 polymorphisms identified, two indels (21 and 4 bp) were found. Whereas, only one polymorphism in exon 2 at the bp position 1426 was a non-synonymous substitution (p.Ala49Val), indicating the amino acid changes. The identified non-synonymous substitution (p.Ala49Val) is located close to the catalytic sites of the enzyme, which might affect its activity. In our investigation, the polymorphisms in LYZ gene can provide broad ideas for the variation of Korean native chicken populations from the ancestor of chicken breeds as well as the some biological functions of the LYZ gene.