• 한국수학교육학회지시리즈B:순수및응용수학
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• 제17권1호
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• pp.93-106
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• 2010

We employ the methods of Lattice Dynamical System to establish a global model extending the Walrasian evolutionary cobweb model in an independent single local market to the global market evolution over an infinite chain of many local markets with interaction of each other through a diffusion of prices between them. For brevity of the model, we assume linear decreasing demands and logistic supplies with naive predictors, and investigate the traveling wave behaviors of global price dynamics and show that their dynamics are conjugate to those of H$\acute{e}$non maps and hence can exhibit complicated behaviors such as period-doubling bifurcations, chaos, and homoclic orbits etc.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제16권2호
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• pp.243-254
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• 2009

The main purpose of this paper is to use the methods of Lattice Dynamical System to establish a global model, which extends the Walrasian evolutionary cobweb model in an independent single local market to the global market evolution over an infinite chain of many local markets interacting each other through a diffusion of prices between them. For brevity of the model, we assume linear decreasing demands and quadratic supplies with naive predictors, and investigate the spatially homogeneous global price dynamics and show that the dynamics is topologically conjugate to that of well-known logistic map and hence undergoes a period-doubling bifurcation route to chaos as a parameter varies through a critical value.

• 자원환경지질
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• 제55권6호
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• pp.597-616
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• 2022

The Chungnam basin is a crucial area for studying the Mesozoic crustal evolutionary history of the Korean Peninsula. This study reports the revised geology and new isotopic ages from the northeastern Chungnam Basin based on detailed geological mapping and LA-ICP-MS zircon U-Pb analysis. Our renewed geologic map defines intra-basin, basin-bounding, and basement fault systems closely related to hydrothermal gold-bearing quartz vein injections. Here, we propose the directions of (micro)structural and geochronological future work to address issues on the relationship between the tectonic process, basin evolution, and hydrothermal fluid migration in the southwestern Korean Peninsula.

• 천문학회보
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• 제45권1호
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• pp.66.2-66.2
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• 2020

We propose a deep learning analysis technique with a convolutional neural network (CNN) to predict the evolutionary track of the Epoch of Reionization (EoR) from the 21-cm differential brightness temperature tomography images. We use 21cmFAST, a fast semi-numerical cosmological 21-cm signal simulator, to produce mock 21-cm maps between z = 6 ~ 13. We then apply two observational effects, such as instrumental noise and limit of (spatial and depth) resolution somewhat suitable for realistic choices of the Square Kilometre Array (SKA), into the 21-cm maps. We design our deep learning model with CNN to predict the sliced-averaged neutral hydrogen fraction from the given 21-cm map. The estimated neutral fraction from our CNN model has great agreement with the true value even after coarsely smoothing with broad beam size and frequency bandwidth and heavily covered by noise with narrow beam size and frequency bandwidth. Our results show that the deep learning analyzing method has the potential to reconstruct the EoR history efficiently from the 21-cm tomography surveys in future.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2003년도 제2차 연례학술대회 발표논문집
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• pp.183-192
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• 2003

With the availability of complete whole-genomes such as the human, mouse, fugu and chimpanzee chromosome 22, comparative analysis of large genomes from cross-species at varying evolutionary distances is considered one of a powerful approach for identifying coding and functional non-coding sequences. Here we describe a fast and efficient global alignment method especially for large genomic regions over mega bases pair. We used an approach for identifying all similarity regions by HSP (Highest Segment Pair) regions using local alignments and then large syntenic genome based on the both extension of anchors at HSP regions in two species and global conservation map. Using this alignment approach, we examined rearrangement loci in human chromosome 21 and chimpanzee chromosome 22. Finally, we extracted syntenic genome 30 Mb of human chromosome 21 with chimpanzee chromosome 22, and then identified genomic rearrangements (deletions and insertions ranging h size from 0.3 to 200 kb). Our experiment shows that all jnsertion/deletion (indel) events in excess of 300 bp within chimpanzee chromosome 22 and human chromosome 21 alignments in order to identify new insertions that had occurred over the last 7 million years of evolution. Finally we also discussed evolutionary features throughout comparative analyses of Ka/ks (non-synonymous / synonymous substitutions) rate in orthologous 119 genes of chromosome 21 and 53 genes of MHC-I class in human and chimpanzee genome.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권5호
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• pp.2277-2298
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• 2019

Adaptive learning in e-learning has garnered researchers' interest. In it, learning resources could be recommended automatically to achieve a personalized learning experience. There are various ways to realize it. One of the realistic ways is adaptive learning path recommendation, in which learning resources are provided according to learners' requirements. This paper summarizes existing works and proposes an innovative approach. Firstly, a learner-centred concept map is created using graph theory based on the features of the learners and concepts. Then, the approach generates a linear concept sequence from the concept map using the proposed traversal algorithm. Finally, Learning Objects (LOs), which are the smallest concrete units that make up a learning path, are organized based on the concept sequences. In order to realize this step, we model it as a multi-objective combinatorial optimization problem, and an improved immune algorithm (IIA) is proposed to solve it. In the experimental stage, a series of simulated experiments are conducted on nine datasets with different levels of complexity. The results show that the proposed algorithm increases the computational efficiency and effectiveness. Moreover, an empirical study is carried out to validate the proposed approach from a pedagogical view. Compared with a self-selection based approach and the other evolutionary algorithm based approaches, the proposed approach produces better outcomes in terms of learners' homework, final exam grades and satisfaction.

• Plant Biotechnology Reports
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• 제2권3호
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• pp.191-198
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• 2008

Germplasm characterization and evolutionary process in viable populations are important links between the conservation and utilization of plant genetic resources. Here, an investigation is made, based on molecular and biochemical techniques for assessing and exploiting the genetic variability in germplasm characterization of taro, which would be useful in plant breeding and ex situ conservation of taro plant genetic resources. Geographical differentiation and phylogenetic relationships of Indian taro, Colocasia esculenta (L.) Schott, were analyzed by random amplified polymorphic DNA (RAPD) and isozyme of seven enzyme systems with specific reference to the Muktakeshi accession, which has been to be proved resistant to taro leaf blight caused by P. colocasiae. The significant differentiations in Indian taro cultivars were clearly demonstrated by RAPD and isozyme analysis. RAPD markers showed higher values for genetic differentiation among taro cultivars and lower coefficient of variation than those obtained from isozymes. Genetic differentiation was evident in the taro accessions collected from different regions of India. It appears that when taro cultivation was introduced to a new area, only a small fraction of genetic variability in heterogeneous taro populations was transferred, possibly causing random differentiation among locally adapted taro populations. The selected primers will be useful for future genetic analysis and provide taro breeders with a genetic basis for selection of parents for crop improvement. Polymorphic markers identified in the DNA fingerprinting study will be useful for screening a segregating population, which is being generated in our laboratory aimed at developing a taro genetic linkage map.

• 천문학회보
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• 제37권1호
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• pp.77.2-77.2
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• 2012

Infrared dark clouds(IRDCs) are believed to be the progenitors of massive stars and clusters. We obtained 350 and 850 ${\mu}m$ continuum maps of the IRDC G049.40-00.01 using SHARC-II on CSO. Twenty-one dense clumps were identified within G049.40-00.01 based on the 350 ${\mu}m$ continuum map with an angular resolution of about 9.6". We present submillimeter continuum maps and report physical properties of the clumps. The masses of clumps are from 50 to 600 solar mass. About 70% of the clumps are associated with bright 24 ${\mu}m$ emission sources indicating protostars. The most massive two clumps show enhanced, extended 4.5 ${\mu}m$ emission representing on-going star forming activity. The size-mass distribution of the clumps suggests that many of them are forming high-mass stars. G049.40-00.01 contains numerous objects in various evolutionary stages of star formation, from pre-stellar clumps to H II regions.

• 한국시뮬레이션학회논문지
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• 제22권2호
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• pp.33-40
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• 2013

본 논문은 에이전트 기반 모델링 및 시뮬레이션을 바탕으로 한 한국군 GOP 경계시스템에 관한 연구이다. 에이전트 기반 모델링 및 시뮬레이션 기반 소프트웨어인 MANA를 이용하여 다양한 시나리오를 모델링하고 유전학적 알고리즘을 통해 침투 양상이 변화하는 적에 대해 분석하였다. 우리는 유전학적 알고리즘을 이용하여 침투하는 적의 최적화된 행동에 근사하는 값을 구하기 위해 최적화 모델을 구성하였다. 그 결과는 GOP 경계시스템에서 침투하는 적의 행동에 대한 최적화가 경계시스템의 효과성에 현저한 차이를 가져온다는 점과 침투하는 적의 아군 자산에 대한 회피 정도는 각각의 자산의 중요성을 반영한다는 점에서 두 가지 중요한 통찰력을 제공한다.

• 천문학회보
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• 제40권2호
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• pp.53.2-53.2
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• 2015

We present preliminary results from a series of observations toward G108.8-00.8, which is one of Planck Cold Clumps and a promising candidate of massive prestellar cores. In the integrated intensity map of SCUBA 850 micron dust continuum emission, highly fragmented structures appear. These are distributed along one long filamentary structure seen in the CO 1-0 and 13CO 1-0 integrated intensity maps obtained with the PMO 13.7 m telescope. The northern part of the filament is divided into two parts, as seen in the CO 2-1, 13CO 2-1, and C18O 2-1 integrated intensity maps obtained with the CSO 10 m telescope. The observations of HCO+ 1-0, N2H+ 1-0, and HCN 1-0 with the IRAM 30 m telescope focus on the northern part of the CSO maps, which show a head-tail structure. NH3 (1,1) also shows similar distribution with IRAM maps. The depletion factors, derived by the comparison between the dust continuum and C18O 2-1 emission, varies from 1.5 to 6 over the region, suggesting different evolutionary status of each component. To study the chemical and physical environments of G108.8-00.8, more detailed analysis is in progress.