• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.341.2-341
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• 1995

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.1
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• pp.25-29
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• 2010

Thulium oxide-doped barium titanate ceramics for MLCCs with perovskite structure were prepared by a sintering process at $1320^{\circ}C$ for 2 h in a reduced atmosphere. The effect of $Tm_2O_3$ addition on dielectric property of barium titanate ceramics has been studied in terms of their microstructures. Moreover, the phase identification of the dielectric specimens was conducted to define the secondary phase (pyrochlore). The specimen doped with 1 mol% $Tm_2O_3$ exhibited the highest dielectric constant. However, the dielectric constants of specimens with more than 2 mol% $Tm_2O_3$ to $BaTiO_3$ were the lower values than that of 1 mol% doped one. The grain size and the formation of pyrochlore phase associated with the dielectric properties were examined through morphology development and the structural analysis. Furthermore, these data were compared with the property of the dielectric material doped with $Er_2O_3$. It could be concluded that the dielectric property of ceramic capacitors were attributed to the change of pyrochlore phase and the tetragonality of $BaTiO_3$ with doping.

• Journal of Science Education
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• v.40 no.3
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• pp.189-202
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• 2016

This study aimed to investigate pre-service science teachers' perceptions of significance and usefulness of evolution and genetics. To this end, 82 pre-service biology teachers and 159 non-biology science teachers answered the items to measure the perceptions of significance and usefulness of evolution and genetics. The validity and reliability were examined using Cronbach alpha, two-dimensional rating scale model Rasch analysis, and factor analysis. The finding illustrated that the test items met the benchmark to be valid and reliable test items. Second, pre-service teachers' perception of significance and usefulness of evolution was independent to that of genetics. The level of pre-service teachers' perception of significance and usefulness of evolution was lower than the level of genetics. Lastly, the levels of pre-service teachers' perceptions of significance and usefulness of evolution and genetics were not significantly different across academic years and majors (biology and non-biology). The findings of this study stressed the importance of teaching significance and usefulness of evolution and genetics in pre-service science teacher education program.

• Journal of Korea Water Resources Association
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• v.31 no.1
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• pp.59-69
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• 1998

A regression model with basin physiographic characteristics as independent variables was calibrated for regional flood frequency analysis. In case that high correlations existing among the independent variables the ridge regression has been known to have capability of overcoming the problems of multicollinearity. To optimize the ridge regression model the cost function including regularization parameter must be minimized. In this research the genetic algorithm was applied on this optimization problem. The genetic algorithm is a stochastic search method that mimic the metaphor of natural biological heredity. Using this method the regression model could have optimized and stable weights of variables.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2000.11a
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• pp.81-85
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• 2000

마이크로파대역에서 우수한 유전적 특성을 가지며 소결이 90$0^{\circ}C$ 이하에서 가능하여 Ag와 동시 소결이 가능한 유전체 조성을 개발하여 RF MCM-C(Multi-chip Module on Ceramic) 제조를 위한 유전체 테잎 제조에 대한 기초적인 실험과 Ag 전극과 동시소성에 대한 반응성 실험을 하였다. 본 실험에 앞서 개발된 유전체 조성의 마이크로대역에서의 유전특성은 유전율 24, 품질계수 30,000 이상, 공진주파수 온도계수 37 ppm/$^{\circ}C$ 이었고 소결온도는 85$0^{\circ}C$이었다. 이 유전체를 이용결함 없는 테잎 제조를 위한 유기용매의 선택, 바인더 및 가소제의 량 및 비에 따른 테잎의 소결 전 .후의 상태를 비교.분석하여 최적의 조성비를 결정하였다. 테잎과 은전극과의 반응성 실험결과 은과 유전체의 상호확산은 거의 이루어지지 않음을 확인하였다.

• Journal of Korean Society of Forest Science
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• v.106 no.4
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• pp.417-423
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• 2017

To provide a ecological restoration strategy considering genetic diversity of Abies koreana in Mt. Jiri, the genetic diversity and the genetic differentiation among sub-populations such as Banyabong, Byeoksoryeong, and Cheonwangbong were investigated. The average number of alleles (A) was 7.8, the average number of effective alleles ($A_e$) was 4.9, observed heterozygosity ($H_o$) was 0.578, and expected heterozygosity ($H_e$) was 0.672, respectively. The level of genetic diversity within sub-populations ($H_e=0.672$) was lower than those of both population ($H_e=0.778$) and species ($H_e=0.759$) level. However, the level of genetic diversity was high compared those of Genus Abies. Genetic differentiation was 0.014 from F-statistics ($F_{ST}$) and was 0.004 from AMOVA analysis (${\Phi}_{ST}$). There was no almost genetic differentiation among sub-populations in Mt. Jiri from bayesian clustering. Therefore, If the seeds are sampled sufficiently by selecting the parameters from three sub-populations, it is possible that we could obtain genetically appropriate materials for ecological restoration.

• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.560-569
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• 2011

In Japan, plant genomics research is mainly leaded by the national research institutes. The various structural studies such as rice genome has allowed researchers to analyze useful traits, and to focus their commercialization. With aims to facilitate structural and functional study in plant genome, NIAS (National Institute of Agrobiological Sciences) constructed Poaceae genome DB and RIKEN (Rikagaku Kenkyusho) built DB for Arabidopsis genome and plant full-length cDNA. NIG (National Institute of Genetics) constructed a national biological resources DB (National Bio Resource Project). This compiling DB provides a variety of genome-related research materials for researchers in the field. Recently, as an effort to resolve global issues of food supply and environmental problems, New Agri-genome Project has been performed aiming to develop an innovative agricultural technologies for the quantity, disease resistance and identifying useful genes related to environmental problems. In addition, in order to improve agricultural productivity in developing countries, JIRCAS assisted technical supports for the plant genome research and developed NERICA rice, which is suitable for African area. Such these approaches are expected to contribute to solving the global issues about food, energy and environment in the world.

• Korean Journal of Poultry Science
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• v.32 no.1
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• pp.29-34
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• 2005

This study was conducted to estimate the effects of genotype for chicken major histocompatibility complex (MHC) B-LB genes on economic traits. To detect polymorphism, 400 bp fragments of MHC B-LB genes were obtained and sequenced. After digestions using restriction enzyme Hea III, two restriction enzyme sites were observed. There were two mutations at position 427 and 651 those were decided as Type I and Type II, respectively. Using RFLP analyses, type I were genotyped to TT, TC and CC, and type II to MM, Mm and mm. The relatively higher TC genotype frequencies (0.8) of Type I and Mm genotype frequencies (0.88) of Type II were observed in Korean native chickens. The effects of the genotype on 150 days body weight trait were investigated by the associations of CC and Mm genotypes (P<0.05) in Korean native chickens. This result suggests that a significant association exists between the SNP and 150 days body weight.

• Korean Journal of Ecology and Environment
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• v.41 no.1
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• pp.98-103
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• 2008

Genetic diversity and population genetic structure within or among three stream populations (Gab, Baekgok and Ji streams) of Korean endangered natural monument fish, Iksookimia choii, were assessed by amplified fragment length polymorphism (AFLP). AFLP analysis using three primer combinations generated 104 to 106 AFLP bands, and percent polymorphic bands were similar in those three populations ranging 21.5 to 24.5%. Heterozygosity and genetic diversity within or among populations were quite low for all of these populations with average values ranging from 0.067 to 0.084 and from 0.076 to 0.087, respectively. Analyses of pairwise distance and genetic similarity among three populations of I. choii also revealed the similar results with very low genetic differentiation one another. Although pairwise Fst values were very low, our data clearly indicated distinct genetic differentiation among the three populations. This is the first report concerning the genetic diversity and differentiation of this species, and provides basic genetic information that should facilitate attempts to conserve this species.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.364-377
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• 2018

Hexaploid wheat (common wheat/bread wheat) is one of the most important cereal crops in the world and a model for research of an allopolyploid plant with a large, highly repetitive genome. In the heritability of agronomic traits, variation in gene presence/absence plays an important role. However, there have been relatively few studies on the variation in gene presence/absence in crop species, including common wheat. Recently, a reference genome sequence of common wheat has been fully annotated and published. In addition, advanced next-generation sequencing (NGS) technology provides high quality genome sequences with continually decreasing NGS prices, thereby dawning full-scale wheat functional genomic studies in other crops as well as common wheat, in spite of their large and complex genomes. In this review, we provide information about the available tools and methodologies for wheat functional genomics research supported by NGS technology. The use of the NGS and functional genomics technology is expected to be a powerful strategy to select elite lines for a number of germplasms.