• Korean Journal of Plant Taxonomy
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• v.31 no.4
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• pp.343-358
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• 2001

We have examined the pedicel pubescence and other major morphological characters of 11 putative hybrid populations of Aconitum subgn. Aconitum at Mt. Sobaek to understand their origin. These populations show very complicated patterns of variation in pedicel pubescence ; they contain individuals having pedicels (1) completely glabrous, (2) with few micropapillate curved hairs near the receptacle, (3) moderately pubescent with micropapillate curved hairs from middle to upper portion, (4) sparsely pubescent with a mixture of micropapillate curved hairs and smooth-surfaced spreading glandular hairs near the receptacle, and (5) moderately pubescent with both types of hairs but from middle to upper portion. All five types of individuals co-occur in most populations with varying proportions. These results, in conjunction with evidence from the analysis of other major morphological characters, suggest that the populations at Mt. Sobaek were derived from the multiple hybridization events involving A. kusnezoffii, A. japonicum subsup. napiforme, and A. jaluense subsp. jaluense. In addition, the absence of "typical" forms of these putative parental taxa in Mt. Sobaek area suggests that repeated introgression has probably occurred in these populations.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.77-83
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• 2014

To improve the breeding efficiency of oriental pear, the inheritance of major fruit traits were analyzed using 4,035 seedlings of 15 cross combinations combined with 13 cultivars. Yearly variation of parental cultivars, broad-sense heritability of the traits, and frequency of seedlings with commercially acceptable characteristics by the mid-parent values were studied. Despite the heritabilities of traits related with pear the fruit texture were different depending on cross combination, the average narrow-sense heritability ($h^2$) for firmness, flesh hardness, flesh density and grit were over 0.6, a relatively high value. However fruit firmness showed different heritability among the cross combination and its value of cross combination between 'Niitaka' and 'Choju' was very low as 0.11. Positive correlation was not observed on fresh hardness, fresh density and grit but observed on firmness between mid-parent value and average value of offspring. Regression of offspring on firmness, fresh hardness, fresh density and grit between mid-parent value and average value of offspring were 0.778, 0.343, -0.273, 0.313, respectively. Frequency distributions of fruit texture in 15 cross combinations of pear seedling was influenced by parental characteristics. When fruit firmness was estimated as low, low ${\times}$ high and high ${\times}$ high values in parental fruits, firmness in their offspring exhibited low, medium and high, respectively. In addition, when parental grit by sensory evaluation were light ${\times}$ light and light-medium ${\times}$ medium-heavy, most of offsprings showed light and medium grit, respectively.

• Journal of the Economic Geographical Society of Korea
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• v.14 no.3
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• pp.377-393
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• 2011

This study aims to indicate the spatial characteristics of the changes in the Korean farm land. In particular, we analyze the spatial diffusion patterns of organic farms increasing rapidly with the growth in the agricultural product markets as well as the demand for safe food and sustainable growth. For the purpose, we examine the changes in the distribution patterns of organic farms between year 2000 and 2005. We analyze the agglomeration pattern by Location Quotient (LQ) and Local indicator of spatial association (LISA). Organic farms have been spread out from the outscuirts of Seoul, the capital city, to the traditional agriculture spetilized area in the southern parts of the nation. In order to analyze the relationships between organic farm distribution and the geographical variables affecting the organic farming, we develop multivariate regression models. Our findings indicate that organic farming is related with the number of agriculture-based business and information technique adaptation as well as the level of education and farmers age.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.4
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• pp.613-630
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• 2013

This study attempts to analyze the spatial characteristics of organic agriculture in Korea during the period of 2000~2010, focusing on women's labor contribution to agricultural operations. Spatial distribution and concentration of organic farming have been investigated using Location Quotient(LQ) and Local Indicator of Spatial Association(LISA), it was found that the specialized organic farmland in the Seoul Metropolitan area has decreased significantly over the past decade, while in Chungnam and Kyungpook province it has been rapid growth in the same period. Multilinear regression analysis was also carried out to find out whether the spatial clusters in organic farming depends on women farmers. Results describing the correlation between organic farming and women farmers within identified clusters suggest that the possibility of the transition towards sustainable agriculture and farmland restructuring in Korea, by women.

• Korean Journal of Medicinal Crop Science
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• v.9 no.1
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• pp.76-82
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• 2001

This study was conducted to find out the optimum ranges of soil physical properties for wasabi growth by the relationship of soil physical properties and plant growth. Soil bulk density and hardness were higher in decomposition of granite and river sand than hydroball. This root distribution of surface layer was higher in decomposition of granite and river sand than hydroball. Growth characteristics and yield were higher in hydroball than decomposition of granite and river sand. In inlet site, the marketable rhizome weight in decompasition of granite, river sand, hydroball were 298kg/10a, 401kg/10a, 766kg/10a, respectively. But outlet, the weight in three soils were 251kg/10a, 256kg/10a, 633kg/10a, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.87-90
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• 2011

본 논문에서는 유전자 알고리즘에 SOM 알고리즘을 적용하여 효율적으로 경로를 탐색할 수 있는 방법을 제안한다. 제안된 경로 탐색 방법은 효율적인 경로 탐색에 앞서 유전자 알고리즘에 의해 도출된 각각의 결과 좌표를 뉴런으로 설정하고 각 뉴런들의 모든 거리 값을 SOM 알고리즘에 적용하여 거리에 대한 가중치를 구한다. 뉴런 선택 조건(가장 적은 거리 가중치, 이전에 선택되지 않았던 뉴런)을 만족하는 뉴런 및 해당 뉴런의 이웃 반경 내에 존재하는 뉴런들의 연결 강도를 가우시안 분포(오차율 분포)에 적용하여 변경하고, 가장 강한 연결 강도를 가지는 승자 뉴런에 해당하는 경로를 선택한다. 이러한 과정을 뉴런의 개수만큼 반복하여 모든 뉴런들의 경로를 도출한다. 제안된 방법을 실험한 결과, 기존의 유전자 알고리즘을 이용한 방법보다 제안된 방법이 효율적인 경로를 탐색하는 것을 확인할 수 있었다.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.970-973
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• 2011

유색 금 합금 중의 하나인 퍼플골드(purple gold)는 특유의 적자색(보라색)이 나는 78wt%Au-22wt%Al의 조성으로 이루어진 금 합금으로 많은 각광을 받고 있다. 본 연구에서는 78wt%Au-22wt%Al(이후 Au1)인 기준 조건보다 Al의 상대조성이 커짐에 따라 보라색과 기계적 물성의 변화를 확인하기 위해 76wt%Au-24wt%Al(이후Au2), 74wt%Au-26wt%Al(이후 Au3), 72wt%Au-28wt%Al(이후 Au4)으로 Al 조성을 22~26%Al까지 변화시키고 이때의 비커스 경도, 광학현미경, EDS, UV-VIS-NIR 색차분석 실험을 실시하였다. 비커스경도 측정결과 Al의 함유량이 증가함에 따라 경도값은 감소하는 경향성을 보였으며, 26wt%Al 이상의 조성에서 Au1 조성에 상응하는 경도 값을 유지할 수 있음을 확인하였다. 광학현미경을 이용한 미세구조 분석결과 Al의 함유량이 증가함에 따라 적자색을 띄는 결정립 $AuAl_2$의 분포는 감소하며, 결정립계에 석출하는 Al-rich 상의 분포와 크기는 증가하는 경향을 확인하였다. EDS를 이용한 성분분석 결과 실제 목표했던 조성과 분석오차를 고려하면 잘 일치함을 확인하였다. UV-VIS-NIR를 이용한 색차 분석결과 Au3 조성까지도 보라색을 유지할 수 있음을 확인하였다. 따라서 비커스경도와 색을 고려하면 기존 19K인 Au1보다 18K의 Au2 조성에서도 퍼플골드 구현이 가능하였다. 이후 Au2 조성으로 블랙홀과 아라크네를 모티브로 하여 실제 주얼리 제품을 성공적으로 제조하였다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.9
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• pp.901-907
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• 2015

The Vickers hardness test is a common method used to characterize the hardness of ceramic materials. However, the hardness is not a deterministic value, but is a random variable. The objective of this paper is to investigate the statistical properties of the bending strength and a set of Vickers hardness values in single $ZrO_2$ and composite $ZrO_2/SiC$ with a SiC additive. In this work, we compare the characteristic value and variation with the results based on Weibull statistical analysis. The probability distributions of the bending strength and Vickers hardness agreed relatively well with the Weibull distribution. We evaluate the scale parameter and shape parameter in asreceived $ZrO_2$ and $ZrO_2/SiC$ composite ceramics, as well as in their heat treated ceramics.

• Applied Biological Chemistry
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• v.42 no.1
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• pp.45-48
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• 1999

Rice was ground on a blade-type food mixer and sieved on meshes. The throughs on 60 and 80 mesh sieves were significantly different among maturity groups. The hardness of rice grain was negatively correlated with throughs on 60 and 80 mesh sieves and positively correlated with overs on 20 mesh sieve. The amylograph peak viscosity was increased as the particles became finer, but peak viscosities of the throughs on 60 and 80 mesh sieves were not significantly different.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2011.05a
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• pp.193-195
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• 2011

강판재 사용에 있어 수소취성현상은 강판재가 고강도화됨에 따라 그 감수성이 커지는 것으로 알려져 있다. 특히 노출강판재의 경우, 표면으로부터 침투해 들어가는 수소에 의한 수소취화 거동에 대한 연구가 필요하다. 본 연구에서는 고강도 DP강을 시험편으로 하여, 음극전기분해법에 의해 수소를 강제주입시킨 후, DP강 표면하 subsurface zone의 수소취화 거동을 평가하고자 하였다. 미소경도분포 측정결과, 수소주입시간이 증가함에 따라 표면하 subsurface zone의 경도 또한 증가하는 것으로 조사되었다. 이는 수소에 의해 표면하 subsurface zone의 경화가 일어나 DP강의 기계적 특성에 영향을 미친것으로 판단된다. 미소경도분포의 측정결과와 미세조직 관찰결과로부터 수소임계침투깊이를 평가하였고, 이를 통해 DP강내 수소확산에 의한 수소임계침투깊이가 존재함을 확인할 수 있었다.