이 논문에서는 고속철도교량 설계를 위한 활하중 모델을 통계 및 확률적 방법으로 검토하고, 하중조합의 하중계수가 주는 안전율을 분석하였다. 이 연구는 철도교량 설계기준에 대한 한계상태설계법 개발의 일환이며, 이를 위하여 경부고속철도를 운행하는 열차를 대상으로 약 한달 동안 실측하여 데이터를 수집하고 분석하였다. 이 데이터를 대상으로 교량의 설계수명에 맞도록 4가지 통계 방법들을 적용하여 설계하중을 추정하여 비교․검토하였다. 또한, 철도교량의 설계하중조합이 주는 안전율을 검토하기 위하여 신뢰도지수를 구하고 이를 분석하였다. 실측 데이터로부터 추정한 활하중효과에 대하여, 현행 고속철도 설계활하중인 표준열차하중의 0.75배를 적용한 설계활하중 효과의 크기가 최소 30～22% 더 크게 나왔다. 신뢰도분석을 통하여, 극한한계상태만을 기준으로 본다면, 추가적인 하중계수 감소의 가능성이 있음을 알 수 있다.

Foxglove aphid, Aulacorthum solani (Kaltenbach), is a Hemipteran insect that infected a wide variety of plants worldwide and caused serious yield losses in crops. The objective of this study was to identify the putative QTL for foxglove aphid resistance in wild soybean, PI 366121, (Glycine soja Sieb. and Zucc.). One hundred and forty one F2-derived F8 recombinant inbred lines developed from a cross of susceptible Williams 82 and resistant PI 366121, were used. The phenotyping of antibiosis and antixenosis was done through choice and no-choice assays with total plant damage (TPD) and primary infestation leaf damage (PLD); a genome-wide molecular linkage map was constructed with 504 single nucleotide polymorphism markers utilizing a GoldenGate assay. Using inclusive composite interval mapping analysis for foxglove aphid resistance, one major candidate QTL on chromosome 7 and 3 minor QTL regions on chromosome 3, 6 and 18 were identified. The major QTL on chromosome 7 showed both antixenosis and antibiosis resistance responses. However, the minor QTLs showed only antixenosis resistance response. The major QTL mapped to a different chromosome than the previously identified foxglove aphid resistance QTL, Raso1, from the cultivar Adams. Also, the responses to the Korea biotype foxglove aphid were different for Raso1, and the gene from PI 366121 against the Korea biotype foxglove aphid were different. Thus the foxglove aphid resistance gene from PI 366121 was determined to be an independent gene to Raso1 and designated to Raso2. This result could be useful in breeding for new foxglove aphid resistant soybean cultivars.

Foxglove aphid, Aulacorthum solani (Kaltenbach), is a Hemipteran insect that infected a wide variety of plants worldwide and caused serious yield losses in crops. The foxglove aphid resistance gene, Raso2 was previously mapped from PI 366121 (Glycine soja Sieb. and Zucc.) to a 26cM marker interval on soybean chromosome 7. The development of additional genetic markers, which are mapped closer to Raso2 were required to accurately position the gene to improve the effectiveness of marker assisted selection. The objective of this study was to narrow down the putative QTL region, which is responsible to foxglove aphid resistance in PI366121 using recently developed high-density 180K Axiom SoyaSNP genotyping array. One hundred and forty one F8-derived F12 recombinant inbred lines developed from a cross of susceptible Williams 82 and resistant PI 366121, were used to generate a fine map of Raso2 interval. The phenotyping of antibiosis and antixenosis was done through choice and no-choice assays with total plant damage (TPD) and primary infestation leaf damage (PLD). The composite interval mapping analysis showed that the physical interval between two flanking makers, which was corresponding to Raso2, was narrowed down to 500kb on the Williams 82 genome assembly (Glyma2.0), instead of 4Mb in the previous report using Goldengate assay. In the Raso2 interval, there are about 60 candidate genes, including 4 of NBS-containing putative R genes. This result could be useful in breeding for new foxglove aphid resistant soybean cultivars.

The depletion of stratospheric ozone has resulted in increased amount of ultraviolet-B radiation (UV-B: 280-320 nm) reaching the Earth’s surface and could cause significant biological effect in plants. In this study, putative quantitative trait loci (QTL), which is responsible to UV-B resistance in soybean, was identified using recently developed high-density 180K Axiom SoyaSNP genotyping array. A population of 115 recombinant inbred lines (RILs) derived from a cross between susceptible Keunolkong and resistant Iksan 10 was analyzed. A total 8,970 polymorphic SNP markers were used to construct linkage map. The both parents and RILs were grown with supplemental UV-B radiation in a greenhouse condition. Three categories of UV-B induced morphological damage, degree of leaf chlorosis, leaf shape change, and total plant damage were evaluated. Using composite interval mapping analysis, one major QTL associated with all of the phenotypic traits was detected on 7.7cM of soybean chromosome 7 with 22 of LOD score accounting for about 60% of phenotypic variance. Also, the allele from Iksan 10 were responsible for the UV-B resistance. Thus, the UV-B resistance QTL on chromosome 7 from Iksan 10 was designated to qUVBR1, corresponding to 30kb on the Williams 82 genome assembly (Glyma2.0) including 7 candidate genes. This result could be useful in breeding for new foxglove aphid resistant soybean cultivars. In addition, these results provided useful information not only for marker-assisted selection for UV-B resistance soybean, but also for the future identification of putative candidate genes, responsible for UV-B resistance in soybean.