수공구조물 설계시 실측 유량의 자료 부족으로 홍수량의 빈도해석 결과보다는 강우자료를 수집하여 강우-유출 관계에 따라 산정된 설계강우량을 이용하여 특정 빈도에 해당하는 설계 홍수량을 사용하는 것이 일반적이다. 과거에는 첨두유량 산정을 위하여 합리식과 같은 경험식을 이용하였으나 지속기간이 장기화됨에 따라 실제 사상과는 다른 유출양상이 나타나게 되므로 확률강우량 시간분포의 정확성이 중요하게 되었다. 현재 실무에서는 설계강우량의 시간분포 방법으로 Huff의 4분위 방법 중 3분위를 사용하고 있으며 분위별 곡선에 대한 회귀식은 지속기간 전반에 걸쳐 정확도가 높은 이유로 6차식을 적용하고 있다. 그러나 통계 모델링에서는 간결함의 원리에 따라 회귀식이 간결할 필요가 있으며, 통계적 유의수준에 기초하여 회귀계수를 결정할 필요가 있다. 따라서 본 연구에서는 기상청 관할 69개 강우관측지점을 대상으로 설계강우량의 시간분포 방법으로 사용되고 있는 Huff 4분위 방법의 시간분포 회귀식에 대한 유의성 검정을 실시하였다. 기상청 관할 69개 강우관측지점의 Huff 4분위 방법의 시간분포 회귀식의 유의성 검정결과 대부분의 지점에서 4차식까지 회귀계수가 유의한 것으로 나타나 통계학적으로 Huff의 4분위 방법의 시간분포 회귀식은 4차까지만 고려하여도 무방한 것으로 분석되었다.

The world population has been continuously increasing and has led to the growing demand for rice. It is therefore important to pay as much attention to the enhancement of grain yield as well as grain quality. Grain size is one of the major factors determining grain yield and quality. A large number of genes are known to be involved in regulation of grain size. However, the influence of their haplotype combination is still largely unknown. Of the previously characterized genes, we especially focused on the six genes (GS3, GS5, GS6, GW2, qSW5/GW5, and GW8/OsSPL16) to expand our understanding of regulation of grain size and to develop a regression equation model that can be used for molecular rice breeding. A total of 215 rice germplasms, which originated or developed from 28 rice-consuming countries, were used in this study. The genotyping analysis revealed that different alleles of the six genes were widely distributed in our germplasm collection and also showed significant associations with the differences in grain size. Interestingly, we found that the relatively small number of haplotype combinations preserved in diverse rice germplasms and showed significant associations with the differences in grain size. In addition, we also found that a single gene-specific allelic variation plays an important role in regulation of grain size in the presence of a certain type of haplotype combination. Based on these results, we developed a regression equation model for prediction of rice grain size. We expect that our model can be used for rice molecular breeding to develop new rice varieties having a grain size in a particular range.

The objective of this study is to suggest an equation of development length of GFRP rebar. A regression analysis was performed based on the experimental results failed by splitting failure. By regression analysis, this study can suggest to development length and it is possible to make more efficient design than the equations of ACI and JSCE.

The objective of this study is to evaluate Flow-Pollutant load delivery ratio equations developed from rural watershed on main subwatersheds within Juam Lake. Two regression equations for BOD and three equations for T-P were evaluated on Bosung cheon, Dongbok cheon, Songgwang cheon, Naenam cheon, and Sinpyeon cheon. The results show that estimation of BOD delivery ratio using flow-delivery equation is reliable when relative composition of discharge load of pollutant sources of a watershed is similar to those of watershed where the equation developed. On the other hand, application of regression equation for T-P was feasible when the landuse pattern and relative composition of discharge load of pollutant sources of a watershed is similar to those of watershed where the equation developed.