Structures of domestic nuclear power plants are designed to perform elastic behavior against beyond design earthquakes, but studies on the nonlinear behavior of structures have been insufficient since the beyond design earthquake. Accordingly, it is judged that it will be necessary to develop an evaluation method that considers the nonlinear behavioral characteristics to check the safety margin for a standard nuclear power plant structure. It is confirmed that the restoring force characteristics for each member level can be identified through the calculation formula, and the lateral stiffness for each story can also be easily calculated by JEAC 4601. In addition, as a result of applying the evaluation method of JEAC 4601 as a nonlinear restoring force model of the nuclear power plant, a certain degree of safety margin can be identified.

Drought is one of important environmental stress for plant. Drought has deleterious effect to plant growth including maize (Zea mays L.) such as vegetative and/or reproductive growth, root extension, photosynthesis efficiency, flowering, anthesis-silking interval (ASI), fertilization, and grain filling. In this study, we screened drought tolerant maize in 21 cultivars from different sources, sixteen NAM parent lines (B73, CML103, CML228, CML247, CML277, CML322, CML333, CML69, Ki11, Ki3, Ky21, M37W, Mo18w, NC350, Oh43 and Tx303), four Korean hybrids (Cheongdaok, Gangdaok, Kwangpyeongok and Pyeonganok) and one Southeast Asian genotype (DK9955). Drought stress (DS) index was evaluated with leaf rolling score at seedling stage and ASI at silking date. The leaf rolling scoring of CML228, DK9955 and Ki11 were determined 1.28, 1.85, 1.86, respectively. However, M37W, Kwangpyeongok, B73 and NC350 were determined over the 3. ASI analysis revealed that CML228, CML103, Cheongdaok, NC350, B73, CML322, Kwangpyeongok and Ki11 are represented less than 5 days under DS and less than 3 days of difference between DS and well-watered (WW), but CML69, Ki3, Pyeonganok, M37W, Mo18w and Gangdaok were represented more than 10 days under DS and more than 8 days of difference between DS and WW. Multi-Dimensional Scaling (MDS) analysis determined CML228, Ki11, and CML322 were regarded as drought tolerance cultivars. Eventually, Ki11 showed genetic similarity with Korean cultivars by QTL analysis and MDS analysis. Ki11 has a potential for development of drought tolerance maize with Korean cultivars.

유라시아의 지역 내 인프라 연결과 협력에 관하여 많은 국가들이 다양한 정책을 추진하고 있는 가운데 중국은 일대일로 사업 을 제시했으며, 60여 개국 이상이 사업에 참여하면서 중국은 유라시아 물류 인프라 개발에서 매우 큰 영향력을 행사하게 될 것으로 예상되 고 있다. 본 연구는 사회네트워크 방법론을 통해 주요 철도역에 대한 네트워크를 분석했다. 유라시아 대륙의 대표적 철도노선인 TAR, TEN-T, TRACECA, GMS 경로를 통해 65개 국가, 994개 철도역에 대한 네트워크를 구성했으며, SNA의 측면에서 주요 철도역에 대한 특 징을 제시하고, 중국과 전체 유라시아 네트워크를 비교했다. 유라시아 및 중국 네트워크에 대한 분석을 통해 연결중심성과 매개중심성에서 각각 상위 30개 역을 제시했으며, 연결성 측면에서 태국 방콕, 조지아의 트빌리시, 아제르바이젠의 바쿠, 중국의 쿤밍, 루마니아의 부쿠레슈 티 등이, 매개성 측면에서 아제르바이젠의 바쿠, 알야트, 중국의 바오지, 투르판, 우즈베키스탄의 카르시, 터키의 카스 등이 높은 순위를 보 였다. 또한, 중국 네트워크에서는 쿤밍, 난닝, 거쥬역의 연결성과 바오지, 쿤밍, 란저우역 등의 매개성이 높게 도출되었다. 중국에서 추진하 는 일대일로 사업은 유라시아 전체의 인프라 연결 확충을 기본 전제로 하고 있지만, 중국과의 연계성 강화를 위한 인프라 개발에 높은 비 중이 예상되며, 이런 관점에서 국제 물류 거점에 대한 연구는 중국 네트워크에서 차지하는 중요성을 병행해서 검토할 필요가 있다.

This study was conducted to evaluate maize downy mildew resistance using spreader row technique in Cambodia. A total of forty maize lines were used in this experiment. Seven Korean varieties and seven breeding lines showed high infection rates (80~100%) and highly susceptible (HS) to downy mildew disease in both spring and fall. Also most of nested association mapping (NAM) parent lines were highly susceptible (HS). Meanwhile three inbred lines, Ki3, Ki11, and CML228, showed highly resistant (HR) or resistant (R) in spring and moderately resistant (MR) in fall. These three lines were already known as resistant inbred lines against downy mildew disease. It appears that spreader row technique was suitable for selection of maize downy mildew resistance in Cambodia. The incidence of downy mildew was influenced by weather conditions, especially relative humidity and temperature. Among several inoculation methods to screen for downy mildew resistance, this spreader row technique is effectively and easily used in the field of Southeast Asia.

The objective of this study was to evaluate the drought tolerance in maize seedling using leaf rolling. Nineteen maize resources, seven Nested Association Mapping parents lines, six Korean commercial cultivars, and six Southeast Asia commercial cultivars, were used to examine drought tolerance. The leaf rolling scores were measured on each leaf in three stress conditions with moderate drought (10%), severe drought (7%), and extreme drought (5%). Generally leaf rolling score of seedlings increased at the lower soil water potentials (5~7%). As a result, drought-tolerant cultivars showed lower leaf rolling score (below 2.5) than the drought sensitive cultivars (above 3.5). Nine varieties, NK4043, CML322, DK9955, NK4300, Ki11, DK8868, CML228, LVN99, and LVN10, have been selected for tolerance to drought stress. These results suggest that the leaf rolling score in maize seedling has been made available to indirect index for drought tolerance.

The photochemical characteristics were analyzed in the context of sowing time and different levels of fertilized nitrogen during the maize (Zea mays L.) growth. When maize was early sawn, the fluorescence parameters related with electrontransport, in photosystem II (PSII) and PSI, were effectively enhanced with the higher level of fertilized nitrogen. Highest values were observed in maize leaves grown in double Nfertilized plot. The photochemical parameters were declined in the progress of growth stage. In early growth stage, the fluorescence parameters were highest, and then reduced to about half of the parameters related with electron transport on PSII and PSI at middle and late growth stages. In 1/2 N plot, the photochemical energy dissipation was measured to 13% in term of active reaction center per absorbed photon resulting in decrease in performance index and driving force of electron. This decrease induced to lower the photochemical effectiveness. In 2 N plots, the electron transport flux from QA to QB per cross section and the number of active PSII RCs per cross section were considerably enhanced. It was clearly indicated that the connectivity between photosynthetic PSII and PSI, i.e. electron transport, was far effective.

Transcription factors are essential for the regulation of gene expression in plant. They are binding to either enhancer or promoter region of DNA adjacent to the gene and are related to basal transcription regulation, differential enhancement of transcription, development, response to intercellular signals or environment, and cell cycle control. The mechanism in controlling gene expression of transcription can be understood through the assessment of the complete sequence for the maize genome. It is possible that the maize genome encodes 4,000 or more transcription factors because it has undergone whole duplication in the past. Previously, several transcription factors of maize have been characterized. In this review article, the transcription factors were selected using Pfam database, including many family members in comparison with other family and listed as follows: ABI3 / VP1, AP2/EREBP, ARF, ARID, AS2, Aux/IAA, BES1, bHLH, bZIP, C2C2-CO-like, C2C2-Dof, C2C2-GATA, C2C2- YABBY, C2H2, E2F/DP, FHA, GARP-ARR-B, GeBP, GRAS, HMG, HSF, MADS, MYB, MYB-related, NAC, PHD, and WRKY family. For analyzing motifs, each amino acid sequence has been aligned with ClustalW and the conserved sequence was shown by sequence logo. This review article will contribute to further study of molecular biological analysis and breeding using the transcription factor of maize as a strategy for selecting target gene.

Maize is one of the most important food and feed crops in the world including Southeast Asia. In spite of numberous efforts with conventional breeding, the maize productions remain low and the loss of yields by drought and downy mildew are still severe in Asia. Genetic improvement of maize has been performed with molecular marker and genetic engineering. Because maize is one of the most widely studied crop for its own genome and has tremendous diversity and variant, maize is considered as a forefront crop in development and estimation of molecular markers for agricultural useful trait in genetics and breeding. Using QTL (Quantitative Trait Loci) and MAS (Marker Assisted Breeding), molecular breeders are able to accelerate the development of drought tolerance or downy mildew resistance maize genotype. The present paper overviews QTL/MAS approaches towards improvement of maize production against drought and downy mildew. We also discuss here the trends and importance of molecular marker and mapping population in maize breeding.