• Molecules and Cells
• /
• v.20 no.2
• /
• pp.210-218
• /
• 2005

The rice genome contains at least 28 EXPA (${\alpha}$-expansin) genes. We have obtained near full-length cDNAs from the previously uncharacterized genes. Analysis of these newly identified clones together with the 12 identified earlier showed that the EXPA genes contain up to two introns and encode proteins of 240 to 291 amino acid residues. The EXPA proteins contain three conserved motifs: eight cysteine residues at the N-terminus, four tryptophan residues at the C-terminus, and a histidine-phenylalanine-aspartate motif in the central region. EXPA proteins could be divided into six groups based on their sequence similarity. Most were strongly induced in two-day-old seedlings and in the roots of one-week-old plants. However, only 14 genes were expressed in the aboveground organs, and their patterns were quite diverse. Transcript levels of EXPA7, 14, 15, 18, 21, and 29 were greater in stems, while EXPA2, 4, 5, 6, and 16 were highly expressed in both stem and sheath but not in leaf blade. EXPA1 is leaf blade-preferential, and EXP9 is leaf sheath-preferential. Most of the root-expressed genes were more strongly expressed in the dividing zone. However, the Group 2 EXPA genes were also strongly expressed in both mature and dividing zones, while EXPA9 was preferentially expressed in the elongation zone. Fourteen EXPA genes were expressed in developing panicles, with some being expressed during most developmental stages, others only as the panicles matured. These diverse expression patterns of EXPA genes suggest that in general they have distinct roles in plant growth and development.

• Geophysics and Geophysical Exploration
• /
• v.24 no.3
• /
• pp.78-88
• /
• 2021

Owing to the abnormal weather conditions due to global warming, carbon capture and storage (CCS) technology has attracted global attention as a countermeasure to reduce CO₂ emissions. In the Pohang CCS demonstration project in South Korea, 100 tons of CO₂ were successfully injected into the subsurface CO₂ storage in early 2017. However, after the 2017 Pohang earthquake, the Pohang CCS demonstration project was suspended due to an increase in social concerns about the safety of the CCS project. In this study, to reconfirm the structural suitability of the CO₂ storage site in the Pohang Basin, we employed seismic imaging based on reverse-time migration (RTM) to analyze small-scale ocean-bottom seismic data, which have not been utilized in previous studies. Compared with seismic images using marine streamer data, the continuity of subsurface layers in the RTM image using the ocean-bottom seismic data is improved. Based on the obtained subsurface image, we discuss the structural suitability of the Pohang CO₂ storage site.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
• /
• 2002.11a
• /
• pp.322-325
• /
• 2002

제약적인 권한 위임은 분산 환경에서 작업을 처리하기 위해서 필요한 권한을 부여하는 중요한 과정이다. 하지만 기존 그리드 환경의 아키텍처에서는 작업에 따른 적절한 권한을 부여하지 못하고, 부여한 권한의 오용을 막을 수 없는 등의 문제들이 있다. 본 연구에서는 그리드 환경에서 작업 시나리오에 기반한 제약적 권한 위임을 제안한다. 제안한 기법은 인증서에 작업 시나리오를 유지하여 관리하고, 유일한 식별자로 작업을 구분하는 것으로 기존의 문제점을 해결한다.

• Journal of the Korean earth science society
• /
• v.26 no.2
• /
• pp.166-171
• /
• 2005

Fossil legumes of Albizia miokalkora Hu et Chaney (Mimosoideae) were found in the Miocene Duho Formation of the Yeonil Group distributed along the coast of Yeonil Bay in the Pohang area. The legume is flat and long and has 5-7 rounded seeds. The legumes of Albizia miokalkora are rare in the Cenozoic floras of the world and only known to Middle Miocene of East Asia. The fossil Albizia may use one of the important taxa to construct the biogeographic history of East Asia. This discovery is the first record of Albizia from the Neogene strata of Korea.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2005.02a
• /
• pp.58-58
• /
• 2005

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.81-82
• /
• 2006

In this study, the applications of the block copolymer thin films are introduced. For this purpose, we first obtained cylindrical nanodomains in polystyrene-block-poly(methyl methacrylate) copolymer perpendicularly oriented to a substrate. Then, nanoporous templates were prepared after removing the PMMA nanodomains by UV treatment. By using electropolymerization, high density nanowire arrays of conducting polymer of poly(pyrrole) and poly( 3-hexyl thiopene) were obtained and their electric properties were measured. Also, these nanoporous thin films were found to be very useful for the separation of human Rhinovirus type 14 (HRV 14), major pathogen of a common cold in humans, from the buffer solution.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.251-251
• /
• 2006

A real time bio-imaging of HA degradation was successfully carried out using HA-quantum dot conjugates. HA-ADH with ADH content of ca. 70 mol% was synthesized and conjugated with quantum dots containing carboxyl terminal ligands which were activated by the addition of HOBt and EDC in DMSO. When the concentration of HA-ADH solution was higher than 4 wt%, HA-ADH hydrogels incorporating quantum dots could be synthesized in 30 minutes. These novel HA-quantum dot conjugates and the precursor solution of HA hydrogels incorporating quantum dots were injected to the nude mouse and investigated to elucidate the biological roles of HA in the body for various future tissue engineering applications.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.271-271
• /
• 2006

The present article describes a novel method of preparing the sulfonated polysulfone-based PEMs for DMFC, which are excellent in film quality, proton conductivity, methanol impermeability and mechanical properties. No depression in film quality or difficulty in film preparation is observed, even though sulfonated group of the PEMs are kept as high as 70 mol %. Allyl-terminated cooligo-PESs containing the organic sulfonate groups were solvent-cast into films and then thermally treated for cross-linking. Cross-linked sulfonated polysulfone-based PEMs gave unprecedented reduction of methanol cross-over and high ionic conductivity through in-situ thermal polymerization and cross-linking of telechelic sulfonated sulfone oligomers during a membrane preparation.

• Journal of the Korea Computer Graphics Society
• /
• v.11 no.2
• /
• pp.47-55
• /
• 2005

곡면 복원이나 곡면 복원과 질은 관련이 있는 노말 추정을 하는 대부분의 방법은 결정론적인 알고리즘을 사용한다. 결정론적 알고리즘은 속도가 빠르고, 오차가 크지 않은 입력에 대해서는 좋은 질의 곡면 복원을 할 수 있다. 그러나 결정론적 방법의 특성상 이상치나 노이즈를 가진 데이터에 대해서는 안정된 복원 결과를 얻을 수 없다. 본 논문에서는 앙상블이라고 불리는 통계적인 방법을 사용해서 곡면 복원과 노말 추정을 하는 기존의 알고리즘을 개선한다. 앙상블 기법은 먼저 입력 점 집합을 무작위로 샘플링해서 점 집합의 부분집합을 만든다. 그리고 나서 만들어진 부분 집합에 독립적으로 결정론적인 알고리즘을 적용하여 결과를 얻어낸다. 마지막으로, 각각의 서로 다른 결과를 결합하여 더 우수한 최종결과를 얻어낸다. 널리 쓰이는 노말 추정 기법[11]과 Multi-level Partitions of Unity implicit [18]를 사용해서 앙상블이 효과적으로 노이즈가 많은 데이터를 처리할 수 있는 것을 보여준다.

• Proceedings of the Korean Environmental Sciences Society Conference
• /
• 2003.11a
• /
• pp.59-60
• /
• 2003

In this study, we present the analysis of vertical ozone sounding data observed over Pohang, Korea, and investigate to understand the governing mechanisms for seasonal ozone maximum in June. The vertical ozone profiles in June show that the ozone enhancement is clearly shown in the middle and upper troposphere. We have found that the June maximum is associated with the transport of ozone rich air from the stratosphere and polluted continental air mass. This is different from the previous studies shown that the regionally polluted continental air mass, influenced by the intense anthropogenic activities m northeast Asia during transport, is responsible for the ozone maximum in spring.