• Journal of Korea Water Resources Association
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• v.56 no.12
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• pp.871-881
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• 2023

This study investigates the geomorphic changes and Bed Relief Index of the river downstream of the Yeongju Dam by Nays2DH, a two-dimensional numerical model, in order to grasp the dynamics of the downstream river while applying various flow patterns such as pulse discharge. It shows that the geomorphic and the bed elevations changes are the largest under the condition of the normalized pulse discharge. The total change in the riverbed is 29.88 m for uniform flow, 27.46 m for normalized hydrograph, 29.63 m for pulse flow and 31.87 m for pulse flow with normalized hydrograph which result in the largest variation in scour and deposition. The Bed Relief Index (BRI) increases with time under conditions of uniform flow, pulse flow and pulse flow with normalized hydrograph. However, BRI increased rapidly until 30 hrs after the peak flow (14 hrs), but decreased from 56 hrs under the condition of normalized hydrograph. Therefore, the condition of normalized hydrograph gives greater dynamics than the condition of a single flood or constant flow, and the dynamics increase downstream than upstream, resulting in an effect on improving the environment of the river downstream of the dam.

• Journal of Life Science
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• v.21 no.7
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• pp.969-975
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• 2011

We focused on relationship between phytohormones and AtEXPA3 gene in gravitropic response of A. thaliana. RT-PCR analysis shows that AtEXPA3 was highly expressed in actively developing tissues such as leaf, rosette, root and flower tissues. AtEXPA3 gene expression was enhanced by gravistimulation, BR and IAA. Furthermore, decreased gravitropism was observed when treatment of AVG, an ethylene biosynthetic inhibitor, suggesting that ethylene has a gravistimulating effect itself as well as BRs and IAA. Inhibition of gravitropism in AtEXPA3 RNAi mutant suggests that BR, auxin and ethylene are playing roles as regulators of AtEXPA3. In addition, altered gravitropism in BRs signaling mutant (decreased in bri1-301, bak1, and increased BRI-GFP) indicated that BRs signaling mediated the gravitropism. In conclusion, gravitropic responses of Arabidopsis root resulting from root growth were mediated by increased expression of AtEXPA3 gene, which is stimulated by phytohormones.

• SUVANNABHUMI
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• v.15 no.2
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• pp.57-90
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• 2023

China launched the Digital Silk Road (DSR) in 2015 as part of the existing Belt and Road Initiative (BRI) to expand its influence in digital and technological development across Asia, Europe, and Africa. Southeast Asia is one of the key targets of the Digital Silk Road due to its geographical proximity to China and the rapid growth of the digital sphere. Although the DSR opens several potential opportunities for the Association of Southeast Asian Nations (ASEAN) member states to foster the digitalization process in the region, how each country reacts to projects under the DSR is varied. Secondly, Vietnam is the only ASEAN member state that has not signed any official agreement under the BRI framework, and thirdly, Vietnam opted out of Huawei technology. This paper aims to understand the perspective of Vietnam and how Vietnam has responded to the growing technological presence of China in Southeast Asia until 2021. By using qualitative methods, the author argues that the DSR has allowed Beijing to overcome the limitations of the original strategy, BRI, and strengthen its influence in the field of information and communication technologies, particularly fifth-generation (5G) telecommunications. Furthermore, the paper examines Vietnam's digital development and digital diplomacy and how the Vietnamese government has responded to DSR projects. In light of both the potential threats and economic benefits that the DSR has brought to Vietnam and Southeast Asian countries, in the last section, the policy implications for cooperation are discussed.

• Research in Plant Disease
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• v.22 no.4
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• pp.289-292
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• 2016

We surveyed the occurrence of Japanese yam mosaic virus (JYMV) on Yam in Gyeongsangbukdo pronvince from 2013 to 2015. The symptoms of JYMV were yellow stripes and chlorosis in yam leaves and the infection rate was ranged from 33.6% to 40.8%. We determined nucleotide sequence encoding the polyprotein of JYMV isolate BRI from yam leaves using next-generation sequencing (NGS) method. The partial nucleotide portion (7,736 nucleotides) of the genomic RNA of the JYMV isolate BRI has been sequenced (accession No. KU309315). The region sequenced includes a single open reading frame (ORF) encoding a polyprotein composed of 2,497 amino acids containing the coat protein (CP) and 3' untranslated region (UTR). The genomic organization of this isolate shows almost the same to that of other members of JYMV. The JYMV isolate BRI showed 77% to 79% nucleotide identity with the Japanese and Chinese strains and isolates. This is the first report of the genome nucleotide sequence of JYMV from Dioscorea opposita in Korea.

• Computational Structural Engineering
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• v.15 no.1
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• pp.104-107
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• 2002

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.6B
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• pp.1068-1073
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• 1999

On the emergence of ISDN which has been introduced in the year 1980, various services are supported. This paper presents implementation of ISDN user/network protocol analyzer based on PC-extension card. Firmware and software are loaded on the PC-extension card using PC 05. The performance analysis on D-channel signalling on this system is surveyed. The monitoring results satisfiy with ISDN BRI or PRI interfaces.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.7
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• pp.956-961
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• 2014

Due to the increasing needs of anti-fall device for elderly, it is required to develop the test rigs for fall simulation. The femoral bone model consists of silicone and steel is used as an effective device to simulate falls. In this work, we propose five different femoral bone models and analyse them by using a commercial FEA tool. It has been shown that two kinds of simplified models exhibit the simulated side falls with an error range of ~1% in the impact load of femoral neck compared with full model. Especially, the upper tissue model is found to provide us with the best efficient test environment, attributable to its simple structure.

• Acta Via Serica
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• v.7 no.1
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• pp.83-104
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• 2022

This article attempts to explain current social perceptions in Mexico about the Silk Road. Based on a critical geopolitics approach, the author analyzes how the idea of the Silk Road is socially constructed in Mexican popular geopolitics, focusing on studying digital mass media between 2013 and 2020. The main research questions are: how is the Silk Road notion constructed in Mexican popular geopolitics and what are the geopolitical implications for Mexico? The article discovers that in Mexico, the idea of the "Silk Road" is profoundly close to the idea of the Belt and Road Initiative (BRI) given China's geostrategic discourse that constructs the BRI as a "New Silk Road". The article also argues that Mexico's social-political agency to deal with China may be hindered by divergent social perceptions in favor and against the "Silk Road".

• Journal of Korea Water Resources Association
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• v.54 no.8
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• pp.629-641
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• 2021

In this study, a two-dimensional numerical model (Nays2DH) was applied to analyze the process of morphological changes in the river channel bed depending on the changes in the amount of flooding after fully opening the Sejong weir, which was constructed upstream of the Geum River. For this, numerical simulations were performed by assuming the flow conditions, such as a non-uniform flow (NF), unsteady flows (single flood event, SF), and a continuous flood event (CF). Here, in the cases of the SF and CF, the normalized hydrograph was calculated from real flood events, and then the hydrograph was reconfigured by the peak flow discharge according to the scenario, and then it was employed as the flow discharge at the upstream boundary condition. In this study, to quantitatively evaluate the morphological changes, we analyzed the time changes in the bed deformation the bed relief index (BRI), and we compared the aerial photographs of the study area and the numerical simulation results. As simulation results of the NF, when the steady flow discharge increases, the ratio of lower width to depth decreases and the speed of bar migration increases. The BRI initially increases, but the amount of change decreased with time. In addition, when the steady flow discharge increases, the BRI increased. In the case of SF, the speed of bar migration decreased with the change of the flow discharge. In terms of the morphological response to the peak flood discharge, the time lag also indicated. In other words, in the SF, the change of channel bed indicates a phase lag with respect to the hydraulic condition. In the result of numerical simulation of CF, the speed of bar migration depending on the peak flood discharges decreased exponentially despite the repeated flood occurrences. In addition, as in the result of SF, the phase lag indicated, and the speed of bar migration decreased exponentially. The BRI increased with time changes, but the rate of increase in the BRI was modest despite the continuous peak flooding. Through this study, the morphological changes based on the hydrological characteristics of the river were analyzed numerically, and the methodology suggested that a quantitative prediction for the river bed change according to the flow characteristic can be applied to the field.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04a
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• pp.69-75
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• 2002

Sterols play two major roles in plants: a bulk component in biological membranes and precursors of plant steroid hormones. Physiological effects of plant steroids, brassinosteroids (BRs), include cell elongation, cell division, stress tolerance, and senescence acceleration. Arabidopsis mutants that carry genetic defects in BR biosynthesis or its signaling display characteristic phenotypes, such as short robust inflorescences, dark-green round leaves, and sterility. Currently there are more than 100 dwarf mutants representing 7 genetic loci in Arabidopsis. Mutants of 6 loci, dwf1/dim1/cbb1, cpd/dwf3, dwf4, dwf5, det2/dwf6, dwf7 are rescued by exogenous application of BRs, whereas bri1/dwf2 shares phenotypes with the above 6 loci but are resistant to BRs. These suggest that the 6 loci are defective in BR biosynthesis, and the one locus is in BR signaling. Biochemical analyses, such as intermediate feeding tests, examining the levels of endogenous BR, and molecular cloning of the genes revealed that dwf7, dwf5, and dwf1 are defective in the three consecutive steps of sterol biosynthesis, from episterol to campesterol via 5-dehydroepisterol. Similarly, det2/dwf6, dwf4, and cpd/dwf3 were shown to be blocked in $D^4$ reduction, 22a-hydroxylation, and 23 a-hydroxylation, respectively. A signaling mutant bri1/dwf2 carries mutations in a Leucine-rich repeat receptor kinase. Interestingly, the bri1 mutant was shown to accumulate significant amount of BRs, suggesting that signaling and biosynthesis are dynamically coupled in Arabidopsis. Thus It is likely that transgenic plants over-expressing the rate-limiting step enzyme DWF4 as well as blocking its use by BRI1 could dramatically increase the biosynthetic yield of BRs. When applied industrially, BRs will boost new sector of plant biotechnology because of its potential use as a precursor of human steroid hormones, a novel lead compound for cholesterol-lowering effects, and a various application in plant protection.