• 한국생태학회:학술대회논문집
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• 2002.08a
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• pp.71-77
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• 2002

For landscape ecological management of the isolated forestlands in Incheon city located in the western tip of South Korea, the forest vegetation of Mt. Cheolma was classified phytosciologically and mapped out its spatial distribution at a scale of 1:5,000. Characteristics of forest landscape structures were discussed in terms of the number and size of patches obtained by analyzing vegetation map. Units to manage the forest vegetation were categorized into eighteen communities, seventeen groups, and sixteen subgroups. Landscape elements were classified into five types: secondary vegetation, introduced vegetation for forestry (IVF), introduced vegetation for agriculture (IVA), and other elements. Two hundred and ninety-three forest landscape patches covers 443.3ha of which IVF accounted for 316.8ha(71.5%), the largest portion, secondary vegetation for f01.2ha(22.8%), IVA for 6.2ha(1.4%), and others for 19.1ha(4.3%). The ratio of natural forest elements of 31.9% showed that this area was mainly comprised of artificially introduced vegetation, such as Robinia pseudoacacia plantation and Pinus rigida plantation. Forest landscape patches have a mean area of 4.5ha, a density of 66.1/100ha, and a diversity index of 0.87. It was estimated that differentiation of patches recognized in community level would be related to human interference and those in subordinate level to natural processes.

• BMB Reports
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• v.50 no.10
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• pp.485-486
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• 2017

Many intrinsically unstructured/unfolded proteins (IUPs) contain transient local secondary structures even though they are "unstructured" in a tertiary sense. These local secondary structures are named "pre-structured motifs (PreSMos)" and in fact are the specificity determinants for IUP-target binding, i.e., the active sites in IUPs. Using high-resolution NMR we have delineated a PreSMo active site in the intrinsically unfolded mid-domain (residues 201-300) of SUMO-specific protease 4 (SUSP4). This 29-residue motif which we termed a p53 rescue motif can protect p53 from mdm2 quenching by binding to the p53-helix binding pocket in mdm2(3-109). Our work demonstrates that the PreSMo approach is quite effective in providing a structural rationale for interactions of p53-mdm2-SUSP4 and opens a novel avenue for designing mdm2-inhibiting anticancer compounds.

• Korean Journal of Materials Research
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• v.10 no.11
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• pp.743-748
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• 2000

Amorphous carbons(neddle cokes), which are used as anode materials for lithium ion secondary batteries, were graphitized or heat-treated at high temperature in $N_2$ atmosphere and in Ar atmosphere, after adding $B_2O_3$. After then, using transmission eletron microscopy, their surface micro-structures and the formations and distributions of the second phases were analyzed. It was studied that such analyzed results were related to the cell capacities and efficiencies.

• The Korean Journal of Ecology
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• v.25 no.4
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• pp.205-211
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• 2002

For landscape ecological management of the isolated forestlands in Incheon city located in the western tip of South Korea, the forest vegetation of Mt. Cheolma was classified phytosciologically and mapped out its spatial distribution at a scale of 1:5,000. Characteristics of forest landscape structures were discussed in terms of the number and size of patches obtained by analy zing vegetation map. Units to manage the forest vegetation were categorized into eighteen communities, seventeen groups, and sixteen subgroups. Landscape elements were classified into five types: secondary vegetation, introduced vegetation for forestry (IVF), introduced vegetation for agriculture (IVA), and other elements. Two hundred and ninety-three forest landscape patches covers 443.3ha, of which IVF accounted for 316.8ha(71.5$\%$), the largest portion, secondary vegetation for 101.2ha(22.8$\%$), IVA for 6.2ha(1.4$\%$), and others for 19.1ha(4.3$\%$). The ratio of natural forest elements of 31.9$\%$ showed that this area was mainly comprised of artificially introduced vegetation, such as Robinia pseudoacacia plantation and Pinus rigida plantation. Forest landscape patches have a mean area of 4.5ha, a density of 66.1/100ha, and a diversity index of 0.87. It was estimated that differentiation of patches recognized in community level would be related to human interference and those in subordinate level to natural processes.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.1
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• pp.99-110
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• 2022

In decommissioning a nuclear power plant, numerous concrete structures need to be demolished and decontaminated. Although concrete decontamination technologies have been developed globally, concrete cutting remains problematic due to the secondary waste production and dispersion risk from concrete scabbling. To minimize workers' radiation exposure and secondary waste in dismantling and decontaminating concrete structures, the following conceptual designs were developed. A micro-blast type scabbling technology using explosive materials and a multi-dimensional contamination measurement and artificial intelligence (AI) mapping technology capable of identifying the contamination status of concrete surfaces. Trials revealed that this technology has several merits, including nuclide identification of more than 5 nuclides, radioactivity measurement capability of 0.1-10⁷ Bq·g^-1, 1.5 kg robot weight for easy handling, 10 cm robot self-running capability, 100% detonator performance, decontamination factor (DF) of 100 and 8,000 cm²·hr^-1 decontamination speed, better than that of TWI (7,500 cm²·hr^-1). Hence, the micro-blast type scabbling technology is a suitable method for concrete decontamination. As the Korean explosives industry is well developed and robot and mapping systems are supported by government research and development, this scabbling technology can efficiently aid the Korean decommissioning industry.

• ALGAE
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• v.39 no.2
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• pp.59-74
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• 2024

Terrestrial cyanobacteria are extremely diverse. In urban areas, they can be found as black stains on the surface of building walls, stone monuments, or man-made structures. Many of the terrestrial cyanobacteria are still understudied. To expand knowledge of terrestrial cyanobacterial diversity, a polyphasic characterization was performed to identify 12 strains isolated from campus of University of the Ryukyus, Okinawa, Japan. Multigene phylogenetic analyses based on 16S rRNA gene and 16S-23S rRNA internal transcribed spacer (ITS) region showed that the isolated strains formed two independent subclades within Nodosilinea, and were distantly related to all described Nodosilinea species. The 16S-23S rRNA ITS secondary structures showed variations for D1-D1' and Box B domain, while V3 domain was almost identical among entire species of Nodosilinea, including the studied strains. In addition, a unique morphological character, i.e. forming nodule or spiral shape, was also observed in certain studied strains. According to polyphasic characterization, Nodosilinea coculeatus sp. nov. and Nodosilinea terrestrialis sp. nov., were proposed as two new species of terrestrial cyanobacteria from Okinawa.

• Smart Structures and Systems
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• v.18 no.1
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• pp.53-74
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• 2016

This paper presents an experimental study on constructing a tunable secondary suspension for high-speed trains using magneto-rheological fluid dampers (referred to as MR dampers hereafter), in the interest of improving lateral ride comfort. Two types of MR dampers (type-A and type-B) with different control ranges are designed and fabricated. The developed dampers are incorporated into a secondary suspension of a full-scale high-speed train carriage for rolling-vibration tests. The integrated rail vehicle runs at a series of speeds from 40 to 380 km/h and with different current inputs to the MR dampers. The dynamic performance of the two suspension systems and the ride comfort rating of the rail vehicle are evaluated using the accelerations measured during the tests. In this way, the effectiveness of the developed MR dampers for attenuating vibration is assessed. The type-A MR dampers function like a stiffness component, rather than an energy dissipative device, during the tests with different running speeds. While, the type-B MR dampers exhibit significant damping and high current input to the dampers may adversely affect the ride comfort. As part of an ongoing investigation on devising an effective MR secondary suspension for lateral vibration suppression, this preliminary study provides an insight into dynamic behavior of high-speed train secondary suspensions and unique full-scale experimental data for optimal design of MR dampers suitable for high-speed rail applications.

• Journal of Photoscience
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• v.9 no.2
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• pp.66-69
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• 2002

Zinc chlorin 1 possessing tertiary 3$^1$_hydroxy and 13$^1$-oxo groups was synthesized as a model for the antenna chlorophylls of photosynthetic green bacteria. Self-aggregation of 1 in nonpolar organic solvents was examined and compared to 2 and 3 possessing a secondary and primary 3$^1$_hydroxy group, respectively. Zinc chlorin 1 self-aggregated in I％(v/v) CH$_2$Cl$_2$-hexane to form oligomers and showed a red-shifted Qy maximum at 704 nm compared to the monomer (648 nm in CH$_2$CI2$_2$). This red-shift is larger than that of 3$^1$S-2 (648 to 697 nm) and comparable to that of3$^1$R-2 (648 to 705 nm), but smaller than that of 1 (648 to 740 nm), indicating that while a single 3$^1$-methyl group (primary to secondary OH) suppressed tight and/or extended aggregation, the additional 3$^1$-methyl group (secondary to tertiary OH) did not further suppress aggregation. The relative stability of the aggregates was in the order 3> 3$^1$R-2∼ 1 > 3$^1$S-2 as determined by visible spectral analyses. Molecular modeling calculations on oligomers of zinc chlorins 1, 3$^1$ R-2 and 3 gave similar well-ordered energy-minimized structures, while 3 stacked more tightly than 3$^1$ R- 2 and 1. In contrast, 3$^1$S-2 gave a relatively disordered (twisted) structure. The calculated oligomeric structures could explain the visible spectral data of 1-3 in nonpolar organic solvents. Moreover, self- aggregation of synthetic zinc 13$^1$_oxo-hlorins 4-6 possessing a 2-hydroxyethyl, 3-hydroxypropyl and 3- hydroxy-I-propenyl group at the 3-position in nonpolar organic solvents was discussed.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3248-3252
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• 2012

Vibrio extracellular metalloprotease (vEP), secreted from Vibrio vulnificus, shows various proteolytic function such as prothrombin activation and fibrinolytic activities. Premature form of vEP has an N-terminal (nPP) and a C-terminal (C-ter100) region. The nPP and C-ter100 regions are autocleaved for the matured metalloprotease activity. It has been proposed that two regions play a key role in regulating enzymatic activity of vEP. Especially, C-ter100 has a regulatory function on proteolytic activity of vEP. C-ter100 domain has been cloned into the E. coli expression vectors, pET32a and pGEX 4T-1 with TEV protease cleavage site and purified using gel-filtration chromatography followed by affinity chromatography. To understand how C-ter100 modulates proteolytic activity of vEP, structural studies were performed by heteronuclar multi-dimensional NMR spectroscopy. Backbone $^1H$, $^{15}N$ and $^{13}C$ resonances were assigned by data from standard triple resonance and HCCH-TOCSY experiments. The secondary structures of vEP C-ter100 were determined by TALOS+ and CSI software based on hydrogen/deuterium exchange. NMR data show that C-ter100 of vEP forms a ${\beta}$-barrel structure consisting of eight ${\beta}$-strands.

• Wind and Structures
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• v.30 no.5
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• pp.525-532
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• 2020

This work numerically investigates the effects of Reynolds number Re_D (= 100 - 150), cross-sectional aspect ratio AR = ( 0.25 -1.0), and attack angle α (= 0° - 90°) on the forces, Strouhal number, and wake of an elliptical cylinder, where Re_D is based on the freestream velocity and cylinder cross-section height normal to the freestream flow, AR is the ratio of the minor axis to the major axis of the elliptical cylinder, and α is the angle between the cylinder major axis and the incoming flow. At Re_D = 100, two distinct wake structures are identified, namely 'Steady wake' (pattern I) and 'Karman wake followed by a steady wake (pattern II)' when AR and α are varied in the ranges specified. When Re_D is increased to 150, an additional wake pattern, 'Karman wake followed by secondary wake (pattern III)' materializes. Pattern I is characterized by two steady bubbles forming behind the cylinder. Pattern II features Karman vortex street immediately behind the cylinder, with the vortex street transmuting to two steady shear layers downstream. Inflection angle α_i = 32°, 37.5° and 45° are identified for AR = 0.25, 0.5 and 0.75, respectively, where the wake asymmetry is the greatest. The α_i effectively distinguishes the dependence on α and AR of force and vortex shedding frequency at either Re_D. In Pattern III, the Karman street forming behind the cylinder is modified to a secondary vortex street. At a given AR and α, Re_D = 150 renders higher fluctuating lift and Strouhal number than Re_D = 100.