• Title/Summary/Keyword: Super growth

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Effect of Grain Size on Corrosion Resistance and High Temperature Oxidation Behavior of 22Cr-15Ni-5W Super Austenitic Stainless Steels (22Cr-15Ni-5W 슈퍼 오스테나이트계(系) 스테인리스강(鋼)의 고온산화(高溫酸化) 및 내식성(耐蝕性)에 미치는 결정립(結晶粒) 크기의 영향(影響))

  • Kim, H.J.;Lee, H.W.;Lee, J.M.;Kang, C.Y.
    • Journal of Power System Engineering
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    • v.10 no.3
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    • pp.51-57
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    • 2006
  • The effect of grain size on corrosion resistance and high temperature oxidation behavior was studied in 22Cr-15Ni-5W super austenitic stainless steels for desulfurization equipment as a heat power station. In the high temperature oxidation test, oxidation rate was increased as the temperature increased from $600^{\circ}C\;to\;800^{\circ}C$. In vapor, oxidation rate was faster than that in air. Because the vapor was inhibited nucleation of $Cr_2O_3$ film. And the high temperature oxidation resistance at $600^{\circ}C{\sim}800^{\circ}C$ was excellent from all specimens and specimen of the smallest grain size was the most excellent. Because increasing of diffusion course through the grain-boundary was promoted nucleation and growth of $Cr_2O_3$ film. In the test temperature at $600^{\circ}C{\sim}800^{\circ}C$, Cr rich round particle oxide was formed in air, whereas Fe rich needle type oxide was developed in vapor.

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Inhibitory Effects of Super Reductive Water on Plant Pathogenic Fungi

  • Hur, Jae-Seoun;Kim, Hae-Jin;Oh, Soon-Ok;Koh, Young-Jin;Kwak, Young-Se;Lee, Choong-Il
    • The Plant Pathology Journal
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    • v.18 no.5
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    • pp.284-287
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    • 2002
  • The antifungal activity of super reductive water (SRW) against plant pathogenic fungi was examined to extend its application to integrated pest management (IPM) for plant diseases. Diluted solutions ($\times$1/10, $\times$1/25, and $\times$1/50) of SRW inhibited fungal growth of kiwifruit soft rot pathogen, Diaporthe actinidiae, in a concentration dependent manner, When kiwifruits were inoculated on wounds with mycelium blocks, stock and diluted solutions successfully inhibited the disease development. In addition to the high pH of the SRW, fungistatic activity was also considered as the cause of the antifungal effect against the pathogen. Whereas conidial germination of Magnaporthe grisea was not affected by the diluted SRW solutions, appressorium formation was significantly inhibited in a concentration dependent manner, With little harmfulness to human health and environment SRW could be used to control plant pathogenic fungi, particularly appressorium-forming fungal pathogens.

Mechanical Characteristics and Fatigue Crack Propagation of Super Duplex Stainless Steel by Distribution of Austenite (오스테나이트 분포에 따른 수퍼 2상 스테인리스강의 기계적 특성과 피로균열 진전거동)

  • Do, J.Y.;Lee, S.K.;Ahn, S.H.;Nam, K.W.;Kang, C.Y.
    • Journal of the Korean Society for Heat Treatment
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    • v.14 no.4
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    • pp.205-211
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    • 2001
  • The characteristics of super duplex stainless steel were investigated on its fibrous structure and dispersed structure. These structures consist of various volume fractions and distributions of the austenite phase that were obtained by changing the heat treatment temperature and cycle. The fibrous structure had higher austenite volume fraction than dispersed structure on the same temperature. As the austenite volume fraction increased in both structures, tensile strength and elongation increased, but hardness decreased. Fatigue life of fibrous structure parallel to rolling direction was shorter than that of perpendicular to rolling direction. Fatigue life of dispersed structure was longer than parallel fibrous structure, and shorter than perpendicular fibrous structure. Fatigue crack propagation rate of fibrous structure was faster than that of dispersed structure.

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Water - Assisted Efficient Growth of Multi-walled Carbon Nanotubes by Thermal Chemical Vapor Deposition

  • Choi, In-Sung;Jeon, Hong-Jun;Kim, Young-Rae;Lee, Nae-Sung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.418-418
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    • 2009
  • Vertically aligned arrays of multi-walled carbon nanotube (MWCNT) on layered Si substrates have been synthesized by water-assisted thermal chemical vapor deposition (CVD). We studied changes in growth by parameters of growth temperature, growth time, rates of gas and annealing time of catalyst. Also, We grew CNTs by adding a little amount of water vapor to enhance the growth of CNTs. $H_2$, Ar, and $C_2H_2$ were used as carrier gas and feedstock, respectively. Before growth, Fe served as catalyst, underneath which AI were coated as an underlayer and a diffusion barrier, respectively, on the Si substrate. The water vapor had a greater effect on the growth of CNTs on a smaller thickness of catalyst. When the water vapor was introduced, the growth of CNTs was enhanced than without water. CNTs grew 1.29 mm for 10 min long by adding the water vapor, while CNTs were 0.73 mm long without water vapor for the same period of time. CNTs grew up to 1.97 mm for 30 min prior to growth termination under adding water vapor. As-grown CNTs were characterized by using scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and Raman spectroscopy.

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Deep Learning-based SISR (Single Image Super Resolution) Method using RDB (Residual Dense Block) and Wavelet Prediction Network (RDB 및 웨이블릿 예측 네트워크 기반 단일 영상을 위한 심층 학습기반 초해상도 기법)

  • NGUYEN, HUU DUNG;Kim, Eung-Tae
    • Journal of Broadcast Engineering
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    • v.24 no.5
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    • pp.703-712
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    • 2019
  • Single image Super-Resolution (SISR) aims to generate a visually pleasing high-resolution image from its degraded low-resolution measurement. In recent years, deep learning - based super - resolution methods have been actively researched and have shown more reliable and high performance. A typical method is WaveletSRNet, which restores high-resolution images through wavelet coefficient learning based on feature maps of images. However, there are two disadvantages in WaveletSRNet. One is a big processing time due to the complexity of the algorithm. The other is not to utilize feature maps efficiently when extracting input image's features. To improve this problems, we propose an efficient single image super resolution method, named RDB-WaveletSRNet. The proposed method uses the residual dense block to effectively extract low-resolution feature maps to improve single image super-resolution performance. We also adjust appropriated growth rates to solve complex computational problems. In addition, wavelet packet decomposition is used to obtain the wavelet coefficients according to the possibility of large scale ratio. In the experimental result on various images, we have proven that the proposed method has faster processing time and better image quality than the conventional methods. Experimental results have shown that the proposed method has better image quality by increasing 0.1813dB of PSNR and 1.17 times faster than the conventional method.

The Great Western Woodlands TERN SuperSite: ecosystem monitoring infrastructure and key science learnings

  • Suzanne M Prober;Georg Wiehl;Carl R Gosper;Leslie Schultz;Helen Langley;Craig Macfarlane
    • Journal of Ecology and Environment
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    • v.47 no.4
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    • pp.272-281
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    • 2023
  • Ecosystem observatories are burgeoning globally in an endeavour to detect national and global scale trends in the state of biodiversity and ecosystems in an era of rapid environmental change. In this paper we highlight the additional importance of regional scale outcomes of such infrastructure, through an introduction to the Great Western Woodlands TERN (Terrestrial Ecosystem Research Network) SuperSite, and key findings from three gradient plot networks that are part of this infrastructure. The SuperSite was established in 2012 in the 160,000 km2 Great Western Woodlands region, in a collaboration involving 12 organisations. This region is globally significant for its largely intact, diverse landscapes, including the world's largest Mediterranean-climate woodlands and highly diverse sandplain shrublands. The dominant woodland eucalypts are fire-sensitive, requiring hundreds of years to regrow after fire. Old-growth woodlands are highly valued by Indigenous and non-Indigenous communities, and managing impacts of climate change and the increasing extent of intense fires are key regional management challenges. Like other TERN SuperSites, the Great Western Woodlands TERN SuperSite includes a core eddy-covariance flux tower measuring exchanges of carbon, water and energy between the vegetation and atmosphere, along with additional environmental and biodiversity monitoring around the tower. The broader SuperSite incorporates three gradient plot networks. Two of these represent aridity gradients, in sandplains and woodlands, informing regional climate adaptation and biodiversity management by characterising biodiversity turnover along spatial climate gradients and acting as sentinels for ecosystem change over time. For example, the sandplains transect has demonstrated extremely high spatial turnover rates in plant species, that challenge traditional approaches to biodiversity conservation. The third gradient plot network represents a 400-year fire-age gradient in Eucalyptus salubris woodlands. It has enabled characterisation of post-fire recovery of vegetation, birds and invertebrates over multi-century timeframes, and provided tools that are directly informing management to reduce stand-replacing fires in eucalypt woodlands. By building regional partnerships and applying globally or nationally consistent methodologies to regional scale questions, ecological observatories have the power not only to detect national and global scale trends in biodiversity and ecosystems, but to directly inform environmental decisions that are critical at regional scales.

The fate of an infalling circumgalactic gas clump and the growth of the central massive black hole in a high-redshift quasar

  • Jo, Yongseok;Kim, Ji-hoon
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.35.1-35.1
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    • 2020
  • Since the discovery of SMBHs at z > 6, the growth spurt of a BH in a relatively short time—a few hundred Myr—has been a challenging topic for many observers and theorists. Super-Eddington accretion, major and minor merger have been compelling candidate machanisms to account for such growth. We introduce a passive scalar field to trace the infalling of circumgalactic gas clump onto high-z quasar. With the scalar field, we investigate e.g. where the most of the gas clump eventually reside in the host galaxy and how much gas is accreted onto the central massive black hole. In addition, we have studied the impact of thermal feedback of stars on the growth of black hole and the infalling gas. We will also discuss the future application of passive scalar field in e.g. minor and major mergers of high-z quasar.

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Determination of dietary Ca and P levels and their equivalence values of phytase and vitamin D3 for improved growth performance in weanling pigs

  • Ogola, Oketch Elijah;Choi, Jun Seung;Hong, Jun Seon;Kim, Yu Bin;Nawarathne, Shan Randima;Yu, Myunghwan;Heo, Jung Min
    • Korean Journal of Agricultural Science
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    • v.48 no.3
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    • pp.397-412
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    • 2021
  • In Experiment 1, the impact of using diets sufficient in P on the performance of weaned piglet growth with or without a super dose of phytase was investigated. One hundred and twelve piglets were randomized into four treatments with 7 replicates (4 piglets·cage-1). Bodyweight (BW), daily gain (ADG), daily intake (ADFI) and feed conversion ratios (FCR) were measured over three weeks. Treatments included a positive control (PC) with a Ca : P ratio of 0.80 : 0.50%. and the negative control (NC) had a Ca : P ratio of 0.60 : 0.50%. The PC plus phytase was denoted as PC+, and the NC with the phytase diet was designated as NC+. The PC diet was formulated to meet or exceed the NRC (2012) standards for pigs weighing 7 - 25 kgs. Better results were obtained with the PC diet (p > 0.1) compared to the NC diet. The super dose of phytase in the PC+ diet significantly improved the overall FCR (p < 0.1). For Experiment 2, the impact of different calcium (Ca)/phosphorous (P) ratios with or without supplementation of vitamin D3 was determined. Ninety-six piglets were randomized into four treatments with 6 replicates (4 piglets·cage-1). The PC, NC1 and NC2 diets had ratios of 0.80 : 0.50, 0.80 : 0.45, and 0.60 : 0.45%, respectively. The fourth diet (PCV) was the PC diet fortified with vitamin D3. Improved results were observed with the PC diet (p > 0.1) compared to the NC diets. Supplementing dietary 25-OH-D3 in the PCV diet led to numerically higher ADG and ADFI scores with lower FCR values at the early nursery stage (p = 0.0044), but the vitamin supplement did not significantly influence the growth.