• Corrosion Science and Technology
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• v.20 no.3
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• pp.158-168
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• 2021

Austenitic 316 stainless steel was irradiated with protons accelerated by an energy of 2 MeV at 360 ℃, the various defects induced by this proton irradiation were characterized with microscopic equipment. In our observations irradiation defects such as dislocations and micro-voids were clearly revealed. The typical irradiation defects observed differed according to depth, indicating the evolution of irradiation defects follows the characteristics of radiation damage profiles that depend on depth. Surface oxidation tests were conducted under the simulated primary water conditions of a pressurized water reactor (PWR) to understand the role irradiation defects play in surface oxidation behavior and also to investigate the resultant irradiation assisted stress corrosion cracking (IASCC) susceptibility that occurs after exposure to PWR primary water. We found that Cr and Fe became depleted while Ni was enriched at the grain boundary beneath the surface oxidation layer both in the non-irradiated and proton-irradiated specimens. However, the degree of Cr/Fe depletion and Ni enrichment was much higher in the proton-irradiated sample than in the non-irradiated one owing to radiation-induced segregation and the irradiation defects. The microstructural and microchemical changes induced by proton irradiation all appear to significantly increase the susceptibility of austenitic 316 stainless steel to IASCC.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.2D
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• pp.113-118
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• 2010

This paper presents an analysis of the instability phenomenon on motorways, with the aim of arriving at the definition of a control strategy suitable for keeping the flow stable. By using some results of the motorway reliability theory, a relationship and some flow characteristics is obtained, which shows that the existence of a reliability threshold critical for flow stability. The macroscopic flow characteristics corresponding to this threshold are very different in different situations, so that this control of flow stability requires the analysis of speed and density microscopic process surveyed on a cross section of the motorway carriage ways to be controlled. A method is presented, based on integrated moving average(IMA) analysis in real time of these processes, by which it is possible to detect the approach of instability before its effects become manifest, and to single out the proper control strategy in different situations.

• Nuclear Engineering and Technology
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• v.56 no.2
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• pp.715-727
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• 2024

During fast neutron imaging, besides the dark current noise and readout noise of the CCD camera, the main noise in fast neutron imaging comes from high-energy gamma rays generated by neutron nuclear reactions in and around the experimental setup. These high-energy gamma rays result in the presence of high-density gamma white spots (GWS) in the fast neutron image. Due to the microscopic quantum characteristics of the neutron beam itself and environmental scattering effects, fast neutron images typically exhibit a mixture of Gaussian noise. Existing denoising methods in neutron images are difficult to handle when dealing with a mixture of GWS and Gaussian noise. Herein we put forward a deep learning approach based on the Swin Transformer UNet (SUNet) model to remove high-density GWS-Gaussian mixture noise from fast neutron images. The improved denoising model utilizes a customized loss function for training, which combines perceptual loss and mean squared error loss to avoid grid-like artifacts caused by using a single perceptual loss. To address the high cost of acquiring real fast neutron images, this study introduces Monte Carlo method to simulate noise data with GWS characteristics by computing the interaction between gamma rays and sensors based on the principle of GWS generation. Ultimately, the experimental scenarios involving simulated neutron noise images and real fast neutron images demonstrate that the proposed method not only improves the quality and signal-to-noise ratio of fast neutron images but also preserves the details of the original images during denoising.

• Archives of Plastic Surgery
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• v.50 no.6
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• pp.615-620
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• 2023

Massive localized lymphedema (MLL) is a rare disease caused by the obstruction of lymphatic vessels with specific clinical morphological and radiological characteristics. People with morbid obesity are mainly affected by MLL. Lymphedema is easily confused with soft tissue sarcoma and requires differential diagnosis, both the possibility of an MLL and also carcinoma manifestations in the soft tissues. The possible causes of massive lymphedema include trauma, surgery, and hypothyroidism. This report is the first case of MLL treated surgically in the Russian Federation. Detailed computed tomography (CT) characteristics and an electron microscope picture of MLL are discussed. A 50-year-old woman (body mass index of 43 kg/m²) with MLL arising from the anterior abdominal wall was admitted to the hospital for surgical treatment. Its mass was 22.16 kg. A morphological study of the resected mass confirmed the diagnosis of MLL. We review etiology, clinical presentation, diagnosis, and treatment of MLL. We also performed an electron-microscopic study that revealed interstitial Cajal-like cells telocytes not previously described in MLL cases. We did not find similar findings in the literature. It is possible that the conduction of an ultrastructural examination of MLL tissue samples will further contribute to the understanding of MLL pathogenesis.

• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.103-111
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• 2004

There are some problems in evaluating the bearing capacity of decomposed granite soils by general equations on account of their inherent compressibility and crushability. In order to investigate this kind of the engineering characteristics on decomposed granite soils in detail, it is necessary to how the micro property of the single particle composing the granite soils, and then the relevance to the macro characteristics of the soils has to be cleared. The reason why the single particle properties are not studied is first the difficulty to find out some regulating parameters, and secondly little understanding of its significance. Furthermore, the water in the decomposed granite soils accelerates the particle crushing. Consequently, increasing of compressibility and decreasing of shear strength would occur. Actually, when the ground settlement is a big issue in the embanked ground using the decomposed granite soils, the sensitive change of compressibility due to the change of water content in the ground becomes conspicuous. In this study, the single particle strength characteristics are studied and microscopic particle shape analyses are performed. In addition the compressibility of the decomposed granite soils and water content effect on the compressibility are analysed based on the test results.

• Journal of the Mineralogical Society of Korea
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• v.30 no.3
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• pp.93-102
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• 2017

Heavy mineral provide an important information for sediment provenance as well as a potential submarine mineral resources. We compared the heavy mineral characteristics between Southeastern Yellow Sea Mud (SEYSM) and Southwestern Cheju Island Mud (SWCIM) surface sediments. We separated heavy minerals from 28 surface sediments in each mudbelt, and then carried out stereo-microscopic, field-emission scanning electron microscopic, energy dispersive spectroscopic and electron probe microanalysis to characterize the type, abundance, mineralogical properties and distribution pattern of heavy mineral. Amphibole and epidote, which are two major heavy minerals, account for more than 70% of total heavy minerals. Zircon and sphene contents are more abundant in SEYSM, whereas apatite and rutile contents are more abundant in SWCIM. Monazite only occurs in some area of SEYSM. Sphene and monazite content decrease to the south in SEYSM. Both garnet-zircon index (GZi) and rutile-zircon index (RuZi) are low in SEYSM but high in SWCIM. Amphiboles in SEYSM primarily correspond to hornblende, however those in SWCIM represent variable composition from pargasite, tshermakite, hornblende to tremolite. Garnets in SEYSM have high Mg and low Ca, but those in SWCIM have low Mg with variable Ca. Different heavy mineral characteristics between SEYSM and SWCIM suggests that sediments in each mudbelt have different provenances. Although this study implies that SEYSM sediment may mostly come from nearby Korean western rivers such as the Keum and Han rivers, this study does not suggest any idea of the source area of SWCIM sediment. Further study is needed to interpret the provenance and transportation mechanism of mudbelt sediments through the heavy mineral research for the river sediments flowing into the Yellow Sea and much more marine sediments.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.4
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• pp.554-562
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• 2008

In this study, we attempted to assess the efficacy of a method to improve the quality of prepared bread via the addition Poria cocos powder to wheat flour at a range of concentrations from $0{\sim}5%$. The approximate composition for Poria cocos powder was as follow: moisture 7.67%, crude protein 0.61%, crude fat 0.58%, crude ash 0.32%, and crude fiber 0.30%, when using the flour to which the Poria cocos powder had been added, specific volume, falling number, and dough yield values all increased with increasing concentrations of added Poria cocos powder. The result of our microscopic observations revealed a relative scarcity of larger starch granules, and the bread prepared with the Poria cocos powder evidenced a sparse structure. With regard to the Hunters color value measurements, the L value decreased with increasing concentrations of Poria cocos powder. but the a and b values evidenced an inverse relationship with the concentration of added powder. The texture, hardness, and adhesiveness characteristics of the bread decreased with increasing concentration of added Poria cocos powder. but the gumminess and chewiness of the bread increased. However, we noted no significant differences in the springiness and cohesiveness characteristics among the experimental groups assessed herein. In the sensory evaluation, the quality of the 2% or 3% Poria cocos powder breads was optimal in terms of its taste and flavor.

• Mycobiology
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• v.32 no.1
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• pp.1-5
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• 2004

The present study was carried out to investigate morphological characteristics of pseudosclerotia of Grifola umbellata formed by artificial cultures. Isolate G. umbellata DUM GUS-01 was obtained from sclerotium cultivated in field. The fungal isolate was cultured on PDYM broth, PDYMA(potato dextrose yeast malt agar) and oak sawdust media at $20^{\circ}C$ under the dark condition. G. umbellata DUM GUS-01 showed a volumetric increment of fungal lumps rather than mycelial growth. Particularly, G. umbellata DUM GUS-01 produced a large amount of melanin pigments in all culture treatments. The color of the fungal mass has been changed into grey gradually, and then formed melanized rind-like structure on its superficial part. The fungal structures which were covered with melanized rind-like layer were named as pseudosclerotia of G. umbellata. The pseudosclerotia of G. umbellata DUM GUS-01 formed a new white mycelial mass, which was swollen out of the melanized rind structure for its volumetric increment. When the pseudosclerotia were sectioned, their structure was discriminated from two structures such as a melanized rind-like structure layer formed by aggregation of aged mycelia and a white mycelial mass with high density. As results of scanning electron microscopic examination, the pseudosclerotia of G. umbellata DUM GUS-01 which were formed in in vitro conditions were similar to the sclerotia of G. umbellata cultivated in natural conditions except for the crystals formed in medula layer of natural sclerotia. Although size, solidity of rind structure and mycelial compactness of pseudosclerotia were more poor than those of natural sclerotia, the morphological structure and growth pattern of pseudosclerotia were very similar to those of natural sclerotia. Therefore, it is probable to induce pseudosclerotia to sclerotia of G. umbellata in in vitro conditions. Consequently, it seems that the induced pseudosclerotia can be used as inoculum sources to substitute natural sclerotia in field cultivation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.6
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• pp.116-126
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• 2016

In this study, lane-wise traffic flow characteristics were analysed on uninterrupted flow using a new notion of "lane-wise travel speed reversal (LTSR)" which is defined as a phenomena that travel speed in the median lane is lower than other lanes. Mathematical formulation was also proposed to calculate the strength of LTSR. The experiment road site is Seoul Outer Ring Expressway (Jayuro-IC~Jangsoo-IC), and travel trajectories for each four lane were collected for weekdays (Mon. through Fri.) during morning peak. Comparing lane-wise travel speeds for entire test road section, no LTSR was observed, meaning that the travel speed in the median lane is the fastest, followed by 2nd, 3rd, and 4th lane as in order. Howerver, the result of microscopic analysis using 100-meter discrete road section based data shows that LTSR occurs many times. Especially the strength of LTSR is higher in congestion area and freeway merge and diverge segment. It is expected that these results could be used as a fundamental data when establishing lane-by-lane traffic operation strategy and developing lane-wise traffic information collection and dissemination technology.

• The Korean Journal of Malacology
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• v.32 no.2
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• pp.133-139
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• 2016

The incubation time required for hatching of O. ocellatus were investigated through the processes of egg and embryonic developments by the dissecting microscopic and visual observations. And differences in ecological characteristics of the plankton mode of life or the benthic mode of life according to total numbers of the suckers on each short arm of the hatched juvenile larvae of O. ocellatus were studied by comparisons with other octopodidae species. Compared with the recent a few results reported by other researchers associated with the incubation time required for hatching by female adult mother of O. minor (73-90 days after spawning at $20.9-21.5^{\circ}C$ ranges), in this study, the incubation time required for hatching by female adult mother of O. ocellatus was 56-57 days after spawning at $11.0-20.4^{\circ}C$. Therefore, the incubation time required for hatching by female adult mother varied with Octopodidae species. In this studies, each ovarian egg laid by a female was connected to an egg string attaching to the surface of the wall or bottom of vacunt shell of Rapana venosa. Egg and embryonic developments of this species were studied in the indoor aquaria, in the specific gravity ranging 1.024-1.025. the hatched juvenile of O. ocellatus is 10.3 mm in the mean total length and 4.5 mm in mantle length, and each of its short arms has 18-20 suckers. The just hatched juvenile larvae of O. ocellatus enter the benthic mode of life (benthic larval stage) after hatching. In particular, regarding differences in ecological characteristics of the mode of life according to total numbers of the suckers, O. vulgaris may not need to have many suckers because they enter the planktonic mode of life after hatching, however O. ocellatus may need to have many suckers, because they should adapt to the benthic mode of life. And also the just hatched juvenile larvae of O. minor (bearing many suckers more than O. ocellatus) enter the benthic mode of life (benthic larval stage) after hatching. Therefore, the total number of the suckers on each short arm of the hatched juvenile larvae can be used for determining whether an octopus species has planktonic larval stages or benthic larval stage (benthic mode of life). In particular, The intracohort cannibalism phenomena appeared at the hatched juvenile larval stage because the larval stage of O. ocellatus and O. minor enter into the benthic larval stage in the early stage, unlike entering into the plaktonic larval stage in other Octopus species such as O. vulgaris: at this time, the early hatched larvae fed the late hatched larvae (they are the same species and almost same ages). Therefore, the intracohort cannibalism pheneomena occur in the just hatched juvenile stage of only O. ocellatus and O. minor.