• Journal of the Korean Society for Heat Treatment
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• v.29 no.1
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• pp.15-23
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• 2016

The effects of austenitizing temperature and cooling rate on precipitation behavior and tensile properties were investigated in an Mn-Mo-Nb-V pressure vessel steel. During austenitizing, it was shown that the austenite coarsening was somewhat suppressed by undissolved NbC. After cooling from austenitizing, the microstructure of all the steels mainly consisted of upper bainite. However, the steel comprised a little lower bainite and martensite in the case of aqua oil quenching from $1000^{\circ}C$, which would be due to increased hardenability by partly dissolved Nb and comparatively large austenite grains. The average size of NbC in austenite at higher temperature was analyzed to be smaller than that at lower temperature because of the more dissolution. It was found that the NbC did not grow much during fast cooling from austenitizing. Meanwhile, the NbC grew much during slow cooling, probably due to wide temperature range of cooling and sufficiently long time for NbC to grow. It was conjectured the V precipitates newly formed and/or grew during cooling from austenitizing and during tempering. On the other hand, the formation of NbC was almost completed before tempering and little more precipitated during tempering. Among the tempered steels, the steel which was fast cooled from $1000^{\circ}C$ showed the highest tensile strength, which seemed to come from the microstructure of fine upper bainite and some low temperature phases as well as the comparatively fine NbC precipitates.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.214-217
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• 2022

In the maritime digital forensic part, it is very important and difficult process that analysis of data and information with vessel navigation system's binary log data for situation awareness of maritime accident. In recent years, analysis of vessel's navigation system's trajectory information is an essential element of maritime accident investigation. So, we made an experiment about corruption with various memory device in navigation system. The analysis of corruption test in seawater give us important information about the valid pulling time of sunken ship for acquirement useful trajectory information.

• Journal of Korea Multimedia Society
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• v.13 no.3
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• pp.430-437
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• 2010

It is essential for living donor liver transplantation that surgeon must understand the hepatic vessel structure to improve the success rate of operation. In this paper, we extract the liver boundary without other surrounding structures such as heart, stomach, and spleen using the contrast enhanced MDCT liver image sequence. After that, we extract the major hepatic veins (left, middle, right hepatic vein) with morphological filter after review the basic structure of hepatic vessel which reside in segmented liver image region. The purpose of this study is provide the overall status of transplantation operation with size estimation of resection part which is dissected along with the middle hepatic vein. The method of liver extraction is as follows: firstly, we get rid of background and muscle layer with gray level distribution ratio from sampling process. secondly, the coincident images match with unit mesh image are unified with resulted image using the corse coordinate of liver and body. thirdly, we extract the final liver image after expanding and region filling. Using the segmented liver images, we extract the hepatic vessels with morphological filter and reversed the major hepatic vessels only with a results of ascending order of vessel size. The 3D reconstructed views of hepatic vessel are generated after applying the interpolation to provide the smooth view. These 3D view are used to estimate the dissection line after identify the middle hepatic vein. Finally, the volume of resection region is calculated and we can identify the possibility of successful transplantation operation.

• Korean Journal of Pharmacognosy
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• v.37 no.3
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• pp.143-150
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• 2006

Decoction of oriental medicinal preparation is prepared in various manners, and changes of chemical constituents might be occurred depending on the processing techniques. The present study was undertaken to investigate the phγsio-chemical and pharmacological equivalence between two extraction methods of Nokyong-sagunja-Tang. Samples were Prepared as follows ; Sample-I was prepared by simultaneously extracting Sagunja-Tang and velvet antler in one vessel. Sample-lI was prepared by adding velvet antler exact to the water extract of Sagunja-Tang. Both sanples showed similar results of physiochemical parameters such as pH, yield, TLC and HPLC chromatogram, and contents of ginsenoside $Rb_1$ and glycyrrhizin. Also, there were little different between two samples in pharmacological effects such as DPPH free radical scavenging effect, and inhibitory effects on xanthine oxidase, hyaluronidase, trypsin, TBA-Rs formation and hemolysis in vitro. And both samples showed no significant difference in antifatigue activities in mice. These results suggest that there might be little difference between two extraction process when velvet antler added to Sagunia-Tang.

• Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.67-73
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• 2014

The oil in mackerel muscle was extracted using an environment friendly solvent, supercritical carbon dioxide (SC-$CO_2$) at a semibatch flow extraction process and an n-hexane. The SC-$CO_2$ was maintained at a temperature of $45^{\circ}C$ under pressures ranging from 15 to 25 MPa. The flow rate of $CO_2$ (27 g/min) was constant during the entire 2 h extraction period. The fatty acid composition of the oil was analyzed using gas chromatography (GC). Significant concentrations of eicosapentaenoic acid (EPA) acid and docosahexaenoic acid (DHA) acid were present in the SC-$CO_2$ extracted oil. The oil extracted using SC-$CO_2$ exhibited increased stability compared with n-haxane extracted oil. Particles of mackerel oil together with the biodegradable polymer, polyethylene glycol (PEG) were formed using a gas saturated solution process (PGSS) with SC-$CO_2$ in a thermostatted stirred vessel. Different temperatures ($45-55^{\circ}C$), pressures (15-25 MPa) and a nozzle size $400{\mu}m$ were used for PGSS with a 1 h reaction time. The stability of mackerel oil in the particles did not changed significantly.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.486-489
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• 1996

A simple, rapid, specific and sensitive method for the detection of serum hepatitis C virus (HCV) RNA using the reverse transcription-polymerase chain reaction (RT-PCR) technique without conventional RNA extraction was developed. HCV template RNA from serum was obtained by boiling the serum at $95^{\circ}C$ for 2 min, cooling rapidly in ice and removing the proteins by cetrifugation. RT-PCR amplifications including the reverse transcription and first PCR amplification were performed in one vessel containing both of reverse transcriptase and Taq DNA polymerase. The detection of HCV RNA from $10^{-3}{\mu}l$. serum was possible with this method. The suitability of this method for clinical analysis was evaluated by assaying HCV RNA in 225 patient samples including anti-HCV antibody negatives (13 samples) and positives (212 samples) by enzyme-linked immunosorbent assay test (ELISA). Detections of HCV RNA with this method were in 4 of 13 anti-HCV antibody negative samples (30.8%) and 95 of 212 positive samples (44.8%). The present method can be completed in 1 hr and has a wide range of application for the clinical utilities to determine the viral RNAS.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.10
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• pp.1391-1396
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• 2011

Houttuynia cordata Thunb powder (0.05 g) was placed in a stainless vessel containing 10 mL of water, and subcritical water (SCW) extraction was carried out at various temperatures (50, 100, 200, and $300^{\circ}C$) for 10, 30, and 60 min. SCW treatment significantly affected physiologically important compounds, antioxidant activity, and acetylcholinesterase inhibitory activity of H. cordata Thunb extracts. H. cordata Thunb extracted at $300^{\circ}C$ for 30 min had the highest quercetin content, DPPH radical scavenging activity, total phenolic content, and acetylcholinesterase inhibitory activity, whereas the extract at $100^{\circ}C$ for 10 min possessed the highest flavonoid content. The highest ABTS radical scavenging activity was found in H. cordata Thunb extracted at 200 and $300^{\circ}C$ for 60 min. These results indicate that SCW extraction might be a useful processing method for obtaining valuable materials from H. cordata Thunb.

• Analytical Science and Technology
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• v.11 no.4
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• pp.281-291
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• 1998

An analytical method for the simultaneous measurement of trace Cu, Sn, and Bi in blood and urine has been investigated by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Microwave oven was used for the pretreatment of blood samples using nitric acid and hydrogen peroxide in a closedvessel digestion system with 1 mL whole blood for 8 minutes. Amberlite IRC-718 resin was used as a solid phase in solid-liquid extraction technique for the removal of matrix interferences such as Na, S, P, and other polyatomic ion species. Detection limits for Cu, Sn, and Bi by this method were 0.000375 ng/mL, 0.000297 ng/mL, and 0.000174 ng/mL, respectively. Recoveries of 99.1% for Cu, 102.5% for Sn, and 98.4% for Bi were obtained for the standard spiked NIST SRM 955a blood sample. The developed method was applied for whole real blood and urine samples.

• KIPS Transactions on Software and Data Engineering
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• v.7 no.9
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• pp.345-350
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• 2018

This study is an algorithm for detecting vein pattern features important for finger vein recognition. The feature detection algorithm is important because it greatly affects recognition results in pattern recognition. The recognition rate is degraded because the reference is changed according to the finger position change. In addition, the image obtained by irradiating the finger with infrared light is difficult to separate the image background and the blood vessel pattern, and the detection time is increased because the image preprocessing process is performed. For this purpose, the presented algorithm can be performed without image preprocessing, and the detection time can be reduced. SWDA (Down Slope Trace Waveform) algorithm is applied to the finger vein images to detect the fingertip position and vein pattern. Because of the low infrared transmittance, relatively dark vein images can be detected with minimal detection error. In addition, the fingertip position can be used as a reference in the classification stage to compensate the decrease in the recognition rate. If we apply algorithms proposed to various recognition fields such as palm and wrist, it is expected that it will contribute to improvement of biometric feature detection accuracy and reduction of recognition performance time.

• The Journal of Korean Medicine
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• v.23 no.4
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• pp.161-168
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• 2002

Objectives: Hwangryunhaedok-tang (Huang-lian-jie-du-tang, HRHDT, 黃連解毒湯) is a traditional Korean herbal medicine that is formulated with Coptidis Rhizoma, Phellodendri Cortex, Scutellariae Radix and Gardeniae Fructus. HRHDT is cold (寒) and bitter (苦) in nature and has general properties of clearing heat and detoxifying (淸熱解毒), strengthening the stomach and settling the liver (健胃平肝), and reducing inflammation, fever and swelling. This formula can prevent and treat artherosclerosis, hyperplasia of the endothelium, cerebral fluid circulation, cerebral vascular deterioration through aging, impairment of neurotransmitters, or disruption of the functioning of the cerebral cortex following infection or trauma. The purpose of the study reported here was to determine the neuroprotective effect of HRHDT on global ischemia induced by 4-vessel occlusion in Wistar rats. Methods: HRHDT extract was lyophilized after extraction with 85% methanol and 100% water. Rats were induced to 10 minutes of forebrain ischemia by 4-vessel occlusion (4-VO) and reperfused again. HRHDT was administered with a dose of 100 mg/kg, and 500 mg/kg of 85% methanol extracts and 100 mg/kg of 100% water extracts, respectively, at 0 min and 90 min after 4-VO. Rats were killed at 7 days after ischemia and the number of CA1 pyramidal neurons was counted in hippocampal sections stained with cresyl violet. Results: Body temperature of animals showed no significant difference between saline-treated groups and HRHDT extracts-treated groups until 5 hours of reperfusion. This result indicated that neuroprotective effects of HRHDT extracts were not due to hypothermic effects. The administration of HRHDT showed a significant neuroprotective effect on hippocampal CA1 neurons at 7 days after ischemia compared to the saline-treated group (P<0.001). HRHDT methanol extracts of 100 mg/kg, 500 mg/kg and HRHDT water extracts of 100 mg/kg showed 88.5%, 98.3% and 95.1 % neuroprotection, respectively. Conclusions: The results of this study demonstrate that administration of HRHDT is highly effective in reducing neuronal damage in response to transient global cerebral ischemia. HRHDT may involve many mechanisms that might account for its high degree of efficacy. A number of factors including free radicals, glutamate, calcium overload, NO, and various cytokines have been proposed to have an important role in causing neuronal death after short periods of global ischemia. Further studies are needed to know the neuroprotective mechanisms of HRHDT.