• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.192-196
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• 2005

Key part of main equipment in a gas turbine may be likely to be damaged due to operation under high temperature, high pressure, high-speed rotation, etc. Accordingly, the cost for maintenance increases and the damaged parts may cause generation to stop. The number of parts for maintenance also increases, but diagnostics technology fur the maintenance actually does not catch up with the demand. Blades are made of precipitation hardening Ni superalloy IN738 and the like for keeping hot strength. The surface of a blade is thermal-sprayed, using powder with main compositions such as Ni, Cr, Al, etc. in order to inhibit hot oxidation. Conventional regular maintenance of the coating layer of a blade is made by FPI (Fluorescent Penetrant Inspection) and MTP (Magnetic Particle Testing). Such methods, however, are complicated and take long time and also require much cost. In this study, defect diagnostics were tested for the coating layer of an industrial gas turbine blade, using an infraredthermography camera. Since the infrared thermography method can check a temperature distribution on a wide range of area by means of non-contact, it can advantageously save expenses and time as compared to conventional test methods. For the infrared thermography method, however, thermo-load must be applied onto a tested specimen and it is difficult to quantify the measured data. To solve the problems, this essay includes description about producing a specimen of a gas turbine blade (bucket), applying thermo-load onto the produced specimen, photographing thermography images by an infrared thermography camera, analyzing the thermography images, and pre-testing for analyzing defects on the coating layer of the gas turbine blade.

• Journal of Trauma and Injury
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• v.37 no.2
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• pp.97-105
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• 2024

Purpose: Massive transfusion protocols (MTPs) implementation improves clinical outcomes of the patient's resuscitation with hemorrhagic trauma. Various predictive scoring system have been used and studied worldwide to improve clinical decision. However, such research has not yet been studied in Korea. This systematic review aimed to assess the predictors of MTPs activation in patients with trauma in Korea. Methods: The PubMed, Embase, Cochrane Library, Research Information Sharing Service databases, KoreaMed, and KMbase were searched from November 2022. All studies conducted in Korea that utilized predictors of MTPs activation in adult patients with trauma were included. Results: Ten articles were eligible for analysis, and the predictors were assessed. Clinical assessments such as systolic and diastolic blood pressure, shock index (SI), prehospital modified SI, modified early warning system (MEWS) and reverse SI multiplied by the Glasgow Coma Scale (rSIG) were used. Laboratory values such as lactate level, fibrinogen degradation product/fibrinogen ratio, and rotational thromboelastometry (ROTEM) were used. Imaging examinations such as pelvic bleeding score were used as predictors of MTPs activation. Conclusions: Our systematic review identified predictors of MTPs activation in patients with trauma in Korea; predictions were performed using tools that requires clinical assessments, laboratory values or imaging examinations only. Among them, ROTEM, rSIG, MEWS, SI, and lactate level showed good effects for predictions of MTPs activation. The application of predictors for MTP's activation should be individualized based on hospital resource and skill set, also should be performed as a clinical decision supporting tools.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.3
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• pp.75-85
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• 2017

A method to estimate hourly temperature profiles on calm and clear nights was developed based on temporal changes of inversion height and strength. A meteorological temperature profiler (Model MTP5H, Kipp and Zonen) was installed on the rooftop of the Highland Agriculture Research Institute, located in Daegwallyeong-myeon, Pyeongchang-gun, Gangwon-do. The hourly vertical distribution of air temperature was measured up to 600 m at intervals of 50 m from May 2007 to March 2008. Temperature and relative humidity data loggers (HOBO U23 Pro v2, Onset Computer Corporation, USA) were installed in the Jungdae-ri Valley, located between Gurye-gun, Jeollanam-do and Gwangyang-si, Jeollanam-do. These loggers were used to archive measurements of weather data 1.5 m above the surface from October 3, 2014, to November 23, 2015. The inversion strength was determined using the difference between the temperature at the inversion height, which is the highest temperature in the profile, and the temperature at 100 m from the surface. Empirical equations for the changes of inversion height and strength were derived to express the development of temperature inversion on calm and clear nights. To estimate air temperature near the ground on a slope exposed to crops, the equation's parameters were modified using temperature distribution of the mountain slope obtained from the data loggers. Estimated hourly temperatures using the method were compared with observed temperatures at 19 weather sites located within three watersheds in the southern Jiri-mountain in 2015. The mean error (ME) and root mean square error (RMSE) of the hourly temperatures were $-0.69^{\circ}C$ and $1.61^{\circ}C$, respectively. Hourly temperatures were often underestimated from 2000 to 0100 LST the next day. When temperatures were estimated at 0600 LST using the existing model, ME and RMSE were $-0.86^{\circ}C$ and $1.72^{\circ}C$, respectively. The method proposed in this study resulted in a smaller error, e.g., ME of $-0.12^{\circ}C$ and RMSE of $1.34^{\circ}C$. The method could be improved further taking into account various weather conditions, which could reduce the estimation error.

• Journal of Life Science
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• v.20 no.7
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• pp.1019-1026
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• 2010

Obesity and being overweight are strongly associated with the development of metabolic disease such as diabetes, hypertension, dyslipidemia. High-fat diet (HFD) is one of the most important factors which cause obesity. In this study, C57BL/6 mice were treated with a HFD for 22 weeks in order to induce obesity and hyperglycemia. Twenty-two weeks later, body weight and plasma glucose level of the HFD group were significantly increased, compared with the normal diet (ND) group. Intra-peritoneal glucose tolerance test (IPGTT) showed glucose intolerance in the HFD group compared with the ND group. These results confirmed that a HFD induced obesity and hyperglycemia in C57BL/6 mice. Plasma levels of triglyceride (TG) and total cholesterol (TC) were increased in the HFD group compared with the ND group. Hepatic levels of TG and TC were also increased by a HFD. To investigate the alteration of lipid metabolism in liver, proteins which are related to lipid metabolism were observed. Among lipid synthesis related enzymes, fatty acid synthase (FAS) and glycerol phosphate acyl transferase (GPAT) were significantly increased in the HFD group. Apolipoprotein B (apoB) and microsomal triglyceride transport protein (MTP), which are related to lipid transport, were significantly increased in the HFD group. Interestingly, protein level and phosphorylation of AMP-activated protein kinase (AMPK), which is known as a metabolic regulator, were significantly increased in the HFD group compared with the ND group. In the present study we suggest that HFD may physiologically increase the proteins which are related with lipid synthesis and lipid transport, but that HFD may paradoxically induce the activation of AMPK.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.4
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• pp.590-595
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• 2008

The aim of our study was to research the effect of overfeeding on plasma parameters and mRNA expression of genes associated with hepatic lipogenesis in the Sichuan white goose and Landes goose. Fifty-four male Landes geese and 57 male Sichuan white geese were hatched on the same day under the same feeding conditions. After overfeeding for 14 days, (1) extrahepatic adipose tissues grew greatly in the Sichuan white geese, while more lipid accumulated in liver tissue in the Landes geese. (2) Sichuan white geese had a higher plasma concentration of triacylglycerols (TG), lipoproteins and insulin than the Landes geese. However, the Landes geese exhibited higher increase of plasma concentrations of TG, lipoproteins and insulin, with greater decrease of the diacylglycerol acyltransferase 2 (DGAT2) activity and DGAT2 mRNA level and a smller decrease of plasma glucose concentration. In addition, the mRNA level of MTP and LPL in liver was down- and up- regulated by overfeeding, respectively. (3) The correlations between the activity of LPL and the proportions of subcutaneous adipose tissue, abdominal adipose tissue, and liver weight, and the plasma concentration of VLDL were different in the two breeds. (4) The proportion of fatty liver weight was positively correlated to plasma concentrations of VLDL and TG in the overfed Sichuan white geese. Such a relationship did not exist in the Landes geese. (5) The activity of DGAT2 and its mRNA abundance in liver had significant negative correlations with the TG content in liver lipid and plasma insulin level in the Landes geese, while in the Sichuan white geese they had negative correlation (p>0.05) with TG concentration in liver lipid and had significant positive correlation with VLDL and TG concentrations in plasma.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.505-518
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• 2023

The key to invasive pest management lies in preemptive action. However, most current research using species distribution models is conducted after an invasion has occurred. This study modeled the potential distribution of the globally notorious sweet potato pest, the sweet potato weevil(Cylas formicarius), that has not yet invaded Korea using MaxEnt. Using global occurrence data, bioclimatic variables, and topsoil characteristics, MaxEnt showed high explanatory power as both the training and test areas under the curve exceeded 0.9. Among the environmental variables used in this study, minimum temperature in the coldest month (BIO06), precipitation in the driest month (BIO14), mean diurnal range (BIO02), and bulk density (BDOD) were identified as key variables. The predicted global distribution showed high values in most countries where the species is currently present, with a significant potential invasion risk in most South American countries where C. formicarius is not yet present. In Korea, Jeju Island and the southwestern coasts of Jeollanam-do showed very high probabilities. The impact of climate change under shared socioeconomic pathway (SSP) scenarios indicated an expansion along coasts as climate change progresses. By applying the 10th percentile minimum training presence rule, the potential area of occurrence was estimated at 1,439 km² under current climate conditions and could expand up to 9,485 km² under the SSP585 scenario. However, the model predicted that an inland invasion would not be serious. The results of this study suggest a need to focus on the risk of invasion in islands and coastal areas.