• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.2
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• pp.75-82
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• 2005

Recently the needs of high reliable substances of high strength and high ductility are gradually increased with the development of aerospace industry. The characteristics of maraging steel has high ductililty, formability, corrosion resistant and high temperature strength and is easy to fabricate, weld and treat with heat, and maintain an invariable size even after heat treatment. e steels are furnished in the solution annealed condition and they achieve full properties through martensitic precipitation aging a relatively simple, low temperature heat treatment. As is true of the heat treating procedures, aging is a time/temperature dependent reaction. Therefore, the objective of this stud)'was consideration of fatigue characteristics according as Nb(niobium) content and time/temperature of heat treatment change. Also the stress analysis, fatigue lift, and stress intensity factor were compared with experiment results and FEA(finite element analysis) result. The maximum ftresses of)( Y, and Z axis direction showed about $2.12\times$10$^{2}$MPa, $4.40\times$10$^{2}$MPa and $1.32\times$10$^{2}$MPa respectively. The fatigue lives showed about $7\%$ lower FEA result than experiment result showing almost invariable error every analyzed cycle. Stress intensity factor of the FEA result was lower about $3.5~ 10\%$ than that of the experiment result showing that the longer fatigue crack ten添 the hi인or error. It considered that the cause for the difference was the modeled crack tip having always the same shape and condition regardless of the crack growth.

• Korean Journal of Materials Research
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• v.30 no.5
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• pp.231-238
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• 2020

The composition of martensite transformation in NiAl alloy is determined using pure nickel and aluminum powder by vacuum hot press powder metallurgy, which is a composition of martensitic transformation, and the characteristics of martensitic transformation and microstructure of sintered NiAl alloys are investigated. The produced sintered alloys are presintered and hot pressed in vacuum; after homogenizing heat treatment at 1,273 K for 86.4 ks, they are water-cooled to produce NiAl sintered alloys having relative density of 99 % or more. As a result of observations of the microstructure of the sintered NiAl alloy specimens quenched in ice water after homogenization treatment at 1,273 K, it is found that specimens of all compositions consisted of two phases and voids. In addition, it is found that martensite transformation did not occur because surface fluctuation shapes did not appear inside the crystal grains with quenching at 1,273 K. As a result of examining the relationship between the density and composition after martensitic transformation of the sintered alloys, the density after transformation is found to have increased by about 1 % compared to before the transformation. As a result of examining the relationship between the hardness (Hv) at room temperature and the composition of the matrix phase and the martensite phase, the hardness of the martensite phase is found to be smaller than that of the matrix phase. As a result of examining the relationship between the temperature at which the shape recovery is completed by heating and the composition, the shape recovery temperature is found to decrease almost linearly as the Al concentration increases, and the gradient is about -160 K/at% Al. After quenching the sintered NiAl alloys of the 37 at%Al into martensite, specimens fractured by three-point bending at room temperature are observed by SEM and, as a result, some grain boundary fractures are observed on the fracture surface, and mainly intergranular cleavage fractures.

• Journal of Acupuncture Research
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• v.18 no.6
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• pp.44-52
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• 2001

Objective : This study had been done to develop treatment and preventation on HIVD by using this result. Methods : To obtain this result, we examinated 51 case of patients who visit Dept. of Acupuncture and Moxibustion. Oriental Medical Hospital. Taejon University. diagnosed HIVD. Results : As a result of this examination, we detected the fact that reattack rate is 3.9% and it is important to exercise physically to prevent growing worse symptoms. And we develop further method of treatment to treat people more effectively. Detailed contents are as followed. Conclusion : We want to be put this knowledge to practical use on treating HIVD and think the study like this must be go on continuously.

• Korean Journal of Pharmacognosy
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• v.53 no.4
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• pp.181-191
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• 2022

As the incidence of skin cancer increases every year, non-surgical treatment methods for cancer are being sought. Esculetin, a natural dihydroxy coumarin, is attracting attention as a therapeutic agent for certain diseases, such as cancer, based on its broad pharmacological activity. In this study, the anticancer ability of esculetin was evaluated using the epidermoid carcinoma cell line A431. As a result of evaluating the apoptosis ability of esculetin by MTT assay, apoptosis was observed in a time-concentration-dependent manner regardless of the presence or absence of FBS. As a result of quantitative real-time PCR, esculetin reduced cyclin D1 mRNA in a time-concentration-dependent manner. In addition, as a result of western blotting, esculetin significantly inhibited phosphorylation of ERK, JNK, and p38 in a concentration-dependent manner. The results of this study suggest that esculetin has the potential to be used as an effective natural medicine for the treatment of skin cancer.

• Journal of Bio-Environment Control
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• v.30 no.1
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• pp.85-93
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• 2021

In hydroponic cultivation, in order to investigate the change of lettuce growth and physiologically active substances through CO2 tablet treatment in nutrient solution, we used a solid carbonated tablets commercially available in the Netherlands. The experiment consisted of 0.5-fold, 1-fold, and 2-fold treatment groups with no treatment as a control. As a result, the atmospheric CO2 concentration in the chamber after CO2 tablet treatment showed the highest value at 472.2 µL·L-1 in the 2-fold treatment zone immediately after treatment, and the pH in the nutrient solution decreased the most to pH 6.03 in the 2-fold treatment zone. After that, over time, the CO2 concentration and pH recovered to the level before treatment. Leaf width and leaf area of lettuce showed the highest values of 17.1cm and 1067.14 ㎠ when treated 2-fold with CO2 tablet, while fresh weight and dry weight of the above-ground part were highest at 63.87 g and 3.08 g in 0.5-fold treatment. The root length of lettuce was the longest (28.4 cm) in the control, but there was no significant difference in the fresh weight and the dry weight among the treatments. Apparently, it was observed that the root length of the lettuce was shortened by CO2 tablet treatment and a lot of side roots occurred. In addition, there was a growth disorder in which the roots turned black, but it was found that there was no negative effect on the growth of the above-ground part. As a result of analyzing the bioactive compounds of lettuce by CO2 tablet treatment, chlorogenic acid and quercetin were detected. As a result of quantitative analysis, chlorogenic acid increased by 249% compared to the control in 1-fold treatment, but quercetin decreased by 37%. As a result of comparing the DPPH radical scavenging ability showing antioxidant activity, the control and 0.5-fold treatment showed significantly higher values than the 1-fold and 2-fold treatments. This suggests that carbonated water treatment is effective in increasing the growth and bioactive compounds of hydroponic lettuce.

• Korean Institute of Interior Design Journal
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• v.23 no.5
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• pp.86-95
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• 2014

This study verified a hypothesis "treatment circumstance that considers character of children with autism has an effect on emotion stability", and I set the final aim to suggest emotional design elements according to treatment program and also to construct basic data about study of treatment circumstance of children with autism. So I conduct a survey of teachers of nine centers for the disabled about "satisfaction about treatment circumstance, importance of design elements of treatment circumstance that increase children's with autism stability, sensibility estimation about treatment circumstance" and committed statistical analysis. As the results, emotional design elements that have to be improved are the wall finishing material, the color of the wall, and the artificial lighting. The color of the wall has an effect on importance of treatment circumstance and emotional design elements influence 47% to satisfaction of treatment circumstance. It get the positive result about the hypothesis "treatment circumstance that considers character of children with autism has an effect on emotion stability".

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.4
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• pp.94-104
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• 2012

Purpose: The purpose of this paper is to report the effect of Korean medicine treatments on a female and a male patient who were infertile and failed to in vitro fertilization(IVF) treatment. Methods: The patients are a 30-year-old female who had been diagnosed with the ovulation dysfunction caused by the depression of ovarian function, and a 33-year-old male who had been diagnosed with sperm defect. The female patient alone underwent Korean medicine treatment after the eighth failure in IVF treatment and the male patient received Korean medicine treatment along with his wife after he failed in the first IVF treatment. The Korean medicine applied include herb-medicine administration, acupuncture, moxibustion, Jwa-Hun, and Du-Han-Jok-Yeol treatment. Results: Through Korean medicine treatment the female patient had succeeded in the IVF treatment and she also recovered completely from allergic rhinitis. The male patient whose wife also received Korean medicine treatment with him got his wife pregnant naturally. Conclusions: This result concludes that Korean medicine treatment is effective in infertile patients. Therefore, there needs to be more of subsequent research on infertile patients that is based on Korean medicine treatment.

• The Journal of Pediatrics of Korean Medicine
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• v.34 no.2
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• pp.90-108
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• 2020

Objectives The purpose of this study is to evaluate efficacy and safety of Mahaenggamsuktang for treating mycoplasma pneumonia in children based on the randomized controlled trials (RCTs). Methods Literatures were searched from OASIS, KISS, NDSL, CNKI, Cochrane, Embase and Pubmed, and the search was conducted on January 29, 2020. Only RCTs published since 2000 were included. Trials comparing Mahaenggamsuktang combined with antibiotics or antibiotics treatment alone for the treatment of mycoplasma pneumonia in children were included. Results 17 trials, including 2,241 participants with mycoplasma pneumonia were included in this review. As a result of the meta-analysis, total effective rate of combination of Mahaggamsuktang and antibiotics was 1.24 times higher than that of the antibiotics alone, which was statistically significant. Symptoms with fever, lung sounds, cough, chest X-ray lesion findings, wheezing were also significantly reduced in the treatment group with Mahaenggamseoktang and antibiotics. Also, Serum CRP level was significantly lower with combination treatment. The incidence of adverse reactions was lower in the treatment group with Mahaenggamseoktang and antibiotics, but it was not statistically significant. Conclusions As a result of meta-analysis, combination treatment of Mahaenggamseoktang and antibiotics seems significantly effective for the treatment of mycoplasma pneumonia in children. In order to have a higher level of evidence for efficacy and safety of Mahaenggamsuktang in treating mycoplasma pneumonia, additional RCTs with good qualities are required.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.485-492
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• 2017

The purpose of this study is to investigate the convergence effects of the experience of adult preventive care on the treatment satisfaction and the dental fear, and the survey was conducted from January to April 2017 for 292 adults of aged 20 years or older living in the metropolitan area. The collected data were subjected to $x^2-test$, t-test and multiple regression analysis using SPSS 22.0 program. Fluoride application was the most prevalent experience of adult preventive treatment, and the satisfaction level of the treatment was high in case of fluoride application was experienced. On the other hand, dental fear was lower if preventive scaling was experienced. As a result of multiple regression analysis, variables affecting patient satisfaction were experience of fluoride application, and the variables affecting dental fear level were oral health condition and preventive scaling experience. The result of this study was confirmed that the satisfaction level of treatment was increased and the dental fear was lowered. Therefore, improvement of oral health promotion can be expected by recognizing of the importance of preventive treatment and providing of the dental preventive service through oral health education.

• Journal of Acupuncture Research
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• v.33 no.3
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• pp.75-87
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• 2016

Objectives : The purpose of this study is to investigate the effects of acupuncture and moxibustion treatment at SP6(Sanyinjiao) on the temperature change of feet in healthy adults and evaluate whether SP6 has an effect on cold hypersensitivity of feet. Methods : Subjects of this study were 61 healthy adults consisting of 21 in the acupuncture treatment group, 21 in the moxibustion treatment group and 19 in the control group, selected at random. After starting the experiment, the subjects laid straight on their back and relaxed for 30 minutes. Pictures were then taken of their feet by DITI 3 times before and after treatment. The treatment was carried out by either 15 minutes of acupuncture or 2 pieces of moxibustion at SP6. Whilst the control group rested lying straight. After taking pictures the temperatures of LR2, GB42, ST42, KI1, center of the plantar, and center of the calcaneus were checked and the SPSS for Windows Version 20.0 was used to evaluate the statistical significance by the paired t-test, Wilcoxon signed-ranks test(in group) and the Mann-Whitney U-test(between the groups). Results : Some temperature changes before and after treatment were observed in each of the 12 areas, most of which were not significant. But as a result of comparing the temperature difference of all the samples without dividing the area of each group, the mean temperatures in the acupuncture and moxibustion group were significantly elevated. A comparison between the groups showed the mean temperature of the acupuncture and moxibustion group to be significantly elevated, more so than the control group. Conclusion : The result of this study suggests acupuncture and moxibustion treatment at SP6 has the effect of the rising temperature of feet temporarily.