• Journal of the Korean Society for Heat Treatment
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• v.10 no.3
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• pp.159-164
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• 1997

Non-alloyed and 1.0%Ni alloyed ductile cast iron were cast into the sand mold and metal mold, and finer graphite size was obtained in case of metal mold casting. Direct tempering after casting showed the slight increase of absorbed energy, which is largely due to the relieving of residual stress that is developed during casting. After austempering heat treatment, higher impact energy was obtained in case of metal mold casting than sand mold casting, which is due to the finer graphite size.

• Journal of the Korean institute of surface engineering
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• v.48 no.6
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• pp.275-282
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• 2015

The cost for maintenance (replacement cost) of Ni-superalloy components in plant industry is very expensive because of high unit price of INCONEL 718. A development of repairing technology using kinetic spray process can be very helpful for reducing the maintenance cost. However, it is very difficult to produce well-deposited INCONEL 718 layer showing high interfacial bond strength via kinetic spraying. Thus, INCONEL 718 was deposited on SCM 440 substrate and the interfacial properties were investigated, in order to elucidate the cause of hindrance to the bonding between INCONEL 718 layer and SCM 440 substrate. As a result, it was revealed that the dominant obstacle to the interfacial bonding was excessive compressive residual stress accumulated in the coating layer, resulting from low plastic-deformation susceptibility of INCONEL 718. Nevertheless, the bonding state was enhanced by the post heat-treatment through relieving the residual stress and generating a diffusion/metallurgical bonding between the INCONEL 718 deposit and SCM 440 substrate.

• Korean Journal of Materials Research
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• v.23 no.9
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• pp.483-488
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• 2013

Over the past few decades, high-nitrogen austenitic steels have steadily received greater attention since they provide a unique combination of high strength and ductility, good corrosion resistance, and non-magnetic properties. Recently, highnitrogen 18Mn-18Cr austenitic steels with enhanced strength have been developed and widely used for generator retaining rings in order to prevent the copper wiring from being displaced by the centrifugal forces occurring during high-speed rotation. The high-nitrogen austenitic steels for generator retaining ring should be expanded at room temperature and then stress relief annealed at around $400^{\circ}C$ to achieve the required mechanical properties. In this study, four kinds of high-nitrogen 18Mn-18Cr austenitic steels with different nitrogen content were fabricated by using a pressurized vacuum induction melting furnace, and then the effects of nitrogen content, cold working, and stress relieving on tensile properties were investigated. The yield and tensile strengths increased proportionally with increasing nitrogen content and cold working, and they further increased after stress relieving treatment. Based on these results, a semi-empirical equation was proposed to predict the tensile strength of highnitrogen 18Mn-18Cr austenitic steels for generator retaining rings. It will be a useful for the effective fabrication of high-nitrogen 18Mn-18Cr austenitic steels for generator retaining rings with the required tensile properties.

• The Journal of Korean Academic Society of Nursing Education
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• v.14 no.2
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• pp.273-281
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• 2008

Purpose: This study was performed to investigate the effects of aromatherapy on headache, stress and immune response of students with tension-type headache. Method: This study employed a two-group pre-post test study design. Data was collected from 44 subjects. Twenty-two subjects were assigned to the experimental group and received aromatherapy massage every other day for 3 weeks, but the other 22 subjects were in the control group and did not receive any intervention. Experiment had been conducted from Apr. 9 through Aug. 25, 2001 and intensity of headache, stress response (serum cortisol, life stress) and immune response(T-cell and natural killer cell ratio) were measured in the course of aromatherapy for both experimental group and control group. Data were analyzed by using $X^2$-test, t-test, Paired t-test and repeated measures ANOVA. Result: Headache scores, serum cortisol levels and life stress scores were significantly decreased in the experimental group after treatment compared to the control group. Conclusion: These findings is suggested that the aromatherapy could be an effective nursing intervention in relaxing and relieving the pain caused by tension-type headache for students.

• Journal of Society of Preventive Korean Medicine
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• v.25 no.2
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• pp.45-60
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• 2021

Objective : This study was aimed to review randomized controlled trials (RCTs) about whether aromatherapy relieves stress. Method : We searched document about criteria to use words like 'Aroma', 'Oil' and 'Stress'. The study included 24 RCTs which were selected by total 167 studies searched in Korean Journal by searching OASIS, ScienceON, KISS, RISS. Cases that cannot be performed alone are excluded. Results : We got 24 domestic standard documents. Of the 24 studies, 14 were for students, and 6 were for patients receiving hospital treatment. Among the 7 treatments, dry-inhalation was used 13 times, and necklace-inhalation was used 9 times. Of the 24 Studies, lavender oil was used 19 times and sweet orange was used 4 times. Among the 28 types of measuring instruments used, 10 related to the autonomic nervous system and 8 STAIs and VASs were used respectively. Conclusion : It was possible to conclude that aromatherapy was effective in relieving stress. Through further research, it is necessary to study effective oil mixing methods, methods for measuring subjective stress, multimodal intervention, and effective intervention periods.

• Corrosion Science and Technology
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• v.23 no.4
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• pp.266-277
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• 2024

Due to its good corrosion and heat resistance with excellent mechanical properties, 304L stainless steel is commonly used in the fabrication of spent nuclear fuel dry storage canisters. However, welds are sensitive to stress corrosion cracking (SCC) due to residual stress generation. Although SCC resistance can be improved by stress relieving the weld and changing the chloride environment, it is difficult to change corrosion environment for certain applications. Stress control in the weld can improve SCC resistance. Ultrasonic shot peening (USP) needs further research as compressive residual stresses and microstructure changes due to plastic deformation may play a role in improving SCC resistance. In this study, 304L stainless steel was welded to generate residual stresses and exposed to a chloride environment after USP treatment to improve SCC properties. Effects of USP on SCC resistance and crack growth of specimens with compressive residual stresses generated more than 1 mm from the surface were studied. In addition, correlations of compressive residual stress, grain size, intergranular corrosion properties, and pitting potential with crack propagation rate were determined and the improvement of SCC properties by USP was analyzed.

• The Journal of Pediatrics of Korean Medicine
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• v.13 no.1
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• pp.1-16
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• 1999

A literature study was progressed for oriental medical diagnosis and treatment for Jianwang(健忘) : forgetfulness(amnesia). In orental medicine, the reason of Jianwang(健忘) was congenital insufficiency(稟賦不足), meditational excessiveness(思慮過多), deficiency of heart(心虛), phlegm retention(痰飮), deficiency of kidney(腎裏), breakdown of the normal physiological coordination between the heart and the kidney(心腎不交), blood stasis(瘀血). The method of medical treatment was invigorating vital energy and enriching the blood(大補氣血), invigorating the heart and nourishing blood(補心養血), dissipating phlegm and relieving mental stress(化痰寧神), regulating the spleen corresponds to earth(理脾土), invigorating the heart and the kidney(補心腎), reinforcing the liver and the kidney(培肝腎), promoting blood circulation to remove blood stasis(活血祛瘀) and etc. Herbal medication was followed as those method. The prescription was commonly used as Guibitang(歸脾湯), Insuksan(仁熟散), Chunwangbosimdan(天王補心丹), Susunghwan(壽星丸), Samjohwan(蔘棗丸) and etc.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.10
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• pp.1513-1520
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• 2014

The present aim was to investigate the effects of traditional Chinese medicine prescriptions (TCM) on body temperature, blood physiological parameters, nutrient apparent digestibility and growth performance of beef cattle under heat stress conditions. Twenty-seven beef cattle were randomly divided into three groups as following; i) high temperature control (HTC), ii) traditional Chinese medicine prescriptions I+high temperature (TCM I) and iii) traditional Chinese medicine prescriptions II+high temperature (TCM II) (n = 9 per group). The results showed that the mean body temperature declined in TCM II treatment (p<0.05). Serum $T_3$ and $T_4$ levels with TCM I and TCM II treatments elevated (p<0.05), and serum cortisol levels of TCM I treatments decreased (p<0.05), compared with the HTC group. Total protein, albumin, globulin in TCM II treatments elevated and blood urea nitrogen levels of both TCM treatments increased, but glucose levels of both TCM treatments decreased, compared with the HTC group (p<0.05). The apparent digestibility of organic matter and crude protein with TCM I treatment increased, and the apparent digestibility of acid detergent fiber elevated in both TCM treatments (p<0.05). Average daily feed intake was not different among three groups, however average daily gain increased and the feed:gain ratio decreased with both TCM treatments, compared with the HTC group (p<0.05). The present results suggest that dietary supplementation with TCM I or TCM II improves growth performance of heat stressed beef cattle by relieving heat stress responses and increasing nutrient apparent digestibility.

• Journal of Ginseng Research
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• v.47 no.6
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• pp.766-772
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• 2023

Background: Korean Red Ginseng (KRG) is an effective anti-stress treatment. In this study, we investigated the therapeutic potential effects of KRG on relieving stress in a general population using transcriptome analysis. Methods: We conducted an 8-week clinical pilot study on 90 healthy men who reported stress. The study was completed by 43 participants in the KRG group and 44 participants in the placebo group. Participants were randomized 1:1 to the KRG and placebo groups. We evaluated the stress by stress response inventory (SRI) at baseline and 8 weeks. The main outcomes were changes in the levels of neurotransmitters (NTs) and NT-related gene expression. NTs were analyzed using automated (GC) content, and levels of gene expression were measured by reads per kilobase of transcript per million mapped reads (RPKM). Results: The KRG group showed significantly preserved epinephrine decrease compared with placebo group at 8 weeks (changes in epinephrine, KRG vs. placebo; -1623.2 ± 46101.5 vs. -35116.3 ± 86288.2, p = 0012). Among subjects who higher SRI score, meaning stress increased compared to baseline, the KRG group showed a smaller decrease in serotonin than the placebo group (changes in serotonin, KRG vs. placebo; -2627.5 ± 5859.1 vs, -8087.4 ± 7162.4, p = 0.005) and a smaller increase in cortisol than the placebo group (changes in cortisol, KRG vs. placebo; 1912.7 ± 10097.75 vs. 8046.2 ± 8050.6 , p = 0.019) in subgroup analysis. Transcriptome findings indicated that KRG intake affects gene expression related with metabolism of choline, adrenalin, and monoamine. Conclusion: These findings suggest that KRG has beneficial effects on the amelioration of stress response in NTs, and this effect is more prominent in stressful situations. Further clinical studies are required to confirm the anti-stress effect of KRG.

• The Journal of Pediatrics of Korean Medicine
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• v.15 no.2
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• pp.141-165
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• 2001

Attention-deficit/hyperactivity disorder(ADHD) is one of the most common childhood-onset psychlatric disorders. It is distinguished by symptoms of inattention, hyperactivity, and impulsivity. ADHD may be accompanied by learning disabilities, depression, anxiety, conduct disorder, and oppositional defiant disorder. The etiology of ADHD is unknown, and the disorder may have several different causes. Individual with ADHD present in childhood and may continue to show symptoms as they enter adolescence and adult life. Public interest in ADHD has increased along with debate in the media concerning the diagnostic process and treatment strategies. The purpose of this study is oriental medical approach to ADHD. This study was progressed for oriental diagnosis and treatment for ADHD. In oriental medicine, the reason of ADHD was deficiency of the kidney, hyperactivity of the liver(腎虛肝亢), deficiency of the heart and the spleen(心脾不足), heart disturbed by phlegm and heat(痰熱擾心). The method of medical treatment was nourishing the kidney and checking exuberance of yang(滋腎潛陽), relieving mental stress and promoting wisdom(寧神益智), nourishing the heart and strengthening the spleen(養心健脾), tranquilzation(安神定志). removing heat-phlegm(淸熱化痰), inducing resuscitation and tranquilzation(開窮安神). The prescription was commonly used as Liuwei Dihuang Wan jiajian(六味地黃丸加減), Guipi Tang he Ganmai Dazao Tang jiajian(歸脾湯合甘麥大棗湯加減), Huanglian Wendan Tang jiawei(溫黃連溫膽湯加味). It should help primary care providers in their assessment of a common child health problem.