• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.497-503
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• 2001

Evidence from the last 10 years have been suggested that melatonin mainly produce a depressant effect on the cardiac system, but we found an activating effect of melatonin on heart rate in this research. To determine the hypothesis that melatonin has dual effects on physiological behaviour of cardiac system, we investigated the effects of melatonin on heart rate in isolated rat atria and anesthetized rats. Regardless of concentration, melatonin produced bradycardia in the 84 cases of 148 experiments (57 %) and tachycardia in the 64 cases of 148 experiments (43 %). And in atrium, melatonin produced a decrease automaticity in 52 cases of 86 experiments (60 %) and increase automaticity in 40 % (34/86 cases). Also, these effects are not significnat relationship with concetration of melatonin. The melatonin-induced bradycardia in vivo was inhibited by pretreatment of atropine or bilateral cervical vagotomy. Also, in isolated atrium the melatonin-induced decrease in automaticity was inhibited by pretreatment of atropine. These melatonin-induced responses were potenitated by pretreatment of propranolol. The melatonin-induced tachycardia in vivo was inhibited by pretreatment of propranolol, nifedipine or bilateral cervical vagotomy, but not by pretreatment of atropine. The melatonin-induced incease in automaticity in isolated atrium was converted to decrease in automaticity by pretreatment of propranolol. In addition, the change in heart rate caused by adrenoceptor agonists was inhibited by pretreatment of melatonin. These results indicate that melatonin-induced bradycardia may be related to a muscarinic receptor activation and melatonin-induced tachycardia may be related to a $\beta$-adrenoceptor stimulation.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.825-839
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• 2010

The global and domestic market for offshore wind farm is expected to grow fast, and the design and installation of substructure and foundation is getting more important. As for the offshore wind farms located in the shallow(depth < 20m) water, the construction and installation of the substructure and foundation makes up about 1/4 ~1/3 of the offshore wind farm construction cost, and the portion is expected to increase because the turbine capacity is increasing from 2 ~ 3MW to 5MW or larger and the water depth of wind farms is also increasing over 30m. As a foundation for offshore wind turbine, the suction caisson foundation is being considered to be a highly competitive alternative to the conventional monopile or gravity based structure, because it has features suitable for the offshore construction such as quick installation, no heavy equipment for penetration and no hammering noise for driving. In order to study the installation behaviour of the suction caisson, laboratory tests were performed with sand. The pore water pressure and displacement were measured to analyze the suction pressure during penetration, the penetration speed and the amount of heaving.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.3
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• pp.148-154
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• 2018

When shooting small arms, the inner surface temperature is heated up to about $700{\sim}1,000^{\circ}C$ by the friction of the bullet and the inner wall of the barrel and the combustion of propellant. High-temperature propellant gas and high-speed movement of the bullet cause corrosion of the inner wall, which is noticeable immediately in front of the chamber. In this study, the mechanical properties of Cr-Mo-V steel, which is the base material, were tested using Taguchi experimental design to find the best nitriding treatment conditions. For the nitriding process, the working time, salt bath temperature, and salt concentration were combined as three conditions and placed in the $L_9(3^4)$, orthogonal array table. The thicknesses of the white layer and the nitrogen diffusion layer were measured after nitriding under each condition in a salt bath furnace. Durability was evaluated by measuring the degree of dispersion through actual shooting because it was difficult to evaluate the mechanical properties of the cylinder inner structure. As a result, it was confirmed that the durability was optimal at $565^{\circ}C$, 1 hour, 0.5%. These optimal conditions were selected by the statistical analysis of the Minitab program(ver.17).

• Korean Journal of Plant Resources
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• v.33 no.3
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• pp.194-199
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• 2020

This study was carried out to get the information of Plum tree (192 germplasm) collected in Korea, and to evaluate the organic acid contents and fermentation solution. The organic acid content of fruit was 50.9 ± 6.0 mg/g, and which was composed of 55.5% of citric acid, 43.4% of malic acid and 1.1% of oxalic acid, and showed large difference among germplasms. Oxalic acid and malic acid made no differences in organic acid content according to flesh color, whereas citric acid and total organic acid contents were highest in orange color and lowest in whitish green. Malic acid, citric acid and total organic acid contents did not show differences among fruit weight groups, but oxalic acid content was highest at fruit weight of 5.1 ~ 10.0 g and lowest at more than 20.1 g. The sugar content of fermentation solution of fruit was 55.7 ± 1.6 °Brix and the harvest rate was 116.7 ± 8.7%. The correlation coefficients among fruit weight, the sugar content (°Brix) and harvest rate of fermentation solution were very low, and there were correlations of r=-0.551^⁎⁎ between fruit weight and oxalic acid, r=-0.767^⁎⁎ between malic acid and citric acid, and r=0.834^⁎⁎ between citric acid and total organic acid content.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.5
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• pp.367-371
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• 2009

Purpose: The purpose of this study was to evaluate the feasibility of the outfracture osteotomy sinus graft technique with the evaluation of 5-year survival rate of the implants placed in the atrophic edentulous posterior maxillary area. Materials and methods: One hundred and thirteen cases of 96 patients who visited our center from Aug 2004 to July 2009 and were diagnosed as atrophic edentulous maxillary alveolar ridge, were selected and underwent augmentation sinus surgery with outfracture osteotomy technique. Feasibility of the outfracture osteotomy technique was investigated with clinical and radiographic evaluation to assess the survival rate of the total dental implants in augmentation sinus surgery of this new kind. Total fixture number available in follow-up period was 179, in which the lost 10 patients were excluded out of 96 patients. Results: Five-year cumulative survival rate was 97.2% with 5 failures of total 179 fixtures. The average follow-up period was 29 and a half months, with the minimum and maximum follow-up periods of 4 months 21 days and 59 months 14 days, respectively. Conclusion: Traditional infracture technique is a popular method for an augmentation sinus surgery. The authors modified this classical method by outfracturing and readapting the bony window after sinus graft, with excellent treatment results evidenced by high survival rate of 97.2% (174 out of 179 fixtures), which proves the feasibility of the newly-designed outfracture osteotomy sinus graft technique.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.4
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• pp.203-212
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• 2013

Objectives This study was to investigate the correlation of low back pain, stress by event, and fear-avoidance beliefs caused by traffic accident. Methods We investigated 103 cases of out-patient with traffic accident. The patients answered that Visual Analogue Scale (VAS), Impact of Event Scale Revised Korean Version (IES-R-K), and Fear-Avoidance Beliefs Questionnaire (FABQ) on the first medical examination. We calculated statistical significance with this data. Results VAS, IES-R-K, and FABQ scores of the female patients with the traffic accident were higher than the male patients. VAS, IES-R-K, and FABQ scores showed low significant positive correlation and showed partial correlation between IES-R-K and FABQ, controlled by VAS, had no statistical significance in this research. Conclusions More considerations on pain, stress by event, and fear avoidance belief should be needed in treatment of the traffic accident patients.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.4
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• pp.129-141
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• 2013

Objectives The aim of this review is to investigate clinical studies for manual therapy on Temporomandibular Joint Disorder and to propose for the better method of studies in the future. Methods We investigated recent clinical studies for manual therapy on Temporomandibular Joint Disorder via searching Pubmed, KISS, KISTI, KERIS, KMBASE and National Assembly Library. 21 domestic and overseas articles were analyzed and the journals, the authors, the published years, countries, methods, periods, techniques of chiropractic, outcome measures, and purpose of those articles were examined. Results Studies on manual therapy were mainly published via Cranio. The diagnostic criteria that most frequently adopted in the overseas articles were research diagnostic criteria for temporomandibular disorders, The technique of chiropractic that most frequently adopted in the articles was passive traction and translation of TMJ. Many of the studies were researched for effectiveness of the manual therapy as the secondary treatment. Conclusions Reviewing the recent clinical studies for manual therapy on temporomandibular joint disorder and figuring out the strong points and weak points of those studies are necessary to future studies. It is anticipated that this review would benefit the in-depth treatments for temporomandibular joint disorder in terms of Korean medicine.

• Fashion & Textile Research Journal
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• v.4 no.2
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• pp.137-144
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• 2002

This study was to provide the fundamental data for a scientific and rational clothing construction by investigating the variation of the upper body surface with the use of the method of Surgical tape. The subject were 3 middle elementary schoolboys classified standard somatotype, and arm-movements were consisted of 6 types. The statistical analyses used in this study were mean, standard deviation and the ANOVA and LSD procedure. Shoulder point was moved to be the inside or upside and the shape of the armhole-line was differently changed as the arm-movement become larger. By moving to upside of the anterior armpit point, posterior armpit point and armpit point, the increase of the side seam length and the ascent of the line of width between armpits were distinct. And by arm-movements, in the items of horizontal, front neck base girth, back upper bust girth, back bust girth and back waist girth were increased and the other standard lines were apt to be decreased. In the items of vertical, all standard lines of front side and side seam length showed increased, back waist length and back length showed decreased. The variation of armhole was indefinite. In the rate of the variation, the shoulder length showed the maximum rate of contraction by 41.3%, decreasing 3.7 cm in $180^{\circ}$ degrees, and the side seam length showed the maximum rate of expansion by 60.6%, increasing 8.97 cm in the same degrees.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.737-750
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• 2018

Effects of acid soaking (AS) and thermal sterilization (TS) on the shape and quality characteristics of Tteokbokki rice cake (TRC) were investigated. The F-value of a sequential process (SP) of the combination of AS and TS was quantitatively determined with a reference microorganism of Bacillus cereus. F-values were evaluated according to the minimum and the maximum D-value of B. cereus and the reduction exponent (m=12). The heat penetration curves at cold point (CP) of TRC (400 g) were used to estimate the TS time at 121, 100, and $95^{\circ}C$. F-values of the SP were revised according to the adjusted m values after AS at different pH. The non-uniformity parameters (NUP) of TRC had no significant changes during AS but it dramatically increased after applying TS at a low pH by AS. The result of solubilized starch contents (SSC) demonstrated that the shape changes during SP are related to SSC. The texture characteristics and the whiteness were significantly influenced by a low pH condition (3.5) (p<0.05). Sensory analysis showed that a lower pH and a longer thermal processing time influenced negatively on the acceptability. This study showed that pH 4.0 and $95^{\circ}C$ was an optimum condition for the SP.

• Korean Journal of Ichthyology
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• v.7 no.2
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• pp.160-170
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• 1995

The authors investigated feeding habit of river sculpin(C. poecilopus) were conducted at the Chiak streams from April 1993 to March 1994. The feeding habit of C. poecilopus was mainly acquatic insects, such as Ephemeroptera, Odonata, Plecoptera, Trichoptera, Coleoptera, Diptera, and Nematoda, teleost fishes, fish egg and terrestrial insects. Terrestrial insects in the stomach contents were found mainly in autumn, and teleost fish(Moroco oxycephalus) was in summer. Aquatic insects(Ephemeroptera, Trichoptera and Diptera) constituted the bulk of food items ingested during each season. The prey selection indices for Ephemeroptera were positively selected in summer, and negatively selected in autumn and winter, Tricoptera and Diptera were positively selected in autumn and winter, and negatively selected in summer. Additionally, analysis for stomach contents of guarding males suggests that the parental males eat their own eggs during egg guarding(filial-cannibalism).