• The korean journal of orthodontics
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• v.31 no.1 s.84
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• pp.15-24
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• 2001

In order to achieve a desirable tooth movement, it is of great importance to control the M/F ratio and to know the location of the center of resistance. The purpose of this study was to locate the center of resistance and the axis of rotation, and to estimate the stress distribution in the periodontal ligament with experimental model. After preparing a model of an upper canine with a simulated periodontal ligament and alveolar bone, the force and moment were applied. The tooth movement was traced using measuring device with LVDTs(Linear variable differential transformers) that can measure three dimensional tooth movement in real time. The results were as follows. 1. The location of center of resistance by transverse force was $29\%$ of root length measured from alveolar crest to apex regardless of force magnitude. The position of the center of resistance is more coronal than that of two-dimensional model($42\%$). 2. The center of resistance and the axis of rotation coincide when couple moment was applied. 3. As the magnitude of moment increases, tooth tends to extrude irrespective of the direction of the moment. 4. The relationship between location of force and axis of rotation (a x b = $49.6\;mm^2$) was obtained. A tooth movement can be predicted through this formula. 5. The centers of rotation by transverse force were plotted linearly.

• Journal of the Korean Home Economics Association
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• v.20 no.4
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• pp.155-168
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• 1982

What is attempted here is to find out an optimum method for the design of physical environments that could save human energy expenditures and safely perform household duties. There are, if any, very little amount of research done in this area. This is particulary so when the work relates to the designing of household storage facilities in the light of the energy metabolism of human body. The first step to this study, therefore, is to find out the ways by which we can determine the energy metabolism of human body accurately. To measure the volume and the concentration of human respiration continuously and automatically, a new apparatus is selected here. This includes the recording system with the Wright Respirometer and the Expired Gas Analyzer as well as the computer system to multiply volume by concentration of human respiration and to integrate them for a given time. Then, the author experimented on the reliability of this apparatus and came to the conclusion that this apparatus satisfied our need to research the energy metabolism of human body. Next, the general plan and procedures to experiment with this apparatus have been determined as follows: 1) subjects are three young and sound females. Their physical characteristics are shown in Table 1 and most approximates the standard characteristics of Japanese females, 2) height of open shelves is selected in such away as to correspond to the respective height of each subject(see Table 2), 3) utensils to be stored are box shaped object, which weight is 0.5kg, 1.0kg, 2.0kg or 3.0kg, 4) working motions are given while one or two hands as to place utensil on each shelf from the standard working board, 85 cm in height and then to place back it on the board from the shelf and repeated in constant velocity as 10 times per a minute, 5) each posture of motion is chosen by each subject in free, 6) procedures of measurement of human energy metabolism ard shown at(6), 1, Section 3 as specific methods for using this apparatus. Findings of this study are as follows: 1. Human energy expenditures for storing utensils on shelves by each subject are shown in quantity more accurately than in any other studies, under varying conditions about height of shelves, load of utensils and working motion with one hand and two hands (see Fig. 8~13 and Table 3). 2. Experimental formulae of human energy expenditure for that work are shown as formula (8), (9) and (10), to generalize results of 1. and to apply those for working motion under given conditions. 3. As results of analysis on gained data, we are able to show the standard model of human energy expenditures for storing untensils on shelves by the standard Japanese female (see Table 7 and Fig. 14).

• Journal of Society of Preventive Korean Medicine
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• v.6 no.2
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• pp.112-127
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• 2002

Objectives: Younnyeniksoobulrodan(延年益壽不老丹) composed of Polygonum multiflorum THUNB. and some medical herbs is known as formula of senescence delay effect. The purpose of this study is to investigate the effect of Younnyeniksoobulrodan(延年益壽不老丹) on antioxidant enzyme activity such as Thiobarbituric acid reactive substance(TBARS), Superoxide dismutase(SOD), Catalase(CAT), Glutathione peroxidase (GSH-px) in rat erythrocytes and liver. Methods: Sprague-Dawley rats divided into 4 gorups, Young group(8 weeks old, N-8), Aging group(18 weeks old, N-18), pathologically induced aging gorup(injected D-galatose 50mg／kg, 1time／day for 6 weeks, CON) and Younnyeniksoobulrodan(延年益壽不老丹) administered group(D-galactose 50mg／kg and Younnyeniksoobulrodan extracts 840.0mg／kg 1time／day for 6 weeks, YIB). Rats were sacrificed and TBARS, SOD, CAT, and GSH-px were measured in rat erythrocytes and liver. Results: Plasma and liver TBARS concentrations of YIB group were significantly lower than those of control. Red blood cell(RBC) SOD activities of YIB group was increased(F=3.445, p=0.033, ANOVA test), and RBC catalase activities of all experimental group were not significantly different. RBC GSH-px activities of YIB group was increased(F=9.365,p=0.0001, ANOVA test). Liver SOD activities of YIB group was higher than those of control(F=4.967, p=0.008, ANOVA test). Liver catalase activities of all experimental group were not significantly different, and liver GSH-px activity of YIB group was significantly higher than that of control(F=3.846, p=0.022,ANOVA test). Conclusions: According to the above results, it is considered that Younnyeniksoobulrodan is effective in inhibiting lipid peroxidation and increasing antioxidative enzyme activities in D-galactose induced aging rat.

• The Journal of Engineering Geology
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• v.6 no.3
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• pp.155-163
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• 1996

The current ASTM C227-90 is a prescription on the mortar-bar method. This recornrnends that mortar-bars should be made using a mixing ratio by weight of 675 grams aggregate to 300 grams cement, and their initial lengths should be measured in $24{\pm}2$ hours. This method emphasizes that the prepare sample mortar-bars and calculate expansion rates of them. This method requires constant G values (effective gauge lengths) of denominator in the calculation formula, which are fixed either at 10 inches or 250mm. This study, based on experimental approaches, reexamines the suggestions made by those two prescriptions above and important results are summarized in the following. 1. Not only alkali-aggregate reaction but also interaction of interstitial and gel water are responsible for expansion of mortar-bars. This requires partial modification of the current ASTM C227-90. 2. A mixing ratio by volume rather than by weight of aggregate to cement is recommendable for measuring the amount of expansion resulting from alkali-aggregate reaction and from interstitial water. 3. The method of when to measure initial lengths and how to calculate expansion rate suggested by ASThI C227-90 and Cl90-93a should partly be modified for more accurate results.

• Journal of Korean Society of Disaster and Security
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• v.11 no.1
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• pp.31-38
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• 2018

The 99.1% of small dam and most of the levees in Korea are soil dam which can be constructed with lower cost and less effort compared with ones made of concrete. However, they are so vulnerable to overflow. Sudden collapses of these strucrues lead to increase flow rate rapidly, which may cause catastrophic problems in downstream regions. In this study, the experimental study on the collapse delay effect of riprap that was laid on slope of soil levee was carried out. A prismatic rectangular open channel was used and three different sizes of the riprap were installed on slope of a scaled earth dam. A new formula for the collapse time of the levee with the installation of riprap was presented, using the previous researches and the dimensional analysis. In this process, an unsteady flow condition was considered to derive the deviation time of the riprap. And additional experiments were conducted to understand the effect of reinforcement of riprap, and it was found that the reinforcement of riprap was more effective than twice sizing of intial riprap. If the collapse time is delayed, EAP (Emergency Action Plan) and forecasting can greatly reduce the degree of flood damage. Also, it will be meaningful that the results of this study are used for river design.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.148-156
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• 2020

The paper is a summary of the results of the basic pullout test which is conducted to evaluate the anchorage capacity of high strength headed bars that is mechanical anchored vertically on steel fiber reinforced concrete members. The main experimental parameters are volume fraction of steel fiber, concrete strength, anchorage length, yield strength of headed bars, and shear reinforcement bar. Both sides of covering depth of the specimen are planned to double the diameter of the headed bars. The hinged point is placed at the position of each 1.5𝑙_dt and 0.7𝑙_dt around the headed bars, and the headed bars are drawn directly. As a result of pullout test experiment, concrete fracture and steel tensile rupture appear by experimental parameters. The compressive strength of concrete is 2.7~5.4% higher than that of steel fiber with the same parameters, while the pullout strength is 20.9~63.1% higher than that of steel fiber without the same parameters, which is evaluated to contribute greatly to the improvement of the anchorage capacity. The reinforcements of shear reinforcements parallel to the headed bars increased 1.7~7.7% pullout strength for steel fiber reinforced concrete, but the effect on the improvement of the anchorage capacity was not significant considering the increase in concrete strength. As with the details of this experiment, it is believed that the design formula for the anchorage length of KCI2017and KCI2012 are suitable for the mechanical development design of SD600 head bar that is perpendicular to the steel fiber reinforced concrete members.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.4
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• pp.377-386
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• 2021

In dense cities, which are covered by many impermeable areas, rainwater flows quickly along the roads and collects in certain areas. The surface runoff that fails to get intercepted by the roadside rain gutters results in a wider flow of water along the sides, which in turn increases the amount of water on the road and causes traffic congestion as well as accidents due to slippage. Based on these issues, this study was carried out in order to propose an intercepted flow calculation formula. To this end, the maximum longitudinal slopes of arterial roads and expressways were reflected to depict a road condition of 2~10 %, while a general traverse slope of 2 % was selected for the traverse slope on the side. As for the road lane condition, two, three, and four lanes were chosen for the area from the centerline to the sidewalk. As for the experimental flow rate, the rainwater runoffs at the actual design frequency of 5, 10, 20, and 30 years for road conditions were converted into experimental flow rates, and as a result, flow rates ranging from 1.36 l/s to 3.96 l/s were divided into ten flow rates for a hydraulic experiment. Also, an equation taking into consideration the inflow velocity and flow width along the roadsides was proposed. The results of the experiment showed an increase in flow width and a decrease in interception rate. Also, the inflow velocity at a traverse slope of 2 % was measured, while increasing the longitudinal slope. Accordingly, an equation for calculating the flow intercepted by rain gutters at a flow width reflecting the longitudinal slope of the road and rainwater runoff, according to the design frequency, was derived by performing a regression analysis using IBM SPSS Statistics 24. It is deemed that the equation derived in this study will be useful in designing rain gutters for roads.

• The Korea Journal of Herbology
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• v.36 no.5
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• pp.15-27
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• 2021

Objectives : The processing of Pinelliae Tuber and Arisaematis Rhizoma is a crucial step to reduce the severe acrid irritation mainly due to the needle-like crystals (raphides). Ginger, alum and bile juice have been used as adjuvant materials for the processing. Methods : Bibliographic research on ancient processing and experimental processing was performed to investigate the toxicity reduction mechanisms of the processing with ginger, alum and bile juice. Results : Ginger has been a major adjuvant for the processing of Pinelliae Tuber, followed by alum and bile juice since Song (宋) and Myeong (明) dynasties, and Arisaematis Rhizoma has been mainly used as Damnamseong (膽南星). The raphides consisting of calcium oxalate, lectin, agglutinin and polysaccharides can induce acrid irritation and the inflammatory reactions. The lipophilic components in the ginger denatured the structure of raphides and 6-gingerol-contained ginger extract attenuated the inflammatory reaction. The calcium ion (Ca²⁺) of calcium oxalate was substituted to the aluminium ion (Al³⁺) of the alum, which damaged the calcium oxalate structure. Lectin attached to the surface of raphides was dissolved in alum solution and consequently its structure was denatured. The cholate in the bile juice formed the complex with the oxalate anion or the calcium cation. Moreover, the enzymes activated by Lactobacillus or Bifidobacterium during the fermentation promoted the fragmentation of oxalate. Conclusion : The adjuvant materials damaged the raphides by denaturing or degrading the calcium oxalate, resulting in the reduction of acrid irritation. Further experimental studies would support the toxicity reduction mechanism of the processing.

• The Journal of Korean Obstetrics and Gynecology
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• v.34 no.3
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• pp.29-48
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• 2021

Objectives: Banchong-san (BCS) is a herbal formula composed of 13 korean medicinal herbs and is traditionally used to treat inflammatory diseases and pain. The object of this study was to research the antioxidant, anti-inflammatory, antipruritic and antimicrobial effects of the BCS in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Methods: In this experiment, effects of BCS on the following four were measured as follows: (1) Anti-oxidative effects were evaluated by 1,1-diphenyl-2-picryl-hydrazyl (DPPH) Radical scavenging activity, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) Radical scavenging activity. (2) Anti-inflammatory effects were evaluated by the production amount of Reactive oxygen species (ROS), Nitric oxide (NO), Interleukin-1β (IL-1β), Interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), Prostaglandin E2 (PGE₂), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2)(the previous two are "mRNA"), extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinases (p38), inhibitor of nuclear factor kappa B (IκBα), nuclear factor kappa B (NF-κB) (the previous five are "Protein") in LPS-Stimulated RAW 264.7 cells. (3)Antipruritic effects were evaluated by the production amount of histamine, Leukotriene B4 (LTB4), LeukotrieneC4 (LTC4) Levels in phorbol 12-myristate 13-acetate(PMA)/ionomycin-stimulated MC/9 mast cell. (4) Anti-microbial effects were evaluated by the growth suppression of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Aspergillus niger. Results: The following results were obtained through each measurement: (1) DPPH Radical Scavenging Activity, ABTS Radical Scavenging Activity evoked a significant concentration-dependent increase. (2) ROS, NO, IL-1β, IL-6, TNF-α, PGE₂ production amount, iNOS, COX-2 mRNA expression were significantly reduced in the BCS extraction group compared with the control group and significantly decreased the amount of ERK, JNK, p38, NF-κB Protein expression. The amount of IκB-α Protein Expression have increased significantly. (3) The amounts of histamine, LTB4, LTC4 were significantly decreased. (4) The antibacterial efficacy, BCS inhibited the growth of Escherichia coli, Pseudomonas aeruginosa at concentrations of 5 ㎍/ml, but did not suppress the growth of staphylococcus aureus and aspergillus niger. Conclusions: The experimental results show that BCS has anti-oxidant, anti-inflammatory, antipruritic and antimicrobial properties.

• The Journal of Korean Obstetrics and Gynecology
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• v.36 no.3
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• pp.1-24
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• 2023

Objectives: Boeum-jeon (BEJ) is a herbal formula composed 8 Korean medicinal herbs and is traditionally used to treat inflammatory diseases. In this study, the authors tried to confirm the antioxidant efficacy of BEJ and its anti-inflammatory effect in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Methods: In this experiment, results of BEJ on the following two were measured as follows: (1) Antioxidant effects was measured by DPPH Radical scavenging Activity, ABTS Radical scavenging Activity. (2) Anti-Inflammatory effects were evaluated by the production amount of ROS, NO, Cytokine (PGE2, IL-1β, IL-6, TNF-α), COX-2, iNOS, TNF-α, IL-1β, IL-6, HO-1, NQO1 (the previous seven are "mRNA Expression"), COX-2, iNOS, TNF-α, IL-1β, IL-6, HO-1, NQO1, NRF2 (the previous eight are "Protein Expression") ERK, JNK, p38 (the previous three are "Protein Phosphorylation") in LPS-stimulated RAW 264.7 cells. Results: The experimental measurement results are as follows: (1) DPPH Radical scavenging Activity, ABTS Radical scavenging Activity increased in a concentration -dependent manner in the BEJ-treated group. (2) As a result of measuring anti-inflammatory efficacy, the production of ROS, NO, and Cytokine (PGE2, TNF-α, IL-1β, IL-6) in the BEJ-administered group was significantly reduced compared to the control group. (3) Among mRNA Expression levels, COX-2, iNOS, IL-1β, IL-6 and TNF-α was significantly decreased in a concentration-dependent manner than in the control group, and HO-1 and NQO1 were significantly increased in a concentration -dependent manner than in the control group. (4) Among the Protein Expression levels, COX-2, iNOS, IL-1β, IL-6 and TNF-α was significantly decreased in a concentration -dependent manner compared to the control group, and HO-1, NQO1 and NRF2 was significantly increased in a concentration-dependent manner compared to the control group. (5) As a result of Protein Phosphorylation, ERK, p38 and JNK was significantly decreased compared to the control group in a concentration-dependent manner. Conclusions: Boeum-jeon has been experimentally confirmed to have antioxidant and anti-inflammatory effects, and if the evidence for efficacy is reinforced through further studies such as in vivo studies and clinical trials in the future, it can be effectively used to treat various inflammatory diseases such as bladder inflammation and chronic pelvic inflammation.