• Imaging Science in Dentistry
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• v.51 no.1
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• pp.1-7
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• 2021

Purpose: The aim of this study was to assess artifacts generated in cone-beam computed tomography (CBCT) of 3 types of dental implants using 3 metal artifact reduction (MAR) algorithm conditions (pre-acquisition MAR, post-acquisition MAR, and no MAR), and 2 peak kilovoltage (kVp) settings. Materials and Methods: Titanium-zirconium, titanium, and zirconium alloy implants were placed in a dry mandible. CBCT images were acquired using 84 and 90 kVp and at normal resolution for all 3 MAR conditions. The images were analyzed using ImageJ software (National Institutes of Health, Bethesda, MD) to calculate the intensity of artifacts for each combination of material and settings. A 3-factor analysis of variance model with up to 3-way interactions was used to determine whether there was a statistically significant difference in the mean intensity of artifacts associated with each factor. Results: The analysis of all 3 MAR conditions showed that using no MAR resulted in substantially more severe artifacts than either of the 2 MAR algorithms for the 3 implant materials; however, there were no significant differences between pre- and post-acquisition MAR. The 90 kVp setting generated less intense artifacts on average than the 84 kVp setting. The titanium-zirconium alloy generated significantly less intense artifacts than zirconium. Titanium generated artifacts at an intermediate level relative to the other 2 implant materials, but was not statistically significantly different from either. Conclusion: This in vitro study suggests that artifacts can be minimized by using a titanium-zirconium alloy at the 90 kVp setting, with either MAR setting.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.7
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• pp.823-832
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• 2007

This paper presents the static characteristics of EGR-WI combined system. The water injection system was statically characterized by recording the engine exhaust outlet $NO_x$ emissions for comparison with baseline $NO_x$ emissions. Effects of the water injection system on CO and HC emissions and fuel consumption were examined. The research engine used for these experiments was a 103 kW turbocharged, intercooled, 2.5 L VM Motori CIDI engine equipped with a cooled EGR system. Water injection in the intake system demonstrated the potential for significant reductions in engine outlet $NO_x$ emissions. The system has reduced engine outlet $NO_x$ emissions by 40-50%, but caused significant increases in CO and HC emissions, particularly at low loads. Fuel consumption effects were minimal.

• Proceedings of the Korea Concrete Institute Conference
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• 1990.10a
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• pp.79-82
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• 1990

The results of a large-scale study to determine the effects of epoxy coating on the bond strength between deformed reinforcement and concrete are descrebed. Tests include beam-end specimens containing No. 5(16mm), No. 6 (19mm), No. 8(25mm), No. 11(32mm) bars with average coating thicknesses ranging from 3 to 17 mils(0.08-0.43mm). Three deformation patterns are evaluated. Specimens with covers of 1, 2, and 3 bar deameters are studied. Both top-cast and bottom-cast bars are tested. Epoxy coatings are found to significantly reduce bond strength. The severity of that reduction is a function of deformation pattern, bar size, and coating thickness. Design recommendations based on these observations differ from the modifications to the 1989 ACI Building Code.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.5
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• pp.374-380
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• 2014

To estimate greenhouse gas (GHG) emission, the inventory of rice cultivation at the farming without agricultural chemicals was established from farmers in Gunsan, Jeonbuk province in 2011~2012. The objectives of this study were to calculate carbon footprint and analyse the major factor of GHGs. To do this, we carried out a sensitivity analysis using the analyzed main factors of GHGs and estimated the mitigation potential of GHGs. Also we suggested agricultural methods to reduce GHGs that can be appled by farmers at this region. At the farming system without agricultural chemicals, carbon footprint of rice production unit of 1 kg was 2.15 kg $CO_2.-eq.kg^{-1}$. Although the amount of carbon dioxide ($CO_2$) emission was the largest among GHGs, methane ($CH_4$) emission had the highest contribution to carbon footprint on rice production system when it was converted to carbon dioxide equivalent ($CO_2-eq.$) multiplied by the global warming potential (GWP). Main source of $CO_2$ emission in the rice farming system without agricultural chemicals was combustion of fossil fuels used by agricultural machinery. Most of the $CH_4$ was emitted during rice cultivation practice and its major emission factor was flooded paddy field in anaerobic condition. Also, most of the $N_2O$ was emitted from rice cultivation process. Major sources of the $N_2O$ emission was application of fertilizer such as compound fertilizer. As a result of sensitivity analysis in energy consumption, diesel had the highest sensitivity among the energy inputs. With the reduction of diesel consumption by 10%, it was estimated that $CO_2$ potential reduction was about 2.0%. With reducing application rate of compound fertilizer by 10%, the potential reduction was calculated that $CO_2$ and $N_2O$ could be reduced by 0.5% and 0.9%, respectively. At the condition of 10% reduction of silicate and compost, $CO_2$ and $CH_4$ could be reduced by 1.5% and 1.6%, respectively. With 8 days more drainage than the ordinary practice, $CH_4$ emission could be reduced by about 4.5%. Drainage and diesel consumption were the main sources having the largest effect on the GHG reduction at the farming system without agricultural chemicals. Based on the above results, we suggest that no-tillage and midsummer drainage could be a method to decrease GHG emissions from rice production system.

• Journal of Pharmacopuncture
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• v.5 no.2
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• pp.76-91
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• 2002

The lipid lowering and antioxidant effects of Gansoo(BL18), Pungji(GB20) and Eumnungcheun(SP9) acupuncture in rats fed high fat diet were analyzed in biochemical and molecular biological aspects. The results obtained from this study are as follows : 1. In the body weight reduction, all acupuncture groups showed a high reduction compared to those of control group and in acupuncture groups, Gansoo(BL18) and Pungji(GB20) acupuncture groups showed a high reduction. 2. The concentration of plasma triglyceride, total cholesterol and LDL-cholesterol with acupuncture groups showed a little decrease and in acupuncture groups, Gansoo(BL18) and Pungji(GB20) groups showed a low values compared to those of other acupuncture groups. However, the tendency of HDL-cholesterol concentration showed no significant different. 3. The concentration of plasma ${\beta}-lipoprotein$ and free fatty acids showed a lowest values in the Gansoo(BL18) and Pungji(GB20) acupuncture groups and the glucose concentration showed to decrease in all treated acupuncture groups. 4. The concentration of liver total cholesterol and triglyceride in Gansoo(BL18) and Pungji(GB20) acupuncture groups showed a lower values than those of control group. 5. In all the acupuncture groups, the plasma glutamic oxaloacetic transaminase(GOT) activity showed a little decrease. In the glutamic pyruvate activity(GPT), Gansoo(BL18) and Pungji(GB20) acupuncture groups showed a lower values than those of control groups. However the values of eumneungcheun acupuncture only group showed no significant difference to those of control group. 6. The plasma and liver Thiobabituric acid reactive substance (TBARS) concentration in Gansoo(BL18) and Pungji(GB20) acupuncture groups were a lower than those of control group. However the values of eumneungcheun acupuncture group showed no significant difference to control group. 7. The superoxide dismutase (SOD) activity in Gansoo(BL18) acupuncture group and Glutathione peroxidase (GSH-Px) activity in Gansoo(BL18) and Pungji(GB20) acupuncture groups showed a high values. The catalase (CAT) activity in all the acupuncture groups showed a higher values than those of control group. 8. In acupuncture groups, DNA expression of Apo-B and Apo-E showed a tendency to decrease, however DNA expression of leptin showed no significant difference in all treatment groups. DNA expression of $TNF-{\alpha}$ showed a increase in acupuncture groups. These results indicate that Gansoo(BL18) and Pungji(GB20) (especially Gansoo(BL18)) acupuncture affect the lipid metabolism and showed possibility of lowering adipose tissue mass and lipid peroxidation.

• Journal of Korean Biological Nursing Science
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• v.9 no.2
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• pp.118-124
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• 2007

Purpose: The purpose of this study was to compare three surgical scrub methods-4% chlorhexidine gluconate(CHG) with brush, 4% CHG without brush, and waterless scrub using 1% CHG and 61% ethanol combination(alcohol-based agent)-for antimicrobial efficacy. Method: "Glove-juice technique" was used to evaluate microbial hand counts before surgical scrubs, 1 min and 3 hr after surgical scrubs. Result: Waterless scrub using CHG and ethanol combination resulted in a 4.8-log reduction at 1 min and 4.0-log reduction at 3 hr. CHG without brush resulted in a 4.7-log reduction at 1 min and 3.3-log reduction at 3 hr. The traditional scrub using CHG with brush resulted in a 3.6-log reduction at 1 min and 0.8-log reduction at 3 hr. The waterless scrub and CHG without brush showed significantly higher log reduction(p<.05) than CHG with brush at 1 min and 3 hr after surgical scrub. Waterless scrub showed greater log reductions than CHG without brush, but there was no statistical difference between the two groups. Conclusion: Waterless scrub using alcohol-based agent showed more persistent and immediate antimicrobial efficacy than either CHG with brush or CHG without brush.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.677-683
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• 2001

The object of this study is in the comparison of level of depression between patients with chronic low back pain & normal adult, of the relation between reduction of pain & level of depression and in the examination of the influence of traditional physical therapy against the reduction of pain & level of depression of the patients with chronic low back pain for the new recognition of psychological factors to the physical therapists as well as patients. This study was targeted for 40 patients with chronic low back pain who were diagnosed as lumbar sprain & herniated intervertebral disk and compared & analyzed how traditional physical therapy has an influence to their reduction of pain and level of depression by questioning with visual an analog scale of Beck's depression inventory & pain inventory to them. The results are as follows. 1. Traditional physical therapy has an effect in the reduction of pain of the patients with chronic low back pain. 2. Although traditional physical therapy relieved a little the level of depression of patients with chronic low back pain. there was no evident effect statistically. 3. In the relation between the reduction of pain and level of depression, level of depression also showed somewhat relief according to the reduction of pain and appeared that they have some relationship. However, it's degree was not big. 4. In the comparison of the level of depression between the normal adult and the patient with chronic low back pain, the level of depression of the patient with low back pain are high rather than that of normal adult.

• Journal of the Korean Society of Safety
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• v.33 no.2
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• pp.145-151
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• 2018

In this study, the track-bridge interaction analysis was performed using an analytical model considering the track structure, thereby taking into account the linear conditions (R=650 m, cant variation $160{\pm}60mm$) and the dynamic characteristics of the bridge. As a result of the study, the allowable speed on the example bridge considered was calculated at 200 km/h based on vertical deflection, vertical acceleration, and irregularity in longitudinal level, but was also evaluated at 170km/h based on the coefficient of derailment, wheel load reduction, and lateral displacement of the rail head. It is considered desirable to set the speed 170km/h to the speed limit in order to secure the safety of both the bridge and the track. It is judged that there will be no problems with ensuring rail protection and train stability in the speed band.

• Smart Structures and Systems
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• v.11 no.2
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• pp.163-183
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• 2013

Control systems have been greatly studied in recent years and can be classified as: passive, active, semi-active or hybrid systems. Most forms of control systems have been applied in a centralized manner where all the information is sent to a central node where control the algorithm is then calculated. One of the possible problems of centralized control is the difficulty to scale its application. In this paper, a completely decentralized control algorithm is analytically implemented. The algorithm considers that each of the control systems makes the best decision based solely on the information collected at its location. Semi-active control is used in preference to active control because it has minimal energy consumption, little to no possibility of destabilization, a reduction in the possibility of data saturation, and a reduction in the response time in comparison to centralized control.

• Child Health Nursing Research
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• v.12 no.2
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• pp.215-222
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• 2006

Purpose: This study was done to identify the effects of the distraction generated by character stamp and stickers on reduction of intravenous injection pain. Method: This study was conducted using a quasi experimental non-equivalent control group non-synchronized design. 60 preschool children who admitted to a Pediatric Department in a C University Hospital were selected as subjects. Convenience assignment was used. The two groups were homogeneous on characteristics. Results: In the experimental group, objective pain(t=3.666, p=.001), subjective pain (t=3.415, p=.001) and perceived pain by the mother(t=2.528, p=0.014) decreased after intravenous injections than the control group. There were no statistical significant differences in pulse rate or fear between the experimental and the control group.　Conclusion: These findings indicate that using character stamp and stickers could be considered as an independent nursing intervention for intravenous injection pain reduction in preschooler.