• Journal of Korean Medicine Rehabilitation
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• v.18 no.1
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• pp.173-185
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• 2008

Objectives : The purpose of this study was to observe the effect of Bong (a type of stick which is called bong) Chuna manual therapy (CMT) on the correction of posterior inferior (PI) ilium deviation, and evaluate changes of pain intensity and Oswestry Disability Index (ODI) for the treatment of low back pain. Methods : We measured leg length inequality (LLI), as an indicator of correction of PI ilium, before and after the Bong CMT twice immediately, and also checked the change of LLI in the course of 10 times of treatment. Ten times of Bong CMT with oriental medical treatment, such as acupuncture and bee venom pharmacopuncture, were performed not only to correct the PI ilium deviation but also to alleviate pain. Visual Analog Scale (VAS) and Oswetry Low-back Pain Disability Index (ODI) score were scored to evaluate the pain and function of low back. Results : In this study, LLI was decreased in general while we performed correction of PI ilium deviation immediately, also effectively decreased comparing between before and after 10 times of Bong CMT, Bong CMT with oriental medical treatment improved pain and function of low back. Conclusions : These results suggest that Bong CMT may be an effective method for the correction of PI ilium deviation. However more rigorous study should be followed because of small cases report.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.537-546
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• 1994

The physical characteristics of polymer modified asphalt depend on many parameters, such as, the polymer nature, polymer content and the asphalt properties. The objective of this study is to investigate the temperature susceptibility of polymer modified asphalt. The asphalts employed in this study were two different grades : a soft(200/300) grade and a hard(85/100) grade. And chlorinated polyethylene of two different characteristics were used : plastomer(Tyrin 2552) and elastomer(Tyrin CM0730). Temperature susceptibility of asphalt is a fundamental feature for characterizing asphalt and modified asphalt. It can be quantified by the penetration index(PI) and pen-vis number(PVN). These indices were obtained from the measurements of penetration and viscosity of the asphalt samples. For both of asphalts, the addition of the polymers increases the value of PI and PVN. Plastomer modified asphalt shows higher value of PI and PVN than elastomer modified asphalt. Soft grade shows more temperature susceptibility than hard grade at elevated temperatures.

• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.6
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• pp.141-150
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• 2021

In order to assess the impact of climate change on irrigation reservoirs, climate exposure (EI), sensitivity (SI), and potential impact (PI) were evaluated for 1,651 reservoirs nationwide. Climate exposure and sensitivity by each reservoir were calculated using data collected from 2011 to 2020 for seven proxy variables (e.g. annual rainfall) and six proxy variables (e.g. irrigation days), respectively. The potential impact was calculated as the weighted sum of climate exposure and sensitivity, and was classified into four levels: 'Low (PI<0.4)', 'Medium (PI<0.6)', 'High (PI<0.8)', and 'Critical (PI≥0.8)'. The result showed that both the climate exposure index and the sensitivity index were on average high in Daegu and Gyeongbuk with high temperature and low rainfall. About 79.8% of irrigation reservoirs in Daegu, Gyeongbuk, and Ulsan with high climate exposure and sensitivity resulted in a 'High' level of potential impact. On the contrary, 64.5% of the study reservoirs in Gyeongnam and Gangwon showed 'Low' in potential impact. In further studies, it is required to reorganize the proxy variables and the weights in accordance with practical alternatives for improving adaptive capacity to drought, and it is expected to contribute to establishing a framework for vulnerability assessment of an irrigation reservoir.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.767-781
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• 2013

In this paper, we proposes the AC input voltage and current sensorless control scheme to control the input power factor and DC output voltage of the three-phase Z-source PWM rectifier. For DC-link voltage control which is sensitive to the system parameters of the PWM rectifier, fuzzy-PI controller is used. Because the AC input voltage and current are estimated using only the DC-link voltage and current, AC input voltage and current sensors are not required. In addition, the unity input power factor and DC output voltage can be controlled. The phase-angle of the detected AC input voltage and estimated voltage, the response characteristics of the DC output voltage according to the DC voltage references, the FFT results of the estimated voltage and current, efficiency, and the response characteristics of the conventional PI controller and fuzzy-PI controller are verified by PSIM simulation.

• Journal of dental hygiene science
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• v.18 no.5
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• pp.305-311
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• 2018

The purpose of this study was to identify the effect of providing toothbrushing by professionals as part of oral hygiene education for the elderly. We randomly visited 12 centers in the metropolitan city and analyzed the data of 114 participants among 310 early registrants aged >65 years, who participated in the study at all 3 time points. The subjects were categorized into an experimental group (odd-numbered visits) and a control group (even-numbered visits). Oral hygiene practices were provided for both experimental and control groups, but professional toothbrushing was performed in a different manner in the experimental group. Differences in plaque index (PI) according to the subjects' general characteristics and oral health status were assessed using the t-test, and the effect of PI difference between the experimental and control groups was assessed by repeated measure two-way analysis of variance. A stepwise multiple regression analysis was used to analyze factors affecting the PI. At baseline, the mean overall PI was 61.82. In both experimental and control groups, the PI significantly reduced from the baseline (p<0.01). At 5 weeks, the experimental group showed a decrease of 27.16 points from the baseline, and the 10-week PI was similar to the 5-week PI. The control group showed a decrease of 14.87 points from the baseline, and the PI increased by 5.74 points at 10 weeks. PI-related factors were gender and self-xerostomia. The PI was lower in the female group and the group with self- xerostomia (p<0.01). It is important to select an appropriate method to educate elderly subjects on proper removal of dental plaque and to habituate correct behavior, which requires inclusion of a direct toothbrushing intervention by a specialist.

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.33-38
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• 2012

Growth response of 'Sambokkul' watermelon grafted onto different rootstocks including 4 $Citrullus$ rootstocks and 3 other cucurbitaceous rootstocks was evaluated at two different temperature regimes. Significant reduction in plant growth rate was observed in plants grown at low temperatures (LT) as compared to those grown at normal or optimal temperatures. Relative growth reduction were 40~47% for vine length, 39~51% for total leaf area, 38~59% for shoot fresh weight, and 57~87% for plant dry weight, respectively. Watermelon rootstock PI 482322 showed comparable plant growth as the most popular rootstock 'Shintozwa' even at LT. 'Sambokkul' watermelon grafted onto watermelon hybrids, 'PI 271969 ${\times}$ PI 296341' and 'PI 271769 ${\times}$ Calhoun Gray', showed comparable plant growth as 'FR Dantos' bottle gourd rootstock. Index of growth ability at LT, which was calculated on the basis of reduced rate of vine length, dry weight and leaf area, was significantly high in $C.$ $martinezii$, 'Shintozwa', PI 482322, and 'PI 271769 ${\times}$ PI 296341' rootstocks (50% or higher) and low in own-rooted 'Sambokkul' or in watermelon plants on 'Knight' rootstock. Watermelon hybrids, 'PI 271969 ${\times}$ PI 296341' and 'PI 271769 ${\times}$ Calhoun Gray', showed better or at least comparable growth at low temperatures as compared to 'FR Dantos', confirming the feasibility of using watermelon rootstocks even in low temperature conditions.

• The Journal of the Korean dental association
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• v.48 no.5
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• pp.371-378
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• 2010

The objective of this study was to compare the effectiveness of essential oil mouthrinse and interdental brush for oral hygiene in orthodontic patient. 90 patients, with fixed orthodontic appliances, were divided into 3 groups(Group 1: patients who had only used toothbrush, group 2: toothbrush + essential oil mouthrinse, group 3: toothbrush + interdental brush). Then, plaque index(PI) and gingival index(GI) were evaluated at before(T0), 3 weeks after(Tl) and 6 weeks after(T2) the experiment. The present study revealed the following conclusions: (1) There was statistically significant decrease in PI and GI of groups 2 and 3 comparing to those of group 1 during 6 weeks.(p<0.05) (2) There was no significant difference in the level of decrease in PI and GI between group 2 and group 3.(p<0.05) The present study thus implied that use of mechanical or chemical aid such as interdental brush and mouth rinse in addition to toothbrushing may help maintaining oral hygiene in patients undergoing fixed orthodontic treatment for prolonged duration.

• Journal of Environmental Health Sciences
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• v.38 no.5
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• pp.380-385
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• 2012

Background: Manganese (Mn) has been found to increase the signal intensity of the globus pallidus (GP) on T1-weighted magnetic resonance images (MRI). We performed this study in order to determine the features of liver disease that correlate with pallidal signal intensities. Methods: We assessed blood Mn levels and pallidal signals in T1-weighted MRI in 49 patients with liver cirrhosis and 23 healthy controls. Results: Increased signal intensity in the GP was observed in 30 of 49 (61.2%) patients with liver cirrhosis, with the pallidal index (PI) in patients with Child-Pugh classes B and C differing significantly from the PI in controls. Multiple linear regression analysis showed that blood Mn concentrations and Child-Pugh scores in cirrhotics were significantly associated with increased PI after controlling for other confounders (p<0.05 each). Conclusions: Pallidal signals on T1-weighted MRI are mainly observed in advanced liver cirrhosis. The present study suggests that advanced liver cirrhosis may be a human model for manganism.

• The Korean Journal of Pain
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• v.9 no.1
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• pp.130-134
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• 1996

Background: This study was designed to determine the distance from skin to lumbar epidural space in obstetric parturients and whether weight, height, or PI (ponderal index, $kg/m^2$) might influence the epidural depth. Methods: 71 obstetric patients undergoing elective cesarean section during epidural anesthesia in L2-3 level were partitioned into groups according to their prepregnant BMI(body mass index), and in each group weight, height, PI, epidural depth were measured. Results: All patients were classified as underweight(n=18), normal(n=49), overweight(n=4) and no one was partitioned into obese group. the distance from skin to lumbar epidural space was found to be 3.7 cm(underweight), 4.1 cm(normal), 4.7 cm(over weight) and total mean distance was found to be 4.0 cm. The epidural depth had correlation with weight and height in underweight, and weight and PI in normal, but had no correlation with any measurements in overweight group. Conclusion: These results suggest body weight may be a useful parameter for predicting the distance from skin to lumbar epidural space in underweight and normal weight obstetric parturients.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.1
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• pp.18-25
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• 2000

In the two-mass servo system driving a load through a flexible shaft, a shaft torsional vibration is often generated. PI controller has been generally used is speed control of such system because of the simplicity of structure and related theory. This paper presents the inertia ratio of the PI servo control system which can be designed by using optimal pole assignment method is fixed. Therefore, it's difficult to obtain the desired control characteristics for different systems only by PI control algorithm. To solve this problems the two-mass speed control system with PID controller is designed by using pole assignment method and an optimum PID parameters are derived by evaluating ITAE(Integral of time multiplied by the absolute error) performance index. But this design method has some problems due to a trade-off between the fast command following property and the attenuation of disturbances and vibrations. In this paper, 2-DOF PID control method which satisfies the command following property, the reduction of overshoot and the property of disturbance rejection at the same time is proposed. This is a practical speed controller using the desired value filter and the feedforward gain. From several simulations, it's clarified that the proposed 2-DOF PID controller is useful for the two-mass system, in comparison with the conventional PID controller.