• Journal of Power Electronics
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• v.17 no.1
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• pp.172-180
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• 2017

The repetitive control (RC) strategy is widely used in AC power systems because of its high performance in tracking period signal and suppressing steady-state error. However, the dynamic response of RC is determined by the fundamental period delay $T_0$ existing in the internal model. In the current study, a ($nk{\pm}i$)-order harmonic RC structure is proposed to improve dynamic performance. The proposed structure has less data memory and can improve the tracking speed by n/2 times. $T_0$ proves the effectiveness of the ($nk{\pm}i$)-order RC strategy. The simulation and experiments of ($6k{\pm}1$)-order and ($4k{\pm}1$)-order RC strategy used in the voltage source inverter is conducted in this study to control the harmonic current source, which shows the validity and advantages of the proposed structure.

• Korean Journal of Adult Nursing
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• v.15 no.1
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• pp.67-77
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• 2003

Purpose: This study was to examine the effects of music therapy on the levels of anxiety and discomfort in patients undergoing gastrofibroscopy. Method: This study was equivalent control group pre-post test design. The subjects were 61 patients who visited H hospital internal medicine department for gastrofibroscopy ; 31 were randomly selected for the control group and the remaining 30, for the experimental group. Result: 1. The experimental group who used music therapy showed a significantly lower level of anxiety during gastrofibroscopy than the control group. 2. The experimental group revealed a lesser change in pulse rate between pre and post gastrofibroscopy than the control group. 3. There was a significant difference in the levels of subjective and objective discomfort during gastrofibroscopy between the two groups. Conclusion: The results suggested that music therapy may help relieve anxiety and discomfort for patients undergoing gastrofibroscopy. These results showed that the use of music aided in the reduction of anxiety and discomfort during the unpleasant diagnostic procedure and, testing the effectiveness of music therapy deserves further study in other hospital settings.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.4
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• pp.201-207
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• 2005

This paper has investigated the sensorless vector control method of induction motor based on the stator flux oriented voltage equation and the digital low pass filter (LPF) with compensator of phase/gain. The Proposed vector control method is easy to decide the stator reference voltages and control of motor, since it is based on stator flux vector But this method has sensitive structure to excessive sensor noise and PWM pulsating components of stator currents because the measured stator currents are directly used to compensate the internal resistive voltage drop at the determination of stator reference voltages. To eliminate the noise sensitive of proposed vector drive, this paper propose the digital LPF with compensator of phase/gain base on orthogonal property of stator current vector in stationary $\alpha$, $\beta$ reference frame. The proposed methods have been simulated and implemented on a sensorless vector drive for 750W three-phase induction motor. The simulation and experimental results demonstrate effectiveness of the proposed methods.

• Tuberculosis and Respiratory Diseases
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• v.80 no.2
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• pp.169-178
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• 2017

Background: The purpose of this study was to assess the effect of our new video-assisted asthma education program on patients' knowledge regarding asthma and asthma control. Methods: Adult asthmatics who were diagnosed by primary care physicians and followed for at least 1 year were educated via smart devices and pamphlets. The education sessions were carried out three times at 2-week intervals. Each education period lasted at most 5 minutes. The effectiveness was then evaluated using questionnaires and an asthma control test (ACT). Results: The study enrolled 144 patients (mean age, $56.7{\pm}16.7years$). Half of the patients had not been taught how to use their inhalers. After participating in the education program, the participants' understanding of asthma improved significantly across all six items of a questionnaire assessing their general knowledge of asthma. The proportion of patients who made errors while manipulating their inhalers was reduced to less than 10%. The ACT score increased from $16.6{\pm}4.6$ to $20.0{\pm}3.9$ (p<0.001). The number of asthmatics whose ACT score was at least 20 increased from 45 (33.3%) to 93 (65.3%) (p<0.001). The magnitude of improvement in the ACT score did not differ between patients who received an education session at least three times within 1 year and those who had not. The majority of patients agreed to the need for an education program (95.8%) and showed a willingness to pay an additional cost for the education (81.9%). Conclusion: This study indicated that our newly developed education program would become an effective component of asthma management in primary care clinics.

• The Journal of Internal Korean Medicine
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• v.39 no.6
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• pp.1206-1224
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• 2018

Purpose: This systematic review was planned and performed in order to determine the clinical effectiveness of acupuncture for non-alcoholic fatty liver disease (NAFLD). Methods: We searched related randomized controlled trials in several medical online databases, including China National Knowledge Infrastructure (CNKI), Excerpta Medica dataBASE (EMBASE), Public/Publisher MEDLINE (PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), National Digital Science Library (NDSL), and Research Information Sharing Service (RISS). NAFLD related outcomes were extracted from the included trials and meta-analyzed. Results: From the 8 included trials, the values of the following examinations were extracted: liver ultrasonography, liver CT, body fat CT, aspartate transaminase (AST), alanine transaminase (ALT), gamma-glutamyltransferase (GGT), total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, fasting blood sugar (FBS), hosmeostatic model assessment for insulin resistance (HOMA-IR), weight, body mass index (BMI), waist hip ratio (WHR), obesity degree, body fat mass, body fat rate, leptin, malondialdehyde (MDA), and super oxide dismutase (SOD). In the 4 outcomes, cure rate in liver ultrasonography (RR=1.56; 95%CI=1.05~2.31; P=0.03), cure rate in liver CT (RR=2.23; 95%CI=1.33~3.72; P=0.002), TC (MD=-0.78; 95%CI=-1.41~-0.15; P=0.02), and TG (MD=-2.05; 95%CI=-3.88~-0.21; P=0.03), acupuncture was more effective than the control intervention. Conclusions: In this meta-analysis, acupuncture relieved hepatic steatosis, and reduced TC, and TG in NAFLD patients. more well-planned studies are still needed due to the heterogeneity and the considerable methodological flaws in the analyzed trials.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.8 no.2
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• pp.172-188
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• 2001

Purpose: The purpose of this research was to test the effectiveness of the nursing intervention, mutual goal setting, for patients who have had a mastectomy. Special reference was given to King's goal attainment theory and a theoretical framework for establishing an effective nursing strategy to enhance patient recovery is suggested. Method: This research employed a quasi-experimental design which consisted of pretest-posttest non-equivalent control and experimental groups. Data were collected from 37 patients who had a mastectomy and were hospitalized in the Department of Surgery of Y Medical Center from January 2001 to May 2001. The experimental group received the nursing intervention, mutual goal setting four times from the day before the operation to the fifth day after the operation while the control group received only routine nursing care. As postoperative recovery indicators, ROM of arm joints, arm circumference, pain, physical symptoms, oxygen saturation stress, anxiety and body image were measured. Result: The test results are as follows : 1) there were statistically significant differences between the experimental and control groups in extension and internal rotation of the shoulder Joint and flexion of the wrist joint. 2) there was no significant difference between the two groups in arm circumference. 3) there were no significant differences between the two groups in pain, physical symptoms, or oxygen saturation. 4) there were no significant differences between the two groups in stress, anxiety, or body Image. On the basis of research results, the following are recommended : 1) The effectiveness of nursing intervention in the acute recovery period as well as long term effects need to be investigated. 2) There is a need to develop an instrument to measure perception which facilitates goal attainment in the interactive setting between patients and nurses.

• The Journal of Korean Medicine
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• v.27 no.3 s.67
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• pp.14-25
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• 2006

Objectives: Samjunghwan has been known to be effective for the treatment of obesity. To show the effectiveness of Samjunghwan in a more scientific way, Samjunghwan extract was prepared and evaluated in high-fat diet rats by measuring the changes of body weight and lipid metabolism as described below. Methods: 245 g of crushed Samjunghwan was extracted with methyl alcohol. The extract was evaporated under reduced pressure to give 21.8 g. For 30 days, the control group rats were given a high fat diet, while the test group rats were given a high fat diet plus Samjunghwan extract. The normal group rats were given a normal diet. 50 mg of Samjunghwan extract per 1 kg of body weight was added to the diet for the test group rats. Results: The control group rats on a high fat diet gained weight by about 27-28% as compared to the normal group, whereas the test group rats on a high fat diet plus Samjunghwan extract lost weight about 6-8% as compared to the control group. A significant increase of liver weight caused by a high fat diet was also inhibited by the same Samjunghwan extract administration. Similar inhibitory effects on the food intake and on the epididymal adipose tissue weight were observed in the high fat diet rats by the administration of Samjunghwan extract. Serum and liver total lipid levels in the control group on a high fat diet increased significantly as compared to the normal group, whereas their serum and liver levels increased less on a high fat diet plus Samjunghwan extract administered test group than the control group. Impressively, serum leptin levels in the test group decreased almost to the level of the normal group, which was well in accordance with the decreased fat contents in the test group rats. Furthermore, the activities of hepatic acetyl-CoA carboxylase and fatty acid synthetase were increased in the control group, while their activities in the test group on a high fat diet plus Samjunghwan extract decreased nearly to the levels of normal group rats on a normal diet. Conclusions: These results showed that the obesity caused by a high fat diet was effectively inhibited the administration of Samjunghwan extract. Our results also showed that the abnormal lipid metabolism caused by a high fat diet was effectively cured by the administration of Samjunghwan extract.

• Journal of Trauma and Injury
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• v.33 no.1
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• pp.18-22
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• 2020

Purpose: Damage control laparotomy has contributed to improved survival rates for severe abdominal injuries. A large part of severe abdominal injury occurs with a concomitant pelvic bone fracture. The safety and effectiveness of internal fixation of pelvic bone fracture(s) has not been established. The aim of the present study was to evaluate infection risk in the pelvic surgical site in patients who underwent emergent abdominal surgery. Methods: This single-center retrospective observational study was based on data collected from a prospectively maintained registry between January 2015 and June 2019. Patients who underwent laparotomy and pelvic internal fixation were included. Individuals <18 and ≥80 years of age, those with no microbiological investigations, and those who underwent one-stage abdominal surgery were excluded. Comprehensive statistical comparative analysis was not performed due to the small number of enrolled patients. Results: A total of six patients met the inclusion criteria, and the most common injury mechanism was anterior-posterior compression (67%). The average duration of open abdomen was 98 hours (range, 44-98), and the time interval between abdominal closure and pelvic surgery was 98 hours. One patient (16.7%) died due to multi-organ dysfunction syndrome. Micro-organisms were identified in the abdominal surgical site in five patients (83%), with no micro-organisms in pelvic surgical sites. There was no unplanned implant removal. Conclusions: Internal fixation of pelvic bone fracture(s) could be performed in the state of open abdomen, and the advantages of early fixation may countervail the risks for cross contamination.

• Journal of Biomedical Engineering Research
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• v.28 no.5
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• pp.676-683
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• 2007

A non-invasive respiratory gated radiotherapy system like those based on external anatomic motion gives better comfortableness to patients than invasive system on treatment. However, higher correlation between the external and internal anatomic motion is required to increase the effectiveness of non-invasive respiratory gated radiotherapy. Both of invasive and non-invasive methods need to track the internal anatomy with the higher precision and rapid response. Especially, the non-invasive method has more difficulty to track the target position successively because of using only image processing. So we developed the system to track the motion for a non-invasive respiratory gated system to accurately find the dynamic position of internal structures such as the diaphragm and tumor. The respiratory organ motion tracking apparatus consists of an image capture board, a fluoroscopy system and a processing computer. After the image board grabs the motion of internal anatomy through the fluoroscopy system, the computer acquires the organ motion tracking data by image processing without any additional physical markers. The patients breathe freely without any forced breath control and coaching, when this experiment was performed. The developed pattern-recognition software could extract the target motion signal in real-time from the acquired fluoroscopic images. The range of mean deviations between the real and acquired target positions was measured for some sample structures in an anatomical model phantom. The mean and max deviation between the real and acquired positions were less than 1mm and 2mm respectively with the standardized movement using a moving stage and an anatomical model phantom. Under the real human body, the mean and maximum distance of the peak to trough was measured 23.5mm and 55.1mm respectively for 13 patients' diaphragm motion. The acquired respiration profile showed that human expiration period was longer than the inspiration period. The above results could be applied to respiratory-gated radiotherapy.

• The Journal of Internal Korean Medicine
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• v.40 no.1
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• pp.38-57
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• 2019

Objective: This study reviewed recent clinical research trends regarding the effects of herbal medicine treatment containing diuretic herbs on nonalcoholic fatty liver disease (NAFLD) in China. Methods: We reviewed clinical studies on NAFLD from the China Academic Journal of the China National Knowledge Infrastructure from January 1, 2016, to September 10, 2018. Results: Thirty-nine papers from 86 studies were reviewed. The most commonly used herbal prescriptions included Alismatis Rhizoma(澤瀉), Salviae miltiorrhizae Radix (丹蔘), Crataegii Fructus (山査), Polia Sclerotium (茯?), Bupleuri Radix (柴胡), and Cassiae Semen (決明子). The treatment effective rate, liver function test, serum lipid test, radiological examination, and symptom comparisons were used to analyze the treatments. In 32 of the papers, the effective treatment rate was 76.9%-100%, and the effectiveness in the experimental group was significantly higher than that in the control group (p<0.05). The risk ratio for the treatment effective rate was 1.26. The mean difference of ALT was -13.44 U/L (95% confidential interval, -24.45 U/L, -2.44 U/L, p=0.0166). Conclusion: Herbal medicine containing diuretic herbs has been demonstrated to be an effective and useful treatment for NAFLD. Clinical studies that are more scientific and systematic should be actively conducted in the future, and the results of the current study could be used as basic data in future clinical studies on herbal medicine treatment for NAFLD.