• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.146-149
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• 2003

To control the position, velocity and torque of the ultrasonic motor, a great variety of method are proposed such as the amplitude, phase difference, frequency and so on. In the case of phase difference method, it has some advantages: it can control the direction and velocity of rotation only adjusting the phase difference and it has wide control-band. During the USM driving on adjusting phase difference, its characteristic was transformed by the change of resonance-frequency of stator, which means that the resonance frequency is different according to the phase difference. Consequently, we need to set up the most suitable driving frequency according to each phase difference.

• Journal of the Korean Society of Industry Convergence
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• v.14 no.3
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• pp.113-119
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• 2011

This study analyzed facts affecting the performance of refrigeration systems after throttling actions, by changing the amount of refrigerant according to adjusting the opening of manual expansion valve to 80%, or 20% with vapor compressional refrigeration training equipment. At opening of 20%, the inlet and outlet temperature of compressor, subcooling and superheat, condenser heat, refrigeration effect, flash gas heat, coefficient of performance were higher, while at 80%, condensing pressure, evaporating pressure, compression work were higher, Thus, we could see changes in the amount of refrigerant affect the performance of the refrigeration system.

• Journal of Korean Neurosurgical Society
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• v.65 no.3
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• pp.439-448
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• 2022

Objective : Craniopharyngiomas (CPs) are associated with hypothalamic damage that causes hypothalamic obesity, however, the mechanisms underlying CP-related postoperative weight gain remain debatable. This study aimed to elucidate whether the major determinant of postoperative weight gain in patients with CP is hypothalamic injury or steroid replacement therapy. Methods : We included 48 adult patients with CP (age ≥18 years) who underwent transsphenoidal surgery between 2010 and 2018 in a single tertiary center, and whose body weight was measured pre- and postoperatively (<120 days after the surgery). We recruited 144 age- and body mass index-matched patients with non-functioning pituitary adenoma (NFPA) as controls. Results : Patients with CP experienced greater postoperative weight gain than patients with NFPA (3.0±5.1 vs. 0.1±3.6 kg, p<0.001). The prevalence of postoperative steroid use was significantly higher in patients with CP than in those with NFPA (89.6% vs. 34.0%, p<0.001). Steroid replacement therapy and CP were associated with postoperative weight gain after adjusting for covariates in overall patients (p=0.032 and 0.007, respectively). In subgroup analysis with postoperative steroid users, weight gain was significantly greater in patients with CP (n=43, 0.96±0.25 kg/month) than in patients with NFPA (n=49, 0.26±0.23 kg/month) even after adjusting for the daily steroid dose (p=0.048). Conclusion : Patients with CP experience greater postoperative weight gain than those with NFPA. Hypothalamic damage itself as well as steroid replacement may contribute to the postoperative weight gain in patients with CP.

• Korean Journal of Clinical Pharmacy
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• v.30 no.4
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• pp.264-269
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• 2020

Background: Inflammatory diseases can increase the prevalence of anemia. Recent studies confirmed that the prevalence of anemia is increased by atopic dermatitis (AD), a chronic inflammatory disease. Therefore, we aimed to elucidate the correlation between AD severity and prevalence of anemia. Methods: We used data of pediatric patients from the Health Insurance Review and Assessment Service (HIRA-PPS-2016). We included pediatric patients (<18 years) with AD diagnosis who were prescribed medications for AD. We applied a propensity score method with inverse probability of treatment weighting (IPTW) adjusting for differences in prevalence of confounders and performed IPTW logistic regression to evaluate associations between the anemia and severity of AD. Results: In total, 91,501 patients (mild AD: 47,054 patients; moderate-to-severe AD: 44,447 patients) <18 years who were prescribed drugs for AD were analyzed. Analysis of the probability of patients with mild AD and prevalence of anemia as a reference revealed an odds ratio (OR) of 1.159 (95% CI, 1.109-1.212; p<0.001) in moderate-to-severe AD patients, indicating a correlation between anemia prevalence and AD severity. Subgroup analysis according to gender, age group, and type of health insurance revealed there was an association between AD severity and anemia except in patients equal or older than 7 years. Conclusion: The prevalence of anemia increased with AD severity despite adjusting for confounding factors. Our results support the hypothesis that AD can cause anemia, and anemia prevalence could be increased in severe AD patients. Further studies are needed to establish a pathological basis.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.2
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• pp.187-202
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• 2009

Objectives : The purpose of this study is to investigate the efficacy of adjusting leg length inequality(LLI) by chuna manual treatment for post-stroke hemiplegia. Methods : 39 patients with stroke-originated hemiplegia who had leg length inequality were included in this study. Chuna manual treatment at pelvic girdle was applied to 20 patients and they had been treated by general oriental rehabilitation therapy(test group). The other 19 patients had been treated by general oriental rehabilitation therapy only(control group). Outcomes were assessed by Modified Barthel Index(MBI), Berg Balance Scale(BBS), lower extremity Fugl-Meyer Assessment(FMA) at the point of beginning and end of the study. Results : 1. In terms of activity of daily living(ADL), test group showed statistically meaningful differences compared to control group(p<0.05). In subacute group(onset had been past under 6 months), test group didn't showed statistically meaningful differences compared to control group. In chronic group(onset had been past over 6 months), test group didn't showed statistically meaningful differences compared to control group. 2. In terms of lower extremity function and balance, test group showed statistically meaningful differences compared to control group(p<0.05). In subacute group, test group didn't showed statistically meaningful differences compared to control group. In chronic group, test group showed statistically meaningful differences compared to control group(p<0.01). 3. In terms of lower extremity function of hemiplegic side, test group showed statistically meaningful differences compared to control group(p<0.05). In subacute group, test group didn't showed statistically meaningful differences compared to control group. In chronic group, test group showed statistically meaningful differences compared to control group(p<0.05). Coclusions : Adjusting LLI by chuna manual treatment is efficacious for rehabilitation of stroke-originated hemiplegia, in terms of ADL, balance and lower extremity function, and is especially efficacious for chronic patients.

• Journal of Preventive Medicine and Public Health
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• v.34 no.1
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• pp.9-20
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• 2001

Objectives : To explore the relationship between Percutaneous Transluminal Coronary Angioplasty(PTCA) volume and the associated immediate outcome. Methods : A total of 1,379 PTCAs were peformed in 25 hospitals in Korea between October 8 and December 31 in 1997. Data from 1,317 PTCAs (95.5%) were collected through medical record abstraction. Inter-observer reliability of the data was examined using the Kappa statistic on a subsample of 110 PTCA procedures from five hospitals. Intra-observer reliability of the data was also examined. PTCA success and immediate adverse outcomes were selected as the outcome variables. A successful PTCA was defined as a case that shows less than 50% diameter stenosis and more than 20% reduction of diameter stenosis. Immediate adverse outcomes included deaths during the same hospitalization, emergency coronary artery bypass graft (CABG) within 24 hours after PTCA, and acute myocardial infarction within 24 hours after PTCA. The numbers of PTCAs performed in 1997 per hospital were used as the volume variables. Results : Without adjusting for patient risk factors that may affect outcomes, procedures at high volume hospitals ($\geq200$ cases per year) had a greater success rate (P=0.001) than low volume hospitals. There was a marginally significant difference (P=0.070) in major adverse outcome rates between high and low volume hospitals. After adjusting for risk factors, there were significant differences in procedural failure and major adverse outcome rates between high and low volume hospitals. Conclusions : After adjusting for patient clinical risk factors, the hospital volume of PTCA was associated with immediate outcomes. It is recommended that a PTCA volume per year be established in order to improve the immediate outcome of this procedure in Korea.

• Journal of Acupuncture Research
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• v.22 no.2
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• pp.1-12
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• 2005

Objective: With the onset of stroke, white blood cells release several proinflammatory cytokines, including interleukin (IL)-6, IL-10, and tumor necrosis factor $(TNF)-{\alpha}$. It has been proven in previous studies that the release of these cytokines is related to the extent of damage to the brain and to overall prognosis. However, no studies have yet been performed to determine the connection with IL-6 and IL-10. Thus, this study is performed to see whether polymorphisms of IL-6, IL-10, and $TNF-{\alpha}$ genes that show increased serum concentration with the onset of stroke are related to stroke attack in Koreans. Methods : Peripheral blood samples derived from patients with stroke (n=100) and healthy controls (n=100) were taken under informed consent. In subjects with stroke, blood samples were obtained within 24 hours of stroke onset. Genomic DNA was isolated using the Wizard DNA Purification Kit (Promega, Madison, WI). Results : 1. Subjects with Heterozygote (GA) and Homozygote (AA) $TNF-{\alpha}$ gene types showed 2.433 and 20.457 times higher risks of being attacked by stroke, respectively, compared to subjects with wild type (GG) $TNF-{\alpha}$ gene type. The data was still statistically significant after adjusting for age, sex, history of smoking, and history of alcohol drinking. 2. Subjects with Homozygote (CC) IL-6 gene type showed 182.033 times higher risk of being attacked by stroke, compared to subjects with wild type (GG) IL-6 genes. This data was statistically insignificant (p=0.700). The data was still statistically insignificant after adjusting for age, sex, history of smoking, and history of alcohol drinking. 3. Subjects with Heterozygote (GA) and Homozygote (GG) IL-10 gene types showed 8.785 and 3.303 times higher risks of being attacked by stroke, respectively, compared to subjects with wild type (AA) IL-10 genes. The data was still statistically insignificant after adjusting for age, sex, history of smoking, and history of alcohol drinking. Conclusion : Our results suggest that the investigated $TNF-{\alpha}$ and IL-10 gene polymorphisms play an important role in stroke attack, but IL-6 gene polymorphism has not been found to associated with stroke.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1800-1803
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• 2002

The pulsed power system was widely making use good of many industrial and environments. The pulse generator generally required for short pulse duration and high peak value was forced to consider its volume and economy. In this paper, this system is designed and fabricated which has a compact size of pulse generator with switched MOSFET. We have studied the removal of rust material using Arc discharging in pulsed power system. It have tested their characteristics by adjusting variable voltage charging and pulse repetition rate. As a result, We can eliminate rust materials with this device.

• Journal of the Korean Dietetic Association
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• v.19 no.3
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• pp.223-235
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• 2013

The purpose of this study was to identify the association between health-related behaviors including smoking, alcohol intake, and the practice of a low-salt diet using data from a Community Health Survey conducted in 2008. The study subjects were 129,151 persons (19 years and older) without cardiovascular diseases or diabetes mellitus diagnosis history. An index for evaluating low salinity was created by summing three low salinity-related questions (range: 0~3), and a low-salt diet was defined if the index of low salinity was 3. We examined the levels of smoking and alcohol intake according to the index of low salinity, and conducted multiple logistic regression analysis to examine the odds ratios of low-salt diet practice in relation to smoking and drinking behavior, adjusting for general characteristics. The smoking and drinking status significantly improved as the level of low salinity index increase. Adjusting for general characteristics, those with smoking, alcohol intake, or a combined habit of the two behaviors had significantly lower odds ratios for practice of a low-salt diet. In conclusion, smoking and drinking behavior were negatively associated with the practice of a low-salt diet. Based on these findings, it may be necessary to have comprehensive nutritional education programs that consider the multiple effects of smoking, drinking, and a low-salt diet.

• Journal of Korean society of Dental Hygiene
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• v.11 no.5
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• pp.783-790
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• 2011

Objectives : The purpose of this study was to examine students' difficulties in the process of oral radiography practice, to raise awareness of the importance and necessity of oral radiography and decipher, and to provide some information on effective ways of oral radiography practice. Methods : The subjects in this study were 285 dental hygiene students at K college, who included 153 sophomores and 132 graduates-to-be from June to November, 2010. Results : 1. The parts of the anatomy structure that they found it most difficult to decipher were maxillary molar(25.3%) and lower molar(22.1%). 2. They made during oral radiography was an improper film positioning(35.1%). 3. The part of bisecting technique was adjusting vertical and horizontal angles(53.0%). 4. The part of paralleling technique was positioning XCP in the oral cavity(44.2%). 5. The part of bite-wing technique was adjusting vertical and horizontal angles(38.2%). 6. The part of occlusion technique was positioning film and tube head(36.5%). 7. The part of panorama technique was finding out program setting(42.5%). Conclusions : The findings of the study indicated that in terms of anatomy structure decipher, it's especially difficult to decipher maxillary molar and lower molar, and that film positioning was difficult to do in the process of oral radiography. What difficulties they faced in applying each kind of oral radiography techniques and which part of the oral cavity they found it hard to radiograph were analyzed as well in this study. Given the findings of the study, more intensive practice is required to help students to acquire accurate oral radiography techniques to ensure their successful job performance in the future.