• Journal of the Korean Society for Precision Engineering
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• v.16 no.9
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• pp.41-47
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• 1999

The scale of dendritic structure of a cast preform plays a key role in determining the mechanical properties of cast/forged products. In this study, casting experiments are carried out to reduce dendrite arm spacing (DAS) to smaller than 20 ${\mu}$m by increasing cooling rate of the mold and then to spheriodize dendritic structures by addition of alloying elements such as Zr and Ti-B. From the casting experiments, appropriate casting conditions for producing the cast preform of a motorcycle connecting rod are obtained. To obtain fine microstructures of the cast preform, mold temperature must set to be low whilst cooling rate being high. When cooling rate is 10 $^{\circ}C$/s, the size of DAS is 17.4 ${\mu}$m. And the degree of spheriodization of a grain in the cast preform is described by aspect ratio, which is defined as the ratio of major and minor radii of an elliptical grain. When 0.5% Zr and 0.24 % Ti+B are added to the molten aluminum alloy, the best aspect-ratio 0.75 is obtained. After forging the cast preform of a motorcycle connecting rod, the microstructure and mechanical properties of the cast preform are compared with those of the cast/forged product. Cast/forged products are superior in microstructure and in mechanical properties such as ultimate strength, elongation, and hardness.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.2
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• pp.190-198
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• 1995

Many industrial servo amplifiers employ power transister as output device. Thyristor converters are not adopted to drive servo motor, although thyristor is superior to power TR in power rating, noise immunity, price, and size. The reason is, thyristor has no ability of self turn - off. Here in this paper line commutation, in which thyristor is turned off naturally since cathode voltage is higher than anode as time goes by, is employed to turn on thyristor with a delicate sequence. We developed thyristor servo amplifier which does not cause any damage on thyristor because it is designed to prevent triggering the two SCRs in the same arm simultaneously. And it was made clearly how to trigger SCR without any power line shorting and also harmonic analysis is carried out with the aid of FFT analyzer and proved that it can be used even severe reactive load. The designed circuit operated as a good DC amplifier in conventinal servomotor and the results can be use as a position control system application.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup2
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• pp.273-280
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• 2001

Objectives : The purpose of this study is to assess the long-term outcome and delayed complications of Gamma Knife radiosurgery for low grade glioma(LGG). Methods : Among 31 patients of LGG who had been treated by using Leksell Gamma Knife between March 1992 and December 1996, we could follow up more than 5 years(range 5-9 years) in 17 patients and evaluated their clinical feature, changes of tumor volume and post-radiosurgical complications. Results : During the mean follow-up period of 7.6 years, the tumor was decreased in 5 patients(29.4%), unchanged in 4(23.5%), increased in 4(23.5%) and recurred in 4(23.5%). The tumor control rate was 52.9%(9/17). We have experienced eighteen postradiosurgical complications in 10 patients(58.8%). Early complication was none and delayed complications included radiation necrosis with cyst in ten cases, bleeding in five, radiation-induced edema in one and malignant transformation in one. Two patients ultimately died as a result of tumor progression during the follow-up period. The mortality rate was 11.7%. Conclusion : Gamma Knife radiosurgery may be useful as an adjunctive therapy for small volume, deep-seated LGG. Although radiosurgery can effectively prevent growth of solid tumor, several delayed complications such as radiation necrosis, cyst formation, bleeding or malignant transformation can develop during the long-term followup period. Because of the possible slow growth rate of LGG and development of the delayed complications, the long-term efficacy of radiosurgery requires further analysis.

• Journal of Nutrition and Health
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• v.5 no.2
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• pp.83-89
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• 1972

A survey on the nutritional state was conducted from June 11 to Nov. 30, 1971, on 673 women workers $(16{\sim}25\;yrs)$ Jorking in a factory of food industry. Total body fat content was measured by skin-fold thickness (S. F. T.) with caliper at three region of the body. And it was calculated by regression equation, with the following conclusions were abtained. 1. The mean with standard deviation body height and weight of the Korean women workers were $155.0{\pm}4.21\;cm$ and $50.1{\pm}5.31\;kg$; respectively. 2. Their mean skin-fold thickness with their standard deviation triceps region of upper arm, 14.3{\pm}3.42$; Subscapular region, $18.0{\pm}5.57mm$; Abdominal region, $19.3{\pm}4.87mm$ and total aveager, 17.2{\pm}3.91mm$. 3. The body fat contents according to body fat weight regression equation were;fat weight. 10.7 kg; fat-free weight, 39.4kg; fat weight/ fat-free weight, 27.5%; fat-free mass/ total body mass 77.6%, and fat weight/ total body mass,21.6%. 4. Since the sknin-fold thickness between the triceps and upper abdominal region and between the former and Subscapular region were correlated with the coefficients of 0.838 and 0.615 respectively. and the following regression equations were established. a) S. F. T. of Subscapular region $(mm)=0.929{\times}$S. F. T. of triceps region (mm)+4.707. b) S. F. T. of Abdominal $region(mm)=1.24{\times}$S. F. T. of triceps region(mm)+1.50. Nutritional survey on the women workers in a fact ory of food industry, performed as above by the S. F. T. method, elucidated the fact that their nutritional state is as good as the control healthy female, and that their energy uptake may well be said to be satisfactory.

• The Journal of Korean Obstetrics and Gynecology
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• v.21 no.4
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• pp.193-206
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• 2008

Purpose: In spite of many arguments on the result of WHI (Women's Health Initiative) study, no one can deny the necessity for researches on the alternative treatment to HRT (hormone replacement therapy). In this study, the author wanted to investigate the method of precedent acupuncture RCTs (randomized controlled trials) to make out the appropriate acupuncture study design on postmenopausal and perimenopausal hot flashes in Korea. Methods: Precedent studies were investigated using Pubmed search and key-words "acupuncture and hot flash", "acupuncture and menopause", "acupuncture and vasomotor", limited to RCT, from 2000 to 2008 April. Results: As a result. 10 studies were searched. In the hereafter studies, multi-center clinical trials which consist of population group of postmenopausal and perimenopausal women that would be pre-stratified and more than 50 patients per treatment arm seem adequate. Sham control study can make out the proper consequence because many people are get used to acupuncture in Korea. Flexible choice of acupoints addressed an individual's symptoms using standardized algorithm is recommended. Treatment consist of 4 weeks' observation, 11 acupuncture sessions during 7 weeks, follow-up of 3 months or more after treatment and hot flash score as a primary outcome measure seem appropriate. After all, higher level of description according to global standard must be obtained in the study report and publishing. Conclusion: The researchers should develope the methodology of acupuncture clinical trial on the postmenopausal and perimenopausal hot flashes.

• The Journal of Korean Obstetrics and Gynecology
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• v.27 no.1
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• pp.140-151
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• 2014

Objectives: Cold hypersensitivity has been regarded to be associated with digestive function. This study is aims to evaluate the correlation between digestive function and coldness of hands. Methods: We made a research of 80 women who is in ${\bigcirc}{\bigcirc}$ University. The patients were subjected to thermometer, and those with thermal difference between upper arm and palm were diagnosed with cold hypersensitivity. The patients were divided into two group by cold hypersensitivity group (n=20), and non-cold hypersensitivity group (n=19), and 39 women are mesured by Nepean dyspepsia index-Korean version (NDI-K) to evaluate the severity of functional dyspepsia. Results: There was no difference between two groups on age, height, weight. In functional dyspepsia symptom score, 6 symptoms (Pain in upper abdomen, Burning in upper abdomen, Cramps in upper abdomen, Pressure in upper abdomen, Vomiting, Bad breath) out of 15 were significantly increased in cold hypersensitivity group compared with non-cold hypersensitivity group. And in quality of life score, 3 domains (Tension/sleep, Interference with daily activities, Knowledge/control) out of 5, and total quality of life score were significantly decreased in cold hypersensitivity group compared with non-cold hypersensitivity group. Conclusions: This study shows the correlation between cold hypersensitivity and digestive function.

• Nutrition Research and Practice
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• v.13 no.2
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• pp.105-114
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• 2019

BACKGROUND/OBJECTIVES: Several previous studies have investigated whether regular walnut consumption positively changes heart-health-related parameters. The aim of this study was to investigate the effects of daily walnut intake on metabolic syndrome (MetS) status and other metabolic parameters among subjects with MetS. SUBJECTS/METHODS: This study was a two-arm, randomized, controlled crossover study with 16 weeks of each intervention (45 g of walnuts or iso-caloric white bread) with a 6 week washout period between interventions. Korean adults with MetS (n = 119) were randomly assigned to one of two sequences; 84 subjects completed the trial. At each clinic visit (at 0, 16, 22, and 38 weeks), MetS components, metabolic parameters including lipid profile, hemoglobin A1c (HbA1c), adiponectin, leptin, and apolipoprotein B, as well as anthropometric and bioimpedance data were obtained. RESULTS: Daily walnut consumption for 16 weeks improved MetS status, resulting in 28.6%-52.8% reversion rates for individual MetS components and 51.2% of participants with MetS at baseline reverted to a normal status after the walnut intervention. Significant improvements after walnut intake, compared to control intervention, in high-density lipoprotein cholesterol (HDL-C) (P = 0.028), fasting glucose (P = 0.013), HbA1c (P = 0.021), and adiponectin (P = 0.019) were observed after adjustment for gender, age, body mass index, and sequence using a linear mixed model. CONCLUSION: A dietary supplement of 45 g of walnuts for 16 weeks favorably changed MetS status by increasing the concentration of HDL-C and decreasing fasting glucose level. Furthermore, consuming walnuts on a daily basis changed HbA1c and circulating adiponectin levels among the subjects with MetS. This trial is registered at ClinicalTrials.gov as NCT03267901.

• PNF and Movement
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• v.16 no.3
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• pp.451-460
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• 2018

Purpose: The purpose of this study was to investigate the effects of a modified constraint induced movement therapy (mCIMT) using proprioceptive neuromuscular facilitation (PNF) on the upper extremity function and activities of daily living (ADLs) in patients with subacute stroke. Methods: Fourteen participants with subacute stroke were randomly assigned to a group using both mCIMT and PNF or a group using mCIMT alone. Each group underwent twenty sessions (1 h/d, 5 d/wk) for 4 weeks. Patients were assessed with the action research arm test (ARAT), the Fugl-Meyer assessment for the upper extremities (FMA-UE), the Modified Barthel Index (MBI), and motor activity logs (MALs; amount of use [AOU] and quality of movement [QOM]). Results: Both the experimental group and the control group showed significant intragroup improvement in the ARAT, FMA-UE, MBI, and MAL-AOU (p<0.05). The group using both mCIMT and PNF exhibited greater improvement in the ARAT, FMA-UE, MBI, and MAL-AOU than did the group using mCIMT alone. Statistical analyses showed significant differences in the ARAT (p=0.01), FMA-UE (p=0.01), MBI (p=0.00), and MAL-AOU (p=0.01) between the groups. Conclusion: This study applied mCIMT combined with PNF for subacute stroke patients, and the results showed significant improvements in the patients' upper extremity function and ADLs. Therefore, mCIMT using PNF may be more effective than mCIMT alone in improving upper limb function and ADLs in patients with subacute stroke.

• Physical Therapy Rehabilitation Science
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• v.8 no.1
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• pp.52-59
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• 2019

Objective: The purpose of this review was to investigate whether motor imagery training has an effect on the recovery of upper extremity function in individuals with hemiparetic stroke or not. Design: A systematic review and meta-analysis. Methods: PubMed and three other databases were searched up to December 18th, 2018 and randomized controlled trials (RCTs) evaluating motor imagery training on upper extremity function in persons with a diagnosis of hemiparetic stroke were included. This review selected the following information from each study: surname of the first author, published year, nation, population, intervention, therapeutic intensity of intervention, therapeutic comparison, outcome measures, additional therapy, summary of results, and descriptive statistics of outcome measures. Results: This review selected seventeen RCTs with 487 stroke survivors and the following intervention methods: six motor imagery training with additional therapeutic technology, two motor imagery training with additional modified constraint-induced therapy, four mirror therapy, and five motor imagery training. Ten RCTs were eligible for meta-analysis after systematic review. The motor imagery group were more effective than the control group based on the Fugl-Meyer assessment (3.43; 95% confidence interval [CI], 1.65 to 5.22; heterogeneity [$chi^2=8.03$, df=8, $I^2=0%$], test of overall effect Z=3.76; test for subgroup differences [$chi^2=2.56$, df=2, $I^2=21.8%$]) and the Action Research Arm Test (1.32; 95% CI, -8.12 to 10.76; heterogeneity [$Tau^2=70.74$, $chi^2=15.22$, df=3, $I^2=80%$], test of overall effect Z=3.76). Conclusions: The results of this review suggests that motor imagery shows positive effectiveness on improving upper extremity function in persons with hemiparetic stroke.

• Journal of Gastric Cancer
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• v.20 no.4
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• pp.395-407
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• 2020

Purpose: A phase II study was conducted to evaluate the safety and efficacy of preoperative, intra-arterial perfusion of epirubicin, etoposide, and oxaliplatin combined with oral chemotherapy S-1 (SEEOX) for the treatment of type 4 gastric cancer. Materials and Methods: A single-center, single-arm phase II trial was conducted on 36 patients with histologically proven type 4 gastric cancer without distant peritoneal or organ metastasis. Patients received 3, 21-day courses of SEEOX preoperative chemotherapy. The primary endpoint was overall survival (OS) and the secondary outcomes assessed were chemotherapeutic response, radical resection rate, pathological regression, toxicities, postoperative morbidity, and mortality. Results: All patients were at an advanced stage of cancer (stage III or IV) and completed the entire course of treatment. Based on changes in tumor volume and peritoneal metastasis, the objective response rate was 55.6% (20/36; 95% confidence interval [CI], 38.5%-72.6%) and the disease control rate was 69.4% (25/36; 95% CI, 53.6%-85.3%). The radical resection rate was 75% (27/36; 95% CI, 60.1%-89.9%) and the proportion of R0 resections was 66.7% (21/36; 95% CI, 50.5%-82.8%). The pathological response rate was 33.3%, of which 13.9% showed complete pathological regression. The median survival was 27.1 months (95% CI, 22.24-31.97 months), and the 2-year OS was 48.5% (95% CI, 30.86%-66.1%). Conclusions: Preoperative SEEOX is a safe and effective treatment for type 4 gastric cancer. Based on these preliminary data, a phase III study will be conducted to confirm the superiority of this regimen over standard treatment.