• The KSFM Journal of Fluid Machinery
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• v.6 no.3 s.20
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• pp.58-63
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• 2003

The performance of turbo pump drops rapidly and it gets into break-down when the void fraction reaches above the threshold value because the impeller flow passage is choked up with air bubbles. Phenomenological understanding of break-down and pumping recovery mechanisms under air-water two-phase flow conditions are therefore important for pump designers and essential assignment for researchers. In this paper, we investigated the characteristics of break-down and pumping recovery due to entrained air occurring inside a screw-type centrifugal pump which has a wide flow passage mainly through the findings of suction and discharge pressures, rotational speed, flow rate measurements and visualization.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.9
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• pp.47-54
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• 2003

In this study, to achieve the optimal conditions for mechanical hyper-fine pattern fabrication process, deformation behavior of the materials during indentation was studied with numerical method by ABAQUS S/W. Polymer (PMMA) and brittle materials (Si, Pyrex glass) were used as specimens, and forming conditions to reduce the elastic re cover and pile-up were proposed. The indenter was modeled a rigid surface. Minimum mesh sizes of specimens are 1 -l0nm. Comparison between the experimental data and numerical result demonstrated that the finite element approach is capable of reproducing the loading-unloading behavior of a nanoindentation test. The result of the investigation will be applied to the fabrication of the hyper-fine pattern.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.759-764
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• 2001

The separation performance of zigzag air classifier with angle of 90 degrees was studied using narrow size fractions of thin square samples and granular samples. The simulation results of air velocity inside the classifier indicated that the zigzag geometry induces a new pattern consisting of an upward flow and a circulation flow, Experimental results showed that overflow product recovery was described as an integral calculus of normal distribution as a function of dimensionless air velocity ( $V_{A}$ $V_{A50}$), where $V_{A}$ is superficial air velocity and $V_{A50}$ is the $V_{A}$ at the fifty percent recovery. The $V_{A}$ values were predicted using the equations derived from dynamics for a particle dropping in air. A monitoring system that utilizes changes in acoustic signals emitted during the process of air classification was developed to separate PET with desired recovery or grade. The technical feasibility of the on-line monitoring of the PET recovery and grade was demonstrated by measuring relative energy of the signals.signals.als.

• Korean Journal of Human Ecology
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• v.10 no.2
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• pp.205-213
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• 2001

A survey was conducted to investigate the intake pattern of health supplements and health foods by using questionnaire. The data were collected from 395 adults over middle age and analyzed with SAS program. The natural foods were most frequently taken among health supplements and health foods for health. There was no difference in pattern of health supplements or health foods intake between male and female. The item taken over 20% of subjects was health drinks, green tea, ginseng product, dietary fiber drink, honey, general tea, tonic medicine from natural foods, vitamin B, vitamin C from nutrition supplements, and Lactobacillus product from health supplements. As the main reason for taking health supplements or health foods, the male indicated recovery of fatigue and improvement of health, but the female indicated recovery of fatigue and protection or treatment on disease(p<0.001). The frequency of taking health supplements or health foods was once a day. About the effect of health foods 70.1%, of subjects answered not bad and 25% responded very helpful for their health. Twenty percent of subjects experienced side effects such as diarrhea. The results showed that the proper education program should be developed for consumer to choose suitable health supplements or health foods according to their dietary life and health condition.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.7
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• pp.541-551
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• 2009

Configuration of the inlet transition square duct (hereinafter referred to as "transition duct") for heat recovery steam generator (hereinafter referred to as "HRSG") in combined cycle power plant is limited by the construction type of HRSG and plant site condition. The main purpose of the present study is to analyze the effect of a variation in turbulent flow pattern by roof slop angle change of transition duct for horizontal HRSG, which is influencing heat flux in heat transfer structure to the finned tube bank. In this study, a computational fluid dynamics(CFD) is applied to predict turbulent flow pattern and comparisons are made to 1/12th scale cold model test data for verification. Re-normalization group theory (RNG) based k-$\epsilon$ turbulent model, which improves the accuracy for rapidly strained flow and swirling flow in comparison with standard k-$\epsilon$ model, is used for the results cited in this study. To reduce the amount of computer resources required for modeling the finned tube bank, a porous media model is used.

• Annals of Clinical Neurophysiology
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• v.16 no.1
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• pp.35-38
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• 2014

Japanese-B viral encephalitis (JE) usually has a monophasic illness pattern. A 45-year-old woman in an altered mentality had improved over 1 month. About 1 week after the initial improvement, the patient became comatose with aggravated EEG and MRI findings. Assays of cerebrospinal fluid and serum were positive for the IgM antibody to Japanese-B virus. After intravenous immunoglobulin (IVIG) infusion, the patient recovered. We report a patient with JE who showed a biphasic illness pattern and recovered after IVIG therapy.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10b
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• pp.661-663
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• 2003

In this paper, we present new methods for rapid high-resolution range sensing using green-blue stripe pattern. We use green and blue for designing high-frequency stripe projection pattern. For accurate and reliable range recovery, we identify the stripe patterns by our color-stripe segmentation and unwrapping method. The experimental result for a naked human face shows the effectiveness of our method.

• Journal of Korean Neurosurgical Society
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• v.30 no.4
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• pp.501-508
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• 2001

Objectives : Hemifacial spasm is painless uncommon disorder characterized by involuntary paroxysmal movement on one side of face. It is known that hemifacial spasm is mainly due to pulsatile compression by vessels at the root exit zone(REZ) of the facial nerve. Microvascular decompression at REZ of the facial nerve has become the standard treatment modality for hemifacial spasm. The authors have analized patients with hemifacial spasm treated with microvascular decompression to evaluate operation result and clinical course after operation. Patients and Methods : From 1992 to 1999, 41 patients with hemifacial spasm underwent this operation. Retrospective analysis of operation results and clinical recovery patterns was done. The length of observation had been more than 6 months in all cases. Results : The ratio of male to female was 1:1.4, and age at operation ranged from 24 to 66 years. Their mean age was 47.6 years and the mean preoperative duration of symptoms was 7.2 years. Most common offending vessels were AICA in 18 cases(48%) and second most common were PICA in 13 cases(31.7%). The rest of them were 3 case in vertebral artery, and 7 cases(13%) in multiple offending vessels. Patterns of improvement after surgery could be divided into 4 clinical types. There was complete recovery in 3 days after operation in 24 cases(58.6%, Immediate complete recovery). There was complete recovery in 3 days after operation, and symptom was recurred partially, which was gradually subsided in 2 weeks after operation in 4 cases(9.8%, Delayed complete recovery type I). There was partial recovery after operation and symptom was compretely disappeared gradually in 6 months after operation in 7 cases(17.1%, Delayed complete recovery type II). Finally, there was partial recovery after operation, and symptom was somewhat remained after 6 months later(14.5%, Delayed partial recovery). Conclusion : In conclusion, microvascular decompression for hemifacial spasm is a safe and reliable treatment modality with good results of improvement and there are 4 recovery patterns in clinical course after operation in our series. Therefore, follow-up observation after microvascular decompression is necessary to evaluate the operative results and complication, especially in the delayed resolved cases.

• Journal of the Korean Arthroscopy Society
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• v.13 no.2
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• pp.155-160
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• 2009

Purpose: The purpose of this study was to evaluate the pain recovery pattern according to the integrity and to analyze the factors affecting the progress and level of pain postoperatively. Materials and Methods: We examined 153 patients, who were treated with arthroscopic rotator cuff repair. 101 rotator cuff tears were full-thickness tear and 52 were partial tear. The mean follow up duration was 20 months (12~30 months). We evaluated the visual analogue scale, range of motion, ASES (American Shoulder and Elbow Surgeons), and UCLA (University of California at Los Angeles) scores preoperatively and postoperatively. We analyzed the pain recovery pattern between partial and full thickness tear using Student T-test and the factors affecting the progress and level of postoperative pain using multiple regression analysis. Results: The change patterns of visual analogue scale after arthroscpoic repair were similar regardless of the tear integrity. The VAS showed a continuous decreasing pattern, but increased at first 3 weeks postoperatively and at 7 weeks postoperatively, and then, decreased thereafter. The average VAS was ${\leqq}2$ points by postoperative 3 months. The factor affecting the pain score at 3 months was related to the preoperative limitation in forward flexion ($r^2=0.377$, p=0.021). Conclusion: There was no differences of the pain recovery pattern according to the integrity, and the factor affecting the progress of postoperative pain was preoperative angle of forward elevation. So, the appropriate preoperative rehabilitation protocol that can improve motions of the shoulder joint would help to improve the level of postoperative pain and functional recovery.

• Journal of Veterinary Clinics
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• v.19 no.2
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• pp.125-131
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• 2002

The present experiment was performed in order to know the therapeutic effect of laserpuncture and aquapuncture with methionine on recovery in artificially induced hepatic damaged rats by carbon tetrachloride. The animals were divided into control, laserpuncture and aquapuncture groups. The changes of serum enzyme activities(ALT and AST), serum total protein contents, protein fractions(ALB and GLB) and A/G ratio were examined before and after application of laserpuncture and aquapuncture. In change of serum ALT activity, recovery with treatment in laser and aquapuncture groups was more rapid than that of control. The significant decreased value was shown on 3rd(P < 0.05) and 7th day(P < 0.01) after treatment in laserpuncture group and on 7th day(P < 0.05) after treatment in aquapuncture group. In addition, significance was detected on 2nd day(P < 0.05) between laserpuncture and aquapuncture groups. In change of serum AST activity, recovery with treatment in laserpuncture and aquapuncture groups was more rapid than that of control. The significant lower values on 7th day(P<0.01) in aquapuncture groups. In addition, significant low value was detected on 7th day(P < 0.05) in aquapuncture group comparing with that of laserpuncture group. The change of serum TP contents showed similar pattern in control, laser and aquapuncture groups. The significances were detected on 7th day(P < 0.05) in both experimental groups. In addition, significant high value was detected on 2nd day(P < 0.05) in laserpuncture group comparing with that of aquapuncture group. The change of serum ALB content with treatment in laser and aquapuncture groups was more rapid than that of control. The significant high value was shown on 2nd(P < 0.01), 5th(P < 0.05) and on 7th day(P < 0.01) in laserpuncture group. In addition, significant high value was detected on 3rd day(P<0.01) only in aquapuncture group comparing with laserpuncture group. The change of serum GLB content showed similar pattern among groups. The significant low values were detected on 2nd day(P < 0.05) in aquapuncture group. In addition significant high value was detected on 5th day(P < 0.01) only in laserpuncture group comparing with that of aquapuncture group. In change of A/G ratio laser and aquapuncture groups showed higher values than that of control. The significant high values were detected on 1st day(P < 0.Of) and 2nd day(P < 0.05) in laserpuncture group, and on 1st day(P < 0.05) and 2nd day(P < 0.01) in aquapuncture group. In addition, significant high value was detected on 5th day(P < 0.05) in aquapuncture group comparing with that of laserpuncture. Considering above findings collectively, it was considered that both laserpuncture and aquapuncture were effective; aquapuncture was more effective than laserpuncture for recovery of hepatic damage.