• Journal of Mechanical Science and Technology
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• v.18 no.7
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• pp.1246-1257
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• 2004

The objective of this paper is to characterize dynamic pressure traces measured at self-excited combustion instabilities occurring in two combustion systems of different hardware. One system is a model lean premixed gas turbine combustor and the other a fullscale bipropellant liquid rocket thrust chamber. It is commonly observed in both systems that low frequency waves at around 300㎐ are first excited at the onset of combustion instabilities and after a short duration, the instability mode becomes coupled to the resonant acoustic modes of the combustion chamber, the first longitudinal mode for the lean premixed combustor and the first tangential mode for the rocket thrust chamber. Low frequency waves seem to get excited at first since flame shows the higher heat release response on the lower frequency perturbations with the smaller phase differences between heat release and pressure fluctuations. Nonlinear time series analysis of pressure traces reveals that even stable combustion might have chaotic behavior with the positive maximum Lyapunov exponent. Also, pressure fluctuations under combustion instabilities reach a limit cycle or quasi-periodic oscillations at the very similar run conditions, which manifest that a self-excited high frequency instability has strong nonlinear characteristics.

• Journal of Biomedical Engineering Research
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• v.20 no.4
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• pp.451-459
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• 1999

During the electromyographic evaluation for the diagnosis of neuropathy, presence for site of lesion could be predicted by a detection of denervation potentials such as fibrillation potentials or positive sharp waves in a group of muscles. Unfortunately, since denervation potentials are distinguished by examiner's experience, it is possible to make mistake identifying endplate spikes as a denervation potential. The aim of the study was to extract parameters to make an algorithm for quantitative distinction between denervation potentials and endplate spikes. It will help to minimize the examiner's bias and to localize the site of lesion thus increase the reliability on EMG diagnosis. There types of signals, endplate spike, fibrillation potential and positive sharp wave were obtained from the EDB(extensor digitorum brevis) muscle using then neuropathic patients. Eight parameters such as duration, area, slope, peak-to-peak amplitude, positive peak negative peak amplitude, ratio of positive to negative peak amplitude, and number of phase were extracted and compared. As a results, peak-to-peak amplitude, positive peak amplitude, ratio of positive to negative peak amplitude showed statistically significant differences between endplate spikes and denervation potentials. It was concluded that those parameters could be used to establish an algorithm which will improve the accuracies in automated quantitative EMG diagnosis.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.3
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• pp.356-362
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• 1999

Humans may lose considerable amounts of water and electrolytes from sweat during exercise in a hot climate. Optimal ingestion of fluid-replacement beverages may overcome an obstacle factor of exercise performance in the heat. This study was performed the comparison of heart rate and blood lactate between ingestion of Prunus mume solution and water solution during graded maximal exercise using bicycle ergometer in the heat(ambient temperature of 31-32$^{\circ}C$ and relative humidity of 50-55%). Ten healthy no-heat-acclimatized males participated in the study. Exercise duration until all-out of graded testing in the condition of Prunus mume solution ingestion(786.15$\pm$47.66s) was significantly higher(P＜0.05) than the condition of water ingestion. Heart rate at 4 min during graded testing and recovery phase in the condition of Prunus mume solution ingestion was significantly lower(P＜0.05) than the condition of water ingestion. Blood lactate concentration at 30min of recovery phase after graded maximal exercise in the condition of Prunus mume solution ingestion was significantly lower(P＜0.05) than the condition of water ingestion. Recovery rate of blood lactate concentration at 15 min and 30 min of recovery phase after grated maximal exercise in the condition of Prunus mume solution ingestion was significantly lower(P＜0.05) than the condition of water ingestion. Present results suggested that ingestion of Prunus mume solution showed the positive effects on the cardiorespiratory function and acid-base regulation as compared with ingestion of water during graded maximal exercise and recovery phase in hot environment.

• Women's Health Nursing
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• v.8 no.4
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• pp.538-549
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• 2002

This study was designed to test the effects of a full body massage on uterine contraction, length of labor, type of delivery, and drug intervention for primipara during labor. Data were collected using a quasi-experiment method (nonequivalent control group, pre-post test design) from November 1, 2001 to July 31, 2002. The subjects of this experiment consisted of 28 women in the experimental group and 29 in the control group, out of 57 primipara hospitalized at the U OB & GYN hospital in Inchon. The experimental group was given a 20 minute full body massage for each of the three delivery phases (latent, active, and transition). The control group was given conventional delivery care. Three (3) parameters were analyzed in this experiment. (1) The interval, duration, and strength of uterine contraction, using an electric tocodynamometer (2) The elapsed time for stage 1 and stage 2 labor. (3) The types of deliveries and drug interventions, using postpartum medical records The data collected were analyzed using the repeated measures analysis of variance (ANOVA), t-test, and $x^2$ test of the SPSS program. The results of the experiment are as follows: 1) Uterine contraction interval was significantly reduced (F=3.210, p=.050). Duration of uterine contraction showed significant increase only during the transition phase (t=-2.319, p=.023). Strength of uterine contraction showed no significant difference. 2) Total length of labor was significantly shortened (t=-5.245, p=.000). The length of 1st stage labor was significantly shortened (t=-5.164, p=.000), with latent phase showing (t=-4.709, p=.000), active phase (t=-2.973, p=.005), and transition phase (t=-2.031, p=.047). The length of 2nd stage labor showed no significant difference. 3) The number of natural deliveries were significantly increased ($x^2$=13.127, p=.004). 4) The number of drug interventions were significantly fewer ($x^2$= 4.493, p=.034). In conclusion, this study shows that a full body massage has a significantly positive effect on uterine contraction interval, length of labor, type of delivery, and drug intervention. Therefore, this study suggests that a full body massage be used clinically to help primipara during labor.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.2
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• pp.187-195
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• 2015

The gas explosions in offshore installations are known to be very severe according to its geometry and environmental conditions such as leak locations and wind directions, and a dynamic response of structures due to blast loads depends on the load profile. Therefore, a parametric study has to be conducted to investigate the effects of the dynamic response of structural members subjected to various types of load shapes. To do so, a series of CFD analyses was performed using a full-scale FPSO topside model including detail parts of pipes and equipments, and the time history data of the blast loads at monitor points and panels were obtained by the analyses. In this paper, we focus on a structural dynamic response subjected to blast loads changing the magnitude of positive/negative phase pressure and time duration. From the results of linear/nonlinear transient analyses using single degree of freedom(SDOF) and multi-degree-of freedom(MDOF) systems, it was observed that dynamic responses of structures were significantly influenced by the magnitude of positive and negative phase pressures and negative time duration.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.15 no.1
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• pp.38-43
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• 2012

Purpose: Epstein-Barr virus (EBV) hepatitis is a usually asymptomatic and self-limiting disease in immunocompetent patients. However, the range of severity is wide, and the serological diagnosis is typically difficult until the convalescent phase. Thus, we examined the value of plasma EBV DNA real-time quantitative polymerase chain reaction (RT-qPCR) in EBV hepatitis for the timely diagnosis and the relationship between EBV viral load and clinical severity. Methods: Sixty samples were confirmed as having EBV infection by RT-qPCR with the EBV BALF5 gene sequence. We examined the clinical characteristics of EBV hepatitis by reviewing medical records. Results: The median total duration of fever was 8 days (range: 0-13 days). The mean peak value of aspartate aminotransferase (AST) was $241{\pm}214$ U/L, and the mean peak value of alanine aminotransferase (ALT) was $298{\pm}312$ U/L. There was no correlation between the serum levels of liver enzyme and plasma EBV DNA titer ($p$=0.1) or between median total duration of fever and EBV DNA titer ($p$=0.056). The median age of the EBV VCA IgM-negative group was lower compared with the EBV VCA IgM-positive group in EBV hepatitis (2 years vs. 6 years, $p$=0.0009). Conclusion: The severity of EBV hepatitis does not correlate with circulating EBV DNA load according to our data. Furthermore, we suggest that plasma EBV PCR may be valuable in young infants in whom the results of serology test for EBV infection commonly are negative.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.1
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• pp.45-54
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• 2005

This study was carried out to investigate the patterns of dry matter (DM) production and accumulation, and to screen the relationships between related major growth characters and DM accumulation in four cassava varieties in Bogor $(6^{\circ}19'-6^{\circ}47'S,\;106^{\circ}21'-107^{\circ}13'E)$, West Java, Indonesia. Gading and Adiral developed an enough source and canopy in short at the early growth phase and then translocated assimilates to storage roots with a higher partitioning rate, even these varieties were considered as early-bulking varieties, which have superior source and sink potentials in increasing yield and DM of tubers. The root/shoot ratio (R/SR), total dry weight (TDW), leaf area duration, leaf area index (LAI), and number of tubers showed higher positive correlations with the dry weight of roots (DWR), and the direct effects of TDW, R/SR, and LAI on the DWR were higher. These characters were considered to be useful target characters to screen cassava varieties with high yield potential and high DM in aspect of tuber production.

• Korean Journal of Veterinary Research
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• v.41 no.1
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• pp.89-98
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• 2001

This study was conducted to detect the toxoplasma specific-DNA in circulating blood and organs collected from slaughtered pigs at slaughtering house and experimentally infected pigs with Toxoplasma gondii tachyzoites by polymerase chain reaction(PCR), and also PCR was applied to diagnose for acute phase of swine toxoplasmosis as a newly developed diagnostic test. The sensitivity of oligonucleotide primer, T-1 & T-2, designed from toxoplasma B1 gene amplification method was compared with Tp parasite detection by mouse inoculation(MI). On the other hand, latex agglutination test(LAT) was conducted to detect the serum antibodies comparing with the detection of toxoplasma by PCR and MI. The results obtained were summarized as follows. PCR was able to determine at the lowest level of $10^0/ml$ T. gondii in blood samples which were blended with a serial diluted T gondii in vitro. On the other hand, $10^2/5g$ of T gondii could detect from a variety of tissues including lung, diaphragm, liver, heart, spleen and brain in vitro. The primer was proved to specifically determine T gondii in blood and tissues in vitro but it did not detect Neospora caninum used as a negative control. DNA of T. gondii was effectively extracted by freezing, thawing and grinding twice both tissues mixed with T gondii in vitro and in experimentally infected pig's tissues. PCR detected specific DNA in the blood of experimentally infected pigs at 108 hrs and 120 hrs post-infection, it was the same time that the pigs showed fever and parasitaemia. In case of tissue, specific DNA was, however, detected only lung from experimentally infected pigs. Even though the duration of acute phase was from 3 to 7 days post-infection, but the latex agglutination test (LAT) results appeared from 8 days post-infection. A comparison of sensitivity in determining T gondii in blood samples between PCR and MI, PCR positive rate ranged from 25 to 33.3%, but that of MI covered from 75 to 100%.

• Journal of Acupuncture Research
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• v.24 no.2
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• pp.155-167
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• 2007

Objectives : This study was performed to evaluate the general distribution and the efficacy of oriental medical treatment for low back pain. Methods: We have selected of the moxa bucket moxibustion. We make a comparative study of the thermodynamic characteristics of moxa bucket moxibustion. We examined combustion times, temperatures, temperature gradients in each period during a combustion of moxa bucket moxibustion made by oak wood. Results : The 80 cases of low back pain patients was analyzed according to the distribution of sex, age, the period of disease, contributing factor, the patient-condition on admission, the symptom on admission, the duration of admission, the reading of the X-ray and the treatment efficacy was evaluated respectively. 1. Female was more than male in the ratio of 1:1.2, and thirties and seventies 25% the most, the acutest phase 46.3% the most, reason unknown 33.8% the most, Grade III 50% the most, L.B.P. only 51.3% the most, the day of 6-10 30% the most, compression Fx 30% the most. 2. In the total treatment result, the good was 51.3%, the excellent 22.5%, the fair 17.5%, the poor 8.8% in order. About 'the effective rate'(the percentage of positive effective treatment cases) of each distribution, the fifties 100% the most, the acutest phase 97.3% the most, the slip down, weight lifting, overuse 100% the most respectively, Grade III 97.5% the most, L.B.P. only 95.1% the most, the day of 11-15 100% the most, HN.P. 93.3% the most. Conclusions : We have known the efficacy of oriental medical treatment for L.B.P. was good and early treatment was better than late treatment and main cause of L.B.P. was degenerative change.

• The Korean Journal of Pain
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• v.30 no.1
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• pp.3-17
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• 2017

Background: Postherpetic neuralgia (PHN) is a common and painful complication of acute herpes zoster. In some cases, it is refractory to medical treatment. Preventing its occurrence is an important issue. We hypothesized that applying nerve blocks during the acute phase of herpes zoster could reduce PHN incidence by attenuating central sensitization and minimizing nerve damage and the anti-inflammatory effects of local anesthetics and steroids. Methods: This systematic review and meta-analysis evaluates the efficacy of using nerve blocks to prevent PHN. We searched the MEDLINE, EMBASE, Cochrane Library, ClinicalTrials.gov and KoreaMed databases without language restrictions on April, 30 2014. We included all randomized controlled trials performed within 3 weeks after the onset of herpes zoster in order to compare nerve blocks vs active placebo and standard therapy. Results: Nine trials were included in this systematic review and meta-analysis. Nerve blocks reduced the duration of herpes zoster-related pain and PHN incidence of at 3, 6, and 12 months after final intervention. Stellate ganglion block and single epidural injection did not achieve positive outcomes, but administering paravertebral blockage and continuous/repeated epidural blocks reduced PHN incidence at 3 months. None of the included trials reported clinically meaningful serious adverse events. Conclusions: Applying nerve blocks during the acute phase of the herpes zoster shortens the duration of zoster-related pain, and somatic blocks (including paravertebral and repeated/continuous epidural blocks) are recommended to prevent PHN. In future studies, consensus-based PHN definitions, clinical cutoff points that define successful treatment outcomes and standardized outcome-assessment tools will be needed.