• Journal of Biomedical Engineering Research
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• v.24 no.3
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• pp.175-181
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• 2003

Studies of muscle fatigue have mostly been checked under isometric exercise. However EMG signals from isotonic exercise generate uncontrollable noise, so there were difficulties in gathering reliable median frequency and muscle fatigue index if frequency analysis was equally applied in isometric exercise. This study tried to compare the differences of muscle fatigue determinant variables in terms of median frequency searching methods of EMG signal, which was estimated in isotonic exercise. To accomplish this, we determined median frequency by using different FFT intervals and overlapping ration of consecutive FFT sections under the same EMG signal, and then searched for a linear regression line, and compared initial median frequency, slope, and muscle fatigue index which were variables under the linear regression line. In result of comparison, initial median frequency was more elevated as FFT exercise interval became larger. The slope of the linear regression line showed distinguishable decreasing tendency as FFT intervals were larger and overlapping sections were smaller. Significant tendency of muscle fatigue index in FFT interval was shown by high muscle fatigue index in specific FFT intervals.

• Journal of Nutrition and Health
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• v.45 no.5
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• pp.462-469
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• 2012

We investigated dietary effects of prickly pear cactus (Opuntina ficus-indica) on plasma lipids, platelet aggregation (PA), hemolysis, plasma TBARS and liver enzymes. Twenty eight volunteer diving women in Jeju island had daily 20 g cactus tea containing 27% prickly pear cactus (PPC) powder for 4 weeks, and data for the study subjects were analyzed, on the basis of diagnostic criteria for blood pressure (BP)(${\geq}$ 140/90 mmHg), plasma cholesterol (${\geq}$ 200 mg/dL) and triglyceride (${\geq}$ 150 mg/dL). The subjects with higher BP had higher plasma total cholesterol (TC) and triglyceride (TG) concentrations than those with normal BP. Those with higher TC also had higher TG. Subjects with normal BP or normal TC had higher initial slope of PA than their higher counterpart in BP and TC. PPC intake decreased plasma TG in those with higher BP. PPC intake significantly decreased the elevated initial slope in groups with normal BP, TC, and TG. Hemolysis after PPC intake decreased significantly in all the subjects and plasma TBARS decreased in the subjects with higher plasma TC and higher TG. Glutamic-oxaloacetic transaminase (GOT) significantly increased and total bilirubin significantly decreased in all the subjects after PPC intake. The present study with diving women showed that beneficial effects of short term intake of prickly pear cactus might differ depending on the subject conditions in term of blood pressure, and plasma lipids. However, long term usage of prickly pear cactus may provide preventive effects of cardiovascular diseases to all the population, presumably by hypolipidemic, antithrombotic, and antioxidant actions of its bioactive flavonoids and soluble fiber.

• Journal of Convergence for Information Technology
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• v.9 no.4
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• pp.78-87
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• 2019

The study examined how job satisfaction and pay level can affect on old salary workers over time using longitudinal data and longitudinal data analysis. The KLoSA 6-period panel data was used which contains alternate year from 2006 to 2016. In addition, Gender and Age is also considered as moderating variables. As result, the initial value and the slope of pay level influenced the initial value and the slope of job satisfaction, vice versa. It implicates the two factors of pay level and job satisfaction are interrelated. Based on the results of this study, limitations and suggestions were discussed for further research.

• Women's Health Nursing
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• v.28 no.2
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• pp.123-133
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• 2022

Purpose: This study investigated the trajectory of subjective health status in married postmenopausal women and aimed to identify predictive factors affecting subjective health status. Methods: Data were obtained from women who participated in wave 4 (2012) of the Korean Longitudinal Survey of Women & Families Longitudinal Study and continued to the latest phase (wave 7, 2018). A latent growth model (LGM) was used to analyze data from 1,719 married postmenopausal women in the framework of the ecological system theory. Results: The mean age of the participants at wave 4 was 56.39±4.71 years, and the average subjective health status was around the midpoint (3.19±0.84). LGM analysis confirmed that subjective health status decreased over time (initial B=3.21, slope B=-0.03). The factors affecting initial subjective health were age, body mass index, frequency of vigorous physical activity (microsystem level), marital satisfaction (mesosystem level), and medical service utilization (macrosystem level). Medical service utilization and the frequency of vigorous physical activity were identified as predictive factors affecting the slope in subjective health status. The model fit was satisfactory (TLI=.92, CFI=.95, and RMSEA=.04). Conclusion: This analysis of the trajectory of subjective health status of married postmenopausal women over time confirmed that subjective health is influenced by overall ecological system factors, including the microsystem, mesosystem, exosystem, macrosystem, and chronosystem. Therefore, it is necessary to assess physical activity and support policies promoting access to medical services in order to improve the subjective health status of married postmenopausal women.

• Fibers and Polymers
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• v.7 no.4
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• pp.424-431
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• 2006

Roll drafting, a mechanical operation attenuating fiber bundles to an appropriate thickness, is an important operation unit for manufacturing staple yams. It influences not only the linear density regularity of the slivers or staple yams that are produced, but also the quality of the textile product and the efficiency of the thereafter processes. In this research, the dynamic states of the fiber bundle in the roll drafting zone were analyzed by simulation, based on the mathematical model that describes the dynamic behavior of the flowing bundle. The state variables are the linear density and velocity of the fiber bundles and we simulated the dynamics states of the bundle flow, e.g., the profiles of the linear density and velocity in the draft zone for various values of the model parameters and boundary conditions, including the initial conditions to obtain their influence on the dynamic state. Results showed that the mean velocity profile of the fiber bundle was strongly influenced by draft ratio and process speed, while the input sliver linear density has hardly affected the process dynamics. Velocity variance of individual fibers that could be supposed to be a disturbing factor in drafting was also influenced by the process speed. But the major disturbance occurred due to the velocity slope discontinuity at the front roll, which was strongly influenced by the process speed. Thickness of input sliver didn't play any important role in the process dynamics.

• Atmosphere
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• v.17 no.4
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• pp.349-364
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• 2007

The main purpose of this study is to examine the sensitivity of the WRF (Weather Research and Forecasting) in the wind field to the steepness of mountains in the case with a strong downslope wind occurred in the Yeongdong province. We conducted WRF simulations for February 13 2006. The initial and boundary data are from the NCEP/NCAR $1^{\circ}{\times}1^{\circ}$ GDAS. Arbitrary terrains of the mountains with a symmetric orography and an asymmetric one with steeper leeward slope, were introduced to examine the sensitivity of the shape of the mountains. The simulation with an asymmetric terrain results in stronger maximum surface wind by about $10ms^{-1}$ than with a symmetric terrain, especially in the narrow region from the peak to ~ 4 km away in the downstream. However, the maximum surface wind speed is weaker by $20ms^{-1}$ than with a symmetric terrain away from the narrow peak region. This indicates that the steeper slope leads to the intensification of downslope wind in the narrower region leeward. In addition, for the simulation with an asymmetric terrain, the strength of wave breaking is greater and the Lee wave is more dominant than for that with a symmetric terrain.

• The Korean Journal of Nuclear Medicine
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• v.1 no.2
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• pp.75-84
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• 1967

$^{131}I$-labeled-O-iodohippurate renograms in 15 cases of epidemic hemorrhagic fever(E.H. fever)during oliguric, diuretic and convalescent phase were analysed quantitatively and qualitatively, namely by its configuration, Tmax T 1/2 and renal index of Hirakawa. The results were as following: 1) Changes on the renograms in E.H. fever showed simultaneous bilateral renal impairment. 2) The characteristic configurations of renogram in the oliguric phase were: (1) Moderately decreased absolute amplitude of initial spike. (2) Continous rising second slope. (3) No appearance of terminal descent. Those were mast likely to those of renograms in acute ureteral obstruction or acute dehydration state. 3) During the diuretic phase, the renogram showed the point of maximal amplitude, but the steepness of 2nd slope was markedly decreased. The appearance of terminal descents was observed with unusually high amplitude despite of the tremendously large amount of urinary output during this phase. 4) In convalescence, the renograms were essentially normal in configuration, but the renal index of Hirakawa was not recovered until this phase. 5) Renograms in E.H. fever showed the characteristic patterns in each phase of its clinical course. 6) $^{131}I$-OIH-Renogram might be an useful method for the evaluation of renal function in E.H. fever during its course.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.102-109
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• 1998

This study was conducted to find out the growth characteristic of mixed-seeding in the grasses for slope revegetation measures. Seeding treatment with six combination types of five grasses used for this experiment such as orchardgrass(Dactylis glomerata 'Potomac'), perennial ryegrass(Lolium perenne 'Manhattan'), tall fescue(Festuca arundinacea 'Jaguar'), kentucky bluegrass(Poa pratensis 'Majestic') and weeping lovegrass(Eragrostis curvula). The growth of orchardgrass, perennial ryegrass and tall fescue were good on mixed-seeding condition in case of number of individuals, heights and coverages at this experiment. These plants will useful for revegetation measures mixed-seeding, but weeping love grass and kentucky bluegrass did not show a desirable growth in mixed-seeding condition, and these plant prefered mixed seeding to single seeding. Regeneration percents of orchardgrass, perennial ryegrass and tall fescue were higher than that of weeping love grass and kentucky bluegrass, and coverage kept on good condition through one year after seeding, therefore, these plants will effective for initial stage revegetation measures.

• MALSORI
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• no.60
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• pp.67-84
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• 2006

The purpose of this study is to find some acoustic parameters on frequency domain to distinguish the Korean nasals, $/m,\;n,\;{\eta}/$ from each other. The new parameters are devised on the basis of LTAS (Long Term Average Spectrum). The maximum peak amplitude and the relevant formant frequency are measured in low and high frequency range, respectively. The frequency of spectral valley and its energy level are also obtained in the specific frequency range of the spectrum. Spectral slope, total energy value in specific frequency range, statistical distribution of spectral energy like centroid, skewness, and kurtosis are suggested as new parameters as well. The parameters that show statistically significant differences across nasals are summerized as follows. 1) in syllable initial positions: the total energy value from 1,500 to 2,200 Hz(zeroENG); 2) in syllable final positions: the peak amplitude of the first formant(peak1_a), the formant frequency with maximum peak amplitude from 4,000 to 8,000 Hz(peak2_f), the maximum peak amplitude of the formant frequency from 4,000 to 8,000 Hz(peak2_a), and the total energy value from 1,500 to 2,200 Hz(zeroENG).

• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.2
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• pp.159-170
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• 2023

In the present study, the dynamic behavior characteristics of an amphibious assault vehicle during water entry were analyzed using STAR-CCM+, a commercial computational fluid dynamics(CFD) code. All computations were performed using an overset mesh system and a RANS based flow-solver coupled with dynamic fluid-body interaction(DFBI) solver for simulating three degrees of freedom motion. For numerical validation of the solver, a water entry simulation of inclined circular cylinder was conducted and it was compared between an existing experiment data and CFD results. The pitch angle variation and the trajectory of the circular cylinder during water entry shows good agreement with previous experimental and numerical studies. For the water entry simulations of the amphibious assault vehicle, the analysis of dynamic behaviors of the amphibious assault vehicle with different slope angles, submerged depths and initial velocities were conducted. It is confirmed that the steep slope angle increases the submerged volume of the amphibious assault vehicle, so the buoyancy acting on the vehicle is increased and the moved distance for the re-flotation is decreased. It is also revealed that the submerged volume is increased, bow-up phenomenon occur earlier.