• Journal of Biomedical Engineering Research
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• v.5 no.1
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• pp.5-8
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• 1984

As the ensemble averaged dz/dt signal during exercise gets smoothed, it is difficult to find the distinctive marks for estimation of stroke volume. The cross correlation function was made use of estmating these marks for automatic calculation by computer from the ensemble averaged dz/dt signal. LVET(Left Ventricular Ejection Time) and stroke volume were estimated based on the calculated parameters from the characteristic points. LVET, stroke volume calculated by hand, by the ensemble average and the cross correlation were compared for accuracy validation.

• Journal of Biomedical Engineering Research
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• v.11 no.1
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• pp.65-70
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• 1990

The phenomenon of color sensory has been mainly studied on the relation with the stimulus source of light source color according to dispersed energy of light. However, it has not been definitely found that the phenomenon of color sensory be collcerned with evoked potentials stimulated by object color. This paper proposes the method that evoked potentials stimulated by object colors are analyzed and examined on the phenomemon of color sensory. The model of evoked potentials is assumed that it is consisted of an additive noise and a transient signal caused by stimulus. The method which is used to estimate the signal is time-varying filtering.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.11
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• pp.58-62
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• 1992

Hybrid optical-electronic procedures are introduced for the automated estimation of cell parameters (e.g., size, size variation, and shape). Two different optical Fourier analysis procedures are applied to high contrast cell boundary patterns obtained from specular micrographs of the endothelial layer. In one case, a large number of cell patterns are illuminated to extract average cell size information. Once the average cell size information has been obtained, individual cells are illuminated to extract shape information.

• Journal of the Korean Statistical Society
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• v.34 no.1
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• pp.11-20
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• 2005

The distributional properties of R = X/(X + Y) and related estimation procedures are derived when X and Y are independent and identically distributed according to the Weibull or Levy distribution. The work is of interest in biological and physical sciences, econometrics, engineering and ranking and selection.

• Journal of Biomedical Engineering Research
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• v.6 no.2
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• pp.43-52
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• 1985

In this paper, the depth and attenuation coefficient are estimated from the mutilayered liver tissue which contained a inhomogeneous one using reflected ultrasonic signals and the abnormal one is detected quantitatively. Regarding a liver tissue as several reflectors, we analyzed each one by the frequency spectral difference method and discussed its attenuation characteristics. For the verification of this method, the liver pantom and acryle are used. And also we proved the usefulness through the experiment.

• Journal of Biomedical Engineering Research
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• v.12 no.4
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• pp.261-266
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• 1991

As the ensemble averaged dz/dt signal during exercise gets smoothed, it is difficult to find the distinctive marks for estimation of stroke volume. The cross correlation function was made use of estimating these marks for automatic calculation by computer from the ensemble averaged dz/dt signal. LVET( Left Ventricular Ejection Time) and stroke volume were estimated based on the calculated parameters from the characteristic points. LVET, stroke volume calculated by hand, by the ensemble average and the cross correlation were compared for accuracy validation.

• Proceedings of the KOSOMBE Conference
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• v.1993 no.05
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• pp.74-77
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• 1993

Estimation and removal of power line interference in the electrocardiogram using adaptive noise cancelling techniques is presented. The system identification concepts are used to design the noise cancelling filter and the prediction error method is used to adjust filter coefficients. Computer simulation were performed to compare this method with the Lekov's method.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.79-97
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• 1995

On the basis of the literature, which is at present still scientific information improvable, the results of research done so far into the occurrence and analytical methodology of major markers of environmental tobacco smoke(ETS) have been summarized. Key areas addressed are: differences in physicochemical composition between mainstream smoke, sidestream smoke and ETS: techniques for field measurement of ETS: relationship between indoor air quality with ETS and its distribution view of US EPA and its problems: biological effects and concerning estimation of ETS exposure.

• Journal of the Korea Society for Simulation
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• v.10 no.3
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• pp.31-46
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• 2001

Repeated measurements on units under different conditions are common in biological and biomedical studies. In a number of growth and pharmacokinetic studies, the relationship between the response and the covariates is assumed to be nonlinear in some unknown parameters and the form remains the same for all units. Nonlinear random coefficient models are used to analyze such repeated measurement data. Extended least squares methods are proposed in the literature for estimating the parameters of the model. However, neither objective function has closed form expression in practice. This paper proposes Monte Carlo methods to estimate the objective functions and the corresponding estimators. A simulation study that compare various methods is included.

• Journal of Ecology and Environment
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• v.42 no.2
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• pp.77-84
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• 2018

Background: For understanding and evaluating a more realistic and accurate assessment of ecosystem carbon balance related with environmental change or difference, it is necessary to analyze the various interrelationships between soil respiration and environmental factors. However, the soil temperature is mainly used for gap filling and estimation of soil respiration (Rs) under environmental change. Under the fact that changes in precipitation patterns due to climate change are expected, the effects of soil moisture content (SMC) on soil respiration have not been well studied relative to soil temperature. In this study, we attempt to analyze relationship between precipitation and soil respiration in temperate deciduous broad-leaved forest for 2 years in Gwangneung. Results: The average soil temperature (Ts) measured at a depth of 5 cm during the full study period was $12.0^{\circ}C$. The minimum value for monthly Ts was $-0.4^{\circ}C$ in February 2015 and $2.0^{\circ}C$ in January 2016. The maximum monthly Ts was $23.6^{\circ}C$ in August in both years. In 2015, annual precipitation was 823.4 mm and it was 1003.8 mm in 2016. The amount of precipitation increased by 21.9% in 2016 compared to 2015, but in 2015, it rained for 8 days more than in 2016. In 2015, the pattern of low precipitation was continuously shown, and there was a long dry period as well as a period of concentrated precipitation in 2016. 473.7 mm of precipitation, which accounted for about 51.8% of the precipitation during study period, was concentrated during summer (June to August) in 2016. The maximum values of daily Rs in both years were observed on the day when precipitation of 20 mm or more. From this, the maximum Rs value in 2015 was $784.3mg\;CO_2\;m^{-2}\;h^{-1}$ in July when 26.8 mm of daily precipitation was measured. The maximum was $913.6mg\;CO_2\;m^{-2}\;h^{-1}$ in August in 2016, when 23.8 mm of daily precipitation was measured. Rs on a rainy day was 1.5~1.6 times higher than it without precipitation. Consequently, the annual Rs in 2016 was about 12% higher than it was in 2015. It was shown a result of a 14% increase in summer precipitation from 2015. Conclusions: In this study, it was concluded that the precipitation pattern has a great effect on soil respiration. We confirmed that short-term but intense precipitation suppressed soil respiration due to a rapid increase in soil moisture, while sustained and adequate precipitation activated Rs. In especially, it is very important role on Rs in potential activating period such as summer high temperature season. Therefore, the accuracy of the calculated values by functional equation can be improved by considering the precipitation in addition to the soil temperature applied as the main factor for long-term prediction of soil respiration. In addition to this, we believe that the accuracy can be further improved by introducing an estimation equation based on seasonal temperature and soil moisture.