• Environmental Analysis Health and Toxicology
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• v.23 no.4
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• pp.257-265
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• 2008

Nanotechnology is emerging as one of the key technologies of the 21 st century and is expected to enable one to broaden the applicability across a wide range of sectors that can benefit public and improve industrial competitiveness. Already, consumer products containing nanomaterials are available in markets including coatings, computers, clothing, cosmetics, sports equipment and medical devices. Recently, Institute of Occupational Medicine in UK reported an occupational hygiene review for nanoparticles in the viewpoint of nanotoxicity. They reported that the exposure control is very important issues in workplace for exposure assessment, but no proper methods are available to measure the extent of exposures to nanoparticles in the workplace. Therefore, for the estimation of exposure of nanomaterials, we have to approach the material-balance methodology, which similarly carried out in TRI (toxic release inventory) for hazardous chemicals. In order to use this methodology, the exposure source of nanomaterials should be determined firstly. Therefore, herein we investigated the main sources and processes for the exposure to nanomaterals by conducting the survey. The results could be used to define and assess nanohazard sources.

• Communications for Statistical Applications and Methods
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• v.3 no.3
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• pp.179-186
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• 1996

Bioequivanence models arise typically in bioassays when new preparations are compared against standard ones by means of responses on some biological organisms. Relative potency measures provide nice interpretations for such bioequivalence and their estimation constitutes the prime interest of such studies. A conditional quantile process based on the k-nearest neighbor method is proposed for this purpose. An alternative procedure based on Kolmogrov-Smirnov type estimator has also been considered along with. ARIC ultrasound data are analyzed as examples.

• Journal of Biomedical Engineering Research
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• v.14 no.1
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• pp.1-8
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• 1993

In this study, the extractions of formants and articulatory motion trajectories for Korean complex vowels are performed by using the RLSL adaptive linear prediction filter. This enables us to extract accurate spectrum in transition of speech signal. This study shows that the RLSL algorithm is superior to the Levinson algorithm, specially in transition part of speech.

• Environmental Analysis Health and Toxicology
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• v.14 no.3
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• pp.103-111
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• 1999

To effectively predict the lipophilicity, the aryl hydrocarbon receptor (AhR) affinity, and TEF (Toxic equivalency factor) of dioxins by geometrical descriptors, the multiple linear regression methods with the forward selection and backward elimination were employed with statistical validity. The lipophilicity, the Ah receptor binding affinity, and the toxic equivalency factor of dioxins could be predicted using some geometrical descriptors.

• Journal of Biomedical Engineering Research
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• v.3 no.1
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• pp.55-58
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• 1982

In this paper, a method for camera position estimation in gaster using elechoendoscopic image sequence is proposed. In order to obtain proper image sequences, the gaster in divided into three sections. It is presented that camera position modeling for 3D information extraction and image distortion due to the endoscopic lenses is corrected.The feature points are represented with respect to the reference coordinate system belpw 10 percents error rate. The faster distortion correction algorithm is proposed in this paper. This algorithm uses error table which is faster than coordinate transform method using n-th order polynomials.

• Journal of Biomedical Engineering Research
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• v.7 no.1
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• pp.41-44
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• 1986

The objective of tissue characterization is to provide quantitative information about the physical state of tissue interrogated by an ultrasound beam. In the computer simulation, it was found that the echoes were composed of the interferences of the ultrasonic waves reflected from both sides of the thin object, and could be separated by the spectral correlation method. Also, the phantom study demonstrates that thickness of the thin acryl layer beyond the resolution of common ultrasonic imaging systems can be measured- using this method.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06a
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• pp.25-26
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• 2007

• Journal of Biomedical Engineering Research
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• v.10 no.3
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• pp.303-308
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• 1989

A new estimationn mothod of single-EP(evoked potential) using adaptive algorithm and paralnetrlc model is proposed. Since the EEG(eletroencephalogram) signal is stationary in short time interval the AR(autoregressive) parameters of the EEG are estimated by the Burg algorithm using the EEG of prestimulus interval. After stimulus, the single-EP is estimated by adaptive algorithm. The validity of this method is verified by the simulation for generated auditory single-EP based on parametric model.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.05
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• pp.79-81
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• 1992

This paper describes the design of an adaptive closed circuit anesthesia controller based on a multiplexed mass spectrometer system. The controller deals with measurement deterioration caused by measurement delay and rise time through a tong catheter as well as long sampling times due to the multiplexed measurements. Measurement data is extrapolated between sampling periods to increase the estimation convergence rate. A multiple-step-ahead predictive control algorithm is used to calculate intermediatc control inputs between sampling intervals. Simulations are used to validate the designed controller.

• 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.