• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1389-1393
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• 2002

The non-spectroscopic interference effects that occurred in inductively coupled plasma/mass spectrometry were studied for Ge, As and Se in human urine and serum. Many biological samples contain Na, K, Cl and organic compounds, which may cause the enhancement and depression on the analyte signal. The effect of 1% concomitant elements such as N, Cl, S, P, C, Na, and K on a 100 ㎍/L germanium, arsenic and selenium signal has been investigated by ICP/MS. The interference effects were not in the same direction. It appeared that concomitant elements such as Cl, S, and C induce an enhancement effect, whereas N and P did not show any significant effect. And, Na and K caused a depression. We have found a link between the abundance of analytes and the ionization potential of concomitant elements (eV), except carbon and nitrogen.

• KSBB Journal
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• 제13권4호
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• pp.461-467
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• 1998

A fermentation system was supplemented with a device for the measurement of the durations of alkali pump feeding for automatic pH control and an A/D convertor for precise monitoring of pH value by computer. A software program was developed to measure buffer capacities from the pH signal and the pH control signal during fermentation. By measuring the buffer capacity on-line, levels of acetic acid were estimated by a software sensor using pH signal in a fermentation process of E.coli growing in a minimal medium. The measured values of acetic acid showed correlation to those of estimated by the software sensor. Lacitic acid production was also successfully estimated by the values of buffer capacities measured on-line.

• International Journal of Control, Automation, and Systems
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• 제2권1호
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• pp.23-38
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• 2004

We proposed the infinity control principle to evaluate the Biological function. The H infinity control was applied to the Sodium (Na) ion selective gating channel on the excitable cellular membrane of the neural system. The channel opening, closing and inactivation processes were expressed by movements of three gates and one inactivation blocking particle in the channel pore. The rate constants of the channel state transition were set to be voltage dependent. The temporal changes in amounts per unit membrane area of the channel states were expressed by means of eight differential equations. The biochemical mimetic used to complete the Na ion selective channel was regarded as noise. The control inputs for ejecting the blocking particle with plugging in the channel pore were set for the active transition from inactivated states to a closed or open state. By applying the H infinity control, we computed temporal changes in the channel states, observers, control inputs and the worst case noises. The present paper will be available for evaluating the noise filtering function of the biological signal transmission system.

• 한국전자통신학회논문지
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• 제9권4호
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• pp.499-508
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• 2014

본 논문에서는 생체신호인 PPG, GSR 신호의 변화에 따라 구동되는 LED 감성조명 시스템을 구현하였다. 개발된 GSR 및 PPG 센서모듈로부터 인체의 생체신호를 측정하고, 측정된 생체신호를 이용하여 MCU에서 제안된 각성 이완 판별맵에 근거하여 피검자의 각성 또는 이완 상태를 판단한다. 피검자의 상태에 대응하는 LED 조명색상의 변화를 주어, 피검자가 안정 상태의 감정에 도달할 수 있도록 하는 감성조명 시스템을 개발하였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.285-288
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• 2008

In ubiquitous computing environment the biological signal ECG (Electrocardiogram signal) is usually recorded with noise components. Adaptive interference (or noise) canceller do adaptive filtering of the noise reference input to maximally match and subtract out noise or interference from the primary (signal plus noise) input thereby adaptively eliminate unwanted interference from the ECG signal. Measured Stress ECG (or exercise ECG signal) signal have three major noisy component like baseline wander noise, motion artifact noise and EMG (Electro-mayo-cardiogram) noise. These noises are not only distorted signal but also root of incorrect diagnosis while ECG data are analyzed. Motion artifact and EMG noises behave like wide band spectrum signals, and they considerably do overlapping with the ECG spectrum. Here the multidimensional adaptive method used for filtering which is more effective to improve signal to noise ratio.

• Journal of Microbiology
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• 제40권4호
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• pp.305-312
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• 2002

The effects of two natural polyamines (putrescine and spermidine) on the synthesis of ArcA, a response regulator of the Arc two-component signal transduction system, were studied using an E. coli mutant deficient in polyamine biosynthesis. Endogenous polyamine deficiency of the mutant resulted in marked reduction in the ArcA level determined by Western blot analysis. Putrescine supplement to the growth medium effectively increased the ArcA level of the mutant in a concentration-dependent manner. Spermidine also stimulated the ArcA level in the mutant to a greater degree than putrescine. Expression of arcA'::lacZ operon fusion in the mutant was stimulated 6-fold and 10-fold by putrescine and spermidine at a 1mM concentration, respectively, indicating that the stimulatory effect of the polyamines on ArcA synthesis is due to transcriptional induction, and that spermidine is a more potent arcA inducer than putrescine. The polyamine-dependent arcA'::lacZ induction was growth-phase-dependent and independent of either arcA or fnr which are two regulators involved in anaerobic stimulation of the Arch level. These results suggested that putrescine and spermidine polyamines may be potential intracellular signal molecules in the control of arcA expression, and thereby may play an important role in cellular metabolism.

• 반도체디스플레이기술학회지
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• 제20권1호
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• pp.32-36
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• 2021

The number of processes in the manufacture of semiconductors, displays and solar cells is increasing. And as the processes is performed, multiple layers of films and various patterns are formed on the wafer. At this time, substrate warpage occurs due to the difference in stress between each film and pattern formed on the wafer. the substrate warping phenomenon occurs due to the difference in stress between each film and pattern formed on the wafer. We developed a new warpage measurement method to measure wafer warpage during real-time processing. We performed an experiment to measure the presence and degree of warpage of the substrate in real time during the process by adding only measurement equipment for applying additional electrical signals to the existing ESC and detecting the change of the additional electric signal. The additional electrical measurement signal applied at this time is very small compared to the direct current (DC) power applied to the electrostatic chuck whit a frequency that is not generally used in the process can be selectively used. It was confirmed that the measurement of substrate warpage can be easily separated from other power sources without affecting.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
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• pp.58-58
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• 2000

No Abstract, See Full Text

• 대한의용생체공학회:의공학회지
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• 제15권3호
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• pp.281-288
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• 1994

In this paper, a new decomposition method of the interference EMG signal using MAMDF filtering and digital signal processor. The efficient software and hardware signal processing techniques are employed. The MAMDF filter is employed in order to estimate the presence and likely location of the respective templates which may include in the observed mixture, and high-resolution waveform alignment is employed in order to provide the optimal combination set and time delays of the selected templates. The TMS320C25 digital signal processor chip is employed in order to execute the intensive calculation part of the software. The method is verified through a simulation with real templates which are obtain ed from needle EMG. As a result, the proposed method provides an overall speed improvement of 32-40 times.

• 예술인문사회 융합 멀티미디어 논문지
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• 제8권6호
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• pp.957-966
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• 2018

최근 들어 고령화 및 1인 가구 증가로 인해 IoT기반 원격환자모니터링에 대한 요구가 증대되고 있다. 본 논문에서는 원격환자모니터링을 위한 다중의 IR-UWB레이더를 이용한 비접촉식 생체신호측정시스템을 제안하였다. 기존에는 생체신호처리를 위해 배경차분알고리즘을 적용하였으나, 전압노이즈, 계단현상 등의 에러 발생을 없애고자 다중 배경차분 알고리즘을 적용하였다. 다중배경차분알고리즘은 이전 클러터와 현재 클러터의 변화량을 계산하여 신호를 추출하며, 본 연구에서는 SVD알고리즘을 이용하였다. 개선된 다중배경차분알고리즘을 생체신호측정에 응용하여 고속 푸리에 변환을 통해 호흡수를 계산하였다. 제안한 IR-UWB레이더를 이용한 시스템 및 다중배경차분알고리즘의 검증을 위해 호흡수 측정을 진행하였다. Neulog사의 부착형 공기압착식 호흡측정기를 대조군으로 실험한 결과 97.36%의 정밀도를 확보함으로서 본 연구의 타당성을 검증하였다. 구현된 알고리즘은 기존의 접촉식 웨어러블 방식의 불편함을 개선하였다.