• International Journal of Contents
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• 제10권2호
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• pp.47-58
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• 2014

Physiological signals provide important clues in the diagnosis and prediction of disease. Analyzing these signals is important in health and medicine. In particular, data preprocessing for physiological signal analysis is a vital issue because missing values, noise, and outliers may degrade the analysis performance. In this paper, we propose PhysioCover, a system that can recover missing values of physiological signals that were monitored in real time. PhysioCover integrates a gradual method and EM-based Principle Component Analysis (PCA). This approach can (1) more readily recover long- and short-term missing data than existing methods, such as traditional EM-based PCA, linear interpolation, 5-average and Missing Value Singular Value Decomposition (MSVD), (2) more effectively detect hidden variables than PCA and Independent component analysis (ICA), and (3) offer fast computation time through real-time processing. Experimental results with the physiological data of an intensive care unit show that the proposed method assigns more accurate missing values than previous methods.

• Journal of Ecology and Environment
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• 제40권3호
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• pp.136-143
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• 2016

Background: Mussels are stubborn organisms attached to solid substrata by means of byssus threads. The abundance of marine mussel Mytilus edulis in marine facilities like power stations was reason to select among fouling animals. Methods: Mortality patterns as well as physiological behavior (oxygen consumption, foot activity, and byssus thread production) of two different size groups (14- and 25-mm shell length) of M. edulis were studied at different hydrogen peroxide concentrations ($1-4mg\;l^{-1}$). Results: Studied mussels showed progressive reduction in physiological activities as the hydrogen peroxide concentration increased. Mussel mortality was tested in 30 days exposure, and 14 mm mussels reached the highest percentage of 90% while 25 mm mussels reached 81%. Produced data was echoed by Chick-Watson model extracted equation. Conclusions: This study points that, while it could affect the mussel mortality moderately in its low concentrations, hydrogen peroxide has a strong influence on mussels' physiological activities related to colonization. Therefore, hydrogen peroxide can be an alternative for preventing mussel colonization on facilities of marine environment.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 1999년도 춘계학술발표논문집 논문집
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• pp.221-230
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• 1999

Automobile horn's psychoacoustic characteristic and significance as a anturalistic signal of danger makes it a valuable auditory stimulus to study such psychophysiological responses as startle, orienting and defense reactions. However, comparison and differentiation of physiological responses to commercially available horns is a complicated task due to small contrast of technical features of horns and influence of such processes as habituation on physiological outcome with increased number of auditory stimulation trials. In the study on 10 college students we performed comparative analysis of tonic and phasic reactivity of physiological responses mediated by autonomic nervous system in order to identify role of habituation and decrement of autonomic responsivity, as well as possibility o differentiate subjectively most and least preferred and subjectively more appropriate horns according to physiological manifestations. It was showed that electrodermal and cardiovascular reactivity have concurrent patterns of adaptation to repeated stimulation, namely skin conductance variables habituated, cardiac reactivity failed to show signs of habituation, while vascular component of response were facilitated demonstrating marked sensitization. Differentiation of Physiological responses to horns with respect to their subjective rating scores was possible, however electrodermal reactivity was effective only at the first block of trials, while phasic and tonic cardiovascular reactivity differentiate responses during whole course of experiment. There are discussed possible autonomic mechanisms involved in mediation of observed results.

• 대한통합의학회지
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• 제4권3호
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• pp.39-47
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• 2016

PURPOSE : This study attempts to find the effects of water perturbation exercise performed on stroke patients in their physiological cost index and gait ability tests. METHOD : The subjects were 30 stroke patients, water perturbation exercise group was performed 3 day per week, for 40 minutes a day, for a period of eight weeks. The physiological cost index and gait of all subjects were assessed by using the polar, 6 Minute Walk Test (6MWT), and 10 meter Walk Test(10mWT) at pre training and post training. Paired t-test was used to analyze change before and after intervention in group. Pearson's correlation was used to analyze correlation of all variables. RESULT : Water perturbation exercise group showed increased physiological cost index. Water perturbation exercise increased gait ability, showing a significant difference. Showing the correlation between the relatively high amount between physiological cost index and 6 minutes walking test. CONCLUSION : From the result of the study, we found that water perturbation exercise was effective in improving physiological cost index and gait ability. The patient is considered to be used by itself to involve the treatment and the risk of falling from the lowered state into the treatment method for the intensive treatment of stroke patients to be useful in improving the cardiovascular system and ability to walk. Through underwater training for stroke patients in the future on the basis of this study it is considered to require additional clinical studies on the impact on daily living and quality of life of stroke patients.

• 전자공학회논문지D
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• 제35D권7호
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• pp.40-47
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• 1998

This paper presents the physiological signal processing CMOS one chip for transmitting human bodys small electrical signals such as electrocardiogram(EKG) or electromyogram(EMG) and the external system for receiving signals was implemented by the commercial ICs. For simultaneous four-subject four-channel telemetry, a new enfored synchronization techniqeu using infrared bi-directional communication has been proposed. The telemeter IC with the size of 5.1*5.1mm$^{2}$ has the following functions: receiving of command signal, initialization of internal state of all functional blocks, decoding of subject-selection signal, time multiplexing of 4-channel modulated physiological signals, transmitting of telemetry signal to external system and auto power down control. The newly designed synchronized oscillator with low supply voltage dependence in the telemeter IC operates at a supply voltage from 4.6~6.0V and the nonlinearity error of PIM modulator was less than 1.2%F.S(full scale). The power saving block operates at the period of 2.5ms even if the telemetry IC does not receive command signal from external system for a constant time.

• 약학회지
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• 제47권2호
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• pp.104-109
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• 2003

The present paper reviews the notion and comparison of the Korea Food and Drug Administration(KFDA) general pharmacology and the International Conference on Harmonisation (ICH) safety pharmacology. General pharmacology or safety pharmacology is termed the study to determine the potential of a compound to induce adverse pharmacological effects. KFDA general pharmacology studies have been considered an important component in drug safety assessment and these were originally referred to those designed to examine effects other than the primary therapeutics effect of a drug candidate. The KFDA notified the Guideline for General Pharmacology in 1997. Safety pharmacology studies were focused on identifying adverse effects on physiological functions. In the ICH came into place S7A Safety Pharmacology Studies for Human Pharmaceuticals in 2001. A new chemical entity should be assessed for its side effects, initially in those physiological systems which are generally agreed to be the key systems that are essential for life; these "core system" include the central nervous system, cardiovascular system and respiratory system in safety pharmacology studies. These studies should be performed in compliance with Good Laboratory Practice (GLP).

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.95-98
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• 1997

In this paper, several nonlinear system identification theories and the application of these methods to the physiological system are reviewed by extracting significant results from the literature. Methods based on unctional series expansion, parameter estimation, block-oriented models are included. However, there is still considerable debate about the advantages and disadvantages of each approach. This is true primarily because each method has limitations on the types of assumption and interpretation, types of nonlinear elements, etc. This means that user must select an appropriate method and the selection will depend on the problem under investigation.

• 한국콘텐츠학회논문지
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• 제15권7호
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• pp.591-600
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• 2015

최근 건강에 대한 관심이 높아짐에 따라 운동 프로그램을 스스로 학습하고 즐길 수 있는 능동형 피트니스 시스템에 대한 연구가 활발히 진행되고 있다. 본 논문에서는 운동 참여자의 생체신호에서 획득한 생체상태와 운동 정보를 이용하여 개인 수준에 맞는 스피닝 트레이닝 프로그램을 자기 주도 방식으로 학습 및 체험할 수 있게 하는 능동형 스피닝 트레이닝 시스템을 설계하고 구현하였다. 제안 시스템은 운동 참여자의 뇌파와 맥파 신호를 통해 생체 상태를 분석하고, 골격 동작을 실시간 인식하여 검출된 스피닝 동작 일치율과 운동량을 반영하여 운동 참여자에게 적합한 난이도의 스피닝 프로그램을 제공한다. 또한, 가상 스피닝 강사를 통해 올바른 동작을 제시하고 참여자의 동작 일치율에 따라서 난이도를 조절함으로써 운동 효과를 높일 수 있도록 하였다. 다양한 사용자들에 대한 실험을 통해 제안시스템이 비교적 짧은 시간에 유효한 운동 효과를 얻는데 도움이 됨을 확인할 수 있었다.

• 감성과학
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• 제13권2호
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• pp.309-316
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• 2010

본 연구에서는 단순 세정의 개념이 아닌 복합감각 증진 개념의 헬스케어 목욕 시스템을 개발하고자 한다. 헬스케어 감성욕조를 디자인하기 위해 우선 타입별 특성을 고찰하였다. 이를 기반으로 복합감각 자극용 전신 욕조를 개발하였고, 이 전신욕조는 감성자극용 전신욕조 월풀, 시청각 감각 자극 기능이 구비된 욕조 커버, 제어용 소형 PC, 터치패널, DMB 패널, 시각 감성 증진을 위한 칼라 가변형 LED 무드 시스템과 스피커로 구성되어 있다. 제작된 복합감각 증진 개념의 헬스케어 욕조시스템의 특성을 고찰하기 위해서 목욕을 하는 동안 인체 자율신경계에 미치는 영향을 분석하였다. 전반적으로 목욕 상태에서의 심박변이율은 실험 중 교감신경에 비해 부교감신경이 계속 증가하는 것으로 나타났고, 목욕을 시작한지 15분이 경과하면 교감신경이 증가하고 부교감신경이 감소하여, 피험자가 목욕을 한지 15분일 때 가장 편안한 상태를 느끼는 것을 알 수 있었다. 또한 목욕 실험 결과 전후의 혈압이 최고 16mmHg까지 떨어진 것으로 나타났으나 맥박은 증가하였다. 이것은 심장으로부터 혈액의 유출량이 많아져 혈류량이 증가하는 것으로 복합감각 증진용 헬스케어 욕조 시스템을 이용한 목욕이 혈액 순환에 긍정적인 영향을 보였다. 본 연구의 결과를 가지고 복합감각 기능증진 헬스케어 목욕시스템의 사용성과 사용자의 생리분석을 통한 기초결과를 통해서 사용자의 생리변화를 분석함으로써 제품의 사용성과 사용자의 생리적 변화 및 감성 간의 관계를 보다 더 명확하게 밝혀낼 수 있으리라 기대한다.

• 센서학회지
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• 제5권1호
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• pp.43-50
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• 1996

본 논문은 $1.5{\mu}m$ n-well CMOS 공정 기술에 의해 제조된 다중 바이오텔레미트리 시스템의 동작 특성을 기술하였다. 이 시스템은 체내에 삽입된 서로 다른 센서로부터 계측한 생체 정보를 무선으로 전송하여 외부에서 수신하는 것으로 8개의 피측정체로부터 선택된 7개의 생체 신호를 연속적으로 체외로 전송 한다. FM송신기와 센서 인터페이스 회로를 제외한 체내 삽입 시스템은 $4{\times}4mm^{2}$의 크기로 집적화 하였고, 집적 화한 IC는 $3{\times}3{\times}2.5cm$의 하이브리드 패키지에 수용하였다. 이 시스템의 특징은 8개의 피측정체중에서 임의의 피측정체를 선택할 수 있을 뿐 아니라, 외부 시스템의 커맨드 신호와 선택 신호에 의해 체내 삽입된 전원의 ON/OFF가 가능하다. 이와 같은 전원의 간헐적 동작으로 커맨드 수신기 자체의 소비 전력도 줄일 수 있다. 현재 국내에서 개발되고 있는 각종센서를 이 시스템과 결합해서 삽입하면 혈압 ECG, EMG, 체온 등의 생체정보를 측정하고 분석하는데 매우 편리할 것으로 기대한다.