• 센서학회지
• /
• 제13권5호
• /
• pp.383-391
• /
• 2004

In this study, we implemented the pulse transit time (PTT) system to examine usefulness of the monitoring method of distensibility and elasticity using photoplethysmography sensor in vivo. PTT is defined as the time interval between the peak of QRS complex in ECG signal and the maximum slope point of photoplethysmography. these two signals were converted to digital data by means of AID converter, then PTT was evaluated by heartbeat using PC. Results of analysis were displayed as a graph using spline interpolation method. The variance of PTT was measured repetitiously to verify efficiency of PTT system in resting state and hyperemic state. Repeated measurement of PTT was not same value but showed that coefficients of correlation were related with each other as 0.8302 (P<0.01) in resting state. And also repeated measurement of PTT showed significant correlation as 0.868 (P<0.01) in the hyperemic state. These result showed that PTT is reflect on transient pressure variance in the artery and is very useful method for the evaluation of prognosis of the hypertension and arteriosclerosis.

• 한국자기학회지
• /
• 제15권6호
• /
• pp.307-310
• /
• 2005

요골동맥의 운동에 대한 공간적 맥진파형 특징을 얻기 위해 2차원 배열 자기터널접합(magnetic tunnel junction; MTJ) 센서를 이용하여 공간 맥진파형 진단장치(spatial pulse diagnostic apparatus; SPDA)를 설계하였다. 자극배열의 위치변동에 대한자장 분포의 변화는 2차원 자기장 유한요소해석 소프트웨어(finite element method magnetics; FEMM)를 사용하여 모의실험을 하였다. 그 결과 평행한 자극배열에서 높은 감도와 균일한 자기장 분포를 얻을 수 있다. 또한 자석배열의 공간 변위 변화는 MTJ 센서의 출력신호 변화와 비례하였다.

• 동의생리병리학회지
• /
• 제17권5호
• /
• pp.1147-1150
• /
• 2003

Modern Objectification of Pulse Diagnosis, One of the Four Diagnosis Method of Oriental Medicine, is necessarily project to improving Oriental medical clinic status and quality by standardization of diagnosis database. At that, accurate measurement equipment or devices(sensor, system and instruments, etc,) to exactly detect MacSang(脈診 : the parameter and subject of pulse diagnosis) have not developed yet. Existing Pulse diagnosis devices are not satisfy clinical needs and medical equipments quality. We study for pulse diagnosis system, that CD is satisfying oriental medical clinic needs, is ensuring accuracy and reappearance to support in clinical diagnosis and treatment, is guaranteeing the quality of medical equipments. theoretical base and convenience.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2006년도 가을 학술발표논문집 Vol.33 No.2 (D)
• /
• pp.719-722
• /
• 2006

무선 센서 네트워크는 센서 노드가 센싱한 정보를 무선 네트워크를 통해서 싱크 노드에게 전달한다. 지금까지의 센서 네트워크는 에너지 소모를 최소화하기 위한 연구가 주로 진행되어 왔다. 그러나 데이터를 수집하는 싱크 노드의 이동성이 보장된다면 더욱 다양한 서비스를 제공할 수 있다. PULSE 프로토콜은 센서 네트워크상에서 에너지 효율적으로 경로를 설정하는 프로토콜이다. 본 논문에서는 기존의 PULSE 프로토콜의 펄스 플러딩 사이에 네트워크 일정 범위 내의 플러딩이 가능하도록 수정한 인터 펄스 플러딩을 추가하여 싱크 노드의 이동성을 지원하고 에너지 효율성도 높인 M-PULSE 프로토콜을 제안한다.

• 한국지능시스템학회논문지
• /
• 제17권5호
• /
• pp.619-625
• /
• 2007

블루투스, 지그비, RFID와 같은 저가의 저 전력 무선통신 기술의 실용화는 웰빙 바람과 함께 유비쿼터스 헬스케어에 대한 관심이 급격하게 증가하고 있으며 u-Health는 센서네트워크분야에서 가장 중요한 응용분야중 하나가 되고 있다. 특히 독거노인이나 실버타운의 노인을 위해 응급상황에 대한 대처가 가능한 의료서비스를 개발하는 것은 그 자체로 의미가 있으며 그 수요는 노령인구의 급속한 증가와 함께 지속적으로 늘어날 것으로 기대된다. 이에 본 논문은 일상생활에서 손가락에 착용한 반지모양의 pulse oximeter 센서에 의해 수집된 PPG 신호로부터 정확한 맥박 변화율을 이끌어내는 것에 대한 타당성을 보이고자 한다. 이를 위해 반사형과 투과형 2가지 종류의 반지센서를 제작하였으며 반지센서로부터 맥박데이터를 수집, 분석하고 응급상황에 대처할 수 있는 원격의 모니터링 시스템을 개발하였다.

• Journal of Electrical Engineering and Technology
• /
• 제2권1호
• /
• pp.136-141
• /
• 2007

The Purpose Of This Paper Is To Use A Tactile Sensor To Compensate The Error Rate. Most Automated Sphygmomanometers Use The Oscillometric Method And Characteristic Ratio To Estimate Systolic And Diastolic Blood Pressure. However, Based On The Fact That Maximum Amplitude Of The Oscillometric Waveform And Characteristic Ratio Are Affected By Compliance Of The Aorta And Large Arteries, A Method To Measure The Artery Stiffness By Using A Tactile Sensor Was Chosen In Order To Integrate It With The Sphygmomanometer In The Future Instead Of Using Photoplethysmography. Since Tactile Sensors Have Very Weak Movements, Efforts Were Made To Maintain The Subject's Arm In A Fixed Position, And A 40hz Low Pass Filter Was Used To Eliminate Noise From The Power Source As Well As High Frequency Noise. An Analyzing Program Was Made To Get Time Delay Between The First And Second Peak Of The Averaged Digital Volume Pulse(${\Delta}t_{dvp}$), And The Subject's Height Was Divided By ${\Delta}t_{dvp}$ To Calculate The Stiffness Index Of The Arteries($Si_{dvp}$). Regression Equations Of Systolic And Diastolic Pressure Using $Si_{dvp}$ And Mean Arterial Pressure(Map) Were Computed From The Test Group (60 Subjects) Among A Total Of 121 Subjects(Age: $44.9{\pm}16.5$, Male: Female=40:81) And Were Tested In 61 Subjects To Compensate The Error Rate. Error Rates Considering All Subjects Were Systolic $4.62{\pm}9.39mmhg$, And Diastolic $14.40{\pm}9.62mmhg$, And Those In The Test Set Were $3.48{\pm}9.32mmhg,\;And\;14.34{\pm}9.67mmhg$ Each. Consequently, Error Rates Were Compensated Especially In Diastolic Pressure Using $Si_{dvp}$, Various Slopes From Digital Volume Pulse And Map To Systolic-$1.91{\pm}7.57mmhg$ And Diastolic $0.05{\pm}7.49mmhg$.

• 한국전기전자재료학회논문지
• /
• 제33권5호
• /
• pp.350-354
• /
• 2020

In this study, a pressure sensor for each displacement was fabricated based on the silicon-based pressure sensor obtained through simulation results. Wires were bonded to the pressure sensor, and a piezoresistive pressure sensor was inserted into the printed circuit board (PCB) base by directly connecting a micro-electro-mechanical system (MEMS) sensor and a readout integrated circuit (ROIC) for signal processing. In addition, to prevent exposure, a non-conductive liquid silicone was injected into the sensor and the entire ROIC using a pipette. The packaging proceeded to block from the outside. Performing such packaging, comparing simple contact with strong contact, and confirming that the measured pulse wavelength appears accurately.

• 한국토양비료학회지
• /
• 제31권2호
• /
• pp.85-94
• /
• 1998

물의 높은 유전율을 이용하여 토양 수분함량을 검정하고저 피복 절연 철봉을 토양에 박아 두 극으로 하는 토양 매질 콘덴서에 RC발진회로를 적용하여 주기를 조사하거나 또는 10 mega Herz Pulse 투여시 최대 저장(貯藏) 전압을 검정하는 방식으로 수분 변화에 따른 토양의 유전율을 조사하였다. 주기식 쎈서에선 토양 콘덴서의 용량이 영점 조정후 표준 콘덴서에 비교된 백분율로 출력되었는데 쎈서봉을 물에 담근 깊이와 선형적 관계에 있었다. 여러 개의 쎈서를 가까운 거리에 설치하면 쎈서봉이 안테나 역할을 하여 RC 발진에 교란이 있었으며 변온에 따른 출력 보정 함수를 제시했다. 토양 수분 함량과 출력사이에 높은 상관성이 있으나 쎈서 붕이 설치된 깊이 및 방향에 따라 출력반응이 변화하므로 사용자가 설치후 출력을 토양수분으로 변환하는 함수를 구하여야 한다. 전압식 쎈서에선 출력이 토양수분 함량과 역함수적 관계에 있어 토양 수분 정밀 계측용으론 적합치 않으나 구성 부품이 적고 노화가 느리어 토양 수분의 간이 검정에 적합하고 출력 전압에 따라 relay를 개폐하되 개폐 전압을 사용자가 설정할 수 있는 회로를 첨부하여 수위 조절 또는 토양수분에 따른 관개 line개폐에 활용한 결과 재현성이 우수하였다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2005년도 ICCAS
• /
• pp.834-837
• /
• 2005

In this paper, we describe the method of non-invasive blood pressure measurement using pulse wave transit time(PWTT). PWTT is a new parameter involved with a vascular that can indicate the change of BP. PWTT is measured by continuous monitoring of ECG and pulse wave. No additional sensors or modules are required. In many cases, the change of PWTT correlates with the change of BP. We measure pulse wave using the photo plethysmograph(PPG) sensor in an earlobe and we measure ECG using the ECG monitoring device our made in the chest. The measurement device for detecting pulse wave consists of infrared LED for transmitted light illumination, pin photodiode as light detector, amplifier and filter. We composed 0.5Hz high pass, 60Hz notch and 10Hz low pass filter. ECG measurement device consists of multiplexer, amplifier, filter, micro-controller and RF module. After amplification and filtering, ECG signal and pulse wave is fed through micro-controller. We performed the initial work towards the development of ambulatory BP monitoring system using PWTT. An earlobe is suitable place to measure PPG signal without the restraint in daily work. From the results, we can know that the dependence of PWTT on BP is almost linear and it is possible to monitoring an individual BP continuously after the individual calibration.

• International journal of advanced smart convergence
• /
• 제2권1호
• /
• pp.1-5
• /
• 2013

This study proposes a remote monitoring of patients and emergency notification system with a camera and pulse wave sensor for U-Healthcare. The proposed system is a server client model based U-Healthcare system which consists of wireless clients that have micro-controller, embedded-board for patient status monitoring and a remote management server. The remote management server observes the change of pulse wave data individually in real-time sent from the clients that is to be remote-monitored based on the pulse wave data stored by users and divides them into caution section and emergency section. When the pulse wave data of a user enters an emergency situation, the administrator can make a decision based on the real-time image information and pulse rate variability. When the status of the monitored patient enters the emergency section, the proposed U-healthcare system notifies the administrator and relevant institutions. An experiment was conducted to demonstrate the pulse wave recognition of the proposed system.