This document provides an overview of wearable photoplethysmographic sensors. It discusses how PPG sensors use light-emitting diodes and photodetectors to noninvasively monitor pulse rate through optical detection of blood volume changes. Recent advances have enabled the use of high-intensity green LEDs for PPG. The document reviews the history of PPG and developments in wearable pulse rate sensors. Examples of wearable PPG devices include earbud, ring, wristwatch, and forehead sensors. PPG offers a simple, reliable, and low-cost means of monitoring pulse rate.
Wearable photoplethysmographic SensorsV!vEk@nAnD S
This presentation gives the need of wearable photoplethysmographic sensors and how it is benefit to the clinical labs in determining a very range of clinical parameters like pulse rate.
Heamodynamic Monitoring System Using Photoplethysmographyabhijith prabha
A proposed system for combining pulse oximeter and blood pressure measuring apparatus to a single novel device. System will be using optical method, photoplethysmography (PPG) for taking the measurement, thus foolproof and hazard free method introduced.
Problems in Getting Ambulatory Blood Pressure Monitoring using Infrared PPGIJSRD
In the current study, a non-invasive technique for blood pressure (BP) measurement based on the detection of Photoplethysmographic (PPG) pulses during pressure-cuff deflation was compared to sphygmomanometryâ€â€the Korotkoff sounds technique. The PPG Senor used to measure blood pressure using the technique of correlation of volume and pressure. The performance of portable and wearable biosensorsis highly influenced by motion artifact, artery stiffness, measurement sites, light wavelength, sensor pressure, A novel real time system is proposed for accurate motion-tolerant extraction of heart rate (HR) and pulse oximeter oxygen saturation (SpO2) from wearable Photoplethysmographic (PPG) biosensors. Recently, monitoring of blood pressure fluctuation in the daily life is focused on in the hypertension care area to predict the risk of cardiovascular and cerebrovascular disease events. The main problem is using with digital BP monitoring machine is Doctors are not believe on digital machines they believe with only sphygmomanometer. In this paper, in order to propose an alternative system to the existed ambulatory blood pressure monitoring (ABPM) sphygmomanometer, to sort out the problems using small wearable device consisting of photoplethysmograph (PPG) sensors. Recent advances in optical technology have facilitated the use of high-intensity green LEDs for PPG, increasing the adoption of this measurement technique. In this paper, we briefly present the problems of PPG sensor and recent developments in wearable pulse rate sensors with green LEDs.
A review on different technical specifications of respiratory rate monitorseSAT Journals
Abstract Respiratory Rate (RR) is a very important physiological parameter to be monitored in both healthy and critical condition, as it gives meaningful information regarding their respiratory system performance as well as condition. Respiratory rate is an important vital sign that can indicate progression of illness but to also predict rapid decline in health. For the purpose, non-invasive monitoring systems are becoming more popular due to the self-evident increase in patient comfort. It can be hard to predict respiratory failure as it can lead to life threatening condition within a short span of time. Thus it necessitates continuous monitoring of respiratory activity and suitable monitoring equipment are developed which could be life-saving. The survey incorporates non-obtrusive strategies and gadgets used to give data about respiratory rate. Many types of respiratory rate monitors have been used for the measurement of the Respiration Rate. This review consists of seven types of Respiration Rate monitors with different sensors. Respiration Rate monitor using Ultrasonic Sensor and Respiration Rate monitor using facial tracking method are the non-contact respiration rate monitoring system. Respiration Rate measurement based on Impedance Pneumography and Respiration Rate measurement are based on the Thoracic Expansion measurement include the sensor that are placed on the thorax. Respiration Rate monitor with MEMS based Capacitive Pressure Sensor, Respiration Rate monitor with temperature sensor, Respiration Rate meter–a low–cost design approach uses sensors that are mounted within the oxygen mask. Thus the Respiratory Rate Monitors discussed in this paper provide optimal result to detect changes in the severity of chronic illnesses. Keywords: Respiratory Rate, RSA, RSS, Doppler Effect, Movement, Respiratory sensor belt.
Development of a Respiration Rate Meter –A Low-Cost Design Approachhiij
Measurement of physiological parameters like respiration rate is crucial in field of medicine. Respiration
rate can indicate the state of rhythmic behaviour of heart and proper gaseous exchange in blood. As per
Medical research, respiratory rate is regarded as the marker of pulmonary dysfunction. Respiration rate
meters are used in measuring CO2 in expired air and in apnea detectors. It is also used in daily
physiological tests like stress-o-meter for assessing ones level of stress that he/she can perceive in life after
monitoring respiration rate, pulse rate and heart rate. This paper shed lights on the development of a lowcost
respiration rate meter using infrared sensing and associated digital electronic circuitry. The proposed
device is able to measure respiration rate in the range of 0-999 respirations/minute.
Advanced MRI Imaging Combined with Intraoperative MRI for Brain TumorsAllina Health
By Mahmoud Nagib, MD, and Mark Oswood, MD, PhD. How neurosurgeons and radiologists at Abbott Northwestern are using functional MRI, intraoperative MRI and diffusion tensor imaging to improve brain tumor care and enhance patient outcomes.
Wearable photoplethysmographic SensorsV!vEk@nAnD S
This presentation gives the need of wearable photoplethysmographic sensors and how it is benefit to the clinical labs in determining a very range of clinical parameters like pulse rate.
Heamodynamic Monitoring System Using Photoplethysmographyabhijith prabha
A proposed system for combining pulse oximeter and blood pressure measuring apparatus to a single novel device. System will be using optical method, photoplethysmography (PPG) for taking the measurement, thus foolproof and hazard free method introduced.
Problems in Getting Ambulatory Blood Pressure Monitoring using Infrared PPGIJSRD
In the current study, a non-invasive technique for blood pressure (BP) measurement based on the detection of Photoplethysmographic (PPG) pulses during pressure-cuff deflation was compared to sphygmomanometryâ€â€the Korotkoff sounds technique. The PPG Senor used to measure blood pressure using the technique of correlation of volume and pressure. The performance of portable and wearable biosensorsis highly influenced by motion artifact, artery stiffness, measurement sites, light wavelength, sensor pressure, A novel real time system is proposed for accurate motion-tolerant extraction of heart rate (HR) and pulse oximeter oxygen saturation (SpO2) from wearable Photoplethysmographic (PPG) biosensors. Recently, monitoring of blood pressure fluctuation in the daily life is focused on in the hypertension care area to predict the risk of cardiovascular and cerebrovascular disease events. The main problem is using with digital BP monitoring machine is Doctors are not believe on digital machines they believe with only sphygmomanometer. In this paper, in order to propose an alternative system to the existed ambulatory blood pressure monitoring (ABPM) sphygmomanometer, to sort out the problems using small wearable device consisting of photoplethysmograph (PPG) sensors. Recent advances in optical technology have facilitated the use of high-intensity green LEDs for PPG, increasing the adoption of this measurement technique. In this paper, we briefly present the problems of PPG sensor and recent developments in wearable pulse rate sensors with green LEDs.
A review on different technical specifications of respiratory rate monitorseSAT Journals
Abstract Respiratory Rate (RR) is a very important physiological parameter to be monitored in both healthy and critical condition, as it gives meaningful information regarding their respiratory system performance as well as condition. Respiratory rate is an important vital sign that can indicate progression of illness but to also predict rapid decline in health. For the purpose, non-invasive monitoring systems are becoming more popular due to the self-evident increase in patient comfort. It can be hard to predict respiratory failure as it can lead to life threatening condition within a short span of time. Thus it necessitates continuous monitoring of respiratory activity and suitable monitoring equipment are developed which could be life-saving. The survey incorporates non-obtrusive strategies and gadgets used to give data about respiratory rate. Many types of respiratory rate monitors have been used for the measurement of the Respiration Rate. This review consists of seven types of Respiration Rate monitors with different sensors. Respiration Rate monitor using Ultrasonic Sensor and Respiration Rate monitor using facial tracking method are the non-contact respiration rate monitoring system. Respiration Rate measurement based on Impedance Pneumography and Respiration Rate measurement are based on the Thoracic Expansion measurement include the sensor that are placed on the thorax. Respiration Rate monitor with MEMS based Capacitive Pressure Sensor, Respiration Rate monitor with temperature sensor, Respiration Rate meter–a low–cost design approach uses sensors that are mounted within the oxygen mask. Thus the Respiratory Rate Monitors discussed in this paper provide optimal result to detect changes in the severity of chronic illnesses. Keywords: Respiratory Rate, RSA, RSS, Doppler Effect, Movement, Respiratory sensor belt.
Development of a Respiration Rate Meter –A Low-Cost Design Approachhiij
Measurement of physiological parameters like respiration rate is crucial in field of medicine. Respiration
rate can indicate the state of rhythmic behaviour of heart and proper gaseous exchange in blood. As per
Medical research, respiratory rate is regarded as the marker of pulmonary dysfunction. Respiration rate
meters are used in measuring CO2 in expired air and in apnea detectors. It is also used in daily
physiological tests like stress-o-meter for assessing ones level of stress that he/she can perceive in life after
monitoring respiration rate, pulse rate and heart rate. This paper shed lights on the development of a lowcost
respiration rate meter using infrared sensing and associated digital electronic circuitry. The proposed
device is able to measure respiration rate in the range of 0-999 respirations/minute.
Advanced MRI Imaging Combined with Intraoperative MRI for Brain TumorsAllina Health
By Mahmoud Nagib, MD, and Mark Oswood, MD, PhD. How neurosurgeons and radiologists at Abbott Northwestern are using functional MRI, intraoperative MRI and diffusion tensor imaging to improve brain tumor care and enhance patient outcomes.
PHONOCARDIOGRAM-BASED DIAGNOSIS USING MACHINE LEARNING: PARAMETRIC ESTIMATION...bioejjournal
The heart sound signal, Phonocardiogram (PCG) is difficult to interpret even for experienced
cardiologists. Interpretation are very subjective depending on the hearing ability of the physician. mHealth
has been the adopted approach towards quick diagnosis using mobile devices. However, it has been
challenging due to the required high quality of data, high computation load, and high-power consumption.
The aim of this paper is to diagnose the heart condition based on Phonocardiogram analysis using
Machine Learning techniques assuming limited processing power to be encapsulated later in a mobile
device. The cardiovascular system is modelled in a transfer function to provide PCG signal recording as it
would be recorded at the wrist. The signal is, then, decomposed using filter bank and the analysed using
discriminant function. The results showed that PCG with a 19 dB Signal-to-Noise-Ratio can lead to 97.33%
successful diagnosis.
Phonocardiogram Based Diagnosis Using Machine Learning : Parametric Estimatio...bioejjournal
The heart sound signal, Phonocardiogram (PCG) is difficult to interpret even for experienced cardiologists. Interpretation are very subjective depending on the hearing ability of the physician. mHealth has been the adopted approach towards quick diagnosis using mobile devices. However, it has been challenging due to the required high quality of data, high computation load, and high-power consumption. The aim of this paper is to diagnose the heart condition based on Phonocardiogram analysis using Machine Learning techniques assuming limited processing power to be encapsulated later in a mobile device. The cardiovascular system is modelled in a transfer function to provide PCG signal recording as it would be recorded at the wrist. The signal is, then, decomposed using filter bank and the analysed using discriminant function. The results showed that PCG with a 19 dB Signal-to-Noise-Ratio can lead to 97.33% successful diagnosis.
Respiration Sensor
The respiration sensor is a sensitive girth sensor worn using an easy fitting high durability woven elastic band fixed with a length-adjustable webbing belt. It detects chest or abdominal expansion/contraction and outputs the respiration waveform.
Geometric distortion of functional MR images especially of DWI hinders the visualization of the frontal & temporal regions. This is a simple & reliable approach to get rid of. This needs no special software or hardware & applies to old systems.
Table of Contents - June 2021, Volume 12, Number 3sipij
Signal & Image Processing : An International Journal is an Open Access peer-reviewed journal intended for researchers from academia and industry, who are active in the multidisciplinary field of signal & image processing. The scope of the journal covers all theoretical and practical aspects of the Digital Signal Processing & Image processing, from basic research to development of application.
Authors are solicited to contribute to the journal by submitting articles that illustrate research results, projects, surveying works and industrial experiences that describe significant advances in the areas of Signal & Image processing.
PHONOCARDIOGRAM-BASED DIAGNOSIS USING MACHINE LEARNING: PARAMETRIC ESTIMATION...bioejjournal
The heart sound signal, Phonocardiogram (PCG) is difficult to interpret even for experienced
cardiologists. Interpretation are very subjective depending on the hearing ability of the physician. mHealth
has been the adopted approach towards quick diagnosis using mobile devices. However, it has been
challenging due to the required high quality of data, high computation load, and high-power consumption.
The aim of this paper is to diagnose the heart condition based on Phonocardiogram analysis using
Machine Learning techniques assuming limited processing power to be encapsulated later in a mobile
device. The cardiovascular system is modelled in a transfer function to provide PCG signal recording as it
would be recorded at the wrist. The signal is, then, decomposed using filter bank and the analysed using
discriminant function. The results showed that PCG with a 19 dB Signal-to-Noise-Ratio can lead to 97.33%
successful diagnosis.
Phonocardiogram Based Diagnosis Using Machine Learning : Parametric Estimatio...bioejjournal
The heart sound signal, Phonocardiogram (PCG) is difficult to interpret even for experienced cardiologists. Interpretation are very subjective depending on the hearing ability of the physician. mHealth has been the adopted approach towards quick diagnosis using mobile devices. However, it has been challenging due to the required high quality of data, high computation load, and high-power consumption. The aim of this paper is to diagnose the heart condition based on Phonocardiogram analysis using Machine Learning techniques assuming limited processing power to be encapsulated later in a mobile device. The cardiovascular system is modelled in a transfer function to provide PCG signal recording as it would be recorded at the wrist. The signal is, then, decomposed using filter bank and the analysed using discriminant function. The results showed that PCG with a 19 dB Signal-to-Noise-Ratio can lead to 97.33% successful diagnosis.
Respiration Sensor
The respiration sensor is a sensitive girth sensor worn using an easy fitting high durability woven elastic band fixed with a length-adjustable webbing belt. It detects chest or abdominal expansion/contraction and outputs the respiration waveform.
Geometric distortion of functional MR images especially of DWI hinders the visualization of the frontal & temporal regions. This is a simple & reliable approach to get rid of. This needs no special software or hardware & applies to old systems.
Table of Contents - June 2021, Volume 12, Number 3sipij
Signal & Image Processing : An International Journal is an Open Access peer-reviewed journal intended for researchers from academia and industry, who are active in the multidisciplinary field of signal & image processing. The scope of the journal covers all theoretical and practical aspects of the Digital Signal Processing & Image processing, from basic research to development of application.
Authors are solicited to contribute to the journal by submitting articles that illustrate research results, projects, surveying works and industrial experiences that describe significant advances in the areas of Signal & Image processing.
Design and development of electro optical system for acquisition of ppg signa...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Wireless Body Area Networks for Healthcare: A Surveyijasuc
Wireless body area networks (WBANs) are emerging as important networks, applicable in various
fields. This paper surveys the WBANs that are designed for applications in healthcare. We present a
comprehensive survey consisting of stand-alone sections focusing on important aspects of WBANs. We
examine the following: monitoring and sensing, power efficient protocols, system architectures, routing
and security. We conclude by discussing some open research issues, their potential solutions and future
trends.
Extraction of respiratory rate from ppg signals using pca and emdeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Extraction of respiratory rate from ppg signals using pca and emdeSAT Journals
Abstract Photoplethysmography is a non-invasive electro-optic method developed by Hertzman, which provides information on the blood volume flowing at a particular test site on the body close to the skin. PPG waveform contains two components; one, attributable to the pulsatile component in the vessels, i.e. the arterial pulse, which is caused by the heartbeat, and gives a rapidly alternating signal (AC component). The second one is due to the blood volume and its change in the skin which gives a steady signal that changes very slowly (DC component). PPG signal consists of not only the heart-beat information but also a respiratory signal. Estimation of respiration rates from Photoplethysmographic (PPG) signals would be an alternative approach for obtaining respiration related information.. There have been several efforts on PPG Derived Respiration (PDR), these methods are based on different signal processing techniques like filtering, wavelets and other statistical methods, which work by extraction of respiratory trend embedded into various physiological signals. PCA identifies patterns in data, and expresses the data in such a way as to highlight their similarities and differences. Since patterns in data can be hard to find in data of high dimension, where the luxury of graphical representation is not available, PCA is a powerful tool for analyzing such data. Due to external stimuli, biomedical signals are in general non-linear and non-stationary. Empirical Mode Decomposition is ideally suited to extract essential components which are characteristic of the underlying biological or physiological processes. The basis functions, called Intrinsic Mode Functions (IMFs) represent a complete set of locally orthogonal basis functions whose amplitude and frequency may vary over time. The contribution reviews the technique of EMD and related algorithms and discusses illustrative applications. Test results on PPG signals of the well known MIMIC database from Physiobank archive reveal that the proposed EMD method has efficiently extracted respiratory information from PPG signals. The evaluated similarity parameters in both time and frequency domains for original and estimated respiratory rates have shown the superiority of the method. Index Terms: Respiratory signal, PPG signal, Principal Component Analysis, EMD, ECG
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Body Temperature & Blood Pressure Remote MonitoringIJMTST Journal
In this paper we present an electronic system to perform a non-invasive measurement of the blood pressure based on the oscillometric method, which does not suffer from the limitations of the well-known auscultatory one. With reference to other similar devices, a great improvement of our measurement system is achieved since it performs the transmission of the systolic and diastolic pressure values to a remote computer. This aspect is very important when the simultaneous monitoring of multi-patients is required. Blood pressure readings with help of developed algorithm has been calculated and transmitted via Bluetooth kit to the stationary computer. Numerical reading values of systolic and diastolic blood pressure remotely recorded and displayed with help of LCD as well stationary computer.
Improving the Design of Blood Pressure and Blood Saturation MonitorsLuca Parisi
A blood pressure monitor or sphygmomanometer can
be either manual or automatic, employing respectively either the
auscultatory method or the oscillometric method.
The manual version of the sphygmomanometer involves an
inflatable cuff with a stethoscope adopted to detect the sounds
generated by the arterial walls to measure blood pressure in an artery.
An automatic sphygmomanometer can be effectively used to
monitor blood pressure through a pressure sensor, which detects
vibrations provoked by oscillations of the arterial walls.
The pressure sensor implemented in this device improves the
accuracy of the measurements taken.
Design of the Pulse Oximetry Measurement Circuit and Its Sensing System Based...IOSRJEEE
The pulse oximetry circuit and its sensing system is designed based on the standard CMOS technology of 0.18um. The reflection oxygen sensor is used to collect the pulse oximeter signal of human body, then the collected physiological signals are processed by the data processing circuit The data processing circuit is composed of two parts: the amplifying circuit and the band-pass filter circuit, and the pulse oximeter data processed by the data processing circuit is written into the tag through the SPI communication The RFID reader read the data in the RFID tag through wireless communication, and display the data . The experimental results show that the maximum error is ±1%. The maximum error of the pulse is ±1.9%. The stability and feasibility of pulse blood oxygen sensing system is demonstrated in this paper and it will have a good application prospect in the direction of wearable medical wisdom research
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Research Inventy : International Journal of Engineering and Scienceinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Blood Flow Sensors and Meters with their workingjafarfarwa
These are slides about blood flow meters and sensors with introduction to a new technology of flexible sensors that can be used as a lie detector ... slides have prepared by me with a great hardwork on material,animations and transitions.
BLOOD IS A CONTINOUSLY VARYING QUANTITY and hard to measure .it can be magnetized to create polarity so that we measure the blood flow . blood can also be sensed using ultrasonic beams.
and the precious and amazing technology is FLEXIBLE SENSORS that can sense blood and measure its velocity . they can sense even a very very small change in the temprature of blood upto 3 decimal places . So see it in my slides and enjoy . hope u will satisfied by it .
THANKYOU :)
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
2. ABSTRACT
Photoplethysmography (PPG) technology has been used to develop
small, wearable, pulse rate sensors. These devices, consisting of infrared light-emitting
diodes (LEDs) and photodetectors, offer a simple, reliable, low-cost means of
monitoring the pulse rate noninvasively. Recent advances in optical technology have
facilitated the use of high-intensity green LEDs for PPG, increasing the adoption of this
measurement technique. In this review, we briefly present the history of PPG and recent
developments in wearable pulse rate sensors with green LEDs. The application of
wearable pulse rate monitors is discussed.
The principle behind PPG sensors is optical detection of blood volume
changes in the microvascular bed of the tissue. The sensor system consists of a light
source and a detector, with red and infrared (IR) light-emitting diodes (LEDs)
commonly used as the light source. The PPG sensor monitors changes in the light
intensity via reflection from or transmission through the tissue. The changes in light
intensity are associated with small variations in blood perfusion of the tissue and
provide information on the cardiovascular system, in particular, the pulse rate.
i
5. LIST OF FIGURES
FIGURE NO. TITLE PAGE NO:
3.1 TRANSMISSION MODE PPG 10
3.2 REFLECTIVE MODE PPG 11
3.3 PPG WAVEFORM 12
3.4 EAR PIECE PPG SENSOR 13
3.5 PPG RING SENSOR 15
3.6 WRIST WATCH TYPE SENSOR 16
3.7 FOREHEAD SENSORS 16
iv
6. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
CHAPTER 1
INTRODUCTION
It is important to monitor the perfusion of the circulation. The most
important cardiopulmonary parameter is blood pressure, but monitoring it is
complicated. A second important parameter is blood flow, which is related to blood
pressure. We can monitor the blood perfusion in large vessels using ultrasound devices,
but it is not practical to use these routinely. Several devices for monitoring blood
perfusion have been developed but unfortunately, it is difficult to find a practical device.
However, the perfusion of blood flow and blood pressure can be determined easily
using a pulse rate monitor.
Wearable pulse rate sensors based on Photoplethysmography (PPG)
have become increasingly popular, with more than ten companies producing these
sensors commercially. The principle behind PPG sensors is optical detection of blood
volume changes in the microvascular bed of the tissue. The sensor system consists of a
light source and a detector, with red and infrared (IR) light-emitting diodes (LEDs)
commonly used as the light source. The PPG sensor monitors changes in the light
intensity via reflection from or transmission through the tissue. The changes in light
intensity are associated with small variations in blood perfusion of the tissue and
provide information on the cardiovascular system, in particular, the pulse rate. Due to
the simplicity of this device, wearable PPG pulse rate sensors have been developed.
This review describes the basic principles of PPG, previous and current developments
in wearable pulse rate monitors with a light source, and the elimination of motion
artifacts.
Arterial blood pressure (ABP) is one of the most important
hemodynamic characteristics of the cardiovascular system. It not only changes with the
heart pulsation, but also varies naturally throughout the day as part of the circadian
rhythm. In addition, ABP also changes in response to stress, drugs or diseases. Thus,
Dept. of ECE, LMCST 1
7. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
the development of an accurate and reliable method for continuous ABP measurement
has attracted much research effort. Although both invasive and non-invasive methods
have been developed, the latter are more desirable for replacing the invasive method
that is currently used in clinical practice.
Photoplethysmography (PPG) technology has been used to develop
small, wearable, pulse rate sensors. These devices, consisting of infrared light-emitting
diodes (LEDs) and photodetectors, offer a simple, reliable, low-cost means of
monitoring the pulse rate noninvasively. Recent advances in optical technology have
facilitated the use of high-intensity green LEDs for PPG, increasing the adoption of this
measurement technique. In this review, we briefly present the history of PPG and recent
developments in wearable pulse rate sensors with green LEDs. The application of
wearable pulse rate monitors is discussed.
Dept. of ECE, LMCST 2
8. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
CHAPTER 2
PLETHYSMOGRAPHY
2.1 DEFINITION
Plethysmography is a non-invasive diagnostic treatment used for
screening and patient follow-ups with various arterial and venous pathologies. This
treatment is concerned with the measurement of volume and volume displacement of
blood. The screening provides a circulatory assessment via a waveform representation
of pulsatile peripheral blood flow. Instrumentation providing blood volume parameters
exists but nothing to measure volume directly. An example of this instrumentation is
the use of an ultrasound.
While ultrasound provides hemodynamic (hemodynamic refers to the
forces generated by the heart and the motion of blood through the cardiovascular
system) data on vein segments, plethysmography provides information that is indirectly
related to venous volume changes. The data obtained is not specific to venous function
because limb volume changes may be caused by several factors.
Rapid changes are typically associated with changes in blood volume or
movement artifact. If movement is controlled, information specific to blood volume can
be obtained. Further separation of arterial and venous flow effects can be observed
through electronic filtration.
Venous flow changes typically involve long transient time constants
with duration of seconds or minutes. Venous displacement measurements are typically
associated with shifts in body position and limb compressions which allow
measurements of magnitude and duration.
Dept. of ECE, LMCST 3
9. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
2.2 TYPES OF PLETHYSMOGRAPHY
The different types of plethysmography is classified according to the
basis of the source used. Four main types of plethysmography exist. All of them are
used in clinical applications inorder to monitor the patients at different parts of the
body. They are:
1. Air-Displacement
2. Photo
3. Strain gauge
4. Impedance
2.2.1 Air-Displacement plethysmography
It is mainly done for the whole body. With air-displacement
plethysmography, the volume of an object is measured indirectly by determining the
volume of air it displaces inside an enclosed chamber (plethysmograph). Thus, human
body volume is measured when a subject sits inside the chamber and displaces a volume
of air equal to his or her body volume. Body volume is calculated indirectly by
subtracting the volume of air remaining inside the chamber when the subject is inside
from the volume of air in the chamber when it is empty. The volume of air inside the
chamber is calculated by slightly changing the size of the chamber (e.g. by moving a
diaphragm in one of the walls) and applying relevant physical gas laws to determine
the total volume from the changing air pressure within the chamber as its size is
altered. By subtracting the remaining volume of air inside the chamber when the patient
is inside from the volume of air in the chamber empty, you get the body volume.
Dept. of ECE, LMCST 4
10. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
2.2.2 Photo plethysmography
They are mainly used for monitoring blood perfusion in different parts
of the body. It is the simplest way of monitoring the blood perfusion non-invasively.
Photoelectric plethysmography is concerned with assessment based on cutaneous blood
volume. An electrode consisting of an infrared LED and a photosensor is attached to
the skin. Light transmitted into the skin is scattered and absorbed by tissue in the
illuminated field. Blood attenuates the reflected light and intensity of reflected light
changes with blood tissue density. The voltage signal generated by the photosensor is
amplified by a DC circuit. Low frequencies are passed which produces relatively stable
tracing. This corresponds to blood density in the underlying tissue.
2.2.3 Strain gauge plethysmography
Strain gauge plethysmography uses a transducer filled with mercury or
indium- gallium metal alloy conductor. Stretching the strain gauge causes a decrease is
diameter causing an increase in voltage. When wrapped around a limb segment, the
gauge provides a circumferential measurement that can be used to compute area. The
“slice volume” of the limb segment changes as the limb volume expands and contracts.
The mercury gauge is a very sensitive indicator of changes in the digital volume and
permits measurement of systolic blood pressure at any level of the extremity.
2.2.4 Impedance plethysmography
The final type of plethysmography is impedance plethysmography. A
weak current is passed through a limb and the electrical resistance to current flow is
measured. Four conductive bands are taped around the limb as outer and inner pairs of
electrodes. The inner pair is then used to measure electrical resistance.
Dept. of ECE, LMCST 5
11. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
CHAPTER 3
PHOTOPLETHYSMOGRAPHY
3.1 PRINCIPLE
The principle of PPG has been reviewed previously, and is explained
briefly here. Light travelling though biological tissue can be absorbed by different
substances, including pigments in the skin, bone, and arterial and venous blood. Most
changes in blood flow occur mainly in the arteries and arterioles (but not in the veins).
For example, arteries contain more blood volume during the systolic phase of the
cardiac cycle than during the diastolic phase. PPG sensors optically detect changes in
the blood flow volume (i.e., changes in the detected light intensity) in the microvascular
bed of tissue via reflection from or transmission through the tissue.
3.2 LIGHT WAVELENGTH
The interaction of light with biological tissue is complex and includes
the optical processes of (multiple) scattering, absorption, reflection, transmission and
fluorescence (Anderson and Parrish 1981). Several researchers have investigated the
optical processes in relation to PPG measurements. Researchers have highlighted the
key factors that can affect the amount of light received by the photodetector; the blood
volume, blood vessel wall movement and the orientation of red blood cells (RBC). The
orientation effect has been demonstrated by recording pulsatile waveforms from dental
pulp and in a glass tube where volumetric changes should not be possible, and more
recently by N¨aslund et al (2006) who detected pulsatile waveforms in bone. The
recorded pulses do bear a direct relationship with perfusion, and the greater the blood
volume the more the light source is attenuated. However, attempts at pulse amplitude
quantification (‘calibration’) have been largely unsuccessful.
Dept. of ECE, LMCST 6
12. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
The interaction of light with biological tissue can be quite complex and
may involve scattering, absorption and/or reflection. Anderson and Parrish examined
the optical characteristics and penetration depth of light in human skin. The wavelength
of optical radiation is also important in light–tissue interactions (Cui et al 1990), and
for three main reasons:
1. The optical water window
2. Isobestic wavelength
3. Tissue penetration depth
3.2.1. The optical water window
The main constituent of tissue is water that absorbs light very strongly
in the ultraviolet and the longer infrared wavelengths. The shorter wavelengths of light
are also strongly absorbed by melanin. There is, however, a window in the absorption
spectra of water that allows visible (red) and near infrared light to pass more easily,
thereby facilitating the measurement of blood flow or volume at these wavelengths.
Thus, the red or near infrared wavelengths are often chosen for the PPG light source
(Jones 1987).
3.2.2. Isobestic wavelength
Significant differences exist in absorption between oxyhaemoglobin
(HbO2) and reduced hemoglobin (HB) except at the isobestic wavelengths (Gordy and
Drabkin 1957). For measurements performed at an isobestic wavelength (i.e. close to
805 nm, for near infrared range) the signal should be largely unaffected by changes in
blood oxygen saturation.
Dept. of ECE, LMCST 7
13. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
3.2.3. Tissue penetration depth
The depth to which light penetrates the tissue for a given intensity of
optical radiation depends on the operating wavelength (Murray and Marjanovic 1997).
In PPG the catchment (study) volume, depending on the probe design, can be of the
order of 1 cm3 for transmission mode systems. PPG can provide information about
capillary nutritional blood flow and the thermoregulatory blood flow through arterio-venous
anastomosis shunt vessels.
Within the visible region, the dominant absorption peak corresponded
to the blue region of the spectrum, followed by the green-yellow region (between 500
and 600 nm) corresponding to red blood cells. The shorter wavelengths of light are
strongly absorbed by melanin. Water absorbs light in the ultraviolet and longer IR
regime; however, red and near-IR light pass easily. As a result, IR wavelengths have
been used as a light source in PPG sensors.
Blood absorbs more light than the surrounding tissue. Therefore, a
reduction in the amount of blood is detected as an increase in the intensity of the
detected light. The wavelength and distance between the light source and photodetector
(PD) determine the penetration depth of the light.
Green light is suitable for the measurement of superficial blood flow in
skin. Light with wavelengths between 500 and 600 nm (the green-yellow region of the
visible spectrum) exhibits the largest modulation depth with pulsatile blood absorption.
IR or near-IR wavelengths are better for measurement of deep-tissue blood flow (e.g.,
blood flow in muscles). Thus, IR light has been used in PPG devices for some time.
However, green-wavelength PPG devices are becoming increasingly popular due to the
large intensity variations in modulation observed during the cardiac cycle for these
wavelengths. A green LED has much greater absorptivity for both oxyhaemoglobin and
deoxyhaemoglobin compared to infrared light.
Dept. of ECE, LMCST 8
14. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
Therefore, the change in reflected green light is greater than that in
reflected infrared light when blood pulses through the skin, resulting in a better signal-to-
noise ratio for the green light source. Several green-light-based
photoplethysmographs are available commercially. For example, MIO Global has
developed the MIO Alpha in cooperation with Philips; this measures the
electrocardiogram (ECG) with 99% accuracy, even while cycling at speeds of up to 24
kmph. For daily use, Omron has developed a green light pulse rate monitor (HR-500U,
OMRON, Muko, Japan).
Furthermore, the use of video cameras using the signal based on the red
green blue (RGB) colour space has been considered, as shown in Section 3.3. The green
signal was found to provide the strongest plethysmographic signal among camera RGB
signals. Haemoglobin absorbs green light better than red and green light penetrates
tissue to a deeper level than blue light. Therefore, the green signal contains the strongest
plethysmographic signal.
3.3 DIFFERENT MODES OF PPG
The different modes in PPG is categorized according to the positions in
placement of the light source and the photodetector. According to this way there are
two modes of operation of PPG. They are:
1. Transmission
2. Reflectance
3.3.1 Transmission Mode
In transmission mode, the light transmitted through the medium is
detected by a PD opposite the LED source. The transmission mode is capable of
obtaining a relatively good signal, but the measurement site may be limited. To be
Dept. of ECE, LMCST 9
15. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
effective, the sensor must be located on the body at a site where transmitted light can
be readily detected, such as the fingertip, nasal septum, cheek, tongue, or earlobe.
Sensor placement on the nasal septum, cheek or tongue is only effective under
anesthesia.
In transmission mode, when the IR LED illuminates, the light is forced
to fall on the part of the body on to which the device is kept. The light start transmitting
through the body part. In this case some of the light is absorbed by the capillary bed,
some will be reflected back from the capillary bed, some transmits through and reach
the photodiode kept at the opposite end of the source and the rest reflect back at the
surface itself. The light transmitted through the body part and reaching the photodiode
is noted and the waveform is noted as the plethysmographic waveform.
Fig 3.1 Transmission mode PPG
The fingertip and earlobe are the preferred monitoring positions;
however, these sites have limited blood perfusion. In addition, the fingertip and earlobe
are more susceptible to environmental extremes, such as low ambient temperatures
(e.g., for military personnel or athletes in training). The greatest disadvantage is that the
fingertip sensor interferes with daily activates.
Dept. of ECE, LMCST 10
16. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
3.3.2 Reflectance Mode
Reflectance mode eliminates the problems associated with sensor
placement, and a variety of measurement sites can be used (as discussed in the
following section). However, reflection-mode PPG is affected by motion artifacts
and pressure disturbances. Any movement, such as physical activity, may lead to
motion artifacts that corrupt the PPG signal and limit the measurement accuracy
of physiological parameters. Pressure disturbances acting on the probe, such as the
contact force between the PPG sensor and measurement site, can deform the arterial
geometry by compression. Thus, in the reflected PPG signal, the AC amplitude may
be influenced by the pressure exerted on the skin.
Fig 3.2 Reflectance mode PPG
In this case also as the light is illuminated, some light will be transmitted
through, some will be reflected back at the surface itself, some are absorbed by the
capillary bed. Here the reflected signals are captured by the photodiode kept adjacent
the source and the waveform is noted according to the amount of light falling on the
photodiode after reflection.
Dept. of ECE, LMCST 11
17. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
3.4 PLETHYSMOGRAPHIC WAVEFORM
PPG sensors optically detect changes in the blood flow volume (i.e.,
changes in the detected light intensity) in the microvascular bed of tissue via reflection
from or transmission through the tissue. Photoplethysmographic waveform, consisting
of direct current (DC) and alternating current (AC) components. The DC component
of the PPG waveform corresponds to the detected transmitted or reflected optical
signal from the tissue, venous blood, non-pulsatile component of artery blood and
depends on the structure of the tissue and the average blood volume of both arterial
and venous blood. Note that the DC component changes slowly with respiration.
Fig 3.3 PPG waveform
The AC component shows changes in the blood volume that occurs
between the systolic and diastolic phases of the cardiac cycle. The fundamental
frequency of the AC component depends on the heart rate and is superimposed onto
the DC component. The AC current shows the pulsatile component of the artery blood.
The variation of blood flow represented by AC component is the flow during the
systolic phase of the cardiac cycle.
Dept. of ECE, LMCST 12
18. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
3.5 PHOTOPLETHYSMOGRAPHIC DEVICES
Wearable pulse rate sensors based on photoplethysmography (PPG)
have become increasingly popular in recent years with the technology advancing day
by day. Nowadays more than ten companies producing these sensors commercially.
The principle of PPG have become more popular as it is non-invasive. Due to the
simplicity of this device, wearable PPG pulse rate sensors have been developed. Some
of the mostly used devices are:
3.5.1 Earphone earbud PPG sensors
Fig 3.4 Earpiece PPG sensor
Dept. of ECE, LMCST 13
19. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
Earphone/earbud PPG sensors are also available and provide greater
comfort for the user. In this design, a reflective photosensor is embedded into each
earbud, as shown in Figure 3. The sensor earbuds are inserted into the ear and
positioned against the inner side of the tragus to detect the amount of light reflected
from the subcutaneous blood vessels in the region. The PPG sensor earbuds look and
work like a regular pair of earphones, requiring no special training for use.
A headset with an ear-clip, transmission-type PPG sensor allows
continuous, real-time monitoring of heart rate while listening to music during daily
activities. In addition, the proposed headset is equipped with a triaxial accelerometer,
which enables the measurement of calorie consumption and step-counting. However,
over the course of a variety of daily activities (e.g., walking, jogging, and sleeping),
the PPG sensor signal may become contaminated with motion artifacts.
3.5.2 PPG ring sensor
The most common commercially available PPG sensor is based on
finger measurement sites. The transmission mode PPG sensors are commonly used for
this operation. Finger sites are easily accessed and provide good signal for PPG sensor
probes. For example, a ring sensor can be attached to the base of the finger for
monitoring beat-to-beat pulsations. Data from the ring sensor are sent to a computer
via a radiofrequency transmitter, as shown in Figure.
To minimize motion artifacts, a double ring design was developed to
reduce the influence of external forces, acceleration and ambient light, and to hold the
sensor gently and securely to the skin, so that the blood circulation in the finger
remained unobstructed. Experiments have verified the resistance of the ring sensor to
interfering forces and acceleration acting on the ring body. Benchmark testing with
FDA-approved PPG and ECG sensors revealed that the ring sensor is comparable in
the detection of beat-to-beat pulsations, despite disturbances.
Dept. of ECE, LMCST 14
20. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
Fig 3.5 PPG ring sensor
3.5.3 Wristwatch-type sensors
Wristwatch-type sensors have been developed and commercialized by
several companies. These devices, although much easier to wear, are not usually used
in clinical settings, due to several technical issues. However, a novel PPG array sensor
module with a wristwatch-type design has been developed. The proposed module
measures the PPG signal from the radial artery and the ulnar artery of the wrist, whereas
previous methods obtained signals from the capillaries in the skin. Phototransistors and
IR-emitting diodes were placed in an array format to improve the PPG signal sensitivity
and level of accuracy.
Various arrays were considered for optimization. A conductive fiber
wristband was used to reduce external noise. In the experiments, the proposed module
was assessed and compared with the commercially available product produced by
BIOPAC. A reflective brachial PPG sensor has also been examined. Although the pulse
amplitude is lower than those from the finger and earlobe, the PPG pulse waveforms
from regions in the vicinity of a human artery could be detected and measured easily.
Dept. of ECE, LMCST 15
22. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
Forehead sensors have shown greater sensitivity to pulsatile signal
changes under low perfusion conditions, compared with other peripheral body
locations [31]. The thin-skin layer of the forehead, coupled with a prominent bone
structure, helps to direct light back to the PD. Sensor placement on the forehead has
been shown to result in decreased motion artifacts during certain types of physical
activity.
3.6 ADVANTAGES
PPG sensors has provided many advantages over conventional
techniques. Some of the major advantages of this technology is:
1. PPG is inexpensive and cheap.
2. Since it consumes very less power, it is an ideal ambulatory device.
3. Does not need special training or guidance.
4. A range of clinically relevant parameters can be obtained from PPG signal.
5. They offer a simple, reliable, low-cost means of monitoring pulse rate non-invasively.
Dept. of ECE, LMCST 17
23. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
CHAPTER 4
CONCLUSION
Wearable PPG sensors have become very popular. Although a great
deal of progress has been made in the hardware and signal processing, an
acceptable wearable PPG sensor device has yet to be developed. Green light
sources in PPG sensors minimize motion artifacts. Several filters and algorithms have
been examined to mimic daily activities on limited time scales. However, better
accuracy and reproducibility of real environments are required to eliminate
motion artifacts. Further research is needed for the development of practical
wearable PPG pulse rate monitors and pulse oximeters.
The calculation of blood pressure and pulse rate become very common
in clinical applications inorder to check the patients’ condition. Several devices for
monitoring blood perfusion have been developed but unfortunately, it is difficult to
find a practical device. However, the perfusion of blood flow and blood pressure can
be determined easily using a pulse rate monitor. PPG technology has provided an
easy method in analyzing the technical measurement within the blood and blood
volume changes associated with it. They are especially used to develop small
wearable pulse rate sensors which can be easily used by patients itself. No further
knowledge of using the device is required in using these devices. They can be used
without much knowledge.
Wireless wearable sensors have become more familiar with the new
incoming technologies where the doctor doesn’t need much guidance. The
technology has become popular much due to its non-invasive nature.
Dept. of ECE, LMCST 18
24. WEARABLE PHOTOPLETHYSMOGRAPHIC SENSORS
REFERENCE
1. Togawa, T.; Tamura, T.; Öberg, P.Å. Biomedical Sensors and Instruments,
2nd ed.; CRC Press: New York, NY, USA, 2011; pp. 19–190.
2. Challoner, A.V.J . Photoelectric plethysmography for estimating cutaneous
blood flow. In Non-invasive Physiological Measurement; Rolfe, P., Ed.;
Academic Press: Oxford, UK, 1979; Volume 1, pp. 127–151.
3. Kamal, A.A.R.; Harness, J.B.; Irving, G.; Mearns, A.J. Skin
photoplethysmography—A review.
Comput. Methods Programs Biomed. 1989, 28, 257–269.
4. Alen.J . Ph o t o p l e t h y smo g r a p h y and i t s a p p l i c a t i o n i n c l i n i c a l
p h y s i o l o g i c a l me a s u r eme n t .
Physiol. Meas. 2007, 28, R1–R39.
5. Anderson, R.R.; Parris, E.D. The optics of human skin. J. Invest. Dermatol. 1981,
77, 13–19.
6. Giltvedt, J.; Sita, A.; Helme, P. Pulsed multifrequency photoplethysmograph.
Med. Biol. Eng. Comput. 1984, 22, 212–215.
7. Cui, W.; Ostrander, L.E.; Lee, B.Y. In vivo reflectance of blood and tissue as
a function of light wavelength. IEEE Trans. Biomed. Eng. 1990, 37, 632–639.
8. Z i j l s t r a , W.G. ; Bu u r sma , A. ; Me e u w s e n - v a n d e r R o e s t ,
W. P . A b s o r p t i o n s p e c t r a o f h uma n f e t a l a n d a d u l t
o x y h emo g l o b i n , d e - o x y h emo g l o b i n , c a r b o x y h emo g l o b i n ,
a n d Me t h emo g l o b i n . Cl i n . C h em . 1 9 9 1 , 3 7 , 1 6 3 3 – 1 6 3 8 .
9. Meada, Y.; Sekine, M.; Tamura, T. The advantage of green reflected
J. Med. Syst. 2011, 35, 829–834.
Dept. of ECE, LMCST 19