This document summarizes the key aspects of non-contact heart rate measurement using video images and blind source separation. It begins by introducing the need for non-invasive cardiovascular monitoring and photoplethysmography (PPG) as a method. An experimental setup using a webcam to record facial videos alongside a finger pulse sensor is described. The document then explains how blind source separation can be applied to the video images to extract heart rate measurements, tolerate motion artifacts, and measure heart rate from multiple persons simultaneously in a non-contact manner.
The document describes Ming-Zher Poh's invention of the Medical Mirror, which allows contactless measurement of heart rate using a webcam and mirror setup. The mirror contains a webcam and LCD monitor behind a two-way mirror. Software analyzes subtle light reflections caused by blood flow to determine heart rate in real-time. This provides a more comfortable alternative to external sensors. Future applications could non-invasively monitor multiple health parameters using the system.
The document describes a medical mirror that can track and display a user's heart rate in real time using only a webcam, without any external sensors. The mirror consists of an LCD monitor with a built-in webcam connected to analysis software running on a laptop. It uses computer vision techniques to detect the user's face, extract color signals, and analyze the frequency corresponding to heart rate. The technology provides a low-cost, convenient way to monitor heart rate and could help detect potential health issues.
The document describes the Medical Mirror, an invention by Ming-Zher Poh at MIT in 2009. The Medical Mirror uses a webcam and two-way mirror installed in a frame to non-invasively measure a person's heart rate when they look at their reflection. It works by detecting subtle light absorption changes caused by blood flow with each heartbeat. The mirror provides real-time heart rate readings and has advantages over traditional sensors by being contact-free and fitting seamlessly into the home environment to conveniently track health. Future work aims to expand its physiological monitoring capabilities.
The document describes a new type of "medical mirror" interface that can measure a user's heart rate without external sensors. It works by using a webcam and software to analyze subtle light intensity changes in a user's face as their blood pulses, visible through ambient light. When a user looks at their reflection in the mirror, a box appears around their face and their continuously updating heart rate is displayed. This novel interface aims to conveniently allow users to track their daily health with minimal effort by blending physiological monitoring into everyday mirror use.
This presentation includes what is accident detection system ppt ,what are its requirements and how its works and its advantages,disadvantages and applications,Results and future sccope and at last conclusion
The document discusses the Blue Brain project which aims to simulate the human brain on a supercomputer. It seeks to reverse engineer the brain into a digital model using artificial neural networks. This could help understand brain functions like thinking and memory. The Blue Brain project in Lausanne uses supercomputers with thousands of CPUs and memory to simulate brain circuits. Uploading a human brain may be possible using nanobots to monitor brain activity and interface it with a computer. While this could expand human intelligence, it also risks negative impacts like viruses attacking computerized brains or humans becoming too dependent on technology.
The document describes a capsule camera, also known as capsule endoscopy. It provides a brief history of endoscopy and describes how the capsule camera was invented in 2000. The summary provides an overview of the key components of the capsule camera, including a CMOS image sensor, batteries, transmitter, and antenna. It also describes how the capsule camera works, taking images as it passes through the digestive tract that are transmitted to an external recorder. The summary concludes by mentioning some of the advantages of capsule cameras, such as being painless and providing accurate images of the small intestine.
The document describes Ming-Zher Poh's invention of the Medical Mirror, which allows contactless measurement of heart rate using a webcam and mirror setup. The mirror contains a webcam and LCD monitor behind a two-way mirror. Software analyzes subtle light reflections caused by blood flow to determine heart rate in real-time. This provides a more comfortable alternative to external sensors. Future applications could non-invasively monitor multiple health parameters using the system.
The document describes a medical mirror that can track and display a user's heart rate in real time using only a webcam, without any external sensors. The mirror consists of an LCD monitor with a built-in webcam connected to analysis software running on a laptop. It uses computer vision techniques to detect the user's face, extract color signals, and analyze the frequency corresponding to heart rate. The technology provides a low-cost, convenient way to monitor heart rate and could help detect potential health issues.
The document describes the Medical Mirror, an invention by Ming-Zher Poh at MIT in 2009. The Medical Mirror uses a webcam and two-way mirror installed in a frame to non-invasively measure a person's heart rate when they look at their reflection. It works by detecting subtle light absorption changes caused by blood flow with each heartbeat. The mirror provides real-time heart rate readings and has advantages over traditional sensors by being contact-free and fitting seamlessly into the home environment to conveniently track health. Future work aims to expand its physiological monitoring capabilities.
The document describes a new type of "medical mirror" interface that can measure a user's heart rate without external sensors. It works by using a webcam and software to analyze subtle light intensity changes in a user's face as their blood pulses, visible through ambient light. When a user looks at their reflection in the mirror, a box appears around their face and their continuously updating heart rate is displayed. This novel interface aims to conveniently allow users to track their daily health with minimal effort by blending physiological monitoring into everyday mirror use.
This presentation includes what is accident detection system ppt ,what are its requirements and how its works and its advantages,disadvantages and applications,Results and future sccope and at last conclusion
The document discusses the Blue Brain project which aims to simulate the human brain on a supercomputer. It seeks to reverse engineer the brain into a digital model using artificial neural networks. This could help understand brain functions like thinking and memory. The Blue Brain project in Lausanne uses supercomputers with thousands of CPUs and memory to simulate brain circuits. Uploading a human brain may be possible using nanobots to monitor brain activity and interface it with a computer. While this could expand human intelligence, it also risks negative impacts like viruses attacking computerized brains or humans becoming too dependent on technology.
The document describes a capsule camera, also known as capsule endoscopy. It provides a brief history of endoscopy and describes how the capsule camera was invented in 2000. The summary provides an overview of the key components of the capsule camera, including a CMOS image sensor, batteries, transmitter, and antenna. It also describes how the capsule camera works, taking images as it passes through the digestive tract that are transmitted to an external recorder. The summary concludes by mentioning some of the advantages of capsule cameras, such as being painless and providing accurate images of the small intestine.
Wearable technology refers to electronic devices that can be incorporated into items of clothing and accessories. Some examples include smart watches, fitness trackers, and Google Glass. Wearable devices perform similar tasks as mobile phones and computers by allowing hands-free use and constant access to features like notifications, activity tracking, and communication. While wearable technology provides benefits such as portability and mobility, challenges remain around potential health issues, cost, and data privacy if devices are lost or stolen.
The document discusses the "camera in a pill", or capsule endoscopy. It provides a high-level overview of the technology, including that a pill-sized camera is swallowed to take images of the small intestine as it passes through. The camera transmits over 56,000 images wirelessly to a sensor array and data recorder worn on the body. The images can later be reviewed by a doctor on specialized software to diagnose conditions of the small intestine.
This document discusses optical computers, which use photons and light beams rather than electricity to perform computations. Optical computers offer advantages like immunity to electromagnetic interference, low transmission loss, large bandwidth, and parallel communication capabilities. They use components like VCSELs (vertical cavity surface emitting lasers) and photonic crystals to transmit and manipulate light for computations. While optical computers promise increased speeds, some challenges remain in miniaturizing optical components and addressing issues like interference from dust particles.
The document describes a pill-sized camera that can be swallowed to take pictures inside the digestive tract. It contains a camera, lights, transmitter and batteries inside a capsule. Over 50,000 color images are transmitted as it passes through the tract. Components include an optical dome, lens, LED lights, image sensor, battery and transmitter. The capsule is swallowed and images are transmitted to a receiver and computer for processing. It can diagnose conditions like Crohn's disease without surgery. Advantages are it is painless and provides high quality images of the small intestine. Drawbacks are it may get stuck if obstructions are present, though new bi-directional cameras aim to overcome this.
The document discusses a seminar presentation on mind reading computers. It begins with an introduction on how people express mental states through facial expressions and gestures. It then discusses what mind reading is, how it works using sensors to measure blood oxygen levels in the brain, and the process which involves facial detection and emotional classification techniques. Applications are discussed including using it to help paralyzed people communicate and potential issues around privacy breaches. It concludes that research is underway to allow computers to respond to brain activity.
This document describes an IoT-based health monitoring system created by three group members. The system uses sensors to measure a patient's heartbeat and temperature, which are sent wirelessly to a monitoring center. The monitoring center allows for real-time analysis of the vital sign data and emergency alerts. The system aims to allow doctors to remotely monitor patients at low cost using embedded technology.
The document describes a smart note taker product that allows users to take notes by writing in the air. The notes are sensed and stored digitally. Key features include allowing blind users to write freely, and enabling instructors to write notes during presentations that are broadcast to students. It works using sensors to detect 3D writing motions, which are processed, stored, and can be viewed on a display or sent to other devices. An applet program and database are used to recognize words written in the air and print them. The smart note taker offers advantages over digital pens like ease of use and time savings.
This document summarizes a minor project on a heart beat monitoring system. It discusses using a pulse oximetry sensor with an LED and LDR to detect heartbeats and interface it with a microcontroller and LCD to display the real-time heart rate. The system steps down household AC voltage to power the circuit and uses a voltage regulator to provide stable 5V power. It was developed using KEIL software and aims to provide a low-cost solution for heart rate monitoring, with potential applications in healthcare, fitness training, and telemedicine to remotely monitor multiple patients.
Pill Camera is a vitamin pill-sized capsule that travels through the human body taking pictures, helping diagnose a problem which previously would have been found only through surgery
The document describes Sixth Sense technology, a wearable gesture-based device that augments physical reality with digital information. It consists of a camera, projector, mirror, and mobile device. The camera tracks hand gestures and objects in view, sending data to the mobile device. The mobile device processes the data and searches the internet for relevant information. The projector then projects this digital information onto physical surfaces and objects, allowing users to interact seamlessly between the physical and digital worlds using natural hand gestures.
Screenless display is an evolving technology that allows information to be displayed or transmitted without the use of a physical screen or projector. There are three main types of screenless displays: visual image displays, which the eye can perceive; retinal direct displays, which project images directly onto the retina; and synaptic interfaces, which transmit visual information directly to the brain bypassing the eye. Major tech companies are working on applications of screenless displays to develop screenless laptops, TVs, and mobile phones that could benefit older or blind users. Benefits of screenless displays include lower power needs, higher resolution, greater portability, and the ability to present 3D images.
The document describes a finger-worn device called the FingerReader that assists visually impaired users in reading printed text. The FingerReader uses a small camera mounted on a 3D printed ring to scan and track text lines. It provides tactile and auditory feedback to help users smoothly track lines of text. The device aims to give visually impaired people more independence and access to printed materials than existing assistive technologies.
This document describes an obstacle avoiding robot with a vacuum cleaner. The robot uses IR sensors and a microcontroller to detect obstacles and navigate around them while using a blower to function as a vacuum cleaner. It discusses the components, circuit diagram, software, applications and future enhancements such as adding a camera to increase range or modifying it to function as a firefighting robot. The goal is to create a robot that can autonomously clean an area while avoiding obstacles.
Landmine detection using impulse ground penetrating radarPRADEEP Cheekatla
The document discusses landmine detection using ground penetrating radar (GPR). It begins with background on the landmine problem and existing detection technologies. It then provides a block diagram of the impulse GPR system, describing the impulse generator, antenna system, pulse extender, A/D converter, processor, and visual display. The document discusses implementation of the impulse GPR system and its applications in fields like engineering and military demining. It notes advantages like accurate measurements and ability to detect non-metallic mines, as well as limitations like false alarms. Future work aims to improve detection probabilities and scan rates.
pill camera/ capsule endoscopy used inn medical field to find out the abnormalities of small intestine. This replaced the convectional endoscopy method.
Home automation using google assistant ppt Somu Gupta
This document discusses using Google Assistant and IoT to control home appliances via voice commands. It introduces IoT and how connecting physical objects to the internet allows them to be controlled remotely. The author then explains how using Google Assistant and an IoT platform like Blynk, one can control devices like lights in their home just by speaking. The hardware and software setup is described, including a NodeMCU microcontroller, relay board, and connecting appliances to the relays for automated control through voice requests to the Assistant. Potential benefits of automation and future applications are also mentioned.
This document discusses place reminder applications, which are location-based services that provide reminders or alerts to users when they enter a specified geographical area. It provides examples of how place reminders can help users remember tasks at certain locations. The document then explains how place reminder applications work, using GPS to determine a user's location and trigger reminders. It highlights the advantages of place reminders being user-friendly, flexible, and helping users efficiently perform location-based tasks.
The document discusses the pill camera, which is a capsule-sized endoscopy device used to non-invasively examine the esophagus and small intestine. The pill camera contains a camera, light source, transmitter and batteries. It is swallowed and passes naturally through the digestive tract, transmitting over 50,000 images to an external recorder. Compared to conventional endoscopy, the pill camera offers a painless procedure without sedation that provides images of the entire small intestine. However, it cannot stop to examine areas of interest and cannot perform biopsies. The document reviews the capsule components, procedure, advantages of providing detailed images without risks of other methods, and applications in diagnosing gastrointestinal conditions.
With rapid development of economies, growth of aging population and the prevalence of chronic diseases across the world, there is an urgent need to find new ways to improve patient outcomes, increase access to care, and reduce the cost of medical care. A health care monitoring system is necessary to constantly monitor patient’s physiological parameters. The tele-medical system focuses on the measurement and evaluation of vital parameters e.g. temperature, electrocardiogram (ECG), heart rate variability, fall detection etc. This will enable doctors and care givers to observe patients without having to be physically present at their bedside, be it in the hospital or in their home.
Drowsiness is a critical factor impairing drivers’ performance in driving safely. There are several approaches in dealing with this issue based on human-machine interaction to detect drivers’ dozing off state, and then alert them to keep awake by sound or visual. These techniques fundamentally measure driver’s physical changes such as head angle, fatigue level and eyes states which are the indicators of drowsy state. However, they are limited in providing accurate and reliable results. Therefore, the project aims to achieve higher accuracy rate of drowsiness detection by using a very potential technology, electroencephalography (EEG) which is used widely in medical areas. Other than providing reliable result, the final product would bring more conveniences for customers with portability, easy-to-deploy and multi-device compatibility feature. In this project, its methodology first shows the strong correlation between drowsy state with brainwave frequency. Then a proposed system and testing plan are suggested based on the project objectives and available technologies. The final product is simply comprised of a hat with attached small electronic package used to record brainwave and a handheld device placing on dashboard of the car with an installed app. Finally, project management section will present in detail the human resources, scheduling, budget plan and risk analysis to show how it will be going to complete the project in six months.
This document discusses different types of mirrors and how they work. It explains that convex mirrors produce smaller, virtual images behind the mirror, while concave mirrors can produce either magnified real images or virtual images, depending on the object's distance from the mirror. The document also introduces ray diagrams as a tool to determine image characteristics like location, size, and whether the image is real or virtual.
This document discusses different types of mirrors and their properties. It distinguishes between concave and convex mirrors. Concave mirrors curve inward and focus light, producing real or virtual images depending on the object's distance. Convex mirrors curve outward and always produce smaller, upright, virtual images. Examples of uses for each type of mirror are given, including car headlights, security mirrors, and makeup mirrors. Real images are described as inverted while virtual images are upright. A diagram is also included to illustrate ray diagrams and image formation using mirrors.
Wearable technology refers to electronic devices that can be incorporated into items of clothing and accessories. Some examples include smart watches, fitness trackers, and Google Glass. Wearable devices perform similar tasks as mobile phones and computers by allowing hands-free use and constant access to features like notifications, activity tracking, and communication. While wearable technology provides benefits such as portability and mobility, challenges remain around potential health issues, cost, and data privacy if devices are lost or stolen.
The document discusses the "camera in a pill", or capsule endoscopy. It provides a high-level overview of the technology, including that a pill-sized camera is swallowed to take images of the small intestine as it passes through. The camera transmits over 56,000 images wirelessly to a sensor array and data recorder worn on the body. The images can later be reviewed by a doctor on specialized software to diagnose conditions of the small intestine.
This document discusses optical computers, which use photons and light beams rather than electricity to perform computations. Optical computers offer advantages like immunity to electromagnetic interference, low transmission loss, large bandwidth, and parallel communication capabilities. They use components like VCSELs (vertical cavity surface emitting lasers) and photonic crystals to transmit and manipulate light for computations. While optical computers promise increased speeds, some challenges remain in miniaturizing optical components and addressing issues like interference from dust particles.
The document describes a pill-sized camera that can be swallowed to take pictures inside the digestive tract. It contains a camera, lights, transmitter and batteries inside a capsule. Over 50,000 color images are transmitted as it passes through the tract. Components include an optical dome, lens, LED lights, image sensor, battery and transmitter. The capsule is swallowed and images are transmitted to a receiver and computer for processing. It can diagnose conditions like Crohn's disease without surgery. Advantages are it is painless and provides high quality images of the small intestine. Drawbacks are it may get stuck if obstructions are present, though new bi-directional cameras aim to overcome this.
The document discusses a seminar presentation on mind reading computers. It begins with an introduction on how people express mental states through facial expressions and gestures. It then discusses what mind reading is, how it works using sensors to measure blood oxygen levels in the brain, and the process which involves facial detection and emotional classification techniques. Applications are discussed including using it to help paralyzed people communicate and potential issues around privacy breaches. It concludes that research is underway to allow computers to respond to brain activity.
This document describes an IoT-based health monitoring system created by three group members. The system uses sensors to measure a patient's heartbeat and temperature, which are sent wirelessly to a monitoring center. The monitoring center allows for real-time analysis of the vital sign data and emergency alerts. The system aims to allow doctors to remotely monitor patients at low cost using embedded technology.
The document describes a smart note taker product that allows users to take notes by writing in the air. The notes are sensed and stored digitally. Key features include allowing blind users to write freely, and enabling instructors to write notes during presentations that are broadcast to students. It works using sensors to detect 3D writing motions, which are processed, stored, and can be viewed on a display or sent to other devices. An applet program and database are used to recognize words written in the air and print them. The smart note taker offers advantages over digital pens like ease of use and time savings.
This document summarizes a minor project on a heart beat monitoring system. It discusses using a pulse oximetry sensor with an LED and LDR to detect heartbeats and interface it with a microcontroller and LCD to display the real-time heart rate. The system steps down household AC voltage to power the circuit and uses a voltage regulator to provide stable 5V power. It was developed using KEIL software and aims to provide a low-cost solution for heart rate monitoring, with potential applications in healthcare, fitness training, and telemedicine to remotely monitor multiple patients.
Pill Camera is a vitamin pill-sized capsule that travels through the human body taking pictures, helping diagnose a problem which previously would have been found only through surgery
The document describes Sixth Sense technology, a wearable gesture-based device that augments physical reality with digital information. It consists of a camera, projector, mirror, and mobile device. The camera tracks hand gestures and objects in view, sending data to the mobile device. The mobile device processes the data and searches the internet for relevant information. The projector then projects this digital information onto physical surfaces and objects, allowing users to interact seamlessly between the physical and digital worlds using natural hand gestures.
Screenless display is an evolving technology that allows information to be displayed or transmitted without the use of a physical screen or projector. There are three main types of screenless displays: visual image displays, which the eye can perceive; retinal direct displays, which project images directly onto the retina; and synaptic interfaces, which transmit visual information directly to the brain bypassing the eye. Major tech companies are working on applications of screenless displays to develop screenless laptops, TVs, and mobile phones that could benefit older or blind users. Benefits of screenless displays include lower power needs, higher resolution, greater portability, and the ability to present 3D images.
The document describes a finger-worn device called the FingerReader that assists visually impaired users in reading printed text. The FingerReader uses a small camera mounted on a 3D printed ring to scan and track text lines. It provides tactile and auditory feedback to help users smoothly track lines of text. The device aims to give visually impaired people more independence and access to printed materials than existing assistive technologies.
This document describes an obstacle avoiding robot with a vacuum cleaner. The robot uses IR sensors and a microcontroller to detect obstacles and navigate around them while using a blower to function as a vacuum cleaner. It discusses the components, circuit diagram, software, applications and future enhancements such as adding a camera to increase range or modifying it to function as a firefighting robot. The goal is to create a robot that can autonomously clean an area while avoiding obstacles.
Landmine detection using impulse ground penetrating radarPRADEEP Cheekatla
The document discusses landmine detection using ground penetrating radar (GPR). It begins with background on the landmine problem and existing detection technologies. It then provides a block diagram of the impulse GPR system, describing the impulse generator, antenna system, pulse extender, A/D converter, processor, and visual display. The document discusses implementation of the impulse GPR system and its applications in fields like engineering and military demining. It notes advantages like accurate measurements and ability to detect non-metallic mines, as well as limitations like false alarms. Future work aims to improve detection probabilities and scan rates.
pill camera/ capsule endoscopy used inn medical field to find out the abnormalities of small intestine. This replaced the convectional endoscopy method.
Home automation using google assistant ppt Somu Gupta
This document discusses using Google Assistant and IoT to control home appliances via voice commands. It introduces IoT and how connecting physical objects to the internet allows them to be controlled remotely. The author then explains how using Google Assistant and an IoT platform like Blynk, one can control devices like lights in their home just by speaking. The hardware and software setup is described, including a NodeMCU microcontroller, relay board, and connecting appliances to the relays for automated control through voice requests to the Assistant. Potential benefits of automation and future applications are also mentioned.
This document discusses place reminder applications, which are location-based services that provide reminders or alerts to users when they enter a specified geographical area. It provides examples of how place reminders can help users remember tasks at certain locations. The document then explains how place reminder applications work, using GPS to determine a user's location and trigger reminders. It highlights the advantages of place reminders being user-friendly, flexible, and helping users efficiently perform location-based tasks.
The document discusses the pill camera, which is a capsule-sized endoscopy device used to non-invasively examine the esophagus and small intestine. The pill camera contains a camera, light source, transmitter and batteries. It is swallowed and passes naturally through the digestive tract, transmitting over 50,000 images to an external recorder. Compared to conventional endoscopy, the pill camera offers a painless procedure without sedation that provides images of the entire small intestine. However, it cannot stop to examine areas of interest and cannot perform biopsies. The document reviews the capsule components, procedure, advantages of providing detailed images without risks of other methods, and applications in diagnosing gastrointestinal conditions.
With rapid development of economies, growth of aging population and the prevalence of chronic diseases across the world, there is an urgent need to find new ways to improve patient outcomes, increase access to care, and reduce the cost of medical care. A health care monitoring system is necessary to constantly monitor patient’s physiological parameters. The tele-medical system focuses on the measurement and evaluation of vital parameters e.g. temperature, electrocardiogram (ECG), heart rate variability, fall detection etc. This will enable doctors and care givers to observe patients without having to be physically present at their bedside, be it in the hospital or in their home.
Drowsiness is a critical factor impairing drivers’ performance in driving safely. There are several approaches in dealing with this issue based on human-machine interaction to detect drivers’ dozing off state, and then alert them to keep awake by sound or visual. These techniques fundamentally measure driver’s physical changes such as head angle, fatigue level and eyes states which are the indicators of drowsy state. However, they are limited in providing accurate and reliable results. Therefore, the project aims to achieve higher accuracy rate of drowsiness detection by using a very potential technology, electroencephalography (EEG) which is used widely in medical areas. Other than providing reliable result, the final product would bring more conveniences for customers with portability, easy-to-deploy and multi-device compatibility feature. In this project, its methodology first shows the strong correlation between drowsy state with brainwave frequency. Then a proposed system and testing plan are suggested based on the project objectives and available technologies. The final product is simply comprised of a hat with attached small electronic package used to record brainwave and a handheld device placing on dashboard of the car with an installed app. Finally, project management section will present in detail the human resources, scheduling, budget plan and risk analysis to show how it will be going to complete the project in six months.
This document discusses different types of mirrors and how they work. It explains that convex mirrors produce smaller, virtual images behind the mirror, while concave mirrors can produce either magnified real images or virtual images, depending on the object's distance from the mirror. The document also introduces ray diagrams as a tool to determine image characteristics like location, size, and whether the image is real or virtual.
This document discusses different types of mirrors and their properties. It distinguishes between concave and convex mirrors. Concave mirrors curve inward and focus light, producing real or virtual images depending on the object's distance. Convex mirrors curve outward and always produce smaller, upright, virtual images. Examples of uses for each type of mirror are given, including car headlights, security mirrors, and makeup mirrors. Real images are described as inverted while virtual images are upright. A diagram is also included to illustrate ray diagrams and image formation using mirrors.
The document describes a paper thin film battery that is self-rechargeable. It discusses the manufacturing of carbon nanotubes and the development of paper batteries. Experimental details are provided on testing the dependence of discharge capacity on temperature and the typical series connection method. Results show the battery output is independent of electrode thickness but depends strongly on relative humidity. Applications of paper batteries in cosmetics are discussed.
Light is an electromagnetic wave that can be reflected, absorbed, or refracted. The law of reflection states that the angle of incidence equals the angle of reflection. Mirrors can form either real or virtual images. Concave mirrors focus parallel light rays to a focal point, forming real, inverted, and reduced images between the focal point and center of curvature. The mirror equation and magnification equation can be used to calculate the location and characteristics of an image formed by a spherical mirror.
The document proposes a secure mobile-based voting system that allows voters to cast their votes from anywhere using a mobile device. It outlines the existing electronic and ballot-based voting systems and their drawbacks. The proposed system uses speech recognition and a three-tier architecture to authenticate voters and securely collect, count, and store votes. It aims to improve accessibility, participation, and reduce costs compared to traditional voting methods.
This circuit comprises an infrared (IR) transmitter unit and receiver unit that are mounted on opposite gate pillars. When the IR beam between the units is interrupted, a melody is triggered to sound for 30 seconds from the receiver unit to alert someone that someone is at the gate. The transmitter unit uses a 38kHz IR LED and timer to transmit the IR beam. The receiver unit uses an IR sensor and timer connected to a melody generator IC to detect the beam interruption and play the melody. The units are powered separately but connected to allow the receiver to trigger when the beam is blocked.
Silent Sound Technology is a new technology being developed that allows communication without making any sound. It works by using electromyography sensors to detect tiny muscle movements in the face when speaking, and converts those signals into electrical pulses that can be transformed into speech. It also uses image processing of lip movements to analyze the spoken words and transmit the audio to the other person on the call. This technology has potential applications for silent phone calls, helping those who have lost their voice, and secret military communications. However, it still faces challenges with translation, security, and practical usability due to the sensors currently needing to be attached to the face.
Seminar report on solar tree (by Vikas)dreamervikas
Now a days with the growing population and energy demand we should take a renewable option of energy source and also we should keep in mind that energy should not cause pollution and other natural hazards. In this case the solar energy is the best option for us.
so based on solar energy the solar tree is formed and it acquire very less land.
The capsule camera is a pill-sized device that can be swallowed to take pictures of the digestive tract as it passes through. It contains a camera, lights, transmitter and batteries. Images are transmitted wirelessly to a recorder and over 2,600 high quality images can be captured. The capsule allows non-invasive imaging of the small intestine to diagnose conditions like Crohn's disease. It is painless for the patient but cannot be controlled and could get obstructed, though newer models aim to overcome these limitations. The capsule camera has revolutionized digestive imaging.
‘Bubble Power’-the revolutionary new energy source. It is working under the principle of Sonofusion.Sonofusion involves tiny bubbles imploded by sound waves that can make hydrogen nuclei fuse and may one day become a revolutionary new energy source.
The Medical Mirror is an interactive interface that tracks and displays a user's heart rate in real time without external sensors. It consists of an LCD monitor with a built-in webcam connected to analysis software that projects information onto the mirror's reflective surface. The mirror uses light to noninvasively measure heart rate from a person's reflection in real-time, allowing for remote health monitoring simply by looking in the mirror.
This document discusses the author's theory that human intelligence and biological processes are stored and carried out using "minions" in the brain and cells. The minions are complexes of DNA bound to protein sheets that can store information via arrays of proton-ordered hydrogen bonds. Each minion stores an 18-letter word using a 63-character alphabet. Billions of minions working together in cell nuclei could store vast amounts of information like the entire works of Shakespeare. The minions also function as biological clocks and are proposed to explain phenomena like muscle contraction, photosynthesis, cell division and the origin of life.
This document discusses various aspects of digital citizenship including digital safety, etiquette, rights and responsibilities, and cyberbullying. It provides questions to prompt thinking about keeping personal information private and secure online, using appropriate language, what cyberbullying is, how it occurs and its negative impacts, as well as how individuals and schools can address it.
This document describes a study that investigated extracting heart rate from video data in a non-contact way. The study recorded video of 3 subjects' faces at rest, during physical activity, and after resting. It analyzed the videos to extract the heart rate signal from changes in skin color over time. It found that the extracted heart rates matched expectations, falling within normal ranges at rest, elevated during activity, and lowering after resting. The study demonstrated the feasibility of non-contact heart rate measurement via video analysis.
This document outlines a presentation on cloud storage. It begins with definitions of cloud storage, including that data is stored on servers owned by hosting companies and accessed via APIs. The history of cloud storage from the 1960s to modern services like Dropbox is discussed. Advantages include easy sharing of files, large storage capacity, and online editing. Potential concerns cited are security, technical problems, and unclear data ownership. Applications include personal, public, business and hybrid cloud storage. The conclusion is that cloud storage brings convenience but users should be aware of security risks, and its use will likely continue increasing.
This document discusses Blue Brain technology and the goal of creating an artificial brain using silicon chips. It aims to upload the contents of a natural human brain into a virtual brain. This would allow human intelligence, memories, and personalities to potentially persist after death through the virtual brain. The document outlines how nanobots could scan a human brain at a cellular level and transfer that information to a supercomputer to recreate the brain's structure and function virtually. It compares key aspects of natural and virtual brains, such as how inputs, interpretation, outputs, memory, and processing would theoretically work for a virtual brain modeled after the human brain.
Supercapacitors or EDLCs (i.e. electric double-layer capacitors) or ultra-capacitors are becoming increasingly popular as alternatives for the conventional and traditional battery sources. This brief overview focuses on the different types of supercapacitors, the relevant quantitative modeling areas and the future of supercapacitor research and development. Supercapacitors may emerge as the solution for many application-specific power systems. Especially, there has been great interest in developing supercapacitors for electric vehicle hybrid power systems, pulse power applications, as well as back-up and emergency power supplies. Because of their flexibility, however, supercapacitors can be adapted to serve in roles for which electrochemical batteries are not as well suited. Also, supercapacitors have some intrinsic characteristics that make them ideally suited to specialized roles and applications that complement the strengths of batteries. In particular, supercapacitors have great potential for applications that require a combination of high power, short charging time, high cycling stability and long shelf life. So, let’s just begin the innovative journey of these near future of life-long batteries that can charge up almost anything and everything within a few seconds!
This document discusses how machine learning can help people stay healthy by analyzing biometric data from wearable devices. It explains that measuring factors like temperature, heart rate, and activity level can provide insights to form good health habits. Machine learning algorithms like K-means clustering are applied to this biometric data to recognize patterns and activities. While a basic sample model is created, the document outlines ways to improve it, such as using more data, other algorithms, and ensembles of models. Overall, the document demonstrates the potential of machine learning and quantified self-tracking to provide health and wellness insights.
This document provides a 3-page summary of a seminar report on non-contact heart rate measurement using photoplethysmography. It begins with an introduction describing the motivation and challenges of non-contact heart rate measurement. It then provides background on topics such as resting heart rate measurement, photoplethysmography, and the use of blind source separation to remove motion artifacts. The experimental setup used a basic webcam to record videos of faces that were then analyzed to compute heart rate measurements in a non-contact manner.
The document summarizes various monitoring devices used during anesthesia, including essential monitors like ECG, non-invasive blood pressure, pulse oximetry, capnography, and vapor concentration analyzers. It also discusses immediately available monitors like peripheral nerve stimulators and temperature monitors. Additional monitors that may be required in some cases include invasive blood pressure, urine output, central venous pressure, pulmonary artery pressure, and cardiac output, which can be measured using a pulmonary artery catheter.
3 procedures regarding the cardiovascular system chapter 5mark
This document discusses 3 types of diagnostic procedures for the cardiovascular system: stress tests, Holter monitors, and measuring cardiac enzymes via blood testing. It describes 3 common types of stress tests - treadmill tests, dobutamine or adenosine tests, and stress echocardiograms. It also explains how Holter monitors can continuously monitor heart activity over hours or days. Finally, it details how measuring levels of cardiac enzymes in the blood can indicate heart muscle damage from events like heart attacks.
This document discusses an assessment tool that evaluates the autonomic nervous system and cardiovascular system through non-invasive tests of sudomotor function, endothelial function, and cardiac autonomic reflex tests. It can help with early detection of peripheral neuropathy, cardiac autonomic neuropathy, and cardiovascular disease risk. The tool includes tests of galvanic skin response to assess sudomotor function, photoplethysmography to evaluate heart rate variability and blood pressure response, and challenges like Valsalva maneuver and deep breathing to assess sympathetic and parasympathetic function. Overall, it provides a method to evaluate autonomic nervous system integrity and risks for various neuropathies and diseases.
Two phase heart disease diagnosis system using deep learningSHAMIK TIWARI
This document summarizes a research paper that presents a two-phase system for diagnosing heart disease using deep learning. In the first phase, clinical data is used to identify the likelihood of cardiovascular problems. For positive results, electrocardiogram (ECG) signals are then analyzed in the second phase to classify heart rhythms and diagnose specific heart conditions. Deep neural networks are employed in this integrated approach. The results confirm the robustness of the proposed two-phase heart disease diagnosis model.
This document presents a two-phase heart disease diagnosis system using deep learning. In the first phase, clinical data is used to identify the likelihood of cardiovascular problems. For positive results, electrocardiogram (ECG) signals are then used in the second phase to classify heart rhythms and diagnose specific heart diseases. Deep neural networks are employed in both phases. The proposed integrated approach confirms the robustness of using clinical data and ECG analysis together with deep learning for accurate heart disease diagnosis.
This document proposes a method to detect pulse from head motions in videos. It aims to provide non-invasive heart rate monitoring by tracking subtle head oscillations that accompany the cardiac cycle. The method analyzes video recordings of a person's head movements to extract information about cardiac activity. It uses feature tracking, frequency filtering, and principal component analysis to identify the head motion component corresponding to pulse. Heart rate and individual heartbeats are then determined by examining the frequency spectrum and detecting peaks in the motion trajectory.
The term Arrhythmia refers to any change from the normal sequence in the electrical impulses. It is also treated as abnormal heart rhythms or irregular heartbeats. The rate of growth of Cardiac Arrhythmia disease is very high & its effects can be observed in any age group in society. Arrhythmia detection can be done in many ways but effective & simple method for detection & diagnosis of Cardiac Arrhythmia is by doing analysis of Electrocardiogram signals from ECG sensors. ECG signal can give us the detail information of heart activities, so we can use ECG signals to detect the rhythm & behaviour of heart beats resulting into detection & diagnosis of Cardiac Arrhythmia. In this paper new & improved methodology for early Detection & Classification of Cardiac Arrhythmia has been proposed. In this paper ECG signals are captured using ECG sensors & this ECG signals are used & processed to get the required data regarding heart beats of the human being & then proposed methodology applies for Detection & Classification of Cardiac Arrhythmia. Detection of Cardiac Arrhythmia using ECG signals allows us for easy & reliable way with low cost solution to diagnose Arrhythmia in its prior early stage.
Insight into Monitoring of the surgical patientlmdm11
Pulse oximetry, ECG, and blood pressure monitoring are common ways to assess patients. A pulse oximeter uses light absorption to estimate oxygenated and deoxygenated hemoglobin levels non-invasively. An ECG attaches electrodes to record the heart's electrical activity and indicates rate, rhythm, and signs of ischemia. Blood pressure results from cardiac contraction and vascular resistance, and can be measured manually or via an arterial line that displays beat-to-beat variations to assess contractility, tone, and response to interventions.
Cardiac arrest is the sudden loss of heart function and can be caused by coronary heart disease, arrhythmias, or other factors like respiratory arrest or trauma. Without treatment within 4-6 minutes, brain death and permanent death can occur, so early CPR and defibrillation are crucial to restore normal heart rhythm and improve chances of survival. Widespread availability of AEDs and higher bystander CPR rates could save tens of thousands more lives each year from sudden cardiac arrest.
Cardiac arrest is the sudden loss of heart function and can be caused by coronary heart disease, arrhythmias, or other factors like respiratory arrest or trauma. Without treatment within 4-6 minutes, brain death and permanent death can occur, so early CPR and defibrillation are crucial to restore normal heart rhythm and improve chances of survival. Widespread availability of AEDs and increased bystander CPR rates could save tens of thousands more lives each year from sudden cardiac arrest.
Home Care Heart Diagnosis and Measurement of Biological Signals Using Intelli...ijsrd.com
the importance behind this work is the development of intelligent, accurate diagnosis of heart rate using blood pressure. BP is the parameter which does not abide by a single range, but it depends upon the factors like age, family history. By using blood pressure system, heart rate of a person is measured. At the present situation the mortality rate has been increased due to rise in blood pressure and heart malfunctions. A Biosensor is used in forth to detect the range of heart rate. Intelligent system used here is fuzzy system which takes age, gender, BMI for the verification. Lab view is other end of the project which is used to connect the hardware to show the progress of measurement. Parameters such as Smoke detection, Temperature measurement, unauthorized entry were are included for additional facilities.
The document provides an overview of cardiovascular disorders and the nursing care of clients with such conditions. It discusses the anatomy and physiology of the heart, epidemiology of cardiovascular diseases, nursing assessment including history, physical exam, diagnostic tests, and monitoring tools. Nursing responsibilities are outlined for various diagnostic tests and procedures like stress tests, echocardiograms, cardiac catheterization, and treatment of dysrhythmias. The goal of nursing care is to comprehensively assess and monitor clients while educating them about risk factor reduction and management of their cardiovascular condition.
This document outlines recommendations from a symposium on stroke management organized by the European Federation of Neurological Societies. It covers recommendations for organizing stroke care, risk factors and primary prevention, acute stroke care including general therapy, specific therapies, rehabilitation, and secondary prevention. Key recommendations include treating patients in specialized stroke units, initiating thrombolysis within 3 hours of onset for ischemic stroke, and controlling risk factors like hypertension, diabetes, hypercholesterolemia and smoking to prevent primary strokes.
Cardiomyopathy (KAR-de-o-mi-OP-ah-thee) refers to diseases of the heart muscle. These diseases have many causes, signs and symptoms, and treatments.
In cardiomyopathy, the heart muscle becomes enlarged, thick, or rigid. In rare cases, the muscle tissue in the heart is replaced with scar tissue.
As cardiomyopathy worsens, the heart becomes weaker. It's less able to pump blood through the body and maintain a normal electrical rhythm. This can lead toheart failure or irregular heartbeats called arrhythmias (ah-RITH-me-ahs). In turn, heart failure can cause fluid to build up in the lungs, ankles, feet, legs, or abdomen.
The weakening of the heart also can cause other complications, such as heart valve problems.
OverviewThe main types of cardiomyopathy are:
Dilated cardiomyopathy
Hypertrophic (hi-per-TROF-ik) cardiomyopathy
Restrictive cardiomyopathy
Arrhythmogenic (ah-rith-mo-JEN-ik) right ventricular dysplasia
(dis-PLA-ze-ah)
Other types of cardiomyopathy sometimes are referred to as "unclassified cardiomyopathy."
Cardiomyopathy can be acquired or inherited. "Acquired" means you aren't born with the disease, but you develop it due to another disease, condition, or factor. "Inherited" means your parents passed the gene for the disease on to you. Many times, the cause of cardiomyopathy isn't known.
Cardiomyopathy can affect people of all ages. However, people in certain age groups are more likely to have certain types of cardiomyopathy. This article focuses on cardiomyopathy in adults.
OutlookSome people who have cardiomyopathy have no signs or symptoms and need no treatment. For other people, the disease develops quickly, symptoms are severe, and serious complications occur.
Treatments for cardiomyopathy include lifestyle changes, medicines, surgery, implanted devices to correct arrhythmias, and a nonsurgical procedure. These treatments can control symptoms, reduce complications, and stop the disease from getting worse.
National Heart Lung and Blood Institute
Cardiovascular Diagnostic Procedures by Nadia AbdulallahNadia Abdulallah
Cardiovascular diagnostic procedures include blood tests, stress tests, electrocardiography (EKG), and echocardiography. Blood tests measure cardiac enzyme and troponin levels to determine if a heart attack has occurred. Stress tests evaluate cardiovascular fitness by monitoring the patient's heart rate and oxygen levels during increasing physical exertion. EKGs record the heart's electrical activity over time through external electrodes. Echocardiography uses ultrasound imaging to visualize the heart's internal structures and assess conditions like valve diseases or blood flow abnormalities.
The ASA guidelines establish standards for basic anesthesia monitoring. Standard I requires qualified anesthesia personnel to be present throughout all general and regional anesthetics. Standard II requires the patient's oxygenation, ventilation, circulation, and temperature to be continually evaluated during all anesthetics.
The document then discusses the history and value of monitoring patients during anesthesia. It notes that 25 years ago the most basic form of monitoring was continuous palpation of the radial pulse throughout surgery. Modern monitors make monitoring easier but clinical judgment is still most valuable. Basic required monitors are ECG, SpO2, blood pressure, and sometimes capnography.
Patient monitoring involves both non-instrumental and instrumental assessment. Non-instrumental monitoring includes visual observation of factors like respiratory pattern, bleeding, and IV lines. Instrumental monitoring provides quantitative data through devices like ECG, blood pressure cuffs, pulse oximetry, capnography, and muscle relaxation monitors. Together, non-instrumental and instrumental monitoring provide clinicians with vital information about patients' physiological status to guide care in settings like operating rooms and intensive care.
This lesson plan provides information on cardiac tamponade. The objectives are for students to understand cardiac tamponade, including defining it, listing causes, and discussing manifestations and treatments. The plan outlines topics on the anatomy and physiology of the heart, definition of tamponade, causes such as chest injury and infection, signs including low blood pressure and muffled heart sounds, diagnostic tests like echocardiogram, and treatments such as pericardiocentesis to drain fluid from the pericardium. Reflective, research-based, interactive and contextual learning activities are also included.
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NURSING MANAGEMENT OF PATIENT WITH EMPHYSEMA .PPTblessyjannu21
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Emphysema is a disease condition of respiratory system.
Emphysema is an abnormal permanent enlargement of the air spaces distal to terminal bronchioles, accompanied by destruction of their walls and without obvious fibrosis.
Emphysema of lung is defined as hyper inflation of the lung ais spaces due to obstruction of non respiratory bronchioles as due to loss of elasticity of alveoli.
It is a type of chronic obstructive
pulmonary disease.
It is a progressive disease of lungs.
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Medical mirror report
1. Chapter 1
Introduction
Regular and non-invasive assessments of cardiovascular function are
important insurveillance for cardiovascular catastrophes and treatment
therapies of chronic diseases.Resting heart rate, one of the simplest
cardiovascular parameters, has been identified as anindependent risk
factor (comparable with smoking, dyslipidemia or hypertension)
for cardiovascular disease [1]. Currently, the gold standard techniques
for measurement of thecardiac pulse such as the electrocardiogram
(ECG) require patients to wear adhesive gel patches or chest straps
that can cause skin irritation and discomfort. Commercial
pulseoximetry sensors that attach to the fingertips or earlobes are also
inconvenient for patientsand the spring-loaded clips can cause pain if worn
over a long period oftime.The ability to monitor a patient¶s physiological
signals by a remote, non-contactmeans is a tantalizing prospect that
would enhance the delivery of primary healthcare. For example, the
idea of performing physiological measurements on the face was first
postulated by Pavlidis and associates [2] and later demonstrated
through analysis of facial thermalvideos. Although non-contact
methods may not be able to provide details concerning
cardiacelectrical conduction that ECG offers, these methods can now
enable long-term monitoring of other physiological signals such as
heart rate or respiratory rate by acquiring themcontinuously in an
unobtrusive and comfortable manner.Beyond that, such a technology
would also minimize the amount of cabling andclutter associated with
neonatal ICU monitoring, long-term epilepsy monitoring, burn
or trauma patient monitoring, sleep studies, and other cases where a continuous
measure ofheart-rate is important. The use of photoplethysmography
(PPG), a low cost and non-invasivemeans of sensing the
cardiovascular pulse wave (also called the blood volume pulse)
throughvariations in transmitted or reflected light, for non-contact
physiological measurements has been investigated recently. This
electro-optic technique can provide valuable informationabout the
cardiovascular system such as heart rate, arterial blood oxygen
saturation, blood pressure, cardiac output and autonomic function.
2. Typically, PPG has always been implemented using dedicated
light sources (e.g. redand/or infra-red wavelengths), but recent work
has shown that pulse measurements can beacquired using digital
camcorders/cameras with normal ambient light as the
illuminationsource. However, all these previous efforts lacked
rigorous physiological and mathematicalmodels amenable to
computation; they relied instead on manual segmentation and
heuristicinterpretation of raw images with minimal validation of
performance characteristics.Furthermore, PPG is known to be
susceptive to motion-induced signal corruption andovercoming
motion artifacts presents one of the most challenging problems. In
most cases,thenoisefallswithinthesamefrequency bandasthephysiological
signal of interest, thusrendering linear filtering with fixed cut-off
frequencies ineffective. In order to develop aclinically useful
technology, there is a need for ancillary functionality such as motion
artifactsreduction through efficient and robust image analysis.One
technique for noise removal from physiological signals is blind source
separation(BSS). BSS refers to the recovery of unobserved signals or
³sources´ from a set of observedmixtures with no prior information
about mixing process. Typically, the observations areacquired from
the output of a set of sensors, where each sensor receives a
differentcombination of the source signals. There are several
methods of BSS and in this paper wewill focus on BSS by
Independent Component Analysis (ICA). ICA is a technique
for uncovering the independent source signals from a set of
observations that are composed of linear mixtures of the underlying
sources. ICA has also been applied to reduce motionartifacts in PPG
measurements.In this topic, a novel methodology for non-contact,
automated, and motion tolerantcardiac pulse measurements from
video images based on blind source separation. Firstly, theapproach
is described and it is applied to compute heart rate measurements
from videoimages of the human face recorded using a simple
webcam. Secondly, we demonstrate howthis method can tolerate
motion artifacts and validate the accuracy of this approach with
anFDA-approved finger blood volume pulse (BVP) measurement device.
3. Thirdly, we showhow this method can be easily extended for
simultaneous heart rate measurements of multiple persons.
4. Chapter 2
Resting Heart Rate
Heart rate is the number of heartbeats per unit of time, typically expressed as
beats per minute
(bpm) [3]. Heart rate can vary as the body's need to absorb oxygen
and excrete carbondioxide changes, such as during exercise or sleep.
The measurement of heart rate is used bymedical professionals to
a
ssist in the diagnosis and tracking of medical conditions. It is alsoused
by individuals, such as athletes, who are interested in monitoring their
heart rate to gainmaximum efficiency from their training. The R wave
to R wave interval (RR interval) is theinverse ofthe heart rate.
2.1 Measurement of Heart Rate
Heart rate is measured by finding the pulse of the body. This pulse
rate can be measured atany point on the body where the artery's
pulsation is transmitted to the surface by pressuringit with the index
and middle fingers; often it is compressed against an underlying
structurelike bone. The thumb should not be used for measuring another
person's heart rate, as itsstrong pulse mayinterfere with discriminating the site of
pulsation.Possible points for measuring the heart rate are:1. The ventral
aspect of the wrist on the side of the thumb (radial artery).2. The ulnar artery.3.
The neck (carotid artery).4. The inside of the elbow, or under the biceps
muscle (branchial artery).5. The groin (femoral artery).6. Behind the
medial malleolus on the feet (posterior tibial artery).7. Middle of dorsum
of the foot (dorsalis pedis).8. Behind the knee (popliteal artery).9. Over
the abdomen (abdominal aorta).A more precise method of determining
pulse involves the use of anelectrocardiograph, or EKG (also abbreviated
EKG). Continuous electrocardiographmonitoring of the heart is
routinely done in many clinical settings, especially in critical care
medicine. Commercial heart rate monitors are also available,
consisting of a chest strap withelectrodes. The signal is transmitted to
a wrist receiver for display. Heart rate monitors allowaccurate
measurements to be taken continuously and can be used during
exercise whenmanual measurement would be difficult or impossible (such as
when thehands are beingused).
5. 2.2 Measurements at Rest
The resting heart rate (HRrest) is a person's heart rate when they are at
rest, that is lying down but awake, and not having recently exerted
themselves. The typical healthy resting heart ratein adults is 60±80
bpm , with rates below 60 bpm referred to as bradycardia, and rates
above100 bpm referred to as tachycardia. Note however that
conditioned athletes often have restingheart rates below 60 bpm. Cyclist
Lance Armstrong had a resting HR around 32 bpm, and itis not unusual for
people doing regular exercise to get below 50 bpm. Other cyclists
likeMiguel Indurain also have a very low heart rate at rest (29 bpm).
Musical tempo terms reflectlevels relative to resting heart rate;
Adagio
(at ease, at rest) is typically 66±76 bpm, similar tohuman resting heart
rate, while Lento
and Largo
("Slow") are 40±60 bpm, which reflects thatthese tempi are slow
relative to normal human heart rate. Similarly, faster tempi
correspondto heart rates at higher levels of exertion, such as Andante
(walking: 76±108bpm)and thelike.
The normal heart rate in children is variable and depends on the
child's age. The rangesthat should be considered normal are
controversial.
2.3 Abnormalities
2.3.1Tachycardia
Tachycardia is a resting heart rate more than 100 beats per minute.
This number can vary assmaller people and children have faster heart
rates than average adults.
2.3.2 Bradycardia
Bradycardia is defined as a heart rate less than 60 beats per minute
although it is seldomsymptomatic until below 50 bpm when a human
is at total rest. Trained athletes tend to haveslow resting heart rates,
and resting bradycardia in athletes should not be consideredabnormal
6. if the individual has no symptoms associated with it. For example
Miguel Indurain,a Spanish cyclist and five time Tour de France
winner, had a resting heart rate of 29 beats per minute, one of the
lowest ever recorded in a healthy human. Again, this number can vary
aschildren and small adults tend to have faster heart rates than average
adults.
2.3.3 Arrhythmia
Arrhythmias are abnormalities of the heart rate and rhythm
(sometimes felt as palpitations).They can be divided into two broad
categories: fast and slow heart rates. Some cause few or minimal
symptoms. Others produce more serious symptoms of lightheadedness,
dizzinessand fainting.
2.4 Heart Rate as a Risk Factor
A number of investigations indicate that faster resting heart rate has
emerged as a new risk factor for mortality in homeothermic
mammals, particularly cardiovascular mortality inhuman beings.
Faster heart rate may accompany increased production of
inflammationmolecules and increased production of reactive oxygen
species in cardiovascular system, inaddition to increased mechanical
stress to the heart. There is a correlation between increasedresting rate
and cardiovascular risk. This is not seen to be "using an allotment of
heart beats" but rather an increased risk to the system from the
increased rate. An Australian-ledinternational study of patients with
cardiovascular disease has shown that heart beat rate is akey indicator
forthe riskofheart attack. The study, published in
TheLancet
(September 2008) studied 11,000 people, across 33 countries, who
were being treated for heart problems.Those patients whose heart rate was
above 70 beats per minute had significantly higher incidence of heart attacks,
hospital admissions and the need for surgery.
7. Chapter 3
Photoplethysmography
3.1 Photoplethysmography
A photoplethysmography [4] (PPG) is an optically obtained
plethysmograph, a volumetricmeasurement of an organ. A PPG is
often obtained by using a pulse oximeter whichilluminates the skin and
measures changes in light absorption. A conventional pulse oximeter monitors
the perfusion of blood to the dermis and subcutaneous tissue of the
skin. With eachcardiac cycle the heart pumps blood to the periphery.
Even though this pressure pulse issomewhat damped by the time it reaches
the skin, it is enough to distend the arteries andarterioles in the subcutaneous
tissue.
Figure 3.1Representative PPG taken from an ear pulse oximeter.
If the pulse oximeter is attached without compressing the skin, a
pressure pulse canalso be seen from the venous plexus, as a small
secondary peak. The change in volumecaused by the pressure pulse is
detected by illuminating the skin with the light from a light-emitting
diode (LED) and then measuring the amount of light either
transmitted or reflectedto a photodiode. Each cardiac cycle appears as
a peak, as seen in the figure. Because bloodflow to the skin can be
modulated by multiple other physiological systems, the PPG can also
7
8. be used to monitor breathing, hypovolemia, and other circulatory
conditions. Additionally,the shape of the PPG waveform differs from
subject to subject, and varies with the locationand manner in which the
pulseoximeter [5]isattached.
3.2 Sites for Measuring PPG
While pulse oximeters are a commonly used medical device the PPG
derived from them israrely displayed, and is nominally only processed
to determine heart rate. PPGs can beobtained from transmissive
absorption (as at the finger tip) or reflective (as on the forehead).In
outpatient settings, pulse oximeters are commonly worn on the finger.
However, in casesof shock, hypothermia, etc. blood flow to the
periphery can be reduced, resulting in a PPGwithout a discernible
cardiac pulse. In this case, a PPG can be obtained from a pulse
oximeter on the head, with the most common sites being the ear, nasal
septum, and forehead. PPGs canalso be obtained from the vagina and
esophagus.
3.3UsesofPhotoplesmography
3.3.1 Monitoring Heart Rate and Cardiac Cycle
Because the skin is so richly perfused, it is relatively easy to detect
the pulsatile componentof the cardiac cycle. The DC component of
the signal is attributable to the bulk absorption of the skin tissue,
while the AC component is directly attributable to variation in blood
volumein the skin caused bythe pressure pulse of the cardiac cycle. The height
of AC component of the photoplethysmogram is proportional to the
pulse pressure, the difference between thesystolic and diastolic
pressure in the arteries. As seen in the figure showing
prematureventricular contractions (PVCs), the PPG pulse for the
cardiac cycle with the PVC results inlower amplitude blood pressure
and a PPG. Ventricular tachycardia and ventricular fibrillation can
also be detected.
3.3.2 Monitoring Respiration
Respiration affects the cardiac cycle by varying the intrapleural
pressure, the pressure between the thoracic wall and the lungs. Since
the heart resides in the thoracic cavity betweenthe lungs, the partial
pressure of inhaling and exhaling greatly influence the pressure on
thevena cava and the filling of the right atrium. This effect is often
referred to as normal sinus arrhythmia. During inspiration,
9. intrapleural pressure decreases by up to 4 mm Hg, whichdistends the
right atrium, allowing for faster filling from the vena cava, increasing
ventricular preload, and increasing the stroke volume. Conversely
during expiration, the heart iscompressed, decreasing cardiac
efficiency and reducing stroke volume. However, the overallnet effect
of respiration is to act as pump for the cardiovascular system. When
the frequencyand depth of respiration increases, the venous return
increases, leading to increased cardiacoutput.
Figure 3.2 Photoplesmography of respiration
3.3.3 Monitoring Depth of Anesthesia
Anesthesiologist must often judge subjectively whether a patient is
sufficiently anesthetizedfor surgery. As seen in the figure if a patient
is not sufficiently anesthetized the sympatheticnervous system
response to an incision can generate an immediate response in the
amplitudeof thePPG.
10. Figure 3.3 Photoplesmography under the anesthesia condition
3.3.4 Monitoring Hypo and Hypervolemia
Shamir, Eidelman, et al. studied the interaction between
inspiration and removal of 10% of a patient¶s blood volume for blood
banking before surgery. They found that blood loss could bedetected both
from the photoplethysmogram from a pulse oximeter and an arterial
catheter.Patients showed a decrease in the cardiac pulse amplitude
caused by reduced cardiac preloadduring exhalation when the heart is being
compressed.
11. Chapter 4
Study Description and Experimental Setup
4.1Experimental setup
Figure 4.1 Experimental setup
Abasic webcamembeddedina laptop(built-iniSight camera ona MacbookPro
by AppleInc.) was used to record the videos for analysis. All videos
were recorded in color (24-bitRGB with 3 channels × 8 bits/channel)
at 15 frames per second (fps) with pixel resolution of 640 × 480 and
saved in AVI format on the laptop. 12 participants (10 males, 2
females) between the ages of 18-31 years were enrolled for this study
that was approved by theMassachusetts Institute of Technology
Committee On the Use of Humans as ExperimentalSubjects
(COUHES). The sample featured participants of both genders,
different ages andwith varying skin colors (Asians, Africans and
Caucasians). Informed consent was obtainedfrom all the participants
prior to the start of each study session.
12. Figure 4.2 Bloodvolumepulsesensor
For all experiments, an FDA-approved and commercially available
blood volume pulse (BVP) sensor [6] (Flexcomp Infiniti by Thought
Technologies Ltd.) was used tomeasure the participant¶s BVP signal
via a finger probe at 256 Hz for validation. Theexperiments were
conducted indoors and with a varying amount of sunlight as the
onlysource of illumination. Figure 1 show the experimental setup.
Participants were seated at atable in front of a laptop at a distance of
approximately 0.5 m from the built-in webcam. Twovideos, each
lasting one minute, were recorded for all participants. During the first
videorecording, participants were asked to sit still and stare at the
webcam. For the second videorecording, participants were asked to
move naturally as if they were interacting with thelaptop, but to avoid
largeorrapid motionsandto keep the hand wearing the fingerBVPsensor still.
In addition, single, one-minute video of three participants sitting
together at restwas recorded.
13. 4.2PulseMeasurement Methodology
Figure 4.3 Figure showing the pulse measurement methodology
results
Post processing and analysis of both the video and physiological
recordings were done usingcustom software written in
MATLAB (The MathWorks, Inc.). First, an automated facetracker
was used to detect faces within the video frames and localize the
measurement regionof interest (ROI) for each video frame. A free
MATLAB-compatible version of the OpenComputer Vision (OpenCV)
library was used to obtain the cordinates of the face location.The OpenCV face
detection algorithm is based on work by Viola and Jones, as well asLienhart
and Maydt .A cascade of boosted classifier uses 14 Haar-like digital
image featurestrained with positive and negative examples. The pre
trained frontal face classifier availablewith OpenCV 2.0 was used.
The cascade nature uses a set of simple classifiers that areapplied to
each area of interest sequentially. At each stage a classifier is built
using aweighted vote, known as boosting.Either all stages are passed,
meaning the region is likely to contain a face, or the areais rejected.
The dimensions of the area of interest are changed sequentially in
order to identify positive matches of different sizes. For each face
detected, the algorithm returns the x- and y-coordinates along with the
14. height and width that define a box around the face. From thisoutput,
the centre 60% width and full height of the box was selected as the
ROI for subsequent calculations. To prevent face segmentation errors
[7] from affecting the performance of our algorithm, the face
coordinates from the previous frame were used if nofaces were detected.
Ifmultiplefacesweredetected whenonlyone wasexpected,thenour algorithm
selected the face coordinates that were the closest to the coordinates
from the previous frame.
The ROI was then separated into the three RGB channels and
spatially averaged over all pixels in the ROI to yield a red, blue and
green measurement point for eachframe andform the raw traces
X1(t),x2(t) and x3(t) respectively.. Subsequent processing
was performed using a 30 s moving window with 96.7% overlap (1 s
increment). The raw RGBtraces are normalized as follows:
𝑥( 𝑡) −
𝑋𝑖(𝑡)𝜇𝑖
𝜎𝑖
for each i =1,2,3 where i, 𝜇 and 𝜎 are the mean and standard deviation
of xi(t) respectively. The normalization transforms xi(t) to xi’(t)
which iszero-mean and hasunit variance.
4.3Mean
Mean is where you add up all the numbers and divide it by the
amount of numbers therewere. There are other statistical measures
that use samples that some people confuse withaverages - including
'median' and 'mode'. Other simple statistical analyses use measures
of spread, such as range, inter quartile range, or standard deviation.
For a real-valued randomvariable X , the mean is the expectation of X .
For a data set, the mean is the sum of the valuesdivided by the number
of values. The mean of a set of numbers x1, x2, ..., xn is
typicallydenoted by , pronounced " x bar". This mean is a type of
arithmetic mean. If the data set was based on a series of observations
obtained by sampling a statistical population, this mean istermed the
"sample mean" to distinguish it from the "population mean".The mean of an
image is the mean values of gray level values of all its pixels. The mean
isgiven by theformulae
15. 𝑢 = (𝑟 ∗ 𝑐)−1 ∑ ∑ 𝐹(𝑖, 𝑗)
𝑐
𝑗=1
𝑟
𝑖=1
Where, u=mean
F(i,j)=the image frame
r =number ofrowsofthe image
c=number ofcolumnsofthe image
4.4Standard Deviation
Standard deviation is a widely used measurement of variability or
diversity used in statisticsand probability theory. It shows how much
variation or "dispersion" there is from the"average" (mean, or
expected/budgeted value). A low standard deviation indicates that
thedata points tend to be very close to the mean, whereas high
standard deviation indicates thatthe data are spread out over a large
range of values.Technically, the standard deviation of a statistical
population, data set, or probabilitydistribution is the square root of
its variance. It is algebraically simpler though practically lessrobust
than the average absolute deviation. A useful property of standard
deviation is that,unlike variance, it is expressed in the same units as
the data. Note, however, that for measurements with percentage as
unit, the standard deviation will have percentage points asunit.
The standard deviation of a 2-D image is calculated for all the pixel values of
theimage. It is given by the formulae
𝜎 = √(𝑟 ∗ 𝑐)−1 ∑ ∑(𝐹( 𝑖, 𝑗) − 𝑢)2
𝑐
𝑗=1
𝑟
𝑖=1
Where, 𝜎 =standard deviation
u=mean valueoftheimage.
F (i,j)=the image frame.
r =number ofrowsofthe image.
c=number ofcolumnsofthe image.
16. Chapter 5Blind Signal Separation and FFT
5.1Blind Source Separation
The technique used for noise removal from physiological signals is
blind source separation(BSS) [8]. Typically, the observations are
acquired from the output of a set of sensors, whereeach sensor
receives a different combination of the source signals.Blind signal
separation, also known as blind source separation, is the separation of
aset of signals from a set of mixed signals, without the aid of
information (or with very littleinformation) about the source signals
or the mixing process. Blind signal separation relies onthe assumption
that the source signals do not correlate with each other. For example, thesignals
may be mutually statistically independent or decorrelated. Blind
signal separation thusseparates a set of signals into a set of other
signals, such that the regularity of each resultingsignal is maximized,
and the regularity between the signals is minimized i.e.
statisticalindependence is maximized. Because temporal redundancies
(statistical regularities in thetime domain) are "clumped" in this way
into the resulting signals, the resulting signals can bemore effectively
deconvolved than the original signals.There are different methods of
blind signal separation:
Principal components analysis
Singular value decomposition
Independent component analysis
Dependent component analysis
Non-negative matrix factorization
Low-Complexity Coding and Decoding
Stationary Subspace Analysis
Here wewillfocusonBSS by Independent Component Analysis
The normalized raw traces are then decomposed into three
independent source signalsusing ICA [9]. In this report, we used the
joint approximate diagonalization of eigen matrices(JADE) algorithm
developed by Cardoso. This approach by tensorial methods uses fourth-order
cumulant tensors and involves the joint diagonalization of cumulant
matrices; thesolution of this approximates statistical independence of the
sources (to the fourth order).Although there is no ordering of the ICA
components, the second component typicallycontained a strong
17. plethysmographic signal. For the sake of simplicity and automation,
thesecond component was selected as the desired source signal.
5.2Independent Component Analysis
Independent component analysis (ICA) is a computational method for
separating amultivariate signal into additive subcomponents
supposing the mutual statisticalindependence of the non-Gaussian
source signals. It is a special case of blind sourceseparation.
When the independence assumption is correct, blind ICA
separation of a mixed signalgives very good results. It is also used for
signals that are not supposed to be generated by amixing for analysis
purposes. A simple application of ICA is the ³cocktail party
problem´,where the underlying speech signals are separated from a
sample data consisting of peopletalking simultaneously in a room.
Usually the problem is simplified by assuming no timedelays or
echoes. An important note to consider is that if N sources are present,
at least N observations (e.g. microphones) are needed to get the
original signals. This constitutes thesquare ( J = D, where D is the
input dimension of the data and J is the dimension of themodel). Other
cases of underdetermined ( J < D) and over determined ( J > D) have
beeninvestigated.ICA finds the independent components (aka factors,
latent variables or sources) bymaximizing the statistical independence
of the estimated components. We may choose one of many ways to
define independence, and this choice governs the form of the ICA
algorithms.The two broadest definitions of independence for ICA are
1) Minimization of Mutual Information
2) Maximization of non-Gaussianity
18. The Non-Gaussianity family of ICA algorithms, motivated by the
central limittheorem, uses kurtosis and negentropy. The
Minimization-of-Mutual information (MMI)family of ICA algorithms
uses measures like Kullback-Leibler Divergence and maximum-
entropy. Typical algorithms for ICA use centering, whitening (usually
with the eigenvaluedecomposition), and dimensionality reduction as
preprocessing steps in order to simplify andreduce the complexity of
the problem for the actual iterative algorithm. Whitening
anddimension reduction can be achieved with principal
component analysis orsingular valuedecomposition. Whitening
ensures that all dimensions are treated equally a priori before
thealgorithm is run. Algorithms for ICA include infomax, FastICA,
and JADE, but there aremany others also. In general, ICA cannot
identify the actual number of source signals, auniquely correct
ordering of the source signals, nor the proper scaling (including sign)
of thesource signals. ICA is important to blind signal separation and
has many practicalapplications. It is closely related to (or even a
special case of) the search for a factorial codeof the data, i.e., a new
vector-valued representation of each data vector such that it getsuniquely
encoded by the resulting code vector (loss-free coding), but the code
componentsare statistically independent.
5.2.1 Mathematical Definitions
Linear independent component analysis can be divided into noiseless
and noisy cases, wherenoiseless ICA is a special case of noisy ICA.
Nonlinear ICA shouldbe considered as aseparate case.
The data is represented by the random vector x=(x1,... ...,xm)
and the componentsas the random vector s=(s1,... ...,sm). The task isto
transformthe observed data , usingalinear static transformation
W as s=Wx, into maximally independent components
S measured by some function F (s1,... ...,sm) ofindependence.
Linear Noiseless ICA
The components
20. weighted by themixing weights
.
Linear Noisy ICA
With the added assumption of zero-mean and uncorrelated Gaussian
noisen, the ICA modeltakes the form
x=As+n
Identifiability
The independent components are identifiable up to a permutation and scaling of
the sources.This identifiability [10] requires that:
At mostoneofthe sources is Gaussian,
‡ The number of observed mixtures m, must be at least as large as the number
ofestimated componentsn::m>=n. It is equivalent to say that the
mixing matrix A must be offullrank foritsinverse toexist.
In this study, the underlying source signal of interest is the
cardiovascular pulse wavethat propagates throughout the body.
Volumetric changes in the facial blood vessels duringthe cardiac cycle
modify the path length of the incident ambient light such that
thesubsequent changes in amount of reflected light indicate the timing
of cardiovascular events.By recording a video of the facial region
with a webcam, the RGB color sensors pick up amixture of the
reflected plethysmographic signal along with other sources of
fluctuations inlight due to artifacts such as motion and changes in ambient
lighting conditions. Given thathemoglobin absorptivity differs across the
visible and near-infrared spectral range, eachcolor sensor records
a mixture of the original source signals with slightly different
weights.These observed signals from the red, green and blue color
sensors are denoted by (t ), (t ) and (t ) respectively,
which are amplitudes of the recorded signals (averages of all pixels in
the facial region) at time pointt . In conventional ICA the number of
recoverablesources cannot exceed the number of observations, thus we
assumed three underlying sourcesignals, represented by
21. (t ), (t )and (t ). The ICA model assumes that the
observedsignals are linear mixtures of the sources, i.e.
foreach i =1,2,3
This can be represented compactly by the mixing equation
x(t )= As(t )
The column vectors
,
and thesquare 3 × 3 matrixA contains the
mixture coefficientsija. The aim of ICA is to find aseparating ordemixing
matrix that is an approximation of the inverse of the originalmixing matrixA
whose output
sÖ(t )=Wx(t )
is an estimate of the vector s(t ) containing the underlying source signals.
According to thecentral limit theorem [11], a sum of independent
random variables is more Gaussian than theoriginal variables. Thus,
to uncover the independent sources,Wmust maximize the non-Gaussianity
of each source. In practice, iterative methods are used to maximize or minimize
agiven cost function that measures non-Gaussianity such as kurtosis,
negentropy or mutualinformation.
finally we applied the fast Fourier transform (FFT) on the
selected source signal toobtain the power spectrum. The pulse
frequency was designated as the frequency thatcorresponded to the
highest power of the spectrum within an operational frequency
band.We set the operational range to [0.75, 4] Hz (corresponding to [45, 240]
bpm) to provide awide range of heart rate measurements. Similarly, we
obtained the reference heart ratemeasurements from the recorded
finger BVP signal.
5.3 FFT
A fast Fourier transform (FFT) is an efficient algorithm to compute
the discrete Fourier transform (DFT) and its inverse. There are many
distinct FFT algorithms involving a widerange of mathematics, from
simple complex-number arithmetic to group theory and
number theory. A DFT decomposes a sequence of values into
components of different frequencies This operation is useful in many
fields (see discrete Fourier transform for properties andapplications of
the transform) but computing it directly from the definition is often
22. too slowto be practical. An FFT is a way to compute the same result
more quickly.
Computing a DFT of N points in the naive way, using the
definition, takes O( )arithmetical operations, while an FFT can
compute the same result in only O( N log N )operations. The
difference in speed can be substantial, especially for long data sets
where N may be in the thousands or millions²in practice, the
computation time can be reduced byseveral orders of magnitude in
such cases, and the improvement is roughly proportional
to N /log( N ). This huge improvement made many DFT-based
algorithms practical; FFTs are of great importance to a wide variety of
applications, from digital signal processing and solving partial
differential equations to algorithms for quick multiplication of large
integers.
The most well known FFT algorithms depend upon the
factorization of N , but(contrary to popular misconception) there are
FFTs with O( N log N ) complexity for all N ,even for prime N . Many
FFT algorithms only depend on the fact that is at the primitive rootof
unity, and thus can be applied to analogous transforms over any finite field,
suchasnumber-theoretic transforms. Since the inverse DFT is the same
as the DFT, but with theoppositesign in the exponent and a1/ N factor, any
FFT algorithm can easily be adapted for it.An FFT computes the DFT
and produces exactly the same result as evaluating the DFTdefinition
directly; the only difference is that an FFT is much faster. (In the
presence of round-off error, many FFT algorithms are also much more
accurate than evaluating the DFTdefinition directly, as discussed
below.) Let x0, ...., x N -1 be complex numbers. The DFT isdefined by the
formula
23. Evaluating this definition directly requiresO( ) operations,
there are N outputs Xk ,and each output requires a sum of N terms. An
FFT is any method to compute the sameresults in O( N log N )
operations. More precisely, all known FFT algorithms require
( N log N ) operations (technically,O only denotes an upper bound),
although there is no proof that better complexity is impossible. To
illustrate the savings of an FFT, consider the count of complex
multiplications and additions. Evaluating the DFT's sums directly
involves N 2complex multiplications and N ( N í 1) complex additions
[of whichO( N ) operations can besaved by eliminating trivial operations
such as multiplications by 1. The well-known radix-2Cooley±Tukey
algorithm, for N a power of 2, can compute the same result with
only( N /2)log2 N complex multiplies (again, ignoring simplifications of
multiplications by 1 andsimilar) andN log2 N complex additions. In
practice, actual performance on moderncomputers is usually
dominated by factors other than arithmetic and is a complicated
subject, buttheoverallimprovement from ( N 2)to (N logN ) remains.
5.4Threshold BPMSelection
Despite the application of ICA in our proposed methodology, the
pulse frequencycomputation may occasionally be affected by noise
[12]. To address this issue, we utilize thehistorical estimations of the
pulse frequency to reject artifacts by fixing a threshold for maximum
change in pulse rate between successive measurements (taken 1 s
apart). If thedifference between the current pulse rate estimation and
the last computed value exceeded thethreshold (we used a threshold
of 12 bpm in our experiments), the algorithm rejected it andsearched
the operational frequency range for the frequency corresponding to
the next highest power that met this constraint. If no frequency peaks
that met the criteria were located, thenthe algorithm retained the
current pulse frequency estimation.
26. Figure 6.7
Mirrorshowing the heartbeat oftheperson
Conclusions and Future Scope
This concept describes a novel methodology for recovering the
cardiac pulse rate from videorecordings of the human face and
implementation using a simple webcam with ambientdaylight
providing illumination. This is the first demonstration of a low-cost
method for non-contact heart rate measurements that is automated and
motion-tolerant. Moreover, thisapproach is easily scalable for
simultaneous assessment of multiple people in front of acamera.
Given the low cost and widespread availability of webcams, this
technology is promising for extending and improving access to
medical care.
Although this concept only addressed the recovery of the
cardiac pulse rate, manyother important physiological parameters
such as respiratory rate, heart rate variability andarterial blood oxygen
saturation can potentially be estimated using the proposed
technique.Creating a real-time, multi parameter physiological
measurement platform based on thistechnologywill be the subject of future
work.