A CD-ROM can store up to 783MB of data through a series of microscopic bumps imprinted in a spiral track on the disc from the inside to outside. A laser and optical system precisely reads the bumps, which reflect light differently than the spaces between bumps. This allows the reader to interpret the bits of data on the CD as it spins and the laser moves from the center to the outer edge of the disc.
1) The document summarizes a presentation on co-simulating plug-in electric vehicle (PEV) coordination schemes over a fiber-wireless (FiWi) smart grid communications infrastructure.
2) Simulation results showed that uncoordinated PEV charging can cause critical voltage fluctuations as penetration levels increase, while coordinated schemes using a proactive algorithm distributed the load better.
3) A reactive control algorithm was also proposed to quickly unplug PEVs and solve critical voltage fluctuations detected by sensors communicating with a distribution management system over the FiWi network.
Steven Sasson invented the first digital camera in 1975 at Kodak using a charge-coupled device image sensor. A digital camera encodes digital images digitally using an optical lens and image sensor such as CCD or CMOS that converts light into pixel values. Digital cameras come in various types including compact cameras for snapshots, bridge cameras resembling DSLRs, mirrorless cameras with interchangeable lenses, and digital single-lens reflex cameras which use a mirror to direct light through an optical viewfinder. Common file formats for digital images include JPEG, TIFF, and raw formats.
The document summarizes the history and features of digital cameras. It discusses how digital camera technology evolved from video camera technology. Early digital cameras included the Sony Mavica in 1981 and models from Apple, Kodak, and Casio in the 1990s. The document then describes the basic features, ease of use, brands, working principles including CCD/CMOS sensors and resolution, parts, advantages like immediate viewing, and disadvantages such as cost and low-light performance of digital cameras.
LCD screens use liquid crystals to control the polarization of light and display images. They consist of millions of pixels made up of red, green, and blue sub-pixels. When voltage is applied to the liquid crystals, they twist polarized light, allowing it to pass through filters and be seen by the human eye. LCD screens work by varying the intensity of the red, green, and blue sub-pixels to trick the brain into perceiving different colors, even though it only sees light of the three primary colors. LCD displays are used widely in computer monitors, televisions, and other electronics.
Electronic paper displays work like ordinary paper and use plastic substrates. They can hold static images indefinitely without using electricity. Plasma displays utilize small cells containing electrically charged gases to produce images. Speech output can include speech synthesis, which converts text to speech, or speakers and headphones. Output devices discussed include electronic paper, plasma displays, and speech synthesis technology.
A CD-ROM can store up to 783MB of data through a series of microscopic bumps imprinted in a spiral track on the disc from the inside to outside. A laser and optical system precisely reads the bumps, which reflect light differently than the spaces between bumps. This allows the reader to interpret the bits of data on the CD as it spins and the laser moves from the center to the outer edge of the disc.
1) The document summarizes a presentation on co-simulating plug-in electric vehicle (PEV) coordination schemes over a fiber-wireless (FiWi) smart grid communications infrastructure.
2) Simulation results showed that uncoordinated PEV charging can cause critical voltage fluctuations as penetration levels increase, while coordinated schemes using a proactive algorithm distributed the load better.
3) A reactive control algorithm was also proposed to quickly unplug PEVs and solve critical voltage fluctuations detected by sensors communicating with a distribution management system over the FiWi network.
Steven Sasson invented the first digital camera in 1975 at Kodak using a charge-coupled device image sensor. A digital camera encodes digital images digitally using an optical lens and image sensor such as CCD or CMOS that converts light into pixel values. Digital cameras come in various types including compact cameras for snapshots, bridge cameras resembling DSLRs, mirrorless cameras with interchangeable lenses, and digital single-lens reflex cameras which use a mirror to direct light through an optical viewfinder. Common file formats for digital images include JPEG, TIFF, and raw formats.
The document summarizes the history and features of digital cameras. It discusses how digital camera technology evolved from video camera technology. Early digital cameras included the Sony Mavica in 1981 and models from Apple, Kodak, and Casio in the 1990s. The document then describes the basic features, ease of use, brands, working principles including CCD/CMOS sensors and resolution, parts, advantages like immediate viewing, and disadvantages such as cost and low-light performance of digital cameras.
LCD screens use liquid crystals to control the polarization of light and display images. They consist of millions of pixels made up of red, green, and blue sub-pixels. When voltage is applied to the liquid crystals, they twist polarized light, allowing it to pass through filters and be seen by the human eye. LCD screens work by varying the intensity of the red, green, and blue sub-pixels to trick the brain into perceiving different colors, even though it only sees light of the three primary colors. LCD displays are used widely in computer monitors, televisions, and other electronics.
Electronic paper displays work like ordinary paper and use plastic substrates. They can hold static images indefinitely without using electricity. Plasma displays utilize small cells containing electrically charged gases to produce images. Speech output can include speech synthesis, which converts text to speech, or speakers and headphones. Output devices discussed include electronic paper, plasma displays, and speech synthesis technology.
Inkjet printing works by propelling droplets of ink onto paper or other surfaces from ink cartridges. There are two main methods - thermal inkjet uses heaters to vaporize ink and create bubbles that expel droplets, while piezoelectric inkjet uses electrical pulses to change the shape of a piezoelectric material and generate pressure to expel droplets. Inkjet printers have a housing, electronic card, printheads, and paper loading system and are commonly used for general printing though not recommended for high-quality photos.
Dot matrix printers print characters by punching ink onto paper through a print head using patterns of dots to form letters. Each character is made up of a specific map of dots, such as the letter H having 7 dots in the first column, two dots in the fourth position for the next two columns, and then 7 dots to finish. While dot matrix printers are the cheapest option for printing and are simple to build and maintain, the resolution is very low and they do not print color well.
There are four main types of touch screen technologies: capacitive, resistive, infrared grid, and optical imaging. Capacitive touch screens, made popular by Apple devices, are the most responsive and rely on changes in electrical current when a finger touches the screen. Resistive touch screens use a mesh between the screen and touch panel to register touches. Infrared grid touch screens are not common and use infrared light to detect touches. Optical imaging touch screens are new and use corner image sensors and infrared lighting to detect touch locations.
RFID scanners are devices that can interrogate RFID tags to gather information, such as recognizing credit cards or locating products around the world. They work by sending out signals that RFID tags receive and respond to with additional data, like product details and a unique identification number. While useful for retailers, RFID scanners also raise privacy issues as their long range means tags may be read without a person's knowledge and could potentially be used to track locations.
A flatbed scanner optically scans images, text, or objects and converts them into a digital image. It works by placing the item to be scanned on a glass window. The quality of a scanner is judged by its color depth, resolution in pixels per inch (ppi), and density range (Drange). Higher-end scanners have greater color depth, resolution, and Drange, allowing them to capture more detail. Potential problems include scanner noise, dust, and improper operation, which can diminish image purity. The scanned image is converted to an RGB file that can be transferred and processed on a computer.
A bar code scanner is an electronic reader that uses a light source and sensor to translate optical bar codes into electrical signals. It illuminates codes with red light, detects the reflected light with a sensor, and converts the analogue signals into digital codes that can be decoded. Retail stores commonly use bar code scanners to identify products and access online information by scanning product bar codes.
RFID uses radio waves to automatically identify objects by transferring data from tags attached to objects to an RFID reader. There are three main types of RFID tags: passive tags which have no battery and are powered by the reader's signal up to 20 feet away; semi-passive and active tags which have an internal battery allowing them to broadcast signals up to 100 feet; and types of tags differ in whether the stored data can be read, written to, or written to once only.
A touch-sensitive screen allows users to control information using their fingertips through multi-touch technology. Multi-touch screens work using mutual capacitance, which requires two layers of material - one that carries current and one that senses lines. When a user touches the screen, the touch is registered and raw data is captured and processed to remove noise and measure pressure points and touch areas to calculate exact coordinates. The signals then travel to the processor which analyzes the data to determine touch features like size, shape and location using gesture-interpretation software to determine the gesture and relay instructions to the active program. A mutual capacitance screen consists of several layers including an LCD display, glass substrate, sensing and driving lines, and a protective coating.
Impact printers physically strike paper to print, using electromagnets to move print pins that transfer ink from a ribbon to the paper. The three main types are dot matrix printers, which print one character at a time; daisy wheel printers, which rotate a character wheel; and line printers, which print an entire line at once. Barcode scanners illuminate barcodes with LEDs or lasers, use sensors to read the light reflection pattern, convert it to digital data, and decode it into text sent to a computer. Common illumination methods include single-point LEDs in wands/slots, linear LED arrays, and lasers that can scan from inches to feet away.
Inkjet printing works by propelling droplets of ink onto paper or other surfaces from ink cartridges. There are two main methods - thermal inkjet uses heaters to vaporize ink and create bubbles that expel droplets, while piezoelectric inkjet uses electrical pulses to change the shape of a piezoelectric material and generate pressure to expel droplets. Inkjet printers have a housing, electronic card, printheads, and paper loading system and are commonly used for general printing though not recommended for high-quality photos.
Dot matrix printers print characters by punching ink onto paper through a print head using patterns of dots to form letters. Each character is made up of a specific map of dots, such as the letter H having 7 dots in the first column, two dots in the fourth position for the next two columns, and then 7 dots to finish. While dot matrix printers are the cheapest option for printing and are simple to build and maintain, the resolution is very low and they do not print color well.
There are four main types of touch screen technologies: capacitive, resistive, infrared grid, and optical imaging. Capacitive touch screens, made popular by Apple devices, are the most responsive and rely on changes in electrical current when a finger touches the screen. Resistive touch screens use a mesh between the screen and touch panel to register touches. Infrared grid touch screens are not common and use infrared light to detect touches. Optical imaging touch screens are new and use corner image sensors and infrared lighting to detect touch locations.
RFID scanners are devices that can interrogate RFID tags to gather information, such as recognizing credit cards or locating products around the world. They work by sending out signals that RFID tags receive and respond to with additional data, like product details and a unique identification number. While useful for retailers, RFID scanners also raise privacy issues as their long range means tags may be read without a person's knowledge and could potentially be used to track locations.
A flatbed scanner optically scans images, text, or objects and converts them into a digital image. It works by placing the item to be scanned on a glass window. The quality of a scanner is judged by its color depth, resolution in pixels per inch (ppi), and density range (Drange). Higher-end scanners have greater color depth, resolution, and Drange, allowing them to capture more detail. Potential problems include scanner noise, dust, and improper operation, which can diminish image purity. The scanned image is converted to an RGB file that can be transferred and processed on a computer.
A bar code scanner is an electronic reader that uses a light source and sensor to translate optical bar codes into electrical signals. It illuminates codes with red light, detects the reflected light with a sensor, and converts the analogue signals into digital codes that can be decoded. Retail stores commonly use bar code scanners to identify products and access online information by scanning product bar codes.
RFID uses radio waves to automatically identify objects by transferring data from tags attached to objects to an RFID reader. There are three main types of RFID tags: passive tags which have no battery and are powered by the reader's signal up to 20 feet away; semi-passive and active tags which have an internal battery allowing them to broadcast signals up to 100 feet; and types of tags differ in whether the stored data can be read, written to, or written to once only.
A touch-sensitive screen allows users to control information using their fingertips through multi-touch technology. Multi-touch screens work using mutual capacitance, which requires two layers of material - one that carries current and one that senses lines. When a user touches the screen, the touch is registered and raw data is captured and processed to remove noise and measure pressure points and touch areas to calculate exact coordinates. The signals then travel to the processor which analyzes the data to determine touch features like size, shape and location using gesture-interpretation software to determine the gesture and relay instructions to the active program. A mutual capacitance screen consists of several layers including an LCD display, glass substrate, sensing and driving lines, and a protective coating.
Impact printers physically strike paper to print, using electromagnets to move print pins that transfer ink from a ribbon to the paper. The three main types are dot matrix printers, which print one character at a time; daisy wheel printers, which rotate a character wheel; and line printers, which print an entire line at once. Barcode scanners illuminate barcodes with LEDs or lasers, use sensors to read the light reflection pattern, convert it to digital data, and decode it into text sent to a computer. Common illumination methods include single-point LEDs in wands/slots, linear LED arrays, and lasers that can scan from inches to feet away.
2. • A USB flash drive is a data storage device that
includes flash memory with an integrated
Universal Serial Bus (USB) interface. USB flash
drives are typically removable and rewritable,
and physically much smaller than a floppy disk.
Storage capacities as large as 2 terabytes are
planned, with steady improvements in size and
price per capacity expected. Some allow up to
1,000,000 write/erase cycles, depending on the
exact type of memory chip used, and a 10 year
shelf storage time.
3. • USB flash drives are often used for the same
purposes for which floppy disks or CD-ROMs
were used, i.e. for storage, back-up and transfer
of computer files. They are smaller, faster, have
thousands of times more capacity, and are more
durable and reliable. The term drive comes
because computers read and write flash drive
data using the same system commands as for a
mechanical disk drive, with the storage appearing
to the computer operating system and user
interface as just another drive. Flash drives are
very robust mechanically.
4. 1 USB Standard-A plug
2 USB mass storage controller device
3 Test points
4 Flash memory chip
5 Crystal oscillator
6 LED
7 Write-protect switch (Optional)
8 Space for second flash memory chip