JK-TK/GRADE-8-TERM-2 huggingface dataset:
The most common ones are:8.1 Line Printers IBM 1403 line printer Example: Printronix P7-1500N line matrix printer As the name suggests, Line printers print one line of text at a time the full width of the page . They use a continuous feed of paper instead of individual cut sheets. And they can print up to 2,500 lines per minute. Pros High-speed printing More durable Low operating costs Consumables are less harmful to the environment Cons Low print quality and cannot print graphics Very noisy, requires sound-absorbing cases 8.2 Dot Matrix Printers Epson LX310 Example: Tvs MSP 250 In a dot matrix printer, the pins are arranged in one or multiple vertical columns. The print head which contains several pins moves up and down or in a back and forth motion and prints by striking an ink-soaked cloth ribbon against the page. This is just like a typewriter, but it can also print arbitrary patterns and not just particular characters. A character printed by a dot matrix printer is actually an accumulation of multiple dots on a very small region of the paper. The printer can be used for text, multiple fonts, and basic graphical printing. The outputs, however, have a dotted appearance. Pros Low printing cost Reliable Prints on multipart forms or carbon copies Useful for data logging Cons Slow speed Limited print quality They can be used to print multiple copies at the same time with the help of carbon copying. Thus, they are widely installed in offices and shops where multipart forms are required. 8.3 Daisy Wheel Printers The daisy wheel and print head on a Diablo D-25 printerExample: Commodore DPS 1101 A daisy wheel printer contains a disk and attached extension on which molded metal characters are mounted. When printing, the printer rotates the disk to each character and strikes it into an ink ribbon to create characters on paper. Pros Can use heavy paper grades and fan-fold paper Can create carbon copies Low costs and maintenance Cons Slow speed Low print quality 7. Minilab Printers SureLab D870Example: Epson Sure Lab D1070DE Minilabs are small photographic-developing and printing systems that are used in several retail stores to provide quick photo finishing services.
When printing, the printer rotates the disk to each character and strikes it into an ink ribbon to create characters on paper. Pros Can use heavy paper grades and fan-fold paper Can create carbon copies Low costs and maintenance Cons Slow speed Low print quality 7. Minilab Printers SureLab D870Example: Epson Sure Lab D1070DE Minilabs are small photographic-developing and printing systems that are used in several retail stores to provide quick photo finishing services. A minilab machine is made of two systems: a film processor and a printer paper processor . Pros Perfect for photo processing High-capacity ink packs Prints on double- or single-sided sheet media Provides better exposed, color-corrected prints in less than 30 minutes Cons Quite pricey Larger and bulkier and than typical printers The Agfa and Kodak minilab machines use C41b chemistry to process films and RA-4 chemistry to process the paper. Depending on the device capabilities and operator s expertise, films can be ready for collection within 20 minutes. 6. Thermal PrintersF2C portable thermal printer Example: Polono Label Printers A thermal printer is made of three components: Thermal head: Generates heat to produce an image on the page Platen: A roller that moves the page Spring: Holds the printhead and paper together by applying small pressure The printer passes paper with a thermochromic coating over a print head. This print head contains several electrically heated elements, typically arranged as a line of small, closely spaced dots. The coating on the paper turns black in the region where it is heated, generating an image. These printers can have a resolution of up to 1,200 DPI. Although most of them print black and white monochrome text, some produce twocolor images. Due to decent print quality, speed, and portability, thermal printers are widely used in the banking, retail, grocery, healthcare, and airline industries. Voucher printers in slot machines, information kiosks, and point of sale systems are some of the commercial applications of these printers.
Although most of them print black and white monochrome text, some produce twocolor images. Due to decent print quality, speed, and portability, thermal printers are widely used in the banking, retail, grocery, healthcare, and airline industries. Voucher printers in slot machines, information kiosks, and point of sale systems are some of the commercial applications of these printers. Pros More quiet and faster than dot matrix printers Easier to use as there is less use of software involved Requires less maintenance Comes in various models and sizes Cons Prints fewer colors The high heat limits wax and resin choices They are also used to generate sub-seafloor seismic imagery and print real-time records of side-scan sonar. In the data processing field, they are used for quickly creating hard copies of continuous hydrographic or seismic records. 5. Dye-sublimation PrintersTexart RT-640 Example: Texart XT-640 High-Volume Dye-Sublimation Printer Dye-sublimation printers utilize heat to transfer dye onto materials like card, paper, fabric, or plastic. They use the CMYO cyan, magenta, yellow, over coating system to deposit the ink on the surface one color at a time. The ink is deposited via a heat press, which ultimately changes from solid to gas hence the name sublimation and enters the material. The process is carried out at lower temperatures and higher pressures. Small heating elements on the print head change temperatures quickly to lay different amounts of dye. Polyester and polyester resin-coated substances are the perfect materials for this printing technique. Pros Allows printing on rigid surfaces Print thousands of colors using four-color ink CMYK Best for creating ID cards and photographic prints Short learning curveCons The item may lose color over the months Specific type of ink is required Professional and consumer dye-sublimation printers are developed for creating photographic prints, ID cards, license plates, etc. And since these printers are available in various sizes and styles, consumers can print on various products like mouse pads, coffee mugs, handbags, smartphone cases, dresses, pillows, and more. 4. Solid Ink Printers Example: HP Laserjet M209DW As the name suggests, these printers use solid ink instead of fluid ink or toner powder.
And since these printers are available in various sizes and styles, consumers can print on various products like mouse pads, coffee mugs, handbags, smartphone cases, dresses, pillows, and more. 4. Solid Ink Printers Example: HP Laserjet M209DW As the name suggests, these printers use solid ink instead of fluid ink or toner powder. The printer melts the ink which is usually a waxy resinbased polymer to print images on paper or any substrate. This is how the process goes: small pucks or spheres of solid ink are stored in a hopper. From there, they are transferred to the printhead and melted as per the requirement. Pros Provides precise prints with bright colors Can print on many different types of media Less waste generated compared to inkjet or laser printers Suitable for intermittent use with long periods of downtime Cons The printer need to pause and reheat in between prints Ink may clog printhead nozzles This type of printer can create large graphic images with bright and vivid colors at reasonable costs. It is suitable for users who always have to print in color and require high-quality images. And since the solid ink doesn t dry out over time, you don t have to order new cartridges when you need to print something after a long time. 3. 3D PrintersPrusa I3 MK3S Example: Tronxy X5SA Pro 3D printers are based on a technique called additive manufacturing. They create a physical three-dimensional object from a CAD computeraided design or digital model. It involves adding materials such as powder grains or composites or bio-materials layer by layer at the millimeter scale. Unlike injection molding and CNC machining that uses various cutting tools to make objects, 3D printers require no cutting tools. They construct objects directly onto the built platform. Pros Enables fast design and production Gives you the flexibility to create anything that fits within its build volume Minimize waste Cost-effective Cons Not yet versatile enough to work with most materials Requires post processing Depending on the type of printer, material used, and size of the object, a print takes several hours to complete. The finished object often requires post-processing like sanding, paint, or other conventional finishing touches to achieve the desired surface finish. 3D printing processes can be categorized into 7 groups: 1. Vat photo polymerization 2.
The finished object often requires post-processing like sanding, paint, or other conventional finishing touches to achieve the desired surface finish. 3D printing processes can be categorized into 7 groups: 1. Vat photo polymerization 2. Material Extrusion 3. Sheet Lamination 4. Directed Energy Deposition 5. Material Jetting 6. Binder Jetting 7. Powder Bed Fusion Modern 3D printers are advanced enough to create complex structures and geometries that would be otherwise impossible to build manually. They can be used to build a range of objects, from simple prototypes to intricate final products, such as medical instruments, aircraft parts, ecofriendly buildings, and even artificial organs using layers of human cells. 2. Liquid Inkjet PrintersHP Smart Tank 530 Example: Canon PIXMA G3260 The inkjet printer creates an image by propelling droplets of ink onto paper or plastic substrates. Its print head moves back and forth as the paper feeds through rollers. The complete image is made of thousands of minuscule dots, like the pixels on a television screen. These dots are extremely small between 50 and 70 microns in diameter and positioned very precisely with resolutions up to 1200 x 1440 DPI. Also, these dots can have multiple colors combined together to produce high-quality pictures. Pros Quieter than impact printers Practically no warm uptime Really good at producing natural shades and colors Easy to set up and use Cons Liquid ink can dry out when stored for a longer period of time Expensive ink refillsLiquid inkjet printers perform best on nonporous paper and slightly heavy bond paper with a hard surface that effectively prevents colors from bleeding. They are available in many different varieties and sizes, ranging from small cost-efficient consumer models to expensive professional machines. While most home inkjet printers are lightweight and have low per-page costs, commercial machines are larger and print on a broader range of materials. 1. Laser Printers Pantum M6602NW Example: HP OfficeJet 5255 Laser printers have become a common consumer product, often used along with personal computers. Their working principle involves electrophotographic, which is the same technique used in photocopy machines. To create a high-quality image, the laser printer continuously passes a laser beam back and forth over a photoreceptor drum. This drum is nothing but a negatively charged cylinder.
Their working principle involves electrophotographic, which is the same technique used in photocopy machines. To create a high-quality image, the laser printer continuously passes a laser beam back and forth over a photoreceptor drum. This drum is nothing but a negatively charged cylinder. It collects positively chargedpowdered ink toner and transmits the image to paper. The paper is then slightly heated to permanently fuse the image onto it. The standard resolution in most laser printers is 600 DPI, whereas the high-end production machine can have a resolution of 2,400 DPI. Plus, they can print at a much faster rate than inkjet printers. A high-end model can print about 12,000 monochrome pages per hour or 6,000 colored pages per hour. However, they don t print color photos as well as inkjet printers do. That s why most photographers and designers prefer inkjet printers for gallery-quality photos. Pros Fast printing speed Noiseless Produces high-quality monochrome prints Mechanical components are reliable and durable Cons High initial investment cost Not suitable for high quality graphics Laser printers are well suited for office use due to their capability to quickly print large amounts of documents. Overall, they are excellent for text, documents, and printing medium-quality color photos1.1 LED Printers OKI MC853dn Example: Xerox VersaLink C7000DN LED light-emitting diode printers are generally grouped with laser printers because they use a similar technique for creating text or graphics. Both use a toner, drum, and fuser to provide high-quality prints. However, LED printers have an array of light-emitting diodes instead of a laser and mirror. Since LED printers contain fewer moving parts, they are more reliable and efficient than traditional laser printers. Plus, they are cheaper to manufacture and less prone to mechanical wear. Pros Contains fewer moving parts Inexpensive and reliable Noiseless Provides excellent image quality Cons High initial cost Slower printing speed than laser printersFactors to consider when selecting a printer Choosing the best printer can be overwhelming with so many options. To help you decide which type of new printer you should buy, consider the following factors and your specific needs: Printing Purpose Home Use: If you need a printer primarily for occasional home use, like printing documents, school assignments, or family photos, an inkjet printer should suffice.
Plus, they are cheaper to manufacture and less prone to mechanical wear. Pros Contains fewer moving parts Inexpensive and reliable Noiseless Provides excellent image quality Cons High initial cost Slower printing speed than laser printersFactors to consider when selecting a printer Choosing the best printer can be overwhelming with so many options. To help you decide which type of new printer you should buy, consider the following factors and your specific needs: Printing Purpose Home Use: If you need a printer primarily for occasional home use, like printing documents, school assignments, or family photos, an inkjet printer should suffice. They re affordable and can handle a variety of printing tasks. Small Businesses: A laser printer is a good choice for a small office or home office SOHO where you must print frequently. It offers fast and efficient text printing. Color or Black and White Consider an inkjet or color laser printer if you need to print in color. For basic black-andwhite documents, a monochrome laser printer is cost-effective. Print Volume For bulk printing, a laser printer with a high page-per-minute PPM rate and a large paper tray may be more suitable. Inkjet printers make a better choice for lower print volumes. Printing Photos If you re into photography and want to print photos, a dedicated photo printer or a highquality color inkjet printer with photo capabilities is a good choice. Consider other costs like glossy photo paper for the printing process, maintenance, etc. Size and Space Consider the available space where you plan to put the printer. Consider a compact inkjet printer if you have a small space, as laser printers can be larger. All-in-One or Single Function An all-in-one a multifunction printer combines printing, copying, scanning, and even faxing in one machine. It s convenient for saving space and money if you need these functions. Connectivity Options Ensure the printer you choose has the connectivity options you need. Common features include USB, Wi-Fi, Bluetooth, and mobile printing capabilities. Cost Considerations Think about both the upfront cost of the printer and the long-term cost of consumables like ink or toner cartridges. Some printers may be inexpensive initially but cost more to maintain. Brand and Model Consider reputable brands known for quality and reliability. Read reviews and compare printer models within your budget. Additional Features Some printers have extra features like automatic duplex double-sided printing, touchscreen controls, and memory card slots for direct photo printing.
Brand and Model Consider reputable brands known for quality and reliability. Read reviews and compare printer models within your budget. Additional Features Some printers have extra features like automatic duplex double-sided printing, touchscreen controls, and memory card slots for direct photo printing. Assess whether these features matter to you. Compatibility Ensure the printer is compatible with your computer s operating system. Most modern printers support Windows and macOS, but it s always good to check. Warranty and Support Check the warranty, warranty extensions, and available customer support for the printer. Extremely reliable customer service can be crucial if you encounter any issues. Environmental Considerations If you re eco-conscious, look for printers with energy-saving features, recyclable ink or toner cartridges, and eco-friendly certifications. In summary, the type of printer you should buy depends on your specific needs and budget. Consider your printing volume, fast print speeds, whether you need color printing, available space, and any extra features for high-quality prints you require. It s also a good idea to read reviews and compare prices before deciding. Considering these factors, you can find a printer that suits your print jobs and helps you achieve your printing goals efficiently. How to Print a Document from Your Computer 1 Make sure that your printer is connected and turned on. If your printer connects over Wi-Fi, this will mean making sure that you're on the same Internet network as your printer; otherwise, you'll need to plug your printer's USB cable into your computer. Check your printer's manual to confirm how to set it up if you haven't already done so. Be sure to update your printer drivers. 2 Open the document you want to print. This could be a PDF, Word document, Excel spreadsheet, or even photos. Use the File Explorer to find the file if needed. 3 On your keyboard, press Ctrl P . This is the keyboard shortcut to open the print menu. You can also manually open the print menu by clicking the printer icon. In some apps, you'll need to click File and then Print. The print menu may look different depending on the application used to open your file. 4 Select your printer. Click the "Printer" drop-down box, then click your printer's name. If you don't see your printer, you'll need to add it. 5 Select a number of copies. In the "Copies" box, type in the number of copies of the document that you'd like to print.
First we ll tell you what RAM memory alternatively referred to as main memory, primary memory, or system memory, Random Access Memory RAM in a computer system, it is also sometimes known as read-write memory or RWM, then we ll go over how RAM works in Macintosh s and pcs. Also, there are different kinds of RAM, including VRAM, PRAM, DRAM and SRAM . Random access memory RAM This is the most common type of main memory. It is called random access memory RAM because ; its content can be read directlyregardless of the sequence in which it was stored. As opposed to ROM, the content in RAM is held temporarily and its content is lost once the computer is turned off. Characteristics of random access memory RAM are: 1.Data can be read retrieved and written stored in it. 2 .RAM is a temporary volatile storage because its content disappears when the computer is switched off. 3.Its content is user defined i.e. the user dictates what is to be contained in the RAM. Types of RAM There are two types of-RAM namely, static RAM SRAM and dynamic DRAM .Static RAM is very fast compared to dynamic RAM and holds its content as long as there is power. Dynamic RAM on the other hand can only hold its content for a short while even when power is all .To maintain the content of dynamic RAM, the memory chip is designed in away that its content is refreshed automatically rewritten severally per second. Static RAM is more expensive. It is mostly used to make special types of memories. Special purpose memories Apart from ROM and RAM there are several types of special purpose memories found inside the CPU or in the input and output devices. These memories are vital because they increase the overall performance of data and instructions moving in and out of the CPU. These memories include buffers, registers and cache memory. Buffers This is a temporary holding place that may be part of the CPU or built in an input or output device. Because the CPU is very fast compared to the input or output devices, buffers provide temporary storage so that the CPU is set free to carry out other activities instead of waiting for all data to be entered or information to be output. For example since a printer cannot work at the speed of a CPU, the printer buffers temporarily holds the output to be printed hence freeing the CPU to perform other functions. Buffers can hold more than one piece of data at a time.
GRADE 8 RATIONALIZED AGRICULTURE AND NUTRITION LESSON NOTESSTRAND 1-CONSERVING AGRICULTURAL ENVIRONMENT1.1 -Soil Conservation Measures. Soil conservation measures refers to a combination of practices done or taken to prevent the loss of soil through soil erosion. Reasons Importance for Soil conservation. To keep top soil in its place. To maintain fertility in the soil. To maintain soil productivity. Helps to increase agricultural production promotes food security. Methods of soil conservation in agricultural environment. Strip cropping. Grassed water ways. Stone lines. Trash lines. Soil bunds. A. Strip cropping. It is the growing of crops in a way that crops that have little soil cover like maize are grown in alternating strips with those that have good ground cover such as sweet potatoes. Permanent vegetation such as grass can also be used as strips. The role of strip crop is it prevents loss of soil through surface runoff. B. Grassed water ways. Grassed waterways are natural or man-made shallow channels in which excess rain water flows. Grass and other vegetations are planted to grow in the channels. When surface run off is directed in the channels, the vegetation in the channels lower the speed of run off and also traps eroded soil. C. Stone lines. These are stones of different sizes heaped in a line along the contour to prevent loss of soil down the slope through run off. Stone lines reduce speed of run off increasing water infiltration especially in semi-arid areas. Water infiltration is the downward entry of water into the soil from the surface. Stone lines are suitable in gently slopes. D. Trash lines. Trash lines are plant materials or crop residues remains arranged along the contour in a cultivated field. Trash lines help to reduce runoff hence preventing loss of soil from land. They also increase water infiltration into the soil. Trash line should be 1 m wide and 0.5 m high. E. Soil bunds. A bund refers to a heap of compacted soil made along the contours. Grasses can be grown on top of the bunds to hold soil together firmly. Bunds help to reduce the volume of water flowing downwards in a cultivated field after rain fall. Bunds enhance water infiltration. NOTE:Most structures constructed to conserve the soil are made along the contour line. Therefore, it is very important to establish the contour lines first before construction of the structures.