Secondary Storage

Secondary Storage Media

 Hello Guys!

Good day friends!

 

In today's lesson, we will be looking at secondary storage media. 

 

This became necessary due to the fact that primary storage devices such as RAM and ROM are limited in size and are temporary , while secondary storage is permanent and can be used for backup purposes and future use. 

 

A comparison can be made among the variety of secondary storage devices in respect to their portability, speed and capacity.

 

1.Storage capacity

Storage capacity is the amount that a particular storage medium can hold. Large capacity storage devices are more preferred for many sophisticated programs and large database.

2.Access speed

This refers to the average time needed to locate data on a secondary storage device. Access time is measured in milliseconds.

3.Portability

 This refers to the ease and accessibility of a device to transfer information from one computer to another.

For your information, every secondary storage device requires its own drive.Besides, 

Storage devices record and retrieve data, instructions and information to and from storage media. Examples are floppy disk drive, hard disk drive, compact disc drive.

Secondary storage devices fall into two main categories:

• Direct Access Storage Devices (DASD)
• Serial/Sequential Access Storage Devices (SASD)

  Storage media comprised of many types which is

• Floppy diskettes
• Hard disks
• Magnetic tape
• USB flash drive
• CD-ROM (Compact Disc Read Only Memory)
• WORM (Write Once Read Many)
• Compact Disc Recordable (CD-R)
• Compact Disc Rewritable (CD-RW)
• Digital Versatile/Video Disc (DVD)
• Flash memory

Generally,compact Disc also known as optical disc.The Holographic Versatile Disc (HVD) is an optical disc technology developed between April 2004 and mid-2008 which can store the same amount of information of between 20 and 200  Blu-ray discs. 

 

Blu-ray Disc

A red laser is used as the reference beam to read servo-information  from a regular CD-style aluminum layer near the bottom. Servoinformation is used to monitor the position of the read head over the disc, similar to the head, track, and sector information on a conventional  hard disk drive. On a CD or DVD.

How Holographic Versatile Discs (HVD) Work?

Holography is a method of recording patterns of light to produce a three-dimensional object. The recorded patterns of light are called a hologram. 

 HVD offers several advantages over traditional storage technology. First and foremost,HVDs can ultimately store more than 1 terabyte (TB) of information  that's 200 times more than a single-sided DVD and 20 times more than a current double-sided Blu-ray. 

This is partly due to HVDs storing holograms in overlapping patterns, while a DVD basically stores bits of information side-by-side. HVDs also use a thicker recording layer than DVDs an HVD stores information in almost the entire volume of the disc, instead of just a single, thin layer.

 

Volumetric recording method

DVD vs. HVD: Recording-layer depth

 

The other major boost over conventional memory systems is HVD's transfer rate of up to 1 gigabyte (GB) per second  that's 40 times faster than DVD. 

An HVD stores and retrieves an entire page of data, approximately 60,000 bits of information, in one pulse of light, while a DVD stores and retrieves one bit of data in one pulse of light.

 

 

References ;

http://www.youthlinkjamaica.com/cxc/infotech20101019.htm 

http://www.blu-ray.com/info/

http://electronics.howstuffworks.com/hvd.htm 

 

 Credit to;

Ecma International

Communications and Networks

Should you worry about Cell Phone, Cellular Antenna, and Wi-Fi Device Radiation ?

Billions of people use cell phones throughout the whole world, from the population 80% accessed to cell phone services from antenna. Wi-Fi signals for example, making business, public areas and also for home purpose has broadened is function efficiently. These numbers of users are expected to increase sharply in the next coming years, and many users are concern about potential health effect from cell phones, cellular antenna and Wi-Fi devices. Some users making a judgment by suffer rare illness have filled lawsuit against cell phones companies. Therefore, the cases usually are lost due to lack of scientific evidence towards the issue of the phone to illness.

Debates are take place in communities to discuss over placement of cellular antennas when everything breach the Act of 1996 when local government prohibit from considering health effects when making decision about cellular antenna placement.

Whatever it is, every party agree that no studies conclusively demonstrate negative health effects from cell phones, cellular antenna, and Wi-Fi devices because the technology is too new and take some time to experiment the effect.

Sources: Ethics & Issue, Shelly Cashman Series. 2011 (Text Book)

MIDI

A musical instrument digital interface (MIDI) sound card is a piece of computer hardware that allows a user to connect musical instruments and similar devices through a MIDI connector to a computer. This is typically done to use a computer to record music, especially for use in a MIDI format, and the sound card may also often act as a standard sound card as well, allowing connection of microphones, speakers, and similar devices. A MIDI sound card can potentially be built onto a computer’s motherboard, but is often a separate device installed onto the motherboard inside of the computer case.

MIDI is a standard used in a number of different industries as a way to get audio information onto a computer hard drive. This audio data can then be recorded, edited, and used in a number of different applications, depending on what is needed by a computer user. A MIDI sound card is an audio device that uses this type of interface and is installed onto a computer’s motherboard, which allows a musical instrument, often a keyboard, to be connected to the computer. The instrument can then be used as an input device to create music or audio information that can then be saved onto the computer.

A MIDI sound card has often been used in creating digital music. It will not typically actually record audio information, as the device used for input does not really play music into the computer. Any audio information is not sent as waves of sound but as digital information indicating pitch, volume, tempo, and other pieces of information that can be translated to audio sound through the use of an audio editing program or similar software. This means the resulting audio from using a MIDI device typically sounds somewhat synthesized and may sound innately digital or computerized in nature.

Much like other types of sound cards, a MIDI sound card will typically allow a user to connect speakers and a microphone to the computer as well. Sometimes multiple sound cards are used to allow the MIDI card to be solely for input of audio, and a separate card to work as output to speakers or headphones. The input device used with a MIDI sound card is typically a keyboard, which will have a MIDI connector that runs from a plug on the keyboard to the sound card. These may be standard keyboards that can also produce music or specialized MIDI keyboards that do not make music and only serve as a digital audio input device.

http://www.canmoremedia.com/basic-midi-connections.html

Imaginary Interface Could Replace Screens and Keyboard

Can you imagine our imagination can replace screens and keyboard? Sounds like ridiculous right? But when I'm trying to search a new technology for today, the title "Imaginary Interface" attract me to get closer with this topic. Here, I'll give you some summary about the "Imaginary Interface".

A user draws an imaginary line in the operating plane of the Imaginary Interfaces device.

The 'Imaginary' Interface device combines a camera and computer to see and then interpret gestures. Researchers are experimenting with a new interface system for mobile device that could replace the screen and even the keyboard and gestures supported by our visual memory.

To operate Imaginary Interfaces, people use two basic commands. Making an 'L' shape with one's non-dominant hand (typically the left) 'opens up' a two-dimensional plane where the finger tracing interaction will take place; the L acts as the lower left corner of the plane in this example.

Users can 'pinch' with the dominant hand to select a point in space on this plane that can serve a function. As an easy frame of reference, a grid can be visualized based on the lengths of the finger and thumb in the L gesture as a 'Y' and 'X' coordinate, respectively. Pinching at approximately 3, 2 – or three finger-lengths up and two thumb-lengths over – could press a virtual button.

The Imaginary Interfaces device

With 'Imaginary' Interfaces, however, there is nothing to see, short term visual memory instead serves as the reference, like mimes, people can mentally record and 'touch' these make-believe elements.

Now, the innovation technology becoming faster and sometimes people cannot catch the technology products because of the fastest changing. But with the imagination, all people seems like they are in updated.

See you next time!

References:

http://www.technewsdaily.com/

http://www.technewsdaily.com/imaginary-interface-could-replace-screens- and-keyboards-0668/  

Credit to: Hasso Plattner Institute

Future Input Devices

Hai everybody! 

FIRSTLY,do you want to know more about the future input devices? Lets Check it out!

Do you imagine that our SKIN can be input devices in the future? it is certainly no longer plausible right? 

Chris Harrison and a team of researchers are showing off a method of  ”Using your Arm, Hand and Skin as an input device“.Its sounds weird right? but, it can be reality in our life someday..who's knows?

Skin Input-Hand Input

Skin Input-Arm Input

For your information,they have been able to workout a technique that detects where the tap touches and use that to control phones and music players and computers. As a result, An arm band worn by the user picks up acoustic signatures created by tapping on your arm with the other hand, or taping your fingers and thumb together on the same hand. They’re achieving accuracies in the 82-97% range but it gets even better.

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As a conclusion,

“The human body is the ultimate input device,” said Chris Harrison...

 The usage of this technology human being will start to step in the era of robotic life style.

SECOND, the second input devices is mouse..In the future, it will be mouseless.....Believe it or not??

"MOUSELESS"= Without MOUSE

Mouseless

Mouse Evolution

But this could all change in the Future. The innovator Pranav Mistry comes with yet another

proof concept of computer input that could change the way we communicate with our PCs. The Mouseless invention removes the requirement of having a physical mouse altogether but still provides the intuitive interaction of a physical mouse that we are familiar with.

As Pranav Mistry said,

Mouseless consists of an Infrared (IR) laser beam (with line cap) and an Infrared camera. Both IR laser and IR camera are embedded in the computer. The laser beam module is modified with a line cap and placed such that it creates a plane of IR laser just above the surface the computer sits on. 

The user cups their hand, as if a physical mouse was present underneath, and the laser beam lights up the hand which is in contact with the surface. The IR camera detects those bright IR blobs using computer vision.

The change in the position and arrangements of these blobs are interpreted as mouse cursor movement and mouse clicks. As the user moves their hand the cursor on screen moves accordingly. When the user taps their index finger, the size of the blob changes and the camera recognizes the intended mouse click.

VIDEOS: "Let's watch the demonstration" 

Visual Demonstration using invisible mouse

Reference:

http://www.taranfx.com/future-input-device-skin 

http://www.taranfx.com/future-of-input-mouseless 

Credit to; Pranav Mistry

What is ouput ?

What is Output ?

Output is data that has been processed into a useful form. That is, computers process data (Input) into information (Output). Users view or watch output on a screen, print it, or hear it through speakers, headphones, or ear buds. While working with a computer, a user encounters four basic types of output: text, graphics, audio, and video. Very often, a single form of output, such as Web page, includes more than one of these types of output.

An output device is any hardware component that conveys information to one or more people. Commonly used output devices include display devices, printers, speakers, headphones, and earbuds, data projectors, and interactive whiteboards.

Four types of output are text, graphics, audio, and video

Display Devices

A display device is an output device that visually conveys text, graphics, and video information. Desktop computers typically use a monitor as their display device. A monitor is a display device that is packaged as a separate peripheral. Some monitors have a tilt-and-swivel base that allows users to adjust the angle of the screen to minimize neck strain and reduce glare from overhead lighting. With some, you can rotate the screen. Adjustable monitor stands allow you to adjust the height of the monitor. Some have integrated speakers and or a built-in Web cam. Monitor controls permit users to adjust the brightness, contrast, positioning, height, and width of images. Most mobile computers and devices integrate the display and other components into the same physical case.



LCD Monitors and LCD Screens

An LCD monitor is a desktop monitor that uses a liquid crystal display to produce images. These monitors produce sharp, flicker-free images. LCD monitors have a small footprint, that is, they do not take up much desk space. Most are wide screen, which are wider than they are tall. You measure a monitor the same way you measure a television, that is diagnolly from one corner to another.

Plasma Monitors

A plasma monitor is a display device that use gas plasma technology, which sandwiches a layer of gas between two glass plates. Like LCD monitors, plasma monitors can hang directly on a wall.

Other Output Devices

In addition to monitors and printers, other output devices are available for specific uses and applications. These include speakers, headphones, and earbuds, data projectors, and interactive whiteborads.

Speakers, Headphones, and Earbuds

An audio output device is a component of a computer that produces music, speech or other sounds, such as beeps. Three commonly used audio output devices are speakers, headphones and earbuds.
Most personal computer and mobile devices have a small internal speakers that usually emits only low quality sound. Thus many users attach surround sound speakers or speaker systems to their computers to generate higher-quality sounds.

Most personal computer users attach high-quality surround sound speaker system to their computers

Data Projectors

A data projectors is a device that takes the next and images displaying on a computer screen and projects them on a larger screen so that an audience can see the image clearly. Some data projectors are large devices that attach to a ceiling or wall in an auditorium. Others, designed for the mobile users, are small portable devices that can be transported easily.

Data projectors can produce sharp, bright images

What is Input?

What are Optical Scanners? 

An optical scanner is any scanning technology that converts a physical image, text, or object into a digitized form that can be stored as a 2D image file on a computer.  3D scanners also exist, but they are not widespread and are sometimes based on  different technologies.   Price? Optical scanners have been around for decades and their price has dropped accordingly.  You can buy low-level used optical scanners on eBay for as little as 20 US dollars (USD)  and a new scanner on newegg.com for around 50 USD. Better optical scanners sell  for hundreds of dollars. How about the basic technology?  The basic technology underlying optical scanners is that of the charge-coupled device (CCD). A CCD consists of a capacitor array that is sensitive to light. 1D Wireless Blue-tooth & Zig-bee long-range laser scanners High performance Wireless Optical laser scanner With RIOTEC laser engine, No Moving parts inside LS6000B: 90M max. LS6000Z: Up to 250 units scanners in single cradle Ergonomic design & light weight for easy use 3 LED indicators DEMO different functions (power, RF communication, good read, charging) Up to 30,000 scans per full charge Cover with rubber for well protection One shot programming completes setting Cradle can be hands-free stand and receiver Bar Code Reader This multi-purpose handheld bar code reader provides the power of a bar code scanner,  a digital camera and document scanner in single cost-effective device.  EPSON V300 Photo Scanner Hardware input device that allows a user to take an image or text and convert it  into a digital file, allowing the computer to read or display the scanned object.  A scanner is commonly connected to a computer USB, Firewire, Parallel or SCSI port.   Card Reader Memory Card Readers: Just like a CD-R or floppy disc, you need a device to read  what is on the flash memory; this is where a card reader comes in. You can connect  the card reader to your notebook or PC through a USB port. Notebooks can also use  a PCMCIA reader.   Image Capturing Devices Digital Camera A digital camera (or digicam) is a camera that takes video or still photographs, or both,  digitally by recording images via an electronic image sensor. Most 21st century cameras are  digital. Digital cameras can do things film cameras cannot: displaying images on a screen  immediately after they are recorded, storing thousands of images on a single small memory  device, and deleting images to free storage space.  Do you know?? The majority, including most compact cameras, can record moving video with sound  as well as still photographs. Some can crop and stitch pictures and perform other  elementary image editing. Some have a GPS receiver built in, and can produce  Geo tagged photographs. Types of Digital Camera : Sony Cyber Shot DSCT200 Olympus MJU 780 High Resolution Digital Camera Evolution of camera Follow this link :   http://www.technewsdaily.com/digital-camera-history-the-evolution-of-the-camera-0478/ http://www.darkroastedblend.com/2010/05/evolution-of-camera.html  Digital Video Cameras Digital Video (DV) is an ideal format for anyone wanting to use a camcorder (DV camera)  to work with video on the PC or the Web. The most exciting aspect of DV editing is the  purity of the content. No matter how much you work with your video,  if you keep the data in a digital format, the video quality will be exactly the same. For the shooting, only high quality digital 3-CCD cameras are used that provide an  excellent image quality – upon request, we will also guarantee HDV.  These professional 3-CCD Chip cameras have the highest relative aperture  of all cameras currently on the market.  Instant Messaging and Web Cams The latest web cam from Genius, Look 110, works with Windows Vista, XP, 2000, Me, 98SE.  Whether you are creating video emails or hosting one-to-one video chats, this easy to use  web cam adds a personal touch to your online communication. Logitech Quickcam Zoom Web Cam Hewlett Packard RD345AA Web Cam How to use any Digital Camera as a web cam? Choosing a Webcam For Instant Messaging Quality. Quality of a webcam is determined by the type of sensor and many webcam's now use CCD technology as found in many Digital Cameras. Low end and Early web cams use CMOS sensors which offer lower quality so it is important to choose a webcam that offers a good enough resolution to deliver clear crisp images and smooth video.   Simplicity. Almost all of the webcams available today require a USB connection to the computer so it is important to check your PC or Laptop has this connector available. You will also want to find a Webcam from a reputable manufacturer some of which include Logitech, Microsoft, Labtec, Saitek, Hauppauge and Axis as they will offer simple and well tested software installations which should work with little or no configuration of your Instant Messaging software.  PLEASE CHECK! Also check that your webcam has a usable stand or connector to enable you to attach the device at a suitable position - monitor mounted webcams are often the best choice as they offer the best position and distance to capture a persons face for instant messaging. Price. The price of webcams do vary considerably and you can pay anywhere from ten to hundreds of dollars for a webcam. For instant messaging a mid range webcam should not only provide the best quality but also offer a good level of support and compatibility. Some webcams offer face tracking and zooming technology and if you want these features you will have to pay slightly more but this does make day to day use of the webcam a little easier as it will not require as much repositioning.