Personal and public communications

IT concepts to address in this topic

Technologies

• Personal digital assistants (PDAs) and handheld digital devices

• Global positioning systems (GPS), navigation systems and geotagging

• Cell/mobile phones

• Digital radio and TV

• Embedded systems

Knowledge of technology

In order to study and evaluate the social and ethical issues involved in the use of personal and public communications, the student must have an understanding of related technological concepts. These may include:

key terms

  • convergence,
  • teleconferencing, videoconferencing,telecommuting,
  • digital television,
  • push–pull technologies
  • mobile phone and associated services and uses: the mobile phone has a widespread use nowadays, and is used for personal or business related communications, whether locally or internationally. Services such as internet and its associated services, radio, television, news updates, weather forecasts, and financial data and information are offered, among more.
  • digital entertainment versus live entertainment: live entertainment pertains to any forms of entertainment which is viewed directly without the broadcast or delivery using IT systems. Examples of live entertainment are plays and operas, music concerts, stand-up comedy among others.
  • contents of digital entertainment, for example, violence, pornography and realism: a prevalent issue with digital content is its appropriateness. Content with too much violence and gore, nudity, sexual references, realistic wartime simulations, vulgarisms and profanity, or any other form of explicit material must be assessed in the digital content, whether it be a movie, song, video or computer game, or website. Once rated and assessed, age limitations are imposed, sometimes against children, all minors, or specific countries depending on the region and its laws, culture, and policies.
  • features of telecommuting, for example, environmental aspects, flexibility, productivity, business and social relationships

How GPS works

  • The Global Positioning System (GPS) is actually a constellation of 27 Earth-orbiting satellites (24 in operation and three extras in case one fails).
  • The U.S. military developed and implemented this satellite network as a military navigation system, but soon opened it up to everybody
  • Each of these 3,000- to 4,000-pound solar-powered satellites circles the globe at about 12,000 miles (19,300 km), making two complete rotations every day.
  • The orbits are arranged so that at any time, anywhere on Earth, there are at least four satellites "visible" in the sky.
  • A GPS receiver's job is to locate four or more of these satellites, figure out the distanc­e to each, and use this information to deduce its own location.
  • This operation is based on a simple mathematical principle called trilateration. Trilateration in three-dimensional space can be a little tricky, so we'll start with an explanation of simple two-dimensional trilateration.

How trilateration works

  • Imagine you are somewhere at Sandford and you are TOTALLY lost -- for whatever reason. You find a friend and ask, "Where am I?" He says, "You are 100 M from A block." You could be anywhere on a circle around A bolck that has a radius of 100 M, like this:

You ask somebody else where you are, and she says, "You are 50 M from N block." Now you're getting somewhere. If you combine this information with the A block information, you have two circles that intersect.

You now know that you must be at one of these two intersection points, if you are 100 M from A block and 50 M from N block.

  • If a third person tells you that you are 40 M from F block, you can eliminate one of the possibilities, because the third circle will only intersect with one of these points. You now know exactly
  • where you are – The Staff room

This same concept works in three-dimensional space, as well, but you're dealing with spheres instead of circles..

Geotagging

Geotagging is the process of ,adding and matching geographical identification data (like maps and images) to various media such as photographs, video, website, or emails. These data usually has latitude,

longitude coordinates, and altitude.

• Cell/mobile phones

• Digital radio and TV

• Embedded systems

Services

• Accessing, distributing and sharing text, photos, video, audio, television via portable and non-portable digital devices

• Synchronization of information between portable systems, desktop systems, servers and web-based Services

• Videoconferencing

• Remote access: for example, teleworking, distance learning

• Telephony: voice over internet protocol (VOIP) – Check: http://www.howstuffworks.com/ip-telephony.htm

Reference:http://kennedyb.wordpress.com/2011/11/16/3-5-personal-and-public-communications/