Tuesday, April 2, 2013

Digital divide

Digital divide

 

What is digital divide?

The expression "digital divide" refers to the existing gap between those who can use new digital technologies and those who can’t. This is a key issue of today’s society, since it also provokes a distinction between those who can access certain information and those who are unable to do so.

 Some experts and researchers consider the digital divide to be merely an economic problem that affects poor countries; although the greatest part of these technologies is manufactured in developing countries, those ones who can afford them lack the necessary literacy and knowledge of how to use them.
However, identifying the problem exclusively in the economic condition would result inappropriate: the digital divide expresses itself also in the impossibility to use digital technologies within a considerable percentage of the industrialized countries population. This means that even when people can afford buying a computer or a mobile phone, they are not automatically capable of using it.
Another aspect of the digital divide issue is the one that addresses empowerment, which is the ability to fully use the opportunities provided by digital technologies; even if those technologies were accessible and very easy to use, many people would still not be able to take full advantage of their potential.

 

Solutions to digital divide:

1- developing countries first build up the literacy/language skills, computer literacy, and technical competence that low-income and rural populations need in order to make use of  ICT.

2- Government can try to control the Internet by monopolizing control" and Norris et al. also contends.If there is less government control of it, the Internet flourishes, and it is associated with greater democracy and civil liberties

3- invest in stimulating, attracting, and growing creative technical and scientific workforce; increase the access to education and digital literacy; reduce the gender divide and empower women to participate in the ICT workforce; emphasize investing in intensive Research and Development for selected metropolitan areas and regions within nations

Sunday, December 23, 2012

excel spreadsheet and modelling





                                           what is an excel spreadsheet?


Microsoft Excel is a spreadsheet program which allows one to enter numerical values or data into the rows or columns of a spreadsheet, and to use these numerical entries for such things as calculations, graphs, and statistical analysis.

Spreadsheets (like Microsoft Excel) can be very useful for student interactive activities, interactive lectures, and instructor use for developing materials for class. Example aspects of spreadsheets that are relevant to science education are:
·         Using Excel as a calculator to explore what mathematical equations can tell us about how the real world works for specific input conditions or for a range of possible values.
o    The calculator can be pre-constructed with a focus on student exploration or students can be guided to construct their own calculators and then explore. The first option saves time but the second option prepares students to use Excel for their own projects and future activities.
·         Graphically displaying equations (analytical models) and real data.
·         Obtaining numerical solutions to more mathematically complex models.
·         Graphically comparing results from a model and observations.
·         Statistical analysis including mean, standard deviation, error bars on graphs, linear and polynomial fits, multivariate analysis, etc.
·         Spectral analysis (Fast Fourier Transforms).
·         Displaying histograms of students results or student response to exams or questions.

                                     what is spreadsheet modelling?

A spreadsheet model uses a spreadsheet to explore different possible answers. These models are usually financial, mathematical or scientific. This is sometimes called “what if” modeling and shows what will happen to the results if you change some of the data within a spreadsheet. It can also be used to discover simple rules within the model. In the context of the examination, you may be asked to build a simple spreadsheet model and change data within the model, or even the model itself, to produce different results.

Saturday, September 8, 2012

System life cycle


 The systems life cycle (SLC) is a methodology used to describe the process for building information systems, intended to develop information systems in a very deliberate, structured and methodical way, reiterating each stage of the life cycle.

The system life cycle in systems engineering is an examination of a system or proposed system that addresses all phases of its existence to include system conception, design and development, production and/or construction, distribution, operation, maintenance and support, retirement, phase-out and disposal.

System Analysis
In this phase, the current system is studied in detail. A person responsible for the analysis of the system is known as analyst. In system analysis, the analyst conducts the following activities.

Needs Analysis
This activity is known as requirements analysis. In this step the analyst sums up the requirements of the system from the user and the managers. The developed system should satisfy these requirements during testing phase.

Data Gathering
In this step, the system analyst collects data about the system to be developed. He uses different tools and methods, depending on situation. These are:
- Written Documents
The analyst may collect the information/data from written documents available from manual-files of an organization.
- interview is another data gathering technique.
-Questionnaires
Questionnaires are the feedback forms used to collect Information.
-Observations 
In addition to the above-mentioned three techniques to collect information, the analyst  (or his team) may collect Information through observation.

After completion of this step the collected data about the system is analyzed to ensure that the data is accurate and complete.
then the requirements collected for the system are documented in a presentable form. It means that the analysis report is prepared. It is done for review and approval of the project from the higher management.




Monday, February 13, 2012

differences between the central and the normal air conditioning systems

central conditioning systems:
It is an air conditioning system that uses ducts to distribute cooled and/or dehumidified air to more than one room, or uses pipes to distribute chilled water to heat exchangers in more than one room, and which is not plugged into a standard electrical outlet.

With a typical split system, the condenser and compressor are located in an outdoor unit; the evaporator is mounted in the air handler unit. With a package system, all components are located in a single outdoor unit that may be located on the ground or roof.

Central air conditioning performs like a regular air conditioner but has several added benefits:

    When the air handling unit turns on, room air is drawn in from various parts of the building through return-air ducts. This air is pulled through a filter where airborne particles such as dust and lint are removed. Sophisticated filters may remove microscopic pollutants as well. The filtered air is routed to air supply ductwork that carries it back to rooms. Whenever the air conditioner is running, this cycle repeats continually.

    Because the condenser unit (with its fan and the compressor) is located outside the home, it offers a lower level of indoor noise than a free-standing air conditioning unit.


 Through-the-wall air conditioners are a cooling option for buildings that do not have central air conditioning installed. The units are relatively cheap. They typically cost anywhere from two hundred to four hundred dollars, depending on the size. Most units are designed to cool only one room, though some larger units may be able to cool additional rooms as well. No matter how large the unit, the ability to cool additional rooms is limited because the vent that blows cool air is only in one room.
 A through the wall air conditioner works by sucking hot air from the room into the unit. The hot air that enters the unit is brought over the air conditioning condenser and cooled. The cooled air is pushed back into the room. The motor that runs the unit produces hot air. The air conditioner pushes the hot air from the motor out through the vents in the back of the unit so that it does not heat the room.

Monday, September 26, 2011

ICT Homework 3


Biometric Applications
Biometrics is the technology, which uses various individualistic attributes of a person to verify his or her identity. Various attributes include fingerprints, geometrical shapes of hands, retina, and iris in the eyes and so on. Biometric test offers a full-proof and highly secure method of verification to avoid security breech and unauthorized access to critical data and places. The characteristics used by biometrics technology are divided into two groups - physiological and behavioural.
  • Physiological characteristics involve face recognition, handprints and fingerprints, veins in hands, capillary vessels in eyes and so on.
  • Behavioralcharacteristics involve voice modulations, handwriting and signature style, and keystroke dynamics.

Fingerprint Reader & Scanner

 Biometric fingerprint reader or scanner is certainly the most appreciable achievement of this technology, which is sprouting as a breakthrough in security provisions. Based upon storing and comparing the key points of one’s fingers, these devices have proved their potential in areas like access control and employee attendance management.

Face Recognition 

Face recognition is becoming popular with companies suffering from loss of information and decrease in productivity due to inappropriate security measures. At the same time, big organizations, airports and other high-alert areas are also developing fondness towards the technology. Face recognition technology is indeed the most appreciable application of biometrics, as it offers significant improvement over existing security products.

Friday, September 23, 2011

ICT Homework 2

                    Bluetooth 
Bluetooth is a proprietary open wireless technology standard for exchanging data over short distances (using short wavelength radio transmissions in the ISM band from 2400-2480 MHz) from fixed and mobile devices, creating personal area networks (PANs) with high levels of security. Created by telecoms vendor Ericsson in 1994,it was originally conceived as a wireless alternative to RS-232 data cables. It can connect several devices, overcoming problems of synchronization.
Bluetooth is managed by the Bluetooth Special Interest Group, which has more than 15,000 member companies in the areas of telecommunication, computing, networking, and consumer electronics. The SIG oversees the development of the specification, manages the qualification program, and protects the trademarks.To be marketed as a Bluetooth device, it must be qualified to standards defined by the SIG. A network of patents is required to implement the technology and are only licensed to those qualifying devices; thus the protocol, whilst open, may be regarded as proprietary.
Bluetooth is a standard wire-replacement communications protocol primarily designed for low power consumption, with a short range (power-class-dependent, but effective ranges vary in practice; see table below) based on low-cost transceiver microchips in each device. Because the devices use a radio (broadcast) communications system, they do not have to be in visual line of sight of each other, however a quasi optical wireless path must be viable.

Monday, September 19, 2011

ICT Homework


portable entertainment devices,shuch as:mp3 or DVD-players,which
allow people to listen to music or watch films, are now commonplace.
what do you think are the main advantages and disadvantages of 
this development?



MP3 Players:
-Advantages:-
1-It is portable.
2-Its used for viewing images and pictures.
3-We can record anything we want with the mp3 player.
4-Listening to the radio is also a use of the mp3 player.
5-Watching videos.


-Disadvantages:-
1-We must use headphones.
2-The screen is small.
3-The vision is not clear.
4-The memory space is not enough.
5-we have to recharge it continuously.


DVD Players:
-Advantages:-
1-It has a USB port.
2-IT has a wierless connection.
3-We canlisten to music.
4-High definition.


-Disadvantages:-
1-It doesnt play all formats of videos.
2-Most of the dvd players have connected to a television.