1, The process of communication in IT
Describe the process of conventional communication. Show the process when we use a mobile phone.
What is noise? How can we avoid it, or its distorting effect?
Why is it good if the information is redundant?
Define the two different meanings of information.
Define the unit of amount of information.
Sender-encoder-pipe decoder-receiver presume
Fundamentals:
Notice: signal, signal sequence, data that have information; the sender communicates toward the receiver.
Sender: the source of information – can be a person, animal, software, machine etc. That produces
Signal converter: signals need to be converted physically to make them fit for relaying e.g. analogue sound to analogue electric signal.
Encoder: encodes signals, notices to another code e.g. encode analogue to digital, compress digital data etc.
Pipe: a wire, transmission medium physical field that relays the signals.
Decoder: decodes the encoded signals.
Receiver: who or what interprets and stores the notice, signals.
Noise: it mixes with the notice, superimpose and distorts that. In a digital signal false digits can appear.
Two-way communication is almost the same.
Noise – protection
Analogue signal: noise filtering, proofing e.g. soundproofing, electromagnetic shielding. We can increment the signal/noise ratio as well.
Digital signal: proofing. If the noise caused errors in the databits than correcting procedures, parity bits( e.g. the 9th bit signals that the data is even or odd. If one bit fails than the parity is not equal to he parity bit),
Redundancy can also be a protection tool.
Redundancy:
When a notice is redundant, the information is not given inthe shortest way.
The amount of data is much more than the amount of information.
This is the base of the compression as well.
In a redundant dataset errors can be repaired more likely if the redundancy is bigger.
Communication process with the mobilephone
Specify the elements of the communication process, fundamental ideas.
E.g. notice: What we tell to the phone; encoder: the microphone; pipe: the electromagnetic field that transmits the radiowaves.
The steps of phoning are well-known.
The amount of information
The less the probability ofan event’s or signal’soccurrence the bigger the amount of information.
If a signal’s occurrence is granted then it represents zero information.
The unit of amount of information: 1 bit (binary unit) – if one of two equal signals with equal probabilities occurs, it means one bit information. It is independent from the meaning of the sign.
The amount of information of a set of signals is independent from its meaning. If we know the occurrence of probability of the signals, we can calculatethe informationwith mathematical formulas.
Questions:
When we have a conversation andwe gesticulate during this, what are the encoder-decoder, the pipe and the noise?
Why is the ratio of signal/noise important?
2, Learning with the Internet, e-learning. Development of e-commerce and e-economy
Describe the usage of web pages and databases in learning
Describe e-commerce
We can find a lot of information on the Web. We can search the whole Internet with search engines or specialized thematic engines or we can search URL-s and use the open databases. By the topic we want to know we can choose from these options:
Search by author or topic
- We can search electronic, virtual libraries, like Neumann-ház. We are allowed to download the documents
- We can search the web pages of libraries or electronic catalogues (sometimes we can’t look at the documents via the Internet, only personally): OPAC (Online Public Access Catalogue) or MOKKA – the Hungarian version of OPAC.
- Electronic catalogues are more flexible than conventional libraries because we can place inquiries by a lot of point of views.
Thematic search engines – we can use them for learning
- Like startlap.hu, hudir.hu
We can search special learning portals or databases
- Like
- We can also find useful information on the pages of educational organizations like schools or universities.
- SDT (Sulinet Digital Knowledge Base) is a very useful page – a fantastic page for students both secondary school and high school. Tons of downloadable contents.
Keyword or mixed engines
- Common information pages: startlap.hu
- Search engines: google.hu, yahoo.com
Educational pages by subjects:
- Physics: fizika.lap.hu, nasa.gov
- IT: om.hu, kiberoktat.hu
- Etc
Development of e-commerce, advertising, shopping
The most widespread e-commerce thing is the appearance of the companies on the Internet. Here they offer their services, merchandise. They use their pages as advertising tools, offering ordering options as well. The number of shops using the Internet for advertising is increasing. Major shops, chain of shops offer their goods on the Internet too. These companies are from education, culture, media, catering etc. Nowadays we canfind every segment of economy on the web like industry, agriculture, trade or tourism. We can find ‘real’ webshops in the fields of ordinary trade.
The number of webshops and their offer is increasing. There are hundreds of webshops and their turnover is billions per year.
The advantages of electronic shopping are:
- We can shop at home or at our workplace, distance and traffic are not limits. Transport is by other services or by post.
- We can check the goods on the screen, we can compare the features to other offers or webshops.
- The supply of the webshops can be very large if they have connections with other stores’ databases.
- Internet has no borders. This can change our shopping opportunities and habits. We can buy British goods from Hungary and ask the delivery to Toronto, Canada.
- Some shops can offer their goods cheaply.
- In some cases we can get the purchased goods immediately (data, documents or tickets).
The process of shopping in online shops is happening with the help of a virtual basket, so we can check review the goods in them before paying. After we give our credit card number, he transaction passes. The we just wait for the courier or postman.
Mobile phone shoppingis an American way of shopping. Probably it will be used in Hungary as well.
Questions:
What is your opinion about SDT? Is it useful for learning?
Are there any disadvantages in buying via the Internet?
3, Common dangers of ICT (Information and Communication Technologies) vs. ergonomic environment and the right behaviour
Describe the dangers of modern ICT tools in the point of view of health and psyche.
Can the monitor, keyboard, printer, mobile phone and other peripherals have a health-damaging effect? How can we protect ourselves?
Analyze an ergonomic IT job.
How much effect does PCs and computer games have on kids and youngsters?
Can a passion for gaming or Internet dependency become abnormal?
Ergonomics is a science. It deals with the optimal relationship between a person and technical devices. It’s main purpose: How to design a machine to fit perfectly to the man’s physical and mental abilities, opportunities.
One of the most important things is that the machine cant do any harm the user. It has to fit to the size and the movement of the body and the hand and the organs of sense.
Regarding to IT, the communication between the user and the PC is very important. The system of symbols of the graphic operation systems and applications turned to a special user language during the past 15-20 years.
If the relationship between the user and the PC is not optimal, the result can be: descending performance, damage, disease.
The mobile phone: some say that these phones can do harm to the brain because of the electromagnetic radiation but it’s not proven so far.
The risks of a computer workplace
The monitor and lighting: the connection between the windows, the screen and the lighting – avoiding reflections.
Powerful sunshine and the visibility of the screen
The charging of the screen: dust can harm the eyes – pain, weeping.
The distance of the eyes from the screen: 60-70 cm’s. Resolution; the size of a pixel – strain.
Protection: quality 17” LCD monitors, the right placement, proper lighting.
The work desk, chair, keyboard and mouse
The size, the position of the desk, monitor and the chair can make the user have uncomfortable posture (back and neck pains, stiffening
The keyboard and the mouse can force the arms and the wrists to have unnatural postures. The constant typing can cause pain in wrists and fingers.
Protection: carefully chosen desk for the peripherals as well. Swivel chair with castors; setting the right height. Having rest frequently; gymnastics, right posture, ergonomic keyboards. Optical mouse etc.
The PC case and the printer
The coolingfan and sometimes the hard drive can be very noisy or resonate. Constant noise can make the user tense.
The steam of the laser printer is unhealthy.
Protection: silent fans, frequent airing.
The expectations for the applications
The user interface has to use the most up-to-date visual items (icons, tools, windows, menus etc).Clear, simple and easy to use.
Intelligent, user-friendly communication with the user
Reliable operating.
Computer games – addiction
Computer games develop faster and faster. They become more interesting, exciting and more realistic thanks to the growing performance of the computers and video cards (e.g. virtual reality).
Users who play regularly (hours per day) can become addicted.
The neglecting of studying or working.
We can experience the same of Internet browsing, chatting etc.
Adult materials that are harmful for kids can be accessed easily via Internet.
Protection: School education, parental care, self control!
Crimes
Not so many young people are involved. There are unauthorized data-using, security breach, virus-programming etc.
Questions:
What type of monitor would you prefer if price is not important?
How can you avoid the addiction to computer games?
4, Relationship in using software and the copyright
Sort software by their features.
Sort software by copyright. What types of software usage do you know? What is free software (freeware)?
How can we protect our compositions, intellectual products? What is copyright?
Sorting of software
Software consists of: computer programs, data and their documentation in file and printed format.
Operating system: it is the link between the computer and the user. The operating system interprets the user’s wishes toward the computer e.g. file copying, deleting, running programs. Modern OS’ have graphic interface like Windows, MacOS, Linux.
Developer systems: Programming languages like BASIC (the simplest and most popular among everyday home computer users); Assembly (the professionals’ language), C, Pascal, Java, Visual Basic etc.
Applications: for office use (Microsoft Office, Open Office), engineering (AutoCAD), games, multimedia (media players); for everyday usage.
Software in the point of copyright view
Free software (Public Domain): free, freely distributable, the programming code is also free for viewing
Freeware: free, freely distributable, but the programming code is kept secret. The copyright belongs to the author. We are not allowed to sell the software and to modify it.
Shareware: We can get them for free but we are allowed to use them for a limited time or they are not fully functional. We have to pay for the full version and have to register the program.
Semi-free programs: They are commercial programs but there is a discount for certain purposes (e.g. education).
Commercial programs: They have a price (some programs are very expensive) and we have restrictions for the usage (like we are allowed to install them only for on PC).
Licence agreement
It details the conditions of the usage of a program.
We are allowed to use the purchased software on limited number of machines (we are allowed to install it to the machines we bought the licence for).
We are not allowed to propagate. We can make one backup copy of it. We have to have the original installation disks.
We can send back the registration form or we have to register via Internet.
Software is an intellectual product as well (like novels, or an invention).
Ethics: a useful commercial program needs a lot work and skill to produce. The company who owns the program needs the income (e.g. to pay the employees’ salary).
Electronic products are easy to copy without any value loss.
Sometimes a program is copy protected, but generally it doesn’t take much time to crack the protection.
To force back computer piracy there are civilian organizations like BSA (Business Software Alliance). They are no authority so they can only advice the legal software usage.
Software can be handled as invention and protect them by patent but it’s not a simple process.
The copyright (1999 law 26) (Some more important excerpts)
The subject of copyright
1st §. Every composition in literature, science, art is copyrighted, even the public speech.
The product of computer programming and the documentation including applications and operating systems are also copyrighted.
The copyright doesn’t depend on quantity, quality or aesthetic features or value judgements.
The author has the personal and property rights from the birth of the composition. The author is not allowed to give up the personal rights.
It is the author’s decision to public the product (on the Internet as well).
The author has exclusive rights to every kind of usage of the product and to authorize any usage. The licence to use the product can be obtained by licence agreement. It can be a financial benefit for the author. The licence fee for the product must be proportional to the income if there is no special agreement.
There are some constraints of the copyright e.g.:
34th §. A part of the composition can be quoted freely in a reasonable extent with the notation of the source and the author.
Questions:
On how many PC’s can we use a program if we installed it to a server?
You have a desktop PC with a legal Windows XP. You just bought a notebook without an operating system. Are you allowed to install your only legal Windows to this notebook?
5, Analogue and Digital Pictures – digitalisation
Define and arrange pictures as signals.
How can you digitize a common, colour 2D picture as an analogue signal?
Explain the structure of a digital raster image (like BMP) and the regular parameters of the resolution.
What is the concept of the additive mixture of colours and where is it used? How can we encode the colour of the picture elements (pixels) binary?
Explain the concept of the RGB colour blending and encoding. What is the connection between the number of bits and the number of possible colours?
What is the concept of subtractive mixing of colours and where is it used?
Give some details of vector graphic pictures. What is the difference between these and the pixel graphic pictures?
The picture as an analogue or digital combined signal
The eye is our biggest capacity information channel
The signal is a phenomenon that can be sensed and comprehended by our organs. It relates to other things so it has a meaning. A grouping: visual, audio, olfactable, non perceptible.
We can call a visual signal everything that is visible and acts as a signal – mostly 2D drawings, photographs, videos, maps, symbols etc.
It can be pictorial (drawing, photograph, video etc.) stylized (map, technical drawing, conceptual design, icon etc.) and symbolic (characters, numbers, bar code etc.)
Analogue signal: macroscopic physical signal, continuous or it can be considered continuous (it can represent any value between two limits like time, colour, current, voltage, the angle of the clock-hands if they are signals)
Digital signal: it can be represented by numbers, binary encodable (a set of discreet signals that is given with numbers).
It is important that in practice we can approximate the analogue signal with a sufficient amount of numbers. From this numbers we can restore the original analogue signal with high accuracy e.g. photograph-digital picture-printed picture.
Digitalization of the analogue picture
Conventional pictures are analogue signals or signal sets. The number of colours of a picture can be very large or the definition and resolution very high. It depends on the size and the quality of the chemical grains.
The two main steps of the digitalization of an analogue picture
The reducing of the picture to pixels or dots e.g. we put a 800 column-600 row grid to the picture in thought. Every square is a pixel, so we resolve the picture to 800*600 pixels.
The colour coding of the picture – we assign a number to every pixel. We digitalize automatically, mostly with the help of a computer scanner.
Practical examples are the digital cameras and recorders. They digitalize and store the analogue picture made by the lens automatically.