Technical documentation is produced specifically for the system analyst and the programmers. whether User documentation is provided to help the user with the new system.
Developing elements of technical documentation
Technical documentation consists of:
1. System documentation
It provides a detailed overview of the whole system
2. Program documentation
It is produced for those pieces of program code that have been written
Designing and developing elements of user documentation
User documentation is produced for several reasons, for example the user may not be familiar with the system so it will help him with various parts of the system until he becomes familiar. It is like tutorials.
It will include:
Screenshots and descriptions on how he will use the software
System analysis involves examining the existing system in detail.
The system analyst must find out why the system has to be changed, by:
1.Collecting information on how the existing system works
2.Establish the input, output and processing
3.Recording information
4.And finally, identifying the problem
The
first stage in system analysis, the system analyst has to collect
information about how the is the current system so he will use these
four methods:
1.Examining of documents
2.Interviews
3.Observation
4.Questionnaires
After
the system analyst has finished collecting the information he needs to identify the
input, output and processing and quit often this stage is done whilst
producing a data flow diagram.
The system analyst needs
now to record all the results in order to establish all the relevant features of the
existing system.
Data
flow diagram is a graphical method of recording the inputs, outputs and
processing that have been identified.
It
consists of four components:
1.Terminator
2.Processes
3.Flow arrows
4.Stores
Data
flow chart is a generally a method of designing a systems solution and so is
not found very frequently in the analysis stage.
Now
the system analyst can identify the problems in the old system. Since he
used the system data flow chart, it helped him to identify the problems.
After
the data flow diagram have been produced
they are examined together with the other results of analysis such as interview
transcripts and questionnaire analysis to identify the problems with the
current system.
ISBN numbers are created so that the first nine digits are information digits
and the last digit, the one you want to calculate, is a check digit. This last
number helps people notice and correct mistakes that might be made in recording
the information digits.
Here is an ISBN number: 0-205-12669-3. The digit 0 indicates the book is
written for English-speaking people. The number 205 and the number 12669
identify the publisher and the book published by that publisher.
The last digit, the 3, was chosen in the following way. Each digit is given
a weight by using the digits 1 to 10 and counting right to left.
(The digits of the ISBN information numbers are listed in order left to
right and weighted by counting down from 10 to 1.) The check digit is chosen to
be a number from 0 to 10 so that this weighted sum is a multiple of 11. That
is, the sum must be divisible by 11.
Let us see what sum we have so far with these particular nine
The check digit 3 was chosen because 129 + 3(1) = 132 and 132 is a
multiple of 11. 129 is greater than 11(11) = 121 and 14 less than
11(13) = 143. The only possible number from 0 to 10 to use as a check digit
is 3.
Sometimes the only choice for a
check number will be 10. Since this is a two digit number and cannot be used as
such, the Roman numeral 10, the symbol X, is used.
This system for assigning the last number of an ISBN number makes it possible
to detect errors made by writing a single digit incorrectly or by writing a
pair of digits in the wrong order.
As with all air conditioning systems the principle remains the same whereby the heat is removed from one area and replaced with chilled dry air and the hot air is expelled, normally to the outside atmosphere. As you can see from this typical example of a air conditioning system, the ambient air is drawn over the condensor that can best described as a ‘radiator’ as seen on motor vehicles but instead of water running through the system it contains a refrigerant gas.
On its journey around the system it has three main stages; the evaporator contains the sub-cooled refrigerant and air blows through its veins to release the chilled dry air into the room, the condenser contains the high temperature gas that once again air is blown through the veins collecting the heat as it passes through and this is then expelled outside.
Basic Operations
An air conditioner is able to cool a building because it removes heat from the indoor air and transfers it outdoors. A chemical refrigerant in the system absorbs the unwanted heat and pumps it through a system of piping to the outside coil. The fan, located in the outside unit, blows outside air over the hot coil, transferring heat from the refrigerant to the outdoor air.
Most air conditioning systems have five mechanical components:
• a compressor • a condensor • an evaporator coil • blower • a chemical refrigerant
Most central air conditioning units operate by means of a split system. That is, they consist of a ‘hot’ side, or the condensing unit—including the condensing coil, the compressor and the fan—which is situated outside your home, and a ‘cold’ side that is located inside your home. The cold side consists of an expansion valve and a cold coil, and it is usually part of your furnace or some type of air handler. The furnace blows air through an evaporator coil, which cools the air. Then this cool air is routed throughout your home by means of a series of air ducts. A window unit operates on the same principal, the only difference being that both the hot side and the cold side are located within the same housing unit.
The compressor (which is controlled by the thermostat) is the ‘heart’ of the system. The compressor acts as the pump, causing the refrigerant to flow through the system. Its job is to draw in a low-pressure, low-temperature, refrigerant in a gaseous state and by compressing this gas, raise the pressure and temperature of the refrigerant. This high-pressure, high-temperature gas then flows to the condenser coil.
The condenser coil is a series of piping with a fan that draws outside air across the coil. As the refrigerant passes through the condenser coil and the cooler outside air passes across the coil, the air absorbs heat from the refrigerant which causes the refrigerant to condense from a gas to a liquid state. The high-pressure, high-temperature liquid then reaches the expansion valve.
The evaporator coil is a series of piping connected to a furnace or air handler that blows indoor air across it, causing the coil to absorb heat from the air. The cooled air is then delivered to the house through ducting. The refrigerant then flows back to the compressor where the cycle starts over again.
Air Conditioner Filters
The most important maintenance task that will ensure the efficiency of your air conditioner is to routinely replace or clean its filters. Clogged, dirty filters block normal airflow and reduce a system’s efficiency significantly. With normal airflow obstructed, air that bypasses the filter may carry dirt directly into the evaporator coil and impair the coil’s heat-absorbing capacity. Filters are located somewhere along the return duct’s length. Common filter locations are in walls, ceilings, furnaces, or in the air conditioner itself.
Some types of filters are reusable; others must be replaced. They are available in a variety of types and efficiencies. Clean or replace your air conditioning system’s filter or filters every month or two during the cooling season. Filters may need more frequent attention if the air conditioner is in constant use, is subjected to dusty conditions, or you have fur-bearing pets in the house. If you use a disposable type filter, it’s always wise to keep several spares inside the house.
On the 13th of march (Wednesday) our ICT teacher took us to a field trip to Mazda which belongs to Towell, there we had some people telling us a few things about the company, and these are some:
First of all the company was found or established in 1972, they had the car pieces from Japan, whereas the dealers are in Oman.
They have a long organizational structure in which the information are carried out in a specific system. Talking about system, they have a backup system for important data. There are many departments inthis company such as finance, human resources and many others, all these departments use devices which involve ICT technology to make their work efficient and a lot faster and easier.
They are using devices that is specific for safty, for example biometric fingerprints, before we entre to the
departments, we saw a device ( Biometric fingerprints ) this device store templates of various characteristics of different people. A person is authenticated by matching his or her characteristics with those stored in the template database. Amazingly, these devices based upon biometrics technology are made capable enough to carry out the process of verification in 1-2 seconds, even if the database has thousands of templates stored in it.
They don’t only have teleworkers but also remote area workers who use VPN technology to log into their user accounts, each 90 days the password is changed so no interference or hacking occurs. You can book things online, but you cant pay though. Towell also uses expert systems which help people to recognize what problem they are facing by answering a few questions.
One last thing is that people there where so welcoming and friendly, I'd love to work with people with such personalities.
Listening to all those sayings I concluded that towel is a developed and up-to-date company which use modern technology. I really liked the trip and hope someday I own a company like Towell in the future.
Online shopping is the process whereby consumers directly buy goods or services from a seller in real-time, without an intermediary
Advantages of online shopping
1. Finding a product online is much more easier than looking for it in the local store. you can save some valuable time.
2. Now it is very easy to shop online because of the availability of internet every where in the world.
3. You don't have to waste your time in going to store and standing in front of the crowd
4. You will enjoy the freedom of price flexibility. If you don't like the price of a product from an online shop, you can switch to other online to store to look for cheaper price.
5. Most of the store provides money back guarantee. Although it is very difficult to get back the money but most of the seller do provide money back grantee for a specific period of time.
6. You have infinite option to choose a product.
7. If you don't find any product within your country then you must need to shop online from a international store.
Disadvantages of online shopping
1. The main disadvantage is - you can not receive the product immediately. you have to wait until the product arrives.
2. You don't know about the actual quality of the product. Sometimes the description of the product might be different than the actual product. As a result you might end up with inferior quality product.
3. Shipping charge and shipping delays are one of the main disadvantage of shopping online. Some people just can't wait.
4. Sometime you may face Delivery risk. Delivery risk occurs when the seller fails to deliver the original product or delivers a damaged (inferior/duplicate) product.
5. As online shopping is becoming very common the number of online scam and fraud is also increasing. This is why a buyer should always buy from trusted websites.
6. You wouldn't like to buy any clothing products because you won't be able to know whether they will look good on you or not.
Steps: 1. Ensure that you know the identity, location and contact details of the online retailer. 2. Find out more about a company's reputation 3. Find out about billing, guarantees and delivery before you buy. 4. Read the site's privacy policy. 5. Only use secure websites if you are transferring funds via the site. 6. Take care when entering information 7. Use a credit card with online fraud protection 8. Record purchase details. 9. Be aware of email scams designed to part you from your credit card information
.JPG)
.JPG)
.JPG)
