Expert Systems

Question 1

Expert System

Answer 1

Use knowledge base and set of rules to provide diagnosis or recommendation on actions

Contains
Knowledge Base
Inference Engine
User Interface

Question 2

Knowledge base

Answer 2

Database of knowledge
Entered by expert in that area
Allows storing and retrieval of those knowledge

Question 3

Inference Engine

Answer 3

Makes judgement and reasoning using the knowledge base and user responses
Based on a set of rules

Question 4

Application of Expert System

Answer 4

Medical Diagnosis
Car Mechanical Diagnosis
Financial Advice
Identifying plants and birds

Question 5

Forward Chaining

Answer 5

Chains the rules to form a line of reasoning

Starts with a set of conditions and chaining moves towards a final conclusion

Question 6

Backward Chaining

Answer 6

Starts with a known conclusion

Works in reverse to find the path where the conclusion came from

Question 7

Batch Processing

Answer 7

Processing batches of data in a certain time
Data collected and stored as batches, and processed together.
Batch processing is efficient (as no switching tasks is needed)
Better utility of the system (can process when the system is not that busy)

Question 8

Online processing

Answer 8

Also refers to Interactive Processing
Online processing system deals with data in transactions. Those transactions are usually small amount of data process together.

NOTE: Online does not refer to “connect to Internet”, but “active” or “connected”, e.g. the system is online

Bank transactions is an example. Money transfer must be done in a transaction like:
- Ensure balance in account B
- Add to account A
- Deduct from account B
- Record the transaction detail in database
All of the above must be done at the same time.

Question 9

Realtime processing

Answer 9

Realtime processing data as soon as it is inputted.
Used in system that the action must be taken immediately (or ASAP)

e.g. Air traffic control, the condition of the plane must be report and action taken immediately

Question 10

Master file

Answer 10

Collection of fields about a main element of a data system

Usually more permanent data (like student information)

Question 11

Transaction file

Answer 11

Data stored is normally used to update the master file.

Temporary

Question 12

Payroll system

Answer 12

Company have a system register the time employee arrive and leave
The record will place in transaction file
Calculate the hours of work and salary using that
System process in batch (e.g. all employee at the end of a day / month, no urgency needed) and update the master file at once

Question 13

Customer Order

Answer 13

Taking customer order uses online processing
e.g. for shopping web site, when a customer checkout
- Update Inventory file
- Update shipping file
- Update payment file
- Update customer file
All the above should complete in one single transaction
The above updates will be placed in some temporary transaction data, and update all the master files in one transaction.
In a database system, transaction will “rollback” if any of the operation within failed. For example, if there’s not enough inventory, the payment instruction will be cancelled and customer will not be charged.