6.8 : Expert systems Flashcards
1
Q
what is the definition of an expert system ?
A
expert systems are computer software that are designed to mimic (copy) the expertise and knowledge of a human expert in different field and subjects.
2
Q
what are the different examples of an expert system ?
A
- prospecting for oils and minerals
- diagnostics ( engine faults and faults on a circuit board )
- medical diagnostics
- strategy games ( chess)
- tax and financial planning
- route Scheduling for delivery vehicles
- identification of plants , animals , and chemical compounds
3
Q
what are the general information about expert systems ?
A
- expert systems are often used to advice non-experts in situations where a human expert in unavailable.
- they all tend to work in the same way
- someone comes along and asks them advice about a problem within their specialty.
- the expert asks a number of questions to help them formulate an answer
- the dialogue continues until the expert can offer one or more solutions to the problem
- expert systems are a form of artificial intelligence
- the first expert system was created in the 1970s
4
Q
what are the advantages of an expert system ?
A
- they offer a high level of expertise
- they offer high accuracy
- the results are consistent
- they have the ability to store vast amounts of ideas and facts
- they offer an unbiased reports and analysis of the facts
- they indicate a probability of any suggested solution to being correct
- they never forget to answer a question when determining the logic
- using expert systems reduces the time taken to solve a problem
5
Q
Disadvantages of expert systems ?
A
- users of the expert system need considerable training to ensure that the system is being used correctly
- the set-up and maintenance are very high
- they tend to give very cold responses which may not be appropriate in certain medical situations
- the system is only as good as the information/facts entered into the system
- errors in the knowledge base can lead to incorrect decisions being made.
6
Q
Explain the user interface ?
A
- this is the method by which the expert system to interact with a user
- it allows interactions through dialogue boxes, command prompts or other input methods
- the question being asked usually only has a yes / no answer and is based on responses to previous questions
- the user-interface is designed to be simple to use
7
Q
Explain the inference engine ?
A
this acts like a search engine , examining the knowledge base for information that matches the user’s query
- this is the main processing element of the expert system
- the inference engine acts like a search engine by examining the knowledge base for information / data that matches the queries
- it is responsible for gathering information from the user by asking a series of questions and applying responses where necessary , each question being asked is based on the previous response
- the inference engine is the problem-solving part of the expert system , which makes use of the inference rules in the rules base
- because the knowledge base is a collection of objects and attributes , the inference engine attempts to use the information gathered from the user to find an object that matches
8
Q
Explain what is the knowledge base ?
A
this is a collection of facts and rules , the knowledge base is created from information given by a human experts , it is used to provide a diagnosis or a set of recommendations.
- the knowledge base is a repository of facts
- it stores all knowledge about an area of expertise obtained from a number of expert resources
- it basically a collection of objects and their attributes
9
Q
Explain the rules base ?
A
- The rules base is a set of inference rules
- they are used by the inference engine to draw conclusions
- they follow logical thinking , usually involving a series of IF statements.
10
Q
Explain the explanation system ?
A
- this informs the user of the reasoning behind the expert system’s conclusion and recommended action
- and it also gives recommended action and the probability of the accuracy of its conclusion.
11
Q
how to set-up an expert system ?
A
- first information needs to be gathered from written sources such as textbooks , research papers and the internet
- then the information gathered is used to populate the knowledge base , which first needs to be created
- a rule base needs to be created , this is made of a set of instructions followed by the inference engine so it can draw conclusions
- the inference engine itself needs to be set-up , it is a complex engine since it is the main processing element , making reasoned conclusions from the data in the knowledge base
- they user interface system needs to be developed so the system and the user can communicate
- once the system is set-up , it needs to be tested by asking the system about a condition with known outcomes and so it can be compared and any changes are made to the system
]
12
Q
what are the three examples of expert systems ?
A
- medical diagnosis
- route scheduling for delivery vehicles
- oil prospecting
13
Q
how does the medical diagnosis expert system work ?
A
Input screen :
- first of all an interactive screen is presented to the user
- then the patient is asked questions about their illness
- the user will answer these question with a yes/no answers
- a series of questions are asked and they are based on the user’s response to the previous questions
Expert system processing :
- the inference engine will use the data that the user has entered to look for possible matches in the knowledge base
- the rules base is also used in the process
- once the match has been found the system will give a probability of how accurate the diagnosis wase
- the system will also give possible solution and remedies and recommendations on what to do next
- the system will also include reasons on why has the system gave this diagnosis so that the user can validate the symptoms or suggested treatments
output screen :
the diagnosis may be shown as text or images of the human anatomy to show where the symptoms may be
- the user may request further information from the expert system to narrow down the possible illness and tis treatment
14
Q
how does an oil prospecting expert system work ?
A
- an interactive screen asks questions ( either yes/no questions or multiple choice )
- questions are asked about geological profiles
- answers to question are typed by the operator
- the inference engine accesses the knowledge base using the rules base
- the system suggests the probability of finding oil deposits as an output
- it also indicates the probabilty of the depth of deposits ( %)
- the explanation system explains why did it come to theses conclusions
- it makes predictions about geolgical deposits above the soil
- it produces contour maps showing the concentration of minerals , rocks, oil etc.
15
Q
why is an expert system used for scheduling delivery trucks ?
A
- the fastest and cheapest route and the number of vehicles and drivers that should be used
