processing+requirements+for+AI

Storage requirements for common-sense knowledge
Common sense is the knowledge that can be used without any knowledge on a topic and are what our instincts tell us, things that are obvious. For example, the sky is blue. How do we store common-sense? One cannot just begin to read a book and achieve a lot of common-sense. Everyone has different levels of common-sense. Common-sense requires experience, and our memory stores it from our emotions or reactions to situations. You cannot exactly have a lot of common-sense without any facts. For example, you remember the time you were once burnt by fire, but it is not necessary to know the facts of the fire as one can tell that it is hot and needs to be careful with it.

Knowledge base
The knowledge base is the part of the expert system that contains all the facts and information that it needs to give solutions and solve problems. The knowledge base contains a system of rules for determining and changing the relationship among those facts. The facts are stored in a database which are then organised in categories. An expert system’s knowledge base must be constructed by a user, an expert, or a knowledge engineer.

//__There are two types of knowledge bases:__//
 * Machine-readable knowledge bases store knowledge in a computer and they usually have automated deductive reasoning applied to them. They contain a set of data, which often comes in rules that describe the knowledge in a logically consistent manner.
 * Human-readable knowledge bases are designed to allow people to retrieve and use the knowledge they contain, primarily for training purposes. The main benefit from this knowledge base is that it can help a user find an existing solution to his or her current problem

Inference engine
An inference engine is a computer program that tries to derive answers from a knowledge base. It is the "brain" that expert systems use to reason about the information in the knowledge base for the ultimate purpose of formulating new conclusions. Inference engines are considered to be a special case of reasoning engines, which can use more general methods of reasoning.

In simple rule-based systems, there are two kinds of inference, //forward chaining// and //backward chaining//.

//Forward chaining// is when the data gets put into working memory. This triggers rules whose conditions match the new data. These rules then perform their actions. The actions may add new data to memory, thus triggering more rules. And so on. This is also called //data-directed// inference, because inference is triggered by the arrival of new data in working memory.

//Backward chaining:// the system needs to know the value of a piece of data. It searches for rules whose conclusions mention this data. Before it can use the rules, it must test their conditions. This may entail discovering the value of more pieces of data, and so on. This is also called //goal-directed// inference, or //hypothesis driven//, because inferences are not performed until the system is made to prove a particular goal (i.e. a question).

=Social and Ethical Issues=

Responsibility Scenario
//(adapted from Computer Ethics)//

A Nevada woman underwent routine surgery in a hospital. The operation was completed without complication. However soon after, she was administered pain relief by a computerised dispensing machine (a medical expert system). Unfortunately, the system mistakenly instructed hospital staff to pump more than 500 milligrams of pain-relieving drugs into her body and within 30 minutes of the successful completion of the operation, she went into a coma. Five days later she was dead. The patient’s lawyer launched a damages suit against the hospital for incorrect and irresponsible use of a medical system. Is the hospital responsible?

Who should pay?
Examine the roles of the stakeholders and for each, give reasons for/against as whether that stakeholder holds any responsbility for the issue: · the [|knowledge engineer] · the informant (expert/s) · the programmer · the company that sold it · the hospital who purchased the system