A Understanding Knowledge Based Systems Computer Science Essay

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Banana Software company wants to expand their business in the future. I have been assigned the assignment and write the information of analyzing MYCIN as a knowledge-based system (AI). It is to let the staff know what KBS are all about.

So, firstly, MYCIN is a type of expert system that used Artificial Intelligence(AI) to identify infectious diseases or medical diagnosis. It communicates, interprets and gives explanations to the questions that just been asked by the user and it responses back with a list of possible diagnoses and recommend treatment. The physicians are usually using this MYCIN program. 

i. In this section, I am going to explain the Data, Rules and Structure of MYCIN. Data can information or document and it appears in a variety type form of text, numeric values or symbols. Data also known as accurate, distinct and static things and raw observations of the specified area of interest.

We need to process the data first before we can actually use it. The data also can be viewed as a structure or graph. In this case, MYCIN's data would be the medical report such as the statistic.

Next, the rules of MYCIN. Rules are used as a way to store and manipulate knowledge to interpret information in a useful way. They are often used in artificial intelligence(AI) applications and research. As for MYCIN application, it has over 450 variety types of rules and IF-THEN rule is one of them with particular certainty factors. This is the example of IF-THEN rule:

IF the infection is primary-bacteremia

AND the site of the culture is one of the sterile sites

AND the suspected portal of entry is the gastrointestinal tract

THEN there is suggestive evidence (0.7) that the infection is bacteriod.

Finally, the structure of MYCIN. A knowledge based system is the software containing source of knowledge called a knowledge base. it is a mechanism for referring to existing knowledge and generating new knowledge that is, inference, reasoning and explanation.

ii. A knowledge-based system is a computer program that cause and uses knowledge to solve complex problems. The basic advantages offered by such system are documentation of knowledge, intelligent decision support, self learning, reasoning and explanation.

Knowledge is reflected on a human understanding of a subject matter that has been acquired through proper study and experience. All of the information and data is obtained from a group of humans earlier and later represented using a range of knowledge representation methods rules, frames and scripts.

Also, knowledge is derived from information in a similar way as information is derived from data. It can be considered the production and combination of human perception processes that helps them to represent significant conclusions.

MYCIN was a rule-based expert system for the diagnosis of infectious blood diseases. It also provided a doctor with therapeutic advice in convenient, user-friendly manner. As for the inference engine, it is a computer program or also known as reasoning engine and it operates like a brain. It is used by expert system to reason about the information in the knowledge base and makes decisions about actions to be taken.

The processes of the inference engine are firstly, the system gather a collection of common principles which can potentially be applied to any difficulty, these are stored in the knowledge base. Then, the system also stores a compilation of explicit details that applied to the existing problem, these are kept in working memory. Both these sorts of information are processed by the inference engine.

iii. Artificial Intelligence (AI) is the intelligence of machines or software. It is also the study of ideas that enable computers to be intelligent. Intelligence might be refer as the competence to obtain and apply knowledge. AI is the component of computer science concerned with design of computer systems that demonstrate human intelligence

The traits of Artificial Intelligence are it reacts to situation flexibly. It makes sense of vague or flawed messages. It assigns virtual significance to elements of a circumstances. It finds similarities even though the situations might be different And it represents distinctions between situations even though there may be many similarities between them.

A machine is considered as intelligent if it demonstrates human personality generated through natural intelligence. In one way, Artificial Intelligence is the study of human thought processes and moving toward problem solving in a symbolic and non algorithm way.

Heuristic means rule of thumb, or a practical rule that does not give a assurance of success, AI does not only to offer answers to problems for which there are no known efficient solutions, but also believes difficulties that can be solved, although the distinctive ways take a long period of time.

The objectives of knowledge based system are, it supplies a high intelligence level. It helps people in discovering and developing unknown fields. Also, gives a huge amount of knowledge in different part. Aids in management of knowledge stored in the knowledge base.

With today's technology system, the knowledge based system has worked out the social difficulties in a better way than before. Acquires new view by stimulating anonymous situations. It gives considerable software efficiency development. Significantly decrease the cost and time to build up computerized systems.

iv. An expert system is a computer application that tries to impersonate expert's reasoning processes and knowledge in resolving particular problems. MYCIN also been using this expert system to diagnose and treating bacterial infections. They utilize a rule-based expert system. Expert system usually divided of at least 3 major component of knowledge base, user inference and inference engine.

The user inference the technique by which the expert system communicate with a user. These can be through dialog boxes, command prompts, forms, or other input methods. Some expert systems work together with other computer applications, and do not communicate directly with a human. In these cases, the expert system will have an interface system for transactions with the other application, and will not have a user interface.

Meanwhile the knowledge base it is a compilation of facts, rules and procedures arranged into schemas. The collection of all information and knowledge about a specific field of concern. The facts may be derived from a reliable resource of information that is built in the system. The rules incorporate both the production rules that apply to the domain of the expert system and the heuristics that are offered by the domain expert in order to make the system find clarifications more proficiently by taking short cuts.

The inference engine is the main processing element of the expert system. It is a computer application that attempts to obtain answers from a knowledge base. It is the brain that expert systems use to reason about the information in the knowledge base, for the definitive reason of formulating new conclusions.

As mentioned earlier, AI is one of the component in the computer system and its function is likely to exhibit human intelligence. The AI traits are it is very reliable to situation. It can identifies connections even when the situations are slightly unusual.

TASK 2: Pass 2.1

Domain Expert





Knowledge Engineer


Expert System

Figure 1.1: General structure of knowledge based system

The company has now been awarded the contract to develop a new KBS for a local hospital. I have been assigned by the company to complete the initial design for the

application and I will present on this report about the process and functions of the application.

Expert system refers to a computer program that tries to imitate human experts by the system's ability to provide advice, to instruct and implement intelligent tasks. Figure 1.1 above shows the general structure of knowledge based system.

The process of constructing an expert system needs proper planning from the very beginning in order to avoid error during the development of this system. It is general to get an expert systems tool. The process of developing this application requires step-by-step process.

The major components of this expert system are, domain expert and knowledge engineer. So firstly, the domain expert is a person who is skilled in a certain area. A domain expert is a person with unusual knowledge or capable in a certain area of endeavor. A person should also have fundamental understanding on other types of work. After done with their task, they can proceed their task to the knowledge engineer.

Then move to next process, resources. Resources refer to any type information or data that is useful and related to the expert system. Both domain expert and resources can be gather to the next process, the knowledge engineer.

So, the knowledge engineer. This person is responsible to obtain and represent the knowledge. But some of them can do the computer programming as well. Knowledge engineer should get their information from the previous process that is the resources with the help of domain expert.

Since domain expert is an expert in particular area, they can help out and guide the knowledge engineer to develop the system. Knowledge engineer helps the domain expert structure the problem area by understanding and incorporating human answers to questions, illustrate analogies, posing contradict examples, and enlightening intangible problems and obstacles. Medical diagnosis responsible for selecting an appropriate task.

After the knowledge engineer done with their task, then proceed to the next step, the expert system or also known as prolog. Prolog is short for programming logic. Prolog was one of the first logical programming languages unlike many other programming languages. It is related with artificial intelligence and computational linguistics. Prolog is declarative, the program logic is expressed in terms of relations, represented as facts and rules. A computation is started by running query over these relations.

Shell is a special purpose tool designed based on the requirements of a particular applications. User should supply the knowledge base to the shell. EMYCIN is one of the shell. Shell manages the input and output. It processes the information given by the user, relates it to concepts contained in the knowledge base, and provides solution for a particular problem.

The advantages of expert systems are it reduces the time or time convenient to the decision making. Expert systems are accessible easily due to accumulation production software. They can be occupied in any unsafe situations where people cannot work with. It responds very quickly to the questions being asked. They usually explain everything precisely the reasoning to led the a conclusion.

However, the disadvantages of expert systems are it is not always readily reliable. It is lack of common sense. The knowledge engineers are unusual and pricey. Expert system is also lack of trust by end-users.

TASK 3: Pass 2.2





High temperature

Runny nose

Sore throat




1- Blood test

2- Temperature check


Name: Adam Brody

Age: 50

Height: 6.0 ft

Weight: 74kg

Gender: Male

Patient's Details


Figure 1.2: Storyboard of

1. Symptoms -  Symptoms are effects, or things that occur, because of something else. They are signs from your body showing there's something wrong. There are many symptoms and on Figure 1.2, I have listed out some of the symptoms.

2. Patient's details - Once the patient check in to the hospital, all of their information need to be input into the database.

3. Tests - Patient must undergo tests such as the blood test and temperature check in order to proceed the treatment.




Sore throat

Runny nose





High temperature

File structure


Disease (Symptom [ ], Disease_name)

Symptom (Symptom [ ], Symptom_name)

Disease (High_temperature, Fever)

Disease (Headache, Fever)

Disease ( Dehydration, Fever)

Symptom (Runny_nose, Flu)

Symptom (Sore_throat, Flu)

Symptom (Fatigue, Flu)

Symptom ( Dizziness, Flu)


? (X, Y) [High_temperature, headache]

X = fever

Y = [Runny_nose,Flu]