UNIT-1 INTRODUCTION TO ARTIFICIAL INTELLIGENCE Artificial Intelligence Definition: Artificial + intelligence = non natural = ability to understand learn & think. “The science and engineering of making intelligent machines, especially intelligent computer programs”. It is a developing techniques and tools to solve the problem. Artificial Intelligence is a way of making a computer, a computer-controlled robot, or a software think intelligently, in the similar manner the intelligent humans think. Goals of AI: To Create Expert Systems − The systems which exhibit intelligent behavior, learn, demonstrate, explain, and advice its users. To Implement Human Intelligence in Machines − Creating systems that understand, think, learn, and behave like humans. Artificial intelligence is a science and technology based on disciplines such as Computer Science, Biology, Psychology, Linguistics, Mathematics, and Engineering. A major thrust of AI is in the development of computer functions associated with human intelligence, such as reasoning, learning, and problem solving. Out of the following areas, one or multiple areas can contribute to build an intelligent system. Programming Without and With AI: The programming without and with AI is different in following ways − Programming Without AI Programming With AI A computer program without AI can answer the specific questions it is meant to solve. A computer program with AI can answer the generic questions it is meant to solve.
Modification in the program leads to change in its structure. AI programs can absorb new modifications by putting highly independent pieces of information together. Hence you can modify even a minute piece of information of program without affecting its structure. Modification is not quick and easy. It may lead to affecting the program adversely. Quick and Easy program modification. AI Techniques: In the real world, the knowledge has some unwelcomed properties − Its volume is huge, next to unimaginable. It is not well-organized or well-formatted. It keeps changing constantly. AI Technique is a manner to organize and use the knowledge efficiently in such a way that − It should be perceivable by the people who provide it. It should be easily modifiable to correct errors. It should be useful in many situations though it is incomplete or inaccurate. AI techniques elevate the speed of execution of the complex program it is equipped with. Applications of AI: AI has been dominant in various fields such as − Gaming − AI plays crucial role in strategic games such as chess, poker, tic-tac-toe, etc., where machine can think of large number of possible positions based on heuristic knowledge. Natural Language Processing − It is possible to interact with the computer that understands natural language spoken by humans. Expert Systems − There are some applications which integrate machine, software, and special information to impart reasoning and advising. They provide explanation and advice to the users. Vision Systems − These systems understand, interpret, and comprehend visual input on the computer. For example, 1. A spying aeroplane takes photographs, which are used to figure out spatial information or map of the areas. 2. Doctors use clinical expert system to diagnose the patient. 3. Police use computer software that can recognize the face of criminal with the stored portrait made by forensic artist.
Speech Recognition − Some intelligent systems are capable of hearing and comprehending the language in terms of sentences and their meanings while a human talks to it. It can handle different accents, slang words, noise in the background, change in human’s noise due to cold, etc. Handwriting Recognition − The handwriting recognition software reads the text written on paper by a pen or on screen by a stylus. It can recognize the shapes of the letters and convert it into editable text. Intelligent Robots − Robots are able to perform the tasks given by a human. They have sensors to detect physical data from the real world such as light, heat, temperature, movement, sound, bump, and pressure. Defining the problem as a state space search: The steps that are required to build a system to solve a particular problem are: 1. Problem Definition that must include precise specifications of what the initial situation will be as well as what final situations constitute acceptable solutions to the problem. 2. Problem Analysis , this can have immense impact on the appropriateness of varies possible techniques for solving the problem. 3. Selection of the best technique(s) for solving the particular problem. Suppose we have a water jug problem: You are given two jugs , a 4- gallon one and a 3- gallon one .Neither has any measuring markers on it . There is a pump that can be used to fill the jugs with water how can you get exact 2 gallons of water into the 4- gallon jug? The state space for this problem can be described as of ordered pairs of integers (x, y) , such that x=0,1,2,3 or 4 and y=0,1,2 or 3 , represents the number of gallons of water in the 4gallon jug , and y represents the quantity of water in the 3- gallon jug . The start state is (0,0) . The goal state is (2,n) for any value of n ( since the problem does not specify how many gallons need to be in the 3- gallon jug). The operators to be used to solve the problem can be described as shown in Fig bellow. They are represented as rules whose left side are matched against the current state and whose right sides describe the new state that results from applying the rule. 1- (x,y) (4,y) fill the 4- gallon jug If x<4 2- (x,y) (x,3) fill the 3-gallon jug If x<3 3- (x,y) (x-d,y) pour some water out of the 4- gallon jug If x>0 4- (x,y) (x-d,y) pour some water out of the 3- gallon jug If y>0 5-(x,y) (0,y) empty the 4- gallon jug on the ground If x>0 6-(x,y) (x,0) empty the 3- gallon jug on the ground If y>0 7- (x,y) (4,y-(4-x)) pour water from the 3- gallon jug into the 4-gallon ,If x+y>=4 and y>0 jug until the 4-galoon jug is full 8- (x,y) (x-(3-y),3)) pour water from the 4- gallon jug into the 3-gallon ,If x+y>=3 and x>0 jug until the 3-gallon jug is full
9- (x,y) gallon jug (x+y,0) pour all the water from the 3 -gallon jug into, If x+y<=4 and y>0 the 3- 10- (x,y) gallon jug (0,x+y) pour all the water from the 4 -gallon jug into,ifx+y<=3 and x>0 the 3- 11- (0,2) (2,0) pour the 2-gallon from the 3 -gallon jug into the 4-gallon jug 12- (2,y) (0,x) empty the 2 gallon in the 4 gallon on the ground Production for the water jug problem: Gallons in the 4- gallon Jug Gallons in the Rule Applied 3- gallon 0 0 0 3 2 3 0 9 3 3 2 4 2 7 0 2 5 or 12 2 0 9 or 11 One solution to the water Jug problem.