8.7 Artificial Intelligence

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1 Hva er Kunstig intelligens 1 Kunstig intelligens - en kort introduksjon AI = Things that make you go WOW eller?? Agnar Aamodt Institutt for datateknikk og informasjonsvitenskap Gruppe for Intelligente Systemer NTNU Well, somewhat more sober although more dull: AI enables systems to perform tasks in ways that would be called intelligent if done by humans. AI enables complex problem solving and interaction beyond what other (non-ai) methods do. Hva er Kunstig intelligens Artificial Intelligence STUDIET AV INTELLIGENTE SYSTEMER RELATERT PROSESSER TIL KOMPUTASJONELLE MATEMATIKK KOGNITIV har vitenskapelig perspektiv FILOSOFI PSYKOLOGI bygger bl.a. på BIOLOGI INFORMATIKK er delfelt av er koblet via empirisk vitenskapelig metode KUNSTIG INTELLIGENS (AI) har metoder har metoder REALISERING AV DATASYSTEMER SOM KAN SIES Å OPPVISE INTELLIGENT ADFERD - DVS. ' SMARTERE ' SYSTEMER har teknologisk perspektiv SYMBOLORIENTERTE METODER (KUNNSKAPSBASERTE METODER) SUBSYMBOLSKE METODER (BIO-INSPIRERTE METODER) AI is a group of related technologies used to develop software and machines that emulate human qualities such as learning, reasoning, communicating, seeing, and hearing Areas include: Expert systems Natural language processing Intelligent agents Pattern recognition Fuzzy logic Virtual reality and simulation devices Robotics

2 Core idea KUNNSKAPSBASERTE METODER - UTVIKLINGSTRENDER AI = Representation + Search Kontroll-kunnskap The concept of search plays an important role in science and engineering Any problem whatsoever can be seen as a search for the right answer or at least a good answer Heuristiske regler Dyp kunnskap Spesifikke case This search can be viewed to take place in a problem space, which constrains the search through its representation Fra generell kunnskap til situasjons-spesifikke case (f.eks. CYRUS, PROTOS) - case-basert resonnering Hypen rundt A.I. in three to eight years we will have a machine with the general intelligence of an average human being. I mean a machine that will be able to read Shakespeare, grease a car, play office politics, tell a joke, and have a fight. At that point, the machine will start to educate itself with fantastic speed. In a few months it will be at genius level and a few months after that its powers will be incalculable. Marvin Minsky i 1970 KUNNSKAPSBASERTE METODER - er karakterisert ved at kunnskap representeres eksplisitt - modelleres - i form av navngitte begreper og relasjoner mellom disse begreps-termene kalles symboler, da de symboliserer - står for - begreper i den virkelige verden (objekter, hendelser, prosesser,...) symbol-strukturene som derved bygges opp, prosesseres av tolknings- og slutningsmetoder (inferensmetoder) slik at ny informasjon kan utledes, konklusjoner kan trekkes, og ny kunnskap kan læres representasjonen av kunnskapen er adskilt fra metodene som prosesser den - og er kjernemetodene innen kunnskapsteknologi for å utvikle kunnskapsbaserte systemer.

3 KUNNSKAPSBASERTE METODER Representasjon av det som for oss mennesker fortoner seg som kunnskap, i form av symbolstrukturer og inferensmetoder i et datasystem, og på en måte som gjør systemet istand til å tolke symbolene og utifra dette trekke meningsfylte slutninger, gjør at symbolstrukturene kan betraktes som kunnskap for systemet. Dette danner basis for det 'kunnskapsbaserte paradigmet' innen AI, og for rekken av kunnskapsbaserte systemer som er utviklet og i daglig bruk. Refereres ofte til som GOFAI Good Old-Fashioned AI,for å skille denne typen metoder fra ikke-symbolske, eller sub-symbolske tilnærminger til AI. Fuzzy Logic Reasoning A computer chess success Everything is matter of degree Critical Serious Minor Uninjured 1.0 Kunnskap beskrives som regler som det gjøres Fuzzy reasoning på: Near Death 0.0 Health If (range is Melee AND health is Uninjured) AND rating is NOT Hard THEN action is Attack If ( range is NOT Melee AND health is Uninjured) THEN action is Donothing If (range is Melee AND health is NOT Uninjured) AND rating is NOT Wimp THEN action is Flee Easy 1.0 Hard Wimp 0.0 qualitative description used in everyday language Moderate Rating

4 A Jeopardy success: Watson En kritikk av kunnskapsbaserte metoder Mennesker representerer sin kunnskap i maskinen, den kan defor ikke bli maskinens. Nyttig kritikk, men satt på spissen. Berører kunnskapsrepresentasjons-problemet generelt. - Konsekvenser for interaktive rådgivingssystemer : Utviklingsmetoder der mindre vekt legges på datamaskinen som problemløser, mer på samspillet mellom maskin og bruker. En utfordring er at systemet må ha eller bygge opp kunnskap om interaksjons-omgivelsen. - Konsekvenser for maskinlæring : Større grad av erfaringsbasert læring, der systemene lærer gradvis ved å delta i løsningen av reelle problemer i det miljø de virker. For (morgen)dagens ekspertsystemer : Fra 'tradisjonelle' problemløsende systemer til aktive, interaktive, og adaptive beslutningsstøtte-systemer Nevrale Nett Biologisk bakgrunn: Et nettverk av nerveceller SUBSYMBOLSKE METODER (eks.) NEVRALE NETT Cell body Distribuert representasjon i et nettverk av noder koblet sammen via lenker (konneksjonisme). Ingen eksplisitt begreper, direkte representasjon av sammenhenger. GENETISKE ALGORITMER Representasjon i form av bit-strenger som maniplueres vha. genetiske operatorer. Bit-strengene kan representere begreper, men ikke nødvendigvis.

5 Bio-inspired methods Swarm Intelligence The signal feature of life is not the carbon-based substrate...(but)...that the local dynamics of a set of interacting entities (e.g. molecules, cells, etc.) supports an emergent set of global dynamical structures which stabilize themselves by setting the boundary conditions within which the local dynamics operates (Charles Taylor, biologist, UCLA) Follow Trail Find Food Make Trail Darwinian Evolution Evolutionary Algorithms Phenotypes Physiological, Behavioral Natural Selection Ptypes Parameters, Code, Neural Nets, Rules Semantic Performance Test P,C,N,R Morphogenesis Reproduction Sex Translate R &M Generate Genotypes Recombination & Mutation Gtypes Bit Strings Recombination & Mutation Bits Genetic Syntactic

6 8.7 Artificial Intelligence Turing-testen" Turing Test In 1950 Allen Turing predicted computers would eventually be able to mimic human thinking Turing test determines whether the computer is human Judge is in another location and doesn t see the computer Judge converses via a computer terminal with two entities: one a person and one a computer Judge must determine who is the person and who the computer If the computer can fool the judge, it is said to be intelligent No computer system has yet passed the Turing test

7 8.7 Artificial Intelligence 8.7 Artificial Intelligence Weak vs. Strong AI Weak AI Computers can be programmed to simulate human cognition Strong AI Computers can think on a level that is equal to or better than humans and can also achieve consciousness Strong AI Cyc approach to strong AI A database in Austin, TX that holds about 1.4 million basic truths Plan is that Cyc will automatically make human-like assumptions Hope is that Cyc will learn on its own Cog approach to strong AI MIT project that is a humanoid robot with sensory systems Tries to identify and search for patterns instead of following rules and facts 8.7 Artificial Intelligence Smarter-Than-Human Computers The Singularity A moment when humans would have created self-aware, smarter-than-human machines capable of designing computers and robots that are better than humans can design today Also may involve transferring the contents of human brains and thought processes into a computing environment 8.7 Artificial Intelligence Ethics in A.I. Computer software is subtly shaped by the ethical judgments and assumptions of its creators. Will humans lose control of computer systems? There is no such thing as completely value-free technology.

8 NTNU Eksempler på aktiviteter NTNU Bilde- og/eller Video-analyse (Her: Segmentere bilder av fisk i Mauritius) Improved game AI through case-based and statistical reasoning

9 Intelligent Hardware Robots (pictured) that interact with either a real or simulated other robot. Within our PUCKER system, researchers and students can easily test their AI control strategies on this type of robot (epucks). Today s hardware technologies, especially Field programmable Gate Arrays (FPGAs), provide many possibilities for the creation of intelligent Hardware - that is AI techniques embedded in hardware. Such embedding may be for the purpose of speed-up of a given AI technique for perhaps real-time application requirements or for the purpose of creating hardware circuits, applying bioinspired techniques as the design technique. The latter is known as the field of Evolvable Hardware and includes applications in today s technology and approaches to achieve computation in tomorrow s technology. Application areas range from Vision, art to electronic circuits. Språkteknologi - maskinoversetting

10 Textual CBR. Data mining and Decision support in Fish Farming Discovery of causal relations in incident reports An incident report (i.e., a 'textual case') describes how a problem unfolds. That is, the story starts with less important 'symptoms'/evidence which, in turn, triggers/causes more serious ones, and this chain of evidence ends up with an undesired, anomalous event. It is important to identify the events when they are small, and discover the causal mechanisms underlying the chain of events. Use of eye-tracking in the selection of important features in a text and determining how important they are - the latter is called 'weighting. This in cooperation with people at Dragvoll. Reducing unwanted downtime in oil drilling One day of unwanted downtime on this rig means increased cost of 1,6 MNOK for the ongoing drilling operation. Providing the relevant experience and getting the right information precisely when needed will reduce unwanted operational downtime. The result is a more reliable drilling process, reduced drilling costs, and increased productivity. IDIs AI-gruppe har deltatt i etablering av tre spin-off selskaper: - LingIT AS - naturlig språk tolkning og dialogsystemer - Trollhetta AS - bildeanalyse og beslutningsstøtte - Verdande Technology AS - erfarings-lagring og aktiv gjenbruk, primært innen oljeboring

11 Artificial Intelligence (AI) - represents a set of computer science methods aimed at intelligent behaviour of computer systems - covers a lot of methods and application areas - is interesting, useful, and fun A useful link to all of AI: