CS代考计算机代写 AI PowerPoint Presentation

PowerPoint Presentation

Semantic Networks

Semantic Networks
Generate and Test
Problem Reduction
Means-Ends Analysis
Fundamentals
Production Systems

Lesson Preview

Knowledge representations

Semantic networks

Problem-solving with semantic networks

Represent & Reason

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The relationships between the pieces and the transformations between the frames.

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Structure of Semantic Networks

Lexically: nodes

Structurally: directional links

Semantically: application-specific labels
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Characteristics of Good Representations

Make relationships explicit

Expose natural constraints

Bring objects and relations together

Exclude extraneous details

Transparent, concise, complete, fast, computable

Guards & Prisoners Problem

Also known by other names (cannibals and missionaries, jealous husbands, brothers and sisters).

Originally appeared in the 1200-year-old text Propositiones ad Acuendos Juvenes.

Used by throughout AI for problem representation.

Guards & Prisoners Problem

Three guards and three prisoners must cross river.

Boat may take only one or two people at a time.

Prisoners may never outnumber guards on either coast, though prisoners may be alone on either coast).



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Exercise: How many moves does it take to move everyone to the other side?
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Is this the right answer to the problem? ο Yes ο No
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Transformation #1

Transformation #2
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Similarity Weights
5 points Unchanged
4 points Reflected
3 points Rotated
2 points Scaled
1 points Deleted
0 points Shape Changed

Similarity:
6 points
Similarity:
3 points

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Similarity Weights
5 points Unchanged
4 points Reflected
3 points Rotated
2 points Scaled
1 points Deleted
0 points Shape Changed

Assignment

How would you use semantic networks to design an agent that can answer Raven’s Progressive Matrices?

To recap…

Representations

Semantic networks

Represent & Reason

Weights with Represent & Reason

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What is the answer to this problem?

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What is the answer to this problem?

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Horizontal Reflection
180° Rotation

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180° Rotation

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What would the answer be? ο 2 ο 6

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