人工智能——Chapter03 Logic问题

AI——Logic

Q1：How Agents acquire knowledge?
Agents acquire knowledge through perception, learning, language

• Knowledge of the effects of actions (“transition model”)
• Knowledge of how the world affects sensors (“sensor model”)
• Knowledge of the current state of the world

Q2：Logic contains ?
Logic=Syntax+Semantics
语法+语义

• Syntax: What sentences are allowed?
• Semantics:
  What are the possible worlds?
  Which sentences are true in which worlds? (i.e., definition of truth)
  【几个常见的语义符举例】：
  
  【几个重要的知识点】：
  （1）Knowledge base
  Knowledge base= set of sentences in a formal language
  （2）Example：Analyze the Pacman’s knowledge base
  
• the Knowledge Base of Wall
  Wall_0,0 ∧ Wall_0,1 ∧ Wall_0,2 ∧ Wall_0,3 ∧ Wall_0,4 ∧ Wall_1,4 ∧ …
• the Knowledge Base of Pacman’s location —— Initial state
  At_1,1_0 v At_1,2_0 v At_1,3_0 v At_2,1_0 v …
• the Knowledge Base of sensor model at T=0
  Blocked_W_0 <=> ((At_1,1_0 ∧ Wall_0,1) v
  (At_1,2_0 ∧ Wall_0,2) v
  (At_1,3_0 ∧ Wall_0,3) v …. )
• the transition model for Pacman’s location At_3,3_17
  At_3,3_17 <=> [At_3,3_16 ∧ ⌝((⌝Wall_3,4 ∧ N_16) v (⌝Wall_4,3 ∧ E_16) v …)]
  v [⌝At_3,3_16 ∧ ((At_3,2_16 ∧ ⌝ Wall_3,3 ∧ N_16) v
  (At_2,3_16 ∧ ⌝ Wall_3,3 ∧ E_16) v …)]
  【注意】：
  上述案例是未限制条件的答案，因此展示了所有可能的情况。解答此类型的题目时，需要根据题目前提条件进行分析求解，要在题目已给的条件下进行分析，例如题目已给定Pacman的起始位置，那么the Knowledge Base of Pacman’s location —— Initial state就只有一种情况。