# Printer Ontology

## Overview

Ontology mô tả quan hệ logic giữa các thực thể trong hệ thống máy in.

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## Entity Relationships

### Manufacturer → Series

HP → LaserJet

Canon → LBP

Brother → HL

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### Series → Model

LaserJet → M404dn

LBP → LBP2900

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### Model → Cartridge

M404dn → CF259A

LBP2900 → Cartridge 303

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### Model → Parts

Model → Pickup Roller

Model → Fuser Unit

Model → Drum Unit

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### Model → Error

Model → Paper Jam

Model → Toner Low

Model → Print Blank Page

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### Error → Procedure

Paper Jam → Paper Feed Cleaning Procedure

Toner Low → Refill Toner Procedure

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### Procedure → Service

Procedure → On-site Repair Service

Procedure → Maintenance Service

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## Design Goal

- Quan hệ hai chiều (bidirectional)
- Hỗ trợ graph traversal
- Tối ưu RAG context expansion