3. Phẩm chất cục bộ

Nguyên tắc con

1. Replace a uniform structure with one that differs from region to region
2. Let each region of the object take a different function
3. Place each region in the conditions best suited to its role

Ví dụ

• A tool with a non-slip rubber grip only where the hand goes
• A running-shoe sole whose cushioning density varies by zone
• A refrigerator that keeps each compartment at its own temperature

Ứng dụng theo lĩnh vực

• mechanical: A gear hardened all through cracks under shock, and a soft one wears its teeth quickly. Hardening only the tooth surface and leaving the core tough resists both wear and shock.
• electronics: Cooling a whole phone evenly would make it heavy and thick. Heat-spreading sheets and metal plates go only around the hottest chip, and the rest stays light.
• software: Keeping all data in fast memory is costly, and keeping it all on cheap storage is slow. Frequently used data stays in fast memory while rarely used data moves to cheap storage.
• medical: A dressing made of one material sticks to the wound and peels off at the edges. A non-stick pad in the middle over the wound and an adhesive border give each region its own job.