1. What is sweet
A way brain to interpret information. Illusion from the signal of tongue.
Preference: good source of quick energy as well as essential nutrients
2. Human Color the same
Problem of Qualia
While we can measure the wavelength of light, we can’t objectively measure or compare the internal experience.
So we should use biological and physical bases of things to represent thing
3. Efficient Organization
3.1. Theories
- Economies of Scale. More efficient (cost advantage) once scale
- Diseconomies of Scale. Less efficient due to complexity, communication and bureaucracy
3.2. How to Avoid
- Decentralization
- Flat Organization Structure
- Lean Management
- Outsourcing
3.3. Metrics
Important to set the metrics before discussing what is efficient
- Financial: ROI, Operating Margin, Profit per Employee
- Berkshire Hathaway: diversified investment portfolio
- Operational: Inventory Turnover, cycle time, throughput
- Toyota: great manufacturing
- Human Resource: employee turnover, utilization rate
- Google: selective hiring process, excellent workplace culture
- Quality: Customer Satisfaction, Net promoter, Quality Defect
- Apple: highly
- Tech: downtime, time-to-market, load time
- Amazon
4. How is Mirror Made
Materials:
- Glass substrate
- Metallic coating
- Aluminum: Most common, cost, durability, reflectivity, adhesion, ease of application
- Silver
Steps:
- Prepare a flat glass
- Polishing
- Cleaning
- Coating
- Chemical Vapor Deposition
- Physical Vapor Deposition: Most common, high quality, cost, versatility, speed, environmental
- Sputtering
- Protective coating
- Cutting and Shaping
4.1. PVD
- Metal evaporated in a vacuum chamber
- Metal atoms travel across the chamber and condense on the surface
4.2. Metal Atom?
How to get metal atom?
- Thermal Evaporation
- Sputtering: most commonly used
- Laser Ablation
5. How is Key’s Pattern Generated
5.1. Lock
In traditional lock manufacturing, the lock come first
Core design, determining the number and arrangement
A series of spring-loaded pin:
- key pin
- driver pin
5.2. Key
Blanks are usually mass-produced
Cutting is a highly automated process
5.3. Pair
- Height
- Pin
5.4. Liked Key
Due to the limitation of combination, many lock and key share the same
5.5. Calculation
Two factor
- Number of Pin, typical 5 pins, $n$
- Number of Cut Depth, range from 5-10, $d$
$$
K=d^n
$$
6. Face Clean
Towel? Not exclusive to any particular culture or region
7. What battery car key use, why
Typically CR2032, CR2025, CR2016, lithium type
Why
- Low power requirement
- High energy density
- Stable discharge
- Long Shelf Life
- Low Temperature Operation
8. Car Curb height
Curb height < Ground Clearance
Just a happy accident!
Standard Curbs are between 4-8 inches
Ground clearance of a vehicle is typically based on the intended use.
8.1. Why curb
- Direct rain water into storm drains
- Traffic control, psychological ad physical
- Pedestrian safety