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Smart materials are materials that have one or more properties

that can be significantly changed in a controlled fashion by external stimuli,

such as stress, temperature, moisture, pH, electric or magnetic fields.

IT /

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IT Device

Inter-connection

(2000 )

/ +

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Eudaemonic: Poducing happiness and well-being. /

Existential: .

Constant:

+

EudaemonicExistential

Constant

( , ) ( )

( ) ( )

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: sensor, actuator, processor

- A sensor is a device that measures a physical quantity and converts it into a signal which can be read

by an observer or by an instrument

- An actuator is a mechanical device for moving or controlling a mechanism or system, which takes

energy, usually transported by air, electric current, or liquid, and converts that into some kind of motion.

, ,

e-Textile: , .

- (a)

: ,

,

- (b)

: , , /

- , IT , Inter-connection

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Smart Shirts

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, , , wireless data

Selected by best invention of the year 2001, by Time magazine

Developed by Georgia Tech, and manufactured by Sensatex

Originally funded by US militarys 21 st Centruy Land & Warrior Program

& the Defense Advanced Research Projects Agency

Mass Production (2007) done by Zephyr BioHarness

- NASA, Stanford Medical Center,

US Special OPS for live soldier monitoring

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Dr. Sungmee ParkDr. Sundaresan Jayaraman

Applications of Smart Shirts

Health Monitoring

- (patients in intensive care unit), (SIDS)

- (by Sensatex, 2005)

First responder

- Soldier OPS, Emergency wireless transmission

- (by Sensatex, 2005)

Athletes

- biometric data tracking

: heart rate, respiration rate, body temperature, caloric burning

- wrist watch, PDA, smart phone connection

( , by Zephyr Technology)

Others

- hazardous materials personnel (ex. Nuclear reactor)

- truck driver fatigue

- soldier on the battlefield

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Smart Shirst Wearable Motherboard

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Electronic Textiles Charge Ahead

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A little bit about Conductivity

(electrical conductivity):

J = s * EJ: current densitys : conductivityE: electric field

s = 1 / r r : resistivity

SI unit: S cm -1.

Material Electrical Conductivity ( Sm -1)Silver 63.0 106

Copper 59.6 106

Annealed Copper 58.0 106

Gold 45.2 106

Aluminium 37.8

106

Sea water 4.8Drinking water 0.0005 to 0.05

Deionized water 5.5 10-6

Kerosene 50 to 450 10 -12

n-hexane 100 10 -12

Air 0.3 to 0.8 10 -14

~ 10 7 Sm -1

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A little bit about Conductivity

(electrical resistivity)

r = =

J: current density (A/m 2)

E: electric field (V/m)R: resistance ( W) A: area (m 2)

l : length (m)

EJ Al R

.SI unit: V m/A or W m.

Material Resistivity ( m) at 20 CSilver 1.59 10 8

Copper 1.72 10 8

Gold 2.44 10 8

Constantan 4.9 10 7

Mercury 9.8 10 7

Nichrome 1.10 10 6

Carbon 3.5 10 5

Germanium 4.6 10 1Silicon 6.40 102

Glass 1010 to 10 14

Hard rubber approx. 10 13

Sulfur 1015

Paraffin 1017

Quartz (fused) 7.5 1017

PET 1020

Teflon 1022 to 10 24

: 10 -7 ~ 10 -8 Sm -1: 10 -1 ~ 10 2 Sm -1

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A little bit about Conductivity

Conductivity with temperature

s = q * n * mq: chargen: density of charge carrierm: mobility of charge carrier

- metal: , vibration

mobility

- : , n ( ) m( ) ,

Superconductivity is an electrical resistance of exactly zero which occurs in certain materials

below a characteristic temperature.

The electrical resistivity of a metallic conductor decreases gradually as the temperature is lowered.

However, in ordinary conductors such as copper and silver, this decrease is limited by impurities andother defects. Even near absolute zero, a real sample of copper shows some resistance.

Despite these imperfections, in a superconductor the resistance drops abruptly to zero when the material

is cooled below its critical temperature.

An electric current flowing in a loop of superconducting wire can persist indefinitely with no power source

[Sourced from wikepedia.com]