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Transportation networks have analogs with network processes in other systems, such as water networks, structures, and electrical networks. Some of the relationships are outlined below.
| ' |
Transportation |
Water: Hydrostatics |
Structures |
Electrical |
| Node Conservation Law |
Flow (q) |
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Current (Kirchoff’s Current Law) |
| Fundamental Law |
q = kv |
P = ρgh |
F=δ (mv)/ δ (T) |
V=IR |
|
k = q/v |
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F= v δ (m)/ δ (T) |
V=I/G |
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v=q/k |
Bernoulli’s Equation: |
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Ohm’s Law on resistor |
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Constant=p+1/2ρ V2+ ρgh |
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P=F/A (area) |
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F=ma |
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| Analogs |
flow (q) |
Pressure (P*A) |
δm/δT |
Current (I) |
|
density (k) |
Density (ρ) |
Force (F) |
Voltage (V) |
|
velocity (v) |
velocity (v) |
velocity |
Conductance (G) |
| Equilibrium Conditions |
Wardrop (time equal on used pairs in parallel) |
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Sum of horizontal (and sum of vertical) forces on a structure = 0, sum of moments = 0. |
Voltage drop across two components in parallel are equal |
[edit] Structures
- F= force
- m = Mass
- a = acceleration
- T = Time
[edit] Transportation
- q = flow
- k = density
- v = velocity
[edit] Electricity
- V= Voltage
- I = Current
- R = Resistance
- G = Conductance = 1 / Resistance
- P = hydrostatic pressure
- ρ = fluid density =mV = mass *volume
- g = acceleration due to gravity
- h = height
- c= constant
- A = area
