Elevation gaining effect on walking speed

[Ricard Diago Sambuaga]

Hey, I am quiet new in netlogo environment. Currently , I would like to make a evacuation model that the walking speed is affected by gaining elevation. I know how to input these environments dataset, such as: DEM, road network, population density, etc. i do not know how to eloborate the code to make the walking speed is affected by elevation (gaining elevation, walking speed is slower and etc.)

Do you have any idea, what should i do with this issue? or Do you have any kind of references or sample code, etc that might help me with this problems?

Thank you for your support
Best regards

[Dale Frakes]

Assuming you have elevation coded as a patch variable, and walking speed as a turtle variable, you could add a section to your "go" code that asks each turtle to calculate their walking speed based on the elevation of the patch they're on. 

If you were to say their walking speed = 10 / elevation, that might look like:


patches-own [
  elevation
]

turtles-own [
  walking-speed
]

to setup
  clear-all
  reset-ticks
 
  create-turtles 100 [
    setxy random-xcor random-ycor
  ]
 
  ask patches [
    set elevation random-float 10 + 1 ;; random for this example
  ]
 
end

to go
  ask turtles [
    set walking-speed elevation / 10
    forward walking-speed
  ]
 
  tick
 
end


You'd probably need to come up with something more reasonable for that formula, but that's the main idea.  Then elsewhere in your "go" code, you'd somehow use their walking-speed to determine how far they move.

Cheers!

Dale

-- 
Dale Frakes
Adjunct Instructor, PhD Candidate
PSU Systems Science
dfr...@pdx.edu - http://web.pdx.edu/~dfrakes/

[Ricard Diago Sambuaga]

Dear Mr. Dale Frakes

Thank you for your respond.

Currently I am using this code for "go" instruction. 

Probably I would like to use this code to load raster (elevation datasets). 

Would you please help me regarding to this issue?

Thank you

Best regards

to display-elevation

gis:apply-raster elevation-dataset elevation

  let max-elevation gis:maximum-of elevation-dataset

  ask patches [

    if (elevation >= -111.97) and (elevation < 441.37) [ set pcolor (approximate-rgb 56 168 0)]

    if (elevation >= 441.38) and (elevation < 1627.08) [ set pcolor (approximate-rgb 90 186 0)]

    if (elevation >= 1627.09) and (elevation < 3366.12) [ set pcolor (approximate-rgb 131 207 0)]

    if (elevation >= 3366.13) and (elevation < 5105.16) [ set pcolor (approximate-rgb 176 224 0)]

    if (elevation >= 5105.17) and (elevation < 6923.25) [ set pcolor (approximate-rgb 228 245 0)]

    if (elevation >= 6923.26) and (elevation < 8820.38) [ set pcolor (approximate-rgb 225 225 0)]

    if (elevation >= 8820.39) and (elevation < 10875.61) [ set pcolor (approximate-rgb 255 170 0)]

    if (elevation >= 10875.62) and (elevation < 13247.03) [ set pcolor (approximate-rgb 255 115 0)]

    if (elevation >= 13247.04) and (elevation < 15855.59) [ set pcolor (approximate-rgb 255 55 0)]

    if (elevation >= 15855.6) and (elevation < max-elevation) [ set pcolor (approximate-rgb 255 0 0)]

  ]

end

to go

  if ticks >= int(3600 / tick_to_sec) [stop]                ; stop after simulating an hour

  ; update the tsunami depth every 30 seconds

  if int(ticks * tick_to_sec) mod 30 = 0 [

    ask patches with [depths != 0][

      set depth item int(ticks * tick_to_sec / 30) depths   ; set the depth to the correct item of depths list (depending on the time)

      if depth > max_depth [                                ; monitor the maximum depth observed at each patch, for future use.

        set max_depth depth

      ]

    ]

    ; recolor the patches based on the tsunami depth, the deeper the darker the shade of blue

    ask patches [

      let cl 99.9 - depth

      if cl < 90 [set cl 90]

      if cl > 99.9 [set cl 99.9]

      set pcolor cl

    ]

  ]

  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;

  ;;;;;;;;; RESIDENTS ;;;;;;;;

  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;

  ; ask residents, if they milling time has passed, to start moving

  ask residents with [not moving? and not dead? and miltime <= ticks][

    set heading towards init_dest

    set moving? true

  ]

  ; ask residents that should be moving to move

  ask residents with [moving?][

    ifelse (distance init_dest < (speed) ) [fd distance init_dest][fd speed]

    if distance init_dest < 0.005 [   ; if close enough to the next intersection, move the agent to it

      move-to init_dest

      set moving? false

      set reached? true

      set current_int init_dest

    ]

  ]

  ; check the residnet that are on the way if they have been caught by the tsunami

  ask residents with [not reached?][

    if [depth] of patch-here > Hc [mark-dead]

  ]

  ; ask residets who have reached the network to hatch into a pedestrian or a car depending on their decision

  ask residents with [reached?][

    let spd speed                ; to pass on the spd from resident to the hatched pedestrian

    let dcsn decision            ; to pass on the decision from the resident to either car or pedestrian

    if dcsn = 1 or dcsn = 3 [    ; horizontal (1) or vertical (3) evacuation - by FOOT

      ask current_int [          ; ask the current intersection of the resident to hatch a pedestrian

        hatch-pedestrians 1 [

          set size 1

          set shape "dot"

          set current_int myself ; myself = current_int of the resident

          set speed spd          ; the speed of the resident is passed on to the pedestrian

          set evacuated? false   ; initialized as not evacuated, will be checked immediately after being born

          set dead? false        ; initialized as not dead, will be checked immediately after being born

          set moving? false      ; initialized as not moving, will start moving immediately after if not evacuated and not dead

          if dcsn = 1 [          ; horizontal evacuation on foot

            set color orange

            set path [hor-path] of myself ; myself = current_int of the resident - Note that intersection hold the path infomration

                                          ; which passed to the pedestrians and cars

            set decision 1

          ]

          if dcsn = 3 [          ; vertical evacuation on foot

            set color turquoise

            set path [ver-path] of myself ; myself = current_int of the resident - Note that intersection hold the path infomration

                                          ; which passed to the pedestrians and cars

            set decision 3

          ]

          ifelse empty? path [set shelter -1][set shelter last path] ; if path list is not empty the who of the shelter is the last item of the path

                                                                     ; otherwise, there is no shelter destination, either the current_int is the shelter

                                                                     ; or due to network disconnectivity, there were no path available to any of the shelters

          if shelter = -1 [

            if decision = 1 and [shelter_type] of current_int = "Hor" [set shelter -99]  ; if the decision is horizontal evac and the list is empty since current_int is a horizontal shelter

            if decision = 3 and [shelter?] of current_int [set shelter -99]              ; if the decision is vertical evac and the list is empty since current_int is a shelter

                                                                                         ; basically if shelter = -99, we can mark the pedestrian as evacuated later

          ]

          st

        ]

      ]

    ]

    if dcsn = 2 or dcsn = 4 [   ; horizontal (2) or vertical (4) evacuation - by CAR

      ask current_int [         ; ask the current intersection of the resident to hatch a car

        hatch-cars 1 [

          set size 1

          set current_int myself ; myself = current_int of the resident

          set evacuated? false   ; initialized as not evacuated, will be checked immediately after being born

          set dead? false        ; initialized as not dead, will be checked immediately after being born

          set moving? false      ; initialized as not moving, will start moving immediately after if not evacuated and not dead

          if dcsn = 2 [          ; horizontal evacuation by car

            set color sky

            set path [hor-path] of myself ; myself = current_int of the resident

            set decision 2

          ]

          if dcsn = 4 [          ; vertical evacuation by car

            set color magenta

            set path [ver-path] of myself ; myself = current_int of the resident

            set decision 4

          ]

          ifelse empty? path [set shelter -1][set shelter last path]       ; if path list is not empty the who of the shelter is the last item of the path

          if shelter = -1 [

            if decision = 2 and [shelter_type] of current_int = "Hor" [set shelter -99] ; if the decision is horizontal evac and the list is empty since current_int is a horizontal shelter

            if decision = 4 and [shelter?] of current_int [set shelter -99]             ; if the decision is vertical evac and the list is empty since current_int is a shelter

                                                                                        ; basically if shelter = -99, we can mark the car as evacuated later

          ]

          st

        ]

      ]

    ]

    die

  ]

  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;

  ;;;;;;; PEDESTRIANS ;;;;;;;;

  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;

  ; check the pedestrians if they have evacuated already or died

  ask pedestrians with [not evacuated? and not dead?][

    if [who] of current_int = shelter or shelter = -99 [mark-evacuated]

    if [depth] of patch-here >= Hc [mark-dead]

  ]

  ; set up the pedestrians that should move

  ask pedestrians with [not moving? and not empty? path and not evacuated? and not dead?][

    set next_int intersection item 0 path   ; assign item 0 of path to next_int

    set path remove-item 0 path             ; remove item 0 of path

    set heading towards next_int            ; set the heading towards the destination

    set moving? true

    ask road ([who] of current_int) ([who] of next_int)[set crowd crowd + 1] ; add the crowd of the road the pedestrian will be on

  ]

  ; move the pedestrians that should move

  ask pedestrians with [moving?][

    ifelse speed > distance next_int [fd distance next_int][fd speed] ; move the pedestrian towards the next intersection

    if (distance next_int < 0.005 ) [                                 ; if close enough check if evacuated? dead? if neither, get ready for the next step

      set moving? false

      ask road ([who] of current_int) ([who] of next_int)[set crowd crowd - 1] ; decrease the crowd of the road the pedestrian was on

      set current_int next_int                                                 ; update current intersection

      if [who] of current_int = shelter [mark-evacuated]

      if [depth] of patch-here >= Hc and not evacuated? [mark-dead]

    ]

  ]

  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;

  ;;;;;;;;;;; CARS ;;;;;;;;;;;

  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;

  ; check the cars if they have evacuated already or died

  ask cars with [not evacuated? and not dead?][

    if [who] of current_int = shelter or shelter = -99 [mark-evacuated]

    if [depth] of patch-here >= Hc [mark-dead]

  ]

  ; set up the cars that should move

  ask cars with [not moving? and not empty? path and not evacuated? and not dead?][

    set next_int intersection item 0 path   ; assign item 0 of path to next_int

    set path remove-item 0 path             ; remove item 0 of path

    set heading towards next_int            ; set the heading towards the destination

    set moving? true

    ask road ([who] of current_int) ([who] of next_int)[set traffic traffic + 1] ; add the traffic of the road the car will be on

  ]

  ; move the cars that should move

  ask cars with [moving?][

    move-gm                 ; set the speed with general motors car-following model

    fd speed                ; move

    if (distance next_int < 0.005 ) [    ; if close enough check if evacuated? dead? if neither, get ready for the next step

      set moving? false

      ask road ([who] of current_int) ([who] of next_int)[set traffic traffic - 1] ; decrease the traffic of the road the pedestrian was on

      set current_int next_int           ; update current intersection

      if [who] of current_int = shelter [mark-evacuated]

      if [depth] of patch-here >= Hc and not evacuated? [mark-dead]

    ]

  ]

  tick

end