diff --git a/description.lua b/description.lua
index 991dbb9..25d5fbd 100644
--- a/description.lua
+++ b/description.lua
@@ -1,6 +1,7 @@
-version = "0.3"
+version = "0.4"
 license = "GPL"
 package = "sysdyn"
+depends = "terrame (>= 1.6), sci (>= 0.1)"
 title = "System Dynamics"
 authors = "Gilberto Camara and Pedro R. Andrade"
 contact = "pedro.andrade@inpe.br"
diff --git a/load.lua b/load.lua
old mode 100755
new mode 100644
diff --git a/lua/ChaoticGrowth.lua b/lua/ChaoticGrowth.lua
index c266d97..7b478a4 100644
--- a/lua/ChaoticGrowth.lua
+++ b/lua/ChaoticGrowth.lua
@@ -2,7 +2,13 @@
 --- A Model that describes a chaotic population growth.
 -- @arg data.pop The initial population. The default value is 0.1.
 -- @arg data.rate The rate that multiplies the population size in each time step. The degault value is 4.
+-- @arg data.deltaTime A numeric value with the period to execute the changes of
+-- the model. The default value is one.
+-- @arg data.updateTime A numeric value with the period to update the charts.
+-- The default value is one.
 -- @arg data.finalTime The final time of the simulation. The default value is 300.
+-- @arg data.view A table with two boolean elements, timeSeries and cobWeb (default true),
+-- indicating whether a time series charts should be drawn.
 -- @image chaotic-growth.bmp
 ChaoticGrowth = SysDynModel{
 	pop       = 0.10,
diff --git a/lua/Homeostasis.lua b/lua/Homeostasis.lua
index 6909d9e..4e6f9ba 100644
--- a/lua/Homeostasis.lua
+++ b/lua/Homeostasis.lua
@@ -1,8 +1,15 @@
 
 --- A model to show homeostasis taking place.
+-- @arg data.stock The initial stock. The default value is 0.
 -- @arg data.gain The fixed increment in the stock in each time step. The default value is 2.0.
 -- @arg data.rate The rate that multiplies the stock in each time step. The default value is -0.4.
 -- @arg data.finalTime The final time of the simulation. The default value is 30.
+-- @arg data.deltaTime A numeric value with the period to execute the changes of
+-- the model. The default value is one.
+-- @arg data.updateTime A numeric value with the period to update the charts.
+-- The default value is one.
+-- @arg data.view A table with a boolean element timeSeries (default true) indicating whether
+-- a time series chart should be drawn.
 -- @image homeostasis.bmp
 Homeostasis = SysDynModel{
 	stock = Choice{0.0, 2.0, 4.0, 10.0, 100.0},
diff --git a/lua/LimitedGrowth.lua b/lua/LimitedGrowth.lua
index 0477aab..29cd644 100644
--- a/lua/LimitedGrowth.lua
+++ b/lua/LimitedGrowth.lua
@@ -4,6 +4,12 @@
 -- @arg data.rate The growth rate of the population.
 -- @arg data.capacity The maximum amount of individuals.
 -- @arg data.finalTime The number of simulation steps.
+-- @arg data.deltaTime A numeric value with the period to execute the changes of
+-- the model. The default value is one.
+-- @arg data.updateTime A numeric value with the period to update the charts.
+-- The default value is one.
+-- @arg data.view A table with a boolean element timeSeries (default true) indicating whether
+-- a time series chart should be drawn.
 -- @image limited-growth.bmp
 LimitedGrowth = SysDynModel{ 
 	pop    = 300,
diff --git a/lua/MonoLake.lua b/lua/MonoLake.lua
index 7e60bb0..2f63826 100644
--- a/lua/MonoLake.lua
+++ b/lua/MonoLake.lua
@@ -51,11 +51,17 @@ end
 -- @arg data.otherIn Other inputs of water to the lake in KAF/year.
 -- @arg data.evapRate The evaporation rate in feet/year.
 -- @arg data.otherOut Other output of water from the lake in KAF/year.
+-- @arg data.deltaTime A numeric value with the period to execute the changes of
+-- the model. The default value is one.
+-- @arg data.updateTime A numeric value with the period to update the charts.
+-- The default value is one.
+-- @arg data.finalTime The final time of the simulation. The default value is 50.
+-- @arg data.view A table with a boolean element timeSeries (default true) indicating whether
+-- a time series chart should be drawn.
 -- @image monolake.bmp
 MonoLake = SysDynModel {
 	waterInLake   = 2228.0,  -- kiloAcre * feet 
 	level         = 6224,
-	surf          = 0.0,
 	-- input
 	precRate      = 0.67,    -- feet/year
 	runoff        = 150,     -- KAF/year
@@ -74,6 +80,6 @@ MonoLake = SysDynModel {
 		model.level = waterElevation:value(model.waterInLake)
 	end,
 
-	graphics = { timeseries =  { {"level"}, {"waterInLake" }}}
+	graphics = {timeseries = {{"level"}, {"waterInLake"}}}
 }
 
diff --git a/lua/PopulationGrowth.lua b/lua/PopulationGrowth.lua
index cef6a18..e5c8cc0 100644
--- a/lua/PopulationGrowth.lua
+++ b/lua/PopulationGrowth.lua
@@ -9,6 +9,12 @@
 -- @arg data.growthChange The change of the growth rate. The growth
 -- rate is multiplied by this value in each time step.
 -- @arg data.finalTime The final time of the simulation. The default value is 100.
+-- @arg data.deltaTime A numeric value with the period to execute the changes of
+-- the model. The default value is one.
+-- @arg data.updateTime A numeric value with the period to update the charts.
+-- The default value is one.
+-- @arg data.view A table with a boolean element timeSeries (default true) indicating whether
+-- a time series chart should be drawn.
 -- @image population-growth.bmp
 PopulationGrowth = SysDynModel{
 	population1 = 60,
diff --git a/lua/PredatorPrey.lua b/lua/PredatorPrey.lua
index 5d4bf15..d2239d2 100644
--- a/lua/PredatorPrey.lua
+++ b/lua/PredatorPrey.lua
@@ -10,8 +10,14 @@
 -- to die. The default value is 0.02.
 -- @arg data.predGrowthKills A number between 0 and 0.01 with the increase in the size of the
 -- predator population per eack prey killed. The default value is 0.00002.
+-- @arg data.deltaTime A numeric value with the period to execute the changes of
+-- the model. The default value is one.
+-- @arg data.updateTime A numeric value with the period to update the charts.
+-- The default value is one.
 -- @arg data.finalTime The final time of the simulation. The minimum value is 50 and the
 -- default value is 500.
+-- @arg data.view A table with two boolean elements, timeSeries and phaseSpace (default true),
+-- indicating whether a time series charts should be drawn.
 -- @image predator-prey.bmp
 PredatorPrey = SysDynModel{
 	wolves          = Choice{min = 10,                 default = 40},
diff --git a/lua/RandomWalk.lua b/lua/RandomWalk.lua
index 906397e..ae935cd 100644
--- a/lua/RandomWalk.lua
+++ b/lua/RandomWalk.lua
@@ -6,6 +6,12 @@
 -- time step. The available values are 0, 0.3, 0.5 (default), 0.7, 0.95, and 1.
 -- @arg data.finalTime The final time of the simulation. It should be
 -- at least 10. The default value is 100.
+-- @arg data.deltaTime A numeric value with the period to execute the changes of
+-- the model. The default value is one.
+-- @arg data.updateTime A numeric value with the period to update the charts.
+-- The default value is one.
+-- @arg data.view A table with a boolean element timeSeries (default true) indicating whether
+-- a time series chart should be drawn.
 -- @image random-walk.bmp
 RandomWalk = SysDynModel{
 	value = 0,   -- initial condition
diff --git a/lua/RoomTemperature.lua b/lua/RoomTemperature.lua
old mode 100755
new mode 100644
index 245bba0..0ee72ef
--- a/lua/RoomTemperature.lua
+++ b/lua/RoomTemperature.lua
@@ -5,23 +5,36 @@
 -- @arg data.temperature3 The initial temperature of the third room. The default value is 5.
 -- @arg data.exterior The temperature outside the rooms. The default value is 20.
 -- @arg data.finalTime The final time of the simulation. The default value is 100.
+-- @arg data.deltaTime A numeric value with the period to execute the changes of
+-- the model. The default value is one.
+-- @arg data.updateTime A numeric value with the period to update the charts.
+-- The default value is one.
+-- @arg data.outside The temperature outside the room. The default value is 1.
+-- @arg data.inside The temperature inside the room. The default initial value is 15.
+-- @arg data.tempSet The selected temperature in the thermostat. The default value is 20.
+-- @arg data.lossToOutside The percentage of heat loss every time step according to the
+-- difference between the temperature inside and outside the room. The default value is 0.3.
+-- @arg data.thermalInertia The percentage of input heat every time step according to the
+-- difference between the temperature inside the room and the one selected in the thermostat.
+-- The default value is 0.3.
+-- @arg data.view A table with a boolean element timeSeries (default true) indicating whether
+-- a time series chart should be drawn.
 -- @image room-temperature.bmp
 RoomTemperature = SysDynModel{ 
 	tempSet     = 20.0,
 	inside      = 15.0, 
 	outside     =  1.0,
-	hour        =    0,
-	climate     = function (hour)
-					return  15 - 0.1*(hour - 12)^2   -- varies btw 1 and 15 degrees
-				end,
+	climate     = function(hour)
+		return  15 - 0.1*(hour - 12)^2   -- varies btw 1 and 15 degrees
+	end,
 	thermalInertia = 0.33, 
 	lossToOutside  = 0.30,
 	finalTime = 24,
-	changes = function (model, time)
-		model.outside = model.climate (time)
+	changes = function(model, time)
+		model.outside = model.climate(time)
 		local inflow  = model.thermalInertia * (model.tempSet - model.inside)
 		local outflow = model.lossToOutside  * (model.inside - model.outside)
-	   model.inside =  model.inside + inflow - outflow
+		model.inside =  model.inside + inflow - outflow
 	end,
 	graphics = { 
 		timeseries = {{"inside", "tempSet", "outside"}}
diff --git a/lua/SysDynModel.lua b/lua/SysDynModel.lua
old mode 100755
new mode 100644
index 480e11e..3331891
--- a/lua/SysDynModel.lua
+++ b/lua/SysDynModel.lua
@@ -36,8 +36,11 @@ end
 -- The default value is one.
 -- x axis.
 -- @arg data.... Any other value that can be used as parameter for the Model.
--- @usage Tube = SysDynModel{
+-- @usage import("sysdyn")
+--
+-- tube = SysDynModel{
 --     water = 20,
+--     finalTime = 20,
 --     changes = function(model)
 --         model.water = model.water - 1
 --     end,
@@ -45,6 +48,8 @@ end
 --         timeseries = {{"water"}},
 --     }
 -- }
+--
+-- tube:execute()
 function SysDynModel(data)
 	verify(data.graphics, "System Dynamics 'graphics' must be provided")
 	verify(data.changes, "System Dynamics 'changes()' must be provided")
@@ -58,7 +63,7 @@ function SysDynModel(data)
 
 	if data.graphics.phasespace then data.view.phaseSpace = true end
 	if data.graphics.timeseries then data.view.timeSeries = true end
-	if data.graphics.cobweb     then data.view.cobweb     = true end
+	if data.graphics.cobweb     then data.view.cobWeb     = true end
 
 	forEachElement(data.graphics, function(idx)
 		if type(idx) ~= "string" then