A Dynamic Analysis of a Motor Vehicle Pollutant Emission Reduction Management Model Based on the SD-GM Approach

Table 11

Description of main variables in stock flow diagram.

Significant variable	Unit	Variable type	Data source
Air pollution charging fee	yuan/day·vehicle	Constant
Air pollution control	Dmnl	Auxiliary variable	M1+M3
Amount of GDP	yuan	Level	M1
Amount of motor vehicles	vehicle	Level	M1
Amount of motor vehicle trips	vehicle	Auxiliary variable
Amount of NOx (PMx) generation	ton	Level	M1
Amount of population	person	Level	M1
Annual dissipation of NOx (PMx)	ton/year	Flow
Annual scrapped	vehicle/year	Flow
Attraction degree of city	%	Constant	M2
Attraction degree of the growth of vehicles	%	Auxiliary variable	M1+M3
Attraction degree of vehicle trips	%	Auxiliary variable	M1+M3
Birth rate	1/year	Constant	M3
Contribution rate of NOx (PMx) from vehicle	%	Constant	M2
Cost of motor vehicle trips	yuan/day·vehicle	Auxiliary variable	M3
Death rate	1/year	Constant	M3
Degree of air pollution	Dmnl	Auxiliary variable	M3
Dissipation and control rate of NOx (PMx)	1/year	Constant	M2
Graphical function of the growth of GDP	Dmnl	Auxiliary variable	M3
Growth of GDP	yuan/year	Flow
Growth rate of motor vehicles	1/year	Auxiliary variable	M1+M3
Growth of motor vehicles	vehicle/year	Flow
Growth of population	person/year	Flow
Growth rate of vehicle ownership	Dmnl	Auxiliary variable	M1+M3
Impact factor of policy	Dmnl	Constant	M3
Net migration	person/year	Flow
Net migration rate	1/year	Constant	M1+M3
NOx (PMx) emissions	ton/year	Flow
Per capita annual income	yuan/person	Auxiliary variable
Per vehicle annual of NOx (PMx) emissions	ton/year·vehicle	Constant	M2
Pollution degree of NOx (PMx)	Dmnl	Auxiliary variable	M1+M3
Population reduction	person/year	Flow
Ratio of motor vehicle trips	%	Constant	M2
Scrap rate	1/year	Constant	M2
The average of net migration rate	1/year	Constant	M1
Weight ratio of PMx (NOx)	%	Auxiliary variable	M3