. 2023 Jan 25;120:105903. doi: 10.1016/j.engappai.2023.105903

Table 2.

Notation for the proposed RSC model.

Indices

$i \in I$	PPE waste producer
$j \in J$	Selected location in the environment
$k \in K$	Collection center
$l \in L$	Separation center
$m \in M$	Treatment center
$n \in N$	Recycling center
$o \in O$	Burial center
$q \in Q$	Market
$p \in P$	Waste type
$t \in T$	Period

Parameters

- Transportation Cost (TC)

$T C I_{i l}$	TC between waste producer (i) and separation center (l)
$T C J_{j k}$	TC between location (j) and collection center (k)
$T C K_{k l}$	TC between collection center (k) and separation center (l)
$T C L_{l m}$	TC between PPE separation center (l) and treatment center (m)
$T C T_{l n}$	TC between PPE separation center (l) and recycling center (n)
$T C M_{m o}$	TC between PPE treatment center (m) and burial center (o)
$T C N_{n q}$	TC between PPE recycling center (n) and market (q)

- Operation Cost (OC)

$O C K_{k}$	Collection cost for collection center (k) if opens
$O C L_{l}$	Separation cost for treatment center (l) if opens
$O C M_{m}$	Treatment cost for treatment center (m) if opens
$O C N_{n}$	Recycle cost for recycling center (n) if opens
$O C O_{o}$	Burial cost for burial center (o) if opens

- Fixed Cost (FC)

$F C K_{k}$	FC for collection center (k) if opens
$F C L_{l}$	FC for separation center (l) if opens
$F C M_{m}$	FC for treatment center (m) if opens
$F C N_{n}$	FC for recycling center (n) if opens
$F C O_{o}$	FC for burial center (o) if opens

- Transportation Risk Possibility (RP) for waste type (p)

$R P I_{i l p}$	RP between waste producer (i) and separation center (l)
$R P J_{j k p}$	RP between location (j) and collection center (k)
$R P K_{k l p}$	RP between collection center (k) and separation center (l)
$R P L_{l m p}$	RP between separation center (l) and treatment center (m)
$R P T_{l n p}$	RP between separation center (l) and recycling center (n)
$R P M_{m o p}$	RP between treatment center (m) and burial center (o)
$R P N_{n q p}$	RP between recycling center (n) and market (q)

- The number of created Job Opportunities (JO) in period (t)

$J O C_{k t}$	By collection center (k)
$J O S_{l t}$	By separation center (l)
$J O T_{m t}$	By treatment center (m)
$J O R_{n t}$	By recycling center (n)
$J O B_{o t}$	By burial center (o)

- Environmental Impact per unit (EI) for waste type (p) in period (t)

$E I I_{i l p t}$	Transportation between waste producer (i) and separation center (l)
$E I J_{j k p t}$	Transportation between location (j) and collection center (k)
$E I K_{k l p t}$	Transportation between collection center (k) and separation center (l)
$E I L_{l m p t}$	Transportation between separation center (l) and treatment center (m)
$E I G_{l n p t}$	Transportation between separation center (l) and recycling center (n)
$E I M_{m o p t}$	Transportation between treatment center (m) and burial center (o)
$E I N_{n q p t}$	Transportation between recycling center (n) and market (q) per unit
$E I C_{k t}$	Establishment of collection center (k)
$E I S_{l t}$	Establishment of separation center (l)
$E I T_{m t}$	Establishment of treatment center (m)
$E I R_{n t}$	Establishment of recycling center (n)
$E I B_{o t}$	Establishment of burial center (o)

- CO₂Emission per unit (CE) in period (t) for waste type (p)

$C E I_{i l p t}$	Transportation between waste producer (i) and separation center (l)
$C E J_{j k p t}$	Transportation between location (j) and collection center (k)
$C E K_{k l p t}$	Transportation between collection center (k) and separation center (l)
$C E L_{l m p t}$	Transportation between separation center (l) and treatment center (m)
$C E T_{l n p t}$	Transportation between separation center (l) and recycling center (n)
$C E M_{m o p t}$	Transportation between treatment center (m) and burial center (o)
$C E N_{n q p t}$	Transportation between recycling center (n) and market (q)

- Rate (R)

$α^{c c}$	The processing rate of collection centers
$α^{s p}$	The processing rate of separation centers
$α^{t r}$	The processing rate of treatment centers
$α^{r c}$	The processing rate of recycling centers
$α_{t}$	Recyclable amount of waste in period (t)
$1 - α_{t}$	Non-recyclable amount of waste in period (t)

Variables

- Transported Amount (TA) in period (t) for waste type (p)

$T A I_{i l p t}$	TA between waste producer (i) and separation center (l)
$T A J_{j k p t}$	TA between environment (j) and collection center (k)
$T A K_{k l p t}$	TA between collection center (k) and separation center (l)
$T A L_{l m p t}$	TA between separation center (l) and treatment center (m)
$T A T_{l n p t}$	TA between separation center (l) and recycling center (n)
$T A M_{m o p t}$	TA between treatment center (m) and burial center (o)
$T A N_{n q p t}$	TA between recycling center (n) and market (q)

- Processed Amount (PA) in period (t)

$P A C_{k t}$	The collected amount by collection center (k)
$P A S_{l t}$	The separated amount by separation center (l)
$P A T_{m t}$	The treated amount by treatment center (m)
$P A R_{n t}$	The recycled amount by recycling center (n)

- Implementation (IP) in period (t)

$I P C_{k t}$	If collection center (k) is implemented equals 1; otherwise, 0.
$I P S_{l t}$	If separation center (l) is implemented equals 1; otherwise, 0.
$I P T_{m t}$	If treatment center (m) is implemented equals 1; otherwise, 0.
$I P R_{n t}$	If recycling center (n) is implemented equals 1; otherwise, 0.
$I P B_{o t}$	If burial center (o) is implemented equals 1; otherwise, 0.