a

fiber radius dimensionless

b

cell radius dimensionless

b_i,j

bias of i-th neuron in the j-th layer

D

Brownian diffusion coefficient

e

error between the desired and the obtained output

F_i,j(.)

activation function of i-th neuron in the j-th layer

n

particle concentration

n_Df

particle concentration at location D_f

n_Rf

particle concentration at location R_f

n_Uf

particle concentration at location U_f

Pe

Peclet number (= 2aU/D)

R

polar coordinate dimensionless

R²

correlation coefficient

s_i,j-1

output of i-th neuron in the j-1-th layer

s_i,j

output of i-th neuron in the j-1-th layer

U

flow velocity scale

u_r

radial gas velocity

u_

angular gas velocity

v_f

advection velocity

v

activation potential

w_i,k,j-1

weights of i-th neuron in the j-th layer (the second subscript k indicates the neuron in the (j − 1)-th layer from which the connection is being established)

w_i,j,k

weights of i-th neuron in the k-th layer (the second subscript j indicates the neuron in the k-th layer from which the connection is being established)