YES

Problem 1: 

(VAR v_NonEmpty:S x1:S)
(RULES
a(b(x1:S)) -> b(a(x1:S))
a(c(x1:S)) -> c(a(x1:S))
a(x1:S) -> b(c(x1:S))
d(c(x1:S)) -> d(a(x1:S))
)

Problem 1: 

Dependency Pairs Processor:
-> Pairs:
 A(b(x1:S)) -> A(x1:S)
 A(c(x1:S)) -> A(x1:S)
 D(c(x1:S)) -> A(x1:S)
 D(c(x1:S)) -> D(a(x1:S))
-> Rules:
 a(b(x1:S)) -> b(a(x1:S))
 a(c(x1:S)) -> c(a(x1:S))
 a(x1:S) -> b(c(x1:S))
 d(c(x1:S)) -> d(a(x1:S))

Problem 1: 

SCC Processor:
-> Pairs:
 A(b(x1:S)) -> A(x1:S)
 A(c(x1:S)) -> A(x1:S)
 D(c(x1:S)) -> A(x1:S)
 D(c(x1:S)) -> D(a(x1:S))
-> Rules:
 a(b(x1:S)) -> b(a(x1:S))
 a(c(x1:S)) -> c(a(x1:S))
 a(x1:S) -> b(c(x1:S))
 d(c(x1:S)) -> d(a(x1:S))
->Strongly Connected Components:
->->Cycle:
->->-> Pairs:
 A(b(x1:S)) -> A(x1:S)
 A(c(x1:S)) -> A(x1:S)
->->-> Rules:
 a(b(x1:S)) -> b(a(x1:S))
 a(c(x1:S)) -> c(a(x1:S))
 a(x1:S) -> b(c(x1:S))
 d(c(x1:S)) -> d(a(x1:S))
->->Cycle:
->->-> Pairs:
 D(c(x1:S)) -> D(a(x1:S))
->->-> Rules:
 a(b(x1:S)) -> b(a(x1:S))
 a(c(x1:S)) -> c(a(x1:S))
 a(x1:S) -> b(c(x1:S))
 d(c(x1:S)) -> d(a(x1:S))


The problem is decomposed in 2 subproblems.

Problem 1.1: 

Subterm Processor:
-> Pairs:
 A(b(x1:S)) -> A(x1:S)
 A(c(x1:S)) -> A(x1:S)
-> Rules:
 a(b(x1:S)) -> b(a(x1:S))
 a(c(x1:S)) -> c(a(x1:S))
 a(x1:S) -> b(c(x1:S))
 d(c(x1:S)) -> d(a(x1:S))
->Projection:
 pi(A) = 1

Problem 1.1: 

SCC Processor:
-> Pairs:
 Empty
-> Rules:
 a(b(x1:S)) -> b(a(x1:S))
 a(c(x1:S)) -> c(a(x1:S))
 a(x1:S) -> b(c(x1:S))
 d(c(x1:S)) -> d(a(x1:S))
->Strongly Connected Components:
 There is no strongly connected component

The problem is finite.

Problem 1.2: 

Reduction Pair Processor:
-> Pairs:
 D(c(x1:S)) -> D(a(x1:S))
-> Rules:
 a(b(x1:S)) -> b(a(x1:S))
 a(c(x1:S)) -> c(a(x1:S))
 a(x1:S) -> b(c(x1:S))
 d(c(x1:S)) -> d(a(x1:S))
-> Usable rules:
 a(b(x1:S)) -> b(a(x1:S))
 a(c(x1:S)) -> c(a(x1:S))
 a(x1:S) -> b(c(x1:S))
->Interpretation type:
 Linear
->Coefficients:
 Natural Numbers
->Dimension:
 1
->Bound:
 2
->Interpretation:
 
[a](X) = X
[b](X) = 0
[c](X) = 2.X + 2
[D](X) = 2.X

Problem 1.2: 

SCC Processor:
-> Pairs:
 Empty
-> Rules:
 a(b(x1:S)) -> b(a(x1:S))
 a(c(x1:S)) -> c(a(x1:S))
 a(x1:S) -> b(c(x1:S))
 d(c(x1:S)) -> d(a(x1:S))
->Strongly Connected Components:
 There is no strongly connected component

The problem is finite.