YES

Problem:
 a(x1) -> x1
 a(b(x1)) -> c(b(a(a(x1))))
 b(x1) -> c(x1)
 c(c(x1)) -> b(x1)

Proof:
 DP Processor:
  DPs:
   a#(b(x1)) -> a#(x1)
   a#(b(x1)) -> a#(a(x1))
   a#(b(x1)) -> b#(a(a(x1)))
   a#(b(x1)) -> c#(b(a(a(x1))))
   b#(x1) -> c#(x1)
   c#(c(x1)) -> b#(x1)
  TRS:
   a(x1) -> x1
   a(b(x1)) -> c(b(a(a(x1))))
   b(x1) -> c(x1)
   c(c(x1)) -> b(x1)
  TDG Processor:
   DPs:
    a#(b(x1)) -> a#(x1)
    a#(b(x1)) -> a#(a(x1))
    a#(b(x1)) -> b#(a(a(x1)))
    a#(b(x1)) -> c#(b(a(a(x1))))
    b#(x1) -> c#(x1)
    c#(c(x1)) -> b#(x1)
   TRS:
    a(x1) -> x1
    a(b(x1)) -> c(b(a(a(x1))))
    b(x1) -> c(x1)
    c(c(x1)) -> b(x1)
   graph:
    c#(c(x1)) -> b#(x1) -> b#(x1) -> c#(x1)
    b#(x1) -> c#(x1) -> c#(c(x1)) -> b#(x1)
    a#(b(x1)) -> c#(b(a(a(x1)))) -> c#(c(x1)) -> b#(x1)
    a#(b(x1)) -> b#(a(a(x1))) -> b#(x1) -> c#(x1)
    a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> c#(b(a(a(x1))))
    a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> b#(a(a(x1)))
    a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(x1))
    a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(x1)
    a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> c#(b(a(a(x1))))
    a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> b#(a(a(x1)))
    a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(a(x1))
    a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(x1)
   CDG Processor:
    DPs:
     a#(b(x1)) -> a#(x1)
     a#(b(x1)) -> a#(a(x1))
     a#(b(x1)) -> b#(a(a(x1)))
     a#(b(x1)) -> c#(b(a(a(x1))))
     b#(x1) -> c#(x1)
     c#(c(x1)) -> b#(x1)
    TRS:
     a(x1) -> x1
     a(b(x1)) -> c(b(a(a(x1))))
     b(x1) -> c(x1)
     c(c(x1)) -> b(x1)
    graph:
     c#(c(x1)) -> b#(x1) -> b#(x1) -> c#(x1)
     a#(b(x1)) -> c#(b(a(a(x1)))) -> c#(c(x1)) -> b#(x1)
     a#(b(x1)) -> b#(a(a(x1))) -> b#(x1) -> c#(x1)
     a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(x1)
     a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(x1))
     a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> b#(a(a(x1)))
     a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> c#(b(a(a(x1))))
     a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(x1)
     a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(a(x1))
     a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> b#(a(a(x1)))
     a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> c#(b(a(a(x1))))
    SCC Processor:
     #sccs: 1
     #rules: 2
     #arcs: 11/36
     DPs:
      a#(b(x1)) -> a#(a(x1))
      a#(b(x1)) -> a#(x1)
     TRS:
      a(x1) -> x1
      a(b(x1)) -> c(b(a(a(x1))))
      b(x1) -> c(x1)
      c(c(x1)) -> b(x1)
     Arctic Interpretation Processor:
      dimension: 2
      interpretation:
       [a#](x0) = [0 0]x0 + [-2],
       
                 [-& 0 ]     [0 ]
       [c](x0) = [1  0 ]x0 + [-&],
       
                 [-& 0 ]     [0]
       [b](x0) = [1  1 ]x0 + [1],
       
                 [0  0 ]     [-2]
       [a](x0) = [-& 0 ]x0 + [-&]
      orientation:
       a#(b(x1)) = [1 1]x1 + [1] >= [0 0]x1 + [-2] = a#(a(x1))
       
       a#(b(x1)) = [1 1]x1 + [1] >= [0 0]x1 + [-2] = a#(x1)
       
               [0  0 ]     [-2]           
       a(x1) = [-& 0 ]x1 + [-&] >= x1 = x1
       
                  [1 1]     [1]    [1 1]     [1]                 
       a(b(x1)) = [1 1]x1 + [1] >= [1 1]x1 + [1] = c(b(a(a(x1))))
       
               [-& 0 ]     [0]    [-& 0 ]     [0 ]        
       b(x1) = [1  1 ]x1 + [1] >= [1  0 ]x1 + [-&] = c(x1)
       
                  [1 0]     [0]    [-& 0 ]     [0]        
       c(c(x1)) = [1 1]x1 + [1] >= [1  1 ]x1 + [1] = b(x1)
      problem:
       DPs:
        
       TRS:
        a(x1) -> x1
        a(b(x1)) -> c(b(a(a(x1))))
        b(x1) -> c(x1)
        c(c(x1)) -> b(x1)
      Qed