.. Down} and .. , 71 12 Transformation Cases for the Set of Binary Operations {U p 84 13 Extension of Algorithm 12 with the Idle Operation, Garbage Collection Administrative Logs Procedures at site s, p.104

C. Logs and .. , 179 19 Transforming a Request Against a Log, 179 20 Control Concurrency Algorithm with Garbage Collection Scheme . . . . . . . . . . . . 184

. Otherwise, 1 ) then IT (I(op 1 , op 2 ), I(op j , op 2 )) = I(IT (op 1, op 2 ) and IT (I(op 1 , op 3 ), I(op j , op 3 )) = I(IT (op 1 op 3 ) Since I(IT (op 1

. Accordingly, the similarity is preserved by transformation against normal and idle operations Using the precedent Lemma we show that similarity relation is preserved by transformation against two equal logs. Given a log H and two similar idle operations op 1

. Proof, By induction on H's size and the use of Lemmas 8

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