diff --git a/AlgebraicDataflowArchitectureModel/models/StockManagement.model b/AlgebraicDataflowArchitectureModel/models/StockManagement.model
index d3ed3f2..131b7ef 100644
--- a/AlgebraicDataflowArchitectureModel/models/StockManagement.model
+++ b/AlgebraicDataflowArchitectureModel/models/StockManagement.model
@@ -2,46 +2,45 @@
 	stock := nil
 	shortage := nil
 }
+
+channel CIO_enter {
+	out arrival(s:Tuple, arrive(item:Str, num:Int)) == tuple(item, num)
+}
+
 channel CIO_req {
 	out request(r:Tuple, req(item:Str, num:Int)) == tuple(item, num)
 }
 
-channel CIO_enter {
-	out entering(e:Tuple, enter(item:Str, num:Int)) == tuple(item, num)
-}
-
 channel C1 {
-	in request(r, update1(r2)) == r2
-	out stock(st:Map, update1(r2)) == if(le(snd(r2), lookup(st, fst(r2))), 
-											insert(st, fst(r2), lookup(st, fst(r2)) - snd(r2)), 
-											st)
-	out shortage(sh:Map, update1(r2)) == if(le(snd(r2), lookup(sh, fst(r2))), 
-											sh, 
-											insert(sh, fst(r2), lookup(sh, fst(r2)) + snd(r2)))
+	in arrival(ar, update1(ar2, st)) == ar2
+	ref stock(st:Map, update1(ar2, st))
+	out available(av:Tuple, update1(ar2, st)) == tuple(fst(ar2), snd(ar2) + lookup(st, fst(ar2)))
 }
 
 channel C2 {
-	in entering(e, update2(e2, st)) == e2
-	ref stock(st, update2(e2, st))
-	out shortage(sh, update2(e2, st)) == if(ge(snd(e2) + lookup(st, fst(e2)), lookup(sh, fst(e2))), 
-											insert(sh, fst(e2), 0), 
-											sh)
+	in available(av, update2(av2, sh)) == av2
+	ref shortage(sh, update2(av2, sh))
+	out deriver(dr:Tuple, update2(av2, sh)) == if(ge(snd(av2), lookup(sh, fst(av2))), 
+												tuple(fst(av2), lookup(sh, fst(av2)), snd(av2) - lookup(sh, fst(av2))), 
+												tuple(fst(av2), 0, snd(av2)))
+	out shortage(s, update2(av2, sh)) == if(ge(snd(av2), lookup(s, fst(av2))), 
+												insert(s, fst(av2), 0), 
+												s)
 }
 
 channel C3 {
-	in entering(e, update3(e2, sh)) == e2
-	ref shortage(sh, update3(e2, sh))
-	out stock(st, update3(e2, sh)) == if(ge(snd(e2) + lookup(st, fst(e2)), lookup(sh, fst(e2))), 
-											insert(st, fst(e2), snd(e2) + lookup(st, fst(e2)) - lookup(sh, fst(e2))), 
-											insert(st, fst(e2), snd(e2) + lookup(st, fst(e2))))
+	in deriver(dr, update3(dr2)) == dr2
+	out stock(st, update3(dr2)) == insert(st, fst(dr2), snd(snd(dr2)))
+	out shipping(sp:Tuple, update3(dr2)) == tuple(fst(dr2), fst(snd(dr2)))
 }
 
 channel C4 {
-	in entering(e, update4(e2, sh, st)) == e2
-	ref shortage(sh, update4(e2, sh, st))
-	ref stock(st, update4(e2, sh, st))
-	out dispatching(d:Tuple, update4(e2, sh, st)) == if(and(gt(lookup(sh, fst(e2)), 0), ge(snd(e2) + lookup(st, fst(e2)), lookup(sh, fst(e2)))), 
-														tuple(fst(e2), lookup(sh, fst(e2))), 
-														null)
-}
-
+	in request(rq, update4(rq2, st)) == rq2
+	ref stock(st, update4(rq2, st))
+	out deriver(dr, update4(rq2, st)) == if(ge(lookup(st, fst(rq2)), snd(rq2)), 
+												tuple(fst(rq2), snd(rq2), lookup(st, fst(rq2)) - snd(rq2)), 
+												tuple(fst(rq2), 0, lookup(st, fst(rq2))))
+	out shortage(sh, update4(rq2, st)) == if(ge(lookup(st, fst(rq2)), snd(rq2)), 
+												sh, 
+												insert(sh, fst(rq2), lookup(sh, fst(rq2)) + snd(rq2)))
+}
\ No newline at end of file