diff --git a/AlgebraicDataflowArchitectureModel/models/GroupChat.model b/AlgebraicDataflowArchitectureModel/models/GroupChat.model
index 634ddf0..1203e1a 100644
--- a/AlgebraicDataflowArchitectureModel/models/GroupChat.model
+++ b/AlgebraicDataflowArchitectureModel/models/GroupChat.model
@@ -22,6 +22,6 @@
 	in groups.{gid}.messages(prevMesList, notify(m)) = mesList
 	for EachMember(mno:Int) {
 		ref groups.{gid}.members.{mno}(m.{mno}:Str, notify(m))
-		out accounts.{m.{mno}}.notifications(prevNtMap:Map, notify(m)) = insert(prevNtMap, gid, true)
+		out accounts.{m.{mno}:Str}.notifications(prevNtMap:Map, notify(m)) = insert(prevNtMap, gid, true)
 	}
 }
diff --git a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/ResourcePath.java b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/ResourcePath.java
index 293d148..c1125f1 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/ResourcePath.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/ResourcePath.java
@@ -175,6 +175,15 @@
 		return curPath;
 	}
 	
+	public boolean isAncestorOf(ResourcePath another) {
+		Set<ResourcePath> ancestors = new HashSet<>();
+		while (another != null) {
+			ancestors.add(another);
+			another = another.getParent();
+		}
+		return ancestors.contains(this);
+	}
+	
 	public String toString() {
 		return resourceHierarchy.toString(pathParams);
 	}
diff --git a/AlgebraicDataflowArchitectureModel/src/models/dataFlowModel/ResourceNode.java b/AlgebraicDataflowArchitectureModel/src/models/dataFlowModel/ResourceNode.java
index d382534..8dea216 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/dataFlowModel/ResourceNode.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/dataFlowModel/ResourceNode.java
@@ -136,6 +136,10 @@
 		return inSide.get(channel);
 	}
 	
+	public Set<DataTransferChannel> getInSideChannels() {
+		return inSide.keySet();
+	}
+	
 	public Collection<ResourcePath> getOutSideResources() {
 		return outSide.values();
 	}
@@ -144,7 +148,7 @@
 		return outSide.get(channel);
 	}
 	
-	public Set<DataTransferChannel> getOutSideChannel() {
+	public Set<DataTransferChannel> getOutSideChannels() {
 		return outSide.keySet();
 	}