diff --git a/AlgebraicDataflowArchitectureModel/models/InventoryManagement.model b/AlgebraicDataflowArchitectureModel/models/InventoryManagement.model
index 424e589..31bcdad 100644
--- a/AlgebraicDataflowArchitectureModel/models/InventoryManagement.model
+++ b/AlgebraicDataflowArchitectureModel/models/InventoryManagement.model
@@ -4,7 +4,7 @@
 }
 
 channel ReceivingOrShipping(itemId:Str) {
-	out inventory.{itemId}.count(prev_quantity:Int, receiveOrShip(quantity:Int)) = if((prev_quantity + quantity) >= 0, 
+	out inventory.{itemId}.count(prev_quantity:Int, receiveOrShip(quantity:Int)) = if(prev_quantity + quantity >= 0, 
 																						prev_quantity + quantity, 
 																						prev_quantity)
 }
diff --git a/AlgebraicDataflowArchitectureModel/src/parser/Parser.java b/AlgebraicDataflowArchitectureModel/src/parser/Parser.java
index bc6429b..49d8596 100644
--- a/AlgebraicDataflowArchitectureModel/src/parser/Parser.java
+++ b/AlgebraicDataflowArchitectureModel/src/parser/Parser.java
@@ -405,9 +405,6 @@
 			} else if (operator.equals(OR)) {
 				operators.add(DataTransferModel.or);
 				stream.next();
-			} else if (operator.equals(NEG)) {
-				operators.add(DataTransferModel.neg);
-				stream.next();
 			} else if (operator.equals(DOT)) {
 				// json accessor
 				Expression exp = expressions.remove(0);
@@ -453,15 +450,40 @@
 		ArrayList<Symbol> addSubs = new ArrayList<>();
 		Expression first = expressions.get(0);
 		int i = 1;
+		Term rootTerm = null;
 		for (Symbol op: operators) {
 			Expression second = expressions.get(i);
-			if (op.getName().equals(MUL) || op.getName().equals(DIV) || op.getName().equals(MOD)
-					|| op.getName().equals(EQ) || op.getName().equals(NEQ) || op.getName().equals(GT) || op.getName().equals(LT)
-					|| op.getName().equals(GE) || op.getName().equals(LE) || op.getName().equals(AND) || op.getName().equals(OR)) {
+			if (op.getName().equals(MUL) || op.getName().equals(DIV) || op.getName().equals(MOD)) {
+				// higher priority than add and sub
 				Term term = new Term(op);
 				term.addChild(first);
 				term.addChild(second);
 				first = term;
+			} else if (op.getName().equals(EQ) || op.getName().equals(NEQ) || op.getName().equals(GT) || op.getName().equals(LT)
+						|| op.getName().equals(GE) || op.getName().equals(LE) || op.getName().equals(AND) || op.getName().equals(OR)) {
+				// lower priority than add and sub
+				if (first != null) monomials.add(first);
+				Expression firstMonomial = monomials.get(0);
+				i = 1;
+				for (Symbol op2: addSubs) {
+					Expression secondMonomial = monomials.get(i);
+					Term term = new Term(op2);
+					term.addChild(firstMonomial);
+					term.addChild(secondMonomial);
+					firstMonomial = term;
+					i++;
+				}
+				if (rootTerm == null) {
+					rootTerm = new Term(op);
+					rootTerm.addChild(firstMonomial);
+				} else {
+					rootTerm.addChild(firstMonomial);
+					firstMonomial = rootTerm;
+					rootTerm = new Term(op);
+					rootTerm.addChild(firstMonomial);
+				}
+				monomials.clear();
+				addSubs.clear();
 			} else {
 				// add or sub ==> new monomial
 				monomials.add(first);
@@ -481,7 +503,12 @@
 			firstMonomial = term;
 			i++;
 		}
-		return firstMonomial;
+		if (rootTerm == null) {
+			return firstMonomial;
+		} else {
+			rootTerm.addChild(firstMonomial);
+			return rootTerm;
+		}
 	}
 
 	private Expression parseJsonTerm(TokenStream stream, DataTransferModel model) throws ExpectedRightBracket, WrongJsonExpression, ExpectedColon {
diff --git a/AlgebraicDataflowArchitectureModel/src/simulator/SystemState.java b/AlgebraicDataflowArchitectureModel/src/simulator/SystemState.java
index fc671d8..9a58a33 100644
--- a/AlgebraicDataflowArchitectureModel/src/simulator/SystemState.java
+++ b/AlgebraicDataflowArchitectureModel/src/simulator/SystemState.java
@@ -131,20 +131,33 @@
 			if (resStateValue instanceof Constant) {
 			} else if (resStateValue instanceof Term) {
 				Term jsonValue = (Term) resStateValue;
-				if (jsonValue.getSymbol().equals(DataConstraintModel.addMember)) {
+				Resource res = getResource(resourceIdentifier);
+				ResourceState state = res.getState();
+				ResourceIdentifier createdResource = null;
+				while (jsonValue.getSymbol().equals(DataConstraintModel.addMember)) {
 					Expression childExp = jsonValue.getChild(1);
 					if (childExp instanceof Constant) {
-						Resource res = getResource(resourceIdentifier);
-						ResourceState state = res.getState();
-						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, 
-																							childExp, 
-																							resourceIdentifier.getResourceHierarchy().getChildren().iterator().next());
+						String memberName = ((Constant) childExp).getSymbol().getName().replace("\"", "");
+						ResourceHierarchy childResourceHierarchy = null;
+						for (ResourceHierarchy childRes: resourceIdentifier.getResourceHierarchy().getChildren()) {
+							if (childRes.getResourceName().equals(memberName)) {
+								childResourceHierarchy = childRes;
+								break;
+							}
+						}
+						if (childResourceHierarchy == null) {
+							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), memberName);
+						}
+						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, memberName, childResourceHierarchy);
 						String childId = ((Constant) childExp).toString();
 						Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, jsonValue.getChild(2));
 						((JsonResourceState) state).addChildState(childId, childInfo.getKey());
-						return childInfo.getValue();
+						createdResource = childInfo.getValue();
 					}
+					if (!(jsonValue.getChild(0) instanceof Term)) break;
+					jsonValue = (Term) jsonValue.getChild(0);
 				}
+				return createdResource;
 			}
 		} else {
 			if (resStateValue instanceof Term) {
@@ -217,8 +230,8 @@
 				if (resStateValue instanceof Constant) {
 				} else if (resStateValue instanceof Term) {
 					Term jsonValue = (Term) resStateValue;
-					Map.Entry<ResourceState, ResourceIdentifier> createInfo = null;
 					JsonResourceState state = new JsonResourceState();
+					Map.Entry<ResourceState, ResourceIdentifier> createInfo = null;
 					while (jsonValue.getSymbol().equals(DataConstraintModel.addMember)) {
 						Expression childExp = jsonValue.getChild(1);
 						if (childExp instanceof Constant) {