diff --git a/vlsisapd/src/dtr/src/PyTechno.cpp b/vlsisapd/src/dtr/src/PyTechno.cpp
index c6fe5d78..e5aeb0b2 100644
--- a/vlsisapd/src/dtr/src/PyTechno.cpp
+++ b/vlsisapd/src/dtr/src/PyTechno.cpp
@@ -1,3 +1,5 @@
+using namespace std;
+
 #include <boost/python.hpp>
 using namespace boost::python;
 
@@ -17,20 +19,21 @@ BOOST_PYTHON_MODULE(pyDTR) {
     ;
 
     // class DTR::Rule
-    class_<Rule>("Rule", init<Name, double, Name, Name, Name>())
+    class_<Rule>("Rule", init<Name, double, Name, Name, Name, Name>())
         // accessors
-        .def("getName"  , &Rule::getName  )
-        .def("getType"  , &Rule::getType  )
-        .def("getValue" , &Rule::getValue )
-        .def("getRef"   , &Rule::getRef   )
-        .def("getLayer1", &Rule::getLayer1)
-        .def("getLayer2", &Rule::getLayer2)
+        .def("getName"         , &Rule::getName         )
+        .def("getType"         , &Rule::getType         )
+        .def("getValue"        , &Rule::getValue        )
+        .def("getValueAsString", &Rule::getValueAsString)
+        .def("getRef"          , &Rule::getRef          )
+        .def("getLayer1"       , &Rule::getLayer1       )
+        .def("getLayer2"       , &Rule::getLayer2       )
         // modifiers
-        .def("setType"  , &Rule::setType  )
+        .def("setType"         , &Rule::setType         )
     ; 
 
     // class DTR::ARule derived from DTR::Rule
-    class_<ARule, bases<Rule> >("ARule", init<Name, double, Name, Name, Name>())
+    class_<ARule, bases<Rule> >("ARule", init<Name, double, Name, Name, Name, Name>())
     ;
 
     // class DTR::Techno
@@ -38,11 +41,14 @@ BOOST_PYTHON_MODULE(pyDTR) {
         .def("readFromFile", &Techno::readFromFile, return_value_policy<manage_new_object>())
         .staticmethod("readFromFile")
 
-        .def("getName"     , &Techno::getName )
-        .def("getUnit"     , &Techno::getUnit )
-        .def("getValue"    , static_cast<double(Techno::*)(Name            )>(&Techno::getValue))
-        .def("getValue"    , static_cast<double(Techno::*)(Name, Name      )>(&Techno::getValue))
-        .def("getValue"    , static_cast<double(Techno::*)(Name, Name, Name)>(&Techno::getValue))
+        .def("getName"         , &Techno::getName )
+        .def("getUnit"         , &Techno::getUnit )
+        .def("getValue"        , static_cast<double(Techno::*)(Name            )>(&Techno::getValue))
+        .def("getValue"        , static_cast<double(Techno::*)(Name, Name      )>(&Techno::getValue))
+        .def("getValue"        , static_cast<double(Techno::*)(Name, Name, Name)>(&Techno::getValue))
+        .def("getValueAsString", static_cast<string(Techno::*)(Name            )>(&Techno::getValueAsString))
+        .def("getValueAsString", static_cast<string(Techno::*)(Name, Name      )>(&Techno::getValueAsString))
+        .def("getValueAsString", static_cast<string(Techno::*)(Name, Name, Name)>(&Techno::getValueAsString))
     ;
 
     // DTRException translator
diff --git a/vlsisapd/src/dtr/src/Techno.cpp b/vlsisapd/src/dtr/src/Techno.cpp
index 5f80d5e7..346de4e1 100644
--- a/vlsisapd/src/dtr/src/Techno.cpp
+++ b/vlsisapd/src/dtr/src/Techno.cpp
@@ -34,14 +34,14 @@ namespace {
 namespace DTR {
 Techno::Techno(Name name, Name unit) : _name(name), _unit(unit) {}
 
-Rule* Techno::addRule (Name name, double value, Name ref, Name layer1, Name layer2) {
-    Rule* rule = new Rule(name, value, ref, layer1, layer2);
+Rule* Techno::addRule (Name name, double value, Name valueStr, Name ref, Name layer1, Name layer2) {
+    Rule* rule = new Rule(name, value, valueStr, ref, layer1, layer2);
     _rules.push_back(rule);
     return rule;
 }
 
-ARule* Techno::addARule (Name name, double value, Name ref, Name layer1, Name layer2) {
-    ARule* arule = new ARule(name, value, ref, layer1, layer2);
+ARule* Techno::addARule (Name name, double value, Name valueStr, Name ref, Name layer1, Name layer2) {
+    ARule* arule = new ARule(name, value, valueStr, ref, layer1, layer2);
     _rules.push_back(arule);
     return arule;
 }
@@ -86,6 +86,46 @@ double Techno::getValue(Name name, Name layer1, Name layer2) {
     throw DTRException(error);
 }
 
+string Techno::getValueAsString(Name name) {
+    return getValueAsString(name, Name(""), Name(""));
+}
+
+string Techno::getValueAsString(Name name, Name layer) {
+    return getValueAsString(name, layer, Name(""));
+}
+
+string Techno::getValueAsString(Name name, Name layer1, Name layer2) {
+    bool testL1   = (layer1 == Name("")) ? false : true;
+    bool testL2   = (layer2 == Name("")) ? false : true;
+
+    for (size_t i = 0 ; i < _rules.size() ; i++) {
+        Rule* rule = _rules[i];
+        if (rule->getName() == name) {
+            if (testL1) {
+                if (rule->getLayer1() == layer1) {
+                    if (testL2) {
+                        if (rule->getLayer2() == layer2) {
+                            return rule->getValueAsString();
+                        }
+                    } else {
+                        return rule->getValueAsString();
+                    }
+                }
+            } else {
+                return rule->getValueAsString();
+            }
+        }
+    }
+    string error ("[ERROR] Could not found rule: ");
+    error += name.getString();
+    error += ".";
+    error += layer1.getString();
+    error += ".";
+    error += layer2.getString();
+    error += ".";
+    throw DTRException(error);
+}
+
 Techno* Techno::readFromFile(const string filePath) {
     LIBXML_TEST_VERSION;
     Techno* techno = NULL;
@@ -136,18 +176,21 @@ Techno* Techno::readFromFile(const string filePath) {
                                 Name layer1 ((const char*)layer1C);
                                 Name layer2 ((const char*)layer2C);
                                 double value = ::getValue<double>(valueC);
-                                rule = techno->addRule(name, value, ref, layer1, layer2);
+                                Name valueStr ((const char*)valueC);
+                                rule = techno->addRule(name, value, valueStr, ref, layer1, layer2);
                             } else if (nameC && layerC && valueC && refC) {// rule with only one layer
                                 Name name  ((const char*)nameC);
                                 Name ref   ((const char*)refC);
                                 Name layer ((const char*)layerC);
                                 double value = ::getValue<double>(valueC);
-                                rule = techno->addRule(name, value, ref, layer);
+                                Name valueStr ((const char*)valueC);
+                                rule = techno->addRule(name, value, valueStr, ref, layer);
                             } else if (nameC && valueC && refC) { // rule without layer
                                 Name name ((const char*)nameC);
                                 Name ref  ((const char*)refC);
                                 double value = ::getValue<double>(valueC);
-                                rule = techno->addRule(name, value, ref);
+                                Name valueStr ((const char*)valueC);
+                                rule = techno->addRule(name, value, valueStr, ref);
                             } else { // invalid case
                                 throw DTRException("[ERROR] properties of 'rule' node must be ('name', 'value', 'ref') or ('name', 'layer', 'value', 'ref') or ('name', 'layer1', 'layer2', 'value', 'ref').");
                                 return NULL;
@@ -168,7 +211,8 @@ Techno* Techno::readFromFile(const string filePath) {
                                 Name layer2 ((const char*)layer2C);
                                 Name ref    ((const char*)refC);
                                 double value = ::getValue<double>(valueC);
-                                techno->addARule(name, value, ref, layer1, layer2);
+                                Name valueStr ((const char*)valueC);
+                                techno->addARule(name, value, valueStr, ref, layer1, layer2);
                             } else {
                                 throw DTRException("[ERROR] 'arule' node must have 'name', 'layer1', 'layer2', 'value' and 'ref' properties.");
                                 return NULL;
diff --git a/vlsisapd/src/dtr/src/vlsisapd/dtr/Rules.h b/vlsisapd/src/dtr/src/vlsisapd/dtr/Rules.h
index 6e365cb8..cf1dedfc 100644
--- a/vlsisapd/src/dtr/src/vlsisapd/dtr/Rules.h
+++ b/vlsisapd/src/dtr/src/vlsisapd/dtr/Rules.h
@@ -10,16 +10,19 @@
 #ifndef __DTR_RULES_H__
 #define __DTR_RULES_H__
 
+#include "vlsisapd/dtr/Name.h"
+
 namespace DTR {
 class Rule {
     public:
-    Rule(Name name, double value, Name ref, Name layer1, Name layer2)
-        : _name(name), _type(Name("")), _value(value), _ref(ref), _layer1(layer1), _layer2(layer2) {};
+    Rule(Name name, double value, Name valueStr, Name ref, Name layer1, Name layer2)
+        : _name(name), _type(Name("")), _value(value), _valueStr(valueStr), _ref(ref), _layer1(layer1), _layer2(layer2) {};
     
     // accessors
     inline Name   getName();
     inline Name   getType();
     inline double getValue();
+    inline std::string getValueAsString();
     inline Name   getRef();
     inline Name   getLayer1();
     virtual inline Name   getLayer2(); // add virtual so the Rule object is polymorphic
@@ -32,6 +35,7 @@ class Rule {
     Name   _name;
     Name   _type;
     double _value;
+    Name   _valueStr;
     Name   _ref;
     Name   _layer1;
     Name   _layer2;
@@ -39,8 +43,8 @@ class Rule {
 
 class ARule : public Rule {
     public:
-    ARule(Name name, double value, Name ref, Name layer1, Name layer2)
-        : Rule(name, value, ref, layer1, layer2) {};
+    ARule(Name name, double value, Name valueStr, Name ref, Name layer1, Name layer2)
+        : Rule(name, value, valueStr, ref, layer1, layer2) {};
 };
     
 inline Name   Rule::getName()   { return _name;   };
@@ -49,6 +53,7 @@ inline double Rule::getValue()  { return _value;  };
 inline Name   Rule::getRef()    { return _ref;    };
 inline Name   Rule::getLayer1() { return _layer1; };
 inline Name   Rule::getLayer2() { return _layer2; };
+inline std::string Rule::getValueAsString() { return _valueStr.getString(); };
 
 inline void   Rule::setType(Name type) { _type = type; };
 } // namespace DTR
diff --git a/vlsisapd/src/dtr/src/vlsisapd/dtr/Techno.h b/vlsisapd/src/dtr/src/vlsisapd/dtr/Techno.h
index 8c676807..9808cd6a 100644
--- a/vlsisapd/src/dtr/src/vlsisapd/dtr/Techno.h
+++ b/vlsisapd/src/dtr/src/vlsisapd/dtr/Techno.h
@@ -28,13 +28,17 @@ class Techno {
     inline Name getUnit();
     inline std::vector<Rule*>&  getRules();
 
-    Rule*  addRule (Name name, double value, Name ref, Name layer1=Name(""), Name layer2=Name(""));
-    ARule* addARule(Name name, double value, Name ref, Name layer1         , Name layer2);
+    Rule*  addRule (Name name, double value, Name valueStr, Name ref, Name layer1=Name(""), Name layer2=Name(""));
+    ARule* addARule(Name name, double value, Name valueStr, Name ref, Name layer1         , Name layer2);
 
     double getValue(Name name);
     double getValue(Name name, Name layer);
     double getValue(Name name, Name layer1, Name layer2);
     
+    std::string getValueAsString(Name name);
+    std::string getValueAsString(Name name, Name layer);
+    std::string getValueAsString(Name name, Name layer1, Name layer2);
+    
     bool writeToFile(std::string filePath);
     static Techno* readFromFile(const std::string filePath);