diff --git a/CanonicalDescription/test4/README.md b/CanonicalDescription/test4/README.md
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+Tests 3 : 2 reactors, 1 deployed at the start 1 at midpoint over 120 years
+===========================================================================
+120 year simulation, two reactors, fixed fuel recipe, first reactor operates for 120 years, second reactor starts at midpoint
+Definition
+----------------
+120 year simulation, 2 reactors, fixed fuel recipe, 120 years operation
+
+Reactor : 
+* Type: LWR, 
+* **Fuel**: UOX 3.25%w enriched uranium, 
+* **Mass**: 82 tons (Oxyde Metal),
+* **Thermal Power**: 2875e6 W -- **Efficiency**: 34%,  
+* **Discharge burn-up** : 43.03 GWd/tonne -- Full Cycle length 3y, 
+* **Capacity factor**: 1, 
+* **Suggested recipes**:
+  * **Fresh UOX** :
+    * <sup>235</sup>U   :    3.25%w
+    * <sup>238</sup>U   :   96.75%w
+    * <sup>16</sup>O    :   13.44%w \
+    * the %w are normalize to the quantity of uranium... but because the reactor fuel mass is given in oxyde metal, one provides also the corresponding oxygen quantity
+
+  * **Used UOX** @43.03 GWd/tonne (atomic):
+    * <sup>234</sup>U   :   0.00026%
+    * <sup>235</sup>U   :   0.52485%
+    * <sup>236</sup>U   :   0.41405%
+    * <sup>238</sup>U   :  89.33000%
+    * <sup>238</sup>Pu  :   0.02294%
+    * <sup>239</sup>Pu  :   0.54288%
+    * <sup>240</sup>Pu  :   0.24718%
+    * <sup>241</sup>Pu  :   0.15922%
+    * <sup>242</sup>Pu  :   0.08248%
+    * <sup>241</sup>Am  :   0.00399%
+    * <sup>242</sup>Am* :   0.00008%
+    * <sup>243</sup>Am  :   0.01890%
+    * <sup>242</sup>Cm  :   0.00208%
+    * <sup>243</sup>Cm  :   0.00005%
+    * <sup>244</sup>Cm  :   0.00771%
+    * <sup>245</sup>Cm  :   0.00049%
+    * <sup>237</sup>Np  :   0.05255%
+    * <sup>16</sup>O    : 191.34628%
+
+Output
+----------
+TBD
diff --git a/CanonicalDescription/test4/pb4.json b/CanonicalDescription/test4/pb4.json
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+{
+  "materials": {
+    "pwr_uox": {"attributes": {"recipe": true},
+      "constraints": [
+                      ["U235", 3.25],
+                      ["U238", 96.75],
+                      ["O16", 13.44]],
+      "metadata": {}
+    },
+    "spent_pwr_uox":
+    {"attributes": {"recipe": false},
+      "constraints": [],
+      "metadata": {
+        "suggested_composition": [
+                                 ["U234", 0.00026],
+                                 ["U235", 0.52485],
+                                 ["U236", 0.41405],
+                                 ["U238", 89.33000],
+                                 ["PU238", 0.02294],
+                                 ["PU239", 0.54288],
+                                 ["PU240", 0.24718],
+                                 ["PU241", 0.15922],
+                                 ["PU242", 0.08248],
+                                 ["AM241", 0.00339],
+                                 ["AM242m", 0.00008],
+                                 ["AM243", 0.01890],
+                                 ["CM242", 0.00208],
+                                 ["CM243", 0.00005],
+                                 ["CM244", 0.00771],
+                                 ["CM245", 0.00049],
+                                 ["NP237", 0.05255],
+                                 ["O16", 191.34628]]
+      }
+    }
+  },
+
+  "facilities": {
+    "lwr_reactor_1": {
+      "metadata": {"type": "reactor"},
+      "attributes": {
+        "thermal_power": ["float", "GWt"],
+        "efficiency": ["float", "percent"],
+        "cycle_length": ["int", "EFPD"],
+        "capacity_factor": ["float", "percent"],
+        "lifetime":  ["int", "year"],
+        "fuels":  ["nea_pwr_uox"],
+        "batches": ["int", "", ["pwr_uox"]],
+        "core_loading": ["float", "tHM", ["pwr_uox"]],
+        "burnup": ["float", "GWd/tHM", ["pwr_uox"]],
+        "storage_time": ["int", "year", ["pwr_uox"]],
+        "cooling_time": ["int", "year", ["pwr_uox"]]
+      },
+      "constraints": [
+                      ["thermalPower", 2.8387],
+                      ["efficiency", 34.0],
+                      ["cycle_length", 365.25],
+                      ["capacity_factor", 100],
+                      ["lifetime", 120],
+                      ["batches", 3, "pwr_uox"],
+                      ["core_loading", 82, "pwr_uox"],
+                      ["burnup", 43.03, "pwr_uox"],
+                      ["storage_time", 0, "pwr_uox"],
+                      ["cooling_time", 0, "pwr_uox"]],
+      "inputs": ["pwr_uox"],
+      "outputs": ["spent_pwr_uox"]
+    },
+
+    "lwr_reactor": {
+      "metadata": {"type": "reactor"},
+      "attributes": {
+        "thermal_power": ["float", "GWt"],
+        "efficiency": ["float", "percent"],
+        "cycle_length": ["int", "EFPD"],
+        "capacity_factor": ["float", "percent"],
+        "lifetime":  ["int", "year"],
+        "fuels":  ["nea_pwr_uox"],
+        "batches": ["int", "", ["pwr_uox"]],
+        "core_Loading": ["float", "tHM", ["pwr_uox"]],
+        "burnup": ["float", "GWd/tHM", ["pwr_uox"]],
+        "storage_time": ["int", "year", ["pwr_uox"]],
+        "cooling_time": ["int", "year", ["pwr_uox"]]
+      },
+      "constraints": [
+                      ["thermal_power", 2.8387],
+                      ["efficiency", 34.0],
+                      ["cycle+length", 365.25],
+                      ["capacity_factor", 100],
+                      ["lifetime", 120],
+                      ["batches", 3, "pwr_uox"],
+                      ["core_Loading", 82, "pwr_uox"],
+                      ["burnup", 43.03, "pwr_uox"],
+                      ["storage_time", 0, "pwr_uox"],
+                      ["cooling_time", 0, "pwr_uox"]],
+      "inputs": ["pwr_uox"],
+      "outputs": ["spent_pwr_uox"]
+    },
+
+    "repository": {
+      "metadata": {
+        "type":"repository"
+      },
+      "attributes": {},
+      "constraints": [],
+      "inputs": ["spent_pwr_uox"]
+    }
+  },
+
+  "fuel_cycle": {
+    "attributes": {
+      "grid": "year",
+      "initial_conditions": {
+        "lwr_reactor_power": ["GWe", ["lwr_reactor"]],
+        "repository": 1
+      },
+      "demands": {}
+    },
+
+    "constraints": {
+      "grid": [0, 120],
+      "demands": {"lwr_reactor_power": {
+        "grid": [0, 120],
+        "growth": {
+          "type": "linear",
+          "period1": {
+            "start_time": 0,
+            "start_value": 1,
+            "slope": 0.017,
+          }
+        }
+      }
+      }
+    }
+    
+  }
+}