Modify distance logic

@@ -130,7 +130,7 @@ async def thread(websocket, path):
                     db_embedding = np.frombuffer(row_data['embedding'], dtype=np.float32)
                     db_embedding = db_embedding.reshape((1,512))
                     distance = await get_distance(embedding, db_embedding)
-                    if (distance < 0.4):
+                    if (distance < distance_min):
                         verified_id = row_data['student_id']
                         distance_min = distance
                         break