diff --git a/config/default.py b/config/default.py
index aebb516..facf942 100644
--- a/config/default.py
+++ b/config/default.py
@@ -8,27 +8,25 @@ CELERY_RESULT_BACKEND = 'redis://localhost:6379/0'
 
 from datetime import timedelta
 
-beat_schedule = {
+CELERYBEAT_SCHEDULE = {
     'update-ddb': {
-        'task': 'ogn_python.collect.celery.import_ddb',
-        'schedule': timedelta(minutes=15),
+        'task': 'import_ddb',
+        'schedule': timedelta(minutes=1),
     },
     'update-country-codes': {
-        'task': 'ogn_python.collect.celery.update_receivers_country_code',
-        'schedule': timedelta(minutes=5),
+        'task': 'update_receivers_country_code',
+        'schedule': timedelta(minutes=1),
     },
     'update-takeoff-and-landing': {
-        'task': 'ogn_python.collect.celery.update_takeoff_landings',
-        'schedule': timedelta(minutes=15),
+        'task': 'update_takeoff_landings',
+        'schedule': timedelta(minutes=1),
     },
     'update-logbook': {
-        'task': 'ogn_python.collect.celery.update_logbook_entries',
-        'schedule': timedelta(minutes=15),
+        'task': 'update_logbook_entries',
+        'schedule': timedelta(minutes=1),
     },
     'update-max-altitudes': {
-        'task': 'ogn_python.collect.celery.update_logbook_max_altitude',
-        'schedule': timedelta(minutes=15),
+        'task': 'update_logbook_max_altitude',
+        'schedule': timedelta(minutes=1),
     },
 }
-
-timezone = 'UTC'
diff --git a/ogn_python/collect/celery.py b/ogn_python/collect/celery.py
index 845d927..3e3ded8 100644
--- a/ogn_python/collect/celery.py
+++ b/ogn_python/collect/celery.py
@@ -2,12 +2,12 @@ import datetime
 
 from celery.utils.log import get_task_logger
 
-from ogn_python.collect.takeoff_landings import update_takeoff_landings
+from ogn_python.collect.takeoff_landings import update_entries as takeoff_update_entries
 
 from ogn_python.collect.logbook import update_entries as logbook_update_entries
 from ogn_python.collect.logbook import update_max_altitudes as logbook_update_max_altitudes
 
-from ogn_python.collect.database import import_ddb
+from ogn_python.collect.database import import_ddb as device_infos_import_ddb
 from ogn_python.collect.database import update_country_code as receivers_update_country_code
 
 from ogn_python import db
@@ -22,7 +22,7 @@ def update_takeoff_landings():
     """Compute takeoffs and landings."""
 
     today = datetime.datetime.today()
-    update_takeoff_landings(session=db.session, date=today, logger=logger)
+    takeoff_update_entries(session=db.session, date=today, logger=logger)
 
 
 @celery.task(name='update_logbook_entries')
@@ -34,7 +34,7 @@ def update_logbook_entries():
 
 
 @celery.task(name='update_logbook_max_altitude')
-def update_logbook_max_altitude(session, logger=None):
+def update_logbook_max_altitude():
     """Add max altitudes in logbook when flight is complete (takeoff and landing)."""
 
     logbook_update_max_altitudes(session=db.session, logger=logger)
@@ -44,7 +44,7 @@ def update_logbook_max_altitude(session, logger=None):
 def import_ddb():
     """Import registered devices from the DDB."""
 
-    import_ddb(session=db.session, logger=logger)
+    device_infos_import_ddb(session=db.session, logger=logger)
 
 
 @celery.task(name='update_receivers_country_code')
diff --git a/ogn_python/collect/logbook.py b/ogn_python/collect/logbook.py
index 0a7d83b..65eb265 100644
--- a/ogn_python/collect/logbook.py
+++ b/ogn_python/collect/logbook.py
@@ -166,7 +166,7 @@ def update_max_altitudes(session, logger=None):
         .group_by(Logbook.id) \
         .subquery()
 
-    update_logbook = app.session.query(Logbook) \
+    update_logbook = session.query(Logbook) \
         .filter(Logbook.id == max_altitudes.c.id) \
         .update({
             Logbook.max_altitude: max_altitudes.c.max_altitude},
diff --git a/ogn_python/collect/takeoff_landings.py b/ogn_python/collect/takeoff_landings.py
index 3a62f17..7f4049a 100644
--- a/ogn_python/collect/takeoff_landings.py
+++ b/ogn_python/collect/takeoff_landings.py
@@ -10,7 +10,7 @@ from ogn_python.utils import date_to_timestamps
 from ogn_python import app
 
 
-def update_takeoff_landings(session, date, logger=None):
+def update_entries(session, date, logger=None):
     """Compute takeoffs and landings."""
 
     if logger is None:
diff --git a/ogn_python/commands/logbook.py b/ogn_python/commands/logbook.py
index 1899b91..0b7ee4d 100644
--- a/ogn_python/commands/logbook.py
+++ b/ogn_python/commands/logbook.py
@@ -3,8 +3,8 @@ import click
 
 from datetime import datetime
 
-from ogn_python.collect.logbook import update_entries
-from ogn_python.collect.takeoff_landings import update_takeoff_landings
+from ogn_python.collect.logbook import update_entries as logbook_update_entries
+from ogn_python.collect.takeoff_landings import update_entries as takeoff_landings_update_entries
 from ogn_python.model import Airport, Logbook
 from sqlalchemy.sql import func
 from tqdm import tqdm
@@ -28,7 +28,7 @@ def compute_takeoff_landing(start, end):
     pbar = tqdm(days)
     for single_date in pbar:
         pbar.set_description(datetime.strftime(single_date, '%Y-%m-%d'))
-        result = update_takeoff_landings(session=db.session, date=single_date)
+        result = takeoff_landings_update_entries(session=db.session, date=single_date)
 
 
 @user_cli.command('compute_logbook')
@@ -42,7 +42,7 @@ def compute_logbook(start, end):
     pbar = tqdm(days)
     for single_date in pbar:
         pbar.set_description(single_date.strftime('%Y-%m-%d'))
-        result = update_entries(session=db.session, date=single_date)
+        result = logbook_update_entries(session=db.session, date=single_date)
 
 
 @user_cli.command('show')