Certificate of Patent(A cutter for dredges with a structure that prevents foreig...

Certificate of Patent(Movable equipment cradle installed on barge)

Certificate of Patent(Transfer method after crushing of dredged clay soil)

Certificate of Patent(Bucket)

Certificate of Patent(Coastal reclamation unloading method for marine pollution ...

Certification of International Contractor(Dredging)

Certification of International Contractor(Earthworks)

Certification of International Contractor(Reinforced Concrete)

Certification of International Contractor(Underwater Works)

Certification of International Contractor(Scaffol;ding)

Certification of Construction Contractor(Water supply and sewage facility constr...

Certification of Construction Contractor(Civil/Architecture)