Group 1 - CNOOC Services Co., Ltd. has applied for a patent titled "Fault Diagnosis Method and Device for Subsea Blowout Preventer Hydraulic Control System," with publication number CN121277151A, and the application date is October 2025 [1] - The patent describes a method for diagnosing faults in subsea blowout preventer hydraulic control systems, which includes collecting operational data, processing it to create a dataset, and using a probabilistic slow feature analysis model to identify normal and fault samples [1] - The method employs synthetic minority oversampling techniques to generate synthetic samples from fault data, enhancing the dataset for training a fault diagnosis model using an attention deep belief network [1] Group 2 - CNOOC Services Co., Ltd. was established in 2001 and is located in Tianjin, primarily engaged in business services [2] - The company has a registered capital of 477,159.2 million RMB and has made investments in 11 enterprises, participated in 5,000 bidding projects, and holds 2634 patents [2] - Additionally, the company has 273 trademark registrations and 199 administrative licenses [2]