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This paper aims to solve the technical problems such as poor drillability， large formation inclination， difficult well deflection control， and easy wall instability in the middle and deep Carboniferous and Permian hard formation in the Hashan area of Shengli western exploration area and realize the efficient exploration and benefit development of oil and gas reserves. Based on the current conventional drilling technology， the applicability and process optimization of segmented combined drilling technology were studied， and supporting technologies for speed acceleration and safety construction related to gas drilling were proposed for the Carboniferous and Permian hard formation of dolomitic rock and igneous rock， forming the regional construction standards. After the transformation from gas drilling to drilling fluid construction， the combined drilling technology of “gas drilling + ‘impregnated bit + turbine/high-speed screw’” was preferred. According to the formation characteristics， efficient impregnated bit series of different sizes were developed to achieve well deflection control and improve the rate of penetration. The combined drilling technology was successfully applied in Hashan3 and Hashan2 wells and achieved good results. During gas drilling， the rate of penetration in Well Hashan3 reached 5.2 m/h， more than three times faster than the conventional drilling method. During drilling fluid construction， the technology of “impregnated bit + turbine/high-speed screw” was adopted， and the formation inclination was 30°. The well deflection was well controlled， and the rate of penetration was close to 1 m/h， which showed a good regional application effect compared with conventional drilling technology. The field application shows that the combined drilling technology of “gas drilling + ‘impregnated bit + turbine/high-speed screw’” is an effective means to increase the speed and efficiency of middle and deep drilling in the Hashan area of Shengli west exploration area. However， the technology also has bottlenecks. Combined with the applicability research of particle impact drilling （PID） technology， it is suggested that the PID technology should be introduced and improved in the next step， so as to achieve speed and efficiency breakthrough in regional drilling.

In order to promote the strategic planning for the oil import security of China, relevant influencing factors were studied by integrating document coding with the Decision Making Trial and Evaluation Laboratory-Interpretative Structural Modeling(DEMATELISM). The current situation and challenges of oil import of China were introduced based on the 4A definition of energy security in terms of supply, transportation and price. Meanwhile, the analytical framework of oil import security was established and coupled with document coding method to define the factors that influence the oil import security of China, thus forming the category of code statistics at different levels. Besides, the interrelation and hierarchical structure of factors were analyzed by DEMATEL-ISM, and suggestions were put forward on the policies. The results show that oil import security is influenced directly by superficial factors, including the production and transportation capacity of oil, and fundamentally by underlying factors, such as the stage of economic development and the structure of energy consumption. In addition, the shallow and deep factors, including the oil policy agreement, the import channel pattern, the import source structure and the construction of emergency system, are the critical points of oil import security. Therefore, special attention should be paid to the above-mentioned factors. Generally, the research results could provide theoretical and methodological support for the oil import of petroleum companies and governments.

Abstract Background Since early 2022, patients with 2019 novel coronavirus (COVID-19) infection have increased rapidly in Shanghai, China. Nevertheless, there is no widely used unified rehabilitation treatment available for discharged patients with post-infection sequelae such as dyspnea, depression, and fatigue. To promote the rehabilitation of discharged patients, our team formulated Kangyi Qiangshen Gong exercise prescription on the basis of traditional Chinese medicine rehabilitation exercises (TCMRE). We designed a randomized controlled trial to evaluate the efficacy of rehabilitation and advantages of KQG for discharged patients with post-COVID-19 syndrome. Methods/design This is a parallel-design, two-arm, analyst assessor-blinded, randomized controlled trial. In total, 60 discharged patients with COVID-19 sequelae, aged from 20 to 80 years will be recruited and randomly assigned to the World Health Organization instructed breathing techniques (BT) group and the Kangyi Qiangshen Gong exercise prescription (KQG) group at a ratio of 1:1. The patients in the BT group will perform breathing techniques exercise, and the patients in the KQG group will perform KQG exercise. Both groups will perform exercises twice a day for 3 months. The primary outcome will be measured with the Modified Medical Research Council Dyspnea Scale, and the secondary outcomes will include the Modified Borg Scale, Fatigue Scale-14, Patient Health Questionnaire-9 Scale, Pittsburgh Sleep Quality Index, and the Respiratory Symptoms Scale. Clinical scales will be assessed at three points (pre-exercise, 3 months post-exercise, and 3 months follow-up). Adverse events will be recorded for safety assessment. Discussion This trial will serve high-quality evidence of the value of KQG for treating discharged patients with COVID-19 in rehabilitation period. Trial registration Chinese Clinical Trial Registry ChiCTR2200059504. Registered on 03 May 2022. Dissemination The results will be published in peer-reviewed journals and disseminated through the study’s website, and conferences.