Since July 2014,when the international oil price slumped,the upstream sector of global oil and gas industry has experienced a tough transformation phase lasting over two years.In terms of the development trend,the glo...Since July 2014,when the international oil price slumped,the upstream sector of global oil and gas industry has experienced a tough transformation phase lasting over two years.In terms of the development trend,the global upstream sector has demonstrated six characteristics since 2017:firstly,global upstream investment will probably demonstrate the trend of "touching the ground and rising again";secondly,upstream operating costs will continually decline;thirdly,more favorable finance and taxation clauses will be offered for some resources to be developed through foreign cooperation;fourthly,global oil and gas output will probably further increase;fifthly,upstream exploration efficiency is anticipated to steadily increase;and sixthly,upstream geological understandings,theory and technology will continue to advance.In accordance with the above-mentioned development trends,Chinese oil enterprises must be prepared in four aspects for future rejuvenation.Firstly,persistent upstream investment has to be guaranteed,particularly in the exploration field;secondly,upstream operation efficiency must be promoted through the enhancement of technical research;thirdly,overseas upstream property must be purchased within the "time window";and fourthly,reforms have to be carried out to realize transformation in the petroleum industry.展开更多
Significant progress has been made in distributed unmanned aerial vehicle(UAV)swarm exploration.In complex scenarios,existing methods typically rely on shared trajectory information for collision avoidance,but communi...Significant progress has been made in distributed unmanned aerial vehicle(UAV)swarm exploration.In complex scenarios,existing methods typically rely on shared trajectory information for collision avoidance,but communication timeliness issues may result in outdated trajectories being referenced when making collision avoidance decisions,preventing timely responses to the motion changes of other UAVs,thus elevating the collision risk.To address this issue,this paper proposes a new distributed UAV swarm exploration framework.First,we introduce an improved global exploration strategy that combines the exploration task requirements with the surrounding obstacle distribution to plan an efficient and safe coverage path.Secondly,we design a collision risk prediction method based on relative distance and relative velocity,which effectively assists UAVs in making timely collision avoidance decisions.Lastly,we propose a multi-objective local trajectory optimization function that considers the positions of UAVs and static obstacles,thereby planning safe flight trajectories.Extensive simulations and real-world experiments demonstrate that this framework enables safe and efficient exploration in complex environments.展开更多
The Keshen gas field is located in the central part of Kuqa foreland thrust belt in Tarim Basin,and is another large gas field discovered in Kuqa depression after Kela 2 gas field.Since the breakthrough in 2008,a numb...The Keshen gas field is located in the central part of Kuqa foreland thrust belt in Tarim Basin,and is another large gas field discovered in Kuqa depression after Kela 2 gas field.Since the breakthrough in 2008,a number of large and medium scale gas reservoirs including Keshen 2,Keshen 5 and Keshen 8 have been discovered,that are characterized by ultra depth,ultra-high pressure,ultra-low porosity,ultra-low permeability,high temperature and high pressure.With natural gas geological reserves of nearly trillion cubic meters and production capacity of nearly 5.5 billion cubic meters,the Keshen gas field is the main natural gas producing area in Tarim Oilfield.The Keshen gas field is located in a series of thrusting imbrication structures in the Kelasu structural belt of Kuqa foreland thrust belt.The salt roof structure,plastic rheology of salt beds and pre-salt faulted anticlinal structure constitute the large wedge-shaped thrust body.The thick delta sandstone of the Cretaceous Bashijike Formation is widely distributed,and it forms the superior reservoir-caprock combination with overlying Paleogene thick gypsum-salt bed.The deep Jurassic-Triassic oil and gas migrate vertically along fault system formed in Late Himalaya,break through the thick Cretaceous mudstone and move laterally along the fracture system of the pre-salt reservoirs,to form anticline and fault anticline high pressure reservoir groups.Through near ten years of studies,the three-dimensional seismic acquisition and processing technology for complex mountainous areas,extrusion salt-related structural modeling technology and fractured low-porosity sandstone reservoir evaluation technology have been established,which lay a foundation for realization of oil and gas exploration objectives.Logging acquisition and evaluation technology for high temperature,high pressure,ultra-deep and low-porosity sandstone gas reservoirs,and efficient development technology for fractured tight sandstone gas reservoirs have been developed,which provide a technical support for efficient exploration&development and rapid production of the Keshen gas field.展开更多
文摘Since July 2014,when the international oil price slumped,the upstream sector of global oil and gas industry has experienced a tough transformation phase lasting over two years.In terms of the development trend,the global upstream sector has demonstrated six characteristics since 2017:firstly,global upstream investment will probably demonstrate the trend of "touching the ground and rising again";secondly,upstream operating costs will continually decline;thirdly,more favorable finance and taxation clauses will be offered for some resources to be developed through foreign cooperation;fourthly,global oil and gas output will probably further increase;fifthly,upstream exploration efficiency is anticipated to steadily increase;and sixthly,upstream geological understandings,theory and technology will continue to advance.In accordance with the above-mentioned development trends,Chinese oil enterprises must be prepared in four aspects for future rejuvenation.Firstly,persistent upstream investment has to be guaranteed,particularly in the exploration field;secondly,upstream operation efficiency must be promoted through the enhancement of technical research;thirdly,overseas upstream property must be purchased within the "time window";and fourthly,reforms have to be carried out to realize transformation in the petroleum industry.
基金supported in part by the National Key Research and Development Program of China under Grant No.2022YFA1004700in part by the National Natural Science Foundation of China under Grant Nos.62301308,62305019,62371342,and 62071334+4 种基金in part by the Shanghai Municipal Science and Technology Major Project under Grant No.2021SHZDZX0100in part by the Shanghai Municipal Commission of Science and Technology Project under Grant No.19511132101in part by the Aeronautical Science Foundation of China under Grant No.20230007308001in part by the Fundamental Research Funds for the Central Universities under Grant No.22120210543in part by Tianjin Transportation Science and Technology Project under Grant No.2025-76.
文摘Significant progress has been made in distributed unmanned aerial vehicle(UAV)swarm exploration.In complex scenarios,existing methods typically rely on shared trajectory information for collision avoidance,but communication timeliness issues may result in outdated trajectories being referenced when making collision avoidance decisions,preventing timely responses to the motion changes of other UAVs,thus elevating the collision risk.To address this issue,this paper proposes a new distributed UAV swarm exploration framework.First,we introduce an improved global exploration strategy that combines the exploration task requirements with the surrounding obstacle distribution to plan an efficient and safe coverage path.Secondly,we design a collision risk prediction method based on relative distance and relative velocity,which effectively assists UAVs in making timely collision avoidance decisions.Lastly,we propose a multi-objective local trajectory optimization function that considers the positions of UAVs and static obstacles,thereby planning safe flight trajectories.Extensive simulations and real-world experiments demonstrate that this framework enables safe and efficient exploration in complex environments.
基金The work was supported by the National Science and Technology Major Project of China(No.2016ZX05003-004).
文摘The Keshen gas field is located in the central part of Kuqa foreland thrust belt in Tarim Basin,and is another large gas field discovered in Kuqa depression after Kela 2 gas field.Since the breakthrough in 2008,a number of large and medium scale gas reservoirs including Keshen 2,Keshen 5 and Keshen 8 have been discovered,that are characterized by ultra depth,ultra-high pressure,ultra-low porosity,ultra-low permeability,high temperature and high pressure.With natural gas geological reserves of nearly trillion cubic meters and production capacity of nearly 5.5 billion cubic meters,the Keshen gas field is the main natural gas producing area in Tarim Oilfield.The Keshen gas field is located in a series of thrusting imbrication structures in the Kelasu structural belt of Kuqa foreland thrust belt.The salt roof structure,plastic rheology of salt beds and pre-salt faulted anticlinal structure constitute the large wedge-shaped thrust body.The thick delta sandstone of the Cretaceous Bashijike Formation is widely distributed,and it forms the superior reservoir-caprock combination with overlying Paleogene thick gypsum-salt bed.The deep Jurassic-Triassic oil and gas migrate vertically along fault system formed in Late Himalaya,break through the thick Cretaceous mudstone and move laterally along the fracture system of the pre-salt reservoirs,to form anticline and fault anticline high pressure reservoir groups.Through near ten years of studies,the three-dimensional seismic acquisition and processing technology for complex mountainous areas,extrusion salt-related structural modeling technology and fractured low-porosity sandstone reservoir evaluation technology have been established,which lay a foundation for realization of oil and gas exploration objectives.Logging acquisition and evaluation technology for high temperature,high pressure,ultra-deep and low-porosity sandstone gas reservoirs,and efficient development technology for fractured tight sandstone gas reservoirs have been developed,which provide a technical support for efficient exploration&development and rapid production of the Keshen gas field.
