This study is based on the sedimentation conditions, organic geochemistry, storage spaces, physical properties, lithology and gas content of the shale gas reservoirs in Longmaxi Formation of the Jiaoshiba area and the...This study is based on the sedimentation conditions, organic geochemistry, storage spaces, physical properties, lithology and gas content of the shale gas reservoirs in Longmaxi Formation of the Jiaoshiba area and the gas accumulation mode is summarized and then compared with that in northern America. The shale gas reservoirs in the Longmaxi Formation in Jiaoshiba have good geological conditions, great thickness of quality shales, high organic content, high gas content, good physical properties, suitable depth, good preservation conditions and good reservoir types. The quality shales at the bottom of the deep shelf are the main target interval for shale gas exploration and development. Shale gas in the Longmaxi Formation has undergone three main reservoiring stages：the early stage of hydrocarbon generation and compaction when shale gas reservoirs were first formed; the middle stage of deep burial and large-scale hydrocarbon generation, which caused the enrichment of reservoirs with shale gas; the late stage of uplift, erosion and fracture development when shale gas reservoirs were finally formed.展开更多
The stochastic fluctuation of renewable energy resources has significant impact on the stability of the power system with renewable generations and results in change in stability.Therefore,it is necessary to track the...The stochastic fluctuation of renewable energy resources has significant impact on the stability of the power system with renewable generations and results in change in stability.Therefore,it is necessary to track the changing stability of the power system with renewable generations,a task that can be performed online.This paper details the use of decision trees to predict multi-mode damping of power system integrating renewable generations with the help of wide-area measurements system(WAMS).Power systems with renewable source generation are complex with vast amounts of data being collected from WAMS.Decision trees(DTs)are employed as a means to handle vast quantities of wide-area information,which involves the mode damping information indicating the stability.A 16-generator,68-bus system with photovoltaic power generation and wind power generation is used as the test system.Remote signals obtained from phasor measurement units(PMUs)are employed as the input variables of DTs for predicting purposes.The simulation results demonstrate that the proposed predicting scheme is able to suggest the optimal course of action to remedy any near instability or unstable electromechanical oscillations even without prior knowledge of the varying output of the renewable source power.展开更多
Rare earth-doped fibres are a diode-pumped,solid-state laser architecture that is highly scalable in average power.The performance of pulsed fibre laser systems is restricted due to nonlinear effects.Hence,fibre desig...Rare earth-doped fibres are a diode-pumped,solid-state laser architecture that is highly scalable in average power.The performance of pulsed fibre laser systems is restricted due to nonlinear effects.Hence,fibre designs that allow for very large mode areas at high average powers with diffraction-limited beam quality are of enormous interest.Ytterbium-doped,rod-type,large-pitch fibres(LPF)enable extreme fibre dimensions,i.e.,effective single-mode fibres with mode sizes exceeding 100 times the wavelength of the guided radiation,by exploiting the novel concept of delocalisation of higher-order transverse modes.The non-resonant nature of the operating principle makes LPF suitable for high power extraction.This design allows for an unparalleled level of performance in pulsed fibre lasers.展开更多
基金supported by the Sinopec Key Project named Whole Evaluation on Shale Gas Exploration and Targets Optimization in Sichuan Basin and Its Marginal Areas
文摘This study is based on the sedimentation conditions, organic geochemistry, storage spaces, physical properties, lithology and gas content of the shale gas reservoirs in Longmaxi Formation of the Jiaoshiba area and the gas accumulation mode is summarized and then compared with that in northern America. The shale gas reservoirs in the Longmaxi Formation in Jiaoshiba have good geological conditions, great thickness of quality shales, high organic content, high gas content, good physical properties, suitable depth, good preservation conditions and good reservoir types. The quality shales at the bottom of the deep shelf are the main target interval for shale gas exploration and development. Shale gas in the Longmaxi Formation has undergone three main reservoiring stages：the early stage of hydrocarbon generation and compaction when shale gas reservoirs were first formed; the middle stage of deep burial and large-scale hydrocarbon generation, which caused the enrichment of reservoirs with shale gas; the late stage of uplift, erosion and fracture development when shale gas reservoirs were finally formed.
基金supported by the National Basic Research Program of China(973 Program)(No.2012CB215206)National Natural Science Foundation of China(No.51407071)+3 种基金the International Collaborative Project jointly Funded by the NSFC(No.51311122)Chinathe EPSRC,UKFundamental Research Funds for the Central Universities(No.2014QN18)China Postdoctoral Science Foundation(No.2014M550683).
文摘The stochastic fluctuation of renewable energy resources has significant impact on the stability of the power system with renewable generations and results in change in stability.Therefore,it is necessary to track the changing stability of the power system with renewable generations,a task that can be performed online.This paper details the use of decision trees to predict multi-mode damping of power system integrating renewable generations with the help of wide-area measurements system(WAMS).Power systems with renewable source generation are complex with vast amounts of data being collected from WAMS.Decision trees(DTs)are employed as a means to handle vast quantities of wide-area information,which involves the mode damping information indicating the stability.A 16-generator,68-bus system with photovoltaic power generation and wind power generation is used as the test system.Remote signals obtained from phasor measurement units(PMUs)are employed as the input variables of DTs for predicting purposes.The simulation results demonstrate that the proposed predicting scheme is able to suggest the optimal course of action to remedy any near instability or unstable electromechanical oscillations even without prior knowledge of the varying output of the renewable source power.
基金The research leading to these results received funding from the European Research Council under the European Union’s Seventh Framework Programme(FP7/2007-2013)/ERC Grant Agreement No.[240460]the Thuringian Ministry of Education,Science and Culture under contract PE203-2-1(MOFA)and contract B514-10061(Green Photonics).FJ acknowledges financial support from the Abbe School of Photonics.
文摘Rare earth-doped fibres are a diode-pumped,solid-state laser architecture that is highly scalable in average power.The performance of pulsed fibre laser systems is restricted due to nonlinear effects.Hence,fibre designs that allow for very large mode areas at high average powers with diffraction-limited beam quality are of enormous interest.Ytterbium-doped,rod-type,large-pitch fibres(LPF)enable extreme fibre dimensions,i.e.,effective single-mode fibres with mode sizes exceeding 100 times the wavelength of the guided radiation,by exploiting the novel concept of delocalisation of higher-order transverse modes.The non-resonant nature of the operating principle makes LPF suitable for high power extraction.This design allows for an unparalleled level of performance in pulsed fibre lasers.
