Horizontal well drilling and multi-stage hydraulic fracturing are key technologies for the development of shale gas reservoirs.Instantaneous acquisition of hydraulic fracture parameters is crucial for evaluating fract...Horizontal well drilling and multi-stage hydraulic fracturing are key technologies for the development of shale gas reservoirs.Instantaneous acquisition of hydraulic fracture parameters is crucial for evaluating fracturing effectiveness,optimizing processes,and predicting gas productivity.This paper establishes a transient flow model for shale gas wells based on the boundary element method,achieving the characterization of stimulated reservoir volume for a single stage.By integrating pressure monitoring data following the pumping shut-in period of hydraulic fracturing for well testing interpretation,a workflow for inverting fracture parameters of shale gas wells is established.This new method eliminates the need for prolonged production testing and can interpret parameters of individual hydraulic fracture segments,offering significant advantages over the conventional pressure transient analysismethod.The practical application of thismethodology was conducted on 10 shale gaswellswithin the Changning shale gas block of Sichuan,China.The results show a high correlation between the interpreted single-stage total length and surface area of hydraulic fractures and the outcomes of gas production profile tests.Additionally,significant correlations are observed between these parameters and cluster number,horizontal stress difference,and natural fracture density.This demonstrates the effectiveness of the proposed fracture parameter inversion method and the feasibility of field application.The findings of this study aim to provide solutions and references for the inversion of fracture parameters in shale gas wells.展开更多
As flow environment is poor in low permeability reservoirs, wells are always fractured in order to gain better economic benefits. Well testing analysis is very necessary for fracturing wells. However, available test a...As flow environment is poor in low permeability reservoirs, wells are always fractured in order to gain better economic benefits. Well testing analysis is very necessary for fracturing wells. However, available test analysis methods are of slow fitting speed and low fitting precision. In this paper, we first use a comprehensive evaluation method of analytical well testing, numerical well testing and well testing design. Many dynamic parameters such as fracture length, fracture conductivity, skin factor, etc are obtained. An example to illustrate accurate results of this method is given.展开更多
Several key issues related to ductility and fracture toughness limiting the application of intermetallics were discussed. Progress made in resolving some of the issues was discussed. The paper addresses design methodo...Several key issues related to ductility and fracture toughness limiting the application of intermetallics were discussed. Progress made in resolving some of the issues was discussed. The paper addresses design methodology for low defect tolerant materials. Impact resistance of NiAl under engine simulative conditions has been studied. The impact test results demonstrated a need for materials possessing improved impact resistance for turbine blade and vane applications. Some of the production implementation issues were also discussed.展开更多
In recent years, the Vehicle-to-Vehicle(V2V) communication system has been considered one of the most promising technologies to build a much safer and more efficient transportation system. Both simulation and field te...In recent years, the Vehicle-to-Vehicle(V2V) communication system has been considered one of the most promising technologies to build a much safer and more efficient transportation system. Both simulation and field test have been extensively performed to evaluate the performance of the V2V communication system. However,most of the evaluation methods are communication-based, and although in a transportation environment, lack a V2V application-oriented analysis. In this study, we conducted real-world tests and built an application-oriented evaluation model. The experiments were classified into four scenarios: static, following, face 2 face, and crossing vertically, which almost covered all the V2V communication patterns on the road. Under these scenarios, we conducted experiments and built a probability model to evaluate the performance of 802.11p and LTE-V in safetyrelated applications. Consequently, we found out that improvements are still needed in Non-Line-of-Sight scenarios.展开更多
目的探讨医学汉语进阶学习与评测设计在来华医学留学生医学汉语水平考试(Medical Chinese Test,MCT)实践中的应用效果。方法2022年9月—2023年7月,以2018级秋季5~8班130名医学留学生为教学研究对象,通过问卷调查评估留学生医学汉语的学...目的探讨医学汉语进阶学习与评测设计在来华医学留学生医学汉语水平考试(Medical Chinese Test,MCT)实践中的应用效果。方法2022年9月—2023年7月,以2018级秋季5~8班130名医学留学生为教学研究对象,通过问卷调查评估留学生医学汉语的学习和测评应采用从低阶中介语至高阶单语的模式,以配合双语学习者的渐进过程。结果该套学习与测评框架让学习者对源语言理解、中介语言解码、目标语言考核评测结果、学习者双语能力与专业知识学习方面均有提升。观察组学生自学能力、学习兴趣、进阶效果满意度分别为84.6%、83.1%、86.2%,观察组对该套医学汉语进阶学习与评测设计框架整体认可度高。结论该医学汉语进阶学习与评测设计框架在医学汉语学习与评测中有很好的教学效果。展开更多
基金funded by the Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance,grant numbers“2020CX020202,2020CX030202 and 2020CX010403”.
文摘Horizontal well drilling and multi-stage hydraulic fracturing are key technologies for the development of shale gas reservoirs.Instantaneous acquisition of hydraulic fracture parameters is crucial for evaluating fracturing effectiveness,optimizing processes,and predicting gas productivity.This paper establishes a transient flow model for shale gas wells based on the boundary element method,achieving the characterization of stimulated reservoir volume for a single stage.By integrating pressure monitoring data following the pumping shut-in period of hydraulic fracturing for well testing interpretation,a workflow for inverting fracture parameters of shale gas wells is established.This new method eliminates the need for prolonged production testing and can interpret parameters of individual hydraulic fracture segments,offering significant advantages over the conventional pressure transient analysismethod.The practical application of thismethodology was conducted on 10 shale gaswellswithin the Changning shale gas block of Sichuan,China.The results show a high correlation between the interpreted single-stage total length and surface area of hydraulic fractures and the outcomes of gas production profile tests.Additionally,significant correlations are observed between these parameters and cluster number,horizontal stress difference,and natural fracture density.This demonstrates the effectiveness of the proposed fracture parameter inversion method and the feasibility of field application.The findings of this study aim to provide solutions and references for the inversion of fracture parameters in shale gas wells.
文摘As flow environment is poor in low permeability reservoirs, wells are always fractured in order to gain better economic benefits. Well testing analysis is very necessary for fracturing wells. However, available test analysis methods are of slow fitting speed and low fitting precision. In this paper, we first use a comprehensive evaluation method of analytical well testing, numerical well testing and well testing design. Many dynamic parameters such as fracture length, fracture conductivity, skin factor, etc are obtained. An example to illustrate accurate results of this method is given.
文摘Several key issues related to ductility and fracture toughness limiting the application of intermetallics were discussed. Progress made in resolving some of the issues was discussed. The paper addresses design methodology for low defect tolerant materials. Impact resistance of NiAl under engine simulative conditions has been studied. The impact test results demonstrated a need for materials possessing improved impact resistance for turbine blade and vane applications. Some of the production implementation issues were also discussed.
基金supported in part by the National Natural Science Foundation of China(No.61673233)Beijing Municipal Science and Technology Program(No.D15110900280000)+1 种基金subsidized by the standardization and new model for intelligent manufacture:Research and Test Platform of System and Communication Standardization for Intelligent and Connected Vehicle(No.2016ZXFB06002)Shanghai International Automobile City
文摘In recent years, the Vehicle-to-Vehicle(V2V) communication system has been considered one of the most promising technologies to build a much safer and more efficient transportation system. Both simulation and field test have been extensively performed to evaluate the performance of the V2V communication system. However,most of the evaluation methods are communication-based, and although in a transportation environment, lack a V2V application-oriented analysis. In this study, we conducted real-world tests and built an application-oriented evaluation model. The experiments were classified into four scenarios: static, following, face 2 face, and crossing vertically, which almost covered all the V2V communication patterns on the road. Under these scenarios, we conducted experiments and built a probability model to evaluate the performance of 802.11p and LTE-V in safetyrelated applications. Consequently, we found out that improvements are still needed in Non-Line-of-Sight scenarios.
文摘目的探讨医学汉语进阶学习与评测设计在来华医学留学生医学汉语水平考试(Medical Chinese Test,MCT)实践中的应用效果。方法2022年9月—2023年7月,以2018级秋季5~8班130名医学留学生为教学研究对象,通过问卷调查评估留学生医学汉语的学习和测评应采用从低阶中介语至高阶单语的模式,以配合双语学习者的渐进过程。结果该套学习与测评框架让学习者对源语言理解、中介语言解码、目标语言考核评测结果、学习者双语能力与专业知识学习方面均有提升。观察组学生自学能力、学习兴趣、进阶效果满意度分别为84.6%、83.1%、86.2%,观察组对该套医学汉语进阶学习与评测设计框架整体认可度高。结论该医学汉语进阶学习与评测设计框架在医学汉语学习与评测中有很好的教学效果。
