Class III tight oil reservoirs have low porosity and permeability,which are often responsible for low production rates and limited recovery.Extensive repeated fracturing is a well-known technique to fix some of these ...Class III tight oil reservoirs have low porosity and permeability,which are often responsible for low production rates and limited recovery.Extensive repeated fracturing is a well-known technique to fix some of these issues.With such methods,existing fractures are refractured,and/or new fractures are created to facilitate communication with natural fractures.This study explored how different refracturing methods affect horizontal well fracture networks,with a special focus on morphology and related fluid flow changes.In particular,the study relied on the unconventional fracture model(UFM).The evolution of fracture morphology and flow field after the initial fracturing were analyzed accordingly.The simulation results indicated that increased formation energy and reduced reservoir stress differences can promote fracture expansion.It was shown that the length of the fracture network,the width of the fracture network,and the complexity of the fracture can be improved,the oil drainage area can be increased,the distance of oil and gas seepage can be reduced,and the production of a single well can be significantly increased.展开更多
This paper introduces the selection and scheme demonstration of higher voltage class in Northwest ChinaPower Network, and conclusions made by main research institutes and experts’ comments.[
The existing Internet technologies and the original Internet design concept cannot meet the requirement of development, due to the fast development of the Internet, great changes of the Internet user groups and the tr...The existing Internet technologies and the original Internet design concept cannot meet the requirement of development, due to the fast development of the Internet, great changes of the Internet user groups and the tremendous transformation of the Internet external environment. The Internet is at a development crossroad; and its direction of development has attracted great attention from the world. On the other hand, the telecom industry is in a rather passive position as the result of the great impact the Internet technology has posted on it. The telecom industry has failed in defining its own developing direction and technology breakthrough; therefore, it is also at a crossroad. The development of both the Internet and the telecom networks will lead to the development of Next Generation Network (NGN) technologies. Industrial attention and research should be focused on the key NGN technologies, solutions to problems in the development of these technologies, and their commercialization in a short term.展开更多
The network integration provides users with a new network with long connection time and a high data rate when needed, but it also brings the defects of all the networks that integrate together into the integrated netw...The network integration provides users with a new network with long connection time and a high data rate when needed, but it also brings the defects of all the networks that integrate together into the integrated network. This will cause all kinds of existing and some new security problems in the operation of the integrated network. A complete protection based on recovery is proposed in the paper. It uses the public-key algorithm to authorize and private-key algorithm to encrypt the communicating data. This solution can provide the system with reliable security, and avoid Denial of Service (DoS) of the user. This solution has been proposed lately, and we should further identify the correct action of all the layers and figure out how to react when a legal node is framed by multiple malicious nodes.展开更多
To provide any subscriber from anywhere at anytime with services that have both secured Quality of Service(QoS) and simultaneous expansion of network coverage and communications capacity is a key problem that has to b...To provide any subscriber from anywhere at anytime with services that have both secured Quality of Service(QoS) and simultaneous expansion of network coverage and communications capacity is a key problem that has to be considered and solved in heterogeneous network convergence.Key technologies for a secured QoS and communications capacity analysis under heterogeneous environment are important subjects for research.Key technologies for a secured QoS are mainly on radio resource management algorithms covering Call Admission Control(CAC) algorithm,vertical handover algorithm,heterogeneous resource allocation algorithm and network selection algorithm.The applications of a novel multi-hop in heterogeneous convergence system serve the purposes of network coverage expansion,transmission power reduction,system communication capacity and throughput increase.展开更多
The innovations actually diffuse among social network nowadays.Individual heterogeneity,interactions between individuals and network topology influence a lot.We established a "double threshold" modified mode...The innovations actually diffuse among social network nowadays.Individual heterogeneity,interactions between individuals and network topology influence a lot.We established a "double threshold" modified model and took the number of neighbors,neighbors' adoption and the cost-benefit parameters as crucial influencing factors.The diffusion of DaLingTong(CDMA450)products in MeiShan city of SiChuan province during 2004 to 2007 has been used to verity the model on Matlab.The validation results fit the actual diffusion pattern of DaLingTong(CDMA450) products very well.The results indicate that there exists a "tipping point(threshold)" in the process of innovation diffusion.If the initial adoption quantity is larger than the tipping point,then the product will spread to a large portion of people,otherwise is will collapse to zero.The model can effectively predict the diffusion of new products,and can influence the diffusion process by changing the value of the parameters.展开更多
In this letter, the functional-link network (FLN), one of the latest model of neuralnetworks, was used to carry out a detailed QSAR analysis on the series compounds ofO-ethyl-O-aryl-N-isopropyl-phosphoramidothioates w...In this letter, the functional-link network (FLN), one of the latest model of neuralnetworks, was used to carry out a detailed QSAR analysis on the series compounds ofO-ethyl-O-aryl-N-isopropyl-phosphoramidothioates which have high herbicidal activity. FLNis a 2-layer network with simplified structure and has extremely quickened convergence withperfect performance of both fitting and predicting due to the appropriately enhanced展开更多
We have used chemical bond parameters and pattern recognition method to investigatethe regularities of the crystal type of alloy phase,and achieved good results.Theparameters used,however,are semi-empirical paramters,...We have used chemical bond parameters and pattern recognition method to investigatethe regularities of the crystal type of alloy phase,and achieved good results.Theparameters used,however,are semi-empirical paramters,which are not very strict fromtheoretical viewpoint.In this letter,we use the numbers describing atomic structure(thenumbers of valence electrons Z<sub>1</sub>,Z<sub>2</sub>,the principal quantum numbers of valence electrons n<sub>1</sub>,展开更多
基金the China Research and Pilot Test on Key Technology of Efficient Production of Changqing Tight Oil(Grant No.2021DJ2202).
文摘Class III tight oil reservoirs have low porosity and permeability,which are often responsible for low production rates and limited recovery.Extensive repeated fracturing is a well-known technique to fix some of these issues.With such methods,existing fractures are refractured,and/or new fractures are created to facilitate communication with natural fractures.This study explored how different refracturing methods affect horizontal well fracture networks,with a special focus on morphology and related fluid flow changes.In particular,the study relied on the unconventional fracture model(UFM).The evolution of fracture morphology and flow field after the initial fracturing were analyzed accordingly.The simulation results indicated that increased formation energy and reduced reservoir stress differences can promote fracture expansion.It was shown that the length of the fracture network,the width of the fracture network,and the complexity of the fracture can be improved,the oil drainage area can be increased,the distance of oil and gas seepage can be reduced,and the production of a single well can be significantly increased.
文摘This paper introduces the selection and scheme demonstration of higher voltage class in Northwest ChinaPower Network, and conclusions made by main research institutes and experts’ comments.[
文摘The existing Internet technologies and the original Internet design concept cannot meet the requirement of development, due to the fast development of the Internet, great changes of the Internet user groups and the tremendous transformation of the Internet external environment. The Internet is at a development crossroad; and its direction of development has attracted great attention from the world. On the other hand, the telecom industry is in a rather passive position as the result of the great impact the Internet technology has posted on it. The telecom industry has failed in defining its own developing direction and technology breakthrough; therefore, it is also at a crossroad. The development of both the Internet and the telecom networks will lead to the development of Next Generation Network (NGN) technologies. Industrial attention and research should be focused on the key NGN technologies, solutions to problems in the development of these technologies, and their commercialization in a short term.
文摘The network integration provides users with a new network with long connection time and a high data rate when needed, but it also brings the defects of all the networks that integrate together into the integrated network. This will cause all kinds of existing and some new security problems in the operation of the integrated network. A complete protection based on recovery is proposed in the paper. It uses the public-key algorithm to authorize and private-key algorithm to encrypt the communicating data. This solution can provide the system with reliable security, and avoid Denial of Service (DoS) of the user. This solution has been proposed lately, and we should further identify the correct action of all the layers and figure out how to react when a legal node is framed by multiple malicious nodes.
基金the National Basic Research Program of China("973"Program)under Grant No.2007CB310606the Specialized Foundation for the Achievements Transformation of Science and Technology in Jiangsu Province under Grant No.BA2006101
文摘To provide any subscriber from anywhere at anytime with services that have both secured Quality of Service(QoS) and simultaneous expansion of network coverage and communications capacity is a key problem that has to be considered and solved in heterogeneous network convergence.Key technologies for a secured QoS and communications capacity analysis under heterogeneous environment are important subjects for research.Key technologies for a secured QoS are mainly on radio resource management algorithms covering Call Admission Control(CAC) algorithm,vertical handover algorithm,heterogeneous resource allocation algorithm and network selection algorithm.The applications of a novel multi-hop in heterogeneous convergence system serve the purposes of network coverage expansion,transmission power reduction,system communication capacity and throughput increase.
基金ACKNOWLEDGEMENTS Project supported by the National Social Science Foundation of China （Grant No. 11BGL041）, Ministry of Education Humanities and Social Sciences General Project （12YJA630166）.
文摘The innovations actually diffuse among social network nowadays.Individual heterogeneity,interactions between individuals and network topology influence a lot.We established a "double threshold" modified model and took the number of neighbors,neighbors' adoption and the cost-benefit parameters as crucial influencing factors.The diffusion of DaLingTong(CDMA450)products in MeiShan city of SiChuan province during 2004 to 2007 has been used to verity the model on Matlab.The validation results fit the actual diffusion pattern of DaLingTong(CDMA450) products very well.The results indicate that there exists a "tipping point(threshold)" in the process of innovation diffusion.If the initial adoption quantity is larger than the tipping point,then the product will spread to a large portion of people,otherwise is will collapse to zero.The model can effectively predict the diffusion of new products,and can influence the diffusion process by changing the value of the parameters.
基金Project supported by the National Natural Science Foundation of China.
文摘In this letter, the functional-link network (FLN), one of the latest model of neuralnetworks, was used to carry out a detailed QSAR analysis on the series compounds ofO-ethyl-O-aryl-N-isopropyl-phosphoramidothioates which have high herbicidal activity. FLNis a 2-layer network with simplified structure and has extremely quickened convergence withperfect performance of both fitting and predicting due to the appropriately enhanced
文摘We have used chemical bond parameters and pattern recognition method to investigatethe regularities of the crystal type of alloy phase,and achieved good results.Theparameters used,however,are semi-empirical paramters,which are not very strict fromtheoretical viewpoint.In this letter,we use the numbers describing atomic structure(thenumbers of valence electrons Z<sub>1</sub>,Z<sub>2</sub>,the principal quantum numbers of valence electrons n<sub>1</sub>,
