MATLAB software and optimal complete subgraph algorithm were used to extract and reveal the microsatellite distribution features in the complete genomes of the tobacco vein clearing virus （NC-003 378.1） from the NCB...MATLAB software and optimal complete subgraph algorithm were used to extract and reveal the microsatellite distribution features in the complete genomes of the tobacco vein clearing virus （NC-003 378.1） from the NCBI database.The results showed that the repetitions number and their location of the N-base group has been extracted and displayed.The largest repetitions of N-base group in the complete genomes of the tobacco vein clearing virus was decreased as the exponential function with the increasing of N.The method used in this study could be applied to the extraction and revealing of the microsatellite distribution features in the complete genomes of other viruses,thereby provided a basis for the research of the structure and the law of function,inheritance and variation by the using of the microsatellite distribution features.展开更多
Effective completion design in hydraulic fracturing(HF)is crucial for optimizing production in unconventional reservoirs.Traditional geometric designs often fail to account for geological and engineering heterogeneity...Effective completion design in hydraulic fracturing(HF)is crucial for optimizing production in unconventional reservoirs.Traditional geometric designs often fail to account for geological and engineering heterogeneity,leading to suboptimal stimulation.This study introduces a mechanism-guided data-driven model for optimized completion design that covers the entire process from sweet spot evaluation to stage and cluster optimization.For geological sweet spot evaluation,a mechanism-guided weighted K-medoids clustering model was developed by assigning weights to petrophysical parameters based on their correlation with production profiles.Engineering sweet spots were characterized using bottomhole mechanical specific energy(MSEb)and minimum horizontal in-situ stress(Shmin).The completion design optimization employed dynamic programming and a hybrid multi-objective optimization approach(NSGA-II),integrating geological and engineering sweet spots with operational constraints.The study showed a positive correlation between high-quality geological sweet spots and production(average correlation coefficient of 0.34),and a negative correlation between fluid allocation and engineering sweet spots(correlation coefficient of−0.46).Field application in the Jimsar Sag,Xinjiang,demonstrated that the proposed model significantly outperforms traditional geometric designs.Test wells showed an average 186%increase in cumulative production per 100 m over three months compared to conventional wells.The key findings of this work provide a novel technical pathway for optimized completion design of unconventional reservoirs with significant engineering applicability.展开更多
A new first-order optimality condition for the basis pursuit denoise （BPDN） problem is derived. This condition provides a new approach to choose the penalty param- eters adaptively for a fixed point iteration algori...A new first-order optimality condition for the basis pursuit denoise （BPDN） problem is derived. This condition provides a new approach to choose the penalty param- eters adaptively for a fixed point iteration algorithm. Meanwhile, the result is extended to matrix completion which is a new field on the heel of the compressed sensing. The numerical experiments of sparse vector recovery and low-rank matrix completion show validity of the theoretic results.展开更多
Founded in 1978, the Zhejiang Machinery Equipment Import & Export Corporation is an industrial and trading company engaged in the import and export business of machinery, electronics and instruments. Since 1980, w...Founded in 1978, the Zhejiang Machinery Equipment Import & Export Corporation is an industrial and trading company engaged in the import and export business of machinery, electronics and instruments. Since 1980, when is was granted self-operational rights, the company has increased year by year in terms of export volume, with its management improving and economic returns steadily rising. In 1995, its import and export volume hit US$119.展开更多
基金Supported by the Eleventh Five-year Development Planning Project for Instructional Science in Hubei Province (2006B131)~~
文摘MATLAB software and optimal complete subgraph algorithm were used to extract and reveal the microsatellite distribution features in the complete genomes of the tobacco vein clearing virus （NC-003 378.1） from the NCBI database.The results showed that the repetitions number and their location of the N-base group has been extracted and displayed.The largest repetitions of N-base group in the complete genomes of the tobacco vein clearing virus was decreased as the exponential function with the increasing of N.The method used in this study could be applied to the extraction and revealing of the microsatellite distribution features in the complete genomes of other viruses,thereby provided a basis for the research of the structure and the law of function,inheritance and variation by the using of the microsatellite distribution features.
基金supported by the National Natural Science Foundation of China(Grant/Award Nos.:52310001009 and 52122401).
文摘Effective completion design in hydraulic fracturing(HF)is crucial for optimizing production in unconventional reservoirs.Traditional geometric designs often fail to account for geological and engineering heterogeneity,leading to suboptimal stimulation.This study introduces a mechanism-guided data-driven model for optimized completion design that covers the entire process from sweet spot evaluation to stage and cluster optimization.For geological sweet spot evaluation,a mechanism-guided weighted K-medoids clustering model was developed by assigning weights to petrophysical parameters based on their correlation with production profiles.Engineering sweet spots were characterized using bottomhole mechanical specific energy(MSEb)and minimum horizontal in-situ stress(Shmin).The completion design optimization employed dynamic programming and a hybrid multi-objective optimization approach(NSGA-II),integrating geological and engineering sweet spots with operational constraints.The study showed a positive correlation between high-quality geological sweet spots and production(average correlation coefficient of 0.34),and a negative correlation between fluid allocation and engineering sweet spots(correlation coefficient of−0.46).Field application in the Jimsar Sag,Xinjiang,demonstrated that the proposed model significantly outperforms traditional geometric designs.Test wells showed an average 186%increase in cumulative production per 100 m over three months compared to conventional wells.The key findings of this work provide a novel technical pathway for optimized completion design of unconventional reservoirs with significant engineering applicability.
基金supported by the National Natural Science Foundation of China(No.61271014)the Specialized Research Fund for the Doctoral Program of Higher Education(No.20124301110003)the Graduated Students Innovation Fund of Hunan Province(No.CX2012B238)
文摘A new first-order optimality condition for the basis pursuit denoise （BPDN） problem is derived. This condition provides a new approach to choose the penalty param- eters adaptively for a fixed point iteration algorithm. Meanwhile, the result is extended to matrix completion which is a new field on the heel of the compressed sensing. The numerical experiments of sparse vector recovery and low-rank matrix completion show validity of the theoretic results.
文摘Founded in 1978, the Zhejiang Machinery Equipment Import & Export Corporation is an industrial and trading company engaged in the import and export business of machinery, electronics and instruments. Since 1980, when is was granted self-operational rights, the company has increased year by year in terms of export volume, with its management improving and economic returns steadily rising. In 1995, its import and export volume hit US$119.
