In this study, we propose and compare stochastic variants of the extra-gradient alternating direction method, named the stochastic extra-gradient alternating direction method with Lagrangian function（SEGL） and the s...In this study, we propose and compare stochastic variants of the extra-gradient alternating direction method, named the stochastic extra-gradient alternating direction method with Lagrangian function（SEGL） and the stochastic extra-gradient alternating direction method with augmented Lagrangian function（SEGAL）, to minimize the graph-guided optimization problems, which are composited with two convex objective functions in large scale.A number of important applications in machine learning follow the graph-guided optimization formulation, such as linear regression, logistic regression, Lasso, structured extensions of Lasso, and structured regularized logistic regression. We conduct experiments on fused logistic regression and graph-guided regularized regression. Experimental results on several genres of datasets demonstrate that the proposed algorithm outperforms other competing algorithms, and SEGAL has better performance than SEGL in practical use.展开更多
井距是新井井位部署及老井井位调整的关键因素,井距与产量相关;对特低渗透油藏CO_2非混相驱井距与产量关系的研究很少。在经典油气两相渗流理论的基础上,考虑CO_2溶解于原油所产生的降黏作用及油相启动压力梯度,建立了一个一维油气两相...井距是新井井位部署及老井井位调整的关键因素,井距与产量相关;对特低渗透油藏CO_2非混相驱井距与产量关系的研究很少。在经典油气两相渗流理论的基础上,考虑CO_2溶解于原油所产生的降黏作用及油相启动压力梯度,建立了一个一维油气两相渗流数学模型。基于Buckley-Leverett非活塞驱替理论对饱和度方程进行求解,开发了井距计算软件,分析了生产压差、CO_2驱替前缘推进距离百分比、渗透率对井距与产量关系的影响。计算结果显示,产量越大,井距越小,井距变化的幅度也越小。在注气井近井带,油相黏度由1.5 m Pa·s降低到0.4 m Pa·s;在生产井近井带,油相黏度由1.5 m Pa·s降低到0.6 m Pa·s,CO_2对于原油的降黏幅度可以达到70%左右,从注气井到生产井,油相黏度逐渐升高。为特低渗透油藏CO_2非混相驱井距与产量关系研究提供了一种计算方法,绘制了井距与产量随不同参数变化的理论图版,方便油田应用。展开更多
基金supported by the National Natural Science Foundation of China(No.61303264)the National Key Research and Development Program of China(No.2016YFB1000401)
文摘In this study, we propose and compare stochastic variants of the extra-gradient alternating direction method, named the stochastic extra-gradient alternating direction method with Lagrangian function（SEGL） and the stochastic extra-gradient alternating direction method with augmented Lagrangian function（SEGAL）, to minimize the graph-guided optimization problems, which are composited with two convex objective functions in large scale.A number of important applications in machine learning follow the graph-guided optimization formulation, such as linear regression, logistic regression, Lasso, structured extensions of Lasso, and structured regularized logistic regression. We conduct experiments on fused logistic regression and graph-guided regularized regression. Experimental results on several genres of datasets demonstrate that the proposed algorithm outperforms other competing algorithms, and SEGAL has better performance than SEGL in practical use.
文摘井距是新井井位部署及老井井位调整的关键因素,井距与产量相关;对特低渗透油藏CO_2非混相驱井距与产量关系的研究很少。在经典油气两相渗流理论的基础上,考虑CO_2溶解于原油所产生的降黏作用及油相启动压力梯度,建立了一个一维油气两相渗流数学模型。基于Buckley-Leverett非活塞驱替理论对饱和度方程进行求解,开发了井距计算软件,分析了生产压差、CO_2驱替前缘推进距离百分比、渗透率对井距与产量关系的影响。计算结果显示,产量越大,井距越小,井距变化的幅度也越小。在注气井近井带,油相黏度由1.5 m Pa·s降低到0.4 m Pa·s;在生产井近井带,油相黏度由1.5 m Pa·s降低到0.6 m Pa·s,CO_2对于原油的降黏幅度可以达到70%左右,从注气井到生产井,油相黏度逐渐升高。为特低渗透油藏CO_2非混相驱井距与产量关系研究提供了一种计算方法,绘制了井距与产量随不同参数变化的理论图版,方便油田应用。
