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广义岭型主相关估计的方差最优性
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作者 林昌盛 《数学理论与应用》 2009年第3期114-116,共3页
本文在回归系数的岭型主相关估计的基础上,提出了广义岭型主相关估计,进一步研究其在降维估计类中方差最优性。
关键词 线型回归模型 广义岭型主相关估计 方差 最优性
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“84办法”在特小流域洪峰流量计算中的应用 被引量:5
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作者 郑佳重 朱梅 +4 位作者 黄双双 王振龙 时召军 周迪 许良元 《南水北调与水利科技》 CAS CSCD 北大核心 2014年第6期63-65,69,共4页
“84办法”是安徽省水利部门在中小流域(10~300 km2)洪峰流量计算中的常用方法,但在特小流域中(<10km2)的应用较少.以安徽省马鞍山市雨山现代农业示范园内的防洪渠设计洪水分析计算为例,将“84办法”与特小流域中计算洪峰流量常... “84办法”是安徽省水利部门在中小流域(10~300 km2)洪峰流量计算中的常用方法,但在特小流域中(<10km2)的应用较少.以安徽省马鞍山市雨山现代农业示范园内的防洪渠设计洪水分析计算为例,将“84办法”与特小流域中计算洪峰流量常用的两种方法即中国水科院1958年推理公式法和中国公路科学研究所经验公式法进行比较、分析与讨论,认为“84办法”在特小流域洪峰流量计算中的应用是合理可行的. 展开更多
关键词 “84办法” 安徽省 中小流域 特小流域 洪峰流量 洪水分析计算 基本线型回归模型
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Optimal timing of staged percutaneous coronary intervention in ST-segment elevation myocardial infarction patients with multivessel disease 被引量:10
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作者 Xue-Dong ZHAO Guan-Qi ZHAO +4 位作者 Xiao WANG Shu-Tian SHI Wen ZHENG Rui-Feng GUO Shao-Ping NIE 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第5期356-362,共7页
Background Studies have shown that staged percutaneous coronary intervention (PCI) for non-culprit lesions is beneficial for prog- nosis of ST-segment elevation myocardial infarction (STEMI) patients with multives... Background Studies have shown that staged percutaneous coronary intervention (PCI) for non-culprit lesions is beneficial for prog- nosis of ST-segment elevation myocardial infarction (STEMI) patients with multivessel disease. However, the optimal timing of staged re- vascularization is still controversial. This study aimed to find the optimal timing of staged revascularization. Methods A total of 428 STEMI patients with multivessel disease who underwent primary PCI and staged PCI were included. According to the time interval between primary and staged PCI, patients were divided into three groups (〈 1 week, 1- weeks, and 2-12 weeks after primary PCI). The primary endpoint was major adverse cardiovascular events (MACE), a composite of all-cause death, non-fatal re-infarction, repeat revascularization, and stroke. Cox regression model was used to assess the association between staged PCI timing and risk of MACE. Results During the follow-up, 119 participants had MACEs. There was statistical difference in MACE incidence among the three groups (〈 1 week: 23.0%; 1-2 weeks: 33.0%; 2-12 weeks: 40.0%; P = 0.001). In the multivariable adjustment model, the timing interval of staged PCI ≤ 1 week and l-2 weeks were both significantly associated with a lower risk of MACE [hazard ratio (HR): 0.40, 95% confidence intervals (CI): 0.24-4).65; HR: 0.54, 95% CI: 0.3 lq3.93, respectively], mainly attributed to a lower risk of repeat revascularization (HR: 0.41, 95% CI: 0.24-0.70; HR: 0.36, 95% CI: 0.18-0.7), compared with a strategy of 2-12 weeks later of primary PCI. Conclusions The optimal timing of staged PCI for non-culprit vessels should be within two weeks after primary PCI for STEMI patients. 展开更多
关键词 Myocardial infarction Multivessel disease Non-culprit lesion Percutaneous coronary intervention TIMING
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Regression analysis of major parameters affecting the intensity of coal and gas outbursts in laboratory 被引量:7
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作者 Geng Jiabo Xu Jiang +3 位作者 Nie Wen Peng Shoujian Zhang Chaolin Luo Xiaohang 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第2期327-332,共6页
Estimating the intensity of outbursts of coal and gas is important as the intensity and frequency of outbursts of coal and gas tend to increase in deep mining. Fully understanding the major factors contributing to coa... Estimating the intensity of outbursts of coal and gas is important as the intensity and frequency of outbursts of coal and gas tend to increase in deep mining. Fully understanding the major factors contributing to coal and gas outbursts is significant in the evaluation of the intensity of the outburst. In this paper, we discuss the correlation between these major factors and the intensity of the outburst using Analysis of Variance(ANOVA) and Contingency Table Analysis(CTA). Regression analysis is used to evaluate the impact of these major factors on the intensity of outbursts based on physical experiments. Based on the evaluation, two simple models in terms of multiple linear and nonlinear regression were constructed for the prediction of the intensity of the outburst. The results show that the gas pressure and initial moisture in the coal mass could be the most significant factors compared to the weakest factor-porosity. The P values from Fisher's exact test in CTA are: moisture(0.019), geostress(0.290), porosity(0.650), and gas pressure(0.031). P values from ANOVA are moisture(0.094), geostress(0.077), porosity(0.420), and gas pressure(0.051). Furthermore, the multiple nonlinear regression model(RMSE: 3.870) is more accurate than the linear regression model(RMSE: 4.091). 展开更多
关键词 Coal and gas outburst Gas pressure Regression analysis ANOVA CTA
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