Parker R L.、Oldenburg D W.提出密度界面与磁性界面的正反演法,该方法在频率域计算,计算速度快,是一种连续界面正反演方法。但是受到方法以及资料的限制,前人运用视磁化强度填图法时通常采用单界面无限延深或水平双界面磁性体模型进...Parker R L.、Oldenburg D W.提出密度界面与磁性界面的正反演法,该方法在频率域计算,计算速度快,是一种连续界面正反演方法。但是受到方法以及资料的限制,前人运用视磁化强度填图法时通常采用单界面无限延深或水平双界面磁性体模型进行反演计算,在地形(或磁性界面)起伏较大的地区往往得不到理想效果。针对这一问题,提出一种起伏双界面模型快速视磁化强度填图的新思路,即结合功率谱分析法反演上下起伏界面深度约束下的快速视磁化强度填图。理论模型计算结果说明,功率谱分析约束下的Parker法视磁化强度填图双界面起伏模型相较于水平界面模型提高了反演结果的精度。将该方法应用于小秦岭地区,圈定了与钼、金成矿密切相关的隐伏中生代花岗岩体11个,预测了成矿有利区域,为后期找矿工作提供了地球物理依据。展开更多
<p> <span style="font-family:Verdana;">To address the drawbacks of the traditional Parker test in multivariate linear</span><span style="font-family:;" "=""> ...<p> <span style="font-family:Verdana;">To address the drawbacks of the traditional Parker test in multivariate linear</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">models:</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">the process is cumbersome and computationally intensive,</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">we propose a new heteroscedasticity test.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">A new heteroskedasticity test is proposed using the fitted values of the samples as new explanatory variables, reconstructing the regression model, and giving a new heteroskedasticity test based on the significance test of the coefficients, it is also compared with the existing Parker test which is improved using the principal component idea. Numerical simulations and empirical analyses show that the improved Parker test with the fitted values of the samples proposed in this paper is superior.</span> </p>展开更多
Purpose: During oral fiberoptic intubation, advancement of an endotracheal tube (ETT) into the trachea is occasionally impeded by laryngeal structures. The curved flex tip Parker ETT has been shown to improve the like...Purpose: During oral fiberoptic intubation, advancement of an endotracheal tube (ETT) into the trachea is occasionally impeded by laryngeal structures. The curved flex tip Parker ETT has been shown to improve the likelihood of successful advancement as opposed to a standard ETT that is advanced in neutral orientation. However, a Parker tube has not been compared to a standard ETT oriented 90° counterclockwise from the neutral position. We hypothesize that fiber-optically-guided advancement of an ETT into the trachea will be more successful when using a Parker tube than a 90° counterclockwise-oriented standard ETT. Methods: This unblinded, randomized controlled trial compares the rate of successful advancement of a fiberoptically-guided endotracheal tube into the trachea. Two groups of randomly assigned patients with non-difficult airways are compared: a Parker flex-tip tube (Parker Group;n = 57) versus a standard ETT oriented 90° counterclockwise (Standard Group;n = 58). Our primary outcome is the first pass success rate of advanceing the ETT into the trachea. Results: First pass success occurred in 48 of 57 (84%) patients in the Parker Group vs. 39 of 58 (67%) of patients in the Standard Group (p = 0.0497). Conclusion: When advancing an ETT over an oral fiberoptic scope and into the trachea, a Parker curved flex tip ETT is statistically more likely to be placed successfully on the first pass than is a standard ETT oriented 90° counterclockwise.展开更多
文摘Parker R L.、Oldenburg D W.提出密度界面与磁性界面的正反演法,该方法在频率域计算,计算速度快,是一种连续界面正反演方法。但是受到方法以及资料的限制,前人运用视磁化强度填图法时通常采用单界面无限延深或水平双界面磁性体模型进行反演计算,在地形(或磁性界面)起伏较大的地区往往得不到理想效果。针对这一问题,提出一种起伏双界面模型快速视磁化强度填图的新思路,即结合功率谱分析法反演上下起伏界面深度约束下的快速视磁化强度填图。理论模型计算结果说明,功率谱分析约束下的Parker法视磁化强度填图双界面起伏模型相较于水平界面模型提高了反演结果的精度。将该方法应用于小秦岭地区,圈定了与钼、金成矿密切相关的隐伏中生代花岗岩体11个,预测了成矿有利区域,为后期找矿工作提供了地球物理依据。
文摘<p> <span style="font-family:Verdana;">To address the drawbacks of the traditional Parker test in multivariate linear</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">models:</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">the process is cumbersome and computationally intensive,</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">we propose a new heteroscedasticity test.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">A new heteroskedasticity test is proposed using the fitted values of the samples as new explanatory variables, reconstructing the regression model, and giving a new heteroskedasticity test based on the significance test of the coefficients, it is also compared with the existing Parker test which is improved using the principal component idea. Numerical simulations and empirical analyses show that the improved Parker test with the fitted values of the samples proposed in this paper is superior.</span> </p>
文摘Purpose: During oral fiberoptic intubation, advancement of an endotracheal tube (ETT) into the trachea is occasionally impeded by laryngeal structures. The curved flex tip Parker ETT has been shown to improve the likelihood of successful advancement as opposed to a standard ETT that is advanced in neutral orientation. However, a Parker tube has not been compared to a standard ETT oriented 90° counterclockwise from the neutral position. We hypothesize that fiber-optically-guided advancement of an ETT into the trachea will be more successful when using a Parker tube than a 90° counterclockwise-oriented standard ETT. Methods: This unblinded, randomized controlled trial compares the rate of successful advancement of a fiberoptically-guided endotracheal tube into the trachea. Two groups of randomly assigned patients with non-difficult airways are compared: a Parker flex-tip tube (Parker Group;n = 57) versus a standard ETT oriented 90° counterclockwise (Standard Group;n = 58). Our primary outcome is the first pass success rate of advanceing the ETT into the trachea. Results: First pass success occurred in 48 of 57 (84%) patients in the Parker Group vs. 39 of 58 (67%) of patients in the Standard Group (p = 0.0497). Conclusion: When advancing an ETT over an oral fiberoptic scope and into the trachea, a Parker curved flex tip ETT is statistically more likely to be placed successfully on the first pass than is a standard ETT oriented 90° counterclockwise.
