The underbalanced drilling has been widely used due to its advantages of high drilling efficiency and low cost etc., especially for hard formation drilling. These advantages, however, are closely related to the stress...The underbalanced drilling has been widely used due to its advantages of high drilling efficiency and low cost etc., especially for hard formation drilling. These advantages, however, are closely related to the stress state of the bottom-hole rock; therefore, it is significant to research the stress distribution of bottom-hole rock for the correct understanding of the mechanism of rock fragmentation and high penetration rate. The stress condition of bottom-hole rock is very complicated while under the co-action of overburden pressure, horizontal in-situ stresses, drilling mud pressure, pore pressure and temperature etc. In this paper, the fully coupled simulation model is established and the effects of overburden pressure, horizontal in-situ stresses, drilling mud pressure, pore pressure and temperature on stress distribution of bottom-hole rock are studied. The research shows that： in air drilling, as the well depth increases, the more easily the bottom-hole rock is broken; the mud pressure has a great effect on the bottom hole rock. The bigger the mud pressure is, the more difficult to break the bottom-hole rock; the max principle stress of the bottom-hole increased with the increasing of mud pressure, well depth and temperature difference. The bottom-hole rock can be divided into 3 regions respectively according to the stress state, 3 direction stretch zone, 2 direction compression area and 3 direction compression zone; the corresponding fragmentation degree of difficulty is easily, normally and hardly.展开更多
目的调查口腔颌面恶性肿瘤患者术后留置人工气道患者呛咳反射的发生情况和影响因素,并构建风险预测模型。方法2021年8月至2023年8月,采用便利抽样法选取2所三级甲等医院收治的口腔颌面恶性肿瘤术后留置人工气道患者150例为研究对象,采...目的调查口腔颌面恶性肿瘤患者术后留置人工气道患者呛咳反射的发生情况和影响因素,并构建风险预测模型。方法2021年8月至2023年8月,采用便利抽样法选取2所三级甲等医院收治的口腔颌面恶性肿瘤术后留置人工气道患者150例为研究对象,采用自制调查问卷对其进行纵向研究,了解其发生呛咳反射的影响因素,构建风险预测模型,并分析COX回归模型对口腔颌面恶性肿瘤患者术后留置人工气道患者发生呛咳反射的预测价值。结果口腔颌面恶性肿瘤患者术后留置人工气道患者呛咳反射发生率为31.33%;吸烟史、术前体位训练、卧位角度、应用舒芬太尼、术前放疗是口腔颌面恶性肿瘤术后留置人工气道患者呛咳反射发生的独立影响因素(均P<0.05);根据多因素COX回归分析,建立预测模型,经验证,曲线下面积(area under curve,AUC)为0.949,具有较好的预测价值。结论吸烟史、术前体位训练、卧位角度等均为口腔颌面恶性肿瘤患者术后留置人工气道患者发生呛咳反射的影响因素,COX回归模型能准确预测呛咳反射发生情况,护理人员可据此制订有效的干预措施。展开更多
基金Projects(U1562212,51525404)supported by the National Natural Science Foundation of ChinaProject(JYBFX-YQ-1)supported by the Research Project of Key Laboratory Machinery and Power Machinery(Xihua University),Ministry of Education,China
文摘The underbalanced drilling has been widely used due to its advantages of high drilling efficiency and low cost etc., especially for hard formation drilling. These advantages, however, are closely related to the stress state of the bottom-hole rock; therefore, it is significant to research the stress distribution of bottom-hole rock for the correct understanding of the mechanism of rock fragmentation and high penetration rate. The stress condition of bottom-hole rock is very complicated while under the co-action of overburden pressure, horizontal in-situ stresses, drilling mud pressure, pore pressure and temperature etc. In this paper, the fully coupled simulation model is established and the effects of overburden pressure, horizontal in-situ stresses, drilling mud pressure, pore pressure and temperature on stress distribution of bottom-hole rock are studied. The research shows that： in air drilling, as the well depth increases, the more easily the bottom-hole rock is broken; the mud pressure has a great effect on the bottom hole rock. The bigger the mud pressure is, the more difficult to break the bottom-hole rock; the max principle stress of the bottom-hole increased with the increasing of mud pressure, well depth and temperature difference. The bottom-hole rock can be divided into 3 regions respectively according to the stress state, 3 direction stretch zone, 2 direction compression area and 3 direction compression zone; the corresponding fragmentation degree of difficulty is easily, normally and hardly.
文摘目的调查口腔颌面恶性肿瘤患者术后留置人工气道患者呛咳反射的发生情况和影响因素,并构建风险预测模型。方法2021年8月至2023年8月,采用便利抽样法选取2所三级甲等医院收治的口腔颌面恶性肿瘤术后留置人工气道患者150例为研究对象,采用自制调查问卷对其进行纵向研究,了解其发生呛咳反射的影响因素,构建风险预测模型,并分析COX回归模型对口腔颌面恶性肿瘤患者术后留置人工气道患者发生呛咳反射的预测价值。结果口腔颌面恶性肿瘤患者术后留置人工气道患者呛咳反射发生率为31.33%;吸烟史、术前体位训练、卧位角度、应用舒芬太尼、术前放疗是口腔颌面恶性肿瘤术后留置人工气道患者呛咳反射发生的独立影响因素(均P<0.05);根据多因素COX回归分析,建立预测模型,经验证,曲线下面积(area under curve,AUC)为0.949,具有较好的预测价值。结论吸烟史、术前体位训练、卧位角度等均为口腔颌面恶性肿瘤患者术后留置人工气道患者发生呛咳反射的影响因素,COX回归模型能准确预测呛咳反射发生情况,护理人员可据此制订有效的干预措施。
