The assumption of homoscedasticity has received much attention in classical analysis of regression. Heteroscedasticity tests have been well studied in parametric and nonparametric regressions. The aim of this paper is...The assumption of homoscedasticity has received much attention in classical analysis of regression. Heteroscedasticity tests have been well studied in parametric and nonparametric regressions. The aim of this paper is to present a test of heteroscedasticity for nonlinear semiparametric regression models with nonparametric variance function. The validity of the proposed test is illustrated by two simulated examples and a real data example.展开更多
In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location,a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in th...In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location,a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in this paper.Firstly,the 3-terminal synchronous fundamental positive sequence voltage and current phasors are extracted and substituted into the fault branch distance function to realize the selection of fault branch when the fault occurs;Secondly,use the condition of the fundamental positive sequence voltage phasor at the fault point is equal to calculate all roots(including real root and virtual roots);Finally,the phase-angle jump check function is used for checking calculation,and then the only real root can be determined as the actual fault distance,thereby achieving the purpose of high-precision fault location.MATLAB simulation results show that the proposed new algorithm is feasible and effective with high fault location accuracy and good versatility.展开更多
目的探讨诊室血压与功能检查室血压的关系及二者诊断高血压的一致性。方法入选门诊疑似高血压患者388例,年龄15-89岁,平均(54.30±14.53)岁;其中男187例,平均(50.39±15.44)岁;女201例,平均(57.95±12.66)岁。采用汞...目的探讨诊室血压与功能检查室血压的关系及二者诊断高血压的一致性。方法入选门诊疑似高血压患者388例,年龄15-89岁,平均(54.30±14.53)岁;其中男187例,平均(50.39±15.44)岁;女201例,平均(57.95±12.66)岁。采用汞柱式标准袖带式血压计检测、记录所有患者的诊室血压并计数心率;采用欧姆龙动脉硬化检测仪(BP-203RPEⅢ)检测、记录四肢动脉血压和心率,并对上述数据进行统计学分析。结果 1总体上诊室血压及心率高于功能检查室血压及心率;诊室收缩压与功能检查室收缩压差值平均值为12.36 mm Hg;舒张压差值平均值为8.42 mm Hg;心率差值平均值为6.17次/min。2388例疑似高血压患者中,根据诊室血压有90.72%(352/388例)被诊断为高血压;根据功能检查室血压有53.09%(206/388例)被诊断为高血压;而且诊室高血压患者中只有56.82%(200/352例)的患者通过功能检查室血压诊断为高血压。结论 1诊室血压与功能检查室血压高血压诊断的一致性较差。2单纯根据诊室血压进行高血压的诊断会带来较大的误诊率和一定的漏诊率。展开更多
基金Supported by the Natural Science Foundation of Jiangsu Province (BK2008284)
文摘The assumption of homoscedasticity has received much attention in classical analysis of regression. Heteroscedasticity tests have been well studied in parametric and nonparametric regressions. The aim of this paper is to present a test of heteroscedasticity for nonlinear semiparametric regression models with nonparametric variance function. The validity of the proposed test is illustrated by two simulated examples and a real data example.
基金supported by National Nature Science Foundation of China(51507031).
文摘In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location,a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in this paper.Firstly,the 3-terminal synchronous fundamental positive sequence voltage and current phasors are extracted and substituted into the fault branch distance function to realize the selection of fault branch when the fault occurs;Secondly,use the condition of the fundamental positive sequence voltage phasor at the fault point is equal to calculate all roots(including real root and virtual roots);Finally,the phase-angle jump check function is used for checking calculation,and then the only real root can be determined as the actual fault distance,thereby achieving the purpose of high-precision fault location.MATLAB simulation results show that the proposed new algorithm is feasible and effective with high fault location accuracy and good versatility.
文摘目的探讨诊室血压与功能检查室血压的关系及二者诊断高血压的一致性。方法入选门诊疑似高血压患者388例,年龄15-89岁,平均(54.30±14.53)岁;其中男187例,平均(50.39±15.44)岁;女201例,平均(57.95±12.66)岁。采用汞柱式标准袖带式血压计检测、记录所有患者的诊室血压并计数心率;采用欧姆龙动脉硬化检测仪(BP-203RPEⅢ)检测、记录四肢动脉血压和心率,并对上述数据进行统计学分析。结果 1总体上诊室血压及心率高于功能检查室血压及心率;诊室收缩压与功能检查室收缩压差值平均值为12.36 mm Hg;舒张压差值平均值为8.42 mm Hg;心率差值平均值为6.17次/min。2388例疑似高血压患者中,根据诊室血压有90.72%(352/388例)被诊断为高血压;根据功能检查室血压有53.09%(206/388例)被诊断为高血压;而且诊室高血压患者中只有56.82%(200/352例)的患者通过功能检查室血压诊断为高血压。结论 1诊室血压与功能检查室血压高血压诊断的一致性较差。2单纯根据诊室血压进行高血压的诊断会带来较大的误诊率和一定的漏诊率。