This paper reviews the main benefits of Aronia melanocarpa Elliot for eye health,focusing on its antioxidant protection,prevention of visual deterioration,reduction of inflammation,improvement of blood circulation,pro...This paper reviews the main benefits of Aronia melanocarpa Elliot for eye health,focusing on its antioxidant protection,prevention of visual deterioration,reduction of inflammation,improvement of blood circulation,protection of the retina,and immunity enhancement.Based on the existing studies,the application of A.melanocarpa Elliot in the field of eye health is promising and deserves further research and promotion.展开更多
分析了风电机组异常数据分布特征,设计了MKIF(Mini-batch K means-isolation forest)算法,并基于MKIF算法构建了风电机组健康劣化监测预警模型。MKIF算法将小批量K均值聚类引入搜索树的划分过程中,使用轮廓系数监督树分裂节点的数量和...分析了风电机组异常数据分布特征,设计了MKIF(Mini-batch K means-isolation forest)算法,并基于MKIF算法构建了风电机组健康劣化监测预警模型。MKIF算法将小批量K均值聚类引入搜索树的划分过程中,使用轮廓系数监督树分裂节点的数量和位置。定义了MKIF异常得分以描述数据的孤立程度,进而有效识别和剔除异常数据并基于正常运行数据建立风电机组健康基准模型。使用健康基准模型和滑动窗口算法即可对监测数据劣化程度进行评估;当窗口内劣化数据比例超过设定阈值时,触发机组健康劣化预警。以某风电机组齿轮箱油温异常导致发电性能劣化为实例,验证了模型的有效性。展开更多
Surface roughness is a critical health parameter of a turbine blade due to its implications on blade surface heat transfer and structural integrity.This paper proposes a physics-based online framework for Gas Turbine ...Surface roughness is a critical health parameter of a turbine blade due to its implications on blade surface heat transfer and structural integrity.This paper proposes a physics-based online framework for Gas Turbine Engines(GTE),in order to assess the blade surface roughness in a highpressure turbine without engine shutdown.The framework consolidates Gas Path Analysis(GPA)based performance monitoring models and meanline turbomachinery analysis,using a novel GPAmeanline matching process.This extracts meaningful performance deviation trends from GPA,while addressing the uncertainties associated with the measurements and modelling.To relate efficiency loss to surface roughness severity,a meanline-based system-identification process has been developed to establish the meanline representation of the turbine stage,and to incorporate the empirical surface roughness loss correlations.The roughness loss correlations have been evaluated against recent transonic test data in the literature.A modification to the compressibility correction factor has been made according to the evaluation outcome,which improved loss predictions compared to the experimental measurements.The framework was tested on the three-year operational data of a cogeneration GTE,and the results verified the framework’s potential for online surface roughness monitoring.The predicted surface roughness showed agreement in both trend and the magnitude-level with the measurements reported in the literature.展开更多
目的探讨颅内动脉狭窄、血压变异性与急性缺血性脑卒中(AIS)患者神经功能及预后的关系。方法回顾性分析2018年1月—2021年1月收治的AIS 152例的临床资料。根据是否发生早期神经功能恶化(END)分为END组(n=45)和非END组(n=107)。根据卒中...目的探讨颅内动脉狭窄、血压变异性与急性缺血性脑卒中(AIS)患者神经功能及预后的关系。方法回顾性分析2018年1月—2021年1月收治的AIS 152例的临床资料。根据是否发生早期神经功能恶化(END)分为END组(n=45)和非END组(n=107)。根据卒中发病后90 d的预后情况分为预后良好组(n=60)和预后不良组(n=92)。评估颅内动脉狭窄程度,监测24 h动态血压,计算收缩压标准差(SSD)、舒张压标准差(DSD)。分析影响患者预后的危险因素。结果END组颅内动脉总狭窄率高于非END组,且END组颅内动脉狭窄程度更严重(P<0.05,P<0.01)。END组24 h SSD、24 h DSD、日间SSD、日间DSD、夜间SSD、夜间DSD均高于非END组(P<0.05,P<0.01)。END组杓型血压节律的比例低于非END组,而非杓型血压节律的比例高于非END组(P<0.05,P<0.01)。颅内动脉中、重度狭窄及入院时美国国立卫生研究院卒中量表评分>12分、24 h SSD>12 mmHg、发生END是导致AIS患者预后不良的危险因素,而杓型血压节律为保护性因素(P<0.05,P<0.01)。结论颅内动脉狭窄程度、血压变异性与AIS患者神经功能有关,且是预后的影响因素。展开更多
文摘This paper reviews the main benefits of Aronia melanocarpa Elliot for eye health,focusing on its antioxidant protection,prevention of visual deterioration,reduction of inflammation,improvement of blood circulation,protection of the retina,and immunity enhancement.Based on the existing studies,the application of A.melanocarpa Elliot in the field of eye health is promising and deserves further research and promotion.
文摘分析了风电机组异常数据分布特征,设计了MKIF(Mini-batch K means-isolation forest)算法,并基于MKIF算法构建了风电机组健康劣化监测预警模型。MKIF算法将小批量K均值聚类引入搜索树的划分过程中,使用轮廓系数监督树分裂节点的数量和位置。定义了MKIF异常得分以描述数据的孤立程度,进而有效识别和剔除异常数据并基于正常运行数据建立风电机组健康基准模型。使用健康基准模型和滑动窗口算法即可对监测数据劣化程度进行评估;当窗口内劣化数据比例超过设定阈值时,触发机组健康劣化预警。以某风电机组齿轮箱油温异常导致发电性能劣化为实例,验证了模型的有效性。
基金This project was supported by the Life Prediction Technologies Inc.(LPTi)and Natural Sciences and Engineering Research Council of Canada.
文摘Surface roughness is a critical health parameter of a turbine blade due to its implications on blade surface heat transfer and structural integrity.This paper proposes a physics-based online framework for Gas Turbine Engines(GTE),in order to assess the blade surface roughness in a highpressure turbine without engine shutdown.The framework consolidates Gas Path Analysis(GPA)based performance monitoring models and meanline turbomachinery analysis,using a novel GPAmeanline matching process.This extracts meaningful performance deviation trends from GPA,while addressing the uncertainties associated with the measurements and modelling.To relate efficiency loss to surface roughness severity,a meanline-based system-identification process has been developed to establish the meanline representation of the turbine stage,and to incorporate the empirical surface roughness loss correlations.The roughness loss correlations have been evaluated against recent transonic test data in the literature.A modification to the compressibility correction factor has been made according to the evaluation outcome,which improved loss predictions compared to the experimental measurements.The framework was tested on the three-year operational data of a cogeneration GTE,and the results verified the framework’s potential for online surface roughness monitoring.The predicted surface roughness showed agreement in both trend and the magnitude-level with the measurements reported in the literature.
文摘目的探讨颅内动脉狭窄、血压变异性与急性缺血性脑卒中(AIS)患者神经功能及预后的关系。方法回顾性分析2018年1月—2021年1月收治的AIS 152例的临床资料。根据是否发生早期神经功能恶化(END)分为END组(n=45)和非END组(n=107)。根据卒中发病后90 d的预后情况分为预后良好组(n=60)和预后不良组(n=92)。评估颅内动脉狭窄程度,监测24 h动态血压,计算收缩压标准差(SSD)、舒张压标准差(DSD)。分析影响患者预后的危险因素。结果END组颅内动脉总狭窄率高于非END组,且END组颅内动脉狭窄程度更严重(P<0.05,P<0.01)。END组24 h SSD、24 h DSD、日间SSD、日间DSD、夜间SSD、夜间DSD均高于非END组(P<0.05,P<0.01)。END组杓型血压节律的比例低于非END组,而非杓型血压节律的比例高于非END组(P<0.05,P<0.01)。颅内动脉中、重度狭窄及入院时美国国立卫生研究院卒中量表评分>12分、24 h SSD>12 mmHg、发生END是导致AIS患者预后不良的危险因素,而杓型血压节律为保护性因素(P<0.05,P<0.01)。结论颅内动脉狭窄程度、血压变异性与AIS患者神经功能有关,且是预后的影响因素。
