为解决单绕组磁悬浮开关磁阻电机(single winding bearingless switched reluctance motor,SWBSRM)运行脉动以及转矩与悬浮力耦合问题,提出了二阶滑模(second order sliding mode,SOSM)—直接转矩与直接悬浮力控制(direct torque and di...为解决单绕组磁悬浮开关磁阻电机(single winding bearingless switched reluctance motor,SWBSRM)运行脉动以及转矩与悬浮力耦合问题,提出了二阶滑模(second order sliding mode,SOSM)—直接转矩与直接悬浮力控制(direct torque and direct suspension force control,DT/DSFC)策略。针对SWBSRM单绕组运行方式,采用五电平功率变换器,结合麦克斯韦应力和机电能量转换原理,推导出SWBSRM磁链、电压、转矩和悬浮力的直接数值解析模型,构建分电压输入模块,实现转矩与悬浮力解耦控制。为进一步提高系统鲁棒性与运行可靠性,消除稳态运行过程中转速脉动,结合超螺旋算法,设计出转矩子系统SOSM控制器,并构建样机控制系统。结果表明SOSM-DT/DSFC能有效消除控制系统的抖振,提高动态特性和鲁棒性,验证了控制策略的合理性与优越性。展开更多
目的:总结中山地区胸痛3D急救模式运行后胸痛患者的救治效果。方法:以2017年10月-2018年4月在胸痛中心收治的胸痛患者为研究组,以胸痛中心国际标准为参照,比较远程传输比例、首次医疗接触到首份心电图(ECG)时间、首份ECG完成至首份ECG...目的:总结中山地区胸痛3D急救模式运行后胸痛患者的救治效果。方法:以2017年10月-2018年4月在胸痛中心收治的胸痛患者为研究组,以胸痛中心国际标准为参照,比较远程传输比例、首次医疗接触到首份心电图(ECG)时间、首份ECG完成至首份ECG确诊时间(STEMI患者)、入门至球囊扩张时间、导管室激活时间、肌钙蛋白获得时间。结果:与胸痛中心国际标准相比,STEMI患者首份ECG完成至首份ECG确诊时间(8.88±14.10)min虽短,但无明显差异(P>0.05);远程传输比例(95.60±4.07)%、首次医疗接触到首份ECG时间(6.34±28.03)min、D to B时间(74.06±35.81)min、导管室激活时间(13.70±13.45)min、肌钙蛋白获得时间(15.61±2.35)min均明显缩短(P<0.05)。结论:中山地区胸痛3D急救模式的运行能快速、高效地解决胸痛患者容易延误的难题,特别为STEMI患者争取时间和提高救治效率。展开更多
Root-knot nematodes（RKNs,Meloidogyne spp.） are obligate biotrophic parasites that settle close to the vascular tissues in plant roots.The diseases resulting from RKN infections cause serious damage to agricultural p...Root-knot nematodes（RKNs,Meloidogyne spp.） are obligate biotrophic parasites that settle close to the vascular tissues in plant roots.The diseases resulting from RKN infections cause serious damage to agricultural production worldwide.In the present paper,the resistance of Chinese leek（Allium tuberosum Rottler ex Sprengel） against RKNs,its suppressive effect on nematode disease,its nematicidal activity and its component profile were studied to identify an efficient disease control method.In soil heavily infected by nematodes,Chinese leek showed strong resistance to RKNs.Additionally,the gall indexes of cucumber plants rotated with Chinese leek and of tomato plants intercropped with Chinese leek were reduced by 70.2 and 41.1%,respectively.In a pot experiment,the gall indexes of Chinese leek extract-treated tomato and cucumber plants were reduced by 88.9 and 75.9%,respectively.In an in vitro experiment,the mortality rate of a RKN（Meloidogyne incognita J2） treated with Chinese leek extract was significantly higher than that of the control.The gas chromatography-mass spectrometry（GC-MS） analysis revealed that glycosides,carboxylic acids,ketones and organic sulfides are the main components in the Chinese leek extract.This study revealed that Chinese leek possesses a high resistance to RKNs,has strong nematicidal activity against M.incognita and can significantly reduce the incidence of disease caused by nematodes.展开更多
文摘为解决单绕组磁悬浮开关磁阻电机(single winding bearingless switched reluctance motor,SWBSRM)运行脉动以及转矩与悬浮力耦合问题,提出了二阶滑模(second order sliding mode,SOSM)—直接转矩与直接悬浮力控制(direct torque and direct suspension force control,DT/DSFC)策略。针对SWBSRM单绕组运行方式,采用五电平功率变换器,结合麦克斯韦应力和机电能量转换原理,推导出SWBSRM磁链、电压、转矩和悬浮力的直接数值解析模型,构建分电压输入模块,实现转矩与悬浮力解耦控制。为进一步提高系统鲁棒性与运行可靠性,消除稳态运行过程中转速脉动,结合超螺旋算法,设计出转矩子系统SOSM控制器,并构建样机控制系统。结果表明SOSM-DT/DSFC能有效消除控制系统的抖振,提高动态特性和鲁棒性,验证了控制策略的合理性与优越性。
文摘目的:总结中山地区胸痛3D急救模式运行后胸痛患者的救治效果。方法:以2017年10月-2018年4月在胸痛中心收治的胸痛患者为研究组,以胸痛中心国际标准为参照,比较远程传输比例、首次医疗接触到首份心电图(ECG)时间、首份ECG完成至首份ECG确诊时间(STEMI患者)、入门至球囊扩张时间、导管室激活时间、肌钙蛋白获得时间。结果:与胸痛中心国际标准相比,STEMI患者首份ECG完成至首份ECG确诊时间(8.88±14.10)min虽短,但无明显差异(P>0.05);远程传输比例(95.60±4.07)%、首次医疗接触到首份ECG时间(6.34±28.03)min、D to B时间(74.06±35.81)min、导管室激活时间(13.70±13.45)min、肌钙蛋白获得时间(15.61±2.35)min均明显缩短(P<0.05)。结论:中山地区胸痛3D急救模式的运行能快速、高效地解决胸痛患者容易延误的难题,特别为STEMI患者争取时间和提高救治效率。
基金supported by the National Natural Science Foundation of China(31272151,31471864)the Agro-scientific Research in the Public Interest,China(201103018)the China Agriculture Research System(CARS-25)
文摘Root-knot nematodes（RKNs,Meloidogyne spp.） are obligate biotrophic parasites that settle close to the vascular tissues in plant roots.The diseases resulting from RKN infections cause serious damage to agricultural production worldwide.In the present paper,the resistance of Chinese leek（Allium tuberosum Rottler ex Sprengel） against RKNs,its suppressive effect on nematode disease,its nematicidal activity and its component profile were studied to identify an efficient disease control method.In soil heavily infected by nematodes,Chinese leek showed strong resistance to RKNs.Additionally,the gall indexes of cucumber plants rotated with Chinese leek and of tomato plants intercropped with Chinese leek were reduced by 70.2 and 41.1%,respectively.In a pot experiment,the gall indexes of Chinese leek extract-treated tomato and cucumber plants were reduced by 88.9 and 75.9%,respectively.In an in vitro experiment,the mortality rate of a RKN（Meloidogyne incognita J2） treated with Chinese leek extract was significantly higher than that of the control.The gas chromatography-mass spectrometry（GC-MS） analysis revealed that glycosides,carboxylic acids,ketones and organic sulfides are the main components in the Chinese leek extract.This study revealed that Chinese leek possesses a high resistance to RKNs,has strong nematicidal activity against M.incognita and can significantly reduce the incidence of disease caused by nematodes.
