利用全身定位体架及基部剂量计划补偿(BDPC)技术研究一种全脑全脊髓放疗方法。对本院11例中枢神经系统恶性肿瘤患者进行研究。采用全身定位体架配合头颈肩模和体膜进行患者体位固定并利用基部剂量计划补偿(Base Dose Plan Compensation,...利用全身定位体架及基部剂量计划补偿(BDPC)技术研究一种全脑全脊髓放疗方法。对本院11例中枢神经系统恶性肿瘤患者进行研究。采用全身定位体架配合头颈肩模和体膜进行患者体位固定并利用基部剂量计划补偿(Base Dose Plan Compensation,BDPC)模块进行调强优化。评价靶区适形度指数(CI)、均匀性指数(HI)和危及器官(OAR)受量及射野衔接处剂量。此种方法提高了靶区适形度和均匀性,简化了计划设计过程,提高了摆位精度并保证了重复性。射野衔接处未出现剂量冷热点,与计算值基本一致。通过本研究证明全身定位技术联合BDPC优化方法在全脑全脊髓放疗中能满足临床剂量学要求,操作简便,提高计划设计效率。展开更多
为满足内燃-直线发电集成动力系统(Internal Combustion-Linear Generator Integrated Power System,ICLGIPS)能量的双向高效流动要求,提出了一种储能系统,采用超级电容器组串并联切换技术和优化设计的双向DC-DC功率变换器(Bi-direction...为满足内燃-直线发电集成动力系统(Internal Combustion-Linear Generator Integrated Power System,ICLGIPS)能量的双向高效流动要求,提出了一种储能系统,采用超级电容器组串并联切换技术和优化设计的双向DC-DC功率变换器(Bi-directional DC-DC Power Converter,BDPC)相结合,实现了低电压值等级电源供电的可变电压系统的设计理念,电源电压和系统电压可以独立变化,使得系统电压可随不同动力装置的需要而改变。新系统可实现双向升、降压变换四种模式的能量控制策略,大大增加了电机的调速范围和可实现能量回馈的速度范围。利用超级电容器组串并联切换技术,实现了电压大范围变化条件下的BDPC的电压比被控制在理想范围内,提高了功率变换和传输的效率。仿真结果和部分实验结果验证了新系统设计的正确性和控制策略的有效性,能量流效率较好地满足了系统的要求。展开更多
When the authors research on the fact that some SVC （static var compensator） substations connected at some buses in power system, they realized that some main functions ensured to operate well. Those are： compensat...When the authors research on the fact that some SVC （static var compensator） substations connected at some buses in power system, they realized that some main functions ensured to operate well. Those are： compensate reactive power following value U＊ according to the requirements of the Vietnamese power system dispath center, flit harmonic by passive filter... However, it still has some disadvantages of this substation that need to be overcome： use large number of main devices, generate harmonics by itself, cause a lot of active power losses. Thus, the authors have an idea to solve these problems by applying a bidirectional power converter with having difference circuit structure and PWM （pulse width modulation） controller with SVM （space vector modulation） pulse generated section, so compensative current which is created by inductance element can be reserved, adjust continuos and always has full sinusoidal form, not generating harmonic. The benefit of this new solution is to eliminate the three above fundamental disadvantages. This new model is built based on authors＇ research about BESS （battery energy storage system）. The research results have been verified by simulations in Matlab/Simulink software.展开更多
文摘利用全身定位体架及基部剂量计划补偿(BDPC)技术研究一种全脑全脊髓放疗方法。对本院11例中枢神经系统恶性肿瘤患者进行研究。采用全身定位体架配合头颈肩模和体膜进行患者体位固定并利用基部剂量计划补偿(Base Dose Plan Compensation,BDPC)模块进行调强优化。评价靶区适形度指数(CI)、均匀性指数(HI)和危及器官(OAR)受量及射野衔接处剂量。此种方法提高了靶区适形度和均匀性,简化了计划设计过程,提高了摆位精度并保证了重复性。射野衔接处未出现剂量冷热点,与计算值基本一致。通过本研究证明全身定位技术联合BDPC优化方法在全脑全脊髓放疗中能满足临床剂量学要求,操作简便,提高计划设计效率。
文摘为满足内燃-直线发电集成动力系统(Internal Combustion-Linear Generator Integrated Power System,ICLGIPS)能量的双向高效流动要求,提出了一种储能系统,采用超级电容器组串并联切换技术和优化设计的双向DC-DC功率变换器(Bi-directional DC-DC Power Converter,BDPC)相结合,实现了低电压值等级电源供电的可变电压系统的设计理念,电源电压和系统电压可以独立变化,使得系统电压可随不同动力装置的需要而改变。新系统可实现双向升、降压变换四种模式的能量控制策略,大大增加了电机的调速范围和可实现能量回馈的速度范围。利用超级电容器组串并联切换技术,实现了电压大范围变化条件下的BDPC的电压比被控制在理想范围内,提高了功率变换和传输的效率。仿真结果和部分实验结果验证了新系统设计的正确性和控制策略的有效性,能量流效率较好地满足了系统的要求。
文摘When the authors research on the fact that some SVC （static var compensator） substations connected at some buses in power system, they realized that some main functions ensured to operate well. Those are： compensate reactive power following value U＊ according to the requirements of the Vietnamese power system dispath center, flit harmonic by passive filter... However, it still has some disadvantages of this substation that need to be overcome： use large number of main devices, generate harmonics by itself, cause a lot of active power losses. Thus, the authors have an idea to solve these problems by applying a bidirectional power converter with having difference circuit structure and PWM （pulse width modulation） controller with SVM （space vector modulation） pulse generated section, so compensative current which is created by inductance element can be reserved, adjust continuos and always has full sinusoidal form, not generating harmonic. The benefit of this new solution is to eliminate the three above fundamental disadvantages. This new model is built based on authors＇ research about BESS （battery energy storage system）. The research results have been verified by simulations in Matlab/Simulink software.
