为更好地满足大型邮轮安全返港的相关要求,基于《国际海上人命安全公约》(International Convention for Safety of Life at Sea,SOLAS)和MSC.1/Circ.1369通函,结合大型邮轮设计的实际情况,针对系统评估的关键问题,提出面向邮轮设计的...为更好地满足大型邮轮安全返港的相关要求,基于《国际海上人命安全公约》(International Convention for Safety of Life at Sea,SOLAS)和MSC.1/Circ.1369通函,结合大型邮轮设计的实际情况,针对系统评估的关键问题,提出面向邮轮设计的安全返港相关理念。研究成果可为大型邮轮安全返港评估提供一定参考。展开更多
最新SOLAS公约(International Convention for safety of Life at Sea)要求2010年以后建造的船长超过120 m或具有3个或3个以上主竖区的邮轮需满足安全返港和有序撤离要求,对满足条件的大型邮轮的照明系统的配置及布置有重大影响。为掌...最新SOLAS公约(International Convention for safety of Life at Sea)要求2010年以后建造的船长超过120 m或具有3个或3个以上主竖区的邮轮需满足安全返港和有序撤离要求,对满足条件的大型邮轮的照明系统的配置及布置有重大影响。为掌握新规范衍生出的安全返港、有序撤离和安全区域等方面的新要求对照明系统的影响,从安全返港配置对照明系统的影响、安全区域划分对照明系统的影响和有序撤离对照明系统的影响等3个方面介绍新规范下邮轮照明系统的设计原则,明确照明系统的上级供电方式和电缆选用情况等,使大型邮轮照明系统的设计和布置满足邮轮在执行安全返港或有序撤离任务时对照度的要求,为后续大型及超大型邮轮的设计提供参考。展开更多
A novel silicon carbide(SiC) trench metal–oxide–semiconductor field-effect transistor(MOSFET) with a dual shield gate(DSG) and optimized junction field-effect transistor(JFET) layer(ODSG-TMOS) is proposed. The combi...A novel silicon carbide(SiC) trench metal–oxide–semiconductor field-effect transistor(MOSFET) with a dual shield gate(DSG) and optimized junction field-effect transistor(JFET) layer(ODSG-TMOS) is proposed. The combination of the DSG and optimized JFET layer not only significantly improves the device’s dynamic performance but also greatly enhances the safe operating area(SOA). Numerical analysis is carried out with Silvaco TCAD to study the performance of the proposed structure. Simulation results show that comparing with the conventional asymmetric trench MOSFET(Con-ATMOS), the specific on-resistance(Ron,sp) is significantly reduced at almost the same avalanche breakdown voltage(BVav). Moreover, the DSG structure brings about much smaller reverse transfer capacitance(Crss) and input capacitance(Ciss), which helps to reduce the gate–drain charge(Qgd) and gate charge(Qg). Therefore, the high frequency figure of merit(HFFOM) of Ron,sp·Qgdand Ron,sp· Qgfor the proposed ODSG-TMOS are improved by 83.5% and 76.4%, respectively.The switching power loss of the proposed ODSG-TMOS is 77.0% lower than that of the Con-ATMOS. In addition, the SOA of the proposed device is also enhanced. The saturation drain current(Id,sat) at a gate voltage(Vgs) of 15 V for the ODSGTMOS is reduced by 17.2% owing to the JFET effect provided by the lower shield gate(SG) at a large drain voltage. With the reduced Id,sat, the short-circuit withstand time is improved by 87.5% compared with the Con-ATMOS. The large-current turn-off capability is also improved, which is important for the widely used inductive load applications.展开更多
An analytical breakdown model under on state condition for high voltage RESURF LDMOS is proposed.The model considers the drift velocity saturation of carriers and influence of parasitic bipolar transistor.As a result...An analytical breakdown model under on state condition for high voltage RESURF LDMOS is proposed.The model considers the drift velocity saturation of carriers and influence of parasitic bipolar transistor.As a result,electric field profile of n drift in LDMOS at on state is obtained.Based on this model,the electric SOA of LDMOS can be determined.The analytical results partially fit to our numerical (by MEDICI) and experiment results.This model is an aid to understand the device physics during on state accurately and it also directs high voltage LDMOS design.展开更多
The study was to investigate thrombolysis in vitro with ultrasound, and to discuss effects of thrombolysis with ultrasound on the structure of erythrocyte and its safety threshold under different ultrasound intensity ...The study was to investigate thrombolysis in vitro with ultrasound, and to discuss effects of thrombolysis with ultrasound on the structure of erythrocyte and its safety threshold under different ultrasound intensity and exposure time. The structure of erythrocyte in thrombus was evaluated under light microscope. The relationship between the structure of erythrocyte in thrombus and ultrasound intensity and exposure time was obtained. The results showed that ultrasound eliminated the thrombus. According to the change of the structure of erythrocyte in thrombus and ultrasound intensity and exposure time, the effects of thrombolysis with ultrasound could be divided into three kinds of areas: the A, B, C area. The area A was the safe area, the area B was the relatively safe area, and the area C was the irreversible damage area. The study suggested that ultrasound intensity and exposure time had significant impact on the structure of erythrocyte. Stronger ultrasound intensity or longer exposure time could cause erythrocytes irreversible damage. It could accelerate thrombolysis and shorten the exposure time that the ultrasound intensity was little bit increased. The study of effects of thrombolysis with ultrasound on the structure of erythrocyte and its safety threshold were important for practical applications.展开更多
文摘为更好地满足大型邮轮安全返港的相关要求,基于《国际海上人命安全公约》(International Convention for Safety of Life at Sea,SOLAS)和MSC.1/Circ.1369通函,结合大型邮轮设计的实际情况,针对系统评估的关键问题,提出面向邮轮设计的安全返港相关理念。研究成果可为大型邮轮安全返港评估提供一定参考。
文摘最新SOLAS公约(International Convention for safety of Life at Sea)要求2010年以后建造的船长超过120 m或具有3个或3个以上主竖区的邮轮需满足安全返港和有序撤离要求,对满足条件的大型邮轮的照明系统的配置及布置有重大影响。为掌握新规范衍生出的安全返港、有序撤离和安全区域等方面的新要求对照明系统的影响,从安全返港配置对照明系统的影响、安全区域划分对照明系统的影响和有序撤离对照明系统的影响等3个方面介绍新规范下邮轮照明系统的设计原则,明确照明系统的上级供电方式和电缆选用情况等,使大型邮轮照明系统的设计和布置满足邮轮在执行安全返港或有序撤离任务时对照度的要求,为后续大型及超大型邮轮的设计提供参考。
基金Project supported by the China Postdoctoral Science Foundation (Grant No. 2020M682607)。
文摘A novel silicon carbide(SiC) trench metal–oxide–semiconductor field-effect transistor(MOSFET) with a dual shield gate(DSG) and optimized junction field-effect transistor(JFET) layer(ODSG-TMOS) is proposed. The combination of the DSG and optimized JFET layer not only significantly improves the device’s dynamic performance but also greatly enhances the safe operating area(SOA). Numerical analysis is carried out with Silvaco TCAD to study the performance of the proposed structure. Simulation results show that comparing with the conventional asymmetric trench MOSFET(Con-ATMOS), the specific on-resistance(Ron,sp) is significantly reduced at almost the same avalanche breakdown voltage(BVav). Moreover, the DSG structure brings about much smaller reverse transfer capacitance(Crss) and input capacitance(Ciss), which helps to reduce the gate–drain charge(Qgd) and gate charge(Qg). Therefore, the high frequency figure of merit(HFFOM) of Ron,sp·Qgdand Ron,sp· Qgfor the proposed ODSG-TMOS are improved by 83.5% and 76.4%, respectively.The switching power loss of the proposed ODSG-TMOS is 77.0% lower than that of the Con-ATMOS. In addition, the SOA of the proposed device is also enhanced. The saturation drain current(Id,sat) at a gate voltage(Vgs) of 15 V for the ODSGTMOS is reduced by 17.2% owing to the JFET effect provided by the lower shield gate(SG) at a large drain voltage. With the reduced Id,sat, the short-circuit withstand time is improved by 87.5% compared with the Con-ATMOS. The large-current turn-off capability is also improved, which is important for the widely used inductive load applications.
文摘An analytical breakdown model under on state condition for high voltage RESURF LDMOS is proposed.The model considers the drift velocity saturation of carriers and influence of parasitic bipolar transistor.As a result,electric field profile of n drift in LDMOS at on state is obtained.Based on this model,the electric SOA of LDMOS can be determined.The analytical results partially fit to our numerical (by MEDICI) and experiment results.This model is an aid to understand the device physics during on state accurately and it also directs high voltage LDMOS design.
基金The work was supported by the National Natural Science Foundation of China ( No.10074043) and the Natural ScienceFoundation of Shaanxi Province (No.2003A05) .
文摘The study was to investigate thrombolysis in vitro with ultrasound, and to discuss effects of thrombolysis with ultrasound on the structure of erythrocyte and its safety threshold under different ultrasound intensity and exposure time. The structure of erythrocyte in thrombus was evaluated under light microscope. The relationship between the structure of erythrocyte in thrombus and ultrasound intensity and exposure time was obtained. The results showed that ultrasound eliminated the thrombus. According to the change of the structure of erythrocyte in thrombus and ultrasound intensity and exposure time, the effects of thrombolysis with ultrasound could be divided into three kinds of areas: the A, B, C area. The area A was the safe area, the area B was the relatively safe area, and the area C was the irreversible damage area. The study suggested that ultrasound intensity and exposure time had significant impact on the structure of erythrocyte. Stronger ultrasound intensity or longer exposure time could cause erythrocytes irreversible damage. It could accelerate thrombolysis and shorten the exposure time that the ultrasound intensity was little bit increased. The study of effects of thrombolysis with ultrasound on the structure of erythrocyte and its safety threshold were important for practical applications.
