The paper analyzes the motion of electron in plasma antenna and the distribution of electromagnetic field power around the plasma antenna, and proposes a self-consistent model according to the structure of cylindrical...The paper analyzes the motion of electron in plasma antenna and the distribution of electromagnetic field power around the plasma antenna, and proposes a self-consistent model according to the structure of cylindrical monopole plasma antenna excited by surface wave;calculation of the model is based on Maxwell-Boltzmann equation and gas molecular dynamics theory. The calculation results show that this method can reflect the relationships between the external excitation power, gas pressure, discharge current and the characteristic of plasma. It is an accurate method to predicate and calculate the parameters of plasma antenna.展开更多
Objective:This study was aimed at investigating the effects of preoperative treatment with a loading dose of statins combined with a PCSK9 inhibitor on coronary blood perfusion and short-term cardiovascular adverse ev...Objective:This study was aimed at investigating the effects of preoperative treatment with a loading dose of statins combined with a PCSK9 inhibitor on coronary blood perfusion and short-term cardiovascular adverse events in patients with ST-segment elevation myocardial infarction(STEMI).Method:Sixty-five patients with STEMI who had visited the Shanxi Cardiovascular Disease Hospital between May 2018 and May 2021 were enrolled in the study.The enrolled patients had no history of oral statins or antiplatelet therapy.The patients were divided into a combined treatment group(loading dose of statins combined with PCSK9 inhibitors,35 patients)and a routine treatment group(loading dose of statins only,30 patients).The primary endpoints were thrombolysis in myocardial infarction(TIMI)blood flow grading,corrected TIMI frame count(CTFC),and TIMI myocardial perfusion grading(TMPG),immediately after and 30 days after the operation.The secondary endpoint was a composite endpoint of cardiovascular death,nonfatal myocardial infarction,and target vessel revascularization 30 days after the operation.Results:The combined treatment group had significantly lower CTFC(14.09±8.42 vs 26±12.42,P=0.04)and better TMPG(2.74±0.61 vs 2.5±0.73,P=0.04)than the routine treatment group immediately after the operation.Similarly,the combined treatment group had a significantly lower CTFC(16.29±7.39 vs 26.23±11.53,P=0.04)and significantly better TMPG(2.94±0.24 vs 2.76±0.43,P=0.01)than the routine treatment group 1 month after the operation.Conclusion:Preoperative treatment with a loading dose of high-intensity statins combined with PCSK9 inhibitors increased coronary blood flow and myocardial perfusion after emergency thrombus aspiration in patients with STEMI.However,the treatment did not significantly decrease the incidence of cardiovascular death,nonfatal myocardial infarction,or target vessel revascularization.展开更多
Plasma’s conductive and dielectric properties have been well known for decades. Plasma antenna is a general terms representing using plasma as a conductive medium to transmit or reflect signals. It has unique propert...Plasma’s conductive and dielectric properties have been well known for decades. Plasma antenna is a general terms representing using plasma as a conductive medium to transmit or reflect signals. It has unique properties like low RCS (radar cross section), variable impedance and instant on-off capability. Previous plasma antenna uses RF power to generate the plasma column. We developed AC-biased (alternating current) plasma antenna, which has larger operation frequency scale and lower sustaining power. Signals propagated are coupled into the plasma antenna via capacitive coupling. Impedance of the plasma shifts slightly with the AC current. Radiation pattern of the plasma antenna is less uniform than metal antenna and its gain is related to AC power, from the measuring results of AC-biased plasma antenna we found its advantages compare to the plasma antenna excited by the surface wave.展开更多
The main advantage of tail-sitter unmanned aerial vehicle (UAV) are introduced. Three design solutions of rotor tail-sitter lift system of UAV have been presented and the respective control strategies and characterist...The main advantage of tail-sitter unmanned aerial vehicle (UAV) are introduced. Three design solutions of rotor tail-sitter lift system of UAV have been presented and the respective control strategies and characteristics of three solutions are also analyzed in the paper, through the related experiments the design of twin-rotor lift system is verified, and its feasibility is proved. The characteristics and the applying background of the twin-rotor tail-sitter UAV are described in detail. Some useful conclusions of the lift system for tail-sitter UAV are obtained.展开更多
In order to solve the difficulties of traditional simulation training method on unmanned reconnaissance aerial vehicle, such as the low environment fidelity, difficulty of modeling and long cycle of development, a sim...In order to solve the difficulties of traditional simulation training method on unmanned reconnaissance aerial vehicle, such as the low environment fidelity, difficulty of modeling and long cycle of development, a simulation training method based on Google Earth is put forward. The 6-DOF motion system of URAV is established through Matlab/Simulink. The visual simulation environment which is close to real scenes is formed though GE and software of SketchUp, and the visualization of flight data and elevation information of the region are also obtained through the software of GMS Aircraft Instrument and Measurement Studio. Experiments show that the method has satisfactory effects and its functions also can be strengthened, therefore it provides reference to related researchers.展开更多
文摘The paper analyzes the motion of electron in plasma antenna and the distribution of electromagnetic field power around the plasma antenna, and proposes a self-consistent model according to the structure of cylindrical monopole plasma antenna excited by surface wave;calculation of the model is based on Maxwell-Boltzmann equation and gas molecular dynamics theory. The calculation results show that this method can reflect the relationships between the external excitation power, gas pressure, discharge current and the characteristic of plasma. It is an accurate method to predicate and calculate the parameters of plasma antenna.
文摘Objective:This study was aimed at investigating the effects of preoperative treatment with a loading dose of statins combined with a PCSK9 inhibitor on coronary blood perfusion and short-term cardiovascular adverse events in patients with ST-segment elevation myocardial infarction(STEMI).Method:Sixty-five patients with STEMI who had visited the Shanxi Cardiovascular Disease Hospital between May 2018 and May 2021 were enrolled in the study.The enrolled patients had no history of oral statins or antiplatelet therapy.The patients were divided into a combined treatment group(loading dose of statins combined with PCSK9 inhibitors,35 patients)and a routine treatment group(loading dose of statins only,30 patients).The primary endpoints were thrombolysis in myocardial infarction(TIMI)blood flow grading,corrected TIMI frame count(CTFC),and TIMI myocardial perfusion grading(TMPG),immediately after and 30 days after the operation.The secondary endpoint was a composite endpoint of cardiovascular death,nonfatal myocardial infarction,and target vessel revascularization 30 days after the operation.Results:The combined treatment group had significantly lower CTFC(14.09±8.42 vs 26±12.42,P=0.04)and better TMPG(2.74±0.61 vs 2.5±0.73,P=0.04)than the routine treatment group immediately after the operation.Similarly,the combined treatment group had a significantly lower CTFC(16.29±7.39 vs 26.23±11.53,P=0.04)and significantly better TMPG(2.94±0.24 vs 2.76±0.43,P=0.01)than the routine treatment group 1 month after the operation.Conclusion:Preoperative treatment with a loading dose of high-intensity statins combined with PCSK9 inhibitors increased coronary blood flow and myocardial perfusion after emergency thrombus aspiration in patients with STEMI.However,the treatment did not significantly decrease the incidence of cardiovascular death,nonfatal myocardial infarction,or target vessel revascularization.
文摘Plasma’s conductive and dielectric properties have been well known for decades. Plasma antenna is a general terms representing using plasma as a conductive medium to transmit or reflect signals. It has unique properties like low RCS (radar cross section), variable impedance and instant on-off capability. Previous plasma antenna uses RF power to generate the plasma column. We developed AC-biased (alternating current) plasma antenna, which has larger operation frequency scale and lower sustaining power. Signals propagated are coupled into the plasma antenna via capacitive coupling. Impedance of the plasma shifts slightly with the AC current. Radiation pattern of the plasma antenna is less uniform than metal antenna and its gain is related to AC power, from the measuring results of AC-biased plasma antenna we found its advantages compare to the plasma antenna excited by the surface wave.
文摘The main advantage of tail-sitter unmanned aerial vehicle (UAV) are introduced. Three design solutions of rotor tail-sitter lift system of UAV have been presented and the respective control strategies and characteristics of three solutions are also analyzed in the paper, through the related experiments the design of twin-rotor lift system is verified, and its feasibility is proved. The characteristics and the applying background of the twin-rotor tail-sitter UAV are described in detail. Some useful conclusions of the lift system for tail-sitter UAV are obtained.
文摘In order to solve the difficulties of traditional simulation training method on unmanned reconnaissance aerial vehicle, such as the low environment fidelity, difficulty of modeling and long cycle of development, a simulation training method based on Google Earth is put forward. The 6-DOF motion system of URAV is established through Matlab/Simulink. The visual simulation environment which is close to real scenes is formed though GE and software of SketchUp, and the visualization of flight data and elevation information of the region are also obtained through the software of GMS Aircraft Instrument and Measurement Studio. Experiments show that the method has satisfactory effects and its functions also can be strengthened, therefore it provides reference to related researchers.
