Purpose In the research of the microwave pulse compression,it was found that a new physical model has a high power gain for the rectangular TE_(1,0,20) resonant mode at 2.920 GHz in S-band than the traditional physica...Purpose In the research of the microwave pulse compression,it was found that a new physical model has a high power gain for the rectangular TE_(1,0,20) resonant mode at 2.920 GHz in S-band than the traditional physical model.In this report,the model structure,physical principle,simulation results,and theoretical analysis will be given in detail.Methods In the new physical model of microwave pulse compression system,(1)the technologies of the over-moded resonant cavity and over-sized output waveguide were used together first time for the rectangular TE_(1,0,20) resonant mode at 2.920 GHz in S-band,in order to improve the Q-value of the microwave resonant cavity and increase the power gain of the output pulse;(2)optimize the dimensions of the coupling window to get the maximum efficiency of the energy storage in the resonant cavity.Results From the latest research,it was shown that,in the optimal resonant state,(1)the power gain of the system can reach up to 276.97.Relative the traditional physical model,the power gain increased by 53.40%;(2)in the optimal resonant state,the energy storage efficiency of the over-moded system has also reached up to 88.91%.Relative to the traditional physical model,the efficiency increased by 23.33%;(3)another important result is that the power gain is very sensitive to the deviations of the resonant cavity length and output waveguide position from their optimal values.For example,the power gain will decrease by 61.45 or 67.17%,if the length deviation of the resonant cavity is−0.10 mm or+0.10 mm.It is very important to the theoretical and experimental studies.Conclusion It was shown that the new physical model of microwave pulse compression system has a higher power gain than the traditional physical model,by using the over-moded technology to the resonant cavity and output waveguide.Because of the universality of this high-gain over-moded physical model,the high-gain over-moded technology can be applied directly to X,Ku,and Ka bands.展开更多
目的探讨采用持续灌流耳内镜手术模式(CIM-EES)一期鼓室成形术治疗Ⅲ、Ⅳ型鼓室硬化症的临床疗效。方法2019.3-2020.9对17例(21耳)Ⅲ、Ⅳ型鼓室硬化症患者,在持续灌流模式耳内镜下采用外嵌法,一期行Ⅱ型鼓室成形术,观察分析手术时间,鼓...目的探讨采用持续灌流耳内镜手术模式(CIM-EES)一期鼓室成形术治疗Ⅲ、Ⅳ型鼓室硬化症的临床疗效。方法2019.3-2020.9对17例(21耳)Ⅲ、Ⅳ型鼓室硬化症患者,在持续灌流模式耳内镜下采用外嵌法,一期行Ⅱ型鼓室成形术,观察分析手术时间,鼓膜愈合成功率,并比较术前及术后6个月平均气、骨导听阈(PTA)及气骨导差(A-B gap)。结果17例患者(21耳)术后鼓膜均一期完全愈合。手术时间平均为60.6±7.0min,术前平均气导听阈54.70±10.38 dB HL,术后6个月平均气导听阈35.24±11.66 dB HL,差异具有统计学意义(P<0.001)。术前及术后6个月平均气骨导差分别为34.93±9.30 dBHL和15.65±7.07 dB,差异具有统计学意义(P<0.001)。术前、术后骨导平均听阈差异无统计学意义(P>0.05),术后无患者出现皮瓣缺血坏死及外耳道狭窄。未出现感音神经性耳聋、面瘫及眩晕并发症。结论CIM-EES可以针对性解决传统耳内镜手术出血起雾污染镜头、热损伤等缺陷,提高手术流畅性及安全性。尤其对于Ⅲ、Ⅳ型鼓室硬化症手术,在持续灌流模式下可以抵近观察并精细清理镫骨周围硬化灶,有助于一期完成听骨链重建。近期疗效满意,远期疗效尚有待进一步随访观察。相对于内植法和外植法,外嵌法是一种新的技术改良,可以最大程度维持鼓室腔容积,减少粘连及听骨链移位的发生。展开更多
基金Supported by National Natural Science Foundation of China(Grand No.:10475081).
文摘Purpose In the research of the microwave pulse compression,it was found that a new physical model has a high power gain for the rectangular TE_(1,0,20) resonant mode at 2.920 GHz in S-band than the traditional physical model.In this report,the model structure,physical principle,simulation results,and theoretical analysis will be given in detail.Methods In the new physical model of microwave pulse compression system,(1)the technologies of the over-moded resonant cavity and over-sized output waveguide were used together first time for the rectangular TE_(1,0,20) resonant mode at 2.920 GHz in S-band,in order to improve the Q-value of the microwave resonant cavity and increase the power gain of the output pulse;(2)optimize the dimensions of the coupling window to get the maximum efficiency of the energy storage in the resonant cavity.Results From the latest research,it was shown that,in the optimal resonant state,(1)the power gain of the system can reach up to 276.97.Relative the traditional physical model,the power gain increased by 53.40%;(2)in the optimal resonant state,the energy storage efficiency of the over-moded system has also reached up to 88.91%.Relative to the traditional physical model,the efficiency increased by 23.33%;(3)another important result is that the power gain is very sensitive to the deviations of the resonant cavity length and output waveguide position from their optimal values.For example,the power gain will decrease by 61.45 or 67.17%,if the length deviation of the resonant cavity is−0.10 mm or+0.10 mm.It is very important to the theoretical and experimental studies.Conclusion It was shown that the new physical model of microwave pulse compression system has a higher power gain than the traditional physical model,by using the over-moded technology to the resonant cavity and output waveguide.Because of the universality of this high-gain over-moded physical model,the high-gain over-moded technology can be applied directly to X,Ku,and Ka bands.
文摘目的探讨采用持续灌流耳内镜手术模式(CIM-EES)一期鼓室成形术治疗Ⅲ、Ⅳ型鼓室硬化症的临床疗效。方法2019.3-2020.9对17例(21耳)Ⅲ、Ⅳ型鼓室硬化症患者,在持续灌流模式耳内镜下采用外嵌法,一期行Ⅱ型鼓室成形术,观察分析手术时间,鼓膜愈合成功率,并比较术前及术后6个月平均气、骨导听阈(PTA)及气骨导差(A-B gap)。结果17例患者(21耳)术后鼓膜均一期完全愈合。手术时间平均为60.6±7.0min,术前平均气导听阈54.70±10.38 dB HL,术后6个月平均气导听阈35.24±11.66 dB HL,差异具有统计学意义(P<0.001)。术前及术后6个月平均气骨导差分别为34.93±9.30 dBHL和15.65±7.07 dB,差异具有统计学意义(P<0.001)。术前、术后骨导平均听阈差异无统计学意义(P>0.05),术后无患者出现皮瓣缺血坏死及外耳道狭窄。未出现感音神经性耳聋、面瘫及眩晕并发症。结论CIM-EES可以针对性解决传统耳内镜手术出血起雾污染镜头、热损伤等缺陷,提高手术流畅性及安全性。尤其对于Ⅲ、Ⅳ型鼓室硬化症手术,在持续灌流模式下可以抵近观察并精细清理镫骨周围硬化灶,有助于一期完成听骨链重建。近期疗效满意,远期疗效尚有待进一步随访观察。相对于内植法和外植法,外嵌法是一种新的技术改良,可以最大程度维持鼓室腔容积,减少粘连及听骨链移位的发生。
