( 2 ) the causation that the caustic phenomena of electromagnetic wave propagation in two - dimension concave reflectors occurs and the types of singularities in caustic fields are investigated, and the conclusion that there are two types of singularities ( fold and cusp ) in caustic fields in two - dimension concave reflectors is obtained ; by symplectic geometrical method, formulations of computing wave fields in and far away from caustic fields in two - dimension concave reflectors are deduced, and the results are plotted in pictures. ( 3 ) the cause of the caustic phenomena of electromagnetic wave propagation in three - dimension concave reflectors and the types of singularities in caustic fields is discussed, and the conclusion that there are three main types of singularities ( fold, cusp and swallowtail ) in caustic fields in three - dimension concave reflectors is obtained ; by symplectic geometrical method, the formulae of computing wave fields in and far away from caustic fields in three - dimension concave reflectors are deduced. particularly, the wave fields in ellipsoid concave reflector are computed, and the results displayed in special sections are given
論文主要包括三個方面: ( 1 )分析了凹面反射的焦散現象,給出了不同凹面反射的焦散圖; ( 2 )分析了二維凹面反射波動場焦散現象產生的原因及焦散區奇性的種類,得出了二維凹面反射波動場焦散區奇性主要有折疊( fold )和尖點( cusp )兩種的結論,利用辛幾何方法構造了圓
錐曲面反射波動場非焦散區和焦散區的通用計算公式,並給出了圓柱面、橢圓柱面及雙曲柱面反射的計算結果; ( 3 )分析了三維凹面反射波動場焦散現象產生的原因及焦散區奇性的種類,得出了三維凹面反射波動場焦散區奇性主要有折疊( fom 、尖點kusp和燕
尾k )三種的結論,提出了利用辛幾何方法計算三維凹面反射波動場非焦散區和焦散區的計算方法,並給出了三軸不等橢球體凹面反射波動場的計算結果剖面圖。
The structural vibration breakdown analysis research on the fighter - xx centerline drop tank ' s tail cone
升機身副油箱
尾錐振動故障分析研究
Jaw chuck flange 、 driveplate 、 face plate 、 steady rest ( less than 2000mm ) 、 follow rest ( less than 2000mm ) 、 130 spinde bore 、 electric turret 、 electric quill 、 taper turning attachment
四爪卡盤及法蘭、花盤、撥盤、中心架( 2米以下) 、跟刀架( 2米以下) 、 130孔徑主軸、電動刀架、電動
尾座、
錐度靠模尺。
A funnel - shaped or cone - shaped device towed behind an aircraft as a target
飛機拖靶拖在飛機
尾部用作靶子的漏斗形或
錐形裝置
Propeller hubs. rear cones
槳轂.
尾錐
Their round tapered tail is about 12 inches long
水獺的
尾巴呈圓
錐狀,長12英寸。
Shipbuilding. shaft lines. keys and keyways for tapers on propeller shafts. diameters 110 mm to 680 mm
造船工業.軸線.直徑為mm mm的螺旋
尾軸
錐形體的鍵接
Taper pins with external thread, unhardened
螺
尾錐銷
Taper pins with external thread
螺
尾錐銷
Pin with conical end
螺
尾錐銷
Morse taper gauges ; taper ring gauges for taper shanks with drift tang
莫氏
錐度量規.第2部分:帶扁
尾錐柄用
錐度環規
Metric taper gauges ; taper ring gauges for taper shanks with drift tang
公制
錐度量規.第2部分:帶扁
尾錐柄用
錐度環規
During past year, 28 times of measurements for two units of b plant of zhelin hydropower station were made, the states of pressure pulsation in the draft cone tube, head cover and spiral case of units were acquired under different water heads, and the influences of that on safety and stability of units operations were also acquired
摘要在長達一年多的時間里,對柘林水電廠b廠兩臺機組進行了28臺次試驗,全面掌握了機組各水頭下
尾水
錐管、頂蓋和渦殼中的壓力脈動情況,以及對機組安全穩定運行的影響。
Specifications for split taper pins for aeronautical purposes
航空用
錐形開
尾銷規范
Wedge for taper shank with tang. dimensions
扁
尾錐柄用楔.尺寸
Changing diameter bush with 7 : 24 taper mose taper with tang. dimensions
7 : 24圓錐帶扁尾莫氏圓錐中間套.尺寸