拋物點 的英文怎麼說
中文拼音 [pāowùdiǎn]
拋物點
英文
parabolic point-
A parabolic concave mirror can converge parallel light rays to its focus, and also collimate light rays that pass through its focus
拋物面凹鏡會把平行而來的光線聚集在一點焦點，亦會把源自焦點的光線平行向外反射。In this thesis, based on pershing ii surface to surface missile, a new kind of ballistic missile was designed with an additional rocket engine, which can be ignited twice. firstly, aerodynamic computational models of missile body and warhead which reentry with supersonic are built according to the task requirements ; secondly, the propulsion system model of missile is built whose first two stages are solid rocket engines and the third stage is liquid - solid combined rocket engine. the nozzle and the shape of the engine are designed to meet the needs of the populsion project ; thirdly, the trajectory model of the mass point is built and a wavy trajectory is designed & optimized ; finally, the ability of a missile ' s breaking through defence is analyzed
以美國潘興導彈為原型，增加可兩次點火的末級發動機，改裝成具有跳躍能力的地地彈道導彈；首先，根據任務需求，建立了導彈的氣動模型，並建立了彈頭再入時高超聲速氣動模型；其次，建立了導彈推進系統模型，前兩級採用了固體火箭發動機，第三級採用了固?液組合火箭發動機，並在總體方案要求下，對發動機噴管和外形進行了設計；第三部分，建立了導彈質點彈道模型，設計了一條跳躍式彈道，並對跳躍式彈道進行了優化設計；最後，對導彈進行了突防能力分析，從分析的結果可以看出，跳躍式彈道的突防能力比常規的拋物線彈道要強。To investigate the practicability of a solar - direct - pumped fiber laser by using a parabolic dish concentrator, the solar power absorbed by the fiber laser and its absorption efficiency were calculated with numerical method based on the characteristics of solar spectrum in outer space
摘要為了研究拋物面碟形聚光器實現太陽能直接抽運光纖激光器，根據空間太陽光譜分佈特點，採用數值方法，計算了用該聚光器聚集太陽能量抽運雙包層光纖激光器時光纖吸收的太陽能量及其吸收效率。It shows that the injection quantity and the difference of temperature distribute as a parabola which is at the same load, and the minimum of the parabola corresponds to the optimum quantity of injection ( g ). under the condition that the quantity of injected mass, the air speed and the heat quantity is respectively g, v and q, the research demonstrates that the pentium iv chip ' s temperature variation can be controlled under 40c and work normally when the wind speed overpass 1. 5m / s and the power dissipation of the chip is 60w. otherwise this paper calculates the flooding limit of thermosiphon with several different methods
對其充灌量、散熱量、電子元件（ cpu模擬晶元）表面與環境溫度之差及通風、流速的影響進行了系統的測試，發現充液量與溫差的關系在負荷不變時呈拋物線分佈，其極小值點對應的充液量是最佳充液量g 。在充液量為g時，對風速v 、散熱量q進行的研究表明，當風速超過1 . 5m / s后，奔騰晶元在60w發熱條件下晶元溫度小於40 ，能滿足長期正常工作。A reliability experiment of thermal aging was carried out for the two types of joints, scanning electron microscopy, energy dispersive x - ray spectrometer and micro x - ray diffractomer were adopted to investigate the interfacial evolution behavior of joints, and kinetics model of imc formation was established. the results show that imc growth follows the parabolic law as a function of aging time at certain aging temperature, imc growth is more sensitive to the aging temperature than the aging time, the activation energy of cu - al imc growth is 97. 1kj / mol and the major forming cu - al imc are cual2 and cu9al4, the activation energy of au - al imc growth is 40. 1kj / mol and the main au - al imc are au4al and au5al2, with au2al and aual at the interfacial periphery of joints, the rate of cu - al imc growth is about 1000 times slower than that of au - al imc, and kirkendall voids and cracks are easily appeared during thermal aging in gold ball bonds while voids and cracks are absent in copper ball bonds even after aging at 200 for 2900 hours and 250 for 169 hours
研究結果表明:金屬間化合物厚度與老化時間的關系符合拋物線法則，金屬間化合物的生長對老化溫度比老化時間更加敏感; cu - al金屬間化合物生長的激活能為97 . 1kj / mol ，老化后金屬間化合物呈層狀分佈，主要相為cual2和cu9al4 ; au - al金屬間化合物生長的激活能為40 . 1kj / mol ，主要相為au4al和au5al2 ，同時在界面周邊區域生成了au2al和aual ;老化過程中cu - al金屬間化合物生長速率比au - al金屬間化合物生長速率小103數量級;金絲球鍵合點200老化96小時出現了明顯的kirkendall空洞和裂紋，但銅絲球鍵合點200老化2900小時和250老化169小時都沒有形成空洞和裂紋。A normal transform is introduced, and there are enough much grids in the region between the critical layer and the wall, where the variation of the disturbance is the quickest. the finite - difference of governing equations with fourth - order accuracy in the normal direction is utilized in full regions including points close the wall, and is very important for accurately discreting equations. the combination of global and local methods is implemented, and a new iterative formula is derived
對于曲線坐標系下的拋物化穩定性方程，文中發展了求解的高效數值方法:引進法向變換，使得在臨界層與壁面之間的擾動量變化最快的區域有更多的法向網格點;導出包含邊界鄰域在內的完全四階精度的法向有限差分格式，這對方程精確離散至關重要;採用全局法和局部法相結合的方法及其新的迭代公式，大大加速收斂並得到更精確的特徵值。The implicit differencing scheme of nine points for solving the parabolic equations
解拋物型方程的九點隱格式The semi - explicit differencing scheme of seven points for solving the parabolic equations
解拋物型方程的七點半顯差分格式While carrying out the scheme, at first, the basic theory of antenna, array antenna and electromagnetic absorption, the performance parameter of antenna and parabolic antenna are deeply researched. in conformity, the characteristic and calculation of aperture field and near - to - far - field transformation for radiation pattern are detailed analyzed. second, the factors such as, the amount of the antenna elements, mutual coupling between each element, ground and the buildings on earth ' s surface, which affect the performance of array antennas ’ resultant field are stressed discussed
在系統實現過程中，課題首先從天線、陣列天線，以及電磁場計算方法的基本理論著手，分析了天線與拋物面天線的各項性能參數，以及天線的口面場和近-遠區輻射場的特點和計算;進而，更加深入的討論和研究影響天線陣列合成場強的各項因素，包括系統所使用的天線單元個數對陣列合成場的影響、天線單元之間由於互耦造成的影響、傳播過程中地面和/或地面建築物的影響等。This paper proposed a hexahedral deployable space antenna, which is composed of hexahedral modules
結構的具體設計和幾何關系計算是拋物面天線設計的一個重點和難點。The first part makes a detailed exposition on " problem - inquiry " model in the aspects of historical origins, connotation, theoretical basis, operation programme, evaluation system and implementation conditions etc. in accordance with the different characteristics and requests of theoretical, experimental, exercises lessons, the second part illustrates how carry out " problem - inquiry " model respectively using the motion of level projectile, determine acceleration of gravity with single pendulum, the motion question of pursuit and meeting as living examples
第二部分（第二章）針對理論課、實驗課、習題課等不同課型的具體特點及要求，分別以《平拋物體的運動》 、 《用單擺測定重力加速度》 、 《追及與相遇問題》為實例，論述了在理論課、實驗課、習題課教學中，如何實施「問題一探究」式教學模式。After the comparing the simulation results with the theoretic results under the three followed condition : a point light source on the parabola reflector focus, a point light on the ellipsoid reflector focus and a point light source before the parabola reflector focus, a conclusion is gotten that the two results are generally accordant, the accuracy of the simulation software reach the engineering requirements and the computational simulation software of photometric characteristics of headlamp of motor vehicles can guide the design of the headlamp reflectors
比較了點光源位於拋物面反射器和橢球面反射器焦點的情況和點光源偏離拋物面焦點的情況下照度的理論計算結果和採用本文的照度模擬計算結果，其模擬計算結果和理論計算結果基本相符，能滿足工程上的要求，說明模擬計算軟體對前照燈的反射鏡的設計具有很好的指導意義。Theoretical analysis and numerical experiments show that the improved nine - point scheme not only has completely overcome the second drawback mentioned above that the original nine - point scheme can not apply to the parabolic problem with diffusion coefficient drastically varying, but also has partly improved the applicability of the scheme when performed over irregular grids
（ 2 ）針對九點格式的上述缺點提出了改進方案。改進后的九點格式完全克服了原格式不適用於熱傳導系數劇烈變化的拋物問題的缺點，同時部分改善了該格式對不規則網格的適應性問題。The result shows that the sufficient and necessary condition of the quadratic rational b - spline curve ' s curvature monotony is similar to the quadratic rational bezier curves ", but its condition is some different from the quadratic rational bezier curves " curve ' s rendering algorithm is an important content in computer graphics, cad
曲線的生成演算法是計算機圖形學的重要內容。對於一些基本曲線，如直線，圓，橢圓等，都有快速生成演算法，如畫直線的bresenham演算法， dda演算法，畫圓的bresenham演算法，中點法，正負法， pitterway的橢圓及拋物線繪制演算法等等。The performance was much like all acrobatic displays ; but it must be confessed that the japanese are the first equilibrists in the world. one, with a fan and some bits of paper, performed the graceful trick of the butterflies and the flowers ; another traced in the air, with the odorous smoke of his pipe, a series of blue words, which composed a compliment to the audience ; while a third juggled with some lighted candles, which he extinguished successively as they passed his lips, and relit again without interrupting for an instant his juggling
有一個演員手裡拿著一把扇子和一些碎紙片，演出了非常美妙動人的「群蝶花間舞」另一個演員用他那從煙斗里噴出來的一縷芬芳的煙霧，在空中迅速地寫出許多青煙文字，這些字構成一句向觀眾致敬的頌詞又有一個耍拋物戲的演員，他一面把幾支點著的蠟燭輪流地從手裡拋起，一面把每一支從嘴前面經過的蠟燭吹熄，然後再陸續地把它們點著，同時卻一秒鐘也不中止他那神奇的拋擲動作。After the first stage burns out, it falls back to earth along a parabolic path, while the engines of the second stage fire to thrust the rocket into an earth orbit
當第一級燒毀后，沿拋物線的軌道落到地球，而第二級的發動機點火把火箭發射到地球軌道。The period of oscillation of qubit in a parabolic linear bound potential quantum dot
拋物線性限制勢量子點量子比特的振蕩周期A calculation method and calculation results that show that a new kind of shaped paraboloid antennas can produce a ringy radiation pattern is presented
摘要通過數值計算發現：將拋物線繞通過焦點的非拋物線對稱軸旋轉而形成的賦形拋物面天線可產生環狀的方向圖主瓣（此主瓣指的是主瓣最大值處） 。A plane curve formed by the locus of points equidistant from a fixed line and a fixed point not on the line
拋物線到一固定直線和不在直線上某一固定點等距的點的軌跡所形成的平面曲線Aimmed to retard the response of ballistic missile defence system, the wavy trajectory with three crests is designed in this thesis to replace traditional parabola one. this kind of trajectory make anti - defence system have lots of difficulties to detect and compute the track and destination of ballistic missiles before reentry. so, applying the wavy trajectory can greatly improve the anti - defence ability of ballistic missiles
從延緩導彈防禦系統的早期預警時間著手，將傳統彈道導彈的拋物線彈道中段設計成有多個波峰的跳躍式彈道，使得探測系統在導彈再入大氣層之前，很難準確探測和計算導彈的落點，使得防禦系統防不勝防，從而大大地提高了彈道導彈的突防能力。分享友人