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initial velocity 【物理學】初速(度)。

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The authors established an initial velocity model based on the first break time of the actual data , then realized the forward calculation with the improved shortest path ray tracing algorithm , and applied the improved constrained damped simultaneous iterative reconstruction technique ( cdsirt ) to solve large - scale and sparse equations for inversing the near - surface velocity field 根據實際地震數據的初至波時間建立初始速度模型;采用改進的最短路徑射線追蹤算法進行正演;利用改進的約束帶阻尼聯合迭代重建技術( cdsirt )求解大型、稀疏的方程組來反演近地表的速度場。

Spectral method and spectral element method are both used in the present dns . the flow is developed from an initial velocity field whose mean and root mean square values are fitted to the experimental data . the reynolds number of the flow is 2250 based on the mean velocity and the radius of the pipe 本文在空間離散上采用譜方法和譜元法的結合,通過在圓管層流速度剖面上疊加隨機擾動作為初始場的方法,計算了管長為,平均雷諾數為2250的光滑圓管內的湍流流動,建立了圓管內較低雷諾數下速度場和壓力場的數據庫。

Firing error caused by using the nato meteorological layer - weight , by using the approximate meteorological layer - weight and by using the exact meteorological layer - weight under different initial velocity and different ballistic coefficient is analyzed . firing error caused by air - layer numbers of trajectory are set forth 討論了在不同初速和彈道系數下用北約層權、近似層權和準確層權計算的射擊諸元精度,闡明了利用準確層權及近似層權時彈道分層數對射擊精度的影響、不同初速與彈道系數下分層數與精度的關系。

At the same time , the thickness of target should also be in accord with the impact velocity . experiments of quasi - isentropic loading to 93 w alloys by 93w - ofc - tc4 - a1 - mbz system flier - plate with graded wave impedance were performed on light gas guns . the corrected visar - measured wave profiles were profiles with an initial velocity jump followed by a stepwise - rising front to the peak velocity amplitude , indicating that quasi - isentropic compression energy waves had been successfully generated 在輕氣炮上利用研制的93w - ofc一tc4 . ai一mbz系波阻抗梯度飛片實現了對93w合金(靶材料)的準等嫡壓縮,經修正后的測試波形都是由一個較弱的初始速度跳躍和一段呈階梯狀緩慢上升的波陣面前沿所組成的準等嫡壓縮波。

At the same time , the mathematical models of the electric field and the flow field distribution were established from the theory of electrostatic enhancement of heat transfer . employed finite differential method and over - relaxation iteration method , according to certain boundary conditions in the wire - plate electrode space , the electric field and the flow field in the wire - plate space were numerically simulated under different initial velocities of r11 stream and different magnitudes of applied voltage . the calculation results agreed with theoretical analysis satisfactorily 同時從靜電強化換熱理論出發,建立了表征線板電極間的電場和流場分布的數學模型,并根據線-板電極間的邊界條件,利用有限差分法和超松弛迭代法,分別就不同氣流初速度和不同外施電壓的情況下,對線-板空間的電場和流場進行了數值模擬,計算結果與理論分析基本一致。

The results showed that quasi - isentropic compression energy waves were produced after the impact , whose initial velocity jump , peak velocity and front ' s rise - time were all different from the general shock loading wave profiles . furthermore , the higher the impact velocity , the smaller the extended wave ' s front while the higher the peak velocity 結果表明,梯度飛片擊靶后產生的是波陣面明顯被展寬的準等熵壓縮波,準等熵壓縮波的初始速度跳躍、速度峰值和波陣面前沿的上升時間都呈現出不同于傳統沖擊波陡峭上升波形的特征。

As a part of the civil 863 plans , two multiple - contact models for two kinds of braking system are built in the paper , in which contact fields are described as coons surfaces , initial velocity is programmed in fortran . the thermal - mechanical coupling braking processes are simulated for the first time by msc . marc , the general - used nonlinear fem software . time distributions of the velocity , the stress and the temperature of the components under various initial velocity and brake force are obtained , which offer theoretic gist to study the life of the wheel , the disc and so on 作為國家行業863重大課題《鐵路機車車輛虛擬樣機系統》的一部分,本文在研究接觸問題和熱?機耦合問題數值方法的基礎上,采用國際上通用的非線性有限元分析軟件msc . marc建立了踏面制動和盤形制動主要部件的多體接觸計算模型,其中用解析方法描述,即用nurb曲線、高斯曲面來描述接觸區域,用fortran語言編寫定義初速度的用戶子程序,首次對兩種制動過程熱?機耦合進行了數值仿真,定量給出了主要制動部件在不同初速度、不同制動力下各個時刻的速度、應力和溫度的變化規律,為研究車輪、閘瓦以及制動盤壽命提供了理論依據。

The anti - lock braking processes based on logic threshold control are simulated in the environment of matlab / simulink software . the influences on logic threshold control abs by the factors such as road condition , initial velocity , the changing rate of braking torque , delay time , inertia and load are discussed at the same time 運用matlab simulink軟件,對基于邏輯門限控制方法的防抱制動過程進行了計算機模擬,并分析了路面、初速、制動力矩變化率、延遲時間、轉動慣量及載荷等因素對邏輯門限控制abs的影響。

Geological model is set up by using seismic data interpretation result to perform ray - trace forward modeling analysis , and to guide the establishment of initial velocity model of pre - stack depth migration , thus reaching the purpose of precise image of complex structure under complex surface 利用已有地震資料解釋成果,建立地質模型進行射線追蹤正演模擬分析,從而指導疊前深度偏移初始速度模型的建立,達到了復雜地表下復雜構造精確成像的目的。

The results showed that quasi - isentropic compression energy waves were produced after the impact with mg - face of the flier - plate , whose initial velocity jump , peak velocity and front ' s rise - time were all different from the general shock loading wave profiles 結果表明,梯度飛片正向擊靶后產生的是波陣面明顯被展寬的準等熵壓縮波,準等熵壓縮波的初始速度跳躍、速度峰值和波陣面前沿的上升時間都呈現出不同于傳統沖擊波陡峭上升波形的特征。

The corrected visar - measured wave profiles on the interface between target and window were profiles with an initial velocity jump followed by a stepwise - rising front to the peak velocity amplitude , indicating that quasi - isentropic compression energy waves had been successfully generated 對visar測試到的波形進行合理的修正后,得到的界面速度波形都是由一個較弱的初始速度跳躍和一段緩慢上升的波陣面前沿所組成的準等熵壓縮波。

The paper simulate the transient thermal response of projectile wing according to the simulation software , and discuss the ablation characteristic when the projectile wing is in different initial velocity , in different wing shape , in different atmosphere condition and in different material condition 本文通過仿真軟件模擬了彈翼的瞬時燒蝕外形,并詳細討論了不同初速、不同翼形、不同氣象條件及不同材料條件下的燒蝕特性。

In this paper , we describe the research and realization of the high - speed data acquisition system applied in initial velocity radar . the sampling rate can reach 40msps , and the resolution is 12 bits . the acquisition speed that the system provides can be altered 本文介紹了基于初速雷達的高速數據采集系統的研制和實現方法,該系統提供了最高40mhz的采樣速率、 12位采樣精度的數據采集通道,且采樣頻率可調。

The initial velocity jump and velocity peak of the quasi - isentropic waves are greatly concerned with shock wave impedance of the targets . changing the impact conditions , there are evident differences among the quasi - isentropic energy 隨著擊靶速度的提高,準等熵壓縮波的波陣面前沿的上升時間逐漸減小,而對應的速度峰值和初始跳躍則不斷增加。

The origins of dispersion error are analyzed ; effects of initial velocity dispersion , ballistic coefficient dispersion , drift coefficient dispersion , range wind & cross wind dispersion on the ballistic dispersion are discussed 分析了散布誤差的起源,討論了初速散布、射角散布、彈道系數散布、偏流散布、縱橫風散布對密集度的影響。

Visar - measured wave profiles on the free surface of target were profiles with an initial velocity jump followed by a smoothly - rising front to the peak velocity amplitude , showing that quasi - isentropic loading has been successfully generated Visar測試得到的是波陣面上升前沿被明顯展寬的準等熵壓縮波,最高的擊靶壓力達到了260gpa 。

The physical phenomena of underwater explosion are analyzed , and the initial velocity equations and dynamics equations of water particles , which compose the water columns , are set up 從分析水中爆炸的物理現象入手,建立了構成水柱的各水粒子的初始速度計算模型,結合水粒子的受力情況,給出了水粒子的運動方程。

On the basis of duality multinomial fit , the fast algorithm of revising shooting error which is conduced by the changing of cannon muzzle initial velocity is set up 論述了二元射表多項式擬合,在此基礎上作者提出了可行的炮口初速修正快速實時算法,很好的修正了彈丸初速改變量引起的射擊誤差。

The utilizing firing result is to correct the initial condition when resolving ballistic equation set by using correction of initial velocity and ballistic coefficient converted from the firing result 采用將射擊成果轉換為初速和彈道系數修正量,修正解彈道方程初始條件的方式利用射擊成果。