脈動流速 的英文怎麼說
中文拼音 [màidòngliúsù]
脈動流速
英文
fluctuating velocity- 脈 : 脈名詞1. (動脈和靜脈的統稱) arteries and veins2. (脈搏的簡稱) pulse 3. (像血管的組織; 連貫成系統的東西) vein
- 流 : Ⅰ動1 (液體移動; 流動) flow 2 (移動不定) drift; move; wander 3 (流傳; 傳播) spread 4 (向壞...
- 速 : Ⅰ形容詞(迅速; 快) fast; rapid; quick; speedy Ⅱ名詞1 (速度) speed; velocity 2 (姓氏) a surna...
- 脈動 : [物理學] [天文學] pulsation; pulsing; pulse; ripple; impulsive motion; pulsating; panting; loping...
- 流速 : [機械工程] velocity of flow; strength; [水文] current velocity; current speed; flow rate流速管 pi...
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In this paper a kind of cardio - cerebral arterial bifurcation vessel hemodynamic characteristics are studied with the boundary element method, and the blood flowing velocity vector distributions have been calculated. in addition, the flow field distribution and the pressure on the particle surface are also calculated, when there is flow - round particle at the place of bifurcation, the move tendency of the particle is judged, the possible reasons of causing the atherosclerosis, thrombus, angioma are analysed
本文用邊界元方法研究了一類典型心腦動脈分支血管中血液流動的流體動力特性,計算了分支血管血液流動的速度矢量分佈,同時計算了分支附近有多個顆粒狀繞流物時血液的流場分佈,及顆粒物所受壓力狀況,給出了顆粒物的運動趨勢,分析了引起粥樣斑塊病變、血瘤、血栓的可能原因The experiment results indicate that this method is more effective in the brushless direct current motor ' s low speed torque ripple attenuation, and its more effective in improving system dynamic performance
運行結果表明,此方案能有效地抑制無刷直流電動機低速時的轉矩脈動,更好地改善系統的動態性能。This paper supplied a new way through variable frequency variable speed ( vfvs ) to change its output flow rate and adding a constant - pressure - drop valve, which could solve the defects in hydraulic pressure servo control system, such as low efficiency in control system, short life, poor ability in resisting pollution, low efficiency in driving system and flow rate, pressure pulse. and this way was proved to be effective
本論文針對傳統伺服控制系統效率不高、元件壽命短、抗污染能力差、驅動系統效率低、存在流量及壓力脈動等缺陷,利用先進的交流變頻調速技術改變液壓泵轉速的容積調速新方法,提出了在液壓系統中加一個定差減壓閥的新思路,較好地解決了液壓伺服系統存在的上述問題。In a study examining the impact of environmental cigarette smoke on heart blood vessels, japanese researchers found that 30 minutes of exposure to secondhand smoke reduced nonsmokers ' coronary flow velocity reserve ( cfvr ) - - a measure of the speed of blood flow
該研究調查了吸煙環境對心臟血壓的影響,日本研究人員發現暴露在二手煙環境三十分鐘可使不吸煙者冠狀動脈血液流速,這就是血液流速的測量值降低。The strong deviation and intermittence of the velocity and pressure fluctuations are found in the outer region about 3 ~ 4 times of the momentum thickness away from the mixing layer center, which are consistent with those observed experimentally
與實驗結果相符合,本文研究發現,在混合層邊緣約3 4倍動量厚度附近,流向和橫向速度以及壓力的脈動都存在強烈的偏斜和間歇現象。Results : the sonographic manifestations in the ipsilateral course variation vertebral artery revealed that the diameter and flow velocity were decreased, pi and ri were increased
結果:椎動脈走行變異其變異側椎動脈超聲表現為:管徑較窄, pi和ri較高,流速較低。Water feeding framework takes electromagnetism water valve as administration component and is added relief valve for stabilizing hydraulic pressure ; the system has large, middle and small water valve that changes unlock combination of electromagnetically operated valve, which can get seven different water flux ; if it is necessary, it should adopt microseism water feeding that can make water feeding get stepless timing
3加水機構加水機構採用電磁水閥作為執行元件,加入調壓閥穩定水壓,系統共設大中小三路加水閥,變化電磁閥的開啟組合,可以得出7種不同的加水流量,必要時採用脈動加水法,可使加水達到無級調速。Research on wind is the precondition of wind response, then the section plane of static wind, intensity of onflow, psd function and correlativity of dynamic wind are involved in
對風的研究是進行風振響應研究的前提,風的基本特徵包括平均風速剖面、湍流強度、脈動風功率譜密度函數、脈動風的空間相關性以及極端風速的概率統計特性。In the positioning servo - system, which generally is configured by the d. c. pulse width modulator ( pwm ) velocity governing system and position servo - loop, the parameter perturbance of pwm velocity loop really exist by reason of such as the load behavior ; power voltage supply ; operating setting value, etc. 1, 2 , and it cannot be ignored. by using the identification technique to form the mathematical model of the system, authors have confirmed the facts. therefore, to design the discrete sliding mode controller ( dsmc ) of the positioning servo - system, the perturbed parameters value bounds of the pwm velocity loop, which is as the controlled plant of position servo - loop, should be accounted. consequently, the design principle of dsmc for accounting system with parameter perturbance is proposed by the authors. the proposed method can ensure the stability of system with parameter perturbance and the behavior of non - overshoot, fast precise positioning. in order to reveal the effects of the design method, the comparative research work is done by the authors. also, it has been tested in an industrial experiment, the results proved it is satisfactory
由直流脈寬調速系統( pwm )和位置環構成的定位系統中,速度環的參數隨負載特性;電網電壓;給定工況而攝動是不容忽視的.作者通過系統辨識建模也證實了這一事實1 , 2 .因此在設計位置環的離散滑模控制時,必須針對速度環(即位置環的控制對象)的參數攝動范圍採用「對象參數攝動離散滑模控制器的設計方法」 ,以確保系統在參數攝動時的穩定性和快速、無超調、準確定位的優良動態品質.為剖析該設計方法的控制效果,本文作了對比性研究,並將該設計方法用於工業試驗中,取得了滿意的結果Velocity enhancement with ipc was similar between groups and the superficial femoral and popliteal veins
使用ipc ,股動脈和足部靜脈、動脈血液流速都增強了。Results : the peak and mean velocities, volume flow and pulsatility index in the superficial femoral and popliteal veins of both groups increased significantly with all ipc modes ( p < 0. 001 )
結果:兩個對照組使用ipc方法后,股動脈、腿部靜脈流速、流量的峰值和平均值,都有了明顯的提高( p < 0 . 001 ) 。The algorithm of svpwm that is adopted by the system implements motor speed - regulation by control of magnitude and phase of motor flux. it can generate less harmonics in the output current of power inverter and less losses of ac motor, reduce pulsant component in output torque and raise availability of dc supply voltage
系統採用的svpwm演算法通過對空間磁鏈矢量幅值和相位的控制來調節電機轉速,減少了逆變器輸出電流的諧波,降低了脈動轉矩,提高了電壓的利用率。The sediment - laden flow fluctuating velocimeter designed in this study has a well static and dynamic charateristic
本文研製的渾水脈動流速儀具有良好的靜、動態特性。Exploration and analysis of velocity slow down reasons of vertabral - basilar arteries via transcranial color doppler
基底動脈流速減慢的分析與探討By performing fourier transformation, the relationship between the turbulent intensity of the particle and that of the carrier fluid was obtained which makes clear that particle size, specific gravity, velocity gradient, and the characteristic frequency of energy - containing eddies are four basic influencing parameters. it is proven theoretically that under certain conditions, the stream - wise and transverse particle turbulent intensities exceed those of the carrier fluid. based on the equations of two - phase flow, the presence of fine sediment suspension is shown to attenuate the turbulent intensity of the water
通過對細小顆粒在剪切流場中運動方程的fourier分析,得到了顆粒脈動強度和流體脈動強度之間的定量關系,表明顆粒粒徑、顆粒密度、流速梯度以及紊動場含能旋渦的特徵頻率是影響顆粒脈動強度的主要因素,首次從理論上證明了在一定條件下,顆粒在縱、垂向的脈動強度均會超過相應的流體脈動強度,為已有的實測資料提供了合理的解釋。3. a three - dimensional - acoustic doppler velocimeter has been used to measure the velocity and turbulence in a compound channel with vegetated and unvegetated flood - plains. particulary in the interface region between main channel and floodplain. the distribution in three coordinate directions of velocity and turbulence intensities and the renolds stresses are presented. the momentum transfer at the main channel flood - plain interface can be described as an apparent shear stress which can be quantified as a function of the local turbulence at the interface
採用adv對灘地種樹前後灘槽交界區域的流速場進行了量測。分析了灘槽交界區域的垂線流速、紊動強度和雷諾應力的變化。將灘槽交界的動量傳遞描述為一表觀應力,這個表觀應力可以看作是交界面處的脈動函數並將其定量化。The turbulent flow in open channel is tested with laser - doppler anemometer, in which the longitudinal time average velocity and fluctuating velocity of turbulent flow in open channel under the conditions of the sudden changes of roughnesses at different water depths are measured
摘要通過激光測速儀,對壁面糙率突變時的明渠紊流進行試驗,測量了糙率突變不同水深情況下明渠紊流的縱向時均流速和脈動流速。The angiographic appearances included arterial occlusion ( 16 vessels ), extravasation of contrast ( 6 vessels ), intraluminal defects ( 3 vessels ), arteriovenous fistula ( 1 vessel ), arterial narrowing ( 5 vessels ), and slow arterial flow ( 9 vessels ), etc
血管造影的表現為動脈閉塞16條血管、動脈腔內缺損3條、對比劑外滲6條、動脈狹窄5條、局部管腔擴張2條、動靜脈瘺1條、動脈偏離3條、動脈血流速減低9條、局部動脈缺損處包塊染色1條。Under different positions of a tripping wire or speeds of the side jet, the controlled experiments were made, including the receptivity of the shear layer near jet exit to acoustic excitations, the spatial development of fluctuating velocity and the profiles of mean velocity
在不同絆線位置或不同旁射流流速條件下,研究了射流出口臨近剪切層對聲激勵的感受性,脈動流速向下游的空間演化及平均流速剖面。Dtc system is a high - performance adjustable speed system with fast torque response, but it still has some defects such as torque ripple, speed fluctuate and bad performance in low speed
該控制系統的轉矩響應迅速,是一種有高動態性能的交流調速方法。然而,直接轉矩控制仍存在轉矩脈動、轉速波動、低速運行性能差等缺陷。分享友人