頻率速變 的英文怎麼說
中文拼音 [bīnlǜsùbiàn]
頻率速變
英文
frequency agility-
Mems ( micro electromechanical system ) has become one of the most rapidly development technologies. along with the rapid development of mems techniques, capacitive sensor is used widely whose capacitance changes small, which has put forward the new request to the measurement technique. the common measure for capacitance measurement is that convert capacitance to voltage, electric current or frequency. the area of polar plate of the capacitor becomes smaller and smaller, and the total capacitance of micro capacitive sensor is usually several pico farad only. as a result, its change amount is smaller
Mems （ microelectromechanicalsystem ）近年來發展最快的技術之一，隨著mems技術的快速發展，電容式加速度計的電容變化變化量越來越小，對檢測技術提出了新的要求。在電容式傳感器中，常用電容檢測電路是將其轉換為電壓、電流或者頻率信號。目前的微型電容傳感器的極板面積變得越來越小，電容總量只有幾個pf ，變化量就更小。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。Presents the energy saving principle of a frequency - controlled pump and points out the applicability of the law of similitude for centrifugal pumps and the conception of constant efficiency curves
摘要闡述了循環水泵變頻調速的節能原理，提出離心水泵相似定律的適用性和等效率曲線概念。By analysing the relationship among the parameters such as substrate, speed, tension, rotational speed, shape distortion of paper etc, this article put forward a control law to control the drive transmission roller in emery cloth and sand paper production line, the principle is based on hooke ' s law
摘要本文根據彈性力學中的虎克定律，結合砂布砂紙生產特點，分析計算了生產線中基體、應變、速度、張力、轉速等參數之間的關系，建立了砂布砂紙生產線中傳動輥轉速（頻率）運動方程。The experiment apparatus has been developed, which is based on software ( labview ) and hardware ( pci board ni 6024e ). the displacements and generative force at the tip of the ipmc actuators were measured with respect to the different voltages, frequents and various waveforms which include square, sinusoidal, and triangular wave
實驗選取了不同電壓幅值，不同頻率的方波、三角波、正弦波三種波形作為電激勵信號，利用高速攝像記錄ipmc的位移變形，並通過力傳感器實測了ipmc試樣末端的輸出力。For short wavelengths, approaching the intermolecular distance, the velocity can vary with wavelength
而對于波長短到接近分子間距離的波，其速度則會隨頻率而改變。The specific research methods are listed : 1. matched filter taking the max ouput snr as the best rule correlates nonstop divided signal and divided echo to detect low snr target signal. then all one dimension divided correlation outs and done fft in portrait to leach interferential signal such as static or low rate mussy meaves, many pathway echo and so on and to take target ' s time difference and doppler frequency that combine parameters that target ' s direction taken from antenna and so on to implement target ' s orientation and tracking
具體研究方法如下： 1 、採用以輸出信噪比最大為準則的最佳匹配濾波器來對分段的參考和目標信號作相關處理來檢測低信噪比目標信號，然後對一維分段相關輸出組作縱向傅立葉變換來濾除靜態或低速的雜波、多徑回波等干擾信號，並提取目標的時差和多普勒頻率，再結合由天線獲得的目標方向等參數，就可以實現目標的定位和跟蹤。Electric - controller is nubbin in developping. we are based on designing to structure of circuit, we are dead against in time and stabilization for controlling and communications, precision and rapidity for transformation etc. we have completed to select on microprocessor, clock - frequency and a / d transfer. it carry out transformation for valve position signal, and select on solid - switch ac
在控制器的電路結構設計的基礎上，考慮到通訊、控制的及時、穩定、轉換的精度和速度等幾方面，主要完成對微處理器的選擇、時鐘頻率和a d轉換器的選用，閥位變送功能的實現，固態交流開關和顯示器的選擇等。By making full use of favourable narrow - band tracing filter character of pll and by combining the merits of dds such as super fine frequency resolution 、 high frequency accuracy 、 very fast frequency hoping with it, the pll / pll + dds frequency synthesizer presents wide band high quality source and super small frequency hoping step. while the electronically tuned filter abates the image interference and notably improves the selectivity. the theorem of frequency synthesizer and center - frequency - fixed filter is simply but adequately introduced first in this paper
課題中所採用的pll或dds pll鎖相頻率合成方法充分發揮鎖相環良好的窄帶跟蹤濾波特性，並結合dds的高頻率解析度、高頻率精確度和高速頻率捷變等優點，分別實現了系統所要求的高質量寬帶本振源和小步長頻率捷變；採用電調諧選頻技術，則大大改善了接收機的選擇性和抗干擾能力。Considering the similitude law for shaking table test, we study the test results and obtain some conclusions which are a ) generally, the silty soil in test box liquefies and the liquefied time has relation with the amplitude of acceleration, b ) when the intensity is on and above eight degree, the silty soil deposit will be liquefied dramatically, c ) the relationship of the pore water pressure is relevant to the cycle loading which represents when the cycle loading ranges from little to great, the relationship is represent as a concave curve, or else as a protruding curve and tends to stability. ( 3 ) based on the triaxial compression test and the resonant column test, some studies are made such as a ) the duncan - chang parameters of constitutive model, b ) the dynamic shear modulus ratio and c ) the damping ratio of the site soil deposits. in order to deal with the test data, a computer program is compiled
（ 2 ）利用小型振動臺進行了k _ 0固結狀態下粉土的振動液化模擬研究，通過分析正弦荷載作用下的試驗資料，驗證了粉土的孔隙水壓力增長模式的合理性；從微分方程推導了基於土體振動臺模型試驗的相似律，並從模型實體、孔壓時程曲線和相似律等方面做出了分析，得出了如下結論：在小型振動臺試驗中，模型箱中的粉土都發生了液化，液化的時刻和輸入加速度幅值有關，而對頻率的變化不太敏感；粉土在相當於8 9度地震烈度的加速度幅值作用下可能產生嚴重的液化；孔壓的增長曲線形狀與施加的荷載有關：當施加荷載為由小到大的形式時，曲線形狀為上凹的曲線；當施加荷載為等幅的正弦荷載或荷載幅值由大到小時，曲線形狀為上凸的曲線，且逐漸趨于穩定。Because direct torque control requires very high performance of real - time, the popular microcomputer core dsp is used as controller in the design of hardware. its high speed of running is suitable for the experiment. in the main circuit, there is a highly integrated power element : ipm as inverter, which includes seven igbt, has high switch frequency and fault diagnosis function
在本控制系統的具體實現上，由於直接轉矩控制對實時性要求很高，因此在硬體方面，採用了目前比較流行的數字信號處理器（ dsp ）作為系統的控制器，其處理速度高的特點正好符合本實驗的需要：在主電路中，本系統使用了集成度高的功率器件：智能功率模塊（ ipm ） ，作為逆變環節，其集成了七個igbt ，實現了高開關頻率逆變以及故障診斷的功能，從而使控制系統的體積大大縮小、控制更加靈活。Due to the direct torque control requires very high performance of real - time, the popular microcomputer core dsp is used as controller in the design of hardware. its high speed of running is suitable to the experiment. in the main circuit, there is a highly integrated power element : ipm as inverter, which includes seven igbt, has high switch frequency and fault diagnosis function
在本控制系統的具體實現上，由於直接轉矩控制對實時性要求很高，因此在硬體方面，本課題採用了目前比較流行的數字信號處理器（ dsp ）作為本實驗的控制器，其處理速度高的特點正好符合本實驗的需要；在主電路中，本系統使用了集成度高的功率器件：智能功率模塊（ ipm ） ，作為逆變環節，其集成了七個igbt ，實現了高開關頻率逆變以及故障診斷的功能，從而使控制系統的體積大大縮小、控制更加靈活。We apply fuzzy control theory to active control over engine body vibration, design fuzzy control system which combines intelligent control with feedback control. this control strategy mends the flaw of complexity, nonlinear and uncertainty when we use traditional control method. by measuring rotate speed and vibration speed of i. c
在主動控制的基礎上，採用了模糊控制的演算法，設計了內燃機整機振動模糊控制器，改進了傳統控制方法在處理振動復雜性、非線性和不確定性等方面的缺陷，通過測量內燃機轉速和內燃機整機振動速度信號，動態地改變動力減振器的剛度，使減振器的固有頻率跟隨內燃機整機振動激勵頻率的變化，達到降低內燃機振動的目的。This conclusion does not support the viewpoint that the slip of an induction motor with frequency speed control is constant
研究表明，變頻調速電動機的轉差率隨頻率的變化而變化，本研究的結論否定了變頻調速電動機轉差率不變的觀點。It will be affect the range processing that the frequency agile of carrier in frequency agile signal arouse the variety of doppler frequency, so the compensate of velocity door is obligatory
跳頻信號中載頻的跳變會引起多普勒頻率的變化，這對距離的處理產生影響，必須進行速度門的處理。Then, by seismic numericac simulating of the buried hill surface and its internal phase and analysis of characteristic of wave - field, the wave - field charalteristic of the buried hill ' s surface is different to the characteristic of the buried hills " internal phase, and the change of amplitude and frequence is bigger than that of velosity which proves further that dynamical characteristic is more sensitive to fracture than kinetic characteristic
進而通過潛山面和內幕地面地震記錄的數值模擬和波場特徵分析表明，潛山面和潛山內幕裂縫介質的波場特徵是不一致的，振幅和頻率的變化量大於速度的變化量，從而更進一步證明，對于裂縫的敏感性，動力學特徵優于運動學特徵。( 2 ) because of t he variability of rock subjected to outside action, three new conceptions : postive damage basic damage and negative damage, are suggested, which can deal with the condition that rock density became large. ( 3 ) the present damage variables based on ct number mostly include ct average number of the rock without damage, which is difficult to measure, so a new damage variable, which includes the average ct number is proposed, on the other hand, strain equal theory is generalized because the one put foreword by lemaitre is not good enough to use. ( 4 ) a axial damage constitutive equation is proposed and testified. ( 5 ) with the circle times, the damage propagation laws of two different rocks, subjected to circle of freezing and thawing, are studied, and in the analysis process, traditional analysis method including average ct number and is used, some important conclusions are reached : inner damage of soft rock containing a large mount of apertures is largely propagating with the time increasement of circle, however, at the preliminary time, the hard rock containing a small mount of aperture is a little propagating, at late time, the influence become large ; ( 6 ) zone separation and statistics frequency put forward is used to analysized the three different damage propagation in the open circumstance, when they are subjected to the different circle times of freezing and thawing, in which the temperature variability is linear, different freezing rate, and different freezing temperature, and no water is supplied during the test
在研究過程中本文主要做了以下工作： （ 1 ）針對巖石損傷變化較小時，運用ct均值和方差分析不方便的缺陷，本文提出運用對ct數范圍劃分區段的方法，根據各區段統計頻率的變化規律來分析損傷擴展狀況； （ 2 ）針對巖石受到外部作用的多變性，本文提出了基準損傷，正損傷，負損傷的概念，在某種程度上考慮了巖石受到外部作用時的壓密情況； （ 3 ）現有的基於ct數的損傷變量大多需要用到巖石基體的ct均值，這實際上是很難觀測到的，因此本文建議了一個可運用巖石初始狀態ct均值的損傷變量，由於現有的勒邁特教授應變等價原理使用上的不便，本文在其基礎上進行了推廣； （ 4 ）建議了一個可用巖石初始狀態ct數和彈性模量的單軸損傷本構方程，並用算例進行了驗證； （ 5 ）對兩種不同巖石在開放環境下受到凍融循環作用且融化過程中補水時，內部損傷隨凍融循環次數增加的擴展規律進行了探討，主要運用了常規的ct均值和ct方差的分析方法進行分析，試驗發現：對于孔隙率和含水率較高，密度和強度較低的軟弱巖石，凍融循環次數對損傷結構的擴展有明顯的影響，而對于孔隙率和含水率較低，密度和強度較高的硬巖，凍融循環次數對其損傷結構擴展初期由於含水率低的原因，影響不是太大，而後期由於水補給后，含水率較高的原因，凍融影響逐漸增大； （ 6 ）運用了本文提出的區段劃分和統計頻率的方法，深入地分析了開放環境下的線性溫度變化的凍融循環次數，凍結溫度，凍結速度不同巖石作用時，其內部損傷隨凍融循環次數，凍結速度和凍結溫度變化的擴展規律，需要指出的是除了在試驗前飽水外，凍融過程中沒有補水。Frequency ’ s switching time, which directly affects the hopping speed of interferential system as well as radar ’ s frequency agility, is being paid more and more attention. this paper mainly analyzed the frequency synthesizer ’ s agile character
其中，捷變時間這一指標，由於直接影響到跳頻干擾和抗干擾系統的跳速，以及雷達頻率捷變特性，越來越受到人們的關注。By experiment, we found that the variation of gear case radiant efficiency with frequency keep accordance with that of simple one as a whole, but the radiant efficiency of gear case will go beyond any calculation result of empirical formula when the frequency is below 250hz. we also found that stimulation changes affect radiant efficiency little by varying speed experiment, and it can be ignored in engineering calculation. the rectangle structures as gear case, possess characters of both plane and ball, and their sound radiant efficiency lie between plane and ball region
通過試驗發現，總體上變速箱輻射效率隨頻率的變化規律同簡單構件的輻射效率是一致的，但在250hz以下的低頻區域，變速箱的輻射效率大大高於任何一個經驗公式的計算結果；通過換檔試驗發現，激勵的改變對輻射效率的影響不很顯著，工程計算可以不予考慮；對于變速箱這類三個方向尺寸差別不大的結構，其輻射性質具有平板和球源的雙重特徵，輻射效率介於平板和脈動球源之間，據此提出在工程應用時可以取平板和脈動球源輻射效率的平均作為此類結構輻射效率的觀點。Synthesizers with low phase noise, highly pure spectrum, high resolution and fast frequency jump speed have dominating development direction of the frequency synthesis technology
低相位噪聲、高純頻譜、高解析度和高速頻率捷變成為頻率合成技術發展的主要趨勢。分享友人