自由振蕩 的英文怎麼說
中文拼音 [zìyóuzhèndàng]
自由振蕩
英文
force free oscillation-
Abstract : we have studied the spontaneous emission from a three - level atom with an external - driving field in a photonic crystal. as a result of quantum interference and photon localization, the population in the two upper levels displays quasi - oscillatory oroscillatory behavior. this depends on the initial atomic state and the relative positions of the two upper levels from the forbidden gap. the intensity and the phase of the external field can affect spontaneous emission from the atom. the properties are different from a three - level atom either in vacuum or in aphotonic crystal without an external driving field
文摘:討論了在雙光子驅動場作用下，三能級原子在光子晶體中的自發發射問題.由於量子干涉和光的局域化作用，兩個上能級中的占據數將具有周期振蕩或準周期振蕩的性質，這不僅依賴于兩個上能級與禁帶的相對位置，同時也依賴于原子的初始狀態，而且還與驅動場的強度、驅動場的入射位相有關.這些性質既與真空中帶有驅動場的原子的自發發射性質不同，也有別于無驅動場作用下光子晶體中三能級原子的自發發射性質The over - current relay works to protect oscillation tubes and rectifier, when the current exceeds its limits. frequency deviation caused by faulty operation is also prevented
當電流超過限制值時，過負荷電流繼電器自動保護振蕩管和整流器，同時可以避免由不當操作所引起的頻率漂移。We presents a detailed studied of the linewidth of parametric light in clbo - opo caused by the linewidth of pumping beam, off axis phase matching, divergence angle of pumping, time above threshold, high gain coefficient of nlo crystal, fluctuate of cavitylength, spontaneous radiation, according to the momentum and energy conversion laws, and the sellmeier equations of the clbo, we calculated curves of the type - i and type - ii compared with the bbo ' s
根據能量動量守恆關系和clbo的色散方程，詳細分析了由於泵浦光的線寬、泵浦光偏軸泵浦、泵浦光的發散角、泵浦光功率超過參量光振蕩閾值一定倍數、高增益系數、有效腔長波動以及自發輻射引起的參量光線寬，並得到了與bbo晶體在類、類相位匹配下比較的理論曲線。Based on the idea of subordinate meshes, we bring forward a new method of weighted volume which is used for constructing linear interpolation polynomials. besides, according to the eno interpolation on unstructured grids, a class of linear interpolation polynomial is developed on irregular quadrilateral grids and allows very small oscillation. program in fortran is given for a remapping algorithm developed by caiqingdong
另外，根據非結構網格的eno插值的思想，構造了四邊形網格網眼內的線性插值多項式，由於利用其插值點自適應選取的特性，在物理量變化劇烈區域選取最光滑區域的點來插值，雖然不能保持單調性，但只允許出現非常小的振蕩。Therefore it is considered that the spontaneous emission of atom is caused by the fluctuation of dipole moment, not by the dipole moment oscillation of the atomic system
原子偶極矩的期待值總是零，但偶極矩的起伏恆等於一個不為零的常數，因此，原子的自發輻射是由偶極矩的漲落引起的，並非原子偶極矩振蕩造成的結果。The states of the system and their differential signals are obtained on time by tracking differentiator, and the influence induced by nonlinear periodic load disturbance is compensated adaptively
電力系統混沌振蕩狀態和它的微分信號由微分跟隨器實時提取，並通過微分跟隨器對非線性周期性負荷擾動的影響進行自適應補償。The definition of the movement is composed by the forced vibration and self - excited vibration is presented, and verified
提出微操作器的粘滑運動由受迫振動和自激震蕩合成的思想。Because the self - oscillation, the dynamic accuracy of the servo system is not only correlative with servo system parameters but also influenced by the input signal amplitude, frequency and the system self - oscillation state
由於自振蕩狀態的存在，伺服系統的動態精度不僅與伺服系統的參數有關，還受到輸入信號幅值、頻率以及自振蕩頻率的影響。Traditional inertial mechanized - platform uses velocities to damp the system attitude to improve the precision of attitude, when the system acceleration is small. referring to the idea, this paper designeda damp kalman filter in strap - down attitude heading reference system ( ahrs ). the new method makes use of 3 - d accelerometer ' s measurements to estimate the system attitude, which is measured to compensate attitude errors. because the acceleration affected the precision of fiher directly, the fuzzy adaptive system was presented. the fuzzy logic inputs are three accelerations and the output is to control the measurement noise covariance matrix. simulations and experimental results prove that the damp algorithm can damp most of schuler oscillation and foucauh oscillation, so that to assure the filter convergence and efficiently improve the precision of strap - down ahrs
在系統機動性不強的情況下，傳統的平臺內阻尼演算法將系統本身的速度信息通過阻尼網路加到系統中，達到提高姿態角精度的目的.將這種平臺內阻尼的思想引入到捷聯慣性航姿系統中，在系統加速度較小的情況下，利用加速度計的輸出估計系統姿態角，通過卡爾曼濾波的形式補償系統姿態誤差.由於加速度的大小直接影響濾波器精度，本文設計了模糊自適應卡爾曼濾波演算法，根據三軸加速度計的輸出調整內阻尼量測誤差方差陣，從而避免了濾波器的發散.模擬和實驗驗證，內阻尼演算法可明顯抑制舒勒周期振蕩和傅科周期振蕩，避免了系統姿態漂移，有效提高了捷聯慣性航姿系統的精度First, we think periodicity and weakening surge of the nonlinear waveform is caused by self - excitation of the circuit. the electric field thresholds ( et ) and maintenance field ( es ) of lock - on are modulated by the ac electric field ; the nonlinear waveform became two main modes of trans - electron oscillator, namely delay polar domain mode and quenched dipole domain mode
指出非線性波形周期性的減幅振蕩，是由於光電導開關所處電路自激振蕩形成的交流場對偶極疇的閾值電場e _ t和維持電場e _ s進行控制，從而形成轉移電子振蕩器的兩種主要工作模式：延遲偶極疇模式和猝滅偶極疇模式。The goal of this subject is to sum up and exploit our technique how to produce low phase noise wideband vcos, through investigating and studying the basic theory and recent research fruits, combining national condition, and produce our low phase noise wideband vcos. using high q components, such as : coaxial resonator, dielectric resonator, makes bandwidth of vco become narrower, so that recently common wideband vcos generally make inductor and capacitor ( lc ) as resonators, combining varactors with wide range tunable capacitance, and achieve the wideband
本課題旨在通過對低相噪寬帶vco的基本原理、國內外在這方面的進展，結合國內的實際情況進行研究，總結和開發出自己的方法，形成自己的理論。並把它運用於實踐，以製造出低相噪的寬帶vco 。由於加入高q元件，如：同軸諧振器、介質諧振器等，會導致振蕩器帶寬比較窄，目前的寬帶vco一般採用電感電容（ lc ）作為諧振元件，輔之以大變容範圍的變容二極體，達到寬帶的目的。Since the concept of superlattice was proposed, vertical transport in superlattice has been investigated widely. the electric field domains and current self - oscillations which result from sequential resonant tunneling between different subbands of the superlattice are very significant phenomena. such kind of oscillation can be uesd to make tunable microwave oscillaors. in this thesis, low temperature transport problem, especially the formation of field domain and the condition of current self - oscillations in doped gaas / alas superlattice with weak coupling are investigated thoroughly and also by combining the macroscopic model with the microscopic one., the voltage - current characteristic and the current oscillation are simulated. the calculated result is nearly consistent with the experimental data
由超晶格中子能級之間的順序多阱共振隧穿引起的電場疇及電流自維持振蕩現象是其中的一個非常有意義的分支，該現象可用來製作電壓調諧微波振蕩器。本論文對弱耦合摻雜gaaa alas超晶格中的縱向輸運特別是針對低溫下的場疇的形成和固定偏壓下電流自維持振蕩產生的條件進行了深入的探討，並結合宏觀模型和微觀模型對超晶格在時變電壓作用下的電壓-電流特性以及固定偏壓作用下的電流特性進行了模擬計算。It will exert resistance and damping force to the torque motor armature, so that the dynamic performance, especially the stability, of flapper - nozzle servo - valve can be improved. the self - excited oscillations and noise can be removed. at the same time, as magnetic fluid has a higher magnetic permeability, the efficiency of torque motor magnetic circuit can be improved
由於磁流體具有的較大磁導率和較大的磁化強度，把磁流體添加到伺服閥力矩馬達的工作氣隙中，可提高伺服閥力矩馬達的磁迴路效率，增加伺服閥的阻尼，從而改善噴嘴擋板伺服閥的動態特性，抑制及消除其自激振蕩和噪聲。To the applications following the model, the self - driven performance optimizing, load adjusting, and vibration restraining can be archived in mobile network environment
基於這種模型開發的分佈對象應用可以有效地在移動網路環境中進行性能自主優化、負載調? ?配，並抑制由於網路變化可能造成的振蕩。分享友人