振蕩學 的英文怎麼說
中文拼音 [zhèndàngxué]
振蕩學
英文
turbulence-
Afterburner systems, designed to operate up to a stoichiometric overall mixture strength, are always fairly close to combustion instability or screech.
要使加力燃燒系統在理論化學組成量的總混合濃度下還在一直工作，這樣的設計通常都很接近於不穩定燃燒或振蕩燃燒。The near - stoichiometri litao3 has excellent speciality, such as high efficient conversion, tune conveniency, biger size and high damnify value etc. in this dissertation, the theory of quasi - phase - matched ( qpm ) technology and optical parametric oscillation ( opo ) was expatiated and studied first
近化學計量比litao3 （ slt ）晶體在做參量振蕩方面具有轉換效率高、調諧方便、尺寸大、損傷閾值高等非常好的特性。本文首先對準相位匹配技術和光學參量震蕩器的理論進行了闡述和分析。Laser diode or flash lamp pumped solid state lasers with different wavelength and different operating styles. wavelength tunable laser sources with tial2 o3 laser and optical parametric oscillator laser application machines with laser display, laser material procession
各種波長及各種運轉方式的激光二極體及閃光燈泵浦的固體激光器；採用鈦寶石及光學參量振蕩器的波長可調諧的激光光源；激光應用整機。According to sedimentary characteristics of the carboniferous taiyuan formation in feicheng coal field, including lithology, size distribution, sedimenta ry structure, geochemistry and paleontology etc., the carboniferous paleoenvironme nt of this area is divided into carbonate open platform and tidal flat environme nt. it is recognized that the taiyuan formation is formed in the epicontinental c oast which is dominated by the tidal. the peat flat is the important paleoenviron ment for coal accumulation. the tidal channel destroys the coal bed. the pulsative vibration of the crust is the major factor which controls the evolution of the sedimentary environment and the coal accumulation
根據肥城煤田石炭系太原組的巖性、粒度分佈、沉積構造、地球化學及古生物等沉積特徵，將該區晚石炭世古地理劃分為碳酸鹽開闊臺地和潮坪環境，認為太原組形成於潮汐作用為主的陸表海海岸，泥炭坪是成煤的重要古地理環境，潮渠對煤層有一定的破壞作用，地殼的脈動性振蕩作用是控制沉積環境演化和聚煤作用的主要因素。Abstract : according to sedimentary characteristics of the carboniferous taiyuan formation in feicheng coal field, including lithology, size distribution, sedimenta ry structure, geochemistry and paleontology etc., the carboniferous paleoenvironme nt of this area is divided into carbonate open platform and tidal flat environme nt. it is recognized that the taiyuan formation is formed in the epicontinental c oast which is dominated by the tidal. the peat flat is the important paleoenviron ment for coal accumulation. the tidal channel destroys the coal bed. the pulsative vibration of the crust is the major factor which controls the evolution of the sedimentary environment and the coal accumulation
文摘:根據肥城煤田石炭系太原組的巖性、粒度分佈、沉積構造、地球化學及古生物等沉積特徵，將該區晚石炭世古地理劃分為碳酸鹽開闊臺地和潮坪環境，認為太原組形成於潮汐作用為主的陸表海海岸，泥炭坪是成煤的重要古地理環境，潮渠對煤層有一定的破壞作用，地殼的脈動性振蕩作用是控制沉積環境演化和聚煤作用的主要因素。It will be apparent in the mathematical notes that under some conditions the solution is not oscillatory.
在數學附錄中可以看到，在有些條件下，這個問題的解是不振蕩的。In this paper, high - order accurate weighted essentially non - oscillatory ( weno ) schemes are investigated and their applications in hyperbolic conservation laws are discussed. based on this, a new weno difference scheme which based on dispersion - relation - preserving relation is developed, and representative test cases with this scheme for computational aeroacoustics ( caa ) problems has been implemented and compared in order to test capability of wave capturing ; in addition, weno schemes generally do not converge at high order in the presence of contact discontinuity of euler equations, so a conservative front tracking technique coupling weno schemes and level set method to simulate the translating density profile is presented here, and numerical simulation with this technique for representative test case has been implemented and results show the desired accuracy
本文研究了高階精度加權基本無振蕩（ weno ）格式及其在雙曲守恆律方程中的應用，在此基礎上作了兩個方面的工作：一是針對高頻聲波問題構造出一種基於保色散關系（ drp ）的weno有限差分格式，並對計算氣動聲學（ caa ）問題的代表性算例進行了大量數值實驗，比較了該格式捕捉波數的能力；另外，針對高階weno格式在處理euler方程的接觸間斷時精度有所降低的問題，研究了利用界面追蹤技術levelset方法和高階激波捕捉weno格式相結合的一種守恆追蹤方法，並且給出有代表性的密度滑移面問題的算例，得到一致高階精度的數值模擬結果。It has been shown that : the little indentation which represents the quantum noise of the system appears in the evolution curves ; the quantum noise which is caused by virtual photon field gradually becomes weak when w increases, the quantum noise increases when n increases ; the virtual photon process make the antibunching effect strengthen, make the squeezing degree deepen obviously, and lead to the additional vibration of entropy, the oscillation extent of the additional vibration of entropy increases when n increases and decreases when co or g increase. besides, the quantum dynamics of two coupling atoms interacting with a single mode ligh t field in a kerr medium is studied in this paper ; the influences of the kerr effect on the mean photon number, the degree of second order coherence of field, the evolution of the field entropy and the squeezing effect are also discussed
）的增大，量子噪聲分別減小和增大；虛光子過程使光場的反聚束效應增強，使光場的壓縮程度明顯加深，並引起了附加的「熵振蕩」 ，這種附加「熵振蕩」的幅度將隨著光場初始平均光子數（ ? ）的增加而增大，隨著光場頻率和原子間耦合系數g的增大而減小。本文還研究了充滿kerr介質腔中「耦合雙原子-單模光場」相互作用系統的量子動力學性質，研究了克爾效應對場的平均光子數、二階相干度、場熵演化特性及光場壓縮效應的影響。The numerical simulation of axisymmetric two - dimensional shock tube is studied, which has a conical convergent section, and its driving gas is the hot product of hydrogen oxygen detonation. finite volume tvd scheme is adopted and the mesh is local orthogonal. the primitive equations are euler s equations of multi - component flow. the new method of eliminating numerical oscillation at the interface of two materials is extended to two dimensions. the mechanical character of this shock tube is analyzed
對由前向爆轟產生驅動氣體並具有局部錐形收縮截面的軸對稱激波管利用兩相常比熱完全氣體的歐拉方程組和有限體積tvd格式在局部正交的網格上進行了二維數值模擬。將消除兩種介質界面處數值振蕩的新方法成功地推廣到二維情況。分析了該激波管的力學特性。According to the guidline, two nd : yag lasers have been designed and set up, one is end - pumped by lower output power ld using a selfoc micro lens, and the other is end - pumped by high output power ld using a pair of lenses are designed, and the characteristics such as output power and power stabilization of both solid - state lasers are investigated. thirdly, when an empty liquid crystal cell is inserted in the cavity of the nd : yag laser pumped by high power ld, the laser can operates in single axial mode. finally, according to the relationship between the laser output power and the longnitudinal a ld - end - pumped nd : yag laser sensor for displacement measurement has been investigated theoretically and demonstrated experimently, the results indicate that when the mean radius of pumping inside the laser cavity is far less than that of the oscilating laser mode, the exponential of the output power is a gauss function of the longitudinal positon of focused spot of ld pumping beam, both the measurement range and the sensitivity are dependent on the incident pumping power, as the incident pumping power is increased, the measurement range is enlarged and the sensitivity is improve d
本文首先介紹了ld泵浦nd ： yag激光器的發展狀況、主要特性及其應用，從四能級速率方程出發，推導了ld泵浦nd ： yag激光器的閾值、輸出功率和斜效率的表達式，並簡述了激光器的工作原理、結構型式和倍頻方法；其次，以空間相關的速率方程為基礎，提出了ld端面泵浦nd ： yag激光器的設計方法，給出了一定泵浦耦合方式下，振蕩光模尺寸、最佳輸出耦合率、泵浦光模尺寸、泵浦光焦斑位置等參數的選取依據，以此為依據，設計了自聚焦透鏡耦合小功率ld泵浦nd ： yag激光器和透鏡組耦合高功率ld泵浦nd ： yag激光器，對激光器的輸出功率和功率穩定性等特性進行了實驗研究；再次，在帶尾纖輸出的高功率ld泵浦nd ： yag激光腔內插入一隻空液晶盒，觀察到了激光器以單縱模運轉；最後，根據泵浦光焦斑端面位置對激光輸出功率的影響規律，提出了ld端面泵浦nd ： yag激光位移傳感新方法，並進行了理論和實驗研究，研究結果表明：當激光晶體內泵浦光平均光斑半徑遠小於振西安理工大學碩士學位論文蕩光束腰半徑時，激光輸出功率的自然指數與泵浦光焦斑的縱向位置成高斯變化規律，測量范圍和靈敏度依賴于泵浦功率，隨著泵浦功率的增加，測量范圍擴大，靈敏度提高，當端面泵浦功率為7 . 24w （最大輸出功率為1 . 926w ）時，激光位移傳感器的測量范圍和靈敏度分別是13 . 045mm和0 . 148mw / pm 。In this dissertation, two kinds of optimization, methods are proposed. firstly, only these linking weights corresponding to the control rules that affect the control performance significantly are updated in order to reduce the compute works and speed up the training progress. secondly, the updating step is adjusted adaptively in accordance with the error and the change of error of the system based on the t - s model to get better performance
針對模糊神經網路控制器一般存在著在線權值調整計算量大、訓練時間長、過度修正權值可能導致系統劇烈振蕩等缺點，提出了兩種模糊神經網路控制器的優化方法：在線自學習過程中僅對控制性能影響大的控制規則相關的權值進行修正，以減小計算量，加快訓練速度；基於t - s模糊模型，根據偏差及偏差變化率大小動態自適應調節權值修正步長，抑制控制器輸出的劇烈變化，避免系統發生劇烈振蕩。During the circuit design, the author analyzed the basic principle of the direct current motor, pwm control, h - bridge power driver, and two control techniques of h - bridge power drive circuit, designed its general structure, so the feasibility of the design is confirmed. then, reference, oscillator, power dmos gate drive circuit ( charge pump, bootstrap ), and dead time generation circuit are designed and analyzed in the sub - circuits. a current - controlled oscillator is presented in this thesis
在電路設計中，作者介紹了直流電機的工作原理和數學模型、脈寬調制（ pwm ）控制原理、 h橋電路基本原理和h橋功率驅動電路的兩種控制模式，設計了驅動電路的總體結構，給出了電路的功能模塊，確定了設計的可行性，然後在子電路模塊中，重點分析設計了基準源電路、振蕩器電路、高端功率管柵驅動電路（電荷泵及自舉電路） 、低端功率管柵驅動電路和死區時間產生電路。Theoretically, on the bases of the physical and chemical characters of nonlinear frequency - conversion crystal ktp, the parameters such as walk - off angel, acceptance angle and effective nonlinear coefficients are calculated, analyzed and discussed, together with elaborate analysis to phase - matching process for type ii ktp opo phase - matching
在晶體的光學性能方面，根據ktp的物理和化學性能，對它的有效非線性系數、走離角和接受角等參數進行了計算、分析和討論。對ii類相位匹配的ktp晶體在參量振蕩過程中的相位匹配進行了詳細的分析和計算。Based on the potential resonance in heavy - ion collisions, the anomalous phenomenon of the backward - angle oscillatory arising in the angular distribution for 16o + 12c elastic scattering have been studied within the framework of the optical model using a deep optical potential
摘要基於重離子碰撞中勢共振的考慮，在光學模型的框架下，使用深光學勢研究了16o + 12c彈性散射角分佈后角振蕩上升的反常現象。The harmonic balance simulation and envelope simulation are applied in the cad progress of pulse oscillator, the results of simulation are listed, and the output signal of pulse oscillator is analyzed by mathematical method
以脈沖振蕩器的cad為例，對脈沖振蕩器分別進行諧波平衡模擬和包絡模擬，列出了模擬結果，並對脈沖振蕩器輸出信號進行數學分析。There are five parts are as follows : in part one, the concept of switching function is introduced first to establish the nonlinear mathematical model of the induction motor variable frequency speed adjustment system which is fed by a sine pulse width modulated ( spwm ) inverter and takes the effect of the main magnetic circuit saturation into consideration, then the low frequency oscillation of the system is simulated according to the model. next, from the view point of energy conversion of the inverter - induction system, a criterion for the low frequency oscillation is proposed to determine whether the system is in low frequency oscillation which is judged by whether the interval of the negative current component of the inverter input current is more than 1 / fc ( fc is the carrier wave frequency of the inverter ) or not
首先引入開關函數概念，建立了正弦脈寬調制（ spwm ）逆變器供電異步電動機，考慮主磁路飽和時的變頻調速系統整體數學模型，模擬系統的低頻振蕩；其次從逆變器-異步電動機系統能量轉換角度出發，提出通過檢測逆變器輸入電流中負電流的間隔時間是否大於1 / f _ c （ f _ c為逆變器載波頻率）來判定系統是否出現低頻振蕩；最後的實驗結果驗證了系統低頻振蕩建模和判據的實用性和正確性。Through the deep study of f. d. demello dynamic model of electromechanical transition and synchronous generator theory, we proposed a new control strategy of excitation device that can eliminate the negative - damping phenomenon, which is directly against the cause of producing negative - damping represented as low frequency oscillation in the system
通過深入研究f . d . demello機電暫態的動力學模型以及同步發電機理論，針對系統產生負阻尼即低頻振蕩的原因，我們提出了一種新的可消除負阻尼現象的勵磁控制策略。The characteristics of damping shows that the uncompensated parallel ac transmission line can release the coupling between the hvdc and generator and improve the damping of the system, hence the possibility of subsynchronous oscillation decrease. in such a system scheme, the hvdc system dominates the changes of damping due to the small magnitude of the damping provided by ac line. when the ac transmission line is compensated with a fixed series capacitor, the situation will be totally different
其中，並列運行的無串補交流輸電線路可以緩解hvdc與其臨近機組之間的機電耦合程度，改善hvdc的電氣負阻尼特性，從浙江大學博士學位論文摘要而減輕機組發生次同步振蕩的危險性，此時系統的整體電氣阻尼特性由hvdc的性質決定;但若交流線路中存在串聯補償電容，則系統幅值較大的電氣負阻尼不僅可能使整流站機組發生次同步振蕩，逆變站附近機組同樣存在發生次同步振蕩的可能性，此時系統的整體阻尼特性由串聯補償電容的性質決定。In the section of experiment, we focused on the research of optical system of optical parameter oscillation, computer controlling data sampling closed - circuit system and technology of computer controlling feed - back. in the section of optics, we used present condition to do the experiments about optical parameter effect and got a series of characteristic curve on power transition efficiency and output power
本文的實驗部分主要側重於智能化光參量系統的光學部分、計算機控制數據採集閉環系統以及計算機控制反饋技術的研究。在光學部分，本論文利用現有實驗條件進行了參量振蕩器頻率調諧的研究，得到了調諧曲線，並做了輸出參量光的能量轉換效率以及輸出功率的實驗，得到一系列特性曲線。Polarization characteristics of laser beam, which is one of the important characteristics of high power laser, have a direct effect on output power, damage threshold of optical elements and beam quality etc. the polarization characteristics in the high power coil resonator is analyzed by jones calculus, and draw a conclusion that, in general the eigen - polarization state is elliptical polarization
激光光束的偏振特性是高功率激光器的一個重要特性之一，直接影響著高功率激光器的輸出功率、腔內光學元件的損傷以及光束質量等。本文首先利用瓊斯矩陣演算法對高功率氧碘激光器腔內的偏振特性進行了分析，並得出結論，諧振腔內的本徵振蕩一般為橢圓偏振。分享友人