頻率下限 的英文怎麼說
中文拼音 [bīnlǜxiàxiàn]
頻率下限
英文
lower frequency limit-
The brief name ring, measures a device right high, inside, low and each segment scope for ability for even emersion of signal, pointing lowestly validity returning putting the frequency with tallestly validity returning put of the frequencying. request towards device rang contain both side, on is a scoping as far as possible breadth, can be namely frequency bottom that replay the is as far as possible low, and the upper limit is as far as possible high ; two is a frequency scope the inside is at all point to respond to as far as possible flat, avoided to appeared the big motion
簡稱頻響，衡量一件器材對高中低各頻段信號均勻再現的能力，指最低有效回放頻率與最高有效回放頻率之間的范圍。對器材頻響的要求有兩方面，一是范圍盡量寬，即能夠重播的頻率下限盡量低，上限盡量高二是頻率范圍內各點的響應盡量平坦，避免出現過大的波動。In all kinds of complicated network, oriented linking and unlinking, communication frequency resource is strained, and bandwith to transmitting audio frequency signal is too restricted, complicated and fluky, while audio frequency data exponential have been increased in the last several years. under the circumstances, based on the research of predecessor, this paper studies wavelet analysis ' s maths gist and practices significance on signal process, and puts forward a optimized wavelet package condensation arithmetic to process audio frequency data, which gives attention to coding efficiency, multirate and compression delay. simulation experiment on the arithmetic has been done by matlab
針對無連接和面向連接的各種復雜網路環境下，通信頻帶資源緊張，音頻傳輸帶寬有限且復雜多變，而各種音頻數據又日益增多的局面，本文研究小波分析在信號處理方面的數學依據和在數據壓縮方面的實際意義，在前人不斷工作的基礎上，提出了一種優化小波包變換編碼方案用於音頻數據的壓縮演算法，兼考慮了編碼效率、多碼率和壓縮時延多個方面，並在matlab環境下做了模擬實驗，對各種音頻信號及多種小波函數做了模擬結果比較，實驗結果證明該演算法可以在一定計算復雜度下可以很好地改進壓縮效果，達到多碼率下實現實時編解碼的過程，在高速dsp晶元等硬體設備支持下，可以有效應用於實際復雜多變信源編碼。Choose two nodes on the edge of the structural to compare the results calculating by the finite element program midas, then we can draw a conclusion that these kinds of space truss systems is sensitive to the libration of the dynamic wind loads. to consider this factor is very necessary in the process of design, we will use the pulsant augmentation coefficient to realize it
比較靜力風荷載和動力風荷載作用下的有限元軟體的計算結果，選取結構邊緣部分的兩個節點，對比它們在兩種方法計算下的最大位移的計算結果。經過比較可以看出重量輕、頻率低、阻尼小的柔性建築物對風荷載的橫向振動是很敏感的，在進行工程設計時應該考慮這種因素，並可採用乘以風振系數等相應方法來加以體現。The amplitudes of the two ffts are the same, but their phases, < px and < p2, changes with the range differently
Rao下限，在信噪比為6db ， fft長度為1024的情況下，頻率估計均方根誤差小於fft頻率解析度的1 。Shortwave channel is time varying transmission channel. it has dispersion in frequency and time domains. this characteristics hinds the data transmi - ssion at high speed and the correction of received data. in this dissertation i have analyzed the statistic characteristic of shortwa - ve channel, established the model of shortwave channel and simulated the rayl eigh fading distribution. the technology of spreading spetrum has been proved that it has the capability for anti - multipath and discerning multipath
在短波通信中，由於通道的時間色散和頻率色散，引起多徑展寬和多徑衰落，前者限制了數據的傳輸速率，後者造成短波數據通信中出現突發錯誤，為了解決多徑效應對短波通信的影響，本文所做工作如下：首先詳細分析了短波通道的統計特性，建立其數學模型；其次分析了擴頻通信的特點，從理論上證明擴頻技術不僅具有抗多徑干擾能力，而且具有分離多徑的能力；介紹了傳統的rake分集合併技術的特點。The notable torsion effects of the surface ground motion above the alluvial valley are illustrated and the torsion effects become stronger as the frequency of the incidence is higher. ( 4 ) antiplane surface motion of the underground circular soft inclusion and the underground homogeneous soft interlayer is investigated in this paper. the results indicate : surface displacement amplitudes just above the soft inclusion of small depth - to - width ratio is amplified and soft interlayer of small depth - to - thickness ratio is amplified to a certain degree, and moreover, the latter is lower limit of the former
結果表明：垂直入射時，小深寬比軟夾塞上方地表位移幅值有較大的放大，小深厚比軟夾層的地表位移幅值也有一定的放大，且後者為前者的下限；波接近掠入射時，軟夾塞正上方地表點和軟夾層的中國地震局工程力學研究所碩士學位論文一地表位移幅值都沒有放大，而軟夾塞迎波面一側地表點的位移幅值會有一定的放大；軟夾塞上方的地表位移運動有較強烈的扭轉效應，且此扭轉效應隨入射波頻率的增高而增強。In the two - photon resonance case, part of the input pulse energy is transformed into higher and lower frequency components through amplified spontaneous emission and four - wave mixing, and the medium shows strong optical power limiting effect
在雙光子共振情況下，即入射脈沖頻率等於1 、 3能級之間的共振頻率的一半，由於介質中放大的自發輻射和四波混頻的作用，部分入射脈沖能量轉化為高頻和低頻電場成分的能量，分子介質表現出了很強的光功率限幅特性。Our treatment shows in the raman effect case, mnls solitons, the same as nls solitons, keeps its energy, initial center and initial phase unchanged. however, the raman effect, not the same as nls solitons. reduces its amplitude, widens its width and under the same conditions, the self - frequency shift of mnls soltions is closer to the result of numerical simulation. in the raman effect together with frequency filters case, mnls solitons, the same as nls solitons, keeps initial center and initial phase unchanged and bandwidth - limited frequency filters can make the mean frequency of mnls soltion stand a steady value at the red side of the initial mean frequency, i. e. suppress the self - frequency shift of mnls soltions. and that, the other physical parameters of mnls soltion last stand a steady value. however under the same conditions, the steady value of the mean frequency of mnls soltions is closer to the initial mean frequency and the result of numerical simulation
有所不同的是， raman效應雖然不改變孤子能量，但會引起孤子峰值的下降和寬度變寬，且在同一條件下， mnls孤子微擾理論得到的自頻移比nls孤子微擾理論得到的更接近直接數值計算結果。有限帶寬的頻率濾波也不引起mnls孤子初始中心、初始位相的改變，選取適當的頻率濾波器參數值能使孤子的平均頻率穩定在初始平均頻率的紅側一穩定值，抑制了自頻移，而且孤子的各物理量最後都穩定在一穩定值，這些與nls孤子微擾理論都是類似的。有所不同的是，寬度為飛秒量級下， mnls孤子平均頻率的穩定值更接近初始平均頻率，更接近數值計算結果。This paper describes mainly system functions, measuring methods, circuit design, software program and errors analysis of a new type of measuring instrument. this instrument can measure and monitor electric parameters in single - phase circuits, three - phase ( three - wire or four - wire ) circuits. this system can be applied to electric devices and power plants, transformer substations with harmonic pollution. it can measure current, voltage, power, energy, frequence, power factor etc. it also can detect load quality, phase sequence, alarm, display and print results, as well as detect and dispose negative power
該儀器適用於含有諧波污染情況下的機電設備現場、發電廠、供電局、企業變電所現場，可用來測量電流、電壓、有功功率、無功功率、視在功率、有功電能、無功電能、視在電能以及頻率和功率因數等電參數，並具有負載性質（感性、容性）判別，正、逆相序判別指示功能；超限報警功能；列印記錄功能和負功檢測及處理功能。Analysis software. the analysis show : the gyroscope effect to the flywheel rotor ' s and the shaft ' s vibration character under high rotate speed should be considered. at this time, the system ' s normal frequency is the function of rotate speed ; the amplitude passing through the resonance field can be lowered obviously by improving the effective damping of the electro - magnetic bearing
建立了高速旋轉狀態下，採用磁軸承作支撐的飛輪轉子和轉軸的動力學模型，給出了有限元法在此問題中的具體應用，並利用i - deas有限元分析軟體具體分析了飛輪系統的共振頻率、系統振型，以及對偏心激勵的響應，分析表明：對于高速旋轉的飛輪轉子和轉軸，應考慮陀螺效應對其動力學特性的影響，此時系統的固有頻率是轉速的函數；通過提高磁軸承的等效阻尼可顯著降低系統通過共振區域時的振幅。The influence of msfvw bandwidth on the diffraction efficiency is also considered. for the nonuniform bias magnetic field of u - type parabola profile, when the msw frequency is less than the cut - off frequency at the edge of mo film, the effective mo interaction length reduces. the edge cut - off frequency is determined by the maximum of the nonuniform field
對于拋物型分佈（開口向上）的偏置磁場，當激發靜磁波的rf頻率小於邊緣截止頻率時，磁光作用的有效長度減小（與靜磁波頻率有關） ;邊緣截止頻率由不均勻磁場的最大值決定，靜磁波的下限截止頻率由不均勻場的最小值確定。Then, we establish the finite element analysis models of the antenna in different structure layout, and obtain the corresponding frequencies and model shapes. finally, according to the importance of each object, we set up the model of multiple objects that aims to maximize the first natural frequency and minimize the mass. combining orthogonal experiment and variant weighting coefficient method, we formed an effective multiple objects optimized algorithm basing on the neural network and genetic algorithm
本文首先詳細的敘述了天線結構的各組成單元，闡明了天線反射拋物面的形成原理；然後在ansys軟體環境中建立了不同結構布局下天線的有限元分析模型，分析計算了各種情況下天線的的固有頻率與振型；最後依據天線各指標的重要性，建立了以一階固有頻率最大、質量最小為目標的天線結構多目標優化設計模型，並基於神經網路和遺傳演算法，結合正交實驗和變加權系數技術，形成了一種有效的多目標優化演算法，在matlab平臺下實現了天線的結構多目標優化設計計算程序，求得了天線的最佳結構參數。First, the system operation conditions that include three input types ( square, sinuous and triangle ) with different frequencies ( l / 250hz, l / 5hz and 1hz ) are discussed. in fault detection processes, we construct 4 three - layer bp neural networks to learn the normal states of the system. the outputs of trained neural networks are as the estimate values of the sensors
本文詳細研究了在這種情況下的故障診斷問題，針對某液壓系統，分析了系統在方波輸入、正弦輸入、鋸齒波輸入下，分別在正常工作頻率、極限工作頻率以及接近極限工作頻率等9種工作狀態的特性，以及在這9種工作狀態下，運用神經網路觀測器進行傳感器故障診斷研究。The paper establishes mathematics model of electromagnetic heating system of eddy current field and temperature field, and gives corresponding discrete format with elements as eight nodes, hexahedron equal cell, through calculating eddy - current field to gain the internal heat source that the temperature field needed, to use discrete method to solve the problem of induction - heating part ' s temperature field by axial symmetrical electromagnetic, and then to analyze the characteristic of instantaneous temperature field
本文建立了電磁加熱系統的渦流場和溫度場間接耦合的數學模型，分析了不同頻率下渦流和溫度的分佈情況，並以八節點六面體等參元為例給出了渦流場對應的離散格式，通過計算渦流場獲得溫度場所需要的內熱源強度，加熱部件的溫度場以軸對稱格式進行離散求解，並對瞬態溫度場有限單元法的求解特點進行了分析。Simulations with respect to two models, prove that the method can track the frequency accurately and instantly, and have the preferable effectiveness on the abruptly fluctuating - frequency power signals, at the same time, this method overcomes the constraint of synchronous sampling and has the better astringency with different initial frequency
針對兩種模型進行模擬，表明該方法能夠較為精確與快速地跟蹤電網頻率，尤其針對突變頻率的信號，具有較好的跟蹤效果；同時演算法克服了同步采樣條件的限制，通過迭代，在不同初始頻率下均具有較好的收斂性。Focusing on a 64 - bit high - performance general purpose microprocessor with fully independent intellectual property, the thesis investigates a 128 - word 65 - bit general register file with 12 - read and 8 - write ports which is a representational one for its large - scale and multi - port characteristics in that microprocessor, and realizes its full custom design with high speed in read and write access. from the layout simulation result, under the 0. 18um process, the upper limit working frequency for the register file is 900mhz
本文面向一款具有完全自主知識產權的64位高性能通用處理器，對其中具有代表性的128字65位12讀埠和8寫埠的通用寄存器文件進行研究，實現了它的高速讀寫全定製設計，版圖模擬結果表明，在0 . 18um工藝下，設計可以工作的時鐘頻率上限為900mhz 。Taking the natural frequency arid the ratio of frequency drop as input characteristic parameters, crack damage in the cylindrical supporting shell of a portal crane is diagnosed and its length and position are forecasted, applying finite element emulation and artificial neural network technologies
摘要應用有限元模擬技術和人工神經網路模型，以反映結構損傷程度的固有頻率和損傷的頻率下降率作為神經網路輸入的特徵參數，對門座起重機筒形支柱上出現的裂紋損傷長度和位置進行了綜合診斷和預測分析。Then the general plan of underwater vibrators is put forward. in chapter 3, combining fluid - solid coupling theory and mechanical vibration theory, we get the coupling equation of moving parts and water. the dynamic characteristics of moving parts are studied with theory of finite element, and additional mass of moving parts is found in fluid - solid coupling field, which makes vibrator ' s natural frequency descend and amplitude - frequency curve downward shift
第三章運用流固耦合理論和機械振動學理論相結合的方法建立運動部件與水的耦合運動方程，利用有限元法對其的動態特性進行了研究，得到了在流固耦合場下運動部件存在的附加質量，該附加質量導致固有頻率下降，單位推力下的加速度頻響曲線整體下移。The liquefiable site was simplified as a double - degree - freedom model and the formula for calculating the reduction of horizontal natural frequency induced by liquefaction was attained
將可液化場地簡化為雙質點模型，給出了液化導致場地水平自振頻率下降的計算公式，推導出了頻率下降率的下限值。The transient analysis and simulation studies in time - domain showed that the transient capacitance current of busbar is unable to be caught due to the limitation of the given sampling frequency, therefore the transient current singularity of the fault line and the non - fault line will approximate, which prevents to identify the fault line with the criterion calculation result of transient current protection
研究結果表明，線路出口故障時暫態電流保護完全失去選擇性的根本原因是，在給定的采樣頻率的限制下，難以捕捉到過渡過程中極其短暫的母線分佈電容中的暫態電流，從而故障線路與非故障線路暫態電流波形的奇異性相近，根據故障線路和非故障線路的暫態保護判據計算結果不能正確識別故障線路。分享友人