最大頻率 的英文怎麼說
中文拼音 [zuìdàbīnlǜ]
最大頻率
英文
maximum frequency-
And then facing the problem of the channel estimation of the adaptive modulation system, we conclude out the channel estimation algorithms on maximum likelihood ( ml ) estimation and maximum a posteriori ( map ) estimation under the condition of flat fading channel and selective fading channel in detail. to meet flat fading channel, we simulate the relationship of the ratio between the error covariance in map estimation and ml estimation and pilot symbol message length. the conclusion can be drawn from these results
接著,對自適應調制系統中的通道估計問題難點,詳細推導了平衰落通道條件下和選擇性衰落通道條件下最大似然( ml )估計和最大后驗概率( map )估計演算法,針對平衰落通道,我們模擬了map估計和ml估計的方差與導頻符號長度的關系,模擬結果表明,錯誤方差受多譜勒頻率的變化影響最大,並且對實際的自適應調制系統,導頻符號長度的取值超過20個符號長度時, map通道估計明顯優于ml通道估計。The thermal damping is maximum for frequencies corresponding to pulsations that are somewhere between isothermal and adiabatic.
當脈動處于等溫和絕熱之間某個狀態時,相應頻率下的熱阻尼是最大的。( 2 ) gene flow frequency was reduced as distance from pollen donor increased and a dramatic reduction occurred at about 2 meters. the maximum distance where gene flow was not detected was 50 m for hybrid rice while it was 70 m for ms lines, with an exception that in one of the four ms lines it was detected a frequency of gene flow 2. 8 + 10 - 6 at 150 m for zhong 9a
在開花期主流風向ne的風速為0 . 2 ? 2 . 2m / sec的條件下, 2個雜交稻品種的最大漂流距離為40m ; 4個不育系的基因漂流基本上到60m為止, 70m處基因漂流頻率均降為0 ,僅中9a在150m處發現了1株basta抗性苗,經pcr檢測驗證為陽性。We acquired the system ' s dynamic response when the satellite attitude was adjusted and the mode of the antenna. then modal analysis and dynamic analysis have been done to the satellite - antenna system by using the finite element analysis ( fea ) software of ansys. through the analysis we got the system ' s connatural characteristic, the amplitude - frequency characteristic of harmonic response, the power spectrum density of random vibration response, the maximal amplitude and resuming time of impact response
其次藉助ansys有限元分析軟體,對系統進行了模態分析和動力學響應分析,獲得了不同天線結構參數下的衛星?天線系統的固有特性,簡諧響應的幅頻特性,隨機振動響應的功率譜密度,以及沖擊響應的最大幅值和恢復時間等。A building of high, the breadth, long comparison is very important. house for combination in an ideal of big set, reruns hour then contain the best frequency to respond to the width. frequency response range in other words, the combination can broadcast tallest to can also fully develop to the lowest frequency, and the equilibrium degree is as well high, and halt a circumstance is very tiny. the first glint wave primary reflection mutual interference for with wave secondary reflection of many glints the degree is not to result in confusion. combination that fundermental the diapason wave harmonics is again perfect
大套組合在一間理想的房子里,重播時便有最佳的頻率響應寬度frequency response range 。換句話說,組合所能播放的最高至最低頻率也可以盡情發揮,平衡度亦高,駐波情況極微。第一反射音波primary reflection和多次反射音波secondary reflection的互相干擾情度不至造成混亂。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。Even under the condition that the filling pressure was up to 1. 5mpa, the onset temperature was only 237 ?. with the filling nitrogen of 0. 9 mpa, the maximal pressure ratio reaches 1. 21 and the operation frequency is 25 hz. the ratio of the harmonic wave of the engine was very little and the frequency jumping was not found in present experiments
在充氣壓力為0 . 9mpa的條件下,該熱聲發動機最大壓比可達1 . 21 ,遠高於駐波型熱聲發動機,實驗結果和理論分析均表明系統的工作頻率為25hz左右,實驗裝置的諧波比例非常小,且也沒發現頻率跳變等現象。By making some assumptions, collision frequency were presented. then the the flocculation kinetics model was established through population balance equation. comparison of experimental data and modeling results indicate that there are the same trend between the two. so the model can predict floes number and size during flocculation of yellow river ' s loess particles without using empirical parameters. the tem and sem were used to obsever floes in the study of floe structure. the flocculation was divided as flocculi, floc and floe aggregate. the floes structure model was established by assumption that particles position in floe accords with tetrahedron. the fractal dimension of model and experimental floes was found to be coincidentso the model can reflect the structure of flocs formed in flocculation of yellow river ' s loess particles by macromolecule flocculant at a certain extent
最後,本文還對絮凝動力學和絮體結構進行了研究,在前人研究的基礎上,針對高分子絮凝黃河泥沙,對絮凝過程作了一些符合試驗條件的假設,建立了顆粒碰撞頻率表達式,應用了顆粒數量平衡方程,從而建立了絮凝過程的動力學生長模型,模型計算結果與試驗數據對比表明,二者趨勢一致,在沒有使用經驗參數的情況下基本上能夠描述黃河泥沙絮凝過程中絮體數量和尺寸分佈的變化過程;對絮體結構的研究中,應用掃描電子顯微鏡和透射電子顯微鏡對絮體進行了觀察,將絮體分為絮粒、絮團和絮網三個不同的生長階段,通過假設顆粒結合位置符西安建築科技大學博士學位論文合正四面體,建立了絮體結構模型,計算得到的模型絮體分形維數基本與試驗中的實際絮體相符,在一定程度上能夠反映高分子絮凝黃河泥沙生成的絮體結構。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。The modulation of sound properties over a wide range of time scales is one of the most obvious characters of oscine passerine ' s vocal, whose song contains many different kinds of syllables that consist of many more multiple song phrases. in oscine passerine, ipsilateral projections of ra to nxiits innervates the ipsilateral syringeal muscles exactly, and thus they have strong ability of vocal control with variable tones, high frequency and higher lever of quality. as a result, the songs sound well
鳴禽鳴囀的最大特點之一便是其單次鳴唱時間長,鳴唱所包含的音節數量和音節種類繁多,因而由這些音節所組成的句型結構也是復雜多樣富於變化,且由於nxiits嚴格的側別控制(每一側核團只支配同側鳴肌) ,使其具有更強的控聲能力,其鳴聲音調變化幅度大,頻率高,品質因數大,音色好,因而其鳴聲也悅耳動聽。The test proves that the caudal fin oscillation frequency, the maximum amplitude of vibration of caudal fin, the caudal fin strikes the water angle influence the fish ’ s speed ; the curve experiment has obtained curve radius of inertia advance curve and static curve ; the ups and downs experiment proves that the pectoral fin on different angle influences the fish to move ups and downs
加減速試驗論證了尾鰭擺動頻率、尾鰭后緣最大擺幅以及尾鰭的最大擊水角度對魚體速度的影響;轉彎試驗測得了機器魚慣性前進轉彎和靜止轉彎時的轉彎半徑;在機器魚的升潛試驗中論證了胸鰭不同轉角對升潛運動的影響。In attempt to directly compare the sound response characters of the same bf neurons or different bf neurons and their interactive relation, the double recording microelectrodes were penetrated into two different neurons in iso - frequnency laminas or hetero - frequency laminas. taking advantage of frequency tonotopical arrangement in 1c of bats, it was explored how the neurons integrated different parallel processes of the same sound information. in the case of which, we hoped to explore the relation between the sound response characters of the central auditory neurons and neural modulation in background noise for the further understanding of the mechanism in the central auditory neurons extracting sound signals
本研究以大棕蝠( bigbrownbat , eptesicusfuscus )為模型,利用ic聲調組構排列成同頻層這一結構特點,突破單電極記錄和檢測神經元的方法,同時推進兩單電極至一個同頻層或兩個同頻層的兩個不同神經元,試圖從細胞水平直接比較兩個具有相同和不同最佳頻率的神經元聲信號的加工處理特徵、以及它們之間的相互關系,以期窺探它們在對同一聲信號處理過程中的整合奧秘,並以此為基礎分析和探討背景噪聲條件下中樞神經元聲反應特徵與神經調制的關系,以期進一步了解中樞聽神經元聲信號提取的機制。This study showed that the mt and sharpness of frequency tuning curves increased as the sound direction changed from contralateral to ipsilateral azimuthal angles. it suggests that sound direction effect on frequency tuning may be through the complex interplay between the excitatory and inhibitory inputs. the application of gaba ( a ) antagonist, bicuculline, lowered all mts but the application did not abolish direction - dependent variation in mt
聽皮層的抑制性影響使大多數神經元在蝙蝠最敏感的聲源方位c - 40的頻率分辨能力明顯提高,同時使c - 40和i - 40的最低閾值的差別進一步增大,提高了信噪比,提高下丘聽神經元對聲源方位和最佳頻率的分辨能力。22 paired inferior collicular neurons were obtained in the experiment. the neurons were recorded in the depth of 198 - 1254 u m ( 544. 59 ? 72. 37 n m, m + sd ), and their bfs were 11. 25 - 59. 29 khz ( 26. 77 + 9. 95 khz, m ? d ) : the minimum thresholds ( mts ) werelo - 66 db spl ( 38. 14 ? 14. 39 khz, m + sd ) ; the latencies were 4. 0 - 16. 0 ms ( 8. 19 + 3. 14 ms, m + sd ) ; the best intervals between paired sound pulses were 0. 01 - 28. 71 ms ( 3. 93 + 2. 52 ms, m ? d ) 0 the results showed : l ) there were interactions between the neurons in the iso - frequency lamina and hetero - frequency lamina which included mutual inhibition ( 18 / 22, 81. 8 % ) and mutual facilitation ( 4 / 22, 18. 2 % ), and the mutual inhibition in iso - frequency lamina was stronger than that in hetero - frequency lamina ; 2 ) the mutual inhibition decreased with sound level increasing ( p < 0. 001, anova ) ; 3 ) the analysis of the inhibition of discharge rate at lodb above mt showed that the inhibition increased when the paired neurons " bfs difference decreased ( r = - 0. 545, p = 0. 0006 ) ; 4 ) the mutual inhibition of paired neurons can sharpen the frequency tuning and the effect increased when the frequency was away from the bf ; 5 ) the changes in q10, q30 decreased with bfs difference of the paired neurons increasing ; 6 ) the mutual facilitation between paired neurons not only increased discharge rate, but also widened the frequency tuning, i. e., increased response frequency
結果表明: 1 )同頻層神經元之間或者非同頻層之間神經元之間存在相互作用,這種作用既有相互抑制( 18對,佔81 . 8 ) ,也有相互易化( 4對,佔18 . 2 ) ,且同頻層神經元之間的相互抑制作用較非同頻層神經元之間的相互抑制作用要強; 2 )神經元對低刺激強度反應時,所受到的相互抑制作用較強,隨著聲刺激強度加大,抑制作用逐步降低( p 0 . 001 , anova ) ; 3 )對閾上10db放電率抑制百分比進行的分析顯示,配對神經元之間的最佳頻率差越小,相互抑制作用越強( r = - 0 . 545 , p = 0 . 0006 ) ; 4 )配對神經元之間通過相互抑制作用可表kx碩士學位論文waiaster 』 sthesis現出調諧銳化作用,該作用的效率與頻率有關, bf處的銳化作用較低,偏離bf時其銳化作用逐步加強; 5 )頻率銳化作用的效率與bf差有關,隨著配對神經元之間的bf差擴亢q10 , q30值的變化逐漸減小,其變化百分比與配對神經元之間的頻率差存在明顯相關; 6 )配對神經元之間的相互易化作用不僅表現在放電率增加上,也表現在頻率調諧曲線的擴寬,即頻率響應范圍擴大。Connectors with assessed quality, for use in d. c., low - frequency analogue and in digital high speed data applications - rectangular connectors - detail specification for 8 - way, shielded free and fixed connectors for data transmissions with frequencies up to 600 mhz minimum
直流低頻率模擬及數字高速數據系統用的已進行過質量評定的連接器.矩形連接器.最低頻率為不大於600mhz的數據傳輸用8道無屏蔽固定連接器的詳細規范In the simulation experiment, the whole system model is founded by the software matlab / simulink. using the stator active power computed from the maximal output power of the wind turbine as the reference value of vector control system, the result of experiment approves that the control strategy is true. not only the frequency of stator current is constant, but the control of stator active and reactive are decoupled, and the output power tracks the maximal power of wind turbine
在最後的模擬實驗中,本文利用matlab軟體建立了系統各部分的模擬模型,選用與風力機最大輸出功率對應的定子有功功率作為矢量控制的參考值做了模擬實驗,並給出了模擬結果,驗證了定子磁鏈定向矢量控制策略的正確性:既保證了定子輸出頻率的恆定,又達到了有功功率無功功率獨立解耦控制的目的,同時還較好地跟蹤了風力機的最大功率輸出。Maximum frequency operation
最大頻率操作7 8 connectors for electronic equipment - part 7 - 7 : detail specification for 8 - way, shielded, free and fixed connectors, for data transmission with frequencies up to 600 mhz category 7, shielded
電子設備用連接器.第7 - 7部分:有最大頻率為600mhz的Secondly, basing on the theory of on - off gain of small signal, the raman gain coefficient for frequency shift between 0. 5 and 20 thz of standard sigle mode optical fiber is measured by pump - probe method through a super luminescent diode ( sld ) as a broadband small signal probe source. thirdly, numerical simulation analysis of gain characteristic of raman fiber amplifier for c band wdm signal light is made according to the raman gain coefficient of the fiber measured before through target and four rank runge - kutta method. at the invariability of wavelength and maximum power of each of two pumps, schematic of powers of two pumps for best flatness on c band wdm optical gain was found out, at the same time, the factors of resulting in gain saturation is analyzed, too
本文首先應用經典的電磁理論對拉曼光纖放大器的工作機制進行了分析,然後,根據小信號理論推導出的開關增益求出了光纖拉曼增益系數的表達式,採用泵浦-探測波的方法,利用超輻射激光二極體( superluminescentdiode簡稱sld )作為探測光源,測量了所用標準單模光纖頻移為0 . 5 - 20thz的拉曼增益系數,之後根據所測得的光纖的拉曼增益系數譜對應用該類光纖構成的放大c波段wdm光信號的拉曼光纖放大器的增益特性採用打靶法和四階龍格- - -庫塔進行了數值計算,在給定了兩個泵浦光源的波長和最大功率后,找出了反向泵浦情況下使c波段wdm光源增益最平坦的兩個泵浦的各自最佳功率,同時也分析了導致信號光飽和的原因。First, variable speed constant frequency wind energy convertion theory is described in this paper, then presents a review on the development of wind turbines control and the main types of generator and static converters used to interface variable speed wind turbines to the electric grid. then discuss main circuit constructure and advantage of direct drive wind energy conversion system and introduce pitch - control method for wind power traction and electric power stability. simply aerodynamic characteristic of the turbine is analysised and permanent magnet synchnonous generator math model is established. to convert the variable frequency electricity into utility grid, back to back four - quadrant pwm - vsi is used and three typies of control strategy is presented to capture the maximum wind energy and transmit energy. then simulation is implemented to test the control strategy. in the following chapter a simple ac - dc - ac converter with a dc - dc boosting chopper is proposed to transmit the wind energy into electricity energy and two control strategy is presented
建立了永磁電機和變流器的數學模型,針對雙pwm變頻器的特點提出了三種控制策略對變流器進行控制,通過變流器交-直-交的變換,將發電機發出的變頻變幅值交流電轉化為可用的恆定頻率的交流電,通過pwm調治能使其輸出功率因數為一,並且該控制系統功率因數為可調,能在特殊情況下同電網交換一定的無功功率,並通過對變流器的控制實現了最大風能俘獲的功能。最後採用matlab / simulink進行了模擬,取得了良好的模擬效果。在風力發電系統中,採用先進的最大功率俘獲演算法,能有效的從風中獲得最大的能量。分享友人