降聲系數 的英文怎麼說
中文拼音 [jiàngshēngxìshǔ]
降聲系數
英文
noise reduction coefficient-
Based on the research of the characteristics of piezoelectric ceramic, this paper presents the analysis of the movement of the stator surface points and work principle of motor. this paper describes a theory about the influence of the ultrasonic vibration on the frictional properties of ultrosonic dring, and finds that the horizontal vibration produces friction driving force and vertical vibration affects horizontal driving effect
並且對行波型超聲波電動機的減摩現象進行了研究,發現在接觸區定子表面上一點的水平振動產生摩擦驅動力,垂直振動只起影響水平驅動效果的作用,得出垂直方向超聲振動具有減振作用是引起超聲驅動動摩擦系數降低的原因。The results are useful to further research on torsional vibration of the vehicle drivetrain, reducing the yawp of starting and ameliorating the capability of torsional vibration
為進一步分析車輛磨擦離合器接合階段傳動系的各個部分的參數對扭轉振動的影響、降低起步階段的噪聲、改進傳動系扭振性能具有一定的意義。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。Confirming 1072hz and 2193hz to be the most important control frequencies after the cohere analysis between vibration and noise signals. calculate the optimum parameters of two freedoms damping dynamic vibration absorber with the method of optimum parameter designing
計算鋼軌不同部位、不同方向的振動信號和噪聲信號的相干系數,得出振動信號和噪聲信號相干曲線圖,確定鋼軌減振降噪的主要控制頻率。The underwater - radio buoy for use as obtaining the ocean ' s acoustical parameters, applied for synthetic experimentations that seeing about ocean underwater acoustic environment, can obtain and memorize the data for all kind of underwater acoustic experimentations, for example, acoustic propagation, reverberation, ocean ' s noise etc. the system can not only reduce requires in quantity of using ships and scales in military strength equipment but also keep away from ships environments, reduce background noise and increase the quality of the gathered data
海洋環境參數獲取浮標監測系統用於海洋水聲環境綜合考察試驗中,獲取和記錄水聲傳播試驗數據。該系統不但可以減小參試艦船數量要求,降低兵力配備規模,而且可以遠離艦船環境,降低背景噪聲,提高所採集數據的質量。因此,浮標的研製對于保證未來海試完成既定試驗目標、順利完成試驗項目具有重要意義。Travel time is the key point of system, its measure quality decides the survey precision of the stress. time to digital convertor ( tdc ) was applied to accomplish the precision time interval measurement. at the same time, one transmitter - two receivers probe arrangement and zero - crossing detecting method were also applied to reduce the errors in measurement
傳播聲時是整個測量系統中的關鍵量,其測量水平決定應力的測量精度,對此本文採用時間-數字轉換器( timetodigitalconvertor , tdc )完成高精度時間間隔測量,在實現過程中又分別採用「單端發射-雙端接收」的探頭布局模式和「過零檢測」手段來降低系統檢測誤差。So, the emphases are put on this part. first, all sources of noise are analyzed and calculated to determine the parameter of component and estimate the feasibility of the system. second, on the one hand, low noise wideband and high gain amplifier is detailed particularly in the design of hardware, on the other hand, several mathematical methods are introduced to reduce the noise further in the design of software
首先,詳細分析了整個系統的噪聲來源,計算可能出現的噪聲,在器件的選擇上對參數提出要求,並分析方案的可行性;其次,在硬體設計上,兼顧帶寬,噪聲與放大倍數;在軟體設計上,採用累加平均,最小二乘擬合等信號處理方法,進一步降低噪聲。5 a multi - thread software cooperated with smp ( 2 cpu ) hardware performs the image - preprocessing correlation and post - processing synchronously, thus an automatic working module is realized. 6 systematic designed software, including grabing sarnies constructing rfl diging roi, and trainning ann offline and inline modules, has passed the practical tests which indicates that the opr could reach the recogniton possibility above 85 % and decrease the false alarm in the environment of high noise low contrast and multi - objects. and these are proved stable and repeatable in statistics, and so an advanced progress toward practical systems is achieved
6 、系統化設計的軟體,包括了樣本採集、參考濾波器庫構成、相關平面的roi採集,以及ann脫機訓練、 ann聯機運行的軟體功能模塊,在實時運行的測試結果中表明了該opr系統對處于高噪聲、低反差、多目標的惡劣條件下,對三維畸變目標的判識率( > 85 % ) ,降低了虛警率,並通過大量的實驗數據證明了該系統各項指標的穩定性和可重復性(從統計意義上講) ,向實用系統邁進了一大步。The equation of noise reduction due to the absorption will be deduced and added to the total noise reduction
探討屏障的吸聲性能對繞射降噪量的貢獻,並推導出與吸聲系數有關的繞射降噪量的公式。Secondly, ground on the duct noise control, the delayed - lms algorithm, which is actulized easily, is brought forward, then the simulation on pc is achieved. it is shown from the computer simulation that for the single frequency noise, there will be a good effect when choosing the suitable parameters ; but for the narrowband noise, the effect will become worse with increasement of the bandwidth. this result is helpful to analyze the parameters influencing anc
結果表明: ( 1 )隨著濾波器長度的增大,系統收斂速度變快; ( 2 )隨著值的增大,系統的收斂速度增大,但是當值超過某一范圍時會引起系統的發散; ( 3 )次級通路的延遲數與初級噪聲頻率有關; ( 4 )對于窄帶信號, dlms演算法可以取得一定的降噪量,但是隨著窄帶信號帶寬的增大,降噪效果明顯變差。The result shows that average absorption coefficient and noise reduction coefficient separately equal to 0. 58 and 0. 60, and fine property of sound absorption at middle - low frequency
結果表明材料的平均吸聲系數和降噪系數分別達0 . 58和0 . 60 ,且材料的中低頻吸聲性能優良。Researching on the technology if reverse order is to study strains if pits, structural systems if basement, environmental surwey and underpinnings. on account of emphasizing developing methods if checking strength if pick - ets, modemizing machenes of excavation and studying methods of underpinning is put forward and is a way if controlling the quality of pickets in sites, which leads an active effect ; synthetic application if rankintheory, spatial and time effect theory to excavation tl aanalyze the state of soil force and strain is brought forward and the time effect should be considered in the zone of clay, the formation and development of soil plasticity are analyzed and the most dangerous zone to decide how to excavate and where to begin is found ; analyzing the cause of picket settlement during reverse order and the differential settlement and discussing hlw to solute it. duringh the temporary survey and the environmental warship, bringing rorward the theory of environmental vibration and analyzing the state of soil force and probability of losing stabilization of soil under the effect of environmental vibration ; analyzing the state offeree in underground concrete wall by the method of mathematics and pointing out the place of the maximum force and deformation. based on systematic illustrating the reverse order, problems about application and development of reverse order and suggestions also are expressed
鑒于國內外的研究把重點放在大力發展工程樁的實驗室承載力監測方法與設備、如何使土方開挖機械現代化及對周圍建築的臨測方法上,本文提出了現場利用聲波層析成像技術監測鋼砼樁內部質量的方法與程序,並得出了聲波層析成像技術是砼樁的動態質量檢測的有效手段,這對指導施有積極、現實意義;提出了綜合運用朗肯土壓力理論、基坑空間和時間效應影響理論來分析逆作法施工過程中基坑邊坡土體應力及應變的變化情況,指出粘土地區也應考慮時間效應,並且進一步分析了基坑邊坡土體的塑性區形成和發展,找出邊坡最不利的區域,以確定地下室土體的挖掘的方式和順序,指出憑主觀臆斷與經驗來施工是不可取的;在分析、經較逆作法與大開挖順作法的地下室結構體系受力情況及施工順序的不同,提出了節點處理技術;分析了逆作法施工期間樁的沉降變化原因及由此而產生的差異,並探討了解決的方法;本文還提出了環境振動對土體邊坡穩定產生影響的觀點,並分析了在環境振動影響下,土體的應力狀態及土休失穩破壞概率,並且還運用彈性力學知識和數學分析的方法定量地分析了地下混凝土墻受力狀態,指出了被監測墻體的最大應力、應變位置。The total sound radiation power can be reduced by counteracting the adjoint coefficients of sound radiation modes of the first n radiation modes
聲輻射模態伴隨系數與對應的輻射聲功率成正比。通過抵消前n階聲輻射模態伴隨系數,就可以使總聲功率降低。The simulated results show that we can improve the sensitivity by setting the optical bias at / 2, reducing the gap of electrode, increasing the overlap integral factor, reducing the insert lose, adopting suitable segmentation number, increasing the electrode length, increasing the optical power, reducing the wavelength and the relative intensity noise and reducing the receive bandwidth ; obtain the wider bandwidth utilizing reducing the electrode length and the capacitance of modulator, segmentation the electrode ; increase the dynamic range using lowering noise, increasing the optical power at the detector and lower optical bias
通過計算得知,使傳感器相位偏置為/ 2 ,減小電極間距,提高電光重疊因子,減小器件插入損耗,採用合適的分段數,增加電極長度,增大光功率,降低激光的波長,減小相對強度噪聲,減小接收帶寬,對提高靈敏度的效果是非常明顯的。而減小天線長度,降低調制器電容,電極分段,都可以獲取較大的帶寬。降低系統噪聲;增加到達探測器的光功率,採用較低的光學偏置,都可以增大線性動態范圍。The established contact model has provided good explanation for the phenomena of the reduction of frictional coefficient induced by longitudinal ultrasonic vibration and has great academic significance in proposing friction reduction technology based on elliptical ultrasonic vibration
對該模型的分析很好地解釋了縱向超聲振動所引起的摩擦系數降低的現象,為提出利用橢圓軌跡超聲振動來實現減摩奠定了理論基礎。First, according to the orthonormal quality and the rational choice of working point of the sonar array three shafts frame, the structure of the models is predigested preliminarily ; secondly, according to the quality indexes and the coupling quality between frames, relatively small quantum is neglected. so the complex non - linear coupling models of the sonar array are predigested farther ; lastly, considering the characteristic of the model coefficient matrix, the methods of the low rank polynomial approach and the error simulation are introduced. so the models are predigested again
首先從聲納基陣框架結構的正交性和工作點的合理選擇出發,使模型的結構得以簡化;其次根據系統性能指標及框架間耦合性強弱,忽略相對小量,對聲納基陣復雜的非線性耦合模型進一步簡化;最後考慮模型系數矩陣的特點,運用低階多項式逼近和誤差模擬的方法,實現了對模型的再次降階簡化處理。This ku - band three channel receiver consists of spst modules, lna modules and image rejection mixer modules. these modules were designed and tested separately, then were assembled to the whole receiver. all the circuits were designed with small - sized devices so as to reduce the total size of the receiver. and the noise figure was considerably reduced because of the image rejection mixer
另外,由於採用了鏡像抑制混頻器,從而使整機噪聲系數大為降低。在設計方法上,本文採用了先進的微波電路設計軟體ansoftserenade對所有的電路和系統進行設計、優化和模擬,大大的縮短設計周期,提高設計效率。Therefore, wool dyeing at low temperature in short time is feasible from the view of technology and economics ; it has a bright feature in dyeing industry
結果表明,超聲波染色不僅可以提高染料的平衡上染百分率,節約能源和降低染色成本,而且還可以加快上染速率,增大擴散系數,降低染料上染的活化能。4. the lpfgs are used in single wavelength er - doped fiber amplifiers ( edfas ) as a spontaneous emission noise ( ase ) filter, and the gain of the edfa is increased by 7db and the noise figure ( nf ) is decreased by 0. 5db, for the first time
4 、成功研製了摻鉺光纖放大器,首次將高頻co2激光脈沖寫入的長周期光纖光柵應用到摻鉺光纖放大器中作為自發輻射噪聲濾波器,使edfa的增益提高了7db 、噪聲系數降低了0 . 5db 。The proposed algorithm lows the complexity by choosing decision delay in advance and then making solution of the equalizer tap coefficient, a new decision delay choice method is proposed, solution by using weight method, diagonal matrix transform, z extension and a new energy restrictive condition which restrains noise enhance, a new decision delay choice method is proposed, the simulation result shows that the proposed algorithm has better equalization effect and enhanced performance comparing to the general mmse algorithm, simulation research on the precision and dynamic scope of parameters in digital realization time domain equalization algorithm, design software and hardware of time domain equalizer. fourthly, there exist a lot of interfere in dsl line, especially, dsl works in multi - user mode, the near end interference is serious
通過先選擇判決時延,再進行時域均衡器抽頭系數求解的方法降低了時域均衡計算復雜度;對于均衡器抽頭系數的求解使用了加權技術,通過對角矩陣變換, z擴展,使用不同的能量約束條件對演算法求解,結果表明這種約束有效的抑制了噪聲增強,與常用刪se比較,該演算法有更佳的均衡效果,演算法性能得到了提高:論文還對數字化實現時域均衡演算法中每一部分參數的精度、變量的動態范圍進行了模擬研究,對時域均衡的軟硬體實現進行了設計。分享友人