噪聲源系數 的英文怎麼說
中文拼音 [zàoshēngyuánxìshǔ]
噪聲源系數
英文
noise source coefficient-
This thesis was divided into eight chapters, and the main results and innovations obtained here can be summarized as follows : ( 1 ) the physics model of tsrs in frequency conversion crystals has been built up firstly. based on quantum - mechanical viewpoints and the following physical processes and parameters : the two - photo interaction of light with matter, paraxial diffraction of stokes, langevin noise sources, reflection at the faces and the edges of crystals, gain coefficient, beam aperture, pulse width and fluence of 3, the physics model of tsrs in kdp and kdp crystals acting as high - fluence frequency convector and the paraxial operator maxwell - bloch - langevin equations have been built up
全文共分八章,取得的主要成果及創新點如下: ( 1 )首次建立了諧波轉換晶體的tsrs物理模型本文根據量子力學原理,在考慮如下物理過程和參量的基礎上:光與物質的雙光子相互作用; stokes光的傍軸衍射; langevin (郎茲萬)噪聲源;晶體表面反射和端面反射;增益系數、光束口徑、脈寬和三倍頻光能量密度,推導出高通量激光在kdp和kd ~ * p諧波轉換晶體中的tsrs物理模型和空間上的近軸算符maxwell - bloch - langevin方程組。The circuit is used in high resolution resistance measuring. the coupled chaotic circuit array composed of this circuit is researched by computer simulation and circuit experiment. results show that, it is feasible to improve the stability of orders of chaotic systems and reduce noise in measuring by coupling
最後,對以這種單電源驅動的混沌電路為基本單元所構成的耦合混沌陣列在提高系統輸出的穩定性和抑制噪聲作用方面,進行了計算機模擬研究和實際的電路實驗研究,結果顯示通過耦合的方式,可以將信號檢測的精度提高近一個數量級。On the basis of increasing the flaw resolution of the x - ray radiographic system, the study is firstly concerned with the analysis made on the influence of such factors as redial sources energy, system noise, optics radiography and scattering on the radiographic system in theory, and the present dissertation looks at the methods for acquiring the radiographic system point sp read function, line spread function and module transfer function ( mtf ). on the basis of these studies, research the spread properties of the tiny flaw making use of mtf, acquiring the properties of system inspecting sensitivity and resolution, based on the system optimization designing
本文以提高射線成像系統的疵病解析度為前提,首先在理論上對射線源能量、系統噪聲、光學成像、散射等各環節對成像系統的影響進行分析,探討成像系統的點擴展函數、線擴展函數及其調制傳遞函數( moduletransferfunction ,簡稱mtf )獲取方法,在此基礎上,利用mtf研究微小疵病的擴展特點,從而得到系統的檢測靈敏度和解析度給出關系特性,為系統優化設計提供依據。During this precess, using the technology of optimizing the widths of both common source mosfet and common gate mosfet under a fixed power, we obtained a compromised result of power consumption and noise figure
設計過程中,在限定功耗的前提下,主要針對共源晶體管和共柵晶體管的柵寬,對電路的性能進行了優化,使得設計的lna的噪聲系數最小。This paper raised a new way for overlapping speech segregation based on sound localization cues. in this paper, we first divide the speech stream into some time - frequency regions and calculate the itd and iid of each region. then the notion of a " time - frequency " binary mask is given, which selects the target if it is stronger than the interference in a local time - frequency region
然後求取每個小片段上的itd (到達雙耳時間上的差異性)和iid (到達雙耳強度上的差異性)值,經過實驗證明某個片段上的itd值和iid值與該片段上的信噪能量比是單調遞增關系,因此通過和域值的比較,得出掩蔽系數,來判斷每個小片段具體是屬于哪個聲源。Abstract : on the basis of the analysis about noise sources of the air compressor, it shows that air dynamic noise is primary one. according to the theory of fluid mechanics, the mathematics model of the air compreesor air dynamic noise is found, which shows the relationship between the sound power level and other parameters. the knowing noise of the air compressor " s air dynamic is of low frequencies. the reliable data is provided for the noise and vibration control
文摘:通過對空壓機噪聲源的分析,確認空壓機噪聲源中的空氣動力性噪聲為最強;由流體流場的聲學理論,建立空壓機動力性噪聲源的力學模型,它表明聲功率與其它參數的關系;並知空壓機的空氣動力性噪聲呈低頻特性,這為噪聲及振動控制提供了可靠的依據The sensitivity to the initial value of chaos system makes it easy to produce a lot of sequences, which can be the source of the digital noise
混沌系統對初始值的極端敏感又使得由它產生的序列量眾多,從而成為數字噪聲取之不竭的源泉。Therefore, this paper studies three kindsvalves such like bufferfly valve, brake valve and ball valve, with the numerical simulation method by cfx which is often used to simulate the fluid. by the simulation of three kinds of valves, we can kown dynamic characteristic of them. in this paper, i not only simulate for three kinds of valves, but also analyse cause of flow - noise and give respectively mathematical model of main noise sources in piping system such as pupm and valve
本文通過cfx軟體,用數值模擬的方法,對海水管路系統中常見的三種閥門(蝶閥、閘閥、球閥)流動特性及噪聲進行了模擬分析,闡明閥門噪聲產生的機理,建立了泵和閥門等噪聲源的數學模型,並對管路系統中涉及到的邊界條件做了適當的處理,分析了閥門下游的渦聲。In the hardware implementation of a multi - channel active noise control system, the computational complexity is increased sharply when the number of filter coefficients and channels are increased
摘要在多通道有源噪聲控制系統的硬體實現中,當通道數目增大或濾波器長度較長時,常規的多通道演算法運算量急劇增加,使控制器可能無法實時實現。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。In the thesis the low drag - low noise optimization of the vehicle main form design is realized, main accomplishments are as follows. researched the knowledge of drag and flow noise, the parameters of the boundary layer are calculated by the hess - smith method and boundary layer momentum integral method. the calculation of the length of transition zone and change in boundary layer displacement thickness between laminar and turbulent states in the transition is improved, then the drag coefficient and self - noise from the transition zone are calculated as the objective functions of the optimization
主要研究內容和成果如下:對航行器繞流流場進行分析,深入研究了阻力和流噪聲產生機理,建立了阻力系數和自噪聲的評估數值計算模型;採用物面分佈源匯法和邊界層動量積分法對繞流流場的流體動力參數進行計算,改進了轉捩區長度和邊界層位移厚度的計算,應用於航行器頭部駐點自噪聲的計算;最後設計了阻力系數和自噪聲數值計算程序模塊。Taking the ffc ? 23a disk mill as a specimen model, the rotation noise generated from the interaction between fixed claws distributed on the outer and inner circle of the fixed claw plate and the corresponding moving claws has been separated in an experimental study by the modern analytic method of acoustic. thereby, a conclusion that the principal component of rotation noise in disk mill comes from the interaction between the fixed claws on the outer circle and the corresponding moving claws has been reached. in accordance with the above, modified noise reduction design for the structural parameters such as the number of claws on the fixed claw plate, shape of claws and the relative positions of the claws arranged on the outer circle and inner circle has been carried out
本文以ffc ? 23a型爪式粉碎機為樣機,利用現代聲學測試分析手段對其工作時定齒盤內、外圈齒與相應動齒作用產生的旋轉噪聲進行了試驗分離研究,從而得出了爪式粉碎機旋轉噪聲的主要成分源自外圈定齒與其相互作用的動齒產生的噪聲,並以此為基礎,對定齒盤的齒數、齒形以及內、外圈齒的相對排列位置等結構參數進行了降噪改進設計,通過對比性試驗與分析,獲得了旋轉噪聲與上述結構參數間的關系,並取得了負載6 . 7db ( a )的良好降噪效果。Entropy preservation is considered of the tempest transceiving system. anti - noise performance of the digital interception is also taken into account by both theory and experiment electromagnetic information leakage and its protection & interception technology are studied theoretically and experimentally in this dissertation
建立了泄漏發射源和偵收系統的信息論模型,討論了tempest收發系統的保熵性,從理論和實驗兩方面開展了數字偵收系統的抗噪聲性能研究。A new aerodynamic design system developed by authors for draft fan with enhanced efficiency, suppressed noise, enlarged flux and high load. the new design system features : a twist regulation for vortex control is employed in designing to lessen the secondary flow loss in the blade tip and hub ; the feasibility and high efficiency of this procedure has been verified by the tests of the prototype fan ; a new computer - aided 3d blading is used to optimize the blade ; numerical inverse checking is adopted to enhance accuracy in designing and cut down the period of the designing and production. this design system can make the optimized blade with " forward inclination ", " inclining sweep ", " bending sweep ", to minimize the various secondary flow losses, to expand the steady working range of the fan, and to suppress the aerodynamic noise source
本文通過對一種新型高性能礦用局部通風機的設計、製造及試驗全過程的綜述,展現了新的先進設計體系在民用通風機上的成功運用,其研製特點是: ( 1 )在葉片氣動設計中為了降低葉根及葉尖區二次流損失,採用可控渦扭向規律設計,樣機實測的高性能驗證了這種方法的可行性和高效性; ( 2 )在設計方法中採用較精確的數值反驗算,獲取最優設計方案,大大提高設計的準確性和成功率,並縮短了設計試制周期; ( 3 )在設計過程中發展了計算機輔助三維葉片造型新方法,可以根據設計需要簡便快捷地對葉片進行「前傾」 、 「傾掠」或「彎掠」造型,這些造型對減小各種二次流損失、擴大穩定工況范圍和控制葉輪機氣動噪聲源起到了非常好的作用。Abstract : a new aerodynamic design system developed by authors for draft fan with enhanced efficiency, suppressed noise, enlarged flux and high load. the new design system features : a twist regulation for vortex control is employed in designing to lessen the secondary flow loss in the blade tip and hub ; the feasibility and high efficiency of this procedure has been verified by the tests of the prototype fan ; a new computer - aided 3d blading is used to optimize the blade ; numerical inverse checking is adopted to enhance accuracy in designing and cut down the period of the designing and production. this design system can make the optimized blade with " forward inclination ", " inclining sweep ", " bending sweep ", to minimize the various secondary flow losses, to expand the steady working range of the fan, and to suppress the aerodynamic noise source
文摘:本文通過對一種新型高性能礦用局部通風機的設計、製造及試驗全過程的綜述,展現了新的先進設計體系在民用通風機上的成功運用,其研製特點是: ( 1 )在葉片氣動設計中為了降低葉根及葉尖區二次流損失,採用可控渦扭向規律設計,樣機實測的高性能驗證了這種方法的可行性和高效性; ( 2 )在設計方法中採用較精確的數值反驗算,獲取最優設計方案,大大提高設計的準確性和成功率,並縮短了設計試制周期; ( 3 )在設計過程中發展了計算機輔助三維葉片造型新方法,可以根據設計需要簡便快捷地對葉片進行「前傾」 、 「傾掠」或「彎掠」造型,這些造型對減小各種二次流損失、擴大穩定工況范圍和控制葉輪機氣動噪聲源起到了非常好的作用。Abstract : a noise model for the analog correlator used in the ultra wideband receivers is proposed due to lack of simulation capability on noise performance of the correlator in current eda tools. the analog correlator circuit is divided into several parts to calculate the equivalent noise sources respectively. the ideal impulse generators, instead of the noise sources, are then applied to obtain the time varying transfer functions. fourier transforms are carried out to explore the relationship between the noise input and output in frequency domain for each part. then the symmetrical noise sources are grouped together and the periodicity of the circuit is utilized to further simplify the model. this model can be used to evaluate noise performance of the correlator
文摘:給出了分析模擬相關器的噪聲模型.將相關器分成不同的幾個子模塊后,對各模塊分別計算等效噪聲源.然後用理想脈沖源代替噪聲源計算電路的時變傳輸函數,接著用傅里葉變換計算輸入輸出的頻域關系.利用電路的對稱結構合併對稱的子模塊可以進一步簡化模型.該模型可以用來估計相關器的噪聲性能Based on these conditions, this thesis describes the methods for the blind source separation of noisy harmonic signals from rotating machine when the underlying system is underdetermined ( i. e. separation of n sources from m mixtures, when m < n )
本論文主要以「滾動軸承-轉子」系統為對象,研究存在噪聲情況下,當測試傳感器的數量少於信號源的數量(欠確定)時,旋轉機械振動信號的盲源分離問題。It is shown in mechanism analysis that 1 / f noise originating from border traps is ~ sensitive to both of the oxide charges and interface traps induced by esd and hci and the similarity coefficient can express the local characterization more thoroughly, while the changes of electrical parameters usually lie on one of the defects
機理分析表明,起源於邊界陷阱的1 / f噪聲對于靜電和熱載流子誘發的氧化層電荷和界面陷阱兩類缺陷都同時敏感,而相似系數更能反映1 / f信號的局域特性,但電參數的變化通常主要取決于其中一類缺陷。After a great amount of detailed computer simulations and concise qualitative and quantitative theoretical analysis, the turbo codes " parameters and fpga specific hardware implementation architecture suitable for being integrated into dtv systems are determined. furthermore, the codec is completely designed with verilog hdl, ending with an occupation of less than a 600 - thousand - gate fpga chip. at this lowest hardware cost, a white noise snr threshold of 1. 8db at a net stream rate of 6mbps is achieved, which exceeds all other existent dtv systems " performance
經過大量詳細的計算機軟體模擬和簡明扼要的定性與定量的理論分析,最終確定了數字電視系統中適合採用的turbo碼參數及針對fpga特殊構架的硬體實現結構,並用verilog硬體描述語言完成了turbo碼編譯碼器的完整設計,以佔用不到一片60萬門fpga晶元的較少的硬體資源取得了在6mbps凈碼率下1 . 8db的白噪聲信噪比門限這一遠遠超過現有任何數字電視系統的性能。Reverberation room is the special test room that is used in acoustics, in the measurement of sound absorption coefficient in random incidence and determination of sound power levels of noise sources, the reverberation room is used very extensively
摘要混響室是聲學專業的實驗室用房,它在測量聲波無規入射時材料的吸聲系數和測量噪聲源的聲功率級中得到了廣泛應用。分享友人