噪聲指數計 的英文怎麼說
中文拼音 [zàoshēngzhǐshǔjì]
噪聲指數計
英文
noise figure meter-
Abstract : this paper describes the classical mathematic model of bolometer, the effect of thermal isolation and noise on detector performance are also discussed
文摘:總結了非製冷測輻射熱計的經典數學模型，並分析了探測器熱絕緣結構和噪聲對性能的影響，指出了性能改進和優化的基本途徑。An under estimation of the hearing effects by the low frequency noise could be happened. that is to say, even if the a - weight sound level is small, the low frequency noise may annoy to listener by the different ways from the high frequency noise. so it is necessary to understand psychoacoustics in order to make noise quality evaluations that match the subjective experience of the purchaser
同時應用主觀評價方法?成對比較法（ paircomparisonstatisticalevaluationmethods ）對不同家用空調器噪聲進行主觀評價試驗，並與客觀評價結果進行了對比，結果表明：人主觀響應（煩躁程度）與各心理聲學評價指標之間均具有很高的相關性，相關系數一般均大於0 . 9 ，而與a計權聲壓級之間的相關系數只有0 . 78 。Firstly it discusses the value, meaning, background and method of this topic. then it deducts the single - bubble sound pressure, spectrum of sound pressure, power spectrum. according to the real situation of traveling bubble cavitation noise around a schiebe body, the mathematical model of single - bubble collapse is selected, furthermore, the mathematical model of mass traveling bubbles without interference effect is established, and the multi - peaks and rebound phenomenon while bubbles collapse is also analyzed with statistical method
首先論證了本項研究的意義，價值，背景和方法，然後推出了單空泡輻射噪聲聲壓，聲壓譜和功率譜，針對回轉體流動泡空化噪聲的具體情況，選擇了雙指數模型作為單空泡潰滅的數學模型，進一步建立了無干涉條件下的群泡輻射噪聲的數學模型，並用統計的方法分析了空泡潰滅時的多峰值和反彈現象。Experimental results show that wls is better than classical autoregressive ( ar ) models for 0. 5 < h < 1. it also can be seen that the disadvantage of wls is most salient for the lower of estimate accuracy of hurst exponent
本文對wls法進行了模擬研究，研究結果表明wls法對h 0 . 5的1 f噪聲的濾除作用明顯優于傳統的ar模型，但同時發現wls法對hurst指數的估計誤差較大。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。Time delay was chosen by using autocorrelation function method and mutual information method, while reconstruct dimension was obtained by g - p saturation correlation dimension method and false nearest neighbor percentage method. furthermore, initial neighborhood radius was computed by the estimated noise level based on the g - p saturation correlation dimension method. secondly, a noise reduction of the inflow time series was carried out by chaotic nonlinear local projection noise reduction method, and the effects on noise to chaotic characteristics and state reconstruction parameters were discussed
採用g - p關聯維法計算關聯維數； rosenstein法和kantz法計算最大lyapunov指數；重構相空間的延遲時間採用了自相關函數法和互信息量法；嵌入維數採用了飽和關聯維法和偽鄰近點法；初始領域半徑的選取採用了基於g - p關聯維法的噪聲水平的初始估計方法。Fortunately, we can solve this problem by using ap ( alternating projection ) algorithm, by this way ; the computational load can reduce dramatically. doa estimation is mostly research base on linear array, because of the limitation of linear, it can estimate the azimuth only ; solid array can estimate the azimuth and elevation, in this paper, the solid array is used for doa estimation ; when the signal sources are uncorrelated, the music algorithm is chosen, using mdl / aic algorithm, we attain the signal number of sources
本文採用立體六元陣進行測向，在非相干信號源條件下，採用music演算法進行doa估計，採用基於信息論原理mdl準則或者aic準則判斷信號源數目，通過對陣列流形的研究，指出基於圓陣的陣列流形具有的某種對稱性，利用該對稱性來降低運算量，並且通過對演算法的研究，提出用維數較小的信號子空間或噪聲子空間來計算空間譜，進一步減小music演算法運算量。This article takes hanging off and wide fluctuation of transmition velocity of adsl as example, then analysis centers on the discerte multiple tone and the principle of channel load assignation. from analysis above article points out the root of adsl being sensible of noise signal. at last, reserches effects that window function and barrier effect on frequency and adopts fft to work out the noise power of adsl
本文以電信現在推出的adsl傳輸中鏈路經常掉線和傳輸速率經常大范圍波動為例，重點分析了adsl所使用的dmt調制方式和注水演算法分配通道載荷方式原理，由此指出adsl對噪聲信號敏感的根源，在得到問題的根源之後，分析了窗函數和柵欄效應對頻譜的影響，採用fft方法計算adsl線路的噪聲功率譜，為adsl線路測試提供了可靠的理論依據。First, the basic theory of the competitiveness is analyzed, evaluating indexes which conclude relative and absolute indexes basic on the last literatures are set up. second, because the data are too many and computing time is too long, the competitiveness of science and technology of 30 areas are clustered using fuzzy clustering model, the areas of the whole nation are clustered several kinds and we can draw some conclusions of same kind. evaluating the competitiveness using single model can produce white noise, so combinational models which concluding neural network, fuzzy theory and genetic algorithm are brought forward to evaluate the competitiveness of areas which are in the same kind with fujian province in the test
本文首先分析科技競爭力的基本理論，並根據以往研究科技競爭力文獻，建立包含絕對指標和相對指標的評價科技競爭力評價指標體系，其次，針對評價福建省科技競爭力在全國范圍內的排名情況數據較多，計算時間較長的具體情況，利用模糊神經網路模型對全國30個省市自治區科技競爭力水平進行聚類分析，將科技競爭力水平接近的地區聚為一類，得出科技競爭力水平相近地區情況，而後，針對已有文獻科技競爭力評價只是利用單一模型可能產生噪聲，影響評價結果，並且主觀性較強的缺點，本文將神經網路、模糊數學、遺傳演算法等智能演算法組合，利用組合評價模型對福建省和與福建省同在一類的其它地區的科技競爭力水平進行橫向、縱向評價，得出福建省在全國范圍內的科技競爭力水平排名。We reconstructed the phase space and calculated the nonlinear parameters such as correlation dimension, the largest lyapunov exponent, approximate entropy, and l - z complexity of the data. it can be conclud from the results that the reconstruction of heart beat rate signal is strange, its correlation dimension is between 5 to 7 and have the character of fractal dimension, its largest lyapunov exponent is larger than zero, its approximate entropy and l - z complexity are obviously differ from noise. we can draw a conclusion from all above : the heart beat rate signal is n ' t simple noise, it is high dimensional chaos obeys certain dynamical law
我們還對信號進行了相空間重構，計算了信號的關聯維數、最大lyapunov指數、近似熵和復雜度這幾個非線性特徵量，我們發現，心率信號的吸引子是奇怪吸引子，關聯維數介於5到7之間，具有分維的特徵，其最大lyapunov指數大於0 ，其近似熵值和復雜度值明顯區別于噪聲，這說明心率信號不是隨機噪聲，它是服從確定性動力學規律的高維混沌信號。In the simulation, we added index weighting noise estimation of measurement noise to improve stability and adaptability of filter
模擬中在線加入量測噪聲的指數加權時變噪聲估計器，使濾波器的穩定性和自適應能力顯著增強。In the second part, the necessity of employing differential demodulation in rapid changing channel was explained, performance of multiple symbol detection of mdpsk and decision feed back multiple symbol detection were analyzed. then we present a new differential demodulation algorithm. the decision data is used to recover the carry phase. given the same observation intervals, this demodulation algorithm has almost the same performance, but the receiver is much more simplified
第二章首先指出了通道參數變化劇烈的情況下，採用差分解調的必要性；分析了多碼元差分解調和數據判決反饋解調演算法的性能和抑制噪聲的能力；在此基礎上提出了一種新的差分解調方案：利用判決數據輔助進行載波恢復，即在判決數據的輔助下，採用fir （ finantimpounsrespouns ）結構對載波相位進行預測的一種演算法，精心設計了該演算法的實現結構。The expressions for correlation functions, power spectrum and correlation time of the intensity of a single - mode laser driven by two white noises with a exponential function correlation form were calculated by linear approximation method
應用線性近似方法，計算了具有指數形式關聯的兩白噪聲驅動下單模激光光強的關聯函數、功率譜及關聯時間。This thesis designs automobile braking performance inspecting and control system. this thesis consists of three main parts. something about automobile braking system design has been discussed in the first part according to the main requirement of gb7258 - 2004 《 the requirement for motor vehicle, running safely 》. the hardware has been designed according to the characteristic of the parameter afer establish the whole plan for inspecting it. and then working principle of each part has been introduced. and at last, we designed software depending on the require to inspection and function. we can educe the braking power of both wheels, braking moment retardarce power and other parameters. we designed sensor signal processing circuit which including power sensor signal processing circuit and speed signal measure circuit according to the require of designing parameter. ad620 is used as power sensor. in order to measure the power of the automobile braking and protect the electromotor. so we must measure both
由汽車制動測試原理以及制動性參量檢測的技術指標可知，檢測數據準確性、控制可靠性、實時性和抗干擾能力是系統設計的關鍵。本文在掌握汽車性能檢測系統結構和原理的基礎上，根據國家有關標準和汽車制動性檢測系統的控制邏輯提出了採用單片機為控制器的總體方案，設計了各部分硬體電路，並根據所要實現的功能用c51語言設計了軟體。由於檢測現場存在各種干擾噪聲，為了保證系統運行的穩定性和可靠性以及測量精度的要求，分別從硬體和軟體的角度出發，介紹了常用的硬體抗干擾措施以及軟體數字濾波的原理和方法。Two conclusions about suspending control system are given in this paper : 1. the single suspending system controlled by parameter self - turning control algorithm has better performance when the mass of single point suspending system, the resistance of electromagnet and the suspending gap are variable ; 2. the single suspending system controlled by global asymptotic stability control algorithm is global asymptotic stability and can restrain the stochastic noise
通過對採用上述控制演算法的懸浮系統的理論分析和模擬研究，主要得到了以下幾方面結論: 1 .當系統懸浮質量、電磁鐵電阻和額定間隙參數變化時，設計的參數自校正控制演算法可使系統的動態性能指標保持在設定的指標; 2 .設計的全局穩定控制演算法，能夠保證二級結構單點懸浮系統的全局漸近穩定，且對隨機噪聲干擾有一定的抑制作用。We expatiate on the theory of ccd from the physical base and point out the different theory of ccd engendering noise. we describe the mathematic model of ccd output noise by correlation theory and analyze the noise quantificationally, it gives the correlation conditions. at these bases, we discuss the correlated double sampling elaborately
課題從ccd的物理基礎入手，闡述了ccd的工作機理，對ccd的各種不同噪聲進行了深入分析，指出了ccd不同噪聲產生的原理，課題運用相關理論對浮置擴散放大器讀出方式工作的ccd輸出復位噪聲進行了數學描述，進而對復位噪聲的相關性進行了定量的分析和計算，給出了復位噪聲相關的條件。This method can guarantee the solution matrix of sylvester equation to be inverse and the sum of the input gain norm and the observer gain norm is the minimum. for the linear systems with unknown parameters, we identify the parameters using hopfield network, then design the observers using the identified parameters, the exponential convergence of adaptive observer is also proved. for the linear time - varying systems, a new network to solve the time - varying sylvester equation is proposed, we analysis it ' s convergence and robustness, then, deign the linear time - varying observer using this network model, and we discuss the convergence of the observer and ruboustness to unknown match parameters
同時保證了sylvester方程的解矩陣的可逆性和觀測器的增益矩陣與輸入矩陣范數的和最小；在設計線性時不變自適應觀測器時，首先利用系統的輸入、輸出數據設計一個hopfield網路參數估計器，進一步設計狀態觀測器，證明了參數估計器和狀態觀測器的指數收斂性；為了仍然從神經優化計算的角度設計線性時變系統的狀態觀測器，最後介紹了一種求解時變sylvester矩陣方程的神經網路模型，分析了它的收斂性和魯棒性，然後利用該網路設計時變狀態觀測器，進一步討論該觀測器的在系統存在未建模不確定和外部噪聲時的魯棒性；最後給出了一種基於分離性原理和hopfield網路觀測器的狀態反饋閉環系統的結構，分析了該閉環系統的特點；對于每一種設計方法都給出了相應的數值模擬例子來進一步表明所提方法的可行性和有效性。Use eda software to simulate the optimization z sand z l in pa designation. 3. theoretically deep analysis is made which is about the method of lna design, analysis the affect of noise figure and input vswr to the system sensitivity and the contradiction between the two parameter
3 .從理論上低噪放設計方法進行深入的研究，系統的分析低噪放的輸入駐波比和噪聲系數這兩項指標對接收機系統靈敏度的影響以及兩者之間的矛盾。分享友人