低噪聲線路 的英文怎麼說
中文拼音 [dīzàoshēngxiànlù]
低噪聲線路
英文
low-noise line-
Noise of a running train will be mitigated by low vibration track, floating slab track, train skirts and a multi - plenum system to attenuate airborne noise at source
為減低列車經過時所產生的噪音，支線的路軌會裝置彈性底板及浮動平板，列車亦會裝上裙邊及多重隔音系統，以消減因結構震蕩而產生的聲音。Low noise amplifier ( lna ) is widely used in front end of a received set of mobile communication 、 wireless radio 、 blueteech technology and so on 。 the active device is the core of the circuit and has significant effects on the whole equipment, therefore, the design of the active device is vital in lna
微波低噪聲放大器（ lna ）廣泛應用於移動通訊、無線電、藍牙技術等的rf前端。 lna中的有源器件是整個電路的核心，對整個放大器電路的性能有著重要的影響，因此有源器件的設計是lna的關鍵技術之一。Two nonlinear simulation methods are designed by curve fitting method and anfis which seem simply and right in the simulation experiment. based on the model different control strategies also were realized in detail such as chopped current control ( ccc ), angular position control ( apc ), amplitude - change ccc and pi control. a simple torque sharing function ( tsf ) method and a tsf controller were designed which decreases torque ripple effectively
文章中還建立一種基於模糊神經網路的非線性模型，並對比分析了三種方法，模擬中確定了電機的最優開通關斷角，在此基礎上實現了電流斬波控制、角度位置控制、變幅值電流斬波控制以及分段雙閉環pi控制，模擬結果表明，它實現了電機的正常運行，很好的抑止了電機轉矩脈動，同時有效地降低了噪聲。On the base of studying imaging theory of lens, the imaging theory of laser confocal scanning microscopy was analyzed in detail in this paper, and the advancement of that the optical fiber was applied to the system was described ; on the base of completed the demonstration for whole project, the experiment scheme was designed ; the relationship between the main parameters of key devices and the resolution was deduced, and the requirements of coupling efficiency and vignetting effects to optical system was analyzed ; the design of optical system and the planar scanning controlling circuit was completed ; a new method was put forward to resolved the inherent non - liner scanning problem of the galvanometer scanner by using software liner controlling in circuit design, and the perfect planar scanning was realized ; at last the low noise, high multiple and non - distortion amplify circuit of photoelectric detector was completed
本文在透鏡成像理論的基礎上，系統、深入地分析了共焦掃描顯微成像的機理，論述了應用單模光纖的激光共焦掃描顯微成像系統的優點；進行了總體方案的論證，並設計確定了單模光纖激光共焦掃描顯微成像系統的總體方案；從理論上推導分析了解析度要求與試驗系統中相關器件主要參數之間的關系，分析了系統耦合效率和漸暈現象對光學系統的設計要求；完成了方案中光學系統和二維掃描控制電路的設計，並在電路設計中採用了用軟體解決檢流計式光學掃描器（振鏡）非線性問題的新方法，能夠實現較為理想的二維模擬掃描；完成了高增益、低噪聲和低失真的探測接收系統的設計和調試。The dialing is slow and the system ca n ' t ensure the calling party fast and accurately put through the called one who is asked for receiving. 5. the bell ring is so low that the workers ca n ' t hear in the large - scaled working space with strong noise
它存在的缺點有：工程布線麻煩、費用高；電話線路成本高且利用率低；系統可靠性差；呼叫速度慢，並且不能保證主叫用戶快速、準確地找到需要接聽的被叫用戶；振鈴聲難以保證在大范圍、強噪聲的生產場所下的工作人員接聽到。In the following chapters, a 16 - channel experimental phased array ultrasonic testing system is thoroughly explained, including digital beam forming, low noise programmable amplification of received ultrasound signal, multi - channel hi - speed hi - precision data acquisition, hi - speed real - time processing of multi - channel ultrasound signal, and hi - speed data transfer based on pci bus. in addition, the frame of software system is built
本文詳細闡述了作者所獨立研製的16通道相控陣超聲檢測實驗系統，包括數字化超聲發射/接收波束形成、超聲信號的低噪聲程式控制放大、多通道高速高精度數據採集、多通道超聲信號高速實時處理、基於pci總線的高速數據傳輸等全部電路模塊的結構及工作原理，並說明了所編寫的底層軟體系統的框架。The major noise sources of low - speed railway vehicles ( v 200km / h ) running in domestic existing lines are wheel - rail rolling and structure noise
我國既有線鐵路客車運行速度多在200km h以下，屬于低速運行。運行噪聲以輪軌噪聲和構造物噪聲為主。In the system, the low voltage power line is the first signal tunnel without any other relay equipments between customer terminal and substation collector, public telephone line serves as the second signal tunnel between substation and management center computer. as a breakthrough of conventional concept of electricity meter, this thesis initiate a new concept, namely, intelligent power customer terminal ( shortly, customer terminal ), which is developed with spread spectrum plc communication functional and possesses many advanced functions, such as, in addition to electric energy acquisition, guarding against electricity pilfering, preventing wrong connection, protecting malfunction, remote communication ( for example, remote power supply or halt, remote configuration of electricity meter, remote load control, etc ), and so on
本文首先系統地總結了目前國內外低壓電力網數據傳輸技術的研究現狀和存在的問題，在此基礎上，從理論上論證了在低壓電網上應用擴頻載波數據通信技術的可行性和優越性，並重點論述了擴頻載波技術抗電力線噪聲干擾的機埋；本文提出了一個新穎的基於低壓電力線擴頻載波通信技術的集中遠抄系統的總體方案，即由用戶終端、集中器和電能管理系統所組成的網路系統，其中，用戶終端到配變集中器用低壓電力線作為通道，中間無需其他硬體中繼設備，集中器到電能管理系統用公用電話網作為通道。In order to overcome problems arisen from the application of x fluorescence analysis into complex spectrum produced by archaeological ceramic fragments with multi - element, low content and thick ground, we have employed the artificial neural network into the research of x fluorescence archaeology and conducted three kinds of research works. as the first one, we have applied the linear olam network ( optimal linear association memory network ) and the non - linear bp network ( back - propagation network ) respectively to analyze the complex x fluorescence spectrum of archaeological samples, and taken both results of spectrum analysis to compare with each other. the second, the method of pattern recognition of bp network was tentatively used to perform intelligent identification of production places of these archaeological samples
針對科技考古中對大量考古陶片進行產地研究時x熒光分析對多元素、低含量、厚基底考古陶片產生的復雜譜分析的問題，將人工神經網路引入x熒光考古中，進行了三方面的研究工作：一是用線性olam網路（最優線性聯想網路）和非線性bp網路（誤差反傳導網路）分別對考古樣品的x熒光復雜譜進行解譜，並比較二者的解譜效果；二是用bp網路模式識別方法對考古樣品的產地進行智能識別；三是為了提高網路運算的可靠性和減小基體效應及電噪聲的干擾和影響，研究並提出了三種網路學習前的譜數據預處理方法。As umbirfpa is a new type of infrared detecting device, its work principle is complex and its performance is affected by many factors. in the initial stage of developing, the design experiment and theoretical understanding are little interiorly. furthermore, the problems such as sensitivity reduced, dynamic range shortened, nonuniformity increased come forth if umbirfpa is not designed properly
Umbirfpa是一種新型的紅外探測器件，微測輻射熱計的工作原理復雜，其性能受到很多因素的影響，目前國內尚處于發展初期，缺少實際的設計經驗和理論認識，同時umbirfpa又是在集成電路工藝線上生產的，投資大、周期長，如果設計不當，不僅可能導致靈敏< wp = 13 >度降低、動態范圍縮小、噪聲增大、非均勻性增大等問題，更可能的是根本就不能用於成像，從而造成很大損失。For recent years, adsl has world widely employed and widely used in many aspects such as vod, remote medical treatment and e - shopping etc. but we noticed that the traditional telephone networks are designed for the transmission of low frequency signals, and the adsl ' s frequency rang is from 0 to 1. 104mhz, so we must confront the signal attenuation, the loop line noise impairments, the crosstalk interferences, the bridge tap reflections and the rf disturbances problems and many other problems when transmitting the adsl signals one the telephone networks
近幾年來， adsl在世界范圍內得到充分的使用，廣泛應用於視頻點播、遠程醫療、網上購物等各個方面。但是由於電話線網路是專門為傳輸低頻信號而設計，而adsl的頻譜范圍在0 1 . 104mhz內，因此在傳輸adsl信號時，面臨著信號衰減、線路噪聲、串音干擾、橋接抽頭反射和射頻干擾等等多方面的問題，這就要求在adsl開通之前對線路進行一系列的測試。Moreover, its interior pll circuit substitutes traditional pll. as a result, the presented design not only overcomes some shortcoming of traditional circuit such as tracking speed and accuracy, but also gets rid of response lag time and multi - phase noise. the system design is also important to improve our country ' s fault diagnosis standard
而該系統內部鎖相電路代替了傳統方法中的pll ，因此，提出此系統設計不僅能夠克服基於傳統鎖相環電路的等轉角采樣方法跟蹤精度低、速度慢和使用不便等特點，還能克服電路中的由於不可避免的響應延遲時間所導致的不適合快速的列車運行及過多的相位噪聲問題，對于推動我國鐵路故障在線診斷技術的應用普及具有重要意義。Low noise amplifier ( lna ) is a key component in the front - end of rf transceiver
低噪聲放大器（ lna ）是無線收發機前端的關鍵電路之一。System scheme of speech coding plus spread spectrum communication was presented based on a full analysis of noise characteristic, attenuation characteristic and impedance characteristic of low - voltage power line. spread spectrum carrier ( abbreviated as ssc ) technology is adopted to overcome problems existing in signal transmission over power line. high quality, low rate mbe compression algorithm was used to complete speech encoding and decoding
在對低壓電力線路的噪聲特性、衰減特性和阻抗特性三個方面充分分析的基礎上，本文提出一種語音編碼+擴頻傳輸的系統總體方案，採用擴頻載波（ spreadspectrumcarrier ，縮寫為ssc ）技術克服電力線傳輸信號存在的問題，採用語音合成質量高並具有較低碼率的mbe壓縮演算法完成語音信號的編解碼。Thirdly, the wire size variations, vertical balance, insulation and joint features on adsl lines will affect the insertion loss and introduce additional noise, thus reducing the transmission rate and degrading the transmission performance. fourthly, the bridge tap on the adsl line will greatly change the frequency response and phase - frequency features of the line insertion loss
第三，線對線徑的改變、線路的縱向平衡性、線路的絕緣性能和線路接頭的性能將影響線路的插入損耗、引入附加噪聲，從而降低adsl的傳輸速率，影響adsl的傳輸性能。In receive channel, the low noise amplifier make the signal which received from the antenna enough strong to demodulation
而低噪聲放大器用於接收鏈路中放大天線接收到的微弱信號，使信號電平達到解調單元所能分辨的電平。2. on the base of detailedly analysing the fourier neural networks, we find this neural networks have the characteristic which can transform the nonlinear mapping into linear mapping. so, we improve the original learning algorithm based on nonlinear optimization and propose a novel learning algorithm based on linear optimization ( this dissertation adopts the least squares method ). the novel learning algorithm highly improve convergence speed and avoid local minima problem. because of adopting the least squares method, when the training output samples were affected by white noise, this algorithm have good denoising function
在詳細分析已有的傅立葉神經網路的基礎上，發現傅立葉神經網路具有將非線性映射轉化成線性映射的特點，基於這個特點，對該神經網路原有的基於非線性優化的學習演算法進行了改進，提出了基於線性優化方法（本文採用最小二乘法）的學習演算法，大大提高了神經網路的收斂速度並避免了局部極小問題；由於採用了最小二乘方法，當用來訓練傅立葉神經網路的訓練輸出樣本受白噪聲影響時，本學習演算法具有良好的降低噪聲影響的功能。By designing the circuit structure of preamplifier and selecting new elements such as ultra low noise operational amplifier and linear opto - coupler, some difficulties in eeg acquisition is overcome and the common mode rejection ratio ( cmrr ) of preamplifier is highly increased. so eeg can be amplified and detected well
通過對前置放大器等電路結構的精心設計，選用超低噪聲的集成運算放大器以及線性光耦合器等新器件，克服了腦電信號採集中經常遇到的一些困難，使前置放大器具有較高的共模抑制比，從而能夠較好地放大檢測出所需的腦電信號。分享友人