波定域性 的英文怎麼說
中文拼音 [bōdìngyùxìng]
波定域性
英文
localizationofwave- 波 : Ⅰ名詞1 (波浪) wave 2 [物理學] (振動傳播的過程) wave 3 (意外變化) an unexpected turn of even...
- 定 : Ⅰ形容詞1 (平靜; 穩定) calm; stable 2 (已經確定的; 不改變的) fixed; settled; established Ⅱ動詞...
- 域 : 名詞(在一定疆界內的地方; 疆域) land within certain boundaries; territory; region
- 性 : Ⅰ名詞1 (性格) nature; character; disposition 2 (性能; 性質) property; quality 3 (性別) sex ...
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Digital speech technology has been widely used in many fields of communications in recent years, but it is just at beginning to use acoustical wave to implement underwater digital speech communications, which mainly results from the bandwidth - limited underwater acoustic communications channel and its high temporal and spatial variability
目前,數字語音技術已廣泛應用於許多通信領域,但是在水下利用聲波進行數字語音通信卻是剛剛起步的新技術,這主要是由於水聲通道有限的通信帶寬及其時變、空變等特性所決定的。( 4 ) the correlation property between the distribution of attenuation factor and that of the group velocity is indicated, in this study
( 4 )研究結果顯示,在頻率域內,面波衰減系數分佈與群速度分佈具有一定的相關性。This method applies the extended strip theory to establish the nonlinear ship motion equations in regular head seas, obtains stable time course by resolving in time domain, and then pressure vectors will be available. the pressure includes static pressure, incident waves pressure, diffraction pressure, radiation pressure, and wave impact pressure, and changed with instantaneous draft of each intersection
該方法應用擴展的切片理論建立迎浪規則波中船舶非線性運動方程,通過時域步進求解獲得船舶剛體運動的穩定時歷,進而給出與船體各橫剖面瞬時吃水相對應的靜水壓力變化、入射波壓力、繞射壓力、輻射壓力和波浪沖擊壓力諸分量。Liquid cryatal also use on the public nuisance of chemical industry, the oriented polymer of macromolecular reaction, the nondestructive evaluation and microwave determination of aviational machine and metallurgic product, checking skin cancer in medicine, body temperature measurement, etc. it has showed the great superiority
另外液晶在化工的公害測定、高分子反應的定向聚合、航空機械及冶金產品的無損探傷和微波測定、醫學上的皮癌檢查、體溫測量等領域,也都顯示出其巨大的優越性。This paper starts the research of the liquid floated pendulous accelerometer testing system according to the engineering. at first, this paper gives the brief introduction of the history and present status of accelerometer and its testing technology, the working principium and math model of the liquid floated pendu - lous accelerometer, and then, decides the binary width pulse force retrim loop as the design proposal of testing system, researches the transfer function of every part in the system emphasizly, analyses the stability of the whole accelerometer testing system from the angle of control theoretics by the open loop transfer function of system, and designed the correcting net, analyses the basal problems such as resolution, sampling restraint, precision and so on, designs the hardware testing circuits such as preamplification, band - pass filter, alternating amplifier, phase sensitive demodulatorn, pulse - width modulation, frequency scale circuit, moment current generator. finally, using the graphics program language labv - iew which is designed for testing field especially by ni accomplishes the solfware design of testing system, realized the testing functions
首先對加速度計及其測試技術的發展歷史和現狀,液浮擺式加速度計的工作原理和數學模型等作了簡要的介紹,然後確定了以二元調寬脈沖再平衡測試迴路為設計方案,並從控制理論的角度進行了分析,著重研究了系統中各部分的傳遞函數,利用系統開環傳遞函數分析了系統的穩定性,同時設計了系統的校正網路;分析了二元調寬脈沖再平衡測試迴路的解析度、采樣約束以及測試精度等基本問題,並按照系統分析的結果設計了包括前置放大、帶通濾波、交流放大、相敏解調、脈寬調制、頻標電路以及力矩電流發生器等測試系統各部分硬體電路,驗證了電路的正確性,最後按照測試系統的要求,採用了美國ni公司專為測試領域所開發的虛擬儀器工具? ? labview作為測試軟體開發工具,利用該圖形化編程語言完成了測試系統軟體部分的設計,實現了測試功能。At present, the typic harmful current detection methods are the fast fourier transform algorithm in frequency domain and methods based on the instantaneous reactive power theory, these methods all require some transform and quick, real - time calculating, so high precision analog multipliers or high speed dsp chip with fast a / d are needed, this results in complex circuit and high cost , which have restricted the development of apf
目前畸變電流檢測常用的方法有頻域法的fft和基於瞬時無功理論的畸變電流檢測法。這些方法均有一定的變換,需要快速、實時運算,因此必須使用高速的數字微處理器和高性能a / d轉換器,這必將大大提高系統成本,使得電路結構復雜,在一定程度上限制了有源濾波器的發展。At first, the paper confirms singular area by singular detection, then designs a series of low - pass filters that have different templates according to the different position in finger image for a local area, at last sets up gabor filter parameters according to the characteristics of fingerprint image. the improved enhancement algorithm has a better robust, and can preserve texture structure of singular area effectively. in binary noise clearance, the paper presents an algorithm that clears the biggish white speckles and black speckles
在指紋圖像增強方面,本文針對傳統的基於gabor濾波器指紋圖像增強演算法魯棒性差以及通常會改變奇異區紋理結構的缺點,對原有演算法進行了一些改進:首先通過檢測奇異點確定奇異區,然後根據局部區域在指紋圖像中的位置構建相應取值方式的低通濾波器並對該局部區域方向圖進行濾波,最後根據指紋圖像紋線的特點對gabor濾波器參數進行設置。The former three chapters considers the initial - boundary value problem for the nonlinear wave equation in a bounded domain fi c rn. chapter 2 investigates the problem with a, g and / like ( v2 ) = ( 1 + v2 ) - 1 / 2, g ( v ) = - | v | pv, p > 0 and f ( v ) = | v | mv, m > 0, respectively
論文的主要內容分為四章,前三章主要研究定義在有界區域上的非線性波動方程的初邊值問題在第二章中( v )形式如( 1 + v ~ 2 ) ~ ( - 1 / 2 )In light of the limitation of fast fourier transform ( fft ) for the method of traditional spectrum analysis to analyze the unsteady signal, wavelet and wavelet analysis are made for the typical unsteady process signal of starting up and shut down with the good characteristic of simultaneous localization in both the time and the frequency domains based on the field test on the vibration of two - row placed units in lijiaxia hydropower station, in which the signal is decomposed into different frequency band, and then the weak signal is caught and the dominant frequency is picked up for the analysis of the vibration source
摘要基於李家峽水電站雙排機組振動的現場試驗研究,並且針對傳統頻譜分析方法傅立葉變換( fft )對于非平穩信號已力不從心這一缺陷,利用小波分析方法在時域和頻域上同時具有良好的局部化性質,通過對開停機這一典型非平穩過程信號進行小波及小波包分析,將其分解到不同頻帶內,獲取微弱信息和提取優勢頻率,並對其作振源分析,得出開停機初始時刻因水流不穩均出現強烈的振動現象,且低頻段信號能量最大,開停機過程水流脈動壓力和尾水渦帶擺動是引起定子基礎振動的主要原因。By calculating instability factor in research area, this paper gives some corresponding suggestion. this paper shows engineering instability around instrument foundation and coupling relation to the circumjacent seabed, and research the dynamic response between wave and seabed, and enriches the research content of instability of seabed around instrument foundation and give some appropriate suggestion to foundation planning of ocean engineering, also it prevents instrument, facility and property of state from losing and risking
這篇論文揭示了構築物地基土的工程穩定性及與周邊海域互動禍合關系,研究了淺水區構築物底床在波浪等水動力作用下的動力響應,豐富了構築物周邊水下底坡穩定性研究的內容,為海上工程設施的地基設計提供了良好的理論指導性建議,對保障海上安全生產、保證海洋設施的完整及使國家財產免受損失也有重要的現實意義。We provided a new method that tried to transform the whole image to featured space and facilitated identification and self - elimination of disturbance according to the hue and luminosity features of eyes of human being. we gave the definition and description of the transformed space. a wavelet - texture filter was designed to distill space - transform - based feature of the image itself was executed
根據人眼對顏色、亮度等不同的敏感性以及圖像本身的性質,仿人眼變換域分析圖像形成光學濾色鏡效果,減少復雜背景顏色和相似形狀的多重干擾,並以此定義和表徵變換域特徵空間,給出變換域小波紋理車牌特徵,成功提取車牌字元區域; 2The paper includes four sections followed here : the first section studies the modeling of signals of pulse doppler radar seeker, and establishes a radar signal simulation model, including radar emitting signal model, receiving signal model, receiving echo signal model, clutter model, noise model, sum channel directional pattern of antenna model, difference channel directional pattern of antenna model, sheltering model, rcs model, glint noise model, etc. the second section studies signal processing of pulse doppler radar seeker, and establishes radar signal processing mathematical model and data processing mathematical model for simulation, including windowing, doppler filtering, envelope demodulation, pdi, cfar, centering, velocity tracking, angle tracking, a - b filtering, etc. the third section studies the modeling of modified proportion guiding, and establishes guiding model, then dynamic simulation results is provided
論文的主要工作包括四部分:第一部分研究了脈沖多普勒雷達導引頭的信號建模問題,建立了雷達信號模型,主要包括:發射信號模型、接收信號模型、目標回波信號模型、雜波模型、噪聲模型、和差通道天線方向圖模型、遮擋因子模型、接收機噪聲模型、目標雷達截面積統計性模型、目標角閃爍模型等。第二部分研究了脈沖多普勒雷達導引頭的信號處理模式,建立了信號和數據處理模型,主要包括:加窗和多普勒濾波、包絡檢波、檢波后積累、頻域cfar處理、速度定心、速度跟蹤、角跟蹤、 ?濾波等,然後給出了信號處理流程。Finally a set of equations with initiate values for boundary value problem is established where the velocity potential and its normal derivative are unknowns. because the model includes the effects of both the time and space to the velocity potential of free surface, it can be applied to strong nonlinear wave. as examples, solitary wave is computed in the numerical flume
推導給出計算域內以所有節點波勢函數和波面位置高度的時間增量為未知量的線性方程組,並同時考慮時間因素和空間變位對波面勢函數的影響,在預設的計算精度下,通過時步內的循環迭代逐一確定每個時步上的波面運動位置,從而建立了一種可適于求解強非線性波浪變形計算的數值模式。Comprehensively discuss the issues in application, adaptive condition and performance, propose a fast arithmetic of forward modeling and depth migration in common shot gathers with one - way acoustic wave equation based on vrselrf, and verify the arithmetic by numerical simulation. concisely discuss the cause of the creation of evanescence and the problem of lateral amplitude discontinuity result from it. fourthly, use the reflectivity model, computed to describe the fracture model, with the formula of computation reflectivity based on elastic - acoustic approximation, and the wavelet model computed by the method, wavelet creation with fourier transform, we proposed, in conjunction with vrselrf wavefield extrapolation operator
第三,將頻率波數域穩定的變參考慢度rytov近似廣義屏波場延拓運算元( vrselrf )應用於疊前與疊后正演模擬、疊前與疊后深度偏移,對演算法應用中應注意的問題、適用范圍、性能等作了較為全面的論述;提出了基於vrselrf的單程聲波方程共炮記錄正演模擬和深度偏移快速演算法,並通過數值模擬試驗對演算法進行了驗證;簡要地討論了倏逝波的產生原因及其帶來的橫向振幅不連續性問題。After an introduction to the concept and property of the wavelet and present applications in communications, this dissertation focuses the research on the wavelet ' s application to extraction and analysis of the fine features of typical communication signals, and four problems are discussed : ( 1 ) an new method for the feature extraction and pattern recognition of typical communication signals a distinct method based on wavelet transform is proposed
本文在簡要回顧了傳統小波的定義、性質、發展歷史和目前小波在通信領域中的應用后,著重研究小波在典型通信信號細微特徵提取與分析方面的應用,主要研究工作和研究結果集中在四個方面: ( 1 )典型通信信號特徵提取與模式識別的新方法。通信信號的特徵提取與模式識別在通信對抗領域有著重要應用。Author, secondly, starts from the approximate expandness of square root operator, perform mathematical calculations for finite difference operator in frequency - space domain, fourier finite difference operator in mixing domain ( frequency - space and frequency - wavenumber domain ) and general screen operator in mixing domain, compare and discuss their precision of their wavefield, adaptability for lateral velocity variations, computation efficiency and stability. thirdly, author, applies the steady variational reference slowness rytov approximation general screen wavefield extrapolation operator ( vrselrf ) in frequency - wavenumber domain, to the prestack and poststack forward modeling and depth migration
第二,從平方根運算元的近似展開出發對頻率?空間域的有限差分運算元、混合域(頻率?空間域;頻率?波數域)的fourier有限差分運算元、混合域的廣義屏運算元進行了推導並對其波場描述精度、對橫向變速的適應性、計算效率和穩定性進行了比較與評述。According to the seismic convolution model, a kind of matched filters in time - scale domain is designed for echo signal detection of ground penetrating radar ( gpr ) and implemented in this paper, which is applied to detect the location and amplitude of single reflection wavelet in receiving signal through continuous wavelet transform
摘要根據地震褶積模型,設計並實現了應用於探地雷達回波信號檢測的時間尺度域匹配濾波器,利用小波變換的時間定位性和尺度伸縮性,檢測出雷達接收信號中單個反射子波的位置與強弱信息,利用已知的雷達發射子波模型還原回波信號,達到了濾除噪聲、最佳接收的目的。The calculation of the position of the shocks for the domain decomposition of the hyperbolic approximation is discussed. it is the matching stable problem for the different schemes in the different domains with different mesh size. after tracing the position of the shocks, the artificial compression method are applied to eliminate the smearing effect and to raise the resolution of the schemes. in the boundaries of each regions, the universal connected matching stable schemes are inserted in so as to make the schemes between different regions matching stable each other. at last, some numerical examples are presented
討論在激波計算中的區域分解法,即在不同區域中應用不同網格及格式的耦合穩定性問題.先定出激波位置,再在激波附近小范圍內,用低階格式及人工壓縮方法以消除彌散效應.在激波區域外,應用高精度格式,減少了過超振蕩現象,提高了解析度.在各區域交界應用全能穩定聯接格式,解決了格式的耦合穩定問題.最後舉出數值計算實例,計算結果與理論分析符合The green ' s function for point - source excitation is also very simple in homogeneous media. however, since global basic functions like plane waves occupy the entire domain and point source excitation radiates to all directions, their evolution through a non - homogeneous medium constitutes a problem that may become at least as difficult to solve as that of the propagation of the total field
例如dirac函數(點源)在空間域可以有精確的定位,但在傳播方向上(波數域)卻毫無確定性;而平面波(波數域的基本解)則具有精確的傳播方向,但其波前卻是無限延伸的,不具任何空間局域性。When discreting the sonic and elastic analytic equation, the paper shows different finite - difference forms of sonic and center finite - difference form of elastic by detailed deriving in different situation. at the same time, the paper discusses the finite - difference ' s stability and the boundary conditon of gridding region, then lists the final sonic and elastic finite - difference expression which can realize forward modeling and inverse in computer by programming
在對聲波與彈性波解析表達式進行離散時,論文按不同情況進行了詳細的推導,由此得到聲波方程各種不同的差分格式和彈性波的中心差分格式,在此基礎上還對差分方程穩定性條件與網格區域邊界處理進行了討論,最後得到完整的能在計算機上進行正反演編程運算的聲波與彈性波有限差分格式。分享友人