頻次特徵 的英文怎麼說

中文拼音 [bīnzhǐ]
頻次特徵 英文
frequency characteristic
  • : Ⅰ形容詞(次數多) frequent Ⅱ副詞(屢次) frequently; repeatedly Ⅲ名詞1 [物理學] (物體每秒鐘振動...
  • : Ⅰ名詞1 (次序; 等第) order; sequence 2 [書面語] (出外遠行時停留的處所) stopping place on a jou...
  • : Ⅰ形容詞(特殊; 超出一般) particular; special; exceptional; unusual Ⅱ副詞1 (特別) especially; v...
  • : 名詞[音樂] (古代五音之一 相當于簡譜的「5」) a note of the ancient chinese five tone scale corre...
  • 特徵 : characteristic; feature; properties; aspect; trait
  1. By performing fourier transformation, the relationship between the turbulent intensity of the particle and that of the carrier fluid was obtained which makes clear that particle size, specific gravity, velocity gradient, and the characteristic frequency of energy - containing eddies are four basic influencing parameters. it is proven theoretically that under certain conditions, the stream - wise and transverse particle turbulent intensities exceed those of the carrier fluid. based on the equations of two - phase flow, the presence of fine sediment suspension is shown to attenuate the turbulent intensity of the water

    通過對細小顆粒在剪切流場中運動方程的fourier分析,得到了顆粒脈動強度和流體脈動強度之間的定量關系,表明顆粒粒徑、顆粒密度、流速梯度以及紊動場含能旋渦的率是影響顆粒脈動強度的主要因素,首從理論上證明了在一定條件下,顆粒在縱、垂向的脈動強度均會超過相應的流體脈動強度,為已有的實測資料提供了合理的解釋。
  2. The potential applications of amr include both civil and military communication, especially non - cooperative communications and communication confrontation, such as identifying signals, supervising signals, distinguishing interference, electronic confrontation, analyzing military threat, etc. on the basis of our analysis to the existing research on feature abstraction, the related feature abstraction methods are optimized in this paper, resulting several effective methods such as the feature abstraction based on transformation domain, stepped voltage level analysis, normalized carrier - free spectral energy analysis, squared signal and fourth powered signal analysis, etc. both the decision theory based on recognition algorithms and the artificial neural network ( ann ) based on recognition algorithms is analyzed, and the former is selected as it is more appropriate for this research

    調制類型的自動識別廣泛應用於民用通信與軍用通信,尤其是對于非合作性通信、通信對抗,比如:信號確認、信號監控、干擾辨識、電子對抗、軟體無線電、電子救援、通信對抗、軍事威脅分析等。本論文在分析現有研究的基礎上,借鑒了已有的提取方法,對相關調制類型提取方法進行了優化,使用了一些有效的方法,如基於變換域提取方法、梯層電平分析方法、剔除載波后的歸一化域能量分析方法、信號平方后的譜分析方法、信號四方后的譜分析方法等。通過對基於決策理論和基於人工神經網路兩種識別演算法進行分析,本論文選擇了較適合的基於決策理論的識別演算法。
  3. Secondly, the paper researches blind estimation of signals parameters, including the carrier frequency, signal to noise ratio and symbol rate of digital modulations. thirdly, with the combination of parameters from early studies on the decision theory, a set of robust feature parameters are extracted from signal power spectrum and the power spectrum of the second and fourth power of signal. based on these parameters, the proposed scheme is able to recognize 12 types of common used modulations, namely ask 、 2fsk 、 msk 、 4fsk 、 psk 、 qpsk 、 / 4qpsk 、 8psk 、 am 、 dsb 、 ssb 、 fm

    接著,對信號功率譜、平方譜及四方譜進行研究,針對通信中常用的調制方式,結合前人提出的基於決策理論中的參數,設計了一組對信噪比和信號調制參數不敏感的分類參數,利用上述參數完成了一種基於信號域的識別方法,可以對ask 、 2fsk 、 msk 、 4fsk 、 psk 、 qpsk 、 / 4qpsk 、 8psk 、 am 、 dsb 、 ssb和fm這12種常用調制方式進行識別。
  4. In our model, videos are represented in a hierarchical structure with four layers from frame, shot, scene to story unit, and key frames, etc. are introduced to describe the features and contents of layer

    該模型描繪了從幀、鏡頭、場景到故事單元的結構化層,並引入關鍵幀等概念分別描述每個層的視
  5. This paper outlines some features from the perspective of the concept of prefabricated phrases and elaborates for the first time the effect advantage in regard of lexicality frequency, semanticality and context, combining mental lexicon access affecting factors

    從預制語塊的概念出發概括了預制語塊的某些,同時結合影響心理詞匯提取的因素首闡述了預制語塊所具有的詞、語義與語境效應優勢。
  6. Consumer ' s personal characteristic including education, age, job, engaged in trade, family ' s monthly gross income, situation of relocation household and live in the area now, and the commercial residential building demand includes the house - purchase purpose, buy property frequency, house type demand, structural demand, house demand characteristic, house - purchase influence factor, sets of type area demand and price endurance, etc

    消費者個人包括學歷、年齡、職業、從事行業、家庭月總收入、拆遷戶情況和現居住區域,而商品住宅需求包括購房目的、置業、住宅類型需求、室內結構需求、住宅需求、購房影響因素、套型面積需求和價格承受能力等。
  7. Data used in this work are north pacific ssta, 160 stations precipitation of china, and ncep reanalysis data. main results are as follow : ( 1 ) it is found that a apparent transition of north pacific ssta in later 1970 ' s : eastern and middle - equatorial pacific ssta turns from cold to warm with area extending, and mid - latitude pacific ( west wind drift zone ) turns from warm to cold. during this transition of ssta, different characters also appear in el nino and la nina : before 1976, la nina happens more frequently, and its duration is longer, el nino zone develops from negative ssta in the early stage ; after 1976, el nino happens a little bit frequent and longer with more intensity than before, el nino zone develops from positive ssta in the early stage ; the course of ssta variation has an enso cycle of 2 - 6 years, annual oscillation of 8 - 9 years, and decadal variation of about 22 years

    本文採用1950 - 1999年北太平洋海表溫度( sst ) 、中國160站夏季降水和ncep再分析的歐亞500hpa高度場等資料,利用eof 、 svd 、小波分析、合成分析和相關分析等方法,在分析北太平洋海溫時空分佈的基礎上,著重探討了海溫異常及其年代際變化對我國東部降水的影響,並對降水、高度場和海溫三者之間的關系進行了分析,以試圖尋找三者異常之間可能的聯系,主要結論如下: ( 1 ) 1976年前後,北太平洋海溫經歷了一明顯的轉變,赤道中、東太平洋厄爾尼諾海區由冷轉暖,暖水范圍增大,中緯度西風漂流區海溫由暖轉冷;在這樣的年代際背景下,厄爾尼諾、拉尼娜事件在不同的時期也有不同的:在76年前,拉尼娜事件發生率高,持續時間長,事件起始於負海溫距平;而76年後,則是厄爾尼諾事件發生率略高,持續時間長,強度增大,事件起始於正海溫距平。
  8. Visual analysis of human motion has been receiving increasing attention from researchers in the fields of image processing and computer vision during the past few years. it has a lot of applications in virtual reality, smart surveillance system, advanced user interface, motion analysis and video compressing, etc. this paper focuses on the technology of human motion tracking based on video, first, we make a summarization of the domestic and overseas status of the research in this field. on the basis of this, we analyse the technical difficulties of human motion tracking. as most of the existing model - based methods of human motion tracking perform not so good in some situation as they need mannual intervention, and also the precision of tracking is not so satisfying during the research of tracking of walking people because of the self - occlusion of legs, this paper proposes an algorithm of automatic detection and tracking of legs of the walking people based on monocular image sequences, in which we analyse the features of walking people, track the five joints of lower limbs, get various parameters, and then re - construct the walking process. the main research achievement is as follows : 1 ) we propose an algorithm of markerless automatic extraction of leg skeleton. first we divide the video into continuous image sequences, after background subtraction, the satisfying human region could be extracted, then we get a single - connected region by converting the rgb image to binary image and median filtering. afterwards, the contour of lower limbs in the frame with a widest boundingbox is detected, using sobel operator, to find the ankle joint of leg behind according to the features and rules of walking, then, the joint of knee of leg behind, hip, ankle of leg in front, knee of leg in front could be got in turn. so, model of leg skeleton is constructed

    首先將視分解成許多連續的靜態圖像幀,經過背景去除,把感興趣的人體區域提取出來,通過二值化,中值濾波等預處理方法得到只有人體的一個單連通區域,然後用sobel運算元檢測出boundingbox最寬幀中人體下半身的輪廓,根據運動規律及找到後腿踝關節點,結合從boundingbox最窄幀中所獲取的腿長依得到後腿膝關節,跨部關節,前腿踝關節,前腿膝關節四點,從而構建出腿部骨架模型。 2 )實現了人體步行腿部骨架的跟蹤演算法。在完成對腿部骨架模型的自動初始化之後,本文對跨關節、膝關節及踝關節分別採用運動建模、圓周相交定點演算法、運動預測及預測點周圍搜索rgb相似矩形塊三種方法確定每一幀中其實際坐標,從而重構出腿部骨架的運動過程。
  9. In order to make comprehensive analysis on the changing behaviour, the author has investigated and verified all of the a share listed companies that have changed use of proceeds since the foundation of chinese stock market. firstly, this chapter analyzes the general situation. secondly, this chapter makes detailed statistics and analyses on the 5 aspects of the changing behaviour

    本章首先考察了上市公司募資變更的總體情況;接下來從募資投向變更的數、率及幅度,變更過募資投向公司的行業,變更募資投向的公告原因,改變過募資投向上市公司的地區分佈,以及募資變更前後的投向等5個方面進行了詳細的數量統計和分析。
  10. The wavelet packet analysis applied in fault diagnosis system is studied in this thesis. using simulation fault data, uncalm and time difference vibration signal of sodium pump are decomposed on different levels and frequencies. to picked - up the eigenvectors reflecting different fault of sodium pump with availability, simulation results have shown its satisfaction in the identification

    對小波包分析應用於故障診斷進行了研究,利用模擬出來的故障數據,將快堆鈉泵非平穩時變振動信號分解到不同層和不同帶上,有效地提取出反映鈉泵不同故障(狀態)的向量,在識別中得到了滿意的結果。
  11. As urban is the region where the human behavior has effect on nature landscape ecological system most frequently and acutely, the research on land use of urban and its change has arouse people ' s interests. based on the data of land use investigate and remote sensing, the land use dynamic change of beijing chosen as the research flat from 1992 to 2001 has been opened from three level ( total city, district, sample area )

    而城市作為人類行為對自然景觀生態系統作用最繁和最劇烈的區域,它的土地利用及其變化引起了人們的研究興趣。本文選擇北京市作為研究平臺,在土地利用調查數據和多時段遙感數據的支持下,試圖從三個層(全市、區域、樣區)來揭示1992 2001年北京市土地利用動態變化時空
  12. Therefore the dynamical characteristic is acted as detected parameter for fractured detection ( primary amplitude secondary frequence ). and the amplitude of mean sguare and central frequence are acted as evaluational parameter, based on the those studies, the new ideas is put forward that fractured azimuth is dected by lateral difference and fractured density is dected by vertical difference for three facters of fracture, wavelet acted as analysis tool and direction by wave field characteristic applied the multiple scale edge dectection and self - adaptive edge detection into the detection theory of seismic fractured azimuth, also put forward the wavelet different scale filter method of the fractured azimuth detection

    因而,確定了主要以振幅,其率的地震波動力學作為裂縫檢測的被檢參數和均方振幅和中心率作為檢驗檢測結果正確與否的評價參數。在上述研究基礎上,針對裂縫的三要素,提出通過橫向求異檢測裂縫方位和縱向求異檢測裂縫密度的新思想。並以小波作為分析工具,以潛山波場作指導,將數字圖像處理中的多尺度邊緣檢測和自適性邊緣檢測引用到地震裂縫方位檢測中來,並提出了小波變尺度濾波法新的裂縫方位檢測法。
  13. Finally, some important conclusions were drawn, that is, using distributed pzt transducers, ultrasonic guided waves are generated and received in a pipe. usually, there are many different modes of guided wave propagating in the pipe and these modes are generally dispersive, the specific exciting signal of a harming windowed toneburst with a central frequency of 70khz for decreasing the effect of dispersion was selected. and guided wave are generated using 16 distributed pzt transducers in a circumferential direction for suppressing flexural modes

    首先,對當前本課題研究領域的進展作出綜述,並簡要介紹與超聲導波技術相關的理論基礎;其,建立了一套有效的實驗裝置,在此實驗裝置基礎上,重點研究了採用分散式pzt傳感器在管中激勵和接收定模態超聲導波的方法:根據在管狀波導中傳播的超聲波具有散現象及多模態,選擇具有單一率的定信號激勵超聲導波,使其散最小;同時採用分散式傳感器抑制不同模態的波型。
  14. Abstract : in order to process signal in depth and to extract the fault feature from original signal in machinery diagnosis , the graphical display algorithm that can keep the data length of wavelet transform results the same as that of original signal is used. the fault diagnosis of a bend axial piston pump via b - spline wavelet that has linear phase is provided. the results of study demonstrate that the new method has excellent feature and the weak fault signal can be extracted from the strong vibration background of the pump

    文摘:採用具有線性相位的b樣條小波,應用圖形顯示演算法並結合小波變換快速演算法將信號分解到不同的帶上,且分解結果和原信號長度保持一致,可對信號進行深層的處理,克服了傳統的信號處理方法不易提取微弱信息的不足.通過對礦用斜軸式柱塞泵振動信號的分析,分離出了配流副磨損、球鉸松動、缸體及泵軸支撐軸承的故障,為液壓泵的故障診斷提供了依據,並為信噪分離、微弱信號提取及設備的早期故障診斷提供了一條有效途徑
  15. Fourier transform method use high order frequency to analyse and imitate nonlinear and non - stationary data. emd method based on local characteristic time scale of the data is more fit to analyse nonlinear and non - stationary data than fourier transform method

    Emd基於信號的局部時間尺度分析原信號,克服了傅里葉變換用高諧波率分量擬合非線性、非平穩信號的缺點。
  16. O curve of dsdp607 v30 - 97 show that loess began to deposit on the terrace of the yellow river about 1. 20 ma b p, and passed thirteen climatic changes from drier and cooler to warmer and wetter later. the turn of sedimentation from alluvium to loess, an event of transformation from accumulation to down - cut of the yellow river, indicates a sharp tectonic uplift occurred around 1. 2 ma b p. key words : loess - paleosol ; susceptibility ; climatic changes ; tectonic movement ; yellow river ; yangfan section

    通過對楊范剖面黃土地層巖性沉積結構質量磁化率和率磁化率的分析及與深海氧同位素曲線的對比,劃分了剖面地層,初步確定了黃土沉積始於1 . 20 ma b p ,黃土沉積以來該區發生了13大的乾冷暖濕氣候變化沉積轉型指示河流強烈加積轉變為河流侵蝕,代表約在1 . 20 ma b p發生過一強烈的構造抬升事件。
  17. Second, a jeffcott rotor model supported by two seals bearings in its two ends is established to simulate the shafting of simple turbines ( only short - and - straight - blades are included in the shafting ). and periodical response of the system is obtained by using the newmark method. then, the dynamic characteristics of rotor system at the certain rotate speed and the certain physic

    ,建立了一個用來模擬簡單汽輪機軸系(只含有短直葉片)的兩端用滑動軸承支撐的jeffcott轉子模型,並用newmark方法求得了系統的周期響應,根據系統的周期響應、 poincare映射圖、譜圖、分岔圖等,分析了系統在定轉速及定的轉子系統參數下的運動
  18. Ds signal is twice modulated with the rapid pseudorandom noise sequence and the carrier. so it appears cyclostationary. in the field of spectral correlation, ds signals appears its characteristic as fallows : for the amplitude of spectral correlation, the information of carrier frequency and pn code rate are contained on the spectrum frequency equal to zero sheet, and also the pn code rate is contained on the sheet of spectrum frequency equal to carrier frequency ; for the phase of spectral correlation, the information of carrier initial phase is contained on the sheet of cyclic frequency equal to double carrier frequency

    Ds信號是經過高速偽隨機序列和正弦載波二調制的寬帶信號,因此具有周期平穩性,它在譜相關域表現為:幅性在譜率等於零截面切片上包含了載和偽碼速率信息,在譜率等於載截面切片上包含了偽碼速率信息;相性在循環率等於兩倍載截面切片上包含了載波初相信息
  19. Chapter three discusses the vibration information based automatic diagnosis mehtod. the acquisition of spectrum feature of fault pattern class by the fuzzy clustering algorithm is the bisis of pattern recognition in the level of fault class. the result acquired by fuzzy relationship between vibration symptom and fault shows the feature of fuzzy - relation - based method

    第三章主要研究基於振動信息的自動診斷方法,建立了故障模式類的概念,根據模糊聚類演算法確定了故障標準模式類及其,為在故障模式類層上的模式識別提供了理論基礎;研究了模糊關系診斷結果的分佈規律;建立了綜合診斷實現了基於綜合診斷方法的多機組、多測點在線診斷。
  20. High - frequency information after wavelet transform is a kind of one - time feature which is not convenient for pattern classification

    圖像小波變換后的高信息屬于小波變換的一
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