本文選題：太赫茲無損檢測(cè) + 小波變換�。� 參考：《華中科技大學(xué)》2015年碩士論文

【摘要】：本論文主要提出并檢驗(yàn)了一種通過太赫茲波來分析樣品內(nèi)部缺陷的方法。這種方法能夠通過工程數(shù)學(xué)來處理樣品的太赫茲波三維掃描數(shù)據(jù),然后得到樣品的內(nèi)部缺陷情況,如樣品內(nèi)缺陷的大小和分布,并具有廣泛的適用范圍。全文從理論研究、實(shí)驗(yàn)設(shè)計(jì)和實(shí)驗(yàn)結(jié)果分析三個(gè)方面對(duì)這種方法進(jìn)行了描述。其中,小波變換理論和利普希茨連續(xù)條件理論是這種方法的理論基礎(chǔ)。小波變換的時(shí)頻分析手段非常適合于提取這種由缺陷造成的小范圍突變信號(hào),同時(shí),由利普希茨連續(xù)條件產(chǎn)生的指數(shù)工具能很好的描述突變信號(hào)的變化快慢和程度。因此,在小波變換的基礎(chǔ)上利用利普希茨指數(shù)衡量樣品的內(nèi)部缺陷情況能獲得很好的效果。為了對(duì)缺陷狀況進(jìn)行最直觀的描述,本論文根據(jù)利普希茨指數(shù)的統(tǒng)計(jì)規(guī)律設(shè)計(jì)了一個(gè)權(quán)值,用來衡量樣品內(nèi)的某一區(qū)域是缺陷的可能性。本論文設(shè)計(jì)了一系列實(shí)驗(yàn)來驗(yàn)證這種方法的有效性,并嚴(yán)謹(jǐn)?shù)倪M(jìn)行了樣件準(zhǔn)備、儀器選擇以及算法設(shè)計(jì)等過程,實(shí)驗(yàn)中的一些比較重要的參數(shù)都是通過進(jìn)行多次對(duì)比實(shí)驗(yàn)的方式而決定的。整個(gè)實(shí)驗(yàn)過程是在盡量模擬實(shí)際狀況的原則下進(jìn)行的,力求實(shí)驗(yàn)結(jié)果具有代表性。在進(jìn)行了簡(jiǎn)單的處理之后,本論文對(duì)實(shí)驗(yàn)結(jié)果進(jìn)行了全面分析。實(shí)驗(yàn)結(jié)果表明,這種方法能從一定程度上反映出樣品內(nèi)部的缺陷情況,并具有較大的可靠程度,同時(shí)還能自由的調(diào)節(jié)判斷標(biāo)準(zhǔn)的嚴(yán)格程度。
[Abstract]:In this paper, we propose and test a method to analyze the internal defects of samples by terahertz wave. This method can process the terahertz wave 3D scanning data of samples by engineering mathematics, and then obtain the internal defects of the samples, such as the size and distribution of the defects in the samples, and have a wide range of application. This method is described from three aspects: theoretical research, experimental design and analysis of experimental results. Wavelet transform theory and Lipschitz continuous condition theory are the theoretical basis of this method. The time-frequency analysis method based on wavelet transform is very suitable for extracting the small range abrupt signal caused by the defect. At the same time, the exponential tool produced by Lipschitz continuity condition can describe the change speed and degree of the abrupt change signal very well. Therefore, on the basis of wavelet transform, using Lipschitz index to measure the internal defects of samples can obtain good results. In order to describe the defect state intuitively, this paper designs a weight value according to the statistical law of Lipschitz index, which is used to measure the possibility that a certain region in the sample is a defect. In this paper, a series of experiments are designed to verify the effectiveness of this method, and the process of sample preparation, instrument selection and algorithm design are carefully carried out. Some of the more important parameters in the experiment are determined by several comparative experiments. The whole experiment process is carried out under the principle of simulating the actual situation as far as possible, and the experimental results are representative. After a simple treatment, the experimental results are analyzed comprehensively in this paper. The experimental results show that this method can reflect the defects in the sample to a certain extent and has a greater degree of reliability. At the same time, it can freely adjust the strict degree of the judgment standard.
【學(xué)位授予單位】：華中科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：O441.4

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 楊勇;郭吉強(qiáng);;Lipschitz指數(shù)與平穩(wěn)小波變換在CT圖像去噪中的應(yīng)用[J];計(jì)算機(jī)工程與應(yīng)用;2012年06期

2 戴建新;酈志新;宋洪雪;;基于小波的信號(hào)Lipschitz指數(shù)分析和應(yīng)用[J];南京郵電大學(xué)學(xué)報(bào)(自然科學(xué)版);2008年06期

3 余付平;朱榮新;王韞江;李斌;丁克勤;;脈沖渦流檢測(cè)技術(shù)的研究進(jìn)展和展望[J];無損檢測(cè);2008年11期

4 張?chǎng)?雷銀照;;太赫茲無損檢測(cè)的進(jìn)展[J];儀器儀表學(xué)報(bào);2008年07期

5 王明紅;薛謙忠;劉濮鯤;;太赫茲真空電子器件的研究現(xiàn)狀及其發(fā)展評(píng)述[J];電子與信息學(xué)報(bào);2008年07期

6 張德豐;;基于小波的信號(hào)突變點(diǎn)檢測(cè)算法研究[J];計(jì)算機(jī)工程與科學(xué);2007年12期

7 孫博;姚建銓;;基于光學(xué)方法的太赫茲輻射源[J];中國(guó)激光;2006年10期

8 廖錦翔,袁明武;結(jié)構(gòu)裂縫群的小波方法識(shí)別和數(shù)值模擬[J];華南理工大學(xué)學(xué)報(bào)(自然科學(xué)版);2005年02期

9 任偉建,康朝海,于鏑,張正輝;小波變換在信號(hào)奇異性檢測(cè)中的應(yīng)用[J];自動(dòng)化技術(shù)與應(yīng)用;2005年01期

10 龍興明,周靜;連續(xù)小波變換的一維信號(hào)檢測(cè)[J];重慶郵電學(xué)院學(xué)報(bào)(自然科學(xué)版);2004年03期

，

本文編號(hào)：1897448