中国机械工程
中國機械工程
중국궤계공정
CHINA MECHANICAl ENGINEERING
2014年
13期
1795-1799
,共5页
任志英%高诚辉%林建兴%申丁
任誌英%高誠輝%林建興%申丁
임지영%고성휘%림건흥%신정
双树复小波变换%评定基准面%频带能量法%三维粗糙表面
雙樹複小波變換%評定基準麵%頻帶能量法%三維粗糙錶麵
쌍수복소파변환%평정기준면%빈대능량법%삼유조조표면
dual-tree complex wavelet transform (DT-CWT)%evaluation datum%band energy method%three-dimensional rough surface
针对目前用于提取三维粗糙表面基准面的第一和第二代小波存在的平移变动性与方向性差等缺点,以及最优小波基的选取和小波分解次数的确定等难点,提出将第三代小波变换---双树复小波变换(DT-CWT)用于三维粗糙表面的评定。通过比较三代小波实际重构图像以及仿真三维粗糙表面的误差和最大重构误差,得出了 DT-CWT 最优的结论;采用频带能量法确定 DT-CWT 的分解次数,并用仿真三维表面表征参数均方差 S 来验证得出的分解次数的正确性。最后用 DT-CWT 对具有分形特征的三维非平稳随机粗糙表面进行基准面的提取,结果验证了所提出方法的有效性。
針對目前用于提取三維粗糙錶麵基準麵的第一和第二代小波存在的平移變動性與方嚮性差等缺點,以及最優小波基的選取和小波分解次數的確定等難點,提齣將第三代小波變換---雙樹複小波變換(DT-CWT)用于三維粗糙錶麵的評定。通過比較三代小波實際重構圖像以及倣真三維粗糙錶麵的誤差和最大重構誤差,得齣瞭 DT-CWT 最優的結論;採用頻帶能量法確定 DT-CWT 的分解次數,併用倣真三維錶麵錶徵參數均方差 S 來驗證得齣的分解次數的正確性。最後用 DT-CWT 對具有分形特徵的三維非平穩隨機粗糙錶麵進行基準麵的提取,結果驗證瞭所提齣方法的有效性。
침대목전용우제취삼유조조표면기준면적제일화제이대소파존재적평이변동성여방향성차등결점,이급최우소파기적선취화소파분해차수적학정등난점,제출장제삼대소파변환---쌍수복소파변환(DT-CWT)용우삼유조조표면적평정。통과비교삼대소파실제중구도상이급방진삼유조조표면적오차화최대중구오차,득출료 DT-CWT 최우적결론;채용빈대능량법학정 DT-CWT 적분해차수,병용방진삼유표면표정삼수균방차 S 래험증득출적분해차수적정학성。최후용 DT-CWT 대구유분형특정적삼유비평은수궤조조표면진행기준면적제취,결과험증료소제출방법적유효성。
At present,wavelet transform applied to the establishment of three-dimensional rough surface datum was mainly the first and the second-generation wavelet.However,they had some de-fects such as the shift variation and poor directional selectivity and so on,especially the selection of optimum wavelet base and the determination of the times of wavelet decomposition,which was always the difficult points of surface evaluation.Now the third generation wavelet DT-CWT was used for val-uation of three-dimensional rough surfaces,by comparing the datum errors and maximum reconstruc-tion error of the actual reconstruction images of the three wavelets as well as simulation of three-di-mensional rough surface,the optimality of DT-CWT was obtained.Band energy method was em-ployed to ascertain the times of wavelet decomposition and then mean square error S which was the characterization parameter of three dimensional simulation surfaces was used to check the correctness of decomposition times.Finally,the reference surface of the three dimensional nonstationary random rough surface with fractal properties was extracted by DT-CWT transform.The results prove the ef-fectiveness.