以賑f轉換作為前處理的去雜訊方法來改善平均間距估測

Using Gabor Transform and denoising as preprocess for improvement of mean scatterer spacing estimator

趙復慷(CHAO FU KANG)

指導教授 ： 曹建和

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.10153

摘要

肝硬化在台灣是十分常見的疾病，利用超音波診斷肝硬化是醫師最常使用的方式之一，但因受檢者生理上結構的不同，以及不同的醫師有不同主觀上的判斷，導致人為誤診的機率大為增加。本研究為應用誧B轉換分析進行正常肝和肝硬化這二類的辨識，論文中首先對於誧B轉換做一概略性的介紹，接著進一步利用誧B轉換將由超音波儀器所取得的超音波訊號計算平均間距估測，最後用一模擬實驗來比較經過誧B轉換並去雜訊和未經處理訊號的不同以及改善的程度。此種辨識方法可成為輔助醫生診斷肝硬化的一個依據，進而使人為誤診的機率降低。

關鍵字

平均間距估測 ； 最佳化間隔 ； 誧B轉換

並列摘要

Liver Cirrhosis is a very popular disease in Taiwan. Utilizing ultrasound to diagnose Cirrhosis is one of the most frequently used methods by the doctors, but patients have different physiology structure and doctors also have some different subjective judgments, therefore contrived mistake is increased in diagnosis probability.
This research is to apply Gabor Transform and denoising to classify two cases between Cirrhosis and normal liver. In this research, I firstly introduce a summary to Gabor transform, and secondly by means of Gabor Transform and denoising to calculate mean scatterer Spacing in a supersonic diagnostic set to get ultrasound signals. Finally, to point out that what has been improved by Gabor transform and denoising. This classified method is an assistance for doctors to diagnose Cirrhosis, so as to reduce man-made mistake in diagnosis probability.

並列關鍵字

Gabor Transform ； Mean Scatterer Sp ； Optimal Sampling

參考文獻

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