◎林道通老師與劉萬榮老師之升等教師公開發表會議◎

  • 國立臺北大學 電機工程學系
  • 六月 6, 2009

電機資訊學院-資訊工程系
公開發表教師:林道通教師
公開發表時間:12:00~12:40
公開發表著作: Computer-Aided Kidney Segmentation on Abdominal CT Images.Abstract
In this talk, an effective model-based approach for computer-aided kidney segmentation of abdominal CT images with anatomic structure consideration is presented. This automatic segmentation system is expected to assist physicians in both clinical diagnosis and educational training. The proposed method is a coarse-to-fine segmentation approach divided into two stages. First, the candidate kidney region is extracted according to the statistical geometric location of kidney within the abdomen. This approach is applicable to images of different sizes by using the relative distance of the kidney region to the spine. The second stage identifies the kidney by a series of image processing operations. The main elements of the proposed system are: 1) the location of the spine is used as the landmark for coordinate references; 2) elliptic candidate kidney region extraction with progressive positioning on the consecutive CT images; 3) novel directional model for a more reliable kidney region seed point identification; and 4) adaptive region growing controlled by the properties of image homogeneity. In addition, in order to provide different views for the physicians, we have implemented a visualization tool that will automatically show the renal contour through the method of second-order neighborhood edge detection. We considered segmentation of kidney regions from CT scans that contain pathologies in clinical practice. The results of a series of tests on 358 images from 30 patients indicate an average correlation coefficient of up to 88% between automatic and manual segmentation.
電機資訊學院-電機工程研究所
公開發表教師:劉萬榮老師
公開發表時間:12:40~13:20
公開發表著作:A High Efficiency Dual-Mode Buck Converter IC For Portable Applications
Abstract
This talk presents the design of a novel wide output current range dual-mode DC to DC step-down (Buck) switching regulator/converter. The converter can adaptively switch between pulse-width modulation (PWM) and pulse-frequency modulation (PFM) both with very high conversion efficiency. Under light load condition the converter enters pulse-frequency-modulation mode. The function of closing internal idle circuits is implemented to save unnecessary switching losses. The converter can be switched to pulse-width modulation mode when the load current is greater than 100 mA. Soft start operation is designed to eliminate the excess large current at the start up of the regulator. The chip has been fabricated with a TSMC 2P4M 0.35 μm polycide CMOS process. The range of the operation voltage is from 2.7 V to 5 V, which is suitable for single-cell lithium-ion battery supply applications. The maximum conversion efficiency is 95% at 50 mA load current. Above 85 % conversion efficiency can be reached for load current from 3 to 460 mA.