Dissertation > Excellent graduate degree dissertation topics show

Open Three-dimensional Multi-frequency Impedance Measurement System

Author: JuKang
Tutor: HeWei
School: Chongqing University
Course: Electrical Engineering
Keywords: Electrical impedance tomography three-dimension multi-frequency
CLC: R318.0
Type: Master's thesis
Year: 2011
Downloads: 31
Quote: 0
Read: Download Dissertation

Abstract


Breast disease is a common disease of women. With the continuing increase in incidence of breast cancer, it has become a major threat against women’s health. Because the pathogenesis of breast cancer is not clear, early detection and timely treatment is the key to reducing mortality. Generally speaking, the beginning of disease is functional failure, then is morphological changes. Common medical imaging techniques can only detect morphological changes, but functional medical imaging technology can detect functional failure.Electrical impedance tomography(EIT) is a functional medical imaging technology in recent years. It injects a safe electric excitation and measures the electrical response by electrodes around the skin, to reconstruct the conductivity distribution within the body. The advantages of EIT include: noninvasive, inexpensive, and so on. But because of limited information and ill-conditioned algorithm, the resolution of EIT is restricted. EIT is considered to be an adjunct to early disease detection and continuous monitoring method.In this paper, a open three-dimensional multi-frequency impedance measurement system is studied to detect human breast disease. It analyses breast tissue under electric excitation at different frequencies and the mathematical model of EIT, designs EIT measurement system and built experimental platform to measure the parameters of this system. Mainly to do the following:(1)It analyzed lesion tissue with different electrical characteristics of normal tissue, Specific to normal breast tissue and cancerous tissue under electric excitation at different frequencies. And the mathematical model of EIT was deduced.(2)To enlarge the limited information of two-dimensional EIT, it designed three-dimensional EIT of 64 electrodes. 8*8 electrode array was designed for breast, and a complex back electrode was selected by use of discrimination norm. Four-electrode measurement was chose.(3)It used two kinds of incentives: sweeping method and mixing method. Two methods were based on direct digital frequency synthesis, by use of field programmable gate array.(4)To demodulate signal, it studied two demodulations: digital phase sensitivity detection and fast Fourier transform. (5)It designed circuits to measure the current source’s output current, impedance and output voltage. It also studied the power supply module, communication module.(6)It measured the current source’s impedance and the spectrum of mixing frequency. Set a resist network as the load, to get relative precision of the system. By use of agar, a experiment is finished, and preliminary imaging result was obtained.

Related Dissertations

  1. Multi-frequence Weak Signal Acquisition and Processing System Research and Design,TN911.23
  2. Microstrip miniaturized multi-band -pass filter design,TN713.5
  3. Electrical impedance tomography system excitation circuit design,TH776
  4. A Study on Processing and Application of GPS Muti-Frequency Observations Data,P228.4
  5. Study on the Preparation of Flavor Substances in Garlic by Multi-frequency Ultrasound Coupled with Endo-enzymatic Hydrolysis,TS264.3
  6. The Study of Multiple-frequency Ultrasound Assisted Leaching Curcumin from Turmeric,TQ611.3
  7. System Simulation and Analysis of Hydraulic Excavator’s Working Device,TU621
  8. Study on the Fault Diagnosis of Asynchronous Induction Motor Base on the Wavelet Analysis,TH165.3
  9. Meridian study magnetic detection electrical impedance tomography,R224.1
  10. Research and Application of 3D Surface Measurement Technology Based on Multiple Frequency Phase-shift Technology of Structured Light,TP391.41
  11. Research on Image Reconstruction Algorithm Based on Medical Electrical Impedance Tomography,TP391.41
  12. The Voice Gateway Signal Processing Based on ARM,TN916.2
  13. The remuneration design study of Yantai International Marine Shipping Company,F272.92
  14. The Research and Application of 3D Editing Technology of DLG,P231.5
  15. Numerical Simulation of Bubbling Dynamics in Gas-Liquid Columns with Volume of Fluid Method,O359.1
  16. Research on Phase Determining in Frequency Domain for Multisine Signals,TM935.2
  17. Analysis of Stress-strain on Kensiwate Concrete Face Rock-fill Dam,TV641.43
  18. The Research and Optimization of PET Image Reconstruction Algorithm,TP391.41
  19. Three Dimensional Face Recognition for Template Protection Technology,TP391.41
  20. Research on the Control Strategy of Active Power Filter Based on Four-Leg Voltage-Source Inverters,TN713.8

CLC: > Medicine, health > Basic Medical > Medical science in general > Biomedical Engineering > General issues
© 2012 www.DissertationTopic.Net  Mobile