Computed Tomography or CAT Scans/Data Acqusition


         My question is regarding DAQ card.If IR transmitter and receiver and placed opposite to each other.Emitter emits IR and receiver collect them ,my question is that how receiver recognize whether these rays passed from phantom or they just directly reaches receiver.
And my second question is that ,What are the changes in IR behaviour when they passed from phantom or transparent material.   
         Regards Mazhar Ali

The voltage level or the current measured would let us know the intensity of light transmitted. The IR through phantom would certainly be absorbed or consumed to some extent. In comparison to this the IR reaching directly to the photo-detector would be creating a strong output signal to the acquisition system.
The IR is prone to phenomena known for visible light as the latter being lying next to the visible light in the wavelength chart. The refraction is suffered by IR even if it passes through the air. This slowness of IR velocity varies with the material in hand.


Dr. Shahzad.  

Computed Tomography or CAT Scans

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Dr. Shahzad Ahmad Qureshi


I can answer questions about transmission computed tomography, simulated annealing-based tomography and binary & continuous genetic algorithms-based tomography. I shall not be able to answer as an expert about MRI, fMRI...


I have an eight year experience as a researcher.

National Institute of Lasers and Optronics, Islamabad, Pakistan.


1. S. A. Qureshi, S. M. Mirza, Nasir M. Rajpoot, Member IEEE, and M. Arif A Novel GA Approach to Tomographic Image Reconstruction, IEEE Trans. Image Processing, Vol. 20, Issue 7, pp. 1977-1990, 2011 (Online ISSN: 1057-7149, DOI: 10.1109/TIP.2011.2107328) ISI index: 4.205, 2011

2. S. A. Qureshi, S. M. Mirza, and M. Arif Hybrid Simulated Annealing Image Reconstruction for Parallel-Ray Transmission Tomography, Inverse Problems in Science and Engineering, Taylor & Francis, Vol. 17, Issue 5, pp. 647-664, 2009 (Online ISSN: 1741–5985, Print ISSN: 1741–5977, DOI: 10.1080/17415970802390085) ISI index: 0.416, 2008

3. S. A. Qureshi, S. M. Mirza, and M. Arif Determination of Optimal Number of Projections and Parametric Sensitivity Analysis of Operators for Parallel-Ray Transmission Tomography using Hybrid Continuous Genetic Algorithm, International Journal of Imaging Systems and Technology, Vol. 17, Issue 1, pp. 10-21, 2007 (Online ISSN: 1098-1098, Print ISSN: 0899-9457, DOI: 10.1002/ima.20093), ISI index: 0.983, 2006

4. S. A. Qureshi, S. M. Mirza, and M. Arif Optimization of Projections for Parallel-Ray Transmission Tomography using Genetic Algorithm, in Wireless Networks, Information Processing and Systems, Vol. 20, Issue 3, pp. 20-39, 2006, Springer Berlin Heidelberg, 2008 (Online ISSN: 1865-0929, Print ISSN: 1865-0937, Online ISBN: 978-3-540-89852-8, Print ISBN: 978-3-540-89853-5, DOI: 10.1007/978-3-540-89853-5_6)


PhD (Computer Science), MS (Nuclear Engg.), MSc (Computer Science), BE (Metallurgical Engg. and Materials Science)

Awards and Honors

• Fellowship for Ph.D. in Computer Science by Higher Education Commission, Islamabad (2004).

• Fellowship for Research Work at the University of Warwick, the United Kingdom during PhD in the Image Processing Group at the Department of Computer Science (2008)

• Fellowship for M.Sc. Nuclear Engineering from Quaid-i-Azam University, Islamabad for the session 1994-96

• University Merit Scholarship by UET, Lahore awarded every year for being declared as the Top Student during BE

• Gold Medalist of BE with HONOURS by UET, Lahore for the session 1988-92

• Secured Bull’s Eye (100% score) in TCP/IP 4.0 and 90% in Networking Essentials and Microsoft Windows NT 4.0 Workstation (MCSE)

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