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Image Reconstruction by Filtered, Stochastic and Transform Based Techniques Using Parallel Beam Transmission Tomography

Thesis Info

Access Option

External Link

Author

Qureshi, Shahzad Ahmad

Program

PhD

Institute

Pakistan Institute of Engineering and Applied Sciences

City

Islamabad

Province

Islamabad.

Country

Pakistan

Thesis Completing Year

2009

Thesis Completion Status

Completed

Subject

Medical Image Processing

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/11304/1/PhD%20Thesis%20Shehzad%20Ahmed%20Qureshi.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726402392

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The image reconstruction by parallel ray transmission tomography has been carried out by using filtered, stochastic and transform-based techniques. Image quality has been analyzed by various error measures using Filtered Back-Projection (FBP) technique with various composite filters, namely Shepp-Logan, Cosine and Hamming filters. The effect of projections on filtered-based image reconstruction has also been thoroughly investigated. A stochastic-based, Hybrid Simulated Annealing (HSA) algorithm has been proposed for the image reconstruction using lesser number of projections or when the data is missing or corrupt. Various parameters have been tuned including generic parameters, like initial and final temperatures, annealing schedule, slab-thickness with constant temperature, etc. along with problem specific parameters, like size and structure complexities, number of projections, etc. The image quality has been compared with other techniques, namely FBP and Algebraic Reconstruction Technique (ART). Another stochastic algorithm, the Hybrid Continuous Genetic Algorithm (HCGA), has also been introduced for image reconstruction. It has been used with preprocessed image data or even the actual human data for image reconstruction. The templates used were of two types: the FBP-based and the multiscale Wavelet Transform based. Various operators, namely Mixed Selection Scheme, Image Row Crossover operator, Offset Based Mutation and Hybrid Diversification operators have been introduced. The sensitivity analysis of various selection schemes, like truncation, roulette wheel, tournament selection, etc., crossover schemes, like single point, multi point, uniform crossover schemes, etc., and mutation schemes, namely standard- and gradient-based schemes, have been investigated in depth for tomographic image reconstruction. The number of projections has been optimized for HCGA reconstruction to p = 30. The HCGA-based image reconstruction for 8 × 8 to 128 × 128 sized images have been found to be better than FBP and ART techniques, and even better relatively for larger image sizes than the HSA. The fitness function analysis has also been carried out for various functions like Root Mean Squared error (RMSE), Mean Squared error (MSE), Mean Absolute error (MAE), Relative Squared error (RSE), Root Relative Squared error (RRSE), etc. The MAE and RMSE have been generally found to converge relatively in shorter times in comparison to the rest of the functions under consideration. The HDO introduction in the Evolution cycle, using the SA and the decreasing law of mutation probability, culminated to relatively more promising results. The essence of this thesis is the relative comparison of various stochastic techniques by using filtered and transform-based techniques for the first time in the field of parallel ray transmission tomography. The work is exhaustive, multi-dimensional with conclusive results.
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حدیثِ خواب گویم

حدیثِ خواب گویم
سفر نامے کے بنیادی لوازمات میں سے ایک سفر بھی ہے ۔جب کہ اس میں برتی جانے والی پابندیوں میں سب سے اہم فسوں گری اور مبالغے سے اجتناب ہے۔ یہ لوازمات اور پابندیاں کسی اور ملک کے سفر پر نکلے سفر نامہ نگار کے لیے زیادہ مشکل نہ ہوں مگر سفر اگر مصر کا ہو تو سفر نامہ نگار کے لیے یہ دو دھاری تلوار پر چلنے سے کم نہیں۔
مصری تہذیب کی حقیقت جس قدر مسلمہ ہے اس قدر فسوں آمیز۔ یہاں کے نظارے اس حد تک تحیر آمیز ہیں کہ ان پر بات کرنی اور اس پر تحریر کرتے وقت طلسماتی ارتعاش اور فینتاسی سے خود کو الگ کرنا ممکن ہی نہیں ہوتا۔
فوق الفطری ماحول اور فضا، قصہ در قصہ بنیادی حقیقت اور واقعے کے ساتھ ضمنی کہانیاں ،غیر مرئی حقیقت ،انسانوں کے علاوہ جانوروں اور چرند پرند سے منسلک واقعات، مرکزی کرداروں کی غیر معمولی طاقت اور حیثیت ،معاون کرداروں کی فوجِ ظفر موج، مشکلات، رکاوٹوں کاذکر، مذہبی اور دینی عقاید و تجربات ،آسمانی اور انسانی قوانین کا ذکر اور نفاذ غرض وہ تمام لوازمات جو کسی افسانوی تحریر کے خاصے ہوتے ہیں ، مصر پر لکھے سفر نامے کے بنیادی شرائط و لوازم بن جاتے ہیں۔
ان ہی لوازمات کی وجہ سے سفر نامہ داستان اور فسوں گری کا لبادہ اوڑھ لیتا ہے۔ لکھاری تہذیبی، تاریخی اور ذاتی داخلیت کا شکار ہو جاتا ہے۔ مسافر کے ساتھ بھی اس سفر پر کچھ ایسا ہی ہوا۔ جہاں بھی گیا حقیقتیں، حسین تخیل اور سچائیاں فینتاسی کا روپ دھار لیتیں، چاہے یہ حقیقتیں فراعینِ مصر کی ہوں یا یہ سچائیاں وادیٔ سینا کی طلسماتی فضا کی ہوں جہاں ریب و تکذیب کی گنجائش نہ ہوتے ہوئے بھی میری فکر افسوں اور بالعکس فسوں کے ساتھ ابہام و سحر کی خواب...

اسلام اور سائنس میں تضاد کا تحقیقی جائزہ

This research is intended to explore the nature of relationship between Islam and Science whether they are compatible with each other or not? By studying and comparing the teachings of Islam and science it has been exposed that both are different in their foundations, nature and scope. Domain of science is limited to the realm of senses whereas Islam provides the knowledge and guidance about materialistic, unseen and metaphysical domain. Foundations of religion are based upon the revelation while science is based upon theories and experiments. Therefore when science reach the reality after passing through trial and error, confirms the teachings of religion, which proves that Islam and science are not only compatible but Islam plays a role of leadership and basic source for the scientific investigations. Moreover after careful review of Islamic and scientific knowledge it is suggested to know the foundations, nature and scope of both to know the relationship between them and to avoid the confusion.

Biosorptive Potential and Binding Sites of Heavy Metals on the Cell Wall of Selected Filamentous Algae

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