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Abstrak :
ABSTRACT
Korban kanker dan tumor akut semakin bertambah tiap tahunnya dan menjadi salah satu penyebab kematian manusia terbanyak di dunia. Kanker dan tumor merupakan sel jaringan tubuh yang tumbuh secara abnormal dan merusak jaringan disekitarnya. Pada awalnya kanker dan tumor tidak memiliki gejala yang pasti pada stadium awal, dan bahkan dapat menyerang jaringan tubuh bagian dalam yang menyebabkan tidak bisa dilihat dengan mata manusia. Penyebab umum dari penderita kanker dan tumor akut adalah telatnya pendeteksian dini. Pendeteksian dini yang murah, proses yang cepat, sistem yang sederhana, dan alat yang portable menjadi salah satu solusi yang tepat untuk mengantisipasi perkembangan kanker ataupun tumor yang lebih jauh. Dari semua metode yang memiliki sistem perangkat keras yang murah, sederhana, dan portable yaitu metode microwave imaging. Algoritma yang paling sederhana dalam microwave imaging adalah Filtered Back Projection (FBP) dan Algebraic Reconstruction Technique (ART). Kedua metode tersebut akan dibandingkan dengan cara merekonstruksi citra phantom fisik buatan yang memiliki dua karakteristik dielektrik yang berbeda. Metode perbandingan kinerja yang dipakai terbagi menjadi dua, yaitu analisis kualitatif dan kuantitatif. Analisis perbandingan secara kualitatif meliputi kasar atau halusnya citra dan keberhasilan membedakan dielektrik secara kasat mata. Sedangkan metode kuantitatif meliputi metode Histogram, Structural Similarity, Mean Squared Error, dan Peak Signal-to-Noise Ratio. Setelah dibandingkan keduanya berhasil membedakan kedua dielektrik tetapi FBP memiliki nilai parameter analisis kuantitatif yang lebih baik dibandingkan ART. Di sisi lain ART menghasilkan citra yang lebih kontras dengan persebaran grayscale level yang lebih lebar dibandingkan FBP dan memperjelas citra yang dihasilkan.

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ABSTRACT
Victims of acute cancer and tumor are growing each year and just become one of the causes of human deaths in the world. Cancer and the tumor tissue cells are actually normal cells that grew abnormally and turn to take over and damage the surrounding tissue. At the beginning, cancer and tumors do not have definite symptoms in its early stages, and can even attack the tissues inside of the body that can not be seen with the human eye. Early detection system which is cheap, quick, simple, and portable is appropriate to anticipate the further development of cancer or tumor. Among all the methods that have a cheap, simple, and portable hardware system is microwave imaging methods. The two simplest algorithm in the microwave imaging are Filtered Back Projection (FBP) and Algebraic Reconstruction Technique (ART). Both of these methods will be compared by reconstructing the image of an artificial physical phantom that has two different dielectric value. Performance comparison method that has been used is divided into two method, namely qualitative and quantitative method. Qualitative comparative analysis covers the smoothness of an image and also the success in distinguishing dielectric value differences by looking the image with normal human eye. While quantitative method includes Histogram, Structural Similarity Index (SSIM), Mean Squared Error (MSE), and Peak Signal-to-Noise Ratio (PSNR). Having compared, their image results managed to distinguish the two dielectric, but in quantitative method FBP results are better than ART. On the qualitative method, ART produces more contrast image with wider distribution grayscale level than FBP, which is make the ART result image more distinguishable for each dielectric value.

Abstrak :
A two dimensional layer or cross section of a three dimensional object can be reconstructed by means of a large number of one dimensional projections through this layer. Reconstruction a two dimensional phantom from its one-dimensional projection has been accomplished in this thesis using the technique where the input projection data of CT X-Ray is simulated. The qualities of reconstructed phantom from the projections have shown a good result compared to the original image. This reconstruction technique has been implemented on PC and the reconstructed image is displayed using VGA monitor.

Abstrak :
Saat ini, komputasi tomografi (computed tomography/CT) sinar-X sudah banyak diterapkan di industri manufaktur untuk menguji atau memeriksa struktur internal suatu sampel. Metode Filtered Back Projecrtion (FBP) merupakan metode rekonstruksi citra CT yang popular digunakan untuk menghasilkan citra yang mempunyai noise lebih sedikit, kontras yang tajam dan mampu membedakan densitas antara latar belakang dan objek. Pemindaian citra digunakan mode geometri cone beam dengan rentang sudut 360° dan inkremen sudut 1°. Proses dimulai dari denoising, normalisasi, sintesis sinogram, dan rekonstruksi citra menggunakan FBP. Hasil dari penelitian ini adalah citra 2 dimensi hasil dari pemindaian citra geometri cone beam, sinogram dan hasil rekonstruksi citra irisan dengan parameter evaluasi yaitu Signal to Noise Ratio (SNR), Contrast to Noise Ratio (CNR), dan kontras relatif. Untuk mencari parameter evaluasi tersebut digunakan input koordinat Region of Interest (RoI). Diperoleh filter Cosine paling baik dalam memberikan nilai SNR, CNR dan kontras relatif paling tinggi. Dalam post processing akan digunakan variasi filter low pass (Ideal, Butterworth dan Gaussian). Input citra hasil rekonstruksi FBP menggunakan filter Cosine. Terdapat parameter evaluasi tambahan yaitu SSIM (Structural Similarity Index Measure). Beberapa parameter input seperti frekuensi cut-off, dan orde akan mempengaruhi frekuensi spasial. Frekuensi ini mengacu pada seberapa sering suatu gray value muncul atau berulang dalam citra. ......Currently, X-ray computational tomography (CT) has been widely applied in the manufacturing industry to test or examine the internal structure of a sample. The Filtered Back Projection (FBP) method is a popular CT image reconstruction method used to produce images that have less noise, sharp contrast and are able to distinguish densities between the background and the object. Image scanning uses the cone beam geometry mode with an angle range of 360° and an angle increment of 1°. The process starts from denoising, normalizing, sinogram synthesis, and image reconstruction using FBP. The results of this study are 2-dimensional images resulting from scanning geometric cone beam images, sinograms and reconstructed sliced images with evaluation parameters namely Signal to Noise Ratio (SNR), Contrast to Noise Ratio (CNR), and relative contrast. To find the evaluation parameters, the Region of Interest (RoI) coordinate input is used. The Cosine filter is the best in providing the highest SNR, CNR and relative contrvalues. In post processing, variations of low pass filters (Ideal, Butterworth and Gaussian) will be used. Input the FBP reconstruction image using the Cosine filter. There is an additional evaluation parameter, namely SSIM (Structural Similarity Index Measure). Several input parameters such as cut-off frequency, and order will affect the spatial frequency. This frequency refers to how often a gray value appears or repeats in the image.

Abstrak :
X-ray computed tomography (CT) has been playing an important role in current medical practice for diagnostic procedure. Beside its delicate technology, the 'hidden' software of CT image reconstruction has contributed almost half of total cost of a CT-scanner unit. Since Algebraic Reconstruction Technique (ART) is a basic to understand an iterative method of CT image reconstruction algortihm, and since it is difficult to find a clear description of fan beam ART algorithm in university literatures, it is important to develop an own algorithm and to begin a basic systematic research of this iterative method. After a long term of trial and error work, the research had succeded in developing an ART algorithm for third generation CT image reconstruction. By comparing the result of the research with more popular technique like Filtered Back Projection (FBP), the algorithm has been proved applicable to reconstruct a low dimension object matrix (32x32 and 64x64). By the resulted computer program, then basically a simple and low cost third generation CT-scanner can be designed for medical physics or biomedical imaging research. Finding a way of shortening the massive number of iterations process then, will be able to open the possibility of using the software for higher object matrix dimensions.