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"Penelitian ini menggunakan metode ambient noise tomography (ANT) untuk mengidentifikasi kondisi bawah permukaan di wilayah Cekungan Bandung. Data penelitian adalah seimic waveform yang terekam pada 15 stasiun, berasal dari gempa yang terjadi dari Januari 2022 hingga Juli 2022. Metodologi penelitian meliputi persiapan data tunggal, korelasi silang dan stacking, picking kurva dispersi, uji resolusi, pembuatan peta kecepatan grup gelombang Rayleigh, dan analisis hasil. Hasil yang diperoleh berupa peta distribusi kecepatan grup gelombang Rayleigh dengan periode antara 3 hingga 32 detik. Dari penelitian ini, didapatkan hasil bahwa pemodelan tomografi kecepatan gelombang Rayleigh di wilayah Cekungan Bandung dengan menggunakan metode ambient noise tomography menunjukkan variasi kecepatan grup antara 0,1 km/s hingga 3,5 km/s. Distribusi kecepatan gelombang Rayleigh pada hasil tomogram secara jelas mengidentifikasi beberapa struktur geologi seperti litologi batuan penyusun dan cekungan di wilayah tersebut. Penelitian juga menemukan adanya zona kecepatan rendah yang mencapai 18 detik, yang mengindikasikan keberadaan sedimentasi lapisan lunak yang sangat dalam dengan wilayah cakupan yang luas. Hasil penelitian ini menunjukkan bahwa metode ambient noise tomography efektif dalam mengidentifikasi model kecepatan grup gelombang bawah permukaan, memberikan wawasan mendalam tentang struktur geologi di Cekungan Bandung.

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This study utilizes the ambient noise tomography (ANT) method to identify subsurface conditions in the Bandung Basin area. The research data consists of seismic waveforms recorded at 15 stations, originating from earthquakes occurring between January 2022 and July 2022. The research methodology includes single data preparation, cross-correlation and stacking, dispersion curve picking, resolution testing, Rayleigh wave group velocity mapping, and result analysis. The results obtained are in the form of a Rayleigh wave group velocity distribution map with periods ranging from 3 to 32 seconds. The study found that the Rayleigh wave velocity tomography modeling in the Bandung Basin area using the Ambient noise tomography method shows a group velocity variation between 0.1 km/s and 3.5 km/s. The distribution of Rayleigh wave velocities on the tomogram results clearly identifies several geological structures such as the composing rock lithology and the basin in the area. The study also identified a low-velocity zone reaching 18 seconds, indicating the presence of very deep and extensive soft sediment layers. These findings demonstrate that the Ambient noise tomography method is effective in identifying the subsurface Rayleigh wave group velocity model, providing in-depth insights into the geological structure of the Bandung Basin."

"Teknik Cone Beam Computed Tomography (CBCT) dalam pemindaian 3DRA menggunakan sinar-X berbentuk kerucut bulat atau persegi panjang dengan rotasi pemindaian yang tidak mencapai 360 derajat. Sementara itu, metode perhitungan dosimetri 3DRA saat ini masih mengacu pada konsep CTDI, hal ini mungkin tidak sesuai untuk dosimetri CBCT karena sudut pancaran cone yang lebih besar dibandingkan dengan sudut pancaran fan beam dan rotasi pemindaian 3DRA yang tidak mencapai 360 derajat. Penelitian ini bertujuan untuk menganalisis distribusi dosis pada simulasi dan pengukuran dalam pemindaian Angiografi Rotasi Tiga Dimensi (3DRA). Metode yang digunakan melibatkan perbandingan hasil simulasi distribusi dosis menggunakan perangkat lunak EGSnrc dengan hasil pengukuran pada pesawat Angiografi Phillips Allura FD20 (tiga mode pemindaian) menggunakan bilik ionisasi. Proses simulasi menggunakan perangkat lunak EGSnrc terdiri dari tiga tahap. Pertama, lima fantom CTDI virtual dibuat untuk merepresentasikan lubang sesuai dengan penempatan dosimeter pada posisi yang berbeda (pusat, arah jam 3, 6, 9, dan 12). Ukuran voxel fantom disesuaikan menjadi 1 × 1 × 1 mm². Tahap kedua melibatkan pemodelan dan simulasi tabung sinar-X pada sistem 3DRA menggunakan perangkat lunak BEAMnrc. Terakhir, dilakukan simulasi penyinaran pada fantom virtual menggunakan perangkat lunak DOSXYZnrc. Jumlah histories untuk simulasi ditetapkan menjadi 2.5×108, nilai energi cutoff diatur pada 0,521 MeV untuk transportasi elektron, dan 0,001 MeV untuk transportasi foton. Hasil penelitian menunjukkan bahwa area yang paling banyak terpapar radiasi pada ketiga mode 3DRA terletak pada arah jam 3, 6, dan 9 dari fantom. Nilai akurasi tertinggi didapatkan pada mode Xper CT Cerebral HD pada posisi pengukuran pusat dengan nilai presentase perbandingan sebesar 0,9%, sementara nilai akurasi terendah didapatkan pada mode Xper CT Cerebral LD pada posisi pengukuran arah jam 6 dengan nilai prensentase perbandingan sebesar 647,3%.

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Cone Beam Computed Tomography (CBCT) in 3D rotational angiography (3DRA) uses cone-shaped X-ray beams with non-360 degrees rotation. However, current dosimetry calculation methods for 3DRA, which are based on CTDI formalism, may not be suitable due to the larger cone beam angles compared to fan beam angles and the rotation of 3DRA being not a full 360-degree rotation. This study aims to analyze the dose distributions in simulations and direct measurements in 3DRA scans. The method involves comparing the simulation results of dose distributions using EGSnrc software with direct measurements Philips Allura FD20 angiography (in three preset modes) using a head CTDI phantom and an ionization chamber. To analyze the dose distributions in 3DRA, five virtual CTDI phantoms are generated to represent holes corresponding to the placement of dosimeters at different positions (at center, 3, 6, 9, and 12 o'clock). The voxel size of the phantoms is adjusted to 1×1×1 mm². The modeling and simulation of the X-ray tube in the 3DRA system using the BEAMnrc software. The DOSXYZnrc software is used to simulate the irradiation on the virtual phantom. The simulation is performed with 2.5×108 histories, and the energy cutoff value is set at 0.512 MeV for electron transport and 0.001 MeV for photon transport. The results show that the areas most exposed to radiation in all three preset modes of 3DRA are located on the sides and bottom (at 3, 6, and 9 o'clock) of the phantom. The highest accuracy value was obtained in the Xper CT Cerebral HD mode at the center position with a percentage comparison value of 0.9%, while the lowest accuracy value was obtained in the Xper CT Cerebral LD mode at the 6 o'clock position with a percentage comparison value of 647.3%."

"Technology and principles using cone beam computed tomography / Matthew Jacobson -- The nature of ionizing radiation and the risks from maxillofacial cone beam computed tomography / Sanjay M. Mallya and Stuart C. White -- Diagnosis of jaw pathologies using cone beam computed tomography / Sharon Brooks -- Diagnosis of sinus pathologies using cone beam computed tomography / Aaron Miracle and Christian GuÌ?ldner -- Orthodontic and orthognathic planning using cone beam computed tomography / Lucia H.S. Cevidanes, Martin Styner, Beatriz Paniagua, JoaÌ?o Roberto Gonçalves -- Three-dimensional planning in maxillofacial reconstruction of large defects using cone beam computed tomography / Rutger Schepers, Gerry M. Raghoebar, Lars U. Lahoda, Harry Reintsema, Arjan Vissink, and Max J. Witjes -- Implant planning using cone beam computed tomography / David Sarment -- CAD/CAM surgical guidance using cone beam computed tomography / George A. Mandelaris and Alan L. Rosenfeld -- Assessment of the airway and supporting structures using cone beam computed tomography / David D. Hatcher -- Endodontics using cone beam computed tomography / Martin D. Levin -- Periodontal disease using cone beam computer tomography / Bart Vandenbergh"

"Over the past decade, PET-CT has achieved great success owing to its ability to simultaneously image structure and function, and show how the two are related. More recently, PET-MRI has also been developed, and it represents an exciting novel option that promises to have applications in oncology as well as neurology. The first part of this book discusses the basics of these dual-modality techniques, including the scanners themselves, radiotracers, scan performance, quantitation, and scan interpretation. As a result, the reader will learn how to perform the techniques to maximum benefit. The second part of the book then presents in detail the PET-CT and PET-MRI findings in cancers of the different body systems. The final two chapters address the use of PET/CT in radiotherapy planning and examine areas of controversy. The authors are world-renowned experts from North America, Europe, and Australia, and the lucid text is complemented by numerous high-quality illustrations."

"Computed tomography (CT) is a powerful technique providing precise and confident diagnoses. The burgeoning use of CT has resulted in an exponential increase in collective radiation dose to the population. Despite investigations supporting the use of lower radiation doses, surveys highlight the lack of proper understanding of CT parameters that affect radiation dose. Dynamic advances in CT technology also make it important to explain the latest dose-saving strategies in an easy-to-comprehend manner. This book aims to review all aspects of the radiation dose from CT and to provide simple rules and tricks for radiologists and radiographers that will assist in the appropriate use of CT technique. The second edition includes a number of new chapters on the most up-to-date strategies and technologies for radiation dose reduction while updating the outstanding contents of the first edition. Vendor perspectives are included, and an online image gallery will also be available to readers."

"This book provides a lucid summary of modern multislice CT imaging of the abdomen, with a focus on the essential imaging findings. After a concise technical introduction, the most important abdominal diseases are described and illustrated with high-quality images. Sections are devoted to the liver and biliary system, the pancreas and spleen, the kidneys and urogenital system, and the bowel and peritoneal cavity. Throughout, key differential diagnostic features are highlighted. The editorial team is composed of internationally renowned radiologists from Europe and the United States, and all chapters have been written by recognized experts in the topic under consideration. Multislice CT of the Abdomen will serve as an excellent reference for radiologists participating in further professional training and will prove an ideal source of information for all who wish to deepen their personal knowledge of the subject."