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ANALISIS NILAI COMPUTED TOMOGRAPHY DOSE INDEX (CTDI) PHANTOM KEPALA MENGGUNAKAN CT DOSE PROFILER DENGAN VARIASI PITCH Sari, Devi Artika; Setiawati, Evi; Arifin, Zaenal
BERKALA FISIKA Vol 23, No 2 (2020): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

The purpose of this study was to measure the value of computed tomography dose index (CTDI) using the CT dose profiler, to compare the values of CTDI obtained in the five holes within the head of polymethil-methacrylate (PMMA) phantom, and to analyze the effect of pitch on CTDI values. The CTDI values were measured with the pitch variations of 0.562, 0.938, 1.375, and 1.750. The phantom was scanned with fixed parameters of 120 kVp, 200 mAs, 10 mm width collimation, 150 mm scan length, and 0.50 s tube rotation. Measurements were conducted at Kensaras hospital using the CT scannner of GE Optima CT580 16 slice. The results showed that if the pitch increases, the CTDI will decrease (< 25 mGy). The highest CTDI is 55,36 mGy and it is found on a pitch of 0,562 at upper hole of phantom (B position), and the lowest CTDI is 11,9 mGy and it is found a pitch of pitch 1,750 within a hole at three o’clock position (C position). If the pitch < 1, then the high CTDI is obtained (> 50 mGy) and it takes longer to scan.
STUDI PRODUKSI RADIONUKLIDA MEDIS UNTUK GENERATOR 89Sr/90Y DARI HASIL REAKSI 89Rb(p,n)89Sr/90Y PADA SIKLOTRON MEDIK SECARA KOMPUTASI Hidayat, Yusup; Wardaya, Asep Yoyo; Triadyaksa, Pandji; Setiawati, Evi; Muhlisin, Zaenul; Sumariyah, Sumariyah; Suseno, Jatmiko Endro; Binu Soesanto, Qidir Maulana
BERKALA FISIKA Vol 22, No 4 (2019): Berkala Fisika Vol. 22 No. 4 Tahun 2019
Publisher : BERKALA FISIKA

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Abstract

A computational calculation to determine production capacity of 90Y from the results of nuclearreactions 89Rb(p,n)89Sr/90Y from several medical cyclotrons has been carried out. Calculations were used to obtain the target thickness of 89Rb and maximum activity of 90Y on variable energy, time and irradiation currents. Calculations were also carried out to measure the impurity radionuclide activity during the reaction. The results activities of 90Y were obtained through modeling using the SRIM-2013 software and the TENDL-2017 application and calculated using MATLAB software. The results modeling and of calculations can predict the activity of 90Y and it can be used as an initial reference in the radionuclide production process using a cyclotron. The maximum activity of 90Y of 5409.80 mCi with a 10.54 mm-target thickness of 89Rb is generated from a cyclotron which has a 30 MeV proton beam with a 50 μA radiation current beam and 2 hours irradiation time. Using the same proton, current and irradiation time at irradiation energy of 8 MeV, 15 MeV and 22 MeV, the produced activity of 90Y was smaller, there are 552.28 mCi, 2100.39 mCi and 3644.31 mCi. The radioisotope of 90Y can be used in patients with a normal dose of 0.4 mCi / kg body weight, therefore in one production can supply the needs of 104 patients.Keywords: medical cyclotron, calculation and modeling, 90Y activity
PENGUKURAN COMPUTED TOMOGRAPHY DOSE INDEX (CTDI) PADA FANTOM KEPALA DENGAN MENGGUNAKAN CT DOSE PROFILER Ahadiyah, Naeli Ni'matin; Setiawati, Evi; Arifin, Zaenal; Anam, Choirul
BERKALA FISIKA Vol 23, No 4 (2020): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

This study aims to  measure  computed  tomography  dose  index (CTDI) on  a  head  polymethyl methacrylate (PMMA) phantom using a CT dose profiler for various slice thicknesses. The slice thicknesses were 3, 5, and 10 mm. Dose measurements were performed in spiral mode for every hole  within  the  head  PMMA  phantom.  A  CT  dose  profile  analyzer  software  integrated  the profile  dose  along  100  cm  to  find  the  CTDI100.  The  CTDIw  was  calculated  as 1/3×(CTDI100,center)+2/3×(average CTDI100, perifer). Since the pitch was unity, the CTDIvol was similar to the CTDIw. The values of CTDIvol for slice thickness variations were from 45.7 mGy to 46.0 mGy.  This result indicated that there is no significant different of CTDIvol measured using CT dose profiler for slice thicknesses from 3 mm up to 10 mm.Keywords: CT dose profiler, CTDI, CTDI100, CTDIw, CTDIvol, slice thickness 
IMPLEMENTASI METODE CONTRAST LIMITED ADAPTIVE HISTOGRAM EQUALIZATION DAN LAPLACIAN OF GAUSSIAN FILTER UNTUK PENINGKATAN KONTRAS CITRA CT Awwalin, Aufi Rizqiatul; Setiawati, Evi; Anam, Choirul
BERKALA FISIKA Vol 24, No 1 (2021): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

The  image  obtained  from  the  CT  scanner  has  a  relatively  low  contrast.  Image  contrast  can  be enhanced  by  using  an  algorithm  of  contrast  limited  adaptive  histogram  equalization  (CLAHE). However, the implementation of CLAHE causes an increase  of noise. Furthermore, noise can be reduced  using  a  noise  reduction  filter,  but  it  reduces  the  spatial  resolution  of  the  image.  This study proposed a combination of the CLAHE method and the Laplacian of Gaussian (LoG) filter noise reduction algorithm to obtain images with high contrast,  while maintaining the  noise and spatial  resolution.  In  this  study,  27  abdominal  CT  images  and  MTF  phantom  CT  images  were investigated using our proposed method. As a comparison, this study also evaluated the results of combination  of  CLAHE  and  Gaussian  filters.  Evaluation  of  the  results  of  image  quality improvement  was carried out qualitatively (visually) and quantitatively by calculating the mean squared  error  (MSE),  peak-signal  to  noise  ratio  (PSNR)  and  spatial  resolution  using  a modulation transfer function (MTF) of 10%. The results of this study qualitatively (visually) and quantitatively showed that the combination of CLAHE and LoG filters produces images with high contrast,  while  maintaining the  noise  and  the  spatial  resolution  of  the  image.  Compared  to  the combination of  CLAHE and Gaussian filters or CLAHE alone,  the  combination of CLAHE and Log  filters  provides less  noise  and  higher  spatial  resolution.  Thus,  combination  of  CLAHE  and LoG filters can be used as an alternative algorithm to increase the contrast in CT images.
DETERMINATION OF THICKNESS AND OPTICAL BAND GAP OF POLYANILINE NANOFIBERS Ketut Umiati, Ngurah Ayu; Setiawati, Evi; Facta, Mochammad
BERKALA FISIKA Vol 24, No 3 (2021): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

The study observed the thickness and optical band gap of polyaniline nanofiber (PNF). PNF in this study is synthesized by the interfacial polymerization method in Toluene Aniline 0.31 with the APS 4mmol dopant HCl solution with molarity between 1 M to 3 M. The synthesis results obtained were characterized by UV-Vis scanning spectrophotometer. The thickness and absorption coefficient (α) is observed by Swanepoel method and Beer–lambert’s relation, respectively. The optical band gap is observed from extrapolation versus  . The results of this study indicate that the molarity of dopants affect the thickness layer and optical band gap of the material.
Analisis Produksi Plutonium-239 pada HTR-10 Menggunakan Program MCNPX Evi Setiawati; S Juliawan; Zaenul Muhlisin; F Arianto
Jurnal Ilmiah Aplikasi Isotop dan Radiasi Vol 16, No 2 (2020): Desember 2020
Publisher : BATAN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17146/jair.2020.16.2.5898

Abstract

Sebagai reaktor termal berdaya 10 MWt, HTR-10 dapat mengakomodasi berbagai macam campuran bahan fisile dan fertile. Kemampuan akomodasi tersebut sangat bermanfaat dalam menutup siklus bahan bakar nuklir dan menstabilkan keberadaan Plutonium-239 yang masih dapat digunakan dalam daur ulang bahan bakar. Plutonium-239 (Pu-239) merupakan salah satu nuklida hasil proses fisi yang dapat digunakan kembali sebagai bahan bakar reaktor. Pada HTR-10, densitas Pu-239 yang dihasilkan sangat dipengaruhi oleh ukuran kernel dan pengayaan bahan bakar yang digunakan. Analisis produksi Pu-239 pada penelitian ini dilakukan terhadap hasil pemodelan dengan menggunakan program MCNPX (Monte Carlo N-Particle Extended). Parameter model yang digunakan adalah variasi radius kernel 250-300 μm dan variasi pengayaan bahan bakar 12-15%. Simulasi MCPNX menghasilkan perubahan masa bahan bakar dan produksi unsur aktinida hasil reaksi fisi selama pengoperasian reaktor satu tahun. Berdasarkan perhitungan menggunakan program MCNPX, didapat hasil bahwa produksi Pu-239 paling optimal adalah pada pengayaan bahan bakar 11% pada radius kernel 300 μm. Dengan memperbesar pengayaan U-235 menyebabkan penurunan konsentrasi U-238. Karena Pu-239 dihasilkan dari U-238, maka produksi Pu-239 adalah Pu-239 yang mempunyai densitas rendah.
Modelling of HTR (High Temperature Reactor) Pebble-Bed 10 MW to Determine Criticality as A Variations of Enrichment and Radius of the Fuel (Kernel) With the Monte Carlo Code MCNP4C Hammam Oktajianto; Evi Setiawati; Very Richardina
International Journal of Science and Engineering Vol 8, No 1 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (34.27 KB) | DOI: 10.12777/ijse.8.1.42-46

Abstract

Gas-cooled nuclear reactor is a Generation IV reactor which has been receiving significant attention due to many desired characteristics such as inherent safety, modularity, relatively low cost, short construction period, and easy financing. High temperature reactor (HTR) pebble-bed as one of type of gas-cooled reactor concept is getting attention. In HTR pebble-bed design, radius and enrichment of the fuel kernel are the key parameter that can be chosen freely to determine the desired value of criticality. This paper models HTR pebble-bed 10 MW and determines an effective of enrichment and radius of the fuel (Kernel) to get criticality value of reactor. The TRISO particle coated fuel particle which was modelled explicitly and distributed in the fuelled region of the fuel pebbles using a Simple-Cubic (SC) lattice. The pebble-bed balls and moderator balls distributed in the core zone using a Body-Centred Cubic lattice with assumption of a fresh fuel by the fuel enrichment was 7-17% at 1% range and the size of the fuel radius was 175-300 µm at 25 µm ranges. The geometrical model of the full reactor is obtained by using lattice and universe facilities provided by MCNP4C. The details of model are discussed with necessary simplifications. Criticality calculations were conducted by Monte Carlo transport code MCNP4C and continuous energy nuclear data library ENDF/B-VI. From calculation results can be concluded that an effective of enrichment and radius of fuel (Kernel) to achieve a critical condition was the enrichment of 15-17% at a radius of 200 µm, the enrichment of 13-17% at a radius of 225 µm, the enrichments of 12-15% at radius of 250 µm, the enrichments of 11-14% at a radius of 275 µm and the enrichment of 10-13% at a radius of 300 µm, so that the effective of enrichments and radii of fuel (Kernel) can be considered in the HTR 10 MW. Keywords—MCNP4C, HTR, enrichment, radius, criticality 
Analysis Loading Height of HTR (High Temperature Reactor) Core to Obtain Criticlity of Reactor Evi Setiawati
International Journal of Science and Engineering Vol 9, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (274.058 KB) | DOI: 10.12777/ijse.9.2.

Abstract

High temperatur reactor (HTR) attract to be studied due to it has inherent safety characteristics and capabilities to produce energy economically. Design of reactor core in this study is a blend HTR 10 in China with HTR pebble-bed. The reactor has thermal power of 10 MW with inlet and outlet helium temperatures of 250oC and 700oC. HTR design is a cylindrical with helium gas as a coolant and graphite as a moderator. The HTR uses pebble-bed fuel composed a large amount of particles of TRISO in graphite metrics. Kernel radius used to analyse reactor core height in this research is 225 µm with enrichment of 16% in order to achieve critical condition. Reactor criticality is also influenced by the height of active reactor core where pebble-bed fuel is distributed. Calculation of the reactor criticality at any height variations active core is done with MCNP5 modelling techniques. The modelling is done by making the geometry of reactor and pebble-bed which is distributed by using body-centred cubic lattice in the reactor core. From the MCNP5 calculation, the first criticality of HTR can be achieved on the active core height of 150.9012 cm calculated from the bottom active core with criticality value of 1.00312±0.00090. The higher active reactor core is, the more increasing the reactor criticality is. This is occured due to there are many fuel balls of pebble-bed used, so that activity of fission in reactor increases. However, reactor criticality is still in stable condition in each the rise of active core height from critical core height even though reactor reactivity increases 0.01 Δk/k. The minimum of fuel needed to achieve initial criticality (critical core height) is 11,805 pebbles and 8,906 moderators.
PERHITUNGAN NILAI DOSIS DAN KONTRAS CITRA COMPUTED RADIOGRAPHY (CR) DENGAN VARIASI KETEBALAN DAN KOMBINASI JENIS FILTER Dessy Dian Monita Pardede; Evi Setiawati
Youngster Physics Journal Vol 3, No 4 (2014): Youngster Physics Journal Oktober 2014
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

The research about calculation of dose values and image contrast computed radiography has done with thickness variation and combination type filter.  Additional filters are ideal able to absorb all of the energy is low and continuing high energy X-rays. Materials filters are often used in radiodiagnostic is Aluminum (Al). This researc used material such aluminum (Al), stainless steel (Ss), Zinc (Zn) and combine the filter to get low dose withhigh contrast quality.The thickness of the filter are 0.5 mm, 1 mm, 1.5 mm, 2 mm of the three types of filter material with maximum combination thickness of the filter material is 2 mm.  Irradiation performed with a Shimadzu brand X plane by a factor of 3.55 eksposi 50 kVp and mAs with an area of 15 x 15 cm field using the object stepwedge. Dose measurements performed with the detector R100B while the contrast of the image is determined by calculating the gray value of image by using the technique of ROI (Region of Interest) on any object thickness stepwedge.Measurement of dose and image contrast value obtained some filters that generate a low dose with high image contrast. The use of one type of filter that produces low-dose and high image contrast are on filters Al 0.5 mm, Al 1 mm, Al 1.5 mm, Al 2 mm, Zn 0.5 mm, Zn 1 mm, Ss 0.5 mm. While the use of a combination of the type of filter that produces a low-dose and high image contrast value are on 0.5 mm Al + Zn 0.5 mm, 1 mm Al + Zn 0.5 mm, 0.5 mm Al + 0.5 mm Ss, 1.5 mm Al + Zn 0.5 mm, 1.5 mm Al + 0.5 mm Ss and  Ss 0.5 mm + 0.5 mm Zn. By combining this type of filter then obtained a lower dose compared with only one type of filter material. Keywords: Radiodiagnostic, additional filters, Dose, Gray value, Image contrast radiography, Computed Radiography (CR)
PERBANDINGAN EFISIENSI DETEKTOR SINTILASI ORGANIK MENGGUNAKAN SINTILATOR ANTRASEN DAN NAFTALEN SERTA PENGARUH PENGGUNAAN KONTAK OPTIK TERHADAP EFISIENSI DETEKTOR PADA SPEKTROMETER BETA Nur Indah Lestari; Evi Setiawati; Very Richardina
Youngster Physics Journal Vol 4, No 1 (2015): Youngster Physics Journal Januari 2015
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

Research has been done to improve the efficiency of the manufacturing scintillator detector  in beta spectrometer. Detector efficiency is influenced by the type of scintillator, so that in this research will compare the efficiency of the detector using different types of organic scintillator. Scintillator used in this study are Anthracene and Naphthalene. In addition to comparing the efficiency of the scintillator, in this research will analyze the influence of the optical contact of silicone oil to the detector efficiency.Research done by pressing stainless steel mold containing the powder scintillator Anthracene and  Naphthalene. Pressure exerted is 86.6 kN / m2. Naphthalene and Anthracene scintillator made some thickness variations, start from 1 mm to 5 mm with a range of 0.5 mm. Then do the enumeration given 137Cs radiation  source on the surface of  the scintillator PMT (Photomultiplier Tube). To determine the effect of optical contact, given a silicone oil  layer between the surface of  the scintillator with PMT.The results of  the research showed that the efficiency of  the detector with Scintillator Anthracene larger than the scintillator Naphthalene. Scintillator detector efficiency with  Anthracene has a value of 99%, while the efficiency of the scintillator Naphthalene is 53.42%. Silicone oil as an optical contact effect on anthracene with thickness of 1 mm, while on the other the thickness of silicone oil had no effect. In Naphthalene, silicone oil effect on all thickness. It was seen from the increase of efficiency.Keyword : beta spectrometer, Detector efficiency, organic scintillator, optical contact of silicone oil
Co-Authors Agus Margiantoro Ahadiyah, Naeli Ni'matin Ana Aprilia Anak Agung Gede Sugianthara Ardiansyah, Mustofa Ariyanti Nur Anisa Asep Yoyo Wardaya Awwalin, Aufi Rizqiatul Binu Soesanto, Qidir Maulana Bunawas Bunawas Choirul Anam Choirul Anam AM Diponegoro Cicilia Artitin Cory Amelia Dessy Dian Monita Pardede Djoko Heru Pamungkas Dodi Junaedi Dortua Helena Sidabutar Eko Hidayanto Elvira Situmorang Erna Mariani Evi Handriani Bertua Simamora F Arianto Fajar Arianto Galih Puspa Saraswati Gede Sutresna Wijaya Gutji, Nelyahardi Hammam Oktajianto Hammam Oktajianto Handini Devi Yunitasari Harahap, Nur Hasanah Ifa Istighfaroh Indras Marhaendrajaya Intan Andriani Jatmiko Endro Suseno K Sofjan Firdausi K. Sofjan Firdausi Kusworo Adi Maria Theresia Darini Masdi Masdi Maulana, Alsa Putra Mochammad Facta Mohammad Afif Rachmatulloh Much. Azam Muchammad Azam, Muchammad Mursiyatun Mursiyatun Nanang Suriansyah Ngurah Ayu Ketut Umiati Nina GInanto Putri Nur Indah Lestari Nurul Laili Khoirut Tabi’atin Pandji Triadyaksa Poppy Intan Thahaja Rahmadi Setyawan Rahmaningtyas, Avivah Riana Anis Safitri Ridwan Eko Susanto Rinarto Subroto S Juliawan S. Suryono Sanggam Ramantisa Sanggam Ramantisan Sanggam Ramantisan Sari, Devi Artika Setiyono Setiyono Stefani, Eska Sudrajat, Ignasius Suprih Sumariyah M.Si Sumariyah Sumariyah Suroto Suroto Susilo Hadi, Susilo Suwardi Suwardi Syahria Syahria Trisna Budiwati Verry Richardina, Verry Very Richardina Very Richardina Wijianto Wijianto Windarta, Jaka Yunianta Yusup Hidayat Zaenal Arifin Zaenul Muhlisin Zainul Muhlisin