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All Journal International Journal of Electrical and Computer Engineering Reaktor BERKALA FISIKA SAINS DAN MATEMATIKA JURNAL SISTEM INFORMASI BISNIS Jurnal Sains Materi Indonesia YOUNGSTER PHYSICS JOURNAL Scientific Journal of Informatics Register: Jurnal Ilmiah Teknologi Sistem Informasi Journal of Physics and Its Applications
Vincensius Gunawan S.K.
Jurusan Fisika, Fakultas Sains Dan Matematika, Universitas Diponegoro, Semarang
Astronomy Chemical Engineering, Chemistry & Bioengineering Computer Science & IT Control & Systems Engineering Earth & Planetary Sciences Economics, Econometrics & Finance Electrical & Electronics Engineering Energy Materials Science & Nanotechnology Mathematics Physics

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Journal : SAINS DAN MATEMATIKA

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Prediction of 2D Isodose Curve on Arbitrary Field Size in Radiation Treatment Planning System (RTPS) Nugraheni, Dewi Tri; Gunawan, Vincensius; Anam, Choirul
JURNAL SAINS DAN MATEMATIKA Volume 23 Issue 1 Year 2015
Publisher : JURNAL SAINS DAN MATEMATIKA

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Abstract

The study on prediction of 2D isodose curves for atbitrary field size has been done. Isodose curve is very useful for plannning and evaluation of doses received by patients in the radiotherapy treatment. The percentage depth dose (PDD) and dose profiles data for standard field size (square) were obtained from measurements in the Kensaras hospital, Semarang Regency. Dose profiles were taken at a depth of 1.5 cm and a radiation source to skin distance (SSD) of 100 cm. The calculation of PDD data in any field size uses linear interpolation method. While the calculation of the dose profile curve uses the widening, narrowing and weighting interpolation method. Firstly, the calculation of PDD and dose profile for standard field sizes of 3x3, 10x10, 15x15 and 20x20 cm2 were carried out and the results were compared to the measurements. Secondly, the PDD and dose profile for arbitrary field sizes 7x7 dan 13x13 cm2 were calculated. After that, the isodose curves for arbitrary field sizes were generated. The results showed that PDD curves of standard field sizes have maximum deviation values < 5% compared to the measurements. While the dose profile curves for field sizes up from 5x5 cm2 have maximum deviation values approximately 5% which was less than measurement. The profile curve of field size of 3x3 cm2 has maximum deviation value >5%. These results showed that our proposed algorithm was relatively valid. In this study, the PDD, dose profile and isodose curves of arbitrary field sizes 7x7cm2 and 13x13 cm2 were succesfully generated.
The Effect of BaCO3 Compound Changes on the Formation of Magnetic Material BaFe12O19 Priyono, Priyono; Cahyono, Agung; Marhaendrajaya, Indras; Subagio, Agus; Gunawan, Vincensius
JURNAL SAINS DAN MATEMATIKA Volume 23 Issue 4 Year 2015
Publisher : JURNAL SAINS DAN MATEMATIKA

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BaFe12O19 is a permanent magnetic material which has superior properties to be excellent until the late of twentieth century. Some of the obstacles in the synthesis of the material using a stoichiometric composition is a difficulty to obtain a single phase and the second phase is always found. This research attempted to make modifications on the initial non-stoichiometric composition by varying the fraction of Ba/Fe through BaCO3 and Fe2O3 compound through solid state reaction mechanism. This solid state reaction was initiated by mixing various fractions of BaCO3 and Fe2O3 powder composition and compacted to produce a homogeneous mixture using a planetary milling. After drying and molding, it was obtained a homogeneous mixture like a cylinder with a diameter of 2:54 cm and a thickness of 0.5 cm. The BaFe12O19 phase was obtained by heating the sample at a temperature of 1200 ° C for 4 hours. To determine changes in the fraction of Ba/Fe before and after sintering, the samples were tested by X-Ray Fluorescence (XRF), while the structure and crystallinity were tested by X-ray diffraction (XRD) and Scanning Electron Microscope (SEM). The results showed that during the heating process, the reduction of barium fractions exceeded 5% from of their initial weight, while changes in the fraction of Fe was not significant. The results of structure and crystallinity measurement showed that the addition a substantial amount of barium carbonate can lead to the decrease of crystallinity from 35.271 nm to 11.265 nm.
Co-Authors Abd. Rasyid Syamsuri Adian Fatchur Rochim Agung Cahyono Agus Purwanto Agus Subagio Aris Kusnandar Asfan Muqtadir Choirul Anam AM Diponegoro Dewi Tri Nugraheni, Dewi Tri Farhatin Nurul Ihya Hendri Widiyandari Indras Marhaendrajaya Ircham Ali Kamsul Abraha Kusworo Adi Mahfudz Fauzan Ngurah Ayu Ketut Umiati Priyono Priyono Rachmad Gernowo Robert L Stamps Ryan Kurniawan Singgih Sugiarto, Singgih Suryono Suryono Susilo Adi Widyanto