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"ABSTRAKTomoterapi memiliki pola iradiasi heliks yang akan membentuk junction dan membuat pola distribusi dosis terganggu. Variasi pola distribusi dosis yang disebabkan oleh pola iradiasi heliks disebut ripple atau thread effect. Nilai thread effect sangat dipengaruhi oleh nilai pitch dan nilai faktor modulasi. Nilai pitch optimal telah dipelajari oleh Kissick et al, yang sama dengan 0,86 / n di mana n adalah bilangan bulat. Selanjutnya, pengaruh faktor modulasi terhadap nilai thread effect telah dipelajari oleh Mingli Chen et al. Dalam penelitian ini, dua jenis target digunakan, target sederhana dan target kompleks, penambahan kasus yaitu adanya dose interrupt, dua jenis scanner yaitu EPSON 10000 XL dan VIDAR, serta dua jenis dosis, dosis tunggal dan Simultaneous Integrated Boost (SIB) dengan variasi pitch dan nilai faktor modulasi. Untuk nilai pitch, kami memvariasikannya dari 0,287; 0,35; hingga 0,43, sedangkan kami menggunakan variasi 2; 2,2; 2,5; 2,8; dan 2,9 untuk faktor modulasi. Hasilnya menunjukkan bahwa target kompleks memiliki nilai ripple sekitar 1%-2% lebih rendah daripada target sederhana. Selain itu, area dosis tinggi memiliki nilai ripple sekitar 0,5%-3% lebih rendah daripada area dosis rendah saat menggunakan SIB. Untuk gamma indeks didapat nilai >99% ketika menggunakan DQA Station dan >70% ketika menggunakan Film QA Pro untuk kriteria 3%/3mm. Dari hasil ini kami menemukan bahwa thread effect sangat dipengaruhi bentuk target, dan besarnya nilai dosis yang digunakan untuk kasus SIB. Selaint itu, posisi film sangat berpengaruh ketika menggunakan EPSON 10000XL dibanding ketika menggunakan VIDAR. Pada kasus interrupt dose, waktu terjadinya gangguan tidak terlalu mempengaruhi distribusi dosis.

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ABSTRACTTomotherapy has a helical irradiation pattern that will form a junction and made interfere dose distribution pattern. The variation of dose distribution pattern where it caused by the helical irradiation pattern is called ripple pattern or thread effect. Thread effect value is strongly influenced by the pitch and modulation factor value. The optimal pitch value has been studied by Kissick et al, which is equal to 0.86/n where n is integer. Furthermore, the effect of modulation factor against thread effect value has been studied by Mingli Chen et al. In this study, two types of targets were used, simple target and complex target, addition of cases namely dose interrupt, two types of scanners, EPSON 10000XL and VIDAR, and two types of doses, single dose and Simultaneous Integrated Boost (SIB) with varied pitch and modulation factor value. For the pitch value, we varied from 0.287, 0.35, to 0.43, whereas we used variation of 2, 2.2, 2.5, 2.8, and 2.9 for the modulation factor. The results show that complex target have ripple values around of 1%-2% lower than simple target. In addition, high doses area have ripple values around of 0.5%-3% lower than low doses area when using SIB. For gamma index, the value is >99% when using DQA Station and >70% when using Film QA Pro for criteria 3%/3mm. From this result we found that thread effect was influenced by target form and doses value used for SIB cases. After that, the position of film is very influential when using EPSON 10000 XL compared to when using VIDAR. In the case of an interrupt dose, the timing of the interference does not significantly affect the dose distribution."

"The comparison of automatic and manual methods analysis in determining Cs-137 isotope using gamma - spectrometer. The analysis of radioactive isotopes commanly used by Gamma Spectrometer...."

"identification of defective position control system for gantry gamma camera GCA-602A. An identification of defective position control gamma camera GCA-602A has been conducted. The aim of the identification is to allocate the cause of the defect of the gantry control position. Identification method utilized in this work is by testing hand-key switches, electric motor's contractor including the motor and all its wiring system of the control position...."

"ABSTRAKSweet sorghum is a kind of sorghum that contains high content of sugar in its stem. Sweet sorghum has a big potential to be developed in Indonesia owing to its wide adaptation and the fact that it can be used as raw material for liquid sugar, syrup, ethanol, and also as animal feed. Sweet sorghum has not been developed in Indonesia because of lack of a sweet sorghum variety. Improvement of available sweet sorghum genotype can be done among others through plant breeding program. First step on the plant breeding program is to increase the plant genetic variability. This might be done by introduction of varieties or by breeding to create new varieties. Induced mutation using Gamma irradiation can be used to increase the genetic variability of sweet sorghum. Mutation breeding using Gamma irradiation in sweet sorghum was aimed at improving the yield and quality of sweet sorghum.This research was conducted to study the effect of Gamma irradiation on sweet sorghum growth in the M1 generation, and to estimate the optimal dose range suitably for the breeding program. Beside, the objective of this research was to evaluate the genetic variability for the purpose of plant selection in the M2 generation.Plant materials consisted of 2 sweet sorghum lines introduced from ICRISAT namely line No. 79 and No. 83. Non-saccharin sorghum of local variety Fiigari was used as a control. The doses of Gamma irradiation treatment were 0, 100, 200, 300, 400, 500, 600, 700, 800, 900, and 1000 Gy. The Ml plants were sown in greenhouse at PATIR-BATAN Jakarta, and then were transplanted in the experimental field at Balitbiogen, Bogor. The M2 plants were grown in the experimental field at Lubang Buaya, Jakarta. Important agronomic traits such as plant height, spike length, stem diameter, and grain weight/spike were observed.The results indicated that sorghum lines gave different response to Gamma irradiation, and all measured variables were significantly affected. Irradiation gave morphology and physiology damages on sorghum like abnormality, sterility, and lethality in the Ml generation. The increase of irradiation doses increased physiological damage. Effective doses of Gamma irradiation for sweet sorghum was to be around 400-500 Gy, and the lethal doses 50% of sweet sorghum was around 800-1000 Gy. Putative mutation sometimes could be observed in the M2 generation. The treatment of Gamma increased genetic variability of plant height, spike length, stem diameter, and grain weight/spike. The highest genetic variability was found in the dose treatment of 200-300 Gy. Within this interval dose, there might be high probability to find desirable mutants for further breeding purpose. A number of 38 plants had been selected from the M2 population as putative mutants."

"Telah dibuat Automatisasi peralatan gamma scan berbasis computer. Peralatan ini dapat menggerakan detektor dan sumber radiasi secara manual atau automatis untuk keperluan pemeriksaan mal fungi pada kolom ataupun fasilitas lainnya dengan teknik gamma scan secara on-line. Automatic gamma scan yang telah dibuat menggunakan mikrokontroler sebagai pengendali utama dan ratemeter minekin seri 9302 sebagai pencacah radiasi. Peralatan ini dioperasikan dengan komputer sehingga data pengukuran dapat ditampilkan dalam bentuk grafik secara real-time dan data dapat dianalisis in-situ. Peralatan ini dapat digunakan untuk inspeksi kolom dengan jangkauan panjang tali sampai 100 m yang resolusi scan sebesar 2 s/d 167 step/m. Motor penggerak yang digunakan memiliki laju perpindahan sekitar 6 x 10-2 m/detik. Kesalahan mengidentifikasi posisi adalah 1,3 x 10-4%."

"Telah dilakukan pengukuran untuk menentukan OF berkas lapangan terbuka dan berkas filter wedge ternyata hasilnya tidak beda. Mengukur dosis primer tidak bisa dilakukan secara eksperimen melainkan secara teori, dengan cara ekstrapolasi kurva OF pada kedalaman 0,5 cm diperoleh sebesar 0,7066. Nilai PDD hasil pengukuran dari 0,5 cm sampai 20 cm tidak jauh berbeda dengan nilai yang berikan oleh BJR. Perbedaan keduanya berada dalam rentang -3,36% sampai 0,60%. Radiasi primer untuk kedalaman rendah ditentukan dengan pendekatan hubungan antara dosis relatif dengan luas lapangan sedangkan untuk kedalaman lebih tinggi dari 3 cm pendekatan dosis relative sebagai fungsi linier Z. Nilai PDD radiasi primer dibandingkan dengan nilai yang diberikan BJR dari 0,5 cm sampai 20 cm perbedaan dalam rentang -4,31% sampai 9,28%.

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A measurement has been performed to know the output factors for open and with wedge filters beams the result indicate the same value . Dose primary can?t measurement but just calculate and than primary OF from OF curve ekstrapolation for 0.5 cm deep are 0.7066. PDD value measurement for 0.5 cm to 20 cm there were not so difference value with PDD BJR. Both different are - 3.36% to 0.60%. Primary dose for less than 3 cm solution from dose relative linier with field size. If more than 3 cm solution from dose relative with Z. PDD primary dose compare with BJR for 0.5 cm to 20 cm are -4,31% to9,28%."

"Telah dilakukan pengukuran penumbra berkas radiasi pesawat Cobalt-60 tipe FCC 8000F dengan diameter sumber 2,3 cm menggunakan metoda radiografi dan ionometri untuk berbagai kondisi fantom/material penghambur dan juga variasi luas lapangan. Pengukuran gammagrafi pada dmaks dan lapangan 10,6 x10,6 cm menunjukkan lebar penumbra memiliki rentang 1,4 sampai 1,9 cm. Pengukuran dosis penumbra menggunakan bilik ionisasi berbentuk silinder pada kedalaman 10 cm dengan SSD 80 cm memberikan hasil bahwa dosis penumbra dipengaruhi oleh lapangan radiasi, dan homogenitas medium. Kehadiran aluminium (l=5cm) dengan diameter (1,5, 2,2 dan 2,5 cm) dalam medium air pada umumnya menurunkan dosis penumbra. Medium gabus dengan ketebalan semakin besar akan menghasilkan dosis penumbra semakin rendah sebaliknya untuk lapangan yang semakin besar, dosis penumbra yang dihasilkan semakin tinggi.

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Penumbra measurement has been done on Cobalt machine FCC 8000F with 2,3 cm diameter source using both gammagraphy and ionometry on several phantom condition, inserted absorber materials as well as different radiation fields. Gammagraphic measurement at dmax = 0.5 cm and 10.6 x 10.6 cm field showed penumbra in the range 0f 1.4-1.9 cm. Ionometric measurement at 10 cm depth showed strong effect of field size and inhomegeneity. Insertion of aluminum object (l=5 cm) with different diameter (1.5, 2.2 and 2.5 cm) caused decreasing penumbra dose. While on lung equivalent insertion material it tended to increase. Results in general showed the importance of extreme prudence in using such a large size Cobalt source for patient treatment."

"Telah dilakukan pene1itinuntuk mempelajari pengaruhradiasi gamma pada sifat kimidan fisika serbuk Neomycinsu1fat dan Streptomycin sulfat dengan 'dosis radiasi 0, 1020 dan 30 kGy dan penyimpanan2sampai 12 minggu.Perubahan sifat kimia yang terjadi diamati dengan kró-.matografi cairan-cairan tekann tinggi, sedangkan perubahansifat fisika diamati dengan spektroskopi resonansi spinelektron.Hasil pehguisn nenunjuk1an bahwa dosis radiasi danpenyimpanan memberikan pengaruh yang bermakna ( p(O,Ol )pada konsentrasiNeomycin sulfat. Pada Streptomycin sulfat,dosis radiasi memberikan pengaruh yang bermakna ( p .(O,01 ),sedangkan penyimpanan tidak memberikan pengaruh yang bermakna.Dosis radiasi 10, 20 dan: 30 kGy menimbulkari radikal bebasdengan konsentrasi masing.-masing 315,8 x 1o17 ; 375,3 X1017 dan 500,6 x 1017 spin/g üntuk Neomycin sulfat dan150 1 2X 1015 ; 182,5 x 1015 dan 205,5 x io spin/g untukstreptomycin sulfat. Penyirnpanan menyebabkan penurunan konsentrasiradikal bebas Neomycin sulfat den Streptomycinsulfat mengikuti persamaan eksponensial.......The effects of gamma radiation on'•che:•:? \f_ J) \•L•.' 'T /p1fsicalcharacteristic's of Neomycin sulphate and Streptomycin sulphatepowder with radiation doses of 0., 10 9 20 and 30 kGyand storage periods of 2 to 12 weeks were isvestigated.The chemical change was observed by high pressure liquidchromatography, while physical change by electron spinresonance spectroscopy.The results of the test showed that radiation dosesgave significant effect ( p( 0,01 ) on Neomycin sulphateconcentration. For Streptomycin sulphate, radiation dosesgave significant effect ( p4(0 9 01 ), but storage periodsgave no significant effect.Radiation doses of 10, 20 and 30 kGy produced free radicalsconcentration of 315 9 8 X 1017 ; 3753 X 10 17 and500 2 5 X 1017 spin/g for Neomycin sulphate respectively and150 9 2 X 10 ; 182,5 X 1015 and 205,5 X spin/g forStreptomycin sulphate. Storage periods caused the decreaseof Neomycin sulphate and Streptomycin sulphate free radicalsconcentration following exponential equation."

"[Distribusi Gamma-Half Normal merupakan distribusi kontinu yang dapat memodelkan data yang unimodal atau bimodal. Distribusi Gamma-Half Normal merupakan hasil pengkombinasian antara distribusi Gamma dan distribusi Half Normal dengan menggunakan metode Transformed-Transformer. Pembahasan meliputi pembentukan distribusi Gamma-Half Normal, fungsi kepadatan probabilitas, fungsi distribusi, fungsi hazard, dan karakteristik-karakteristik distribusi Gamma-Half Normal lainnya. Penaksiran parameter-parameter dari distribusi Gamma-Half Normal menggunakan metode maksimum likelihood. Dua kelompok data dibangkitkan untuk memberikan ilustrasi penggunaan distribusi Gamma-Half Normal., Gamma-Half Normal distribution is a continued distribution which can model unimodal or bimodal data. Gamma-Half Normal distribution is derived from Gamma distribution and Half Normal distribution using the Transformed-Transformer method. It will be explained how to form Gamma-Half Normal distribution, probability density function, cumulative distribution function, hazard function, and other characteristics of Gamma-Half Normal distribution. Maximum likelihood method is used for estimating Gamma-Half Normal’s parameters. Two sets data are used to illustrate the applicability of Gamma-Half Normal distribution.]"