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"Penempatan sumber radiasi pada radioterapi memerlukan ruangan khusus untuk menahan radiasi tidak menyebar keluar ruangan. Keselamatan pasien, staf dan masyarakat umum akan menjadi pertimbangan utama dalam pelaksanaan program pengobatan radiasi. Dinding perisai ruang radioterapi memiliki peranan penting dalam proteksi dan keselamatan radiasi. Ketebalan dinding perisai akan berbeda-beda sesuai energi radiasi dan beban kerja yang digunakan. Pembatas dosis di Indonesia sesuai dengan Perka Bapeten no.3 tahun 2013 yaitu nilai batas dosis untuk pekerja radiasi rata-rata 20 mSv per tahun selama 5 tahun dan untuk masyarakat 1 mSv per tahun. Penelitian ini menggunakan simulasi Monte Carlo MCNPX untuk membandingkan dosis yang dihasilkan agar tidak melebihi pembatas dosis yang ditetapkan. Pada Simulasi monte Carlo dibuat model ruangan, model Linac, energi radiasi sumber Linac, dan jenis material dinding yang digunakan sesuai dengan kondisi ruangan yang telah disetujui Bapeten. Pada penelitian dilakukan perhitungan dosis di luar dinding primer dan dosis pada kedalaman dinding penahan radiasi dengan material dinding benton berdensitas 2,35 g/cm3. Hasilnya tidak terbaca nilai dosis pada titik referensi dengan metode simulasi monte carlo pada penelitian ini. Sementara itu dosis pada dinding menunjukan penetrasi sampai dengan 160 cm pada dinding kiri, 200 cm pada dinding atas dan 180 cm pada dinding kanan.

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The placement of radiation sources in radiotherapy requires a special room to prevent radiation from spreading out of the room. The safety of patients, staff, and the general public will be a major consideration in the implementation of a radiation treatment program. The shield wall of the radiotherapy room has an important role in radiation protection and safety. The thickness of the shield wall will vary according to the radiation energy and the workload used. The dose limit in Indonesia is under Bapeten Perka No. 3 of 2013 which is the dose limit value for radiation workers an average of 20 mSv per year for 5 years and the community 1 mSv per year. This study uses a Monte Carlo MCNPX simulation to compare the resulting doses so as not to exceed the prescribed dose limit. In the Monte Carlo simulation, a room model, a Linac model, Linac source radiation energy, and the type of wall material used are made according to the room conditions that have been approved by Bapeten. In this study, the dose calculation outside the primary wall and the dose at the depth of the radiation retaining wall with a concrete wall material with a density of 2.35 g/cm3 were calculated. The result is not reading the dose value at the reference point with the Monte Carlo simulation method in this study. Meanwhile, the dose on the wall showed penetration up to 160 cm on the left wall, 200 cm on the upper wall, and 180 cm on the right wall."

"The monograph addresses a problem of stochastic analysis based on the uncertainty assessment by simulation and application of this method in ecology and steel industry under uncertainty. "

"This volume sharpens our picture of the applications of conformal invariance, introducing non-local observables such as loops and interfaces before explaining how they arise in specific physical contexts. It then shows how to use conformal invariance to determine their properties. Moving on to cover key conceptual developments in conformal invariance, the book devotes much of its space to stochastic Loewner evolution (SLE), detailing SLE’s conceptual foundations as well as extensive numerical tests. The chapters then elucidate SLE’s use in geometric phase transitions such as percolation or polymer systems, paying particular attention to surface effects. "

"The book presents homogeneous solutions in static and dynamical problems of anisotropic theory of elasticity, which are constructed for a hollow cylinder. It also offers an asymptotic process for finding frequencies of natural vibrations of a hollow cylinder, and establishes a qualitative study of several applied theories of the boundaries of applicability.Further the authors develop a general theory for a transversally isotropic spherical shell, which includes methods for constructing inhomogeneous and homogeneous solutions that allow the characteristic features of the stress-strain state of an anisotropic spherical shell to be revealed. Lastly, the book introduces an asymptotic method for integrating the equations of anisotropic theory of elasticity in variable thickness plates and shells."

"This volume contains surveys as well as research articles broadly centered on spectral analysis. Topics range from spectral continuity for magnetic and pseudodifferential operators to localization in random media, from the stability of matter to properties of Aharonov-Bohm and Quantum Hall Hamiltonians, from waveguides and resonances to supersymmetric models and dissipative fermion systems. This is the first of a series of volumes reporting every two years on recent progress in spectral theory."

"Telah dilakukan karakterisasi parameter kristal, sifat kemagnetan dan serapan gelombang mikro pada material berbasis lanthanum-strontium manganite komposisi La1-xSrxMnO3 (x=0-1) serta efek subsitusi parsial ion Fe dan Ti pada material komposisi La0.7Sr0.3Mn1-yFey/2Tiy/2O3 (y = 0-1). Preparasi material dilaksanakan melalui metode pemaduan mekanik diikuti dengan sintering pada temperatur 1100C selama 2 jam. Hasil pengujian dengan XRD terhadap material pasca perlakuan sintering memastikan material terdiri dari fasa kristalin. Diketahui bahwa ion Sr tidak dapat mensubsitusi ion La sepenuhnya pada senyawa komposisi La1-xSrxMnO3 dengan batas kelarutan x = 0.3 tanpa terjadi perubahan sistem kristal dan fasa tunggal. Substitusi ion Fe terhadap ion Mn pada senyawa komposisi La0.7Sr0.3Mn1-yFeyO3 (y=0-1) tidak menyebabkan perubahan struktur kristal yaiu tetap berstruktur monoklinik dikarenakan jari-jari ion Fe3+(6.4 nm) dan Mn4+ (5.4 nm) tidak jauh berbeda. Namun, tidak demikian dengan efek subsitusi parsial ion Ti4+ pada komposisi La0.7Sr0.3Mn1-yTiyO3 (y=0-0.8) ditandai dengan perubahan struktur kristal monoklinik pada y = 0 menjadi orthorombik pada komposisi 0 0.5 material memiliki fasa kedua yang mengindikasikan terdapatnya batas maksimum fraksi ion Ti4+ (jari-jari 6.05 nm) menggantikan ion Mn4+.

Efek subsitusi parsial ion Fe, Ti serta subsitusi bersama ion Fe dan Ti terhadap ion Mn menyebabkan perubahan struktur magnetik dari keteraturan ferromagnetik menjadi paramagnetik melalui suatu mekanisme interaksi pertukaran spin elektron. Perubahan sifat kemagnetan material ini diketahui dari loop hysteresis magnet melalui evaluasi menggunakan perangkat permeameter. Senyawa material berbasis lanthanum strontium manganite berbagai komposisi yang menjadi objek penelitian ini semua memiliki kemampuan menyerap gelombang elektromagnetik paling tidak pada jangkauan frekuensi 9–15 GHz yang diketahui berdasarkan analisis hasil pengujian dengan vector network analysis atau VNA. Hasil evaluasi menunjukkan material fasa tunggal komposisi La0.7Sr0.3Fe0.2Mn0.4Ti0.4O3 dengan ketebalan 2.05 mm dan bersifat paramagnetik memiliki nilai return loss maksimum sebesar -9.13 dB atau mampu menyerap gelombang mikro sebesar 65.05% pada frekuensi 10.9 GHz dan lebar frekuensi penyerapan optimum sebesar 4 GHz.

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Crystal parameter as well as magnetic properties and microwave absorption characteristics of material based on lanthanum-strontium manganese with La1- xSrxMnO3 (x = 0-1) compositions have been characterized. These are including the effects of partial substitution of Fe ions in La0.7Sr0.3Mn1-yFey/2Tiy/2O3 (y=0-1) series. Material preparation was carried out through mechanical alloying method followed by sintering at a temperature of 1100 0C for 2 hours. Identification study of x-rays traces for sintered materials ensured that all materials consisted of crystalline phases.

It is shown that Sr ion can completely substitutes La ion in the La1-xSrxMnO3 (x = 0.3) compositions with no change in the crystal system and remains as single phase materials. Similarly, there was also no crystal structure changing observed when Fe ion substituted the Mn ion in the La0.7Sr0.3Mn1-yFeyO3 (y=0-1) compositions. Apparently, the crystal structure was maintained due to almost similar size of ionic radii between Fe3+ (6.4 nm) and Mn4+ (5.4 nm). However, a different case occurred in Ti substituted La0.7Sr0.3Mn1-yTiyO3 (y=0-0.8) in which the crystal structure of monoclinic for y = 0 changed to orthorhombic for 0 0.5 which indicated that there must be a maximum ionic fraction limit of Ti4+ in replacing Mn4+ due to larger ionic radii (6.05 nm) than that of Mn4+.

It was also found that substitution of respectively Fe and Ti ions in La0.7Sr0.3Mn1- y(Fe,Ti)yO3 (y=0-1) series as well as co-substitution of Fe and Ti ions for Mn in La0.7Sr0.3Mn1yFey/2Tiy/2O3 series have lead to the magnetic structure changing from ferromagnetic order to paramagnetic through a mechanism of electron spin exchange interactions. The change in magnetic structure was seen from the hysteresis loop obtained by means of permeameter measurement. The lanthanum-strontium manganese-based materials of various compositions which were the objects of this study have shown the ability to absorb electromagnetic waves at least in the frequency range of 9-15 GHz. This was confirmed by results of analysis based on vector network analyzer (VNA). It is concluded that a paramagnetic single-phase material of La0.7Sr0.3Fe0.2Mn0.4Ti0.4O3 composition with 2.05 mm thickness has a maximum return loss value of 9.13 dB, which capable to absorb 65.05% of incident microwaves intensity at a frequency 10.9 GHz with the absorption width was 4 GHz."