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"ABSTRACTThe combination of the coupled mode and normal mode theories has been used to formulaic the theoretical performance represented by the coupling length and crosstalk parameters of the X-cut APE-LN SDC fabricated using the benzoic acid as the proton source, where in this case the matrix effective refractive index (MERI) method is applied for solving the symmetric and antisymmetric propagation constants of the normal modes propagating in this device. The corresponding near field method has been used to experimentally determine its crosstalk. The actual performance of this device is characterized by comparing the theoretically calculated with the experimentally determined crosstalk parameters. A software computer program has been developed in order to numerically characterize the entire characteristic and performance of the SDC under study. For the SDC under study, the best crosstalk obtained at the operating wavelength lamda =1.3 micrometer is ~0.21 dB for the interaction length L = 6 mm and the gap separation g = 5 mm. Its coupling length is ~ 1.33 mm. The propagation constant of the corresponding individual single-mode X-cut APE-LN channel waveguide making up this SDC is beta = 10.37901 micrometer, and thereby its effective refractive index is N cπ= 2.14743330. It has been shown that the fabricated SDC is very lossy. It has been deduced that its bad performance predominantly caused by the side diffusion effect, corresponding to the fabrication problem, where in this case the substrate sample has been not coated first with the buffer layer when the deposition of substrate sample with the aluminum mask was to be performed in the fabrication stages. Moreover, in this case only the simple annealing has been performed. The successive annealing process in order to reduce the coupling loss has been not applied yet. Under the assumption that the fabrication tolerances are such that the practical devices with coupling loss below 0.25 dB are feasible, the fabricated SDC under study is a 3 dB coupler. "

"Kita membandingkan dua bentuk propagator yang berbeda yaitu bentuk propagator yang disederhanakan dan bentuk propagator yang lengkap dari resonans nukleon spin-3/2 dan spin-5/2 dengan menggunakan model isobar dan pendekatan Lagranggian efektif pada fotoproduksi eta-meson pada proton γ + N -> η + N. Kita menghitung amplitude transisi dengan memasukkan suku Born, suku vektor-meson, dan resonans nukleon ( N1(1520)D13, N2(1535)S11, N3(1650)S11, N4(1675)D15, N5(1680)F15, N6(1700)D13, N7(1710)P11, dan N8(1720)P13 ). Parameter konstanta kopling diperoleh berdasarkan hasil perhitungan dari formula yang telah ditetapkan dengan data input berdasarkan data partikel.

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We compare two different propagator forms that are simple and complete propagators of spin-3/2 and spin-5/2 nucleon resonances by using isobar models and effective Lagrangian approach for eta-meson photoproduction on the proton γ + N -> η + N. We calculate the transition amplitudes by including Born term, vector-meson term, and nucleon resonances ( N1(1520)D13, N2(1535)S11, N3(1650)S11, N4(1675)D15, N5(1680)F15, N6(1700)D13, N7(1710)P11, and N8(1720)P13 ). The coupling constant parameters are obtained based on the calculation results based on the particle data group."

"Radioterapi adalah suatu modalitas penanganan kanker dengan memanfaatkan radiasi pengion. Teknik radiasi yang saat ini menjadi perhatian adalah radiasi partikel, salah satunya adalah proton. Proton memiliki karakteristik puncak bragg (Bragg peak) yang mendepositkan energinya pada jangkauan kedalaman tertentu. Salah satu teknik penyinaran radioterapi adalah Intensity Modulated Proton Therapy (IMPT). IMPT memiliki beam spot yang berukuran sangat kecil, sehingga memungkinkan distribusi dosis lebih konformal terhadap target. Organ paru-paru memiliki pergerakan yang membuat tantangan dalam pengerjaanya. Untuk mengurangi pengaruh pergerakan digunakan teknik 4D Computed Tomography (4DCT). Penelitian ini bertujuan untuk mengetahui tingkat efektivitas pengobatan kanker di paru-paru pada teknik radioterapi proton yang dibandingkan dengan radiasi foton sebagai acuan dasarnya. Selain itu, studi ini juga bertujuan untuk mengetahui besar perbedaan tingkat efektivitas perencanaan antara 3D CT dan 4D CT. Tingkat efektivitas perencanaan berdasarkan tiga parameter. Parameter tersebut yaitu Conformity Index (CI), Homogeneity Index (HI), dan Gradient Index (GI). Terdapat perbedaan yang cukup signifikan dari hasil perencanaan di kedua fantom tersebut. Untuk nilai CI dan HI nilai terbaik dapat dicapai pada fase ekspirasi. Namun untuk GI nilai terbaik dapat dicapai pada fase 0%. Dosis pada spinal cord setiap perencanaan, tidak memiliki perbedaan yang cukup signifikan. Kami menemukan pada paru-paru dengan teknik IMRT di fantom diam memiliki dosis melebihi ambang batas yang ditetapkan.

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The Intensity Modulated Proton Therapy (IMPT) technique is the most advanced technique in proton beam therapy. This is because IMPT can produce a dose distribution that is more appropriate to the target with a minimum dose in healthy organs. The use of radiotherapy for lung cancer cases has considerable challenges. This is due to the uncertainty of the range and movement of organs, which allows errors in planning to occur. 4 Dimension Computed Tomography (4DCT) is a technique that can provide temporal information on changes in healthy tissues and organs. Each phase generated from 4DCT, can provide information about the location, density, and volume of the target tissue and surrounding healthy organs. The use of all 4DCT planning phases in clinical practice has a very large workload, so one solution is to use only two extreme phases. This research was conducted by comparing the 10 planning phases using the IMPT technique. It aims to find out at what phase the best level of effectiveness is produced, based on the research data obtained. Evaluation was carried out based on the parameters of Conformity Index (CI), Gradient Index (GI), and Conformity Index (CI). The results of this study indicate that in the three parameters the best values ​​are in the two extreme phases. In the SFO and MFO techniques, the best CI value is in the 0% phase, while the HI value in the SFO technique is in the 50% phase and the MFO is in the 90% phase. In addition, for the GI value in both techniques, it is best to be in the 0% phase. "

"ABSTRAKDivais directional coupler dan optical switch merupakan komponen yangdibutuhkan dalam pemrosesan sinyal optik. Kemajuan teknologi wavelength divisionmultiplexing (WDM) dan pertumbuhan lalu lintas internet yang cepat memicu banyakpenelitian tentang teknologi switching optik. Galium Nitrida (GaN) merupakan materialsemikonduktor nitrida kelompok III yang menjadi kandidat menjanjikan untuk divaisyang beroperasi pada panjang gelombang komunikasi optik.Pada penelitian ini dilakukan desain directional coupler dan optical switchmenggunakan material GaN untuk panjang gelombang telekomunikasi, yaitu 1,55 um.Desain directional coupler terdiri dari pandu gelombang S-bend dan linear sedangkandesain optical switch berbasis Mach-Zehnder Interferometer yang terdiri dari duadirectional coupler yang dihubungkan dengan dua lengan persegi panjang. Optimasidesain dilakukan dengan metode finite difference beam propagation method (FD-BPM)menggunakan perangkat lunak OptiBPM. Optimasi dilakukan dengan memvariasikanparameter pandu gelombang meliputi lebar, ketebalan, width gap dan coupling gap.Dari hasil simulasi ditunjukkan bahwa lebar dan tebal terbaik untuk memperolehpropagasi single mode masing-masing adalah 4 um. Selanjutnya, berdasarkan hasiloptimasi ukuran pandu gelombang dilakukan desain directional coupler dan opticalswitch. Ditunjukan bahwa directional coupler dengan panjang 980 um dan lebar 15 umdengan width gap 7 um dan coupling gap 6 μm menghasilkan daya keluaran sebesar91,71% dengan splitting ratio sebesar 48,83% : 48,03%, excess loss dan power imbalanceberturut-turut sebesar 0,37 dB dan 0,07 dB.Tahap selanjutnya, berdasarkan lebar dan tebal pandu gelombang, dilakukanoptimasi desain optical switch. Dari hasil eksperimen numerik ditunjukkan bahwa desainoptical switch terbaik, memiliki panjang 6380 μm dan lebar 15 um, dengan panjangelektroda sebesar 4500 μm. Optical switch mampu beroperasi sebagai switch pada
 =34 V dengan insertion loss dan extinction ratio berturut-turut sebesar 1,23 dB dan 8,46 dB

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ABSTRACTDirectional coupler and optical switches are the components needed in opticalsignal processing. The progress of wavelength division multiplexing (WDM) technologyand the rapid growth of internet traffic have triggered much research regarding opticalswitching technology. Gallium Nitride (GaN) is a III-nitride semiconductor becomes apromising candidate for devices which operate in wavelength optical communications.In this research, the design of GaN-based directional coupler and optical switchdesign was conducted for telecommunication wavelength at 1.55 um. The design ofdirectional coupler consists of S-bend and linear waveguide, whereas, design of opticalswitch based on Mach-Zehnder Interferometer consists of two directional couplersconnected by two rectangular arms. Design optimization was conducted by finitedifference beam propagation method (FD-BPM) using OptiBPM software. Optimizationwas conducted by a varying waveguide parameter such as waveguide width, waveguidethickness, width gap and coupling gap.From the simulation results, the best of width and thickness were 4 um and 4 um,respectively, for support single-mode propagation. Next, based on the optimization resultof the waveguide dimension, it was conducted a design of the directional coupler andoptical switch. It was noticed that the directional coupler was 980 m long, and 15 umwide with width gap and coupling gap were 7 um and 6 μm, respectively. It generatedthe output power of 91.71% with the splitting ratio of 48.83 %: 48.03% while the excessloss of 0.37 dB and the power imbalances of 0.07 dB.The next step, optimization of the optical switch design was conducted based onthe width and thickness of the waveguide. From the simulation result, the best design ofthe optical switch was 6380 μm long and 15 um wide, with the electrode length was 4500μm. The optical switch could operate as an optical switch at = 34V with an insertionloss of 1.23 dB and an extinction ratio of 8.46 dB."

"Parallel-coupled wave-guide with symmetrical structure has interesting coupling characteristics and can be used as multiplexer/demultiplexer when certain working requirements are met. The coupling properties in the coupled wave-guide are analyzed theoretically on the basis of two mode interference effect of the propagating waves, wavelength dependence of wave-guide directional coupler is investigated in the coupling region. A rough approximation of the dependence is determined based on simplified transfer matrix multiplications followed by more detailed computer calculation using Beam Propagation method CBPMI.

By varying the dimensions of wave-guide such as width, thickness, gap, interaction length, refractive index difference and wavelength we could get different coupling properties, then the results of analysis are used to select the appropriate dimensions of multiplexer/demultiplexer that works on the range of wavelength (1.3 pm - 1.6 pm). This burned channel-type directional coupler is designed on Silicon substrate to be fabricated by sputtering technology."

"This book is intended as a text for undergraduate and graduate courses in aerodynamics, typically offered to students of aerospace and mechanical engineering programs. It covers all aspects of aerodynamics. The book begins with a description of the standard atmosphere and basic concepts, then moves on to cover the equations and mathematical models used to describe and characterize flow fields, as well as their thermodynamic aspects and applications. Specific emphasis is placed on the relation between concepts and their use in aircraft design. Additional topics of interest to the reader are presented in the Appendix, which draws on the teachings provided in the text. The book is written in an easy to understand manner, with pedagogical aids such as chapter overviews, summaries, and descriptive and objective questions to help students evaluate their progress. Atmospheric and gas tables are provided to facilitate problem solving. Lastly, a detailed bibliography is included at the end of each chapter to provide students with further resources. The book can also be used as a text for professional development courses in aerodynamics."

"The material contained in the book includes recent advances in experimental and theoretical fluid dynamics and will be of great use to those involved in either teaching and/or research."

"[ABSTRAKTumbukan ion berat menghasilkan suatu kondisi dimana jumlah proton dan neutronsama, hal ini disebut symmetric nuclear matter. Pemeriksaan terhadap karakteristikSNM masih dilakukan sampai saat ini. Efek suku non linear dianggapmemberikan kontribusi terhadap karakteristik dari SNM, selain itu pemeriksaanterhadap kestabilan persamaan keadaan dilakukan dengan menggunakan metodemedan rerata lanjutan. Pengecekkan lanjutan terhadap kestabilan persamaan energidilakukan dengan mengamati nilai kecepatan suara untuk setiap parameter. Solusidari persamaan densitas skalar, potensial skalar, dan turunan pertama potensialskalar ditunjukkan oleh titik potong ketiga kurva tersebut. Selain itu, pemeriksaanefek non linear terhadap kenaikan energi ikat dan tekanan setiap kenaikan temperaturjuga diperiksa. Parameter G2 yang memiliki konstanta suku cross couplingterbukti memberikan kontribusi menahan laju kenaikan energi pada SNM, hal inidiperlihatkan oleh kurva parameter G2 merupakan kurva paling soft. Kurva parameterNLZ merupakan kurva paling stiff, serta memiliki nilai Cs paling besar saat nilaimassa efektif tinggi. Kestabilan persamaan energi untuk setiap parameter masihdinilai realistik, ditinjau dari nilai C2s C2 < 1, namun setiap parameter memiliki daerahketidakstabilan saat massa efektif rendah karena nilai C2s negatif.

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ABSTRACTHeavy ion collision produces a condition where the total of proton equal with the total of the neutron this condition is named Symmetric Nuclear Matter SNM The investigation of SNM characteristic is still being done nowadays Effects of nonlinear term are considered to contribute to characteristics of SNM in addition to the examination of the stability equation of state were calculated using extended mean field method Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter The solution of scalar density equation scalar potential and first derivative of scalar potential are showed by crossing point of three curves The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature G2 which has cross coupling term contributes to restrain increasing of SNM energy it is shown by the G2 parameter curve is softest NLZ is stiffest and has biggest Cs value when high effective mass condition The stability of energy equation every Heavy ion collision produces a condition where the total of proton equal withthe total of the neutron, this condition is named Symmetric Nuclear Matter (SNM).The investigation of SNM characteristic is still being done nowadays. Effects ofnonlinear term are considered to contribute to characteristics of SNM, in additionto the examination of the stability equation of state were calculated using extendedmean field method. Advanced checking the stability of the energy equation is doneby observing the sound velocity values each parameter. The solution of scalar densityequation, scalar potential, and first derivative of scalar potential are showed bycrossing point of three curves. The investigation of non linear effects to the bindingenergy increasing and pressure every rise of temperature. G2 which has crosscoupling term contributes to restrain increasing of SNM energy, it is shown by theG2 parameter curve is softest. NLZ is stiffest, and has biggest Cs value when higheffective mass condition. The stability of energy equation every parameter couldbe said mentioned realistic, it is considered from C2sC2 < 1 value, but each parameterhas instability region when low effective mass condition is happened, because thevalues C2s are negative., Heavy ion collision produces a condition where the total of proton equal with the total of the neutron this condition is named Symmetric Nuclear Matter SNM The investigation of SNM characteristic is still being done nowadays Effects of nonlinear term are considered to contribute to characteristics of SNM in addition to the examination of the stability equation of state were calculated using extended mean field method Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter The solution of scalar density equation scalar potential and first derivative of scalar potential are showed by crossing point of three curves The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature G2 which has cross coupling term contributes to restrain increasing of SNM energy it is shown by the G2 parameter curve is softest NLZ is stiffest and has biggest Cs value when high effective mass condition The stability of energy equation every Heavy ion collision produces a condition where the total of proton equal withthe total of the neutron, this condition is named Symmetric Nuclear Matter (SNM).The investigation of SNM characteristic is still being done nowadays. Effects ofnonlinear term are considered to contribute to characteristics of SNM, in additionto the examination of the stability equation of state were calculated using extendedmean field method. Advanced checking the stability of the energy equation is doneby observing the sound velocity values each parameter. The solution of scalar densityequation, scalar potential, and first derivative of scalar potential are showed bycrossing point of three curves. The investigation of non linear effects to the bindingenergy increasing and pressure every rise of temperature. G2 which has crosscoupling term contributes to restrain increasing of SNM energy, it is shown by theG2 parameter curve is softest. NLZ is stiffest, and has biggest Cs value when higheffective mass condition. The stability of energy equation every parameter couldbe said mentioned realistic, it is considered from C2sC2 < 1 value, but each parameterhas instability region when low effective mass condition is happened, because thevalues C2s are negative.Key words: coupling, soft, stiff.ix]"