Rational solitons in deep nonlinear optical Bragg grating

We have examined the rational solitons in the Generalized Coupled Mode model for a deep nonlinear Bragg grating. These solitons are the degenerate forms of the ordinary solitons and appear at the transition lines in the parameter plane. A simple formulation is presented for the investigation of the bifurcations induced by detuning the carrier wave frequency. The analysis yields among others the appearance of in-gap dark and antidark rational solitons unknown in the nonlinear shallow grating. The exact expressions for the corresponding rational solitons are also derived in the process, which are characterized by rational algebraic functions. It is further demonstrated that certain effects in the soliton energy variations are to be expected when the frequency is varied across the values where the rational solitons appear

Dynamics of DNA Bubble in Viscous Medium

The damping effect to the DNA bubble is investigated within the Peyrard-Bishop model. In the continuum limit, the dynamics of the bubble of DNA is described by the damped nonlinear Schrodinger equation and studied by means of variational method. It is shown that the propagation of solitary wave pattern is not vanishing in a non-viscous system. Inversely, the solitary wave vanishes soon as the viscous force is introduced.Comment: 4 pages. arXiv admin note: substantial text overlap with arXiv:1112.471

Effects of lattice variations on confinement in photonic crystal microcavity using green tensor method

Electric field distribution in and around the 2D PC cavity was calculated for different lattice parameters using the Dyson formulation of the Green tensor. The results demonstrate the sensitive effects of structural variation of the photonic crystal on the effectiveness of field confinement in the cavity

Identifikasi Human Eror Pada Proses Produksi Cassava Chips Dengan Menggunakan Metode Sherpa Dan Heart Di PT. Indofood Fritolay Makmur

PT. Indofood Fritolay Makmur berusaha untuk menjaga keamanan, keselamatan dan Kenyamanan operator ditempat kerja yang memiliki potensi bahaya. Namun pada proses produksi cassava chips sering terjadi kecelakaan kerja yang disebabkan oleh human error seperti bekerja yang terburu-buru, sikap kerja yang salah, terjepit, dan tidak memnggunakan APD. Penelitian ini bertujuan untuk mengidentifikasi human error yang mengakibatkan terjadinya kecelakaan kerja pada operator proses produksi cassava chips dengan menggunakan Metode SHERPA dan HEART.Hasil dari penelitian ini, diketahui probabilitas human error yang dapat terjadi pada proses perendaman singkong yaitu sebesar 0,1288. Probabilitas human error yang dapat terjadi pada proses pemotongan singkong yaitu sebesar 0,1472. Probabilitas human error yang dapat terjadi pada proses penggorengan chips yaitu sebesar 0,6716. Probabilitas human error yang dapat terjadi pada proses pemberian bumbu pada chips yaitu sebesar 0,1008. Probabilitas human error yang dapat terjadi pada proses pengemasan yaitu sebesar 0,092. Nilai HEP tertinggi sebesar 0,6716 yaitu terdapat pada proses produksi penggorengan chips pada task memeriksa kematangan chips. Maka yang harus dilakukan untuk kelalaian operator dalam mengerjakan pekerjaannya dan dalam menggunakan APD yaitu dengan memberikan training secara berkala kepada semua operator, memberikan timer atau alarm pada saat proses penggorengan chips agar kematangan chips sesuai dengan standar mutu yang ada dan dilakukan pemeriksaan sebelum operator melakukan pekerjaannya

Study of Nonlinear Periodic Optical System

We give a brief review of some results of our study on one-dimensional shallow nonlinear Bragg grating with nonlinear modulation and deep nonlinear Bragg grating

Group-index and resonant field enhancement in a symmetric double-sided grated waveguide

A numerical study has been carried out by means of the Green’s function method to explore possible performance improvements of a simple grated waveguide (GWg) by the variations of its grated structure. It is shown that a GWg featuring symmetric two-sided grated structure of 16 teeth with a 60nm groove depth and having a symmetric refractive index profile with a relatively large contrast between the grated and ungrated layers is capable of delivering largely improved device performance compared to that achieved previously with a one-sided grating of 40nm groove depth and asymmetric index profile

Performance changes of a grated waveguide at resonance wavelengths next to its band-edges due to modified edge sections

An efficient numerical scheme developed on the basis of Green’s function method is applied to the investigation of structural effects on the performance of planar grated waveguide at the first resonance wavelengths next to the band-edges. Restricting ourselves to the transverse-electric waves, this study is focused on the effects induced by variations of the grating cell number and the depths of its four outer grooves on both sides. The different patterns of groove depth gradation or apodization considered in this study are all characterized by decreasing depth toward the ends while retaining the longitudinal grating symmetry. The effects of the modifications are expressed in terms of changes in the modal transmittance, reflectance, and out-of-plane scattering loss as well as the group velocity and resonant field enhancement. The most favorable result characterized by 15% transmittance enhancement and 85% loss reduction is achieved for the case with the most gradual changes in the groove depth. It is further shown that, for the investigated range of parameters, both the group velocity and field enhancement can best be improved by increasing the length of the uniform grating, without introducing any modification