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The dynamics of magnetic islands including toroidal rotation in tokamaks is studied. It is found that the contribution of toroidal rotation to the dynamics of magnetic islands is mainly through the coupling of magnetic curvature with pressure and density. In the presence of toroidal rotation, pressure and density are poloidal asymmetric. Then, their coupling with magnetic curvature provides a perpendicular current, and a corresponding return parallel current is induced to affect the dynamics of magnetic islands. It is found that the effect of toroidal rotation depends on its magnitude, rather than the shear. It also depends on the relative magnitude of the island propagation frequency to sound frequency. When the Mach number is large enough, the effect of toroidal rotation is stabilizing and dramatic, and overcomes the contribution of polarization current, namely the onset threshold of NTMs increases. Further, it is also suggested that the toroidal rotation plays an important role in the stability of small scale magnetic islands.

Road sector development policy in Bangka Belitung emphasis on equitable development, which is opening up new areas for industrial development zones of potential marine and coastal tourism, so that having an impact on the budget priority to build a new road. This led to a minimal budget provided for the maintenance of the existing road. This study aimed to evaluate the condition of the pavement both functionally and structurally, the growth of traffic density and the availability of existing road maintenance costs. Then, to analyze the influence of existing road conditions, traffic density and road maintenance costs to the type of road maintenance management. The results are compared with the results of the existing maintenance conducted by the Public Works Department of Bangka Belitung province. Evaluation of pavement conditions consists of visual assessment of pavement condition using IRI, pavement condition assessment functionally with deflection method using test data tool Benkelman Beam (BB) and the actual traffic load. IRI value, deflections and traffic growth gained from years 2011-2015 subsequently created regression models to obtain the relationship and the correlation coefficient. The analysis showed that using the same relative magnitude of the budget from 2011 to 2015, giving priority to the maintenance of the road with good conditions capable of providing the road with a steady state of 100%. Recommendations can be given that maintain the road with good conditions reflecting that preservation provide maximum results with the more efficient maintenance cost.

The near-field and far-field second harmonic (SH) responses of a metal spherical nanoparticle placed in the focal region of a highly focused beam are investigated by using the calculation model based on three-dimensional finite-difference time-domain (FDTD) method. The results show that off-axis backward-propagating SH response can be reinforced by tightly focusing, due to the increase of the relative magnitude of the longitudinal field component and the phase shift along the propagation direction.

The dynamically screened three-Coulomb-wave (DS3C) method is applied to study the single ionization of potassium by electron impact. Triple differential cross-sections (TDCS) are calculated in doubly symmetric geometry at excess energies of 6, 10, 15, 20, 30, 40, 50 and 60 eV. Comparisons are made with recent experimental data and theoretical predictions from a three-Coulomb-wave (3C) and distorted-wave Born approximation (DWBA). The DS3C method is able to reproduce most of the trend of experimental data and in good agreement with DWBA results. It is shown that the DS3C calculation provides much better shape and relative magnitude agreement with experiment.

Photoionisation cross sections for the ground level and some excited ns levels (n up to 14) of neutral sodium have been computed for low photoelectron energies. Starting from a single-particle central-field model, perturbation theory is used to estimate the contribution of potential corrections and core-polarisation effects. For the ground level in the agreement between our results and previous data (experimental and theoretical) is greatly improved by the inclusion of these corrections. The evolution of cross sections and core-polarisation effects along the ns Rydberg series is investigated; core-polarisation effects have larger relative magnitude for the ground level and the low excited levels than for the high excited ones.

Observations of K-edges are made for solid targets compressed by laser-generated coalescing shocks. Using a short pulse blacklighter to avoid radiative pre-heating of the compressed solid, a blue-shifted chlorine K-edge is observed. Comparisons with simple theoretical models have indicated the relative magnitude of the competing contributions to the shift.

By measuring the 3s 1.3P1-2p6 1S0 emission of Ne, both direct excitation of the target and charge-exchange excitation of the projectile to the same level have been studied in the energy range from 150 keV to 1 MeV, corresponding to impact velocities between 0.5 and 1.5 au. Comparison of the measured cross sections with existing data for the excitation of resonance states in H++H and He++He collisions shows similarities in the relative magnitude of the direct and the charge-exchange processes which are discussed.

A Ginzburg-Landau model for the commensurate-incommensurate phase transition with coupling between solitons and elastic distortions in one dimension is treated. The model was recently studied by other authors but only incomplete solutions were given. Depending on the relative magnitude of coupling constants the authors find two regions of first- and second-order transitions, separated by a line of tricritical points. The previous results by Bruce, Cowley and Murray (1978) and by Bak and Timonen (1978) are found as limits for stiff and soft elastic distortions.

Numerical results are presented from the study of local environment effects on the magnetic properties of atoms in simple models corresponding to the three typical alloys rh-ni, rh-pd and cu-ni. It is shown that (i) the dependence of the susceptibilities upon concentration and environment, (ii) the importance of the selfconsistent calculation of the charge transfers and the energy levels, (iii) the connection between the relative position of the energy levels and the relative magnitude of the susceptibilities, and (iv) that the susceptibility of the central atom is mainly determined by the electron-electron interactions on the central atom for rh-ni and rh-pd but that in cu-ni atoms further than the first neighbours need to be considered.

The angular distribution of neutral H(D) atoms produced in H-(D-)-Ar detachment collisions has been measured in a crossed-beam arrangement for collision energies from 50 to 250 eV and for the angular range from 0 to 15 degrees . A pronounced structure is observed indicating two components in the angular distribution of the neutral atoms, one located around 0 degrees and the other at Elab theta lab=220+or-10 eV deg. The relative magnitude of the two components varies with the projectile velocity, the small-angle component becoming more important with increasing velocity. The observed structure is attributed to the competing influence of electrostatic and dynamical coupling in the detachment process.

The accuracy with which the initial externally maintained photoelectric current I0 can be measured in various electronegative gases is discussed and is shown to depend on the relative magnitude of the coefficients of ionization and attachment and of backscattering.