Principle of the moving-mirror-pair interferometer and the tilt tolerance of the double moving mirror

A novel type of interferometer, the moving-mirror-pair interferometer, is presented, and its principle and properties are studied. The new interferometer is built with three flat mirrors, which include two flat moving mirrors fixed as a single moving part by a rigid structure and one flat fixed mirror. The optical path difference (OPD) is obtained by the straight reciprocating motion of the double moving mirror, and the OPD value is four times the physical shift value of the double moving mirror. The tilt tolerance of the double moving mirror of the novel interferometer is systematically analyzed by means of modulation depth and phase error. Where the square aperture is concerned, the formulas of the tilt tolerance were derived. Due to the novel interferometer's large OPD value and low cost, it is very applicable to the high-spectral-resolution Fourier-transform spectrometers for any wavenumber region from the far infrared to the ultraviolet. (C) 2008 Optical Society of America.

An augmented method for free boundary problems with moving contact lines

An augmented immersed interface method (IIM) is proposed for simulating one-phase moving contact line problems in which a liquid drop spreads or recoils on a solid substrate. While the present two-dimensional mathematical model is a free boundary problem, in our new numerical method, the fluid domain enclosed by the free boundary is embedded into a rectangular one so that the problem can be solved by a regular Cartesian grid method. We introduce an augmented variable along the free boundary so that the stress balancing boundary condition is satisfied. A hybrid time discretization is used in the projection method for better stability. The resultant Helmholtz/Poisson equations with interfaces then are solved by the IIM in an efficient way. Several numerical tests including an accuracy check, and the spreading and recoiling processes of a liquid drop are presented in detail. (C) 2010 Elsevier Ltd. All rights reserved.

Conformal irradiation to moving targets in heavy ion radiotherapy with raster-scanning beam delivery system: (II) feasibility experiments

Within the framework of the pilot heavy-ion therapy facility at GSI equipped with an active beam delivery system of advanced raster scanning technique, a feasibility study on actively conformal heavy-ion irradiation to moving tumors has been experimentally conducted. Laterally, real-time corrections to the beam scanning parameters by the raster scanner, leading to an active beam tracing, compensate for the lateral motion of a target volume. Longitudinally, a mechanically driven wedge energy degrader (called depth scanner) is applied to adjust the beam energy so as to locate the high-dose Bragg peak of heavy ion beam to the slice under treatment for the moving target volume. It has been experimentally shown that compensations for lateral target motion by the raster scanner and longitudinal target shift by the depth scanner are feasible.

adaptive location update mechanism for network-constrained moving objects in changeful traffic conditions

Natl Chiao Tung Univ, Dept Comp Sci