Consider a particle moving on the surface of the unit sphere in R and heading towards a specific destination with a constant average speed, but subject to random deviations. The motion is modeled as a diffusion with drift restricted to the surface of the sphere. Expressions are set down for various characteristics of the process including expected travel time to a cap, the limiting distribution...

Wavelet transformation was applied as a noise elimination method of an amperometric algal biosensor. The drift of the baseline current was clearly removed by using the wavelet transformation. The S/N ratio, calculated by the power spectrum density, is about 3-times larger than that calculated by the current response. The response to a herbicide, atrazine, calculated from the power spectrum d...

By use of dynamic subtraction it is feasible to adopt phase-sensitive detection with a CCD camera to reduce long-term optical background drift. We report on a two-order improvement of the signal-to-noise ratio. The improved system is used to image terahertz field distribution generated by an optically rectified electro-optic crystal with a modulation depth as small as 10(-4). We also introduce ...

A permanent magnet stepper motor is modified to hold a dichroic polarizer inside the motor. Rotation of the polarizer by 90° ± 0.04° is accomplished within 80 ms. This device is used for measurements of the intensity ratio for two orthogonal linear polarized components of a light beam. The two selected polarizations can be rapidly alternated to allow for signal drift compensation, and the two s...

The fluid-kinetic hybrid electron model is verified in global gyrokinetic particle simulation of linear electromagnetic drift-Alfv enic instabilities in tokamak. In particular, we have recovered the b-stabilization of the ion temperature gradient mode, transition to collisionless trapped electron mode, and the onset of kinetic ballooning mode as be (ratio of electron kinetic pressure to magneti...

We report on the determination of the Yarkovsky effect among Near Earth Asteroids (NEAs). The related recoil force is modeled through an empirical transverse acceleration resulting in a secular semimajor axis drift. For a successful determination we use a precise dynamical model including perturber asteroids and planetary relativistic terms. We found a few tens of object with a significant dete...

An artificial neural network (ANN) modeling technique is introduced for sensor and associated instrument channel validation. This method utilizes a genetic algorithm search approach supplemented with standard linear correlations to empirically determine appropriate combinations of available input variables to perform each desired modeling. The Sequential Probability Ratio Test (SPRT), a statist...

The preamplifier is a critical component of gyrometer’s electronics. Indeed the resolution of the sensor is limited by its signal to noise ratio, and the gyrometer’s thermal stability is limited by its gain drift. In this paper, five different kinds of preamplifiers are presented and compared. Finally, the design of an integrated preamplifier is shown in order to increase the gain stability whi...

the aim of the present study was to investigate the influence of nozzle configurations on spray drift and explain the influences using several atomization characteristics (length of spray sheet, spray angle, velocity distribution of flow field, fluctuation of velocity, and droplet size). nozzles manufactured by one company (lechler gmbh, germany) were tested by spraying local tap water in a win...