A problem of estimating the movement and orientation of a mobile robot is examined in this paper. The strapdown inertial navigation systems are often engaged to solve this common obstacle. The most important and critically sensitive component of such positioning approximation system is a gyroscope. Thus, we analyze here the random error components of the gyroscope, such as bias instability and random rate walk, as well as those that cause the presence of white and exponentially correlated (Markov) noise and perform an optimization of these parameters. The MEMS gyroscopes of InvenSense MPU-6050 type for each axis of the gyroscope with a sampling frequency of 70 Hz are investigated, as a result, Allan variance graphs and the values of bias instability coefficient and angle random walk for each axis are determined. It was found that in the output signals of the gyroscopes there is no Markov noise and random rate walk, and the X and Z axes are noisier than the Y axis. In the process of inertial measurement unit (IMU) calibration, the correction coefficients are calculated, which allow partial compensating the influence of destabilizing factors and determining the perpendicularity inaccuracy for sensitivity axes, and the conversion coefficients for each axis, which transform the sensor source codes into the measure unit and bias for each axis. The output signals of the calibrated gyroscope are noisy and offset from zero to all axes, so processing accelerometer and gyroscope data by the alpha-beta filter or Kalman filter is required to reduce noise influence.

In this paper, a new method of usage forensics memory analysis for compromising the carrier-lock algorithm was proposed. The firmware of one popular 3G modem for security issues is investigated. A binary file is reverse engineered using IDA Pro Disassembler and the carrier-lock code algorithm is found. The reproduction of arithmetic and bitwise ARM commands under the IMEI to obtain the unlock code by way of just reverse engineering become impossible because of the algorithm complexity. Therefore the existed ARM code was used to generate the unlock codes on the fly via memory forensics technique and JTAG debugger. A new method was successfully tested on a set of different modem versions.

The nonlinear singularly perturbed convection-diffusion process of the adsorption mass transfer in multicomponent multilayer filter pollution, each layer of which consists of particles of microporous structure is modeled. We construct the asymptotic expansion resolving relevant model boundary problem and on this basis conduct numerical experiment that allows to evaluate the impact of the various components of the process for the distribution of contaminants in the filter.