Algorithm for motion detection and gait classification based on mobile phone accelerometer data

This paper briefly describes the development of information technology tools using biometric data, in particular, human gait parameters. The problems of assessing gait parameters using a mobile phone accelerometer in real conditions are briefly described. The relevance of this research is substantiated in the field of developing algorithms for assessing biometric gait indicators based on data from wearable devices. The main approaches to the processing of wearable device accelerometer data are considered, the main shortcomings and problems in improving the quality of gait parameter estimation are indicated. The algorithm for processing data from a mobile phone accelerometer is described. In the proposed algorithm, the selection of movement patterns during gait  in the recorded data is carried out on the basis of statistical information within the “floating” time window (frequency component with the maximum contribution to the spectrum of the accelerometer signal, the duration of the selected time segments), as well as on the basis of the value of the correlation coefficient, selected time segments. At the stage of data segmentation, the time window of searching of movement segments, as well as the allowable thresholds of selecting movements by their duration, change depending on the individual characteristics of the gait and human activity. The classification of the selected segments according to the nature of gait movements is carried out on the basis of a feed-forward neural network. The sigmoid was used as the activation function for the hidden layers, and the normalized exponential function was used for the output layer. The neural network was trained using the gradient backdescent method with cross entropy as an optimization criterion. Due to the selection of segments with a high correlation coefficient, the classification of data shows the quality of distinguishing movements above 95%

Optical AR coatings of the Mid-IR band for ZnGeP2 single crystals based on ZnS and oxide aluminum

In this work, the parameters of antireflection interference coatings based on alternating layers of ZnS/Al2O3 on the laser-induced damage threshold (LIDT) of ZGP crystals under the action of Ho:YAG laser radiation at a wavelength of 2.097 μm were determined. The coating deposition was carried out using the ion-beam sputtering method. The LIDT of the sample with a coating based on alternating layers ZnS and Al2O3 was equal to WEo = 3.45 J/cm2, and the LIDT of the uncoated sample was equal to WEo = 2.23 J/cm2. An increase in the optical breakdown threshold by ~55% was observed after the deposition of an AR coating based on ZnS and Al2O3 materials. An assumption was made about the absence of local fluctuations in the composition and mechanical stresses in the case of the coated sample, namely that this leads to good adhesion of the multilayer coating to the polished surface of the crystal, and as a result to an increase in the optical breakdown threshold as compared to the uncoated sample due to closure of the dangling chemical bonds and bulk defects emerging on the polished surface

Diffusion doping route to plasmonic Si/SiOx nanoparticles

International audienceSemiconductor nanoparticles (SNPs) are a valuable building block for functional materials. Capabilities for engineering of electronic structure of SNPs can be further improved with development of techniques of doping by diffusion, as post-synthetic introduction of impurities does not affect the nucleation and growth of SNPs. Diffusion of dopants from an external source also potentially allows for temporal control of radial distribution of impurities. In this paper we report on the doping of Si/SiOx SNPs by annealing particles in gaseous phosphorus. The technique can provide efficient incorporation of impurities, controllable with precursor vapor pressure. HRTEM and X-ray diffraction studies confirmed that obtained particles retain their nanocrystallinity. Elemental analysis revealed doping levels up to 10%. Electrical activity of the impurity was confirmed through thermopower measurements and observation of localized surface plasmon resonance in IR spectra. The plasmonic behavior of etched particles and EDX elemental mapping suggest uniform distribution of phosphorus in the crystalline silicon cores. Impurity activation efficiencies up to 34% were achieved, which indicate high electrical activity of thermodynamically soluble phosphorus in oxide-terminated nanosilicon

Findings to the flora of Russia and adjacent countries: New national and regional vascular plant records, 4

With this paper we continue a new annual series, the main purpose of which is to make significant floristic findings from Russia and neighboring countries more visible in Russia and abroad. In total, this paper presents new records for 48 vascular plant species from 6 Eurasian countries, obtained during field explorations, as well as during taxonomic revisions of herbarium materials. For the first time, a new locality of Leontopodium leiolepis is recorded for Russia, Rheum uzengukuushi for China, Rorippa prolifera for Lithuania, Lappula marginata for Kyrgyzstan and Tajikistan, Anthriscus caucalis, Chenopodium ficifolium, Euphorbia prostrata for Uzbekistan, Adonis × hybrida, Potamogeton × franconicus, Solidago × niederederi for the Asian part of Russia, Echinochloa esculenta, Poa jamalinensis, Puccinellia poecilantha for Siberia, Potentilla intermedia for the Caucasus, Rhynchospora alba for the Russian part of Altai, Poa sphondylodes, Veronica beccabunga for Eastern Siberia, Asclepias syriaca for the Republic of Altai, Chimaphila umbellata, Orobanche korshinskyi, Veronica scutellata for the Republic of Buryatia, Cirsium alatum, Thalictrum simplex for the Republic of Crimea, Thymus rariflorus, Th. terekensis for the Republic of Ingushetia, Berberis thunbergii, Crataegus maximowiczii, Prunus serotina for the Republic of Mordovia, Oenothera villosa for the Republic of Tatarstan, Astragalus sulcatus, Galium mollugo for the Republic of Tyva, Phragmites altissimus for the Chelyabinsk Region, Senecio dubitabilis for the Magadan Region, Asclepias syriaca, Galatella villosa, Potentilla recta for the Novosibirsk Region, Dodartia orientalis for the Omsk Region, Viola hultenii for the Sakhalin Region, Phragmites tzvelevii for the Samara Region and the Middle Volga, Jacobaea ferganensis for the Samara Region, Carex media, Impatiens parviflora for the Tyumen Region. There are some more findings which are not new for the region but they contribute significantly to the understanding of species distribution

Biological Earth observation with animal sensors

Space-based tracking technology using low-cost miniature tags is now delivering data on fine-scale animal movement at near-global scale. Linked with remotely sensed environmental data, this offers a biological lens on habitat integrity and connectivity for conservation and human health; a global network of animal sentinels of environmen-tal change

Directions for the Development of Domestic Self-propelled Artillery Systems Based on the Analysis of Samples of Artillery Weapons From the Leading Countries of the World

The armed aggression of the Russian Federation in the east of Ukraine has made significant adjustments to the domestic development of weapons and military equipment both in our country and abroad. The development of artillery weapons as the main type of effective engagement of the enemy according to the experience of the anti-terrorist operation (operation of the Joint Forces) is a priority, since a considerable percentage of the tasks of engaging the enemy with fire falls on artillery. This article discusses the formation of directions for the development of domestic self-propelled artillery systems based on the analysis of samples of artillery weapons from the militarily leading countries of the world. It should be noted that the widespread introduction of modern technologies and scientific and technical solutions to increase the effectiveness of the use of a model of weapons and military equipment is one of the main directions of the development of artillery weapons for a partial solution of problems associated with the development of forms of warfare

Effect of cabbage species on CO

The formation of the seasonal CO2 flux depending on the species of cabbage crops used for short-term summer green manuring of the fallow field in the Baikal forest-steppe zone was studied. In field experiments on gray forest soil during the warm season, CO2 emission rates per day were measured in options with white mustard (Sinapis alba L.) and oil radish (Raphanus sativus var. oleifera Metzg). The black follow served as the control. The total CO2 flux from the soil was calculated by identifying different periods in the fallow treatment technology (before sowing green manure crops, vegetation, and the period after biomass plowing). An increase in the intensity of CO2 release from the soil after the plowing of green mass was revealed. The enhancement of mineralization processes due to the newly received organic matter of mustard biomass was 27-100%, and radish - 48-142% in relation to the black fallow. The CO2 emission data corresponded with the yield and quality indicators of the studied cabbage crops. It has been established that from the position of regulation of carbon dioxide fluxes, the use of white mustard for short-term green manure in the conditions of the region is more expedient than oil radish

Calculation of the Incompressible Viscous Fluid Flow in Piston Seals of Piston Hybrid Power Machines

The article considers the calculation of the flow of a viscous incompressible fluid in piston seals of piston hybrid power machines. The most widely used and effective seals are considered: a smooth gap seal and a step-type gap seal, and—based on the references analyses—the initial boundary conditions for their calculation are determined. The laminar and turbulent flows in gap seals are calculated based on the well-known analytical relationships, experimental studies and flow models, including the k-ε, Menter’s Shear StressTransport (SST) and Reynolds Stress (RSM) turbulence models. The effectiveness of using each model to determine average velocities, flow rates, and velocity plots in the cross section of a gap seal, as well as the adequacy of the description of known physical laws, is estimated. The results proved that the RSM turbulence model is better for the gap seals of different types under different modes of motion