Technological Features of the Liquid-Solid State of the Boundary Layer in the Processes of Bimetallic Products

The hydrodynamic and thermal state in the contact zone of the layers of a bimetallic product obtained by pouring liquid iron onto a solid steel billet, which changes in time and is responsible for the strength of the diffusion joint and the geometric parameters of the transition layer, has been investigated. Simplified analytical dependences, mathematical modeling data and experimental results of the liquid phase existence time in the contact zone based on research of the melt velocities during pouring and changes in the thermal field are presented. It is shown that simplified calculations data coincide in order and are close in values ​​to the calculations of mathematical modeling and experimental data, which makes it possible to use them for preliminary rough estimates by technologists and metallurgists.

Research on the Use of Neural Network for the Prediction of College Students’ Mental Health

A healthy mental status of students plays an important role in getting quality of education. Hence, research on the prediction of college students’ mental health status is of great importance and considered as a hot area of research. In this specific research study, back propagation (BP) algorithm is adopted to learn verities of characteristics of different students from the historical data of the students including: psychological characteristics, basic personal characteristics, and socio-economic characteristics. In the initial stage of the modeling, data preprocessing steps are used to prepare the data to be used by the BP algorithm for building model. The rationales behind the use of BP algorithm are its capability of handling heterogeneity of data and exploring correlations among different characteristics. The proposed model enhances the capability of BP algorithm for risk prediction of psychological problem of the students and achieves higher precision of psychological problem prediction. The results obtained show that the error between the predicted and measured values is 0.88%.

Assessment of the resource potential of agricultural organizations in the Kurgan region

The purpose of the research is to comprehensively assess the resource potential of agricultural organizations in the Kurgan region to form the trajectory of their development and determine the contribution to agricultural production in the region. Methods. The study was based on the use of statistical and econometric methods for collecting, processing, modeling data. It is based on the assessment of the use of the following functional components of the resource potential: land, material and technical, personnel, innovation and financial. At the same time, the dynamic assessment for each subspecies of the resource potential gives an idea of the trend in the volume and level of resource use, and the stochastic assessment – to identify the relationship between the indicators of resource investment and their return. Results. The presented assessment of the existing relationships between the quantitative and qualitative indicators of the resource potential and its subspecies indicate, on the one hand, an acute shortage of certain types of resources, and, on the other hand, an increasing intensity of their use without a proportional level of return. The study allows us to conclude that it is necessary to develop levers for managing the resource potential of agricultural organizations based on the symbiosis of the needs of agricultural producers and the territory in which they operate. Scientific novelty. The research methodology allows combining several methods of assessing (dynamic and stochastic) in achieving the final result, as well as assessing the elasticity between the general level of resource productivity of agricultural organizations and indicators of the efficiency of using the main types of resources. This approach makes it possible to form a sequence of actions to ensure an increase in the level of development and use of the resource potential of agricultural organizations.

Applications in remote sensing and environmental analysis

The present study aims to describe the morphologic and geographic structuring and report a relief morphometric analysis in a cutout of the environmental planning. To do so, geoprocessing techniques were widely used and supported by systemic theory. The main objective is to process relief data in Geographic Information System (GIS) and contribute to the database of characteristics from different local geomorphometric variables. Thus, the theorical basis of the research suggests the use of General System Theory based on their concepts to understand the morphologic structure of the relief at different levels, also the condition of the relief shapes and their classification. This case study occurs methodologically, defining the relief category as an environmental component of direct and vital interaction with other resources and dynamic components, considering mainly the whole environmental system. In this study, the environmental system is the Sucuriú River watershed. Therefore, to get the environmental analysis of the relief, the methodology consists of pre-processing and processing of digital land modeling data based on Synthetic Aperture Radar (SAR) records. Those can obtain different characteristics by using the methodology of geomorphometric variables extraction, which are the set of variables subject to land measuring. The results should cartographically reveal the dynamics and structural morphology of the relief, observing important parameters of relief configuration and concluding with the presentation and correlation of the relief shapes dynamics in all the considered environmental system.

Concentration-Dependent Association of Flavylium Chloride with Differential Hydroxy Moieties in Ethanol

Flavylium ions (6a–6e) were synthesized using Aldol condensation to compare the spectroscopic properties caused by the different numbers and locations of hydroxy groups on the flavylium cations (AH+). Without the addition of acid, increasing the concentration of flavylium ions to 10 mM in ethanol led to the following observation. The flavylium ions with the least number of OH groups (6a and 6b) showed a change in peak at higher concentrations, whereas 6c and 6d did not show the same degree of change in their 1H-NMR signals. This suggests an equilibrium that shifts the isomers B, CE, and Cz more towards the flavylium ion with more OH groups even at low concentrations. One possibility for the cause of this shift is that the flavylium ions become more stable through aggregation. In addition to the NMR results, the UV measurements confirmed that isomers with fewer OH groups showed a more dramatic shift towards the flavylium ion at higher concentrations. Using modeling data at DFT//B3LYP/6311**G(d) level, the self-association was investigated to show that the hydrogen bonding of OH groups is the main player but cannot stabilize entirely without the presence of the chloride ion in the complex.

Conceptualizing and Measuring Appetite Self-Regulation Phenotypes and Trajectories in Childhood: A Review of Person-Centered Strategies

This review uses person-centered research and data analysis strategies to discuss the conceptualization and measurement of appetite self-regulation (ASR) phenotypes and trajectories in childhood (from infancy to about ages 6 or 7 years). Research that is person-centered provides strategies that increase the possibilities for investigating ASR phenotypes. We first examine the utility of examining underlying phenotypes using latent profile/class analysis drawing on cross-sectional data. The use of trajectory analysis to investigate developmental change is then discussed, with attention to phenotypes using trajectories of individual behaviors as well as phenotypes based on multi-trajectory modeling. Data analysis strategies and measurement approaches from recent examples of these person-centered approaches to the conceptualization and investigation of appetite self-regulation and its development in childhood are examined. Where relevant, examples from older children as well as developmental, clinical and educational psychology are drawn on to discuss when and how person-centered approaches can be used. We argue that there is scope to incorporate recent advances in biological and psychoneurological knowledge about appetite self-regulation as well as fundamental processes in the development of general self-regulation to enhance the examination of phenotypes and their trajectories across childhood (and beyond). The discussion and conclusion suggest directions for future research and highlight the potential of person-centered approaches to progress knowledge about the development of appetite self-regulation in childhood.

Optical Configuration Effect on the Structure and Reactivity of Diastereomers Revealed by Spin Effects and Molecular Dynamics Calculations

The peculiarities of spin effects in photoinduced electron transfer (ET) in diastereomers of donor-acceptor dyads are considered in order to study the influence of chirality on reactivity. Thus, the spin selectivity—the difference between the enhancement coefficients of chemically induced dynamic nuclear polarization (CIDNP)—of the dyad’s diastereomers reflects the difference in the spin density distribution in its paramagnetic precursors that appears upon UV irradiation. In addition, the CIDNP coefficient itself has demonstrated a high sensitivity to the change of chiral centers: when one center is changed, the hyperpolarization of all polarized nuclei of the molecule is affected. The article analyzes the experimental values of spin selectivity based on CIDNP calculations and molecular dynamic modeling data in order to reveal the effect of optical configuration on the structure and reactivity of diastereomers. In this way, we succeeded in tracing the differences in dyads with L- and D-tryptophan as an electron donor. Since the replacement of L-amino acid with D-analog in specific proteins is believed to be the cause of Alzheimer’s and Parkinson’s diseases, spin effects and molecular dynamic simulation in model dyads can be a useful tool for investigating the nature of this phenomenon.

Accounting for spatial sampling patterns in Bayesian phylogeography

Statistical phylogeography provides useful tools to characterize and quantify the spread of organisms during the course of evolution. Analyzing georeferenced genetic data often relies on the assumption that samples are preferentially collected in densely populated areas of the habitat. Deviation from this assumption negatively impacts the inference of the spatial and demographic dynamics. This issue is pervasive in phylogeography. It affects analyses that approximate the habitat as a set of discrete demes as well as those that treat it as a continuum. The present study introduces a Bayesian modeling approach that explicitly accommodates for spatial sampling strategies. An original inference technique, based on recent advances in statistical computing, is then described that is most suited to modeling data where sequences are preferentially collected at certain locations, independently of the outcome of the evolutionary process. The analysis of georeferenced genetic sequences from the West Nile virus in North America along with simulated data shows how assumptions about spatial sampling may impact our understanding of the forces shaping biodiversity across time and space.

Development of a method for designing specialized machinery based on a hinge tractor

The method of designing frames of special machines for road construction and public utilities is considered, which allows you to design special machines with a given level of reliability and durability. The technique allows using modern computer modeling systems to carry out constructive refinement of the base tractor frame using experimental and mathematical modeling data. Using the design feature of tractors of the T–150K family, namely the presence of an articulated joint, it is possible, using a modular principle, to quickly design various machines for various industries. However, in order to design reliable machines, one must have a methodology for designing such machines. There is currently no such technique. When designing special machines, designers perform calculations only for working equipment. But as practice shows, the critical elements of the machine in this case, the support of the vertical hinge of the tractor frame during the operation of the pressurized machine (wheeled bulldozer and front loader), experience shock loads that lead to the destruction of the frame of the base tractor. The purpose of the article is to develop a methodology for designing a complex of road–building machines on the basis of mass–produced tractors with an articulated frame produced by public limited company "KhTZ".