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Developing efficient path-planning algorithms is an essential topic in modern robotics and control theory. Autonomous rovers and wheeled and tracked robots require path generators that can efficiently cover the explorable space with minimal redundancy. In this paper, we present a new path-planning algorithm based on the chaotic behavior of the Courbage–Nekorkin neuron model with a coverage control parameter. Our study aims to reduce the number of iterations required to cover the chosen investigated area, which is a typical efficiency criterion for this class of algorithms. To achieve this goal, we implemented a pseudorandom bit generator (PRBG) based on a Courbage–Nekorkin chaotic map, which demonstrates chaotic behavior and successfully passes all statistical tests for randomness. The proposed PRBG generates a bit sequence that can be used to move the tracked robot in four or eight directions in an operation area of arbitrary size. Several statistical metrics were applied to evaluate the algorithm’s performance, including the percentage of coverage of the study area and the uniformity of coverage. The performance of several competing path-planning algorithms was analyzed using the chosen metrics when exploring two test areas of the sizes 50 × 50 cells and 100 × 100 cells, respectively, in four and eight directions. The experimental results indicate that the proposed algorithm is superior compared to known chaotic path-planning methods, providing more rapid and uniform coverage with the possibility of controlling the covered area using tunable parameters. In addition, this study revealed the high dependence of the coverage rate on the starting point. To investigate how the coverage rate depends on the choice of chaotic map, we implemented six different PRBGs using various chaotic maps. The obtained results can be efficiently used for solving path-planning tasks in both real-life and virtual (e.g., video games) applications.

This document describes how to construct a heroic transmission used in the mechanization of agricultural machinery. The article discusses the basic principles, design features and advantages of heroic transmission. Various methods of designing heroic programs are also considered. Based on the information considered, a method for designing a heroic transmission was developed. Based on the calculation, sketches of the impeller of the hero gear were developed. Based on the sketch of the outer wheel and the eccentricity, the obtained data were substituted into the parametric equation of the eccentroid cycloid, the profile of which is the basis for the construction of the inner wheel of the rocking pair. Based on the sketch, a 3D model of heroic transmission was developed, which was based on mathematical modeling.

This document describes the calculation procedure for selecting the optimal parameters of the boom lifting mechanism in agricultural machinery. A boom lifting scheme was developed. Studies have been carried out to find the optimal values of linear dimensions and angle, at which the required value of the force developed by the drive when lifting the boom with a hydraulic cylinder of the specified dimensions will be minimal. Based on the results of the study, an algorithm was developed for solving the optimization of boom lifting parameters. An expression is obtained for the objective function of optimizing the boom lifting mechanism. Algorithm for selection of optimal parameters of lifting mechanism considering weight of boom, hydraulic cylinder and rod has been developed.

This document describes the effect of undissolved gas on the bulk modulus of the fluid. The concept of liquid compressibility and dependence on composition, temperature and pressure is considered. Various methods of measuring the modulus of volumetric elasticity of the liquid were considered. It was also proposed to improve the mathematical model for calculating the module of volumetric elasticity of a liquid. The results of the study were used to plot the effect of the gas phase content modulus of volumetric elasticity of working fluid at different pressures. It was also concluded that the obtained values describe the need to equip hydraulic drives with devices for degassing working liquids.

This article focuses on the method of balancing the pump jack and optimizing its operation. In the course of the work, the main balancing methods were considered and a method based on changing the balancing value by moving the movable carriage was proposed. In the course of the work, a model was developed that made it possible to simulate loads, the results of which determined the effectiveness of the proposed balancing method. Based on the results of the study, a graph of the change in torque when the support is located during the operation of the drive was built. Based on the results of the work, the corresponding conclusion was made.

The publication presents the results of research into the strength of an improved tank container. The tare of a tank container can be reduced through application of composite material for the tank. In this case its mass can be 46% lower than that of a metal tank. The strength of the tank was calculated by computer simulation. The maximum stress occurs in its lower part and is about 295 MPa.

Smoking is a potentially causal behavioral risk factor for type 2 diabetes (T2D), but not all smokers develop T2D. It is unknown whether genetic factors partially explain this variation. We performed genome-environment-wide interaction studies to identify loci exhibiting potential interaction with baseline smoking status (ever vs. never) on incident T2D and fasting glucose (FG). Analyses were performed in participants of European (EA) and African ancestry (AA) separately. Discovery analyses were conducted using genotype data from the 50,000-single-nucleotide polymorphism (SNP) ITMAT-Broad-CARe (IBC) array in 5 cohorts from from the Candidate Gene Association Resource Consortium (n = 23,189). Replication was performed in up to 16 studies from the Cohorts for Heart Aging Research in Genomic Epidemiology Consortium (n = 74,584). In meta-analysis of discovery and replication estimates, 5 SNPs met at least one criterion for potential interaction with smoking on incident T2D at p

Beginning in the Middle Palaeolithic, human populations penetrated areas of Central Asia that are today characterised by extremely arid conditions. Mongolia's Gobi Desert comprises one such region. Tsagaan Agui Cave presents an example of the later Pleistocene occupation of this area, containing stratified evidence of diachronic, intense human and animal occupation. Keywords: Mongolia, Gobi Desert, Tsagaan Agui Cave, Palaeolithic, cave archaeology, Introduction Tsagaan Agui Cave, located in the Gobi Altai Mountains of Bayankhongor Province in southern Mongolia (44[degrees]42'53.3' N, 101[degrees] 10'13.4' E; Figure 1), was first investigated in 1987-1989 and subsequently [...]

Abstract All-dielectric nanophotonics opens a venue for a variety of novel phenomena and scattering regimes driven by unique optical effects in semiconductor and dielectric nanoresonators. Their peculiar optical signatures enabled by simultaneous electric and magnetic responses in the visible range pave a way for a plenty of new applications in nano-optics, biology, sensing, etc. In this work, we investigate fabrication-friendly truncated cone resonators and achieve several important scattering regimes due to the inherent property of cones—broken symmetry along the main axis without involving complex geometries or structured beams. We show this symmetry breaking to deliver various kinds of Kerker effects (generalized and transverse Kerker effects), non-scattering hybrid anapole regime (simultaneous anapole conditions for all the multipoles in a particle leading to the nearly full scattering suppression) and, vice versa, superscattering regime. Being governed by the same straightforward geometrical paradigm, discussed effects could greatly simplify the manufacturing process of photonic devices with different functionalities. Moreover, the additional degrees of freedom driven by the conicity open new horizons to tailor light-matter interactions at the nanoscale.

One of the modern and widely used biotechnological methods for increasing the efficiency of animal reproduction is oestrus synchronization, which allows to reduce economic costs significantly. Using this method, a slight increase in the cost of processing animals is compensated by a significant decrease in labour costs, an increase in the technological efficiency of insemination and parturition, and the absence of costs for maintaining teasers. As a result, direct costs for reproduction might be reduced by a total of 50–60%. Induction and synchronization of sexual heat in goats have been used since the 1970s of the 20th century, however, in our country, such a biotechnological method of regulating reproductive function is just beginning to be practised, but the results of such implementations are not available in the literary sources. Therefore, the goal of our research was to determine the effectiveness of oestrus induction and synchronization in goats under specific farm conditions in Ukraine. The experiments were conducted between April 2021 and February 2022 in "Agrosvit" dairy farm in Shestakove village, Chuguyiv district, Kharkiv region, on goats of Alpine and Zaanen breeds, aged 2‒4 years, with a live weight of 35–55 kg. A total of 368 goats having ≤ 1 litre of milk production starting from the 180th day of lactation, were involved in this trial. The synchronization protocol included the insertion of an intravaginal sponge with progestogen (day 0) (Chronogest CR polyester-polyurethane vaginal sponge, 20 mg of chronolone, intravaginally), injections of prostaglandin (Oestrophan, 0.2 ml, intramuscularly), and chorionic gonadotropin (Sergon, 500 OD, 1 ml, intramuscularly) (day 9), removal of the progesterone sponge (day 11), detection of heat (day 12) and insemination (day 13). Pregnancy diagnosis was determined by ultrasound examination on day 40 after artificial insemination. In our studies, using an oestrus induction and synchronization protocol based on progestogen sponge, prostaglandin and chorionic gonadotropin, 93.7% of treated goats were inseminated with a fertility rate of 158.9%. According to the results of the study, it can be concluded that oestrus induction and synchronization in goats is an effective biotechnological technique that allows increasing the efficiency of the use of genetic resources of high-value animals significantly, to increase the scale of their participation in the process of reproduction of livestock while maintaining a high level of physiological functions of the reproductive system. In particular, such studies will help to determine the most appropriate oestrus synchronization protocol and to better understand the effect on sexual behaviour and hormonal influence, and to inseminate goats at the most optimal time, in a short time, with a shortened period of kidding.

Modern video surveillance systems (VSS) can recognize a person and her/his activity. A particular example of such a VSS system is the monitoring and support of human health and wellbeing during exercise with sports equipment. In this work-inprogress paper, a prototype of the VSS system is demonstrated for monitoring the movement of a person around the sport training machine. For the recognition problem we consider the following situations: a) training machine is free (no person is close to the machine); b) a person is in the area near the training machine (but not in the working area); c) a person is in the working area of training machine (but the training machine is not used); d) a person is working on the training machine. Our early experimental study evaluates the feasibility of such a VSS system.

A hexanucleotide repeat expansion in C9ORF72 is the most common genetic cause of ALS and FTD. Here, the authors demonstrate CRISPR/Cas9 excision of the expansion results in a rescue of disease mechanisms in vivo and in vitro.

We explore the dynamics of an adiabatic neural cell of a perceptron artificial neural network in a quantum regime. This mode of cell operation is assumed for a hybrid system of a classical neural network whose configuration is dynamically adjusted by a quantum co-processor. Analytical and numerical studies take into account non-adiabatic processes as well as dissipation, which leads to smoothing of quantum coherent oscillations. The obtained results indicate the conditions under which the neuron possesses the required sigmoid activation function.