Explosion welding of large-scale bimetallic plates remains a major unresolved challenge in the nuclear industry, petrochemical engineering, power generation, shipbuilding, and other sectors, mainly owing to the increased formation of melted regions and structural inhomogeneities that reduce joint strength. These issues are associated with cumulative and shock-wave processes occurring in the gap between the plates before collision. As the plate dimensions increase, both the exposure time of the plate surfaces to the high-temperature shock-compressed gas (SCG) formed in the gap and the amount of dispersed metal particles injected into the gap through cumulative effects become more significant, thereby affecting the SCG parameters. In this study, low-inertia thermoresistive sensors (RTDs) with high spatial resolution were used to measure high-intensity heat fluxes generated by the two-phase flow of gas saturated with dispersed metal particles during explosion welding of copper and steel plates under a wide range of conditions, including variations in plate dimensions and welding regimes (with and without cumulative jet formation). The results show that cumulative processes associated with the high-velocity flow of dispersed metal particles in the gap determine the nonuniform distribution of heat flux along the SCG region. Maximum values (up to 5 GW/m2) are reached near the collision point, the flux stabilizes at approximately 0.1 GW/m2 in the central region, and increases to approximately 0.7 GW/m2 at the shock-wave front. Despite the asymmetry of the cumulative particle flow across the gap height, the thermal effect of the SCG on the flyer and base plates was found to be the same. A twofold increase in plate length (from 0.28 to 0.55 m) leads to a fourfold increase in the heat flux in the central part of the SCG region (from 0.04 to 0.16 GW/m2). The novelty of this research lies in the fact that, for the first time, a dual influence of cumulative effects has been identified: the particles cool the SCG, reducing the heat flux compared to the regime without cumulative jet formation, while the additional momentum transfer from the particles to the gas accelerates the shock wave front (from 1.09 to 1.3–1.4 Vc) and prolongs the duration of thermal exposure.
Molecular dynamics is a powerful tool to investigate the properties of fluid systems. However, a correct interpretation of the results of simulations is required. In particular, some simulations show appearance of large voids in liquids, which contradicts our common sense on what is liquid. At the same time, we are not aware of any publication that explains the origin of such voids or allows one to predict the thermodynamic conditions under which they appear. In the present paper we discuss the origin of large cavities in liquids in molecular dynamics simulations. We demonstrate that the cavities appear either if the temperature of the system is above the critical one of the liquid–gas transition or if the system is in two-phase liquid–gas region. The work is carried out in two steps. First, we study several well-known systems to demonstrate the appearance of cavities in supercritical fluids and in the liquid–gas two phase regions. We then perform simulations of systems in which voids have been previously reported but their origin remained unidentified, and we demonstrate that the behavior of these systems is equivalent to that of the well-known cases. These results allow us to predict the densities and temperatures at which cavities can be expected. We also show that NVT and NPT ensemble molecular dynamics simulations behave differently in the liquid–gas two-phase region.
Computer vision is becoming a core technology in PLF, enabling non-contact monitoring, phenotyping, and decision support at both animal and group levels. This umbrella review synthesised review-level evidence from 112 reviews on cattle, pig, and poultry systems, covering visual applications for identification, phenotyping, health, behaviour, locomotion, body condition, growth, reproduction, mortality, and resource use. To preserve the review as the bibliographic unit while capturing multi-topic evidence, multi-label coding generated 328 review-domain assignments across six PLF computer vision domains. Health/stress and posture/activity were the most frequently reviewed areas; however, these patterns reflect review coverage rather than evidence strength. Benchmarking reporting averaged 11.09 out of 14 criteria, corresponding to 79.2%, but validation-critical items, including class balance, annotation protocols, validation splits, and farm or site reporting, remained less complete. Methodological confidence was limited: AMSTAR 2 classified 95 reviews as critically low and 17 as moderate, while ROBIS classified 78 as high, 17 as unclear, and 17 as low risk of bias. The corpus-level candidate-reference overlap estimate was 0.122% and is retained only as a sensitivity estimate, not as formal primary-study CCA or evidence of independence. Review-derived performance and readiness tiers identified a mean descriptive performance-to-deployment gap of 0.63 across 328 assignments. Overall, reported model performance continues to exceed documented farm-deployment evidence, highlighting the need for stronger external validation, transparent benchmarking, workflow integration, economic assessment, and user-readiness evidence before routine deployment claims can be supported.
A high-sensitivity temperature sensor based on two parallel-connected in-line Michelson interferometers (MIs) and the Vernier effect is proposed and demonstrated. Each MI is a segment of a specially designed inner-cladding fiber spliced with a lead-in fiber. The interference occurs between the core and cladding modes of inner-cladding fiber. Due to the special waveguide properties of the inner-cladding fiber, the 3 mm-long MI exhibits a regular reflection spectrum with a low free spectral range (FSR) of approximately 9 nm. The high regularity and low FSR of individual interferometer allows us to obtain a superimposed spectrum with a clearly defined envelope, calculated using approximately two dozen points. The temperature sensitivities of a single MI and the Vernier temperature sensor were measured to be 54.29 ± 0.22 pm/°C (in the temperature range of 23–200 °C) and 1.012 ± 0.017 nm/°C (in the temperature range of 23–160 °C), respectively. Due to the high sensitivity of the individual interferometer, an enhanced sensitivity of the Vernier sensor was achieved with an average amplification factor of M = 18.7.
