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We consider a tubular membrane whose mechanical behavior is defined by a strain energy density function that combines the neo-Hookean model with the Demiray model. Both, the neo-Hookean and the Demiray models are isotropic material models, which found their application in the modeling of the mechanical behavior of biological soft tissue. This tubular membrane is subjected to an inner pressure, an axial stretch, and a change in the material volume due to swelling or deswelling. The interplay between the cylinder geometry and the loading conditions and different instability modes, namely, bulging bifurcation, bending bifurcation, and prismatic bifurcation, are studied. It is shown that a change in the material volume has a strong effect on the occurrence of these bifurcation modes because a change in the material volume may stabilize the cylinder against a particular bifurcation mode and may trigger another bifurcation mode at the same time. Despite the restriction to isotropic material behavior, this article shows that the material response to pressure, axial stretch, and material volume change is quite complex. [ABSTRACT FROM AUTHOR]

Permafrost, known for its high sensitivity to climate change and human activities, plays a crucial role in comprehending the environmental sustainability of Arctic cities. Yakutsk, being the largest city situated in continuous permafrost, has suffered irreversible damage to surface buildings due to the widespread permafrost thaw. Therefore, it is imperative to conduct detailed monitoring and assessment of surface deformation to ensure the stable operation of building facilities and to plan urban development situated above the permafrost. This study utilized 138 scenes of Sentinel‐1B images captured between 2017 and 2021 to process the surface deformation variations of Yakutsk using the Persistent Scatterer Interferometric Synthetic Aperture Radar (PS‐InSAR) method. The surface deformation rate map reflects that the study area is undergoing extensive surface subsidence. The cumulative deformation time series maps effectively trace the temporal and spatial evolution of surface deformation, with the highest surface subsidence rates exceeding 40 mm/year and maximum cumulative subsidence exceeding 250 mm. In‐depth analysis of the obtained results indicated that the permafrost in Yakutsk is undergoing degradation, and the primary reason for surface subsidence is the thawing of foundation soils and the degradation of ice‐bearing permafrost. This study provides basic data for the investigation of geohazards caused by surface subsidence in Yakutsk. [ABSTRACT FROM AUTHOR]

This research aimed to investigate the morphological changes of sandy soils with a varying number of freeze-thaw cycles (FTCs). The primary objective was to characterize the changes in particle morphology and establish the relationship between the number of FTCs and these changes. Two variables, namely the amount of variation and the coefficient of variation, were introduced as parameters to characterize the morphological changes of sandy soils. Statistical analysis was performed using the PIP9.1 particle dynamic image analyzer to quantify the morphological characteristics of sandy soil particles. The results showed that the five morphological characteristic parameters of sandy soil particles conformed to a normal distribution. The particle shape was primarily blocky, and sandy soil particles appeared more broken and regular in shape with an increase in the number of FTCs. The coefficients of variation of particle filling exhibit "conjugate" changes with other indicators, and the coefficients of variation of each indicator decrease gradually with an increase in the number of FTCs. Principal component analysis was employed to integrate information on sandy soil particle shape, resulting in a new index that established the relationship between the index and the number of FTCs. The findings of this study provide a better understanding of the morphological changes in sandy soils under freeze-thaw conditions and offer insight into the stability of sandy soils under these conditions. [ABSTRACT FROM AUTHOR]

Linear engineering facilities, such as gas transportation systems, extend from 30 to 500 metres in width and several hundred kilometres in length. Such routes pass through areas characterized by sufficiently diverse engineering, geological, geocryological and seismotectonic conditions. The safe and reliable functioning of gas transportation systems is ensured by their regular monitoring to prevent the development of hazardous exogenous geological processes. In particular, when monitoring ice formation, the greatest efficiency can be achieved by using unmanned aerial vehicles for low-altitude aerial surveys. In this research, remote sensing methods based on unmanned technologies were applied to assess the aufeis hazard in a section of the Power of Siberia gas pipeline in South Yakutia. The authors’ successful experience of using unmanned systems during an aeromagnetic exploration of iron ore deposits in South Yakutia was also considered. A series of studies, including georadar and electrical exploration profiling, as well as thermal imaging and high-resolution aerial photography by an aerial complex, was conducted to assess the dynamics of ice development over time in the area under study and to establish the signs of a developing hazardous process.

We demonstrate that strong elastic pump wave pulses soften sandstone more in humidified conditions than they do in dry conditions and that this effect is repeatable and reversible. We assess these changes via the non-linear interactions of a strong pump wave with a weaker probe wave. We find that there is an exponential time constant (τ ≈ 13 days) associated with this process that is independent of the amplitudes of the pump and the probe, the phase delay between the two waves (the time between transmission of the pump and probe waves), the sampling rate, and whether the sample is being dried or humidified. We demonstrate that the humidity-dependent differences in the amount of softening are induced by only a very small amount of absorbed water vapor and argue that this water is intercalated within clay particles. We also show that our pump–probe experiments detect these humidity-dependent differences in the amount of softening easily and repeatably using an experimental design that does not rely on resonance conditions. This means that, in principle, our experiments could be more easily generalized to other experimental geometries to investigate non-linear elastic properties in complex or irregular sample geometries. Our method and findings have potential relevance in oil and gas exploration, civil engineering, and understanding of the mechanism of earthquakes. [ABSTRACT FROM AUTHOR]

Residual stress may have an important influence on the mechanical response of residually stressed materials. This paper is concerned with the effects of residual stress on the stability of inflated, axially extended, residually stressed circular cylindrical tube. To this end, the theory of small incremental deformations superimposed on a large underlying finite deformation is used. Asymmetric and axisymmetric types of bifurcation are considered. It is found that for residual stress parameter γ of the same sign the effect of the residual stress is different depending on the type of bifurcation. For example, for asymmetric bifurcations with mode number m = 1 and with positive γ inclusion of residual stress makes the tube more stable, on the other hand, for axisymmetric bifurcations inclusion of residual stress, corresponding to positive residual stress parameter γ, leads to increase of instabilities. In all cases, residual stress with positive and negative residual stress parameter γ leads to a symmetric character of bifurcation curves. [ABSTRACT FROM AUTHOR]

This paper is devoted to the evaluation of the hardware resources of computer systems for solving a computationally expensive problem such as the calculation of the probability distributions of statistics by the second multiplicity method based on Δ -exact approximations of samples with a size of 320–1280 characters and an alphabet power of 128–256 characters. The accuracy is Δ = 10 − 5 and the total solution time should not exceed 30 days or 2.592 × 10 6 seconds for 24/7 computing. Owing to the use of the properties of the second multiplicity method, the computational complexity of the calculations can be brought within the range of 9.68 × 10 22 − 1.60 × 10 52 operations with the number of tested vectors at 6.50 × 10 23 − 1.39 × 10 50 . The solution of this problem for the specified parameters of samples during the given time requires hardware resources which cannot be provided by modern computer technology such as processors, graphics accelerators and programmable logic integrated circuits. Therefore, in this paper, we analyze the possibilities of promising quantum and photon technologies for solving the problem with the given parameters. The main advantage of quantum computer systems is the high speed of calculations for all possible parameter values. However, quantum acceleration will not be achieved to calculate the probability distributions of statistics due to the need to check all the obtained solutions. Here, the number of obtained solutions corresponds to the dimension of the problem. In addition, due to the current development level of quantum hardware components, it is impossible to create and use 120 qubit quantum computers for the solution of the considered problem. Photon computers can provide high computation speeds at low power consumptions and require the smallest number of nodes to solve the considered problem. However, unsolved problems with the physical implementation of efficient memory elements and the lack of available hardware components make the use of photon computer technologies impossible for calculating the probability distributions of statistics in the near future (5–7 years). Therefore, it is most reasonable to use hybrid computer systems containing nodes of different architectures. To solve the problem on various hardware platforms (general purpose processors, GPUs and FPGAs) and configurations of hybrid computer systems, we suggest to use the architecture-independent high-level programming language SET@L. The language combines the representation of calculations as sets and collections (based on the alternative set theory of P. Vopenka), the absolutely parallel form of the problem represented as an information graph and the paradigm of aspect-oriented programming. [ABSTRACT FROM AUTHOR]