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The perforated paper honeycomb structure with double-hole in cell walls is one kind of innovative sandwich structure also to improve drying process of traditional honeycomb paperboard. Based on the analytical calculation, experiment inspection and finite element analysis, this paper is focus on the paper honeycomb core layer with double-hole in cell walls, and especially studies the bending and folding deformation and the compressive strength under out-of-plane quasi-static compression for different humidity. The structure first appears elastic buckling and folds near the circular holes in the cell wall, and goes on buckling, folding and crushing until to the densification with the continuously increase of compression set. Its quasi-static compressive stress and strain curve mainly shows four kinds of compression deformation processes, such as linear elastic stage, elastic yielding stage, plastic collapse stage, and densification stage. The critical stress and plateau stress of the structure slowly decrease with the increase of humidity and aperture, and the multiple linear regression analysis result illustrates that the relative humidity has much more influence on the critical stress and plateau stress. For different humidity and aperture, the analytical calculation result is close to the experiment result. However, the finite element simulation result greatly deviates from the above two results, especially for relative humidity 50% and 60% cases. [ABSTRACT FROM AUTHOR]

Cement stabilization is a widely applied technique in improving the workability and geotechnical properties of soft clay. This paper investigated the influence of cement stabilization on the soil–water characteristic curve (SWCC) and the deformation behavior of unsaturated cement–stabilized soft clay. The combined effect of cementation and partial saturation on the hydromechanical behavior of cement-stabilized soils was discussed. The SWCC of stabilized soil was measured in the full suction range under drying and wetting paths using the pressure plate method, the filter paper method, and the vapor equilibrium technique. The deformation behaviors of cement-stabilized soft soil were investigated by conducting suction-controlled oedometer tests. Furthermore, scanning electron microscope micrographs and mercury intrusion porosimetry tests were performed to investigate the effects of cement content on the evolution of soil pore structures. The test results showed that the water retention capacity of the stabilized soft clay increased with increasing cement content. The SWCC showed a significant hysteretic behavior in the boundary effect zone and transition zone, whereas the hysteretic effect was unapparent in the residual zone. The increased cement content had a more significant hysteretic effect on the SWCC. The deformation resistance capacity increased as the cement content and matric suction increased. However, the effect of matric suction on deformation resistance capacity decreased as the cement content increased. With the increase in cement content, the macropores were converted to small interaggregate pores, the pore spaces were distributed more uniformly, and the particle surface became rougher, resulting in higher water retention capacity and significant hysteresis of the SWCC. [ABSTRACT FROM AUTHOR]

Paper honeycomb and EPE are widely used in the field of packaging protection and safety transportation. Given the cushioning and protective function of unilateral and bilateral composite layered structures (CLSs) including polyethylene foam (EPE) and paper honeycomb, this work focused on analyzing the energy absorption (EA) and compression deformation of honeycomb thickness (HT) CLS under diverse drop impact (DI) status. Experimental observation showed that the increase of HT can improve the impact resistance of EPE and its CLSs. For the CLS with the HTs of 10, 15, 20, and 25 mm, the increase of paper HT may reduce the EA at low impact energy, while enhancing the EA capability at high impact energy. However, the EA of CLSs with a large HT of 70 mm is relatively poor. For the same drop weight mass or impact energy, the stroke efficiency (SE) and specific energy absorption (SEA) of the unilateral CLS with the same HT are, respectively, increased by 39.1% and 16.2%, so the EA of the unilateral CLS is superior to the bilateral CLS. [ABSTRACT FROM AUTHOR]

This study introduces the opinion of the corrugation hierarchy to develop the second-order corrugation paperboard, and explore the deformation characteristics, yield strength, and energy absorbing capacity under out-of-plane static evenly compression loading by experimental and analytical approaches. On the basis of the inclined-straight strut elements of corrugation unit and plastic hinge lines, the yield and crushing strengths of corrugation unit were analyzed. This study shows that as the compressive stress increases, the second-order corrugation core layer is firstly crushed, and the first-order corrugation structures gradually compacted until the failure of entire structure. The corrugation type has an obvious influence on the yield strength of the corrugation sandwich panel, and the yield strength of B-flute corrugation sandwich panel is wholly higher than that of the C-flute structure. At the same compression rate, the flute type has a significant impact on energy absorption, and the C-flute second-order corrugation sandwich panel has better bearing capacity than the B-flute structure. The second-order corrugation sandwich panel has a better bearing capacity than the first-order structure. The static compression rate has little effect on the yield strength and deformation mode. However, with the increase of the static compression rate, the corrugation sandwich panel has a better cushioning energy absorption and material utilization rate. [ABSTRACT FROM AUTHOR]

In this paper, the characteristics of special stamping process requirements and the shortcomings of existing application technology are studied. Through repeated motion simulation analysis and size optimization calculation, a kind of inertia-controlled molding press is proposed to make up for this technical vacancy. This paper first describes the working principle and structure scheme of the main transmission mechanism of the inertia-controlled molding press. With the help of Adams-View x64 2013, the main transmission mechanism is simulated and analyzed from the aspects of kinematics and dynamics, and a physical prototype is made to test the key reliability indexes of the main transmission mechanism. According to the test data, the static strength, stiffness, vibration characteristics, and dynamic characteristics of the 200 t inertia-controlled molding press are evaluated, which provides a reference for the design of this kind of machine tool. [ABSTRACT FROM AUTHOR]

The propulsion system for an aircraft is one of its most crucial systems; therefore, its reliable work must be ensured during all operational conditions and regimes. Modern materials, techniques and methods are used to ensure this goal; however, there is still room for improvement of this complex system. The proposed manuscript describes a progressive approach for the mechanical properties prediction of the turbine section during jet engine operation using an artificial neural network, and it illustrates its application on a small experimental jet engine. The mechanical properties are predicted based on the measured temperature, pressure and rpm during the jet engine operation, and targets for the artificial neural network are finite element analyses results. The artificial neural network (ANN) is trained using training data from the experimental measurements (temperatures, pressure and rpm) and the results from finite element analyses of the small experimental engine turbine section proposed in the paper. The predicted mechanical stress by ANN achieved high accuracy in comparison to the finite element analyses results, with an error of 1.38% for predicted mechanical stress and correlation coefficients higher than 0.99. Mechanical stress and deformation prediction of the turbine section is a time-consuming process when the finite element method is employed; however, the method with artificial neural network application presented in this paper decreased the solving time significantly. Mechanical structural analyses performed in ANSYS software using finite element modeling take around 30–40 min for one load step. In contrast, the artificial neural network presented in this paper predicts the stress and deformation for one load step in less than 0.00000044 s. [ABSTRACT FROM AUTHOR]

The permeability coefficient and air-entry value of saturated soil are important hydraulic properties, which play an important role in engineering applications. Subsoil supporting foundation is subjected to stress and undergoes deformation; the saturated permeability coefficient of such deformed soil is of practical importance. With the help of fractal theory, based on the different fractal forms of Tao–Kong model, CCG model, Mualem model, and soil–water characteristic curve, this paper derives the saturated permeability coefficient models under four deformation conditions, considering the saturation permeability coefficient is inversely proportional to the square of the air-entry value and directly proportional to the square of the maximum aperture of the soil. Combining the prediction method of air-entry value under deformation conditions, four prediction methods for the permeability coefficient of deformed saturated soil are established and the method proposed in this paper is validated by the measured value of the saturated permeability coefficient of the deformed soil. As observed, the predicted values of the four methods for clay, silt loam, sandy loam and sandy soil under deformed conditions are in acceptable agreement with the measured values, and the prediction results of the second prediction method are the closest to the measured values. [ABSTRACT FROM AUTHOR]

An excavator is an off-road vehicle or machine used for several types of construction activities. It has an attachment called a backhoe that is widely used for digging. While digging the earth's massive force works on bucket tips and may bring deformation in it. In this paper an attempt is made to quantify the value of the variables obtained while the all-attached backhoe is considered as a multibody, given in rotation to each joint and simulated in Ansys. The results obtained show that the deformation obtained is small at low rotation and large at high rotation rate. Comparison of the deformation, joint forces and velocity at each set of rotation has been tabulated in x, y and Z directions as well as the overall velocity, total joint force and deformation has also been calculated. This paper provides the base to study and design a multibody system which may undergo deformation so that the end effect may be obtained precisely as required in precision tools and machinery. [ABSTRACT FROM AUTHOR]

Accurate prediction of excavation deformation and stress affects the safety of excavation engineering and the surrounding environment. However, the traditional calculation method ignores the influence of soil shear action and its nonlinear deformation characteristics. Therefore, this paper proposed a coupled analytical method for braced excavation considering the continuity of soil deformation and nonlinear pile–soil interaction. A nonlinear Pasternak two-parameter foundation model was developed based on the Pasternak foundation model and nonlinear p–y curves. The control differential equations for the excavation in the critical and embedded sections were derived. Also, the numerical solutions of excavation deformation and force under different boundary conditions were obtained by the finite difference method and Newton's iteration method. Further, the excavation calculation procedure considering the construction process and nonhomogeneity of soil was suggested. Through finite-element (FE) and engineering case analyses, the traditional calculation method overestimated the excavation deformation and internal force, while the proposed methods were consistent with the measured results. Finally, the effects of soil shear stiffness and initial foundation reaction modulus on the excavation were discussed, and we found that the two parameters had more significant impact on the wall bending moment than displacement. The results provide some reference for the design calculation of braced excavation. [ABSTRACT FROM AUTHOR]

In the fractured weak fault zone, rock mass exhibits low strength and poor self-stability. The geological conditions are complex, and when tunnels cross through fractured zones, significant deformations and collapses are prone to occur, leading to geological hazards. This paper investigates the in situ stress and deformation patterns of the Dongmachang Tunnel No. 1, proposing support solutions for addressing tunnel deformations through field experiments and numerical simulations. The on-site monitoring results indicate that despite implementing measures such as grouting reinforcement and temporary steel supports to control surrounding rock deformation, significant structural damage still occurred in the tunnel support system. The manifestations included severe sinking and cracking of the arch crown, strong inward deformation of the sidewalls, widespread cracking, crushing, and spalling of shotcrete, slight arching uplift, and severe distortion and twisting of steel arches forming a "Z" or "S" shape. To ensure tunnel safety and control the stability of excavations in weak fault zones, a comparison of tunnel deformation support schemes is conducted through field experiments and numerical simulations, indicating that replacing the upper tunnel structure and invert can effectively prevent tunnel deformations. These measures are vital for the sustainable development of tunnel. [ABSTRACT FROM AUTHOR]

The goal of the present paper is to provide a cohomology theory and crossed modules of modified Rota–Baxter pre-Lie algebras. We introduce the notion of a modified Rota–Baxter pre-Lie algebra and its bimodule. We define a cohomology of modified Rota–Baxter pre-Lie algebras with coefficients in a suitable bimodule. Furthermore, we study the infinitesimal deformations and abelian extensions of modified Rota–Baxter pre-Lie algebras and relate them with the second cohomology groups. Finally, we investigate skeletal and strict modified Rota–Baxter pre-Lie 2-algebras. We show that skeletal modified Rota–Baxter pre-Lie 2-algebras can be classified into the third cohomology group, and strict modified Rota–Baxter pre-Lie 2-algebras are equivalent to the crossed modules of modified Rota–Baxter pre-Lie algebras. [ABSTRACT FROM AUTHOR]

Accurately characterizing permanent deformation in granular materials subjected to cyclic loading is crucial for pavement design. This paper introduces an alternative approach to characterizing permanent deformation in a framework that reduces the number of load cycle repetitions by applying an alternative analytical strategy based on plastic strain rate variation over time. The methodology uses a cycle-hardening approach to establish correlations between short-term (post-compaction) and long-term (shakedown state) plastic strain accumulation. This alternative approach provides an efficient means to accelerate the characterization of permanent deformation, ensuring the integrity and validity of the assessment in a more time-efficient and resource-optimized way. [ABSTRACT FROM AUTHOR]

The utilization of baffle structures as a highly effective strategy for mitigating debris flow has attracted significant scholarly attention in recent years. Although the predominant focus of existing research has been on augmenting the energy dissipation capabilities of baffle structures, their deformation behavior under impact load has not been extensively investigated. Addressing this research gap, the current study systematically designs a series of physical model experiments, incorporating variables such as baffle height, shape, and various combinations of baffle types to comprehensively analyze the deformation characteristics of baffles subjected to debris flow impact. The experimental results reveal that the deformation of baffle group structures demonstrates a marked non-uniform spatial distribution and exhibits a latency effect. Additionally, distinct baffle configurations show considerable variations in peak strain, suggesting that combining different baffle shapes can not only optimize energy dissipation but also enhance resistance to deformation. Moreover, the relationship between baffle height and the development of deformation in relation to energy dissipation capacity is inconsistent, indicating that deformation must be a key consideration in the design of baffle structures. Consequently, this paper advocates for the formulation of a deformation-based design strategy for baffle structures, with the findings presented herein providing a foundational reference for future studies. [ABSTRACT FROM AUTHOR]

This paper uses a finite volume algorithm to address the numerical modeling of fluid flow around moving bodies. The Navier–Stokes equations, which describe the flow of viscous compressible gas, along with key boundary conditions and discretization schemes, are presented. As the motion of boundaries typically leads to changes in the control volumes, the basic discretization schemes need to be adapted. This paper provides a detailed discussion on the adaptation of the initial system to deforming boundaries while preserving communication topology. The method for calculating the boundary velocity is a crucial element of the numerical scheme. The paper proposes an approach to reconstruct the boundary velocity vector using deformation analysis and the condition of geometric conservation. This approach ensures correct simulation results for arbitrary unstructured computational grids. A comparison of two approaches to reconstructing the boundary velocity vector for characteristic aviation problems in the direct formulation is presented. It is shown that the proposed approach allows for more accurate modeling of object motion on arbitrary grids using the "invariant" principle of the computational domain topology. [ABSTRACT FROM AUTHOR]

The appearance and development of new construction materials, technology and accurate geodetic instruments have led to the necessity of their inevitable use in the health monitoring, maintenance, and restoration of civil structures and special structures such as high-rise cooling towers. This paper presents an accurate practical and analytical method for determining the structural deformation and axis inclination of high rise cooling towers using terrestrial laser scanner (TLS) observations through the projection of tower surface points coordinates on a vertical plane. Four cooling towers in El-Mahla El-Kubra city, Egypt are observed and studied. Two of them with height 56 m, and the others were 36 m height. The studied four towers have different cross-section diameters along the tower height. Each tower has a cone shape with a curved wall. The equation of the tower wall is determined using TLS observations and least squares adjustment techniques. The equations of cone projection with a curved wall are derived and presented in this paper. From TLS observations, the radii and accuracy of each 2 m tower height are determined with center coordinates, and then the inclination of the tower axis is calculated and drawn. From the results of TLS observations, data processing, and analysis using the suggested techniques, it is deduced that there is a deformation in tower walls with small values. The specified technique for observations collection and TLS data analysis through projection on a vertical plane is significant and valuable for determining the structural deformation of circular high rise buildings and towers. From the results, there are obvious deformation values in some cooling towers, so maintenance work must be included. The towers also must be checked and monitored several times at brief intervals. [ABSTRACT FROM AUTHOR]

Aiming at the problems of large elastic deformation and low machining accuracy in cutting titanium alloy thin-walled parts, this paper establishes the finite element model of milling titanium alloy thin-walled parts, and simulates and analyses the milling process of titanium alloy thin-walled parts by the statics analysis module of ANSYS 15.0 software. The maximum deformation point of the workpiece in the milling process is determined. Then the combination of cutting parameters that can minimize the deformation is determined by the orthogonal experiments of four factors and four levels. This paper designs the single factor experiments, which study the distribution of the milling force and the deformation law of the parts in the milling process. Moreover, this paper carries out the optimal design of the cutting parameters by orthogonal experiments, which provides a reference for the selection of the cutting parameters for the bending thin-walled parts of titanium alloy. [ABSTRACT FROM AUTHOR]

This paper presents the analysis by the finite element method of the tensions and deformations produced in the mechanized support beams. The finite element method allows the analysis of physical phenomena that can be described with the help of mathematical models made up of systems of differential equations with initial and boundary conditions. From the results obtained in this paper, it was observed that the asymmetries with the greatest influence are those with respect to the vertical-longitudinal plane of the mechanized support [ABSTRACT FROM AUTHOR]

Artificial corner reflectors are widely used in the vegetated landslide for time series InSAR monitoring due to their permanent scattering features. This paper investigated the RCS features of a novel dihedral CR under multi-resource SAR datasets. An RCS reduction model for the novel dihedral corner reflector has been proposed to evaluate the energy loss caused by the deviation between the SAR incident angle and the CR's axis. On the Huangtupo slope, Badong county, Hubei province, tens of dihedral CRs had been installed and the TSX–spotlight and Sentinel-TOPS data had been collected. Based on the observation results of CRs with more than ten deviation angles, the proposed reduction model was tested with preferable consistency under a real dataset, while 2 dBsm of systematic bias was verified in those datasets. The maximum incident angle deviation in the Sentinel data overlapping area is over 12°, which leads to a 2.4 dBsm RCS decrease for horizontally placed dihedral CRs estimated by the proposed model, which has also been testified by the observed results. The testing results from the Sentinel data show that in high, vegetation-covered mountain areas like the Huangtupo slope, the dihedral CRs with a 0.4 m slide length can be achieve 1 mm precision accuracy, while a side length of 0.2 m can achieve the same accuracy under TSX–spotlight data. [ABSTRACT FROM AUTHOR]

In this paper, we define a cohomology theory of a modified λ -differential left-symmetric algebra. Moreover, we introduce the notion of modified λ -differential left-symmetric 2-algebras, which is the categorization of a modified λ -differential left-symmetric algebra. As applications of cohomology, we classify linear deformations and abelian extensions of modified λ -differential left-symmetric algebras using the second cohomology group and classify skeletal modified λ -differential left-symmetric 2-algebra using the third cohomology group. Finally, we show that strict modified λ -differential left-symmetric 2-algebras are equivalent to crossed modules of modified λ -differential left-symmetric algebras. [ABSTRACT FROM AUTHOR]

A multisubstructure-based method for assessing the deformation and stress of a fine-meshed model according to a coarse model was proposed. Integrating boundary conditions in a local fine-meshed model, a displacement mapping matrix from the coarse model to the fine-meshed model was constructed. The method was verified by a three-level panel in a fluid–structure interaction (FSI) framework by integrating the steady vortex lattice method (VLM). A comparison between the inner deformation distribution of the coarse model and that of the global fine-meshed model obtained from MSC.Nastran was carried out, and the results showed that the coarse model failed to demonstrate reliable strains and stresses. In contrast, the proposed method in this paper can effectively depict the inner deformation and critical stress distribution. The deformation error was lower than 8%, meeting engineering requirements. Moreover, the results of different working conditions can achieve a similar relative error of displacement for an identical position. The easy storage of the displacement mapping matrix and the convenience of the boundary information transformation among all substructure levels are prominent aspects. As a result, there is a solid foundation for addressing the time-dependent problem in spite of the simultaneity and region. [ABSTRACT FROM AUTHOR]

Environmental responses to deep excavations are combined results of numerous factors. The effects of some factors are relatively straightforward and can be considered carefully during the design. On the other hand, more features impact excavation-induced performances indirectly, making their influences difficult to be clearly understood. Unfortunately, the complexity and non-repeatability of practical projects make it impossible to thoroughly understand these issues through realistic deep excavation projects. Therefore, parametric studies based on repeatable laboratory and numerical tests are desired to investigate these issues further. This work examines the influence of several key features on excavation-induced displacements through a series of 3D numerical tests. The study includes the choice of soil constitutive models, the modeling method of the soil–wall interface, and the influences of various key soil parameters. The comparison shows that the MCC model can yield a displacement field similar to the HSS model, while its soil movement is greatly improved compared to the MC model. Both the soil–wall interface properties and soil parameters impact the excavation-induced displacement to a large extent. In addition, the influence mechanisms of these parameters are analyzed, and practical suggestions are given. The findings of this paper are expected to provide practical references to the design and construction of future deep excavation projects. [ABSTRACT FROM AUTHOR]

The prefabricated recyclable supporting structure (PRSS) is an innovative support system that integrates a steel skeleton with polymer waterproof technology. Earth berms are extensively adopted to support the PRSS, but there is limited understanding on the factors influencing their behavior in circular excavations. In this paper, a numerical model is first validated with a case history in Henan, China. Afterwards, the geometric parameters of the earth berms, including the height (H), the top width (B1), and the bottom width (B2), on the behavior of the PRSS, are investigated. It is shown that, by increasing the height, top width and bottom width of earth berms, the lateral deflections, and bending moments of supporting piles, as well as the ground surface settlements, tend to decrease. However, the reduction effect of these parameters diminishes as well. Moreover, the raised effective formation level considering the effect of the earth berms on stability and deformation analyses is discussed. The factor of the safety of the excavation is almost doubled when axisymmetric conditions are considered compared to plane strain conditions. In deformation analysis, the raised effective formation level increases with the height of the earth berms until a steady value is reached. [ABSTRACT FROM AUTHOR]

The Kumaun Himalaya is considered as the most active part of the Central Seismic gap in the Indian Sub-continent. In this paper, we presented active surface deformation rates of the Kumaun region from February 2017 to February 2021 using the Persistent Scatterer Interferometric Synthetic Aperture Radar (PSI) technique. The cumulative displacement that occurred during the span of 4 years is ±55 mm, whereas the Line of Sight (LOS) deformation velocity rate ranges is ±7 mm/yr. Apart from PSI, we also estimated the b-value of the Kumaun region from 1803 to 2021 (399 events) and its value is 0.54 ± 0.03. A distinct NE-SW trend of b-value is observed where earthquakes with M>6 occurred towards NE of this trend. The PSIderived deformation reveals that the central part of the Inner Lesser Himalaya along with the Main Central Thrust (MCT) zone is dominated by uplift. The zone between the Munsiari Thrust (MT) and MCT in the central region shows the maximum uplift ranging 5-7 mm/yr which exactly lies above the mid-crustal ramp of the Main Himalayan Thrust (MHT). Our results are well corroborated with available observations of geodetic strain and peak ground acceleration values. However, the deformation patterns and highvelocity rates in the central part of the study area between MT and MCT indicate the accumulation of high stress. [ABSTRACT FROM AUTHOR]

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The investigation of reactivated landslides in the alpine-canyon areas suffers the difficult accessibility of precipitous terrain. In particular, when reactivated landslides occur along the major roads, efforts are focused on measuring ground surface displacements during road construction. Nevertheless, the ancient landslide deposits may reactivate after several years of road operation, while they show a stable state during the road construction. The characterization of this type of reactivated landslides is challenging, due to their complex mechanism and the limited monitoring data. Appropriate multi-source data can provide insights into deformation fields and enhance the understanding of landslide mechanisms, ensuring the outperformance of remedial works. This paper reports a recent Tangjiawan reactivated landslide along the Wenchuan-Maerkang Highway in Li County, China. The outcomes, including satellite InSAR, in situ real-time monitoring, and detailed ground and UAV investigation, conducted at this landslide are presented. Early deformation of the reactivated landslide began from 2019, with an InSAR-derived velocity of −11.7 mm/year, furthermore, a significant subsidence of about 21.2 mm, which occurred within a span of only 12 days from 3 June 2020 to 15 June 2020, was observed. The deformation characteristics derived from in situ monitoring during the remedial works were likely firstly associated with the initial unreinforced slope condition and the heavy rainfall. Subsequently, the displacement evolution transformed into deformation induced by time-dependent reduction in slope strength under rainfall conditions. The existing of unconsolidated deposits derived from ancient landslides, along with a fragile geo-structure consisting of rock blocks and gravels interlayered with breccias, exacerbated by large relief created a predisposition for landslide reactivation. Furthermore, 13 days of antecedent cumulative rainfall totaling 224.5 mm directly triggered the occurrence of a landslide event. The significance and implications of integrating multiple monitoring techniques are emphasized. [ABSTRACT FROM AUTHOR]

Facial expression is an important way to reflect human emotions and it represents a dynamic deformation process. Analyzing facial movements is an effective means of understanding expressions. However, there is currently a lack of methods capable of analyzing the dynamic details of full-field deformation in expressions. In this paper, in order to enable effective dynamic analysis of expressions, a classic optical measuring method called stereo digital image correlation (stereo-DIC or 3D-DIC) is employed to analyze the deformation fields of facial expressions. The forming processes of six basic facial expressions of certain experimental subjects are analyzed through the displacement and strain fields calculated by 3D-DIC. The displacement fields of each expression exhibit strong consistency with the action units (AUs) defined by the classical Facial Action Coding System (FACS). Moreover, it is shown that the gradient of the displacement, i.e., the strain fields, offers special advantages in characterizing facial expressions due to their localized nature, effectively sensing the nuanced dynamics of facial movements. By processing extensive data, this study demonstrates two featured regions in six basic expressions, one where deformation begins and the other where deformation is most severe. Based on these two regions, the temporal evolutions of the six basic expressions are discussed. The presented investigations demonstrate the superior performance of 3D-DIC in the quantitative analysis of facial expressions. The proposed analytical strategy might have potential value in objectively characterizing human expressions based on quantitative measurement. [ABSTRACT FROM AUTHOR]

In excavation engineering, most of the retaining structures are subjected to asymmetrical loads, including in asymmetrical excavation and asymmetrical overloading. However, a theoretical solution to, and deformation-controlling method for, this problem has remained elusive to date. In this work, a semianalytical solution for determining the deformation of retaining structures subjected to asymmetrical loads was derived based on the principle of minimum potential energy. The retaining structures were viewed as flexible, and the overall deformation of the retaining system was evaluated by our proposed theoretical model. This model was verified by comparing it with practical monitoring data. Subsequently, the theoretical solution was applied to analyze the stress and deformation characteristics under the conditions of asymmetrical excavation and asymmetrical overloading, which can be controlled to ensure the safety of a project. Finally, because of the requirement for a small amount of deformation in the foundation pit retaining piles, the earth pressure on the retaining piles is close to the static earth pressure. Reducing the length of the retaining pile on one side had a greater influence on the deformation on that side, but less of an influence on the other side. Thus, the proposed model can be used for optimizing the asymmetrical design of a retaining structure in order to balance the economy and safety of a project. Our design theory can be applied to a variety of engineering projects. A typical case is the Guangzhou Baiyun District Comprehensive Transportation Hub Project in China. The method was used to analyze the status of the subway foundation pit, offering a new design scheme to reduce the design length of the retaining piles, which resulted in great economic benefits in its practical application. The findings provided in this paper can be applied to the engineering of any long, narrow foundation pit that can be simplified into a two-dimensional plane–strain calculation model, being used to realize more accurate deformation control over the foundation pit envelope. The core of this calculation method is that it can accurately describe the magnitude of the earth pressure. The distribution of the earth pressure is worthy of further study. [ABSTRACT FROM AUTHOR]

Deep excavations clearly impact adjacent existing properties and threaten their operational safety. Predicting the deformation of existing infrastructure induced by nearby underground construction is the main concern of urban underground development. This paper presents an analytical calculation method for predicting underground pipe gallery deformations induced by adjacent deep excavations. First, the authors assume the existing pipe gallery to be nonexistent in the soil and propose a solution to calculate the excavation-induced vertical movements of the soil at the position of the existing pipe gallery. Thereafter, the authors simplify the existing pipe gallery as an elastic beam on a Winkler foundation to calculate its deformation. Finally, the method is verified by the good agreement found between the calculated result and the field measurement of the construction of the Shanghai Hongqiao CBD project. The proposed analytical method of this work can provide accurate evaluation results for similar engineering projects. [ABSTRACT FROM AUTHOR]

Despite the profound roles of surface deformation monitoring techniques in observing permafrost surface stability, predetermining the approximate location and time of possibly occurring severe permafrost degradation before applying these techniques is extremely necessary, but has received little attention. Taking the oil tank collapse accident in the Norilsk region as a case, we explored this concern by analyzing the permafrost deformation mechanisms and determining early surface deformation signals. Regarding this case, we firstly applied the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique to obtain its permafrost surface deformation rate, then utilized a sine model to decompose its interannual deformation and seasonal deformation, and finally compared the relationship between the topographic slope and deformation rate. Based on experimental results, we reveal that when the annual average temperature continuously increases at a rate of 2 ° C/year for 2∼3 consecutive years, permafrost areas with relatively large topographic slopes (>15 ° ) are more prone to severe surface deformation during the summer thaw period. Therefore, this paper suggests that permafrost areas with large topographic slopes (>15 ° ) should be taken as the key surveillance areas, and that the appropriate monitoring time for employing surface deformation monitoring techniques should be the summer thawing period after a continuous increase in annual average temperature at a rate of 2 ° C/year for 2∼3 years. [ABSTRACT FROM AUTHOR]

In this paper, we generalize known results of nonabelian embedding tensor to the Hom setting. We introduce the concept of Hom-Leibniz-Lie algebra, which is the basic algebraic structure of nonabelian embedded tensors on Hom-Lie algebras and can also be regarded as a nonabelian generalization of Hom-Leibniz algebra. Moreover, we define a cohomology of nonabelian embedding tensors on Hom-Lie algebras with coeffcients in a suitable representation. The first cohomology group is used to describe infinitesimal deformations as an application. In addition, Nijenhuis elements are used to describe trivial infinitesimal deformations. [ABSTRACT FROM AUTHOR]

This paper proposes an algorithm for transmitting and reconstructing the estimated point cloud by temporally estimating a dynamic point cloud sequence. When a non-rigid 3D point cloud sequence (PCS) is input, the sequence is divided into groups of point cloud frames (PCFs), and a key PCF is selected. The 3D skeleton is predicted through 3D pose estimation, and the motion of the skeleton is estimated by analyzing the joints and bones of the 3D skeleton. For the deformation of the non-rigid human PC, the 3D PC model is transformed into a mesh model, and the key PCF is rigged using the 3D skeleton. After deforming the key PCF into the target PCF utilizing the motion vector of the estimated skeleton, the residual PC between the motion compensation PCF and the target PCF is generated. If there is a key PCF, the motion vector of the target PCF, and a residual PC, the target PCF can be reconstructed. Just as compression is performed using pixel correlation between frames in a 2D video, this paper compresses 3D PCFs by estimating the non-rigid 3D motion of a 3D object in a 3D PC. The proposed algorithm can be regarded as an extension of the 2D motion estimation of a rigid local region in a 2D plane to the 3D motion estimation of a non-rigid object (human) in 3D space. Experimental results show that the proposed method can successfully compress 3D PC sequences. If it is used together with a PC compression technique such as MPEG PCC (point cloud compression) in the future, a system with high compression efficiency may be configured. [ABSTRACT FROM AUTHOR]

The paper describes the application of the numerical tool quality index for an objective evaluation of complementary frequency response analysis (FRA) and vibroacoustic method (VM) test methods. These diagnostic methods are used in the industrial practice of transformer diagnostics for the assessment of the mechanical condition of windings and a core. The quality index is based on a numerical comparison of the curve obtained from measurements and the reference curve in a frequency domain. The quality index is based on estimators for the covariance, variance, and expected values. First, both methods of analysis were applied to a group of transformers of similar construction, leading conclusions on quality index values being quickly drawn. Next, it was applied to another transformer's FRA and VM measurement results. The results showed problems with its mechanical condition, thus confirming that the proposed methods can be used in the practical assessment of transformers with these two diagnostic methods. The assessment of transformer's active-part mechanical condition with complementary FRA and VM methods can be performed much more easily with the proposed quality indices. [ABSTRACT FROM AUTHOR]

Currently, highly contradictory knowledge characterises the thermally induced deformation of sands and the occurrence of the thermal collapse phenomenon: a volumetric contraction of such granular materials upon heating, which has been observed in some laboratory studies as opposed to a volumetric expansion. In this context, the effects of applied stress level and relative density, which seem to account for the inconclusive findings, remain disputed. A key challenge inherent to investigations of the thermally induced deformation of sands is the requirement for tremendous measurement accuracy (i.e. trueness and precision) and the ability to minimise measurement errors. This paper addresses this challenge and the conflicts presently characterising this subject by reporting a laboratory experimental campaign that accurately and repeatedly measures the thermally induced deformation of sand for different relative densities, stress levels and particle shapes by means of temperature-controlled oedometer tests. The results of this study show a monotonic volumetric expansion of sand upon heating and contraction upon cooling, with an irreversible contractive deformation remaining after one heating–cooling cycle. Specifically, irrespective of the stress level, relative density or particle shape, no thermal collapse is observed, challenging the actual occurrence of such a phenomenon in sands. [ABSTRACT FROM AUTHOR]