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1
Piras, Paolo, Valerio Varano, Maxime Louis, Antonio Profico, Stanley Durrleman, Benjamin Charlier, Franco Milicchio, and Luciano Teresi. "Transporting Deformations of Face Emotions in the Shape Spaces: A Comparison of Different Approaches." Journal of Mathematical Imaging and Vision 63, no. 7 (May 18, 2021): 875–93. http://dx.doi.org/10.1007/s10851-021-01030-6.
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AbstractStudying the changes of shape is a common concern in many scientific fields. We address here two problems: (1) quantifying the deformation between two given shapes and (2) transporting this deformation to morph a third shape. These operations can be done with or without point correspondence, depending on the availability of a surface matching algorithm, and on the type of mathematical procedure adopted. In computer vision, the re-targeting of emotions mapped on faces is a common application. We contrast here four different methods used for transporting the deformation toward a target once it was estimated upon the matching of two shapes. These methods come from very different fields such as computational anatomy, computer vision and biology. We used the large diffeomorphic deformation metric mapping and thin plate spline, in order to estimate deformations in a deformational trajectory of a human face experiencing different emotions. Then we use naive transport (NT), linear shift (LS), direct transport (DT) and fanning scheme (FS) to transport the estimated deformations toward four alien faces constituted by 240 homologous points and identifying a triangulation structure of 416 triangles. We used both local and global criteria for evaluating the performance of the 4 methods, e.g., the maintenance of the original deformation. We found DT, LS and FS very effective in recovering the original deformation while NT fails under several aspects in transporting the shape change. As the best method may differ depending on the application, we recommend carefully testing different methods in order to choose the best one for any specific application.
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Chu, Bin-Lin, Yeun-Wen Jou, and Meng-Chia Weng. "A constitutive model for gravelly soils considering shear-induced volumetric deformation." Canadian Geotechnical Journal 47, no. 6 (June 2010): 662–73. http://dx.doi.org/10.1139/t09-135.
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This study elucidates the deformational behavior of gravelly soils by analyzing how hydrostatic pressure and pure shearing affect deformational behavior. A series of drained, triaxial compression tests have been performed using large specimens made of gravelly soils, where the grain-size distribution curve was based on the field condition. The volumetric and shear deformations of gravelly soils have been determined by performing experiments with controlled stress paths — hydrostatic pressure was applied first followed by pure shearing. A simple and innovative constitutive model is also proposed. The proposed model is characterized by the following features of gravelly soils: (i) significant shear-induced volumetric deformation prior to failure, (ii) modulus stiffening under hydrostatic loading and degradation under shearing, and (iii) stress-induced anisotropy. In the proposed model, deformational moduli K and G vary according to the stress state. The stiffening and degradation of these moduli result in diverse deformational behavior of gravelly soils. In addition, an anisotropic factor, β, is introduced to represent stress-induced anisotropy. Moreover, the proposed model only requires eight material parameters; each of which can be obtained easily from experiments.
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VON GOSEN, W. "Stages of Late Palaeozoic deformation and intrusive activity in the western part of the North Patagonian Massif (southern Argentina) and their geotectonic implications." Geological Magazine 146, no. 1 (July 30, 2008): 48–71. http://dx.doi.org/10.1017/s0016756808005311.
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AbstractAnalyses of structures in the western part of the North Patagonian Massif (southern Argentina) suggest a polyphase evolution, accompanied by continuous intrusive activity. The first two deformations (D1, D2) and metamorphism affected the upper Palaeozoic, partly possibly older Cushamen Formation clastic succession and different intrusive rocks. A second group of intrusions, emplaced after the second deformational episode (D2), in many places contain angular xenoliths of the foliated country rocks, indicating high intrusive levels with brittle fracturing of the crust. Deformation of these magmatic rocks presumably began during (the final stage of) cooling and continued under solid-state conditions. It probably coincided with the third deformational event (D3) in the country rocks. Based on published U–Pb zircon ages of deformed granitoids, the D2-deformation and younger event along with the regional metamorphism are likely to be Permian in age. An onset of the deformational and magmatic history during Carboniferous times, however, cannot be excluded. The estimated ~W–E to NE–SW compression during the D2-deformation, also affecting the first group of intrusive rocks, can be related to subduction beneath the western Patagonia margin or an advanced stage of collisional tectonics within extra-Andean Patagonia. The younger ~N–S to NE–SW compression might have been an effect of oblique subduction in the west and/or continuing collision-related deformation. As a cause for its deviating orientation, younger block rotations during strike-slip faulting cannot be excluded. The previous D2-event presumably also had an effect on compression at the northern Patagonia margin that was interpreted as result of Patagonia's late Palaeozoic collision with the southwestern Gondwana margin. With the recently proposed Carboniferous subduction and collision south of the North Patagonian Massif, the entire scenario might suggest that Patagonia consists of two different pieces that were amalgamated with southwestern Gondwana during Late Palaeozoic times.
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Barkov, L. A., Marina N. Samodurova, and O. A. Nevraeva. "Kinematic and Dynamic Conditions in Metal Rolling of Porous Materials." Materials Science Forum 989 (May 2020): 705–10. http://dx.doi.org/10.4028/www.scientific.net/msf.989.705.
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Mathematical modeling of plastic deformations in rolling consists in a consequent combination of the general energetic relationship in plasticity and the variation inequality expressed the principle of minimum of entire deformation energy. A real deformation state in a plastic zone beneath rolls and corresponding kinematic and dynamics conditions on the contact surface are considered as a limited one for the consequent approximate deformation states and are found out by the method of approximated approach. Any realization of this method on personal computers requires a rational construction of a kinematic-possible velocity field in the spatial domain on plastic flow. Using the ordinary propositions and a new assumptions the authors have constructed a simple kinematic-possible velocity field in the plastic zone beneath rolls. On the base of the consequent approach in which the general energetic relationship and the variation inequality are interrelated the authors have been able to find out the geometric, kinematic and dynamics characteristics of plastic deformation’s states in metal rolling.
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Aleksandrov, A. S., T. V. Semenova, and N. P. Aleksandrova. "MATERIALS USED IN THE ROAD BASES: METHOD OF THE RESIDUAL DEFORMATIONS’ CALCULATION." Russian Automobile and Highway Industry Journal 16, no. 4 (September 8, 2019): 456–71. http://dx.doi.org/10.26518/2071-7296-2019-4-456-471.
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Materials and methods. The authors performed the analysis of the models for calculating residual deformations accumulated by granular materials and under the influence of repeated loads. The research showed the hereditary nature of the strain granular materials’ accumulation. Therefore, the authors used integral calculus for analytical solution of the residual deformation’s dependence on the number of repeated loads and on the magnitude of the main stresses. Moreover, the authors obtained the solution in the form of logarithmic and power functions, which associated the accumulated deformation with the deformation arising from the first load application. In determining the deformation from the first load application, the authors took into account the model of the theory of plasticity, in which the elastoplastic deformation was determined by the sum of two components elastic and plastic, as well as rheological models considering the deformation as the sum of three or four components. Generalizing the model for various materials, the authors gave the preference to the model, in which the elastoplastic deformation was determined by four components: instantaneous elastic and residual deformations, elastic (elastic-viscous) deformation and a viscoplastic component. Therefore, the residual strain from the first load application was represented by the sum of the two components, instantaneous irreversible and viscoplastic. The viscoplastic component of the deformation was a result of stress relaxation in a relatively short period of time equal to the duration of the load impact. Such research allowed taking into account the effect of speed on the duration of the load and the magnitude of the viscoplastic component of the residual deformation. The authors emphasized that taking into account the viscous-plastic component of residual deformation was most appropriate when calculating residual deformations of soils and materials treated with an organic binder. Granular materials were less sensitive to viscoplastic deformation under a single load application, but, when the voltage exceeded the elastic limit, and the more plastic adaptability of crushed stone, gravel, etc. viscoplastic deformation made a significant contribution to the accumulated residual deformation.Results. As a result, the authors carried out the analysis of experimental data on the triaxial compression of various granular materials and determined the parameters obtained for the power and logarithmic functions. The authors studied such materials as granite, gneissic, granodiorite and diorite crushed stone, sand, gravel and crushed stone, gravel mixtures with a mineral part from various rocks and fortified sands.Discussion and conclusions. The paper demonstrates the possibility of using the solutions for calculation of the surface displacement of the pavement layers of granular materials. The authors formulate the tasks for further research.
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Wiśniewski, Zbigniew, and Waldemar Kamiński. "Estimation and Prediction of Vertical Deformations of Random Surfaces, Applying the Total Least Squares Collocation Method." Sensors 20, no. 14 (July 14, 2020): 3913. http://dx.doi.org/10.3390/s20143913.
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This paper proposes a method for determining the vertical deformations treated as random fields. It is assumed that the monitored surfaces are subject not only to deterministic deformations, but also to random fluctuations. Furthermore, the existence of random noise coming from surface’s vibrations is also assumed. Such noise disturbs the deformation’s functional models. Surface monitoring with the use of the geodetic levelling network of a free control network class is carried out. Assuming that, in some cases, the control networks are insufficient in surface’s deformation analysis, additional and non–measurable reference points have been provided. The prediction of these points’ displacements and estimation of the free control network points’ displacement are carried out using the collocation method applying the total least squares adjustment. The proposed theoretical solutions were verified by the simulation methods and on the example of a real control network.
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Lazarus, Francis, Sabine Coquillart, and Pierre Jancène. "Axial deformations: an intuitive deformation technique." Computer-Aided Design 26, no. 8 (August 1994): 607–13. http://dx.doi.org/10.1016/0010-4485(94)90103-1.
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Коновалова and Valyeriya Konovalova. "Causes of Occurence and the Consequences of the Professional Deformations." Management of the Personnel and Intellectual Resources in Russia 5, no. 1 (February 17, 2016): 6–10. http://dx.doi.org/10.12737/18374.
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The article considers the essence and the reasons for the formation of professional deformation in various fields of activities, identifies the levels of their
manifestations, including: general professional deformations, special professional deformations, professional typological deformations, individualized deformations.
The main implications of professional deformation, seriously affecting the professional development and effectiveness are analized, including: disintegration of
professional development, distorted development professional, low professional mobility, increased deformation of the personality, etc. Psychological determinants
of the personality, contributing to the professional deformation are allocated. Special attention is paid to the peculiarities of professional deformation of leaders:
distinguished features, including gender, professional deformation managers; the factors that determine the risk of burnout of managers as a non-specific
professional deformation are summarized, including basic personality traits, models of overcoming behavior in difficult or critical situations, the style of behavior
in conflict situations, managerial skills.
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Erdélyi, Ján, Alojz Kopáčik, Ľubica Ilkovičová, Imrich Lipták, and Pavol Kajánek. "Monitoring of a concrete roof using terrestrial laser scanning." Geoinformatics FCE CTU 13 (December 21, 2014): 25–30. http://dx.doi.org/10.14311/gi.13.3.
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The paper deals with the geodetic monitoring of a parabolic shaped reinforced con-crete roof structure in the chemical company Duslo, Ltd. in Šaľa (Slovak Republic).The monitored structure is a part of the roof of a warehouse used for the storage offertilizer. The atmospheric conditions and the operation load caused deformationof the construction. For measurement was used the technology of terrestrial laserscanning. The displacements of the observed parts of the construction were cal-culated using planar surfaces by the procedure of Singular Value Decomposition ofmatrixes. The procedure of initial and 2 epochal measurements of deformations,the procedure of the data processing, and the results of the deformation monitoringare described.
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Fan, Jinyan, Zhibiao Guo, Xiaobing Qiao, Zhigang Tao, Fengnian Wang, and Chunshun Zhang. "Constant Resistance and Yielding Support Technology for Large Deformations of Surrounding Rocks in the Minxian Tunnel." Advances in Civil Engineering 2020 (September 28, 2020): 1–13. http://dx.doi.org/10.1155/2020/8850686.
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During the excavation of the Minxian tunnel, problems of large deformations of surrounding rocks and failure of support structures appeared frequently, which caused serious influences on construction safety and costs of the tunnel. Based on laboratory analysis of mineral composition and field investigations on deformation characteristics of the surrounding rocks, the large deformation mechanism of surrounding rocks of the tunnel was considered as water-absorbing swelling molecules of carbonaceous slate and stress-induced asymmetric structural deformations of the surrounding rocks. The structural deformations of surrounding rocks mainly include bending deformation, interlayer sliding, and crushing failure of local rock blocks. Then, a new constant resistance and yielding support technology based on the constant resistance and large deformation (CRLD) anchor cable was proposed to control large deformations of surrounding rocks. The field tests and deformation monitoring were carried out. The monitoring results showed that compared with original support measure, the surrounding rock deformations, stresses of primary supports, and permanent lining using new support technology decreased greatly. Among them, the maximum deformation of surrounding rock was only 73 mm. The effects of field application and results of deformation monitoring showed that the new support technology can effectively control large deformations of the surrounding rocks in the Minxian tunnel.
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Lin, P. P., M. D. Chawla, and P. M. Wagner. "Three-Dimensional Deformation Comparison Between F-16 Bias and Radial Aircraft Tires." Tire Science and Technology 25, no. 1 (January 1, 1997): 63–75. http://dx.doi.org/10.2346/1.2137532.
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Abstract This paper presents an optical technique called fringe projection to measure 3D tire deformation subjected to different loads, percentages of deflection, and yaw angles. Unlike the well-known Moiré method, the proposed technique uses a single light source and one grating, thus requiring no image superposition. As a result, the measurement is not as sensitive to vibration as the Moiré method. The fringe projection also differs from the commonly used optical inspection technique in manufacturing industry via line scanning known as structured light, which cannot be applied to dynamic deformation measurements. The recently developed subpixel resolution was employed to accurately locate the optical fringe centers, which in turn improves the accuracy in 3D geometry determination. A fiber-optic displacement sensor was also placed close to the tire sidewall to measure the deformational change of the selected reference point. Finally, the deformations are compared between F-16 bias and radial aircraft tires when subjected to the same loading conditions.
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Carter, Karen E. "Grenville orogenic affinities in the Red Mountain area, Llano Uplift, Texas." Canadian Journal of Earth Sciences 26, no. 6 (June 1, 1989): 1124–35. http://dx.doi.org/10.1139/e89-096.
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The Red Mountain area in the southeast corner of the Llano Uplift contains evidence of a Grenville-age, polyphase, non-coaxial deformational history. Four synmetamorphic deformational phases affected the Precambrian Click Formation of the Packsaddle Group, and a single shear-related deformation is observed in the Big Branch and Red Mountain gneisses. The first phase of deformation produced tight folds with an axial–planar metamorphic foliation. The second, and most intense, pervasive deformational phase produced the regional metamorphic layering, isoclinal folds, transposition of bedding, and mylonitic textures in the gneisses. The third deformation is characterized by tight to isoclinal, north-verging folds with an axial–planar differentiation crenulation cleavage. The fourth phase of deformation resulted in a north-northwest-trending differentiation crenulation cleavage that is axial–planar to small east-northeast-verging folds. The growth of cordierite over all foliations indicates that low-pressure metamorphism postdated all four deformational phases.The second deformation had begun at the latest by 1167 ± 2 Ma, the age of metamorphism of the gneisses, and before the intrusion of melarhyolite dikes dated at 1080 ± 30 Ma. Thus, the orogenic event(s) responsible for the complex deformational and metamorphic history is Grenvillian in age.
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Briais, J., F. Guillocheau, E. Lasseur, C. Robin, J. J. Châteauneuf, and O. Serrano. "Response of a low-subsiding intracratonic basin to long wavelength deformations: the Palaeocene–early Eocene period in the Paris Basin." Solid Earth 7, no. 1 (February 8, 2016): 205–28. http://dx.doi.org/10.5194/se-7-205-2016.
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Abstract. The uppermost Cretaceous to early Palaeogene is a period of major deformations of the western part of the Eurasian plate with prominent basin inversions starting from the Coniacian onwards. These deformations occur in a complex geodynamic setting within both the context of the Africa–Eurasia convergence and the North Atlantic opening. While Mesozoic graben inversions have been extensively studied, particularly in Eastern Europe and the North Sea, more gentle deformations that affect thicker crust areas (intracratonic basins and emerged lands) are not as well documented. The objective of this study is to constrain the exact timing, type, and magnitude of the early Palaeogene deformations affecting the intracratonic Paris Basin and to integrate them at the western European scale. Low-amplitude deformations are attempted through a high-resolution reconstitution of its stratigraphic record based on well-dated outcrops and well-dated wells, and a high number of well-logs that are correlated using the “stacking pattern” sequence stratigraphic technique. Two orders of sequences are identified (third and fourth order) and correlated throughout the basin. Basin geometric and palaeogeographic reconstitutions are based on sediment thickness and facies analysis. Two-dimensional accommodation space measurements were taken in order to quantify the magnitude of the deformations. Three phases of deformation were recognized. 1. An intra-Maastrichtian–pre-Thanetian (59 Ma) deformation, with major uplift and erosion of the Cretaceous strata with two sub-periods of deformation: Maastrichtian–pre-middle-Danian and Upper Danian–pre-Thanetian long-wavelength deformations. This period of major deformation is coeval with Upper Cretaceous/pre-Danian compressive deformations linked to the Africa–Eurasia convergence in southern France and with volcanic activity from the North Atlantic to Massif Central and the Rhenish Shield during the Palaeocene. 2. An early Ypresian (55.1–54.3 Ma) medium-wavelength deformation ( × 10 km), here reported to be a stress rearrangement related to the onset of the North Atlantic opening. 3. An uppermost Ypresian (49.8 Ma) long-wavelength deformation ( × 100 km), contemporaneous with flexural compressive deformations in the Aquitaine Basin (Pyrenean deformation), and related to the Iberia–Eurasia convergence.
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Briais, J., F. Guillocheau, E. Lasseur, C. Robin, J. J. Châteauneuf, and O. Serrano. "Response of a low subsiding intracratonic basin to long wavelength deformations: the Palaeocene–early Eocene period in the Paris basin." Solid Earth Discussions 7, no. 4 (December 7, 2015): 3587–643. http://dx.doi.org/10.5194/sed-7-3587-2015.
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Abstract. The uppermost Cretaceous to early Palaeogene is a period of major deformations of the western part of the Eurasian plate with prominent basin inversions starting from the Coniacian onwards. These deformations occur in a complex geodynamic setting within both the context of the Africa–Eurasia convergence and the North Atlantic opening. While Mesozoic graben inversions have been extensively studied, particularly in Eastern Europe and the North Sea, more gentle deformations that affect thicker crust areas (intracratonic basins and emerged lands) are not as well documented. The objective of this study is to constrain the exact timing, type and magnitude of the early Palaeogene deformations affecting the intracratonic Paris basin and to integrate them at the Western European scale. Relatively gentle deformations are attempted through a high-resolution reconstitution of its stratigraphic record based on outcrops and well-dated wells, and a high number of well-logs that are correlated using the "stacking pattern" sequence stratigraphic technique. Two orders of sequences are identified (third- and fourth-order) and correlated throughout the basin. Basin geometric and palaeogeographic reconstitutions are based on sediment thickness and facies analysis. Two-dimensional accommodation space measurements were taken in order to quantify the magnitude of the deformations. Three phases of deformation were recognized. 1. An intra-Maastrichtian–pre-Thanetian (59 Ma) deformation, with major uplift and erosion of the Cretaceous strata with two sub-periods of deformation: Maastrichtian–pre-middle-Danian and Upper Danian–pre-Thanetian long wavelength deformations. This period of major deformation is coeval with Upper Cretaceous–pre-Danian compressive deformations linked to the Africa–Eurasia convergence in southern France and with volcanic activity from the North Atlantic to Massif Central and the Rhenish Shield during the Palaeocene; 2. an early Ypresian (55.1–54.3 Ma) medium wavelength deformation (× 10 km), here reported to be a stress rearrangement related to the onset of the North Atlantic opening; 3. an uppermost Ypresian (49.8 Ma) long wavelength deformation (× 100 km), contemporaneous with flexural compressive deformations in the Aquitaine Basin (Pyrenean deformation), and related to the Iberia–Eurasia convergence.
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Bakushev, S. V. "DIFFERENTIAL EQUATIONS OF EQUILIBRIUM OF ELASTIC PERFECTLY PLASTIC CONTINUOUS MEDIUM FOR PLANE DEFORMATION IN CYLINDRICAL COORDINATES AT BILINEAR APPROXIMATION OF THE CLOSING EQUATIONS." STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS, no. 1 (February 25, 2021): 18–33. http://dx.doi.org/10.37538/0039-2383.2021.1.18.33.
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Abstract. The article considers the construction of differential equations of equilibrium in displacements for plane deformation of elastic perfectly plastic regarding shear deformations continuous medium and nonlinearly elastic continuous medium with respect to volumetric deformations with bilinear approximation of the closing equations, both regarding and regardless geometrical nonlinearity in a cylindrical coordinate system. Nonlinear diagrams of volumetric and shear deformation are approximated by bilinear functions. Proceeding from the assumption of independence, generally speaking, of volume and shear deformation from each other, five main cases of physical dependencies are considered, depending on the relative position of the break points of bilinear diagrams of volume and shear deformation. The construction of bilinear physical dependencies is based on the calculation of the secant moduli of volumetric and shear deformation. In this case, in the first section of the diagrams, the secant modulus of both volumetric and shear deformation is constant, while in the second section of the diagrams, the secant modulus of volumetric deformation is a function of volumetric deformation, and the secant shear modulus is a function of the intensity of shear deformations. Substituting the corresponding bilinear physical relations into the differential equations of equilibrium of a continuous medium, written both regardless and regarding geometrical nonlinearity, the resolving differential equations of equilibrium in displacements for plane deformation in a cylindrical coordinate system are received. The received differential equations of equilibrium in displacements in cylindrical coordinates can be applied in determining the stress-strain state of elastic perfectly plastic with respect to shear deformations continuous medium and nonlinearly elastic with respect to volumetric deformations continuous medium under conditions of plane deformation, both regarding and regardless geometrical nonlinearity, physical relations for which are approximated by bilinear functions.
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Omar, Mohd Nadzeri, and Yongmin Zhong. "Flexible Mass Spring Method for Modelling Soft Tissue Deformation." International Journal of Engineering Technology and Sciences 7, no. 2 (July 3, 2021): 24–41. http://dx.doi.org/10.15282/ijets.7.2.2020.1003.
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It is well accepted that soft tissue deformation is a combination of linear and nonlinear response. During small displacements, soft tissues deform linearly while during large displacements, soft tissues show nonlinear deformation. This paper presents a new approach for modelling of soft tissue deformation, from the standpoint of Mass Spring Method (MSM). The proposed MSM model is developed using conical spring methodology which allow the MSM model to have different stiffnesses at different displacements during deformation. The stiffness variation creates flexibility in the model to simulate any linear and nonlinear deformations. Experimental results demonstrate that the deformations by the proposed method are in good agreement with those real and phantom soft tissue deformations. Isotropic and anisotropic deformations can be accommodated by the proposed methodology via conical spring geometry and configuration of the springs. The proposed model also able to simulate typical viscoelastic behaviour of soft tissue.
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Fialowski, Alice, Ashis Mandal, and Goutam Mukherjee. "Versal Deformations of Leibniz Algebras." Journal of K-Theory 3, no. 2 (June 3, 2008): 327–58. http://dx.doi.org/10.1017/is008004027jkt049.
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AbstractIn this work we consider deformations of Leibniz algebras over a field of characteristic zero. The main problem in deformation theory is to describe all non-equivalent deformations of a given object. We give a method to solve this problem completely, namely work out a construction of a versal deformation for a given Leibniz algebra, which induces all non-equivalent deformations and is unique on the infinitesimal level.
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Barchukova, Tetіana. "Work piles - columns with soil under constant influence of vertical and cyclically approximated horizontal loads." ACADEMIC JOURNAL Series: Industrial Machine Building, Civil Engineering 2, no. 51 (October 12, 2018): 19–23. http://dx.doi.org/10.26906/znp.2018.51.1283.
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The article describes an experimental study aimed at identifying common patterns of joint work of piles - columns with soil with vertical and cyclically applied horizontal loads. The study examines the deformation processes occurring in the soil. At any pressure value, soil deformations can be divided into two groups, which are restored (elastic) and residual. When the pressure is less than the structural strength, elastic deformations appear. With a pressure of greater structural strength, elastic and residual deformations appear. Elastic deformations appear throughout the depth, residual deformations develop in the depth of the deformation zone, where the stress exceeds the structural strength of the soil. After removing the load, the elastic deformation disappears, and the residual remains. The lower limit of the residual strain zone is at a depth, where the stresses from the load transmitted by the column of piles below its base are balanced by the structural strength of the soil.
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Liu, Jing, Zhifeng Shi, Yimin Shao, and Huifang Xiao. "Effects of spall edge profiles on the edge plastic deformation for a roller bearing." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 233, no. 5 (May 15, 2017): 850–61. http://dx.doi.org/10.1177/1464420717710276.
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A clear understanding of the plastic deformations at the spall edges is a primary task for the edge propagation predictions in rolling element bearings. This work proposed an elastic–plastic two-dimensional finite element model for calculating the contact stress and plastic deformation between the rolling element and raceway. This model includes a rolling element and one raceway. The rectangular plane strain solid elements are used to formulate the finite element model. The Coulomb model is used to formulate the friction force between the rolling element and raceway. A bilinear kinematic hardening material model is used in the finite element model, which can formulate the elastic–plastic deformations. The studied spall edge profiles are assumed to be sharp and cylindrical ones. To validate the finite element model, the contact deformations between the rolling element and the raceway from the proposed model and Hertzian contact theory are compared. Effects of spall edge profiles on the edge plastic deformations at the edge are analyzed, as well as the edge plastic deformation zone width. Based on the numerical results, the relationship between the edge plastic deformation and the spall edge profile, and that between the edge plastic deformation zone width and the spall edge profile are established. The results show that the edge plastic deformation is significantly influenced by the spall edge profiles, as well as the edge plastic deformation zone width. This paper provides a clear understanding of the effects of the edge profiles on the plastic deformations and propagation at the spall edge.
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Kim, Jae Hyun, Bong Kyun Jang, Kyung Shik Kim, Jung Yup Kim, Byung Ik Choi, Sang Hyun Jun, and Jun Ho Kim. "An Analysis of Non-Uniform Deformation of a Pantograph for Bellows Applications." Key Engineering Materials 452-453 (November 2010): 585–88. http://dx.doi.org/10.4028/www.scientific.net/kem.452-453.585.
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In this study, an analytical model is developed to analyze non-uniform deformation of a pantograph. The analytical model is verified by comparing predicted deformations with experimentally measured deformations of a pantograph. The effects of total displacement and gaps on non-uniformity are numerically simulated to provide the physical insight into the deformation mechanism of a pantograph. Design guidelines are suggested to minimize non-uniform deformation of a pantograph, and hence also of an associated bellows.
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Zakhmatova, T. V., V. V. Shchedrenok, and O. V. Moguchaya. "ORTHOSTATIC TORTUOSITIS TRANSFORMATION OF THE NECK’S MAIN ARTERIES." HERALD of North-Western State Medical University named after I.I. Mechnikov 7, no. 2 (June 15, 2015): 45–51. http://dx.doi.org/10.17816/mechnikov20157245-51.
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Among 350 surveyed deformations of internal carotid arteries revealed in 38.6% of cases. At pathological deformation observed acceleration of flow speed indicators from 55% to 65% in part of tortuosity, average value of systolic speeds of a blood flow was 166±28.3 cm/s at the left and 174±30.2 cm/s at the right side. In vertical position in 31.6% of cases at pathological deformation observed transfor mation of tortuosity form. deformation corners became blunt, the gradient of flow speed indicators decreased or was absent, in some cases course of internal carotid arteries became rectilinear. Artificial deformations of vertebral arteries course revealed in 79.4% of people, average value of systolic speed of a blood flow was 92±15.3 cm/s at the left and 76±12.5 cm/s at the right side. In vertical position in deformations of the vertebral arteries, which carried to pathological, in 28.8% of cases a form of deformation was transformed to unpathological tortuosity. duplex sonography in vertical position in patients with tortuosity discovered new approaches in diagnostics of pathological deformations and defines indications to operative treatment.
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Ustinov, Artem M., Anatoliy A. Klopotov, A. I. Potekaev, S. B. Galsanov, Yu A. Abzaev, O. G. Volokitin, and Yu A. Vlasov. "Study of the Elasto-Plastic Deformation of the Steel/Steel Adhesive Joint Using Digital Image Correlation Method." Solid State Phenomena 303 (May 2020): 143–60. http://dx.doi.org/10.4028/www.scientific.net/ssp.303.143.
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The study of the steel/steel adhesive joint using digital image correlation method has been carried out. A correlation between the evolution of distributions of deformation regions on the surface of the adhesive joint and the stages on the deformation curve is revealed. It has been found that a destruction along the adhesive seam begins when the adhesive joint reaches total deformations of about 0.5%. The analysis of deformation fields on the steel surface have allowed revealing the formation of extensive tension regions with greatest deformations at the interface of loaded plates. An increase in the values of compression deformations at the ends of the patch and a significant increase in the areas of these regions have been revealed.
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Tang, Ai Jun, Hai Long Ma, and Zhan Qiang Liu. "Elastic-Plastic Deformation of Milling Thin Wall Part." Applied Mechanics and Materials 345 (August 2013): 321–24. http://dx.doi.org/10.4028/www.scientific.net/amm.345.321.
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Aircraft components are mostly made by aluminum alloy as thin wall types. These parts are usually end milled to required thicknesses and tight tolerances in specific areas. The thin wall parts are difficult to machine because they are easy to vibrate and deformed due to their lower rigidity. This paper proposes a new elastic-plastic deformation model which is suitable for prediction of machining deformations of end milled thin wall parts. The theoretical deformation model is established on the basis of the equations of Von Kármán. The part deformations are simulated using FE analysis and Matlab. The results show that the deformations for the end milling of thin wall parts can be captured with very high accuracy using the proposed elastic-plastic deformation prediction model.
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Speich, Marco, Wolfgang Rimkus, Markus Merkel, and Andreas Öchsner. "Large Deformation of Metallic Hollow Spheres." Materials Science Forum 623 (May 2009): 105–17. http://dx.doi.org/10.4028/www.scientific.net/msf.623.105.
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Hollow sphere structures are a new group of advanced lightweight materials for multifunctional applications. Within the scope of this paper, the uniaxial deformation behaviour in the regime of large deformations is investigated. Appropriate computational models are developed to account for the deformation mechanisms occurring under high deformations. Macroscopic stress-strain curves are derived and the influence of different material parameters is investigated.
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Fares, N. "Effective Mechanical Properties of Composites at Finite Deformations." Journal of Applied Mechanics 60, no. 1 (March 1, 1993): 8–14. http://dx.doi.org/10.1115/1.2900784.
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A new representation theorem for the deformation gradient rate in the presence of cracks and kinematic constraints is presented. This representation theorem uses an extension of the concept of transformation strains to finite deformations. Based on the representation theorem the overall concentration factor was decomposed into contributions from the opening and sliding of cracks and from material nonhomogeneities. Also, inelastic deformations at the microscale were related to those at the macroscale through elastic concentration factors, where it was found that some of the elastic deformation at the microscale may contribute to the macroscale inelastic deformations.
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Dudarev, Evgenii, Galina Bakach, Aleksandr I. Potekaev, Yurii Kolobov, Oleg Kashin, and Mickle Zhorovkov. "Influence of Interstitial Impurities on Deformational Behavior and Fracture Mechanism of Submicrocrystalline Titanium at Room and Elevated Temperatures." Advanced Materials Research 1013 (October 2014): 138–45. http://dx.doi.org/10.4028/www.scientific.net/amr.1013.138.
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General trends and other aspects of the deformational behavior, localization of plastic deformation on the macroscale level, and fracture of submicrocrystalline and coarse-grained titanium with different interstitial impurity levels are established. It is shown that for the submicrocrystalline structure as well as for the coarse-grained structure, strengthening by interstitial impurities decreases with increase of the deformation temperature. Experimental data are presented which indicate that in the development of grain-boundary sliding in submicrocrystalline titanium with simultaneous onset of recrystallization, a high degree of plastic deformation is reached before fracture occurs, where the deformational behavior and localization of plastic deformation on the macroscale level are analogous to the same processes under superplastic flow.
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Camiré, G. "Development of inverted metamorphic gradient in the internal domain of the Taconian belt, Gaspé Peninsula." Canadian Journal of Earth Sciences 32, no. 1 (January 1, 1995): 37–51. http://dx.doi.org/10.1139/e95-005.
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The Mont Logan Nappe is part of the Taconian internal domain of the Quebec Appalachians, and is entirely made up of synrift to passive margin elastics and volcanics of the Shickshock Group. Rocks of the Mont Logan Nappe were affected by both Taconian and Acadian deformations but regional prograde metamorphism is Taconian and limited to the D1 deformational event. Thermobarometry and mineral assemblages indicate that the metasedimentary and metavolcanic rocks of the Mont Logan Nappe have recorded peak temperatures in the range 610–700 °C under pressures of approximately 600–700 MPa, and that prograde metamorphism was accompanied by the development of an inverted metamorphic gradient of −40 to −75 °C/km. The preferred interpretation of the cause of the inverted gradient is dissipative heating accompanying deformation along an intracontinental synmetamorphic thrust fault located at the top of the inverted metamorphic sequence.
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Ji, Wei, Guo Hua Qin, and Hai Chao Ye. "An Advanced FEA Based Analytical Strategy for the Milling of Overall Thin-Walled Workpieces." Advanced Materials Research 308-310 (August 2011): 499–502. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.499.
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A multi-level finite element analysis approach is introduced to investigate force-induced deformations in milling of overall thin-walled structures. This prediction algorithm takes into account the deformation of the workpiece in different points of the tool path. The machining conditions are modified at each analysis step when the cutting force and deformation achieve a local equilibrium. The effects of feed rates on the workpiece form deformation can be predicted using a theoretical workpiece model. In addition, this methodology can be used to compensate the machining error taking into account the predicted workpiece deformations.
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Plavšić, M. B., Iva Pajić-Lijaković, and N. L. Lazić. "Scaling of Network Segment Dimensions in Hyperelastic Composites." Materials Science Forum 494 (September 2005): 463–68. http://dx.doi.org/10.4028/www.scientific.net/msf.494.463.
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The change in elastomer tensile moduli, as formulated in the Gaussian statistical theory of rubber elasticity, with deformation, is considered both experimentally and theoretically. Gum elastomers of different structures and corresponding materials filled with carbon black, as reinforcing filler, are investigated experimentally. For all materials considered, the same scaling pattern with negative and low slope for small deformations, and positive and higher slope for large deformations is obtained, indicating two distinct mechanisms of elastic response. Most pronounced is the similarity of small deformation responses for filled materials. Considering the modulus as an elastic energy density gradient dependent on structure changes with deformation, and interpreting the changes for small deformations in terms of conformational energy change, the fractal dimension of a new type is formulated. It describes the decrease in elastomer network connectivity with deformations, which is discussed in terms of conformon dynamics. Possibilities of application of Faynman's path integral method and statistical method of random walk to the lattice are considered for the conformon, as well.
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Dragobetskii, Volodymyr, Mykhaylo Zagirnyak, Olena Naumova, Sergii Shlyk, and Aleksandr Shapoval. "Method of Determination of Technological Durabilityof Plastically Deformed Sheet Parts of Vehicles." International Journal of Engineering & Technology 7, no. 4.3 (September 15, 2018): 92. http://dx.doi.org/10.14419/ijet.v7i4.3.19558.
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The purpose of the article is to develop an apparatus providing maximum or predicted durability of parts treated during their manufacture by plastic deformation. In these terms, the parameters of the technological process should provide the maximum or expected increase of the endurance limit in comparison with the initial parts values before the strengthening by the surface plastic deformation or after plastic forming. The article describes the influence of the degree of preliminary deformation on the kinetics of fatigue failure of metals and alloys. Experimental data of the ultimate deformations of welded workpieces were obtained, which make it possible to evaluate the manufacturing of parts with a weld seam at the design stage of the technological process. The developed method made it possible to determine the nonstationary field of stresses in the deformation region, ultimate deformations and the most rational scheme of the stress-strain state, which excludes the localization of deformations and destruction of the weld zone of a welded cylindrical workpieces.
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Merzlikin, Artem, Oleksandr Yaytsov, Olga Pidgurnaya, and Victor Nazimko. "RESEARCH OF DEFORMATIONS AND OPTIMIZATION OF PARAMETERS OF DEGASATION WELLS." JOURNAL of Donetsk mining institute, no. 2 (2020): 49–57. http://dx.doi.org/10.31474/1999-981x-2020-2-49-57.
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Purpose. Investigation of deformation of the mouth of the degassing well depending on the deformation of the rocks around the preparatory work Methodology. The deformation of the mouth of the degassing well as a function of deformations of the roof rocks of the preparatory workings from which the well was drilled is considered. The dependence of the required depth of well sealing on the level of methane leakage and roof deformation is established. Results. It is experimentally proved that in the zone of active shifts behind the operating lava, where the main amount of explosive methane is released from the massif, the mouths of degassing wells change and the main types of irreversible deformations take place. With the distance from the contour of the preparatory production, the distance between adjacent concentrated deformations of the wellbore increases according to the logarithmic dependence, and these deformations are distributed according to the normal law. The average value of the concentrated deformation of the degassing well is in logarithmic dependence on the displacements on the contour of the preparatory work. The tensile deformation of the degassing well axis decreases with distance from the production contour into the array. Stratification of rocks leads to gas leakage and air suction, which reduces the efficiency of degassing. Permissible concentrated deformations of the degassing wellbore should not exceed its radius. Originality. The empirical power dependence of the required length of sealing of the degassing well on the allowable leaks and displacements of the roof of the preparatory workings from which the well was drilled is established. Practical value. Methods for calculating the required sealing depth of the degassing well have been developed and measures have been proposed to increase its stability, which increase the reliability of the degassing system as a whole and help increase the safety of underground coal mining.
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Nawab, Yasir, Frédéric Jaquemin, Pascal Casari, Nicolas Boyard, and Vincent Sobotka. "Evolution of chemical and thermal curvatures in thermoset-laminated composite plates during the fabrication process." Journal of Composite Materials 47, no. 3 (February 22, 2012): 327–39. http://dx.doi.org/10.1177/0021998312440130.
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Residual deformations and stresses formation in the thermoset-laminated composite is a frequently studied subject in the recent years. During fabrication, the laminated composites undergo chemical deformation during cross-linking and thermal deformation while cooling. In thin laminates, due to large displacements and complex evolution of shape, these deformations can only be explained by using nonlinear strain–displacement relationship. In the present article, we calculated together for the first time, the thermal and chemical deformations occurring in carbon/epoxy laminates by considering a nonlinear geometrical approach to understand the evolution of shape and hence residual stresses induced during fabrication process. The effect of fibre fraction on the chemical and thermal deformations is studied as well.
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Lăzureanu, Cristian. "Integrable Deformations of Three-Dimensional Chaotic Systems." International Journal of Bifurcation and Chaos 28, no. 05 (May 2018): 1850066. http://dx.doi.org/10.1142/s0218127418500669.
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The integrable deformation method for a three-dimensional Hamilton–Poisson system consists in alteration of its constants of motion in order to obtain a new Hamilton–Poisson system. We assume that a three-dimensional system of differential equations has a Hamilton–Poisson part and a nonconservative part. We give integrable deformations of the Hamilton–Poisson part and, adding the nonconservative part, we obtain integrable deformations of the considered three-dimensional system of differential equations. In particular, applying this method to chaotic systems may lead to new systems with chaotic behavior. We use this method to obtain integrable deformations of Lorenz, Chen, and Rössler systems. Using particular deformation functions, we have pointed out some deformations of the above-mentioned attractors.
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Strzałkowski, Piotr, and Katarzyna Szafulera. "Occurrence of Linear Discontinuous Deformations in Upper Silesia (Poland) in Conditions of Intensive Mining Extraction—Case Study." Energies 13, no. 8 (April 13, 2020): 1897. http://dx.doi.org/10.3390/en13081897.
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Currently, linear discontinuous deformations in mining areas are an important issue, both due to the frequency of their occurrence and the threat they pose to general safety. This paper presents a case study of an occurrence of such a deformation. The analyses of the geological and mining conditions, as well as the conducted calculations presented herein, indicate that the cause of the deformation was the occurrence of high-value horizontal tensile strains. It was triggered by mining exploitation carried out with caving in three seams at depths between 200 and 545 m. An additional factor conductive to the creation of the deformation was the tectonic structure of the rock mass. The subject matter of the paper is significant given the growing number of discontinuous linear deformations occurring on the surface due to underground mining—even if the mining was conducted at great depths. They were formed as a result of intensive underground mining operations and the occurrence of high-value deformations. These deformations were particularly dangerous to building structures on the surface, which were often damaged. For this reason, it was worthwhile to make arrangements regarding the correlation between the occurrence of the deformations and the values and the distribution of continuous deformations caused by underground extraction, as well as the existence of tectonic faults.
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Semyonov, Mikhail G., Svetlana S. Mushkovskaya, and Kseniya U. Kovalenko. "The valuation of the residual and secondary deformation of the medium face zone in patients with unilateral cleft lip." Pediatric Traumatology, Orthopaedics and Reconstructive Surgery 6, no. 3 (September 28, 2018): 56–62. http://dx.doi.org/10.17816/ptors6356-62.
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Background. The treatment of patients with cleft lip and palate is a complicated medical-social problem. The residual and secondary deformations of the nose, upper lip, and dentoalveolar require surgical correction in these patients after undergoing complete reconstruction as a child.
Aim. To systematize the degree of severity of the residual secondary deformation of the medium face zone in adult patients after previous surgery.
Materials and methods. This scientific work was based on the results of 42 adult patients with unilateral cleft lip after undergoing complete reconstructive surgery as a child. The valuation of residual and secondary deformations of the nose, upper lip, and vestibule was performed in adults aged 25–40 years. The typical residual deformation at these locations was determined and separated into three groups and given a value.
Results. We observed that 91% of the patients with unilateral cleft lip had a deformation in the medium face; of these patients, 15% had severe deformation with an absolute indication for surgery.
Conclusion. The residual and secondary deformations of the medium face zone were diagnosed in 91% (80.6%–96.7%) of the patients operated using the Miro-Limberg-Obuyhovoi method in the remote period. Moreover, 15% of these deformations had an absolute indication for surgery. The three numbers used in the valuation system of the residual and secondary deformations of the medium face zone in patients with a unilateral cleft lip enable impartial and quick determination of the intensity of one or more deformations of the nose, lip, or vestibule of the mouth.
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Bauchau, O. A., and S. Han. "Flexible joints in structural and multibody dynamics." Mechanical Sciences 4, no. 1 (February 13, 2013): 65–77. http://dx.doi.org/10.5194/ms-4-65-2013.
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Abstract. Flexible joints, sometimes called bushing elements or force elements, are found in all structural and multibody dynamics codes. In their simplest form, flexible joints simply consist of sets of three linear and three torsional springs placed between two nodes of the model. For infinitesimal deformations, the selection of the lumped spring constants is an easy task, which can be based on a numerical simulation of the joint or on experimental measurements. If the joint undergoes finite deformations, identification of its stiffness characteristics is not so simple, specially if the joint is itself a complex system. When finite deformations occur, the definition of deformation measures becomes a critical issue. This paper proposes a family of tensorial deformation measures suitable for elastic bodies of finite dimension. These families are generated by two parameters that can be used to modify the constitutive behavior of the joint, while maintaining the tensorial nature of the deformation measures. Numerical results demonstrate the objectivity of the deformations measures, a feature that is not shared by the deformations measures presently used in the literature. The impact of the choice of the two parameters on the constitutive behavior of the flexible joint is also investigated.
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Pan, Peng, Yu Zhang, Shi Yan Song, and Lie Ping Ye. "Factors Influencing Maximum and Residual Deformations of SDOF Systems Subjected to Large Ground Motions." Advanced Materials Research 243-249 (May 2011): 170–77. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.170.
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The maximum and residual deformations of structures subjected to strong ground motions are the most importance indexes, particularly under the performance-based design framework, thus understanding the influencing factors is of great importance to seismic design. In this study, single degree of freedom (SDOF) systems with varying structural properties are analyzed using a series of strong ground motions from FEM/SAC project. The influences of three structural parameters, i.e., yield force, second stiffness after yielding, and stiffness degradation, on the maximum and residual deformations are investigated based on the statistics of the analysis results. The analysis results suggest the follows: (1) larger yield forces lead to smaller residual and maximum deformations for short period structures, and they lead to smaller residual deformations but no necessarily smaller maximum deformation for intermediate and long period structures; (2) larger second stiffness lead to smaller residual and maximum deformations for short period structures, and they lead to smaller residual deformations but no necessarily smaller maximum deformation for intermediate and long period structures; (3) smaller stiffness degradation index leads to smaller maximum deformations but larger residual deformations.
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Murashkin, Evgenii V., and Marina V. Polonik. "Determination of a Loading Pressure in the Metal Forming by the Given Movements." Advanced Materials Research 842 (November 2013): 494–99. http://dx.doi.org/10.4028/www.scientific.net/amr.842.494.
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We propose a mathematical model of large elastocreep deformations. As part of the constructed mathematical model the problem of deformation of the material in the vicinity of microdefect was solved. Integro-differential dependence of external pressure from irreversible deformations and displacements was obtained. The laws of loading material from vector displacements were calculated. We have shown that the monotonous laws of deformation can lead to non-monotonous stress changes.
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Jian, LIU, WANG Jinning, and WANG Zhiyong. "Detecting the deformation of fast ice by InSAR technology with Sentinel-1A descending and ascending orbits data." E3S Web of Conferences 206 (2020): 03028. http://dx.doi.org/10.1051/e3sconf/202020603028.
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Accurate mapping of fast ice deformation can effectively characterize the rheological behavior of fast ice and subsequently improve sea ice model. This study used the Sentinel-1A descending and ascending orbits data to detect the deformations of fast ice in the Baltic Sea. A method for automatically obtaining fast ice edge line by combining interferometric coherence image and SAR amplitude image was proposed. Then, the deformations of fast ice were detected from different incidence angles with the descending and ascending orbits data. The results showed that the deformations in radar line of sight obtained from the descending and ascending orbits data were 38cm and 37cm respectively within the fast ice region of 960km2 in the study area. The continuous strong southwest wind was the principal reason for the deformation, and the deformation direction was dominated by east to west. Moreover, the inner fast ice kept stable and its deformation was smaller due to the protection of outer consolidated ice. The experimental results in this paper showed that the deformation trend and characteristics of fast ice can be better understood by InSAR technology with multi-orbits SAR data.
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Seo, Seung Il, and Jae Gyu Noh. "Development of a System for Prediction and Visualization of Welding Deformations of Stiffened Plates." Journal of Ship Production 19, no. 02 (May 1, 2003): 84–90. http://dx.doi.org/10.5957/jsp.2003.19.2.84.
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To prevent problems caused by welding deformation, preparation in the design stage is necessary. Countermeasures in the design stage are also the most cost-effective method. In this study, to give designers information on the welding deformations, a system to calculate and visualize the welding deformations is developed. The model to visualize the deformation is the stiffened plate common in the ship structure. To increase computational efficiency, theoretical solutions to calculate the deformations of plate and stiffener are used instead of numerical analysis. Also, to ensure accuracy, experiments to estimate bending moments causing the welding deformations are performed. A computer program written with Visual C++ is developed for interactive data input, calculation of welding deformations, and display of deformed shape. Designers can change the design in the early stage after checking the deformed shape with this system.
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Klochkov, Yuriy V., Anatoliy P. Nikolaev, Olga V. Vakhnina, and Mikhail Yu Klochkov. "Variants of determining correlations of deformation theory of plasticity in the calculation of shell of rotation on the basis of finite element method." Structural Mechanics of Engineering Constructions and Buildings 15, no. 4 (December 15, 2019): 315–22. http://dx.doi.org/10.22363/1815-5235-2019-15-4-315-322.
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Relevance. The problems of decline of resource-demanding of objects of building and engineer dictate the necessity of consideration of processes of deformation of constructions at the resiliently-plastic state. The widely in-use theory of account of practical properties of material is a deformation theory of plasticity. The aim of the research is development of variants of receipt of determining correlations on the step of ladening at deformation of material outside a resiliency. Methods. Algorithms over of receipt of determining correlations of theory of small resiliently-plastic deformations are brought on the step of ladening in two variants. In the first they turn out differentiation of expressions of tensions as functions of deformations on the basis of deformation theory of plasticity; in the second determining correlations turn out on the basis of hypothesis about the proportion of components of deviators increases of tensions to components of deviators increases of deformations. Results. On the test example of calculation of the jammed cylindrical shell realization of the got determining correlations is presented.
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Tsareva, Olga, Ivan Dmitriev, and Yuriy Kornilov. "Estimation of absolute deformations by changes in distances between the reference points and deformation marks." MATEC Web of Conferences 245 (2018): 04013. http://dx.doi.org/10.1051/matecconf/201824504013.
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The article considers the definition of absolute types of deformations, such as transfer and rotation of a building, using linear spatial intersection. In particular, knowing the distances between strong points and deformation marks, the coordinates of the marks located on the building in the initial and current observation cycles are obtained. Knowing the coordinates of the marks, calculate the displacement vectors of the marks for a certain period of time. The definition of absolute deformations is based on the estimation of the projections of the displacement vectors on the coordinate axes, as well as the direction cosines of the vectors with the coordinate axes. The determination of the direction of displacement is shown for the transference deformation. And how to determine the axis, the distance to this axis and the angle of rotation is shown for rotation deformation. We show for joint deformation of the transfer and rotation how divide it into components and then determine the direction of displacement and the axis of rotation. The results can be used in assessing of absolute deformations buildings of monuments of cultural heritage.
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Reilinger, Robert. "Geodetic Evidence for Tectonic Deformation in the Eastern United States." Seismological Research Letters 59, no. 4 (October 1, 1988): 314. http://dx.doi.org/10.1785/gssrl.59.4.314.
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Abstract The historic geodetic data base in the eastern United States dates back over 100 years. Although instrumentation and hence measurement precision has improved since the initial observations, the basic techniques [leveling, triangulation, water level gauging] remained unchanged until the recent introduction of space geodesy [Very Long Baseline Interferometry (VLBI), Satellite Laser Ranging (SLR), Global Positioning System (GPS)]. Because of this, it has been possible to compare repeated observations to identify apparent changes in relative positions. Such “changes” can reflect observational errors, non-tectonic movements (water level effects, monument instability, loading, etc.) or tectonic/isostatic deformation. A number of possible deformation features in the eastern U. S. have been reported in the literature, including uplift of the southern Appalachian and Adirondack mountains, doming of the Gulf coast inland of the Mississippi delta, subsidence of Chesapeak Bay and along the coast of Maine, horizontal deformation in New York and Connecticut, and possible fault related deformation near Charleston and in the New Madrid area. Unfortunately, it is not dear to what extent any of these features represent tectonic deformations and hence what their significance may be for the earthquake problem. An important recent development in monitoring regional deformation has been the establishment of the eastern U. S. GPS strain network by the National Geodetic Survey. The network consists of roughly 45 sites uniformly distributed east of the Rocky Mountains. The network was established in 1987 and will be reobserved in 1989. Subsequent reobservations will be made at 2 to 5 year intervals depending on analysis of the early measurements. Given the precision of the GPS measurements (few cm in 3-D relative positions), a considerable time period will be required to detect the subtle deformations expected for this intraplate region. Perhaps more immediate information will result from recent progress in recognizing and correcting systematic errors in the historic geodetic data base. This, together with the newly automated historic data base, and improved techniques for integrating and analyzing these extensive observations, provide the necessary basis for effectively evaluating the deformational features listed above. Given the potential importance of these data for understanding tectonic processes (and the huge expense of collecting these measurements over the pst century), such studies should be an integral part of future earthquake studies in the eastern U. S.
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Zhao, Gang, Liuyu Wang, Kazhong Deng, Maomei Wang, Yi Xu, Meinan Zheng, and Qing Luo. "An Adaptive Offset-Tracking Method Based on Deformation Gradients and Image Noises for Mining Deformation Monitoring." Remote Sensing 13, no. 15 (July 27, 2021): 2958. http://dx.doi.org/10.3390/rs13152958.
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The offset-tracking method (OTM) utilizing SAR image intensity can detect large deformations, which makes up for the inability of interferometric synthetic aperture radar (InSAR) technology in large mining deformation monitoring, and has been widely used. Through lots of simulation experiments, it was found that the accuracy of OTM is associated with deformation gradients and image noises in the cross-correlation window (CCW), so CCW sizes should be selected reasonably according to deformation gradients and noise levels. Based on the above conclusions, this paper proposes an adaptive CCW selection method based on deformation gradients and image noises for mining deformation monitoring, and this method considers influences of deformation gradients and image noises on deformations to select adaptive CCWs. In consideration of noise influences on offset-tracking results, smaller CCWs are selected for large deformation gradient areas, and larger CCWs are selected for small deformation gradient areas. For some special areas, special CCWs are selected for offset-tracking. The proposed method is implemented to simulation and real experiments, and the experiment results demonstrate that the proposed method with high reliability and effectiveness can significantly improve the accuracy of OTM in mining deformation monitoring.
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Yang, Wenqing, Jianlin Xuan, and Bifeng Song. "Experimental Study on Flexible Deformation of a Flapping Wing with a Rectangular Planform." International Journal of Aerospace Engineering 2020 (September 24, 2020): 1–13. http://dx.doi.org/10.1155/2020/8857078.
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A flexible flapping wing with a rectangular planform was designed to investigate the influence of flexible deformation. This planform is more convenient and easier to define and analyzed its deforming properties in the direction of spanwise and chordwise. The flapping wings were created from carbon fiber skeleton and polyester membrane with similar size to medium birds. Their flexibility of deformations was tested using a pair of high-speed cameras, and the 3D deformations were reconstructed using the digital image correlation technology. To obtain the relationship between the flexible deformation and aerodynamic forces, a force/torque sensor with 6 components was used to test the corresponding aerodynamic forces. Experimental results indicated that the flexible deformations demonstrate apparent cyclic features, in accordance with the flapping cyclic movements. The deformations in spanwise and chordwise are coupled together; a change of chordwise rib stiffness can cause more change in spanwise deformation. A certain lag in phase was observed between the deformation and the flapping movements. This was because the deformation was caused by both the aerodynamic force and the inertial force. The stiffness had a significant effect on the deformation, which in turn, affected the aerodynamic and power characteristics. In the scope of this study, the wing with medium stiffness consumed the least power. The purpose of this research is to explore some fundamental characteristics, as well as the experimental setup is described in detail, which is helpful to understand the basic aerodynamic characteristics of flapping wings. The results of this study can provide an inspiration to further understand and design flapping-wing micro air vehicles with better performance.
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Williamson, M., and A. Majumdar. "Effect of Surface Deformations on Contact Conductance." Journal of Heat Transfer 114, no. 4 (November 1, 1992): 802–10. http://dx.doi.org/10.1115/1.2911886.
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This study experimentally investigates the influence of surface deformations on contact conductance when two dissimilar metals are brought into contact. Most relations between the contact conductance and the load use the surface hardness to characterize surface deformations. This inherently assumes that deformations are predominantly plastic. To check the validity of this assumption, five tests were conducted in the contact pressure range of 30 kPa to 4 MPa, with sample combinations of (I) smooth aluminum-rough stainless steel, (II) rough aluminum-smooth stainless steel, (III) rough copper-smooth stainless steel, (IV) smooth copper-rough stainless steel, and (V) smooth aluminum-smooth stainless steel. The experimental results of tests I, II, and IV indicate that the conductance of the first load-unload cycle showed hysteresis, suggesting that the plastic deformation was significant. However, for subsequent load cycles, no conductance hysteresis was observed, implying that elastic deformation was predominant. In contrast, no conductance hysteresis was observed for all load-unload cycles of tests III and V. Therefore, the surface deformation for this combination was always predominantly elastic. In practical applications where plastic deformation is significant for the first loading, mechanical vibrations can produce oscillating loads, which can finally lead to predominance of elastic deformation. Comparison of the results of tests II and V show that even though plastic deformation was significant for the first loading of a rough aluminum surface, elastic deformation was always predominant for the smoother aluminum surface
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Bursnall, J. T., A. D. Leclair, D. E. Moser, and J. A. Percival. "Structural correlation within the Kapuskasing uplift." Canadian Journal of Earth Sciences 31, no. 7 (July 1, 1994): 1081–95. http://dx.doi.org/10.1139/e94-097.
Full textAbstract:
Comparison of progressive deformation and metamorphic history within and between the tectonic domains of the Kapuskasing uplift indicates significant variation in age and style of deformation across this large segment of the central Superior Province; multiple stages of tonalite and granitoid intrusion, melt generation, polyphase diachronous deformation, and likely rapid deep burial of supracrustal rocks collectively produced the complex character of this example of Archean mid to deep crust. At least four Archean deformation phases are recognized, although not all are of regional extent. Dated structural chronology suggests that the locus of the earliest recorded deformations migrated to deeper crustal levels with time. Pre-2680 Ma deformation (local D1–D2) within high-level tonalites is correlated with deformation in the Michipicoten supracrustal belt. The apparent earliest deformational fabrics at deeper crustal levels in the granulite terrane of the Kapuskasing structural zone occurred between 2660 and 2640 Ma. Archean third and fourth phase deformation phases (~ 2667 to ~ 2629 Ma) are present at mid-crustal and deeper levels and deform post-2667 Ma metaconglomerate; these resulted in large-scale folding and subhorizontal ductile shear zones, which seem to represent an important transitional zone that separated a passive upper crust from continued ductile strain at deeper levels.Subsequent uplift of the high-grade rocks was accomplished in multiple stages, initiated prior to 2.45 Ga and likely culminated around 1.9 Ga, although continued movement occurred as late as 1.14 Ga. The Ivanhoe Lake fault zone, along which much of the uplift must have occurred, exhibits some evidence of ductile deep-thrust-related fabrics, but most of the observed structures are brittle to brittle–ductile and steeply inclined. A broad zone of pervasive cataclasis and brittle–ductile shear zones is a characteristic feature of the fault zone throughout its length, and both dextral and sinistral offset are locally present. Clear ground evidence for major transcurrent or thrust displacements, however, has not been recognized.
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Liang, Wei, and Hidekazu Murakawa. "Predicting Welding Distortion in a Panel Structure with Longitudinal Stiffeners Using Inherent Deformations Obtained by Inverse Analysis Method." Scientific World Journal 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/601417.
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Welding-induced deformation not only negatively affects dimension accuracy but also degrades the performance of product. If welding deformation can be accurately predicted beforehand, the predictions will be helpful for finding effective methods to improve manufacturing accuracy. Till now, there are two kinds of finite element method (FEM) which can be used to simulate welding deformation. One is the thermal elastic plastic FEM and the other is elastic FEM based on inherent strain theory. The former only can be used to calculate welding deformation for small or medium scale welded structures due to the limitation of computing speed. On the other hand, the latter is an effective method to estimate the total welding distortion for large and complex welded structures even though it neglects the detailed welding process. When the elastic FEM is used to calculate the welding-induced deformation for a large structure, the inherent deformations in each typical joint should be obtained beforehand. In this paper, a new method based on inverse analysis was proposed to obtain the inherent deformations for weld joints. Through introducing the inherent deformations obtained by the proposed method into the elastic FEM based on inherent strain theory, we predicted the welding deformation of a panel structure with two longitudinal stiffeners. In addition, experiments were carried out to verify the simulation results.
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Eriksen, Eivind. "Computing Noncommutative Deformations of Presheaves and Sheaves of Modules." Canadian Journal of Mathematics 62, no. 3 (June 1, 2010): 520–42. http://dx.doi.org/10.4153/cjm-2010-015-6.
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AbstractWe describe a noncommutative deformation theory for presheaves and sheaves of modules that generalizes the commutative deformation theory of these global algebraic structures and the noncommutative deformation theory of modules over algebras due to Laudal.In the first part of the paper, we describe a noncommutative deformation functor for presheaves of modules on a small category and an obstruction theory for this functor in terms of global Hochschild cohomology. An important feature of this obstruction theory is that it can be computed in concrete terms in many interesting cases.In the last part of the paper, we describe a noncommutative deformation functor for quasi-coherent sheaves of modules on a ringed space (X,𝒜). We show that for any good A-affine open cover U of X, the forgetful functor QCoh𝒜 → PreSh(U,𝒜) induces an isomorphism of noncommutative deformation functors.Applications. We consider noncommutative deformations of quasi-coherent 𝒜-modules on X when (X,𝒜) = (X,𝒪X) is a scheme or (X,𝒜) = (X,𝒟) is a D-scheme in the sense of Beilinson and Bernstein. In these cases, we may use any open affine cover of X closed under finite intersections to compute noncommutative deformations in concrete terms using presheaf methods. We compute the noncommutative deformations of the left 𝒟X-module 𝒟X when X is an elliptic curve as an example.
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Malik, T., Ya Bryk, V. Zatserkovnyi, and V. Belenok. "EVALUATION OF ENGINEERING STRUCTURES DEFORMATION (ACCURACY)." Visnyk of Taras Shevchenko National University of Kyiv. Geology, no. 1 (84) (2019): 77–82. http://dx.doi.org/10.17721/1728-2713.84.11.
Full textAbstract:
The construction of the model of accuracy of the measuring processes of the automated monitoring system of engineering structures deformations from the point of the theory of accuracy is considered in the article. From the point of view of the generalization of the accuracy of measurements by the automated system of engineering structures monitoring, the construction of the model of the measuring process is considered, resulting in separate characteristics and properties of the object to be investigated. In this case these are values of deformations of engineering constructions' structures. The brief acquaintance with the automated system of monitoring of engineering structures deformations, which represents a chain of optoelectronic devices-deformation marks, which are installed on constructions of structures and fix the created line is given. The use of this system allows to solve the problem of the preventive assessment of the dynamics of local technogenic deformation in the engineering structure and thus to increase the level of technogenic safety of the personnel of the engineering structure. Compared with modern well-known methods and means for determining the engineering structures deformation, an automated deformation monitoring system has the following advantages: 1. Cross-section geodetic control of deformations (position) of elements of the full volume of engineering structure with increased accuracy. 2. Automated control of engineering structures deformations in real time, including in limited or inaccessible for visual measurements places. 3. Control of the technogenic safety of the engineering structure, prediction of the moment of the emergency, warning about the upcoming critical state (moment) of the engineering structure in real time with the accurate definition of a certain area. 4. Installation of the entire monitoring system occurs during the construction of the structure, pre-installation sites of optoelectronic devices - deformation marks are agreed with the designers and architects. 5. The mean square error of measurement of relative deviations of deformations is not less than 0,1-0,5 mm at distances between optoelectronic devices up to 10 m. 6. Information on the magnitude of deviations from the nominal (initial) position goes to the remote central control panel of the system in real time scale. 7. In the case of upcoming moment of dangerous deviation (deformation), the command from the main control panel receives a signal for rapid response with the accurate designation of the place of dangerous deformation.