Journal articles: 'Spring wall'

1

Si, Lin Jun, Gong Lian Chen, and Hua Li Wang. "Three-Spring Model for Spatial Walls." Applied Mechanics and Materials 238 (November 2012): 652–58. http://dx.doi.org/10.4028/www.scientific.net/amm.238.652.

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Shear wall structures, frame-shear wall structures and frame-tube wall structures are usually used in tall buildings, especially in China seismic regions. How to simulate the mechanical behaviors of these walls is the key to elastic-plastic analysis for tall buildings. Based on two-spring model, a nonlinear model for spatial walls is proposed. In this model, the axial, shear and flexural elastic-plastic deformation of the walls can be considered, the deformation compatibility between the wall and beam elements is also considered. The model was used to analysis the elastic-plastic behavior of spatial walls. Calculation example for verifying the model indicates that the result obtained by this method has the characteristics of fewer degrees of freedom and high accuracy. Therefore the nonlinear model for spatial walls provides a practical and efficient analysis method for tall buildings with complex type.

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Jeong, Seong-Hoon, and Won-Seok Jang. "Modeling of RC shear walls using shear spring and fiber elements for seismic performance assessment." Journal of Vibroengineering 18, no. 2 (March 31, 2016): 1052–59. http://dx.doi.org/10.21595/jve.2015.16757.

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Reinforced concrete shear wall is one of the most effective members during severe lateral loads especially in earthquakes and winds. Extensive researches, both analytical and experimental, have been carried out to study the behavior of reinforced concrete (RC) shear walls. Predicting inelastic response of RC walls and wall systems requires accurate, effective, and robust analytical model that incorporate important material characteristics and behavioral response features. In this study, a modeling method using fiber and spring elements is developed to capture inelastic responses of an RC shear wall. The fiber elements and the spring reflect flexural and shear behaviors of the shear wall, respectively. The fiber elements are built by inputting section data and material properties. The parameters of the shear spring that represent strength and stiffness degradation, pinching, and slip are determined based on analysis results from a detailed finite element method (FEM) model. The reliability of the FEM analysis program is verified. The applicability of the proposed modeling method is investigated by performing inelastic dynamic analyses for reference buildings with various aspect ratios of shear walls.

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Welty, Emily E. "Occupy Wall Street as “American Spring”?" Peace Review 26, no. 1 (January 2014): 38–45. http://dx.doi.org/10.1080/10402659.2014.876311.

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Mogilevich, L. I., V. S. Popov, A. A. Popova, and A. V. Khristoforova. "Mathematical Simulation of Nonlinear Vibrations of a Channel Wall Interacting with a Vibrating die Via Viscous Liquid Layer." Herald of the Bauman Moscow State Technical University. Series Instrument Engineering, no. 2 (139) (June 2022): 26–41. http://dx.doi.org/10.18698/0236-3933-2022-2-26-41.

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The article considers the developed mathematical model and investigates the dynamics of the interaction of a channel wall supported by a nonlinear spring with a vibrating opposite wall through a viscous fluid layer filling the channel. A flat slotted channel formed by two absolutely rigid rectangular walls, parallel to each other was investigated. One of the channel dimensions in the plan was much larger than the other, which leads to the transition to a plane problem. The bottom channel wall rested on a spring with a cubic nonlinear characteristic, and the upper wall was a die oscillating according to a given law. The gap between the walls was assumed to be much smaller than the channel longitudinal dimension, and the amplitudes of wall vibrations were much less than the channel gap. The movement of the viscous fluid in the channel was considered to be creeping. The mathematical model of the channel under consideration consisted of an equation of the dynamics of a single-mass system with a spring having a cubic nonlinearity, as well as the Navier --- Stokes and continuity equations, supple-mented by the boundary conditions for fluid nonslip on the channel walls and its free outflow at the ends. The steady-state nonlinear vibrations of the bottom channel wall at the fundamental frequency were studied, and its hydroelastic response was determined. The proposed model can be used to study nonlinear vibrations of elastically fixed elements that are in contact with liquid and are parts of modern devices and assemblies

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Kim, Euiyoung, and Haecheon Choi. "Space–time characteristics of a compliant wall in a turbulent channel flow." Journal of Fluid Mechanics 756 (September 1, 2014): 30–53. http://dx.doi.org/10.1017/jfm.2014.444.

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AbstractThe space–time characteristics of a compliant wall in a turbulent channel flow are investigated using direct numerical simulation (DNS). The compliant wall is modelled as a homogeneous plane supported by spring-and-damper arrays and is passively driven by wall-pressure fluctuations. The frequency/wavenumber spectra and convection velocities of the wall-pressure fluctuations, wall displacement and wall velocity are obtained from the present simulation. As the spring, damping, and tension coefficients decrease, the wall becomes softer and the wall displacement and velocity fluctuations increase. For a relatively stiff compliant wall (i.e. large spring, damping and streamwise tension coefficients), there are few changes in the skin-friction drag and near-wall turbulence structures. However, when a compliant wall is soft (i.e. small spring, damping and streamwise tension coefficients), the wall moves in the form of a large-amplitude quasi-two-dimensional wave travelling in the downstream direction. This wave is generated by the resonance of the wall property and the near-wall flow is significantly activated by this wall motion. The power spectra of wall variables show distinct peaks near the resonance frequencies. The convection velocities of the wall motion and wall-pressure fluctuations become smaller with a softer wall.

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Furukawa, Aiko, Junji Kiyono, and Kenzo Toki. "Proposal of a Numerical Simulation Method for Elastic, Failure and Collapse Behaviors of Structures and its Application to Seismic Response Analysis of Masonry Walls." Journal of Disaster Research 6, no. 1 (February 1, 2011): 51–69. http://dx.doi.org/10.20965/jdr.2011.p0051.

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We propose a dynamic analysismethod – a refined version of the DEM- that can simulate three-dimensional elastic, failure and collapse behaviors of structures. A structure is modeled as an assembly of rigid elements. Interaction between elements is modeled using multiple springs and multiple dashpots attached to surfaces of the elements. The elements are assumed to be rigid, but the method allows the simulation of structural deformation by permitting penetration between elements. There are two types of springs: one is a restoring spring to simulate elastic behavior before failure and the other is a contact spring for simulating contact and recontact between elements. A contact dashpot is also used to dissipate the energy of contact. Structural failure is modeled by replacing restoring springs with contact springs and dashpots. A method for determining spring constants is also proposed. The validity of the method is confirmed by the numerical simulation of masonry wall models. First, the elastic behavior induced by an impact force is calculated. It is found that the elastic behavior determined using the proposed method is in good agreement with that determined using the finite element method. Second, the seismic behaviors of masonry wall models with different laying patterns and a wall model with reinforcement are analyzed. It is found that the proposed method allows expression of the difference in behavior due to different laying patterns and reinforcement. The validity of the proposed method is thus confirmed. The proposed method is suitable for simulating seismic behavior of masonry structures.

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Shah, Kushal, Dmitry Turaev, Vassili Gelfreich, and Vered Rom-Kedar. "Equilibration of energy in slow–fast systems." Proceedings of the National Academy of Sciences 114, no. 49 (November 28, 2017): E10514—E10523. http://dx.doi.org/10.1073/pnas.1706341114.

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Ergodicity is a fundamental requirement for a dynamical system to reach a state of statistical equilibrium. However, in systems with several characteristic timescales, the ergodicity of the fast subsystem impedes the equilibration of the whole system because of the presence of an adiabatic invariant. In this paper, we show that violation of ergodicity in the fast dynamics can drive the whole system to equilibrium. To show this principle, we investigate the dynamics of springy billiards, which are mechanical systems composed of a small particle bouncing elastically in a bounded domain, where one of the boundary walls has finite mass and is attached to a linear spring. Numerical simulations show that the springy billiard systems approach equilibrium at an exponential rate. However, in the limit of vanishing particle-to-wall mass ratio, the equilibration rates remain strictly positive only when the fast particle dynamics reveal two or more ergodic components for a range of wall positions. For this case, we show that the slow dynamics of the moving wall can be modeled by a random process. Numerical simulations of the corresponding springy billiards and their random models show equilibration with similar positive rates.

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8

Wang, Zijun, Xingqiao Ma, Houbing Huang, Hongwen Xiao, and Tianfu Li. "Micromagnetic Simulation of Domain Walls in Exchange Spring Trilayers." Advances in Condensed Matter Physics 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/301063.

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Chiral domain wall structures in ferromagnetic exchange spring soft/hard/soft and hard/soft/hard trilayers were investigated with micromagnetic simulation, which enables us to fully characterize the nucleation and growth of buried domain walls in layered ferromagnetic thin films. Simulated results show that the trilayers are both exchange coupled and presenting chiral spin structures. Detailed features of field-dependent domain walls evolution in the spring magnets are also revealed. In process of remagnetization, the spin structure of soft/hard/soft is energetically more stable than that of hard/soft/hard.

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9

Fredso̸e, J., B. M. Sumer, J. Andersen, and E. A. Hansen. "Transverse Vibrations of a Cylinder Very Close to a Plane Wall." Journal of Offshore Mechanics and Arctic Engineering 109, no. 1 (February 1, 1987): 52–60. http://dx.doi.org/10.1115/1.3256990.

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The paper presents a series of experiments carried out with a cylinder suspended by springs and placed very close to a plane wall. The cylinder is exposed to a steady current. The range of gap ratios between zero and one has been studied in detail. Different combinations of spring stiffness and mass of cylinder is applied in the range of reduced velocity between 2 and 10. The proximity of the wall is shown to have important influence on the behavior of the pipe. Some of these trends are explained by a mathematical model including the effect of lift force close to the wall.

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Chaofeng, Li, Tang Qiansheng, Miao Boqing, and Wen Bangchun. "The sensibility on dynamic characteristics of pre-pressure thin-wall pipe under elastic boundary conditions." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 231, no. 6 (August 9, 2016): 995–1009. http://dx.doi.org/10.1177/0954406216631371.

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Consideration is given to dynamic behavior of cylindrical pressure pipe with elastic boundary conditions. Based on Sanders’ shell theory and Hamilton principle, the system equations are established for integrating the uniform distributed pressure into the elastic boundary condition. In the analytical formulation, the Rayleigh–Ritz method with a set of displacement shape functions is used to deduce mass, damping, and stiffness matrices of the pipe system. The displacements in three directions are represented by the characteristic orthogonal polynomial series and trigonometric functions which are satisfied with the elastic boundary conditions, which are represented as four sets of independent springs placed at the ends including three sets of linear springs and one set of rotational spring. The pressure pipe always suffers a uniform distributed pressure in radial direction. To verify the accuracy and reliability of the present method, several numerical examples with classical boundary condition, including free and simply supported supports are listed and comparisons are made with open literature. Then the influences of boundary restraint stiffness and the distributed pressure on natural frequency and the forced vibration response are studied: The natural frequencies increase significantly as the restraint stiffness or the distributed pressure increases. Compared to the rotational spring stiffness, the stiffnesses of axial, radial, and circumferential springs have more significant effect on natural frequency. And the lower modes are more sensitive on restraint stiffness than higher modes. But the variation of natural frequency with respect to the spring stiffness decreases monotonically with the increasing distributed pressure. The forced vibration response is also affected by the restraint stiffness.

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11

Shu, Jicheng, Jianping Sun, Dingwen Zhang, and Huanwei Wei. "Sequential Measurement and Analysis of Large Underground Retaining Structures by Diaphragm Wall Anchor for the Spring Area." Advances in Civil Engineering 2019 (November 11, 2019): 1–21. http://dx.doi.org/10.1155/2019/5291420.

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The performance of a diaphragm wall-anchor structure in spring area in Jinan city, China, is studied. Based on field measured data, lateral wall deflections, lateral soil movements, horizontal displacement of the capping beam, the maximum lateral wall deflection, ground surface settlement, lateral earth pressures on diaphragm wall, internal force of diaphragm wall, axial anchoring forces, settlements of adjacent building, and pore-water pressure are investigated. The results indicate that the maximum deflections of the lateral wall are 0.07%∼0.18% of the excavation depth (He). The ground surface settlement influence zone extends beyond 2.5He from the pit for this project. The δv,max ranges from 0.67 δh,max to 1.0 δh,max. The maximum lateral active earth pressures on diaphragm walls above the excavation bases range between 0.4He and 0.6He. The axial anchoring forces of the top three layers of anchors change significantly during the excavation while the axial anchoring force of the fourth layer of anchor is constant. The deformation of surrounding building has three stages, including a uniform subsidence stage, an accelerated subsidence stage, and a stable subsidence stage.

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12

GUAUS, ANAÏS, CHRISTOPHE AIRIAU, ALESSANDRO BOTTARO, and AZEDDINE KOURTA. "Effects of wall compliance on the linear stability of Taylor–Couette flow." Journal of Fluid Mechanics 630 (July 10, 2009): 331–65. http://dx.doi.org/10.1017/s0022112009006648.

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The stability of the laminar flow in the narrow gap between infinitely long concentric cylinders, the inner of which rotates, is examined for the case of compliant bounding walls, modelled as thin cylindrical shells supported by rigid frames through arrays of springs and dampers. Sufficiently soft walls have a destabilizing influence on the axisymmetric Taylor vortices produced by the centrifugal force, although the effect is limited to modes with large axial wavelengths. Due to the walls flexibility, hydroelastic modes are generated. Complex modal exchanges are observed, as function of the wall properties and the Reynolds number. For axisymmetric modes an asymptotic analysis is conducted in the limit of small axial wavenumber, to show the correspondence between such exchanges and singularities in the analytical solutions. While the axisymmetric modes dominate the spectrum when the walls are rigid or very mildly compliant, a critical non-zero azimuthal wavenumber exists for which the hydroelastic modes become more unstable. Shorter azimuthal waves are favoured by increasing spring stiffness.

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13

XU, S., D. REMPFER, and J. LUMLEY. "Turbulence over a compliant surface: numerical simulation and analysis." Journal of Fluid Mechanics 478 (March 10, 2003): 11–34. http://dx.doi.org/10.1017/s0022112002003324.

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In this paper we present results from a numerical investigation of turbulent channel flow in the presence of a compliant wall. The compliant wall is modelled as a homogeneous spring-supported plate. The simulation code is validated both by comparison with an alternative code and by reproducing results of linear stability theory. Our results demonstrate that with the wall compliance we used in the simulation there is little change in the very long-time behaviour of the turbulent skin friction drag and little modification to the near-wall turbulent coherent structures. The values of pertinent statistical quantities of the turbulence near the compliant walls converge to those near a rigid wall and the statistical effect of the wall compliance on the turbulent channel flow is small.

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14

Pease, F., AJ Ward, AJ Stevenson, JL Cunningham, O. Sabri, M. Acharya, and TJS Chesser. "Posterior wall acetabular fracture fixation: A mechanical analysis of fixation methods." Journal of Orthopaedic Surgery 27, no. 3 (July 16, 2019): 230949901985983. http://dx.doi.org/10.1177/2309499019859838.

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Stable, anatomical fixation of acetabular fractures gives the best chance of successful outcome, while penetration of the acetabular articular surface with screws is associated with poor outcomes. Spring plates are an alternative to interfragmentary lag screws when penetration is a concern. A mechanical study comparing fracture stability and construct stiffness of three fixation methods for posterior wall acetabular fractures with transverse comminutions was performed. The three fixation methods tested were a posterior wall rim plate, a posterior wall buttress plate with separate lag screws and a posterior wall plate with two spring plates. Nine samples were tested, three for each fixation method. Two-dimensional motion analysis was used to measure fracture fragment displacement and construct stiffness. After two 6000 cycle-loading protocols, to a maximum 1.5 kN, the mean fracture displacement was 0.154 mm for the rim plate model, 0.326 mm for the buttress plate and 0.254 mm for the spring plate model. Mean maximum displacement was significantly less for the rim plate fixation than the buttress plate ( p = 0.015) and spring plate fixation ( p = 0.02). The rim plate was the stiffest construct 10,962 N/mm, followed by the spring plate model 5637 N/mm and the buttress plate model 4882 N/mm. Based on data obtained in this study, where possible a rim plate with interfragmentary lag screws should be used for isolated posterior wall fractures as this is the stiffest and most stable construct. When this method is not possible, spring plate fixation is a safe and a superior alternative to a posterior buttress plate method.

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Wang, Zi Jun, Tian Fu Li, Hong Wen Xiao, Yun Tao Liu, and Xing Qiao Ma. "Micromagnetic Simulation of Magnetic Structure in an Exchange-Coupled Trilayer." Applied Mechanics and Materials 521 (February 2014): 543–46. http://dx.doi.org/10.4028/www.scientific.net/amm.521.543.

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The reversal process of an exchange spring trilayer was studied by micromagnetic simulation, simulating the hysteresis loop and magnetic domain wall structure of a soft/hard/soft ferromagnetic exchange spring. The exchange spring effect was observed, determining the chirality of its spiral magnetization configuration. By simulation of the domain wall structure, we find that reversal nucleation emerge simultaneously in either surface of two soft layers and the magnetic moments of hard layer start rotation at reversible stage.

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Chong, Xun, Xian Guo Ye, De Cai Wang, and Xing Lian. "Seismic Response of Superposed Wall Panel with Different Edge Components." Advanced Materials Research 163-167 (December 2010): 1074–79. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.1074.

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Seismic performance of a kind of superposed wall, which is composed of two precast panels and the cast- in- place core concrete, was studied in the paper. Two groups of superposed wall units with different edge elements were constructed and tested under quasi- static reversed cyclic loading. The strength, stiffness, ductility, energy dissipation and failure modes of the walls under lateral load were investigated, and the influence of different edge elements to the seismic response of the wall panels was discussed. Moreover, numerical simulation analysis was conducted applying multi- spring (MS) model with the finite element analysis procedure CANNY. Results of the inelastic analysis were compared with the experimental ones to validate the reasonability of the numerical model and evaluate the seismic response of superposed walls further.

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Barulina, Marina, Loredana Santo, Victor Popov, Anna Popova, and Dmitry Kondratov. "Modeling Nonlinear Hydroelastic Response for the Endwall of the Plane Channel Due to Its Upper-Wall Vibrations." Mathematics 10, no. 20 (October 17, 2022): 3844. http://dx.doi.org/10.3390/math10203844.

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A mathematical model for studying the nonlinear response of the endwall of a narrow channel filled with a viscous fluid to the vibration of the channel’s upper wall was formulated. The channel, formed by two parallel, rigid walls, was investigated. The right end-channel wall was supported by a nonlinear spring. At the end of the left channel, the fluid flowed into a cavity with constant pressure. The upper channel wall oscillated according to a given law. As a result of the interaction between the endwall and the upper wall via a viscous fluid, the forced, nonlinear oscillations of the channel endwall arose. The fluid motion was considered in terms of the hydrodynamic lubrication theory. The endwall was studied as a spring-mass system with a nonlinear cubic restoring force. The coupled hydroelasticity problem was formulated, and it was shown that the problem under consideration was reduced to a single equation in the form of the Duffing equation. The nonlinear hydroelastic response of the end wall was determined by means of the harmonic balance method. The results of numerical experiments on nonlinear hydroelastic response behavior and a comparison with the case when the support spring is linear were presented. The obtained results are of a fundamental nature and can be used in modeling various devices and systems that have narrow channels filled with viscous fluid and are subjected to vibrations on one side of the channel. For example, coolant pipes are subjected to vibrations from the engine. Of particular interest is the application of the presented solution to the mathematical modeling of nano- and micro-spacecraft systems with fluids since the proposed decision allows for the consideration of some boundary effects, which is important for nano- and micro-spacecraft due to their small size.

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Madadi-Kandjani, Ehsan, and Qingang Xiong. "Validity of the spring-backed membrane model for bubble–wall interactions with compliant walls." Computers & Fluids 96 (June 2014): 116–21. http://dx.doi.org/10.1016/j.compfluid.2014.03.010.

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Zhao, Yanzheng, Zhuang Fu, Qixin Cao, and Yan Wang. "Development and applications of wall-climbing robots with a single suction cup." Robotica 22, no. 6 (November 2004): 643–48. http://dx.doi.org/10.1017/s0263574704000517.

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In this paper, wall-climbing robots with a single suction cup are studied. The robots mainly consist of three parts: A vacuum pump, a sealing mechanism and a driving mechanism. Basic conditions that the robots can adhere to and move reliably on a vertical surface are first established, then the sealing mechanism with an air spring and regulating springs is analyzed, and the synthetic rigidity formula for the sealing loop is obtained. Finally, two application examples are given: One for the ultrasonic inspection of cylindrical stainless steel nuclear storage tanks, and the other for cleaning high-rise buildings.

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Kovanič, Ľudovít, and Peter Blišťan. "Quarry Wall Stability Assessment Using TLS Method." Advanced Materials Research 1044-1045 (October 2014): 603–6. http://dx.doi.org/10.4028/www.scientific.net/amr.1044-1045.603.

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The aim of this paper is to test the possibility of terrestrial laser scanning use to analyze the stability of quarry walls. In recent years the laser scanners started being tested and used for the documentation of geological structures and various phenomena such as landslides, rock collapses and observation of their morphological changes. The subject of our research was a quarry wall in the open-pit mine Brestov, with a significant bench or block disintegration of the andesite massif and therefore, there is a risk of rock blocks crashing. Selected quarry wall was repeatedly measured in the autumn and spring season by a terrestrial laser scanner and movements of rock blocks were evaluated. The observation results show that on the selected quarry wall there were no major movements or block collapse detected and the wall is stable after the winter shutdown.

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Akasaka, T., M. Katoh, S. Nihei, and M. Hiraiwa. "Two-Dimensional Contact Pressure Distribution of a Radial Tire." Tire Science and Technology 18, no. 2 (April 1, 1990): 80–103. http://dx.doi.org/10.2346/1.2141696.

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Abstract Two-dimensional contact pressure distribution of a radial tire, statically compressed to a flat roadway, is analyzed using a rectangular contact patch. The tire structure is modeled by a spring-bedded ring belt comprised of a laminated-biased composite strip. The belt is supported by radial springs simulating the sidewall. The spring constant Kr was well defined previously by one of the authors. Deformation of the rectangular flat belt is obtained theoretically. The belt is subjected to inflation pressure, reaction forces transmitted from the spring bed of the tread rubber, and shearing force and bending moment along the belt boundaries brought from side-wall springs and the detached part of the ring belt. In-plane membrane forces, which are not uniform in the contact area, due to the friction forces acting between the tread surface and the roadway are also applied. The resulting contact pressure distributions in the circumferential direction are shown to be convex along the shoulder, but concave along the crown center line. This distribution agrees well with the experimental results.

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De Mauro, Domenico, Giuseppe Rovere, Lorenzo Are, Amarildo Smakaj, Alessandro Aprato, Umberto Mezzadri, Federico Bove, et al. "Spring Plates as a Valid Additional Fixation in Comminuted Posterior Wall Acetabular Fractures: A Retrospective Multicenter Study." Journal of Clinical Medicine 12, no. 2 (January 11, 2023): 576. http://dx.doi.org/10.3390/jcm12020576.

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Background: The posterior wall fracture is the most frequent pattern of acetabular fractures. Many techniques of fixation have been described in the literature and involve plates, screws, or a combination of both. This study aims to investigate the clinical and radiological outcomes of spring plates in the treatment of comminuted posterior wall acetabular fractures. (2) Methods: A retrospective multicenter (four level I trauma centers) observational study was performed. Patients with a comminuted posterior wall acetabular fracture treated with a spring plate (DePuy Synthes, West Chester, PA) were included. Diagnosis was made according to the Judet and Letournel classification. Diagnosis was confirmed with plain radiographs in an antero-posterior view and Judet views, iliac and obturator oblique views, and thin-slice CT with multiplanar reconstructions. (3) Results: Forty-six patients (34 males and 12 females) with a mean age of 51.7 years (range 19–73) were included. The most common mechanism of injury was motor vehicle accident (34 cases). In all cases, spring plates were placed under an overlapping reconstruction plate. The mean follow-up was 33.4 months (range 24–48). The mean period without weight-bearing was 4.9 weeks (range 4–7), and full weight-bearing was allowed at an average of 8.2 weeks (range 7–11) after surgery. (4) Conclusions: According to the present data, spring plates can be considered a viable additional fixation of the posterior wall acetabular fractures.

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Li, Jia Lu, Ai Guo Song, and Xiao Rui Zhang. "Stability Analysis and Improvement of Virtual Wall Model." Key Engineering Materials 464 (January 2011): 183–86. http://dx.doi.org/10.4028/www.scientific.net/kem.464.183.

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Sampled-data system’s nature is the main factor that causes virtual wall to demonstrate active (non-passive) behavior, destroying the illusion of reality. To enhance the stability of haptic rendering by virtual wall model, a novel spring-impulse model based on energy conversation and momentum conversation is proposed. In the model, an impulse in the opposite direction of avatar’s velocity is exerted on avatar at the instant from inner of virtual wall back to balance position during unstable state. This resistant forces eliminate extra work to reduce the non-passive behaviors of the haptic system, which lead to improved realistic rigid perceptions and system stability. The experiments have verified the effectiveness of our spring-impulse method in a virtual stiff-wall prototype system via a Phantom Omni haptic device.

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Štaffenová, Daniela, Pavol Durica, Peter Juras, and Ján Rybárik. "Evaluative Case Study in Lightweight Wooden Wall Research." Applied Mechanics and Materials 887 (January 2019): 56–63. http://dx.doi.org/10.4028/www.scientific.net/amm.887.56.

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This presented article deals with two newly designed experimental walls with different measuring sections (5 for each lightweight wooden wall). All fragments meet the standards required for zero and energy-plus buildings, which would be mandatory in Slovakia from the year 2020. The experimental walls are located in central Europe (town Zilina, Slovakia). Description of individual test sections, the measuring technology, data collection, interior technical equipment and outdoor boundary conditions monitoring are introduced. In the future, the experimental research should progressively combine theoretical calculations with real measurement and computer HAM simulation. In this paper, the focus is aimed to the temperature profiles in wall fragments during seven days chosen from the spring period in the year 2017. The results were graphically presented and evaluated from a point of view of continuous temperature measurement in the structure, exterior boundary conditions, wall orientation and surface character (material, color). Also further intensions of research are drawn.

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Chong, Xun, Linlin Xie, Xianguo Ye, Qing Jiang, and Decai Wang. "Experimental study and numerical model calibration of full-scale superimposed reinforced concrete walls with I-shaped cross sections." Advances in Structural Engineering 19, no. 12 (July 28, 2016): 1902–16. http://dx.doi.org/10.1177/1369433216649392.

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The superimposed reinforced concrete wall in which both the walls and slabs are semi-precast superimposed reinforced concrete components has been widely used to construct high-rise residential buildings in some seismic regions of China. This article aims to investigate the seismic performance and reveal the inherent damage mechanism of this wall. Quasi-static tests of two full-scale superimposed reinforced concrete walls with I-shaped cross sections, consisting of the walls in orthogonal directions and two T-shaped cast-in-place boundary elements, were conducted. Through the test, the behavior of the horizontal joints between the wall panels and the foundation; the behavior of the vertical connections between the wall panels of orthogonal direction; the reliability of the connections between precast and cast-in-place concrete; and the lateral load, deformation, and energy dissipation capacities of the specimens are evaluated. In addition, a refined numerical model based on the multi-spring model was adopted to assess the seismic performance of the superimposed reinforced concrete walls with I-shaped cross sections. The reliability of this model was validated through comparison with the experimental data. This study offers valuable experimental data and numerical model references for future seismic performance assessments of superimposed reinforced concrete wall structures.

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Gaurav, Ashwini, Kaushlendra Kumar, and RanjitKumar Singh. "Spring plate for fixation of comminuted posterior wall acetabular fractures." Journal of Orthopaedic Diseases and Traumatology 5, no. 1 (2022): 14. http://dx.doi.org/10.4103/jodp.jodp_25_21.

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Brink, G. E., and T. E. Fairbrother. "Cell Wall Composition of Diverse Clovers during Primary Spring Growth." Crop Science 34, no. 6 (November 1994): 1666–71. http://dx.doi.org/10.2135/cropsci1994.0011183x003400060045x.

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28

Wodzicki, Tomasz J., Krzysztof Rakowski, Zofia Starck, Jarosław Porandowski, and Stefan Zajączkowski. "Apical control of xylem formation in the pine stem. I. Auxin effects and distribution of assimilates." Acta Societatis Botanicorum Poloniae 51, no. 2 (2014): 187–201. http://dx.doi.org/10.5586/asbp.1982.017.

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The effect of IAA upon cambial activity, xylem differentiation and translocation of assimilates from the lateral shoot was investigated in spring and late summer in decapitated and ring-barked young trees of <em>Pinus silvestris</em> in the forest stand. Decapitation interrupted cambial xylem production in the uppermost part of the main stem of decapitated trees in spring and late summer, regardless of whether lateral branches below were growing, dormant or disbudded, and the contact through phloem with the roots was maintained or severed. Auxin supplied to the decapitated stems caused an increasing stimulation of cambial xylem production in spring. It also stimulated cambial activity in August but was ineffective in September. Apical control of cambial xylem production was strongly dependent upon the continuity of phloem and/or cambial tissues of the decapitated main-stem-section with lower parts of the plant. Decapitation of the stem strongly reduced the daily rate of cell wall deposition in the cambial xylem derivatives which on the day the experiment started constituted the zones of radial enlargement and maturation. This reduction limited progressively secondary wall deposition in consecutive maturing tracheids even though the cells differentiated longer. Irrespective of the season, auxin prevented the effect of decapitation in cells which were already differentiating when the experiment started as well as extension of the maturation phase. The effect of auxin was somewhat reduced when the lateral branches were additionally decapitated in early summer. In early summer auxin caused a significant increase of the daily rate of cell wall deposition in cells of the cambial zone or the newly produced ones, thus resulting in formation of progressively thicker secondary walls. Late in summer assimilates were transported mostly to the lower part of the stem. Decapitation changed the intact tree pattern of assimilate distribution, increasing the transport in spring and reducing it later in the summer. Prevention of the contact with roots via phloem and cambium in spring (by ring-barking the stem at tree base) decreased decapitation-induced downward transport of assimilates. Application of auxin to the decapitated uppermost segment of the main stem resulted in a significant increase of assimilate translocation into the stem. At least two mechanisms of auxin involvement in regulation of the rate of secondary wall deposition in pine stem tracheids can be considered: (a) induction (or activation) of the cell wall metabolic potential which seems to occur during meristematic or early radial enlargement phases of tracheid differentiation, and (b) regulation of substrate availability during the phase of tracheid maturation.

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Tikhomirov O.A. "Exchange spring-like inhomogeneous states in a ferromagnetic wire with current." Physics of the Solid State 64, no. 10 (2022): 1444. http://dx.doi.org/10.21883/pss.2022.10.54234.331.

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Transverse structure of magnetization in a ferromagnetic film induced by magnetic field of electric current has been analyzed. Two steps of arising exchange spring evolution are shown. The first one (weak current) is gradual twisting of magnetization aside from the wire axis. Above some critical current the transient area is compressed and localized near the middle plane. In presence of additional conductive layer the transient structure becomes asymmetric resulting to non-zero lateral component of the net magnetization. It is shown also that the mentioned asymmetry can provide additional displacement of domain walls after the electric current pulses. Keywords: spintronics, domain wall dynamics, exchange spring, ferromagnet.

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Prastiyo, Adi, Dwi Irawan, and Kemas Ridhuan. "Analisa pengaruh variasi berat roller dengan pegas CVT terhadap kinerja mesin sepeda motor matic 113 cc." ARMATUR : Artikel Teknik Mesin & Manufaktur 1, no. 1 (April 3, 2020): 1–7. http://dx.doi.org/10.24127/armatur.v1i1.184.

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As the emergence of vehicles that use the CVT transmission system (Countinuesly Variable Transmission) or better known as the automatic motor. The automatic motor has a CVT roller and spring. Roller weight is a weight balance bearing that is useful for pressing the inner wall of the primary pulley when high rotation occurs, and a CVT spring is a spring whose function is to return the secondary pulley to its initial position or the position of the outer belt. The purpose of this study was to determine the effect of CVT springs with roller weight on the performance of the 113 CC automatic motorcycle engine and the effect on specific fuel consumption. In this study the type of vehicle used is Yamaha Mio Sporty 113 CC motorcycle, and the variation of CVT springs with roller weight used is CVT Spring 2.26 N / mm, 2.45 N / mm, and 2.67 N / mm, with a roller weight of 7 grams, 10.5 grams and 14 grams. The testing method used is to test torque and power with dynotest tools to determine the torque and power obtained, as well as acceleration testing to determine the ratio of speed on each variation of CVT springs to roller weight, and specific fuel consumption. From the research that has been done, the results are for the highest torque value obtained in the CVT spring 2.26 N / mm with a 7 gram roller that is 6.14 Nm at 5095 engine rpm, and the highest power in the CVT spring 2.26 N / mm with 7 and 14 gram rollers are 4.9 Hp with a maximum engine rpm of 9250, the best acceleration on a 2.67 N / mm CVT spring with a 14 gram roller that is 201 meters away with 12.63 seconds, and specific fuel consumption is saved on a 2.26 N / mm CVT spring with a 7 gram roller which is 1.98 kg / hour or equivalent to 2.45 ml / s.

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Huang, Xudong, Zhiping Zeng, Zhuang Li, Weidong Wang, Yu Yuan, Weidong Yuan, and Houdou Saidi Boumedienne. "Comparative Research on Vibration Characteristics of Cast-In-Place Steel-Spring-Floating Slab Track under Different Subway Line Conditions." Applied Sciences 12, no. 10 (May 18, 2022): 5079. http://dx.doi.org/10.3390/app12105079.

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Purpose: Steel-spring-floating slab tracks are widely used in subway lines. It is necessary to analyze and study the vibration damping and transmission characteristics of the steel-spring-floating slab track in various frequency bands under the action of train loads. Method: A steel-spring-floating slab track and ordinary monolithic track tunnel sites with similar line conditions on straight and curved segments were selected. The vibration signals of rail, track bed, and tunnel walls were collected and the analysis results of vibration damping and vibration transmission between the steel-spring-floating slab track and the ordinary monolithic track were compared. Results: The dynamic responses of the rail in the four working conditions are relatively close, and the acceleration of the steel-spring-floating slab track bed is significantly larger than that of the ordinary monolithic track. The vibration response generated in the curved segment is significantly greater, and each frequency band will generate more peak points, and the high-frequency vibration will be more severe. Conclusions: The steel-spring-floating slab track can significantly reduce the acceleration response of the tunnel wall; the bottom constraint of the steel-spring-floating slab track is less, and the vibration response of the track bed is more severe.

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Hu, Xiao Yong, Xiao Xu Zhang, Yu Liang Qiu, Wei Hua Dong, and Bao Wen Kou. "Seismic Analysis of Immersed Tube Tunnel for Hong Kong-Zhu Hai-Macao Bridge Project." Advanced Materials Research 250-253 (May 2011): 1723–27. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.1723.

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A simplified seismic calculation model of immersed tunnel is built up, which is applied to the seismic analysis of Hong Kong-Zhu Hai-Macao Bridge Project’s immersed tube tunnel. According to different spring stiffness of foundation and different spring stiffness of joint, the tunnel and joint’s force and deformation conditions are compared. The results show that: the influence of foundation spring stiffness is significant, for engineering design, the foundations of a more flexible approach should be preferred; contrary to joint force, the joint opening increases with the increase of joint stiffness, thus, flexible joint is better for project; the connection parts of floor and wall, the connection parts of roof and wall are the most disadvantageous position during the earthquake, so, these parts’ design strength should be strengthened and deformation control should be taken.

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Thumma, Samuel A. "“Mending Wall” and Negligence: How a Poem can Inform the Common Law." Journal of Tort Law 11, no. 2 (October 25, 2018): 209–30. http://dx.doi.org/10.1515/jtl-2018-0012.

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AbstractUsing selected lines from Robert Frost’s poem Mending Wall, this essay seeks to show how the poem can inform the common law of negligence.Best known for its line “good fences make good neighbors,” Mending Wall involves a narrator recounting his relationship with a neighbor, and the neighbor’s calm persistence that a good boundary wall makes good neighbors. The poem describes how and why, each spring, they walk together to fix a rock wall that is the common boundary of their property. This essay seeks to make the case for how Mending Wall also can inform the common law of negligence.After a discussion of how the author came to write the piece, the essay briefly discusses the context for, and some commentary about, Mending Wall, with the poem included in the Appendix. The essay then provides seven examples of how selected lines from Mending Wall can inform the common law of negligence. Starting with the adage that good fences make good neighbors, the examples help demonstrate when a legal fence needs to be solid and unyielding in delineating the elements of a prima facie negligence claim; when a fence provides an outer boundary for a negligence claim and when a fence is a boundary excluding a negligence claim; when a fence is not needed to define the boundary between types of remedies; how a fence implies a division of labor in what a judge decides and what a jury decides; that the outlier case can try to pull down a fence and, finally, how gaps in a fence are the grist for the mill that is the common law.The essay seeks to show that Mending Wall can be used to help inform the common law of negligence, in certain respects when viewed in a certain way. It does so, the essay suggests, episodically. It provides glimpses and clues, not comprehensive directives, and offers general targets to focus on in the study of common law negligence.Viewed in a concrete way, Mending Wall is about neighbors fixing a stone wall they share on a cold, early spring day. But it is much more than that. In these ways, as the essay suggests, Mending Wall can inform the common law of negligence.

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Mai, Khoi D., William F. Cofer, and Donald A. Bender. "Predicting Behavior of Steel-Clad, Wood-Framed Shear Walls under Cyclic Lateral Loading." Transactions of the ASABE 64, no. 2 (2021): 413–24. http://dx.doi.org/10.13031/trans.14250.

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HighlightsA finite element analysis (FEA) model was developed to predict behavior of steel-clad, wood-framed (SCWF) shear walls under cyclic loading.This FEA model will be useful in determining post-frame building response to seismic forces.The model will save time and money in developing design coefficients and planning experiments for SCWF shear walls.Abstract. This article presents finite element (FEA) model results of steel-clad, wood-framed (SCWF) shear walls under cyclic lateral loading. The shear wall model consists of beam elements to model framing members, equivalent orthotropic plane stress elements to model corrugated steel cladding, linear spring elements to model nail connectors between framing members, and nonlinear hysteresis spring elements to model screw connectors. Screw connectors attaching steel panels to wood framing and steel panels to steel panels at lap joints were tested under cyclic loading to provide the constitutive relationships needed. A modified Bouc-Wen-Barber-Noori (BWBN) model was developed to capture slack, pinching, and strength and stiffness degradation of screw connectors under cyclic loading. The finite element models were validated by comparing them with experimental test results of six different SCWF shear wall configurations. Predicted peak shear strengths for most load cycles were slightly higher than those from the experimental tests, especially for stitched shear walls. Visual inspection of the FEA predicted hysteretic load curves demonstrated that pinching, and strength and stiffness degradation were well captured. The results of this study demonstrate the utility of the FEA model for comparative studies of different SCWF shear wall constructions under cyclic lateral loading. Keywords: Cyclic lateral loading, Diaphragm design, Post-frame building, Steel-clad wood-frame diaphragm.

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Mibu, K., T. Nagahama, T. Ono, and T. Shinjo. "Magnetoresistance of Bloch-Wall-Type Magnetic Structures in Exchange-Spring Bilayers." Journal of the Magnetics Society of Japan 22, no. 4_2 (1998): 613–16. http://dx.doi.org/10.3379/jmsjmag.22.613.

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Watson, S. M., T. Hauet, J. A. Borchers, S. Mangin, and Eric E. Fullerton. "Interfacial magnetic domain wall formation in perpendicular-anisotropy, exchange-spring films." Applied Physics Letters 92, no. 20 (May 19, 2008): 202507. http://dx.doi.org/10.1063/1.2936836.

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Fal, T. J., K. L. Livesey, and R. E. Camley. "Domain wall and microwave assisted switching in an exchange spring bilayer." Journal of Applied Physics 109, no. 9 (May 2011): 093911. http://dx.doi.org/10.1063/1.3573497.

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Ihn, Joo Chul, Poong Taek Kim, and Dong Kyu Shin. "Hooked Spring Plate : Its uses in paterior wall acetabular fracture fixation." Journal of the Korean Society of Fractures 7, no. 2 (1994): 606. http://dx.doi.org/10.12671/jksf.1994.7.2.606.

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Teli, Sujay, Palak Kundhani, Virag Choksi, and KannanK R. Iyer. "Effect of Seismic Analysis Approach and Provision of Shear Walls on Parameters for Raft Foundation Design." Proceedings of the 12th Structural Engineering Convention, SEC 2022: Themes 1-2 1, no. 1 (December 19, 2022): 1831–37. http://dx.doi.org/10.38208/acp.v1.725.

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The present work attempts to understand the effect of different methods of seismic analysis on the design of building raft foundation. The study also evaluates the role of shear wall on the foundation response. A ten storey building with raft foundation has been analyzed in STAAD Pro using three different seismic analysis methods, viz., Linear static analysis, Linear dynamic analysis and Non-linear dynamic analysis. Furthermore, building with two different arrangements of shear walls (peripheral and core region) are studied by Non-linear dynamic analysis and compared with the model without shear wall. The raft is modeled with plate elements supported by soil springs using Winkler's approach. To consider the effect of different soil and raft stiffness, three different soil spring values and two raft thickness values have been considered. It has been concluded from the study that linear static analysis yields lower values of all foundation design parameters (viz., base pressure, settlement, foundation bending moment and shear stress) as compared to dynamic analysis. Dynamic analysis yields higher variation in base pressure and settlement distribution, which suggests adopting dynamic analysis approach for obtaining more realistic response, especially for settlement sensitive structures. Further the provision of shear wall has negligible influence on base pressure and settlement of foundation, while maximum bending moment and shear stress in foundation increases. Hence, provision of shear wall may increase cost of foundation, however, considering its role in improving structural integrity, shear walls are deemed important. Further, the increase in soil stiffness and reduction in raft thickness yields higher maximum base pressure and variation in base pressure, which confirms the importance of considering the effect of soil-foundation interaction for design of foundation. It is opined that the findings of the study would help in more realistic foundation design to achieve better performance during its life cycle.

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Glushkov, Igor, Ilona Zhuravleva, Jessica L. McCarty, Anna Komarova, Alexey Drozdovsky, Marina Drozdovskaya, Vilen Lupachik, Alexey Yaroshenko, Stephen V. Stehman, and Alexander V. Prishchepov. "Spring fires in Russia: results from participatory burned area mapping with Sentinel-2 imagery." Environmental Research Letters 16, no. 12 (November 22, 2021): 125005. http://dx.doi.org/10.1088/1748-9326/ac3287.

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Abstract Human-induced fires play a crucial role in transforming landscapes and contributing to greenhouse gas emissions. Russia is a country where human-induced fires are widespread and form distinctive spring and summer burning cycles. However, spring fires are not well documented and it is unclear which land-cover types are associated with the spread of spring fires. Using Sentinel-2 optical satellite imagery, a wall-to-wall spring burned area data set for 1 January to 15 May 2020 was created for Russia (excluding the Arctic) using a participatory crowdsourcing digitizing approach on an online platform developed specifically for this application. The 2020 spring fire product had a producer accuracy of 85% and user accuracy of 92%. Approximately 13.38 million ha, comprising 1.8% of the study area, were mapped as burned, with the majority of the 2020 spring burned areas in Siberia. Our spring-fire product revealed five times more burned area estimates compared to the burned area estimates from the moderate resolution imaging spectroradiometer (MODIS) MCD64 product. We also found high variability of burned area per active fire pixel across regions of Russia, when compared to MODIS and visible infrared imaging radiometer suite active fire data. Spring fires started to increase from the end of February and reached their maximum by the end of March through the middle of April. Spring fires were associated with arable lands and grasslands as land-cover types, except Siberia, where spring fires were most common in deciduous and needle-leaved forests, followed by arable lands. While spring fires were associated with croplands and grasslands, an estimate for Central Russia showed approximately 75% of spring fires occurred on abandoned agricultural lands. Our study demonstrated the suitability of optical Sentinel-2 imagery for spring fire mapping and the great utility of a participatory mapping approach for fast and accurate mapping as well as engagement of the community.

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Du, Hong Kai, and Miao Han. "Impact and Energy Analysis of Deformation-Limited Base-Isolated Structure in Shaking Table Test." Applied Mechanics and Materials 638-640 (September 2014): 1811–17. http://dx.doi.org/10.4028/www.scientific.net/amm.638-640.1811.

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The deformation of isolation layer in base-isolated building can exceed original design during strong earthquake excitations, which will cause poundings between structure and surrounding retaining wall. Spring limiter installed in base-isolated building can protect the structure. Shaking table test of base-isolated model pounding with spring limiters were performed. The study find the deformation of isolation layer can be effectively reduced by spring limiters, and the deformation of the superstructure will increase slightly. Pounding between structure and spring limiters can arouse high frequency acceleration of building, but had little effect on velocity.Increasing the spring limiters will not change seismic total energy input on the structure, and most of the energy dissipate by the damping. Impact energy dissipation increases with reducing in the gap between structure and spring limiters.

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He, Lan, Kai Leung Yung, Yan Xu, and Yun Wen Shen. "The Effect of Surface Features on Nanorheology of LCP Melts in Nanochannels by MD Simulation." Journal of Tribology 129, no. 1 (September 25, 2006): 171–76. http://dx.doi.org/10.1115/1.2401219.

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The effects of wall surface features on the rheological properties and phase orientation of liquid crystalline polymer (LCP) melts flowing in a nanochannel have been first investigated by molecular dynamics (MD) simulations. The surfaces are modeled as rough atomic serrated walls whereby the roughness is characterized by the period and amplitude of serration. The molecular chains of LCPs are depicted by a newly developed molecular model named the GB-spring-bead model. Through simulating the phase formation of LCP melts, the new model was evaluated and the results have shown the new model is efficient and accurate to describe semi-flexible main-chain LCP molecules. MD simulations of the effect of wall surface features on the LCP shear flow were conducted and the results have revealed the surface features affect greatly the rheological properties and phase orientations of LCP melts in a nanochannel (the distance between the upper wall and the lower wall is 12.8nm). Findings in this study provide very useful information in the injection molding of plastic products with nanofeatures.

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Milesi, Gaétan, Patrick Monié, Philippe Münch, Roger Soliva, Audrey Taillefer, Olivier Bruguier, Mathieu Bellanger, Michaël Bonno, and Céline Martin. "Tracking geothermal anomalies along a crustal fault using (U − Th)∕He apatite thermochronology and rare-earth element (REE) analyses: the example of the Têt fault (Pyrenees, France)." Solid Earth 11, no. 5 (September 14, 2020): 1747–71. http://dx.doi.org/10.5194/se-11-1747-2020.

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Abstract. The Têt fault is a major crustal-scale fault in the eastern Pyrenees (France) along which 29 hot springs emerge, mainly within the footwall damage zone of the fault. In this study, (U-Th)/He apatite (AHe) thermochronology is used in combination with rare-earth element (REE) analyses in order to investigate the imprint of hydrothermal activity around two main hot spring clusters (Thuès-les-Bains and St Thomas) and between them. The main goal is to better define the geometry and intensity of the recent thermal anomalies along the fault and to compare them with previous results from numerical modelling. This study displays 99 new AHe ages and 63 REE analyses on single apatite grains from samples collected in the hanging wall (18 to 43 Ma) and footwall (8 to 26 Ma) of the Têt fault. In the footwall, the results reveal AHe age resetting and apatite REE depletion due to hydrothermal circulation along the Têt fault damage zone, near the two hot spring clusters, and also in areas lacking present-day geothermal surface manifestation. These age resettings and element depletions are more pronounced around the Thuès-les-Bains hot spring cluster and are spatially restricted to a limited volume of the damage zone. Outside this damage zone, new modelling of thermochronological data specifies the thermal evolution of the massifs. The footwall model suggests the succession of two main phases of cooling: between 30 and 24 Ma and a second one around 10 Ma. In the hanging wall, little evidence of hydrothermal imprint on AHe ages and REE signatures has been found, and thermal modelling records a single cooling phase at 35–30 Ma. Low-temperature thermochronology combined with REE analyses allows us to identify the spatial extent of a recent geothermal perturbation related to hydrothermal flow along a master fault zone in the eastern Pyrenees, opens new perspectives to constrain the geometry and intensity of geothermal fields, and provides new regional constraints on the cooling history of the footwall and hanging-wall massifs.

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Phanitwong, Wiriyakorn, and Sutasn Thipprakmas. "Effects of Draw-Bending Characteristics on Concave Wall Feature in Rectangular Deep-Drawn Parts." Key Engineering Materials 549 (April 2013): 92–99. http://dx.doi.org/10.4028/www.scientific.net/kem.549.92.

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In recent years, the requirements on the complicated deep-drawn parts with the high dimension precision are increasingly. As the major defect, the concave wall feature which commonly encounter in the complicated deep-drawn parts of the difficult-to-deep draw material is focused. In this research, the effects of draw-bending characteristics on concave wall feature during deep-drawing process are clearly identified. The mechanism of concave wall feature related to the draw-bending characteristic was investigated and clearly identified by using the finite element method (FEM) and the experiments were also performed to validate the FEM-simulation results. On the basis of stress distribution, the effects of draw-bending characteristics on the concave wall feature could be clearly identified via the changes of stress distributions on the wall, convex feature and spring-go feature on the bottom surface, and spring-back feature on the top surface. However, comparing with U-draw bending model, the effects of draw-bending characteristics was decreased and the concave wall feature in the case of deep-drawing model was smaller than that in the case of U-draw bending model. The experiments were carried out in both cases of the deep-drawing and U-draw bending models to validate the FEM-simulation results. The FEM-simulation results showed a good agreement with the experimental results with reference to the distribution of material thickness.

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Abbasi Maedeh, Pouyan, Ali Ghanbari, and Wei Wu. "Investigation of Soil Structure Interaction and Wall Flexibility Effects on Natural Sloshing Frequency of Vessels." Civil Engineering Journal 3, no. 1 (January 30, 2017): 45–56. http://dx.doi.org/10.28991/cej-2017-00000071.

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The main purpose of this study is to establish the effects of vessel walls flexibility on its natural sloshing frequency considering soil-structure-fluid interaction theory. Furthermore, two new efficiently relations to find both of wall flexibility and soil-structure interaction effects on natural frequency are developed. Regarding the aim of current study three different conditions of elevated tanks are applied. Fixed base condition with an emphasis on recommendations of international code ACI-350, analytical FSSI regarding equivalent mass spring method, and the numerical direct method regarding theory of finite element are taken into consideration. Results indicate that there is no significant effect of walls flexibility on natural sloshing frequency regarding fixed base assumptions of vessels. On the contrary, significant effects of wall flexibility are achieved considering SSI theory. Results of international code ACI-350 show that, the international codes assumptions have imprecise estimations of natural sloshing frequency in the range of hard to very soft soil categories. On the other hand, it is observed that the wall flexibility has a more highlighted effect on natural frequency in soft soils rather than soil-structure interaction. The significance of wall flexibility effect on natural frequency is more than that of SSI considering soil softening.

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Asano, Yoshihiro. "Shielding design calculation for SPring-8 beamlines using STAC8." Journal of Synchrotron Radiation 5, no. 3 (May 1, 1998): 615–17. http://dx.doi.org/10.1107/s0909049597019249.

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The beamlines of SPring-8 are classified by synchrotron radiation source into undulator, wiggler and bending-magnet beamlines for safety analysis. The shielding design calculations for synchrotron radiation are performed with a new shielding design code, STAC8, taking into consideration the linear-polarization effect, the slant length of the shield hutch wall and the build-up effect as functions of scattering angle and azimuthal angle.

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47

Lagunes-Espinoza, L. C., C. Huyghe, J. Papineau, and D. Pacault. "Effect of genotype and environment on pod wall proportion in white lupin: consequences to seed yield." Australian Journal of Agricultural Research 50, no. 4 (1999): 575. http://dx.doi.org/10.1071/a98151.

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One means of increasing seed yield in white lupin may be the modification of the harvest index in the reproductive compartment by a reduction of the proportion of pod walls. Genetic and environmental effects on the pod wall proportion and yield components were evaluated. Thirty-five genotypes of spring-sown material were sown in 6 different locations across France in 1996 and 1997, accounting for a total of 10 site × year combinations. The existence of a genetic variation for the pod wall proportion among studied genotypes was demonstrated (0.26–0.34). Highly significant genotypic differences for the pod wall proportion, seed number per pod, seed weight per pod, mean seed weight, flowering time, and seed yield were observed among lupin genotypes. The heritability of pod wall proportion was moderate, the phenotypic correlation between this character and seed yield was significant and negative, and the genetic correlation was high and negative. The environmental variance contributed a major part of the total variation. The genotype × environment effect for the pod wall proportion was small, which suggests that the selection of genotypes with low and stable pod wall proportion in different environments will be possible. The strong negative genetic correlation between pod wall proportion and seed yield supports the feasibility of using the character as a selection criterion for a higher seed yield.

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Wu, Yeming, Adam M. Vogel, Elizabeth A. Sailhamer, Stig Somme, Matthew J. Santore, Walter J. Chwals, Mindy B. Statter, and Donald C. Liu. "Primary Insertion of a Silastic Spring-Loaded Silo for Gastroschisis." American Surgeon 69, no. 12 (December 2003): 1083–86. http://dx.doi.org/10.1177/000313480306901212.

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Gastroschisis is traditionally managed by emergency primary closure, with a temporary silo reserved for large defects unable to be closed primarily. We recently have begun primary Silastic (Dow Corning, Midland, MI) spring-loaded silo (SLS) closure followed by elective closure and report our preliminary experience. A total of 15 infants (weight range, 2.1-13.5 kg) at 2 different institutions were treated by SC by 3 different surgeons between 1998 and 2002. A 3-, 4-, or 5-cm (ring diameter) silo was used depending on size of abdominal wall defect. Elective closure was performed in the operating room or at the bedside. Surgical parameters assessed included success of SLS, peak inspiratory pressures (PIPs) pre- and post-SLS closure, total time of staged closure with SLS, time to full feedings, and intra- and postoperative complications. Fifteen of 15 infants were successfully treated by SLS closure followed by elective closure. Two of 15 (13.3%) experienced temporary dislodgement of the silo prior to permanent closure. In both cases, the silo was safely reinserted at the bedside. Comparison of PIP values measured at various stages of SLS closure revealed no significant difference (P > 0.05). Mean times to final fascial closure (3.7 days) and full enteral feedings (22 days) were similar to historical controls obtained from the surgical literature. In 1 case where there was associated intestinal atresia, SLS closure was effective in permitting concomitant elective closure and re-establishment of bowel continuity. All children are alive and well at the time of this report. SLS closure permits safe, gentle, and gradual reduction of the exposed viscera leading to successful permanent abdominal wall closure. Respiratory embarrassment and hemodynamic instability associated with emergent (primary) closure of large abdominal wall defects can thus be avoided.

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Bozickovic, Aleksa, Goran Grubic, Nenad Djordjevic, and Bojan Stojanovic. "Changes in alfalfa cell wall structure during vegetation." Journal of Agricultural Sciences, Belgrade 59, no. 3 (2014): 275–86. http://dx.doi.org/10.2298/jas1403275b.

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The investigation was done on 141 samples of one alfalfa cultivar, collected from the same location during the first three growth cycles: spring growth, the first and the second regrowth. Within each growth cycle, sampling was done during the whole growing period, commencing when plant height was below 150 mm and continuing until plants were bearing ripe seeds. On all collected samples the following cell wall characteristics were determined: neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), neutral detergent insoluble crude protein (NDICP), acid detergent insoluble crude protein (ADICP). Cellulose and hemicellulose were detected on the base of the mentioned chemical parameters. Significantly lower (p<0.01) content of aNDF, ADF, ADL, ADICP and cellulose is found in the second regrowth, while there were no significant differences between the other two growth cycles. Except in NDICP and ADICP, the increase in all accompanying components of the cell wall was observed, and expressed in average daily changes. There was no consistent trend in NDICP and ADICP. During the spring growth from late bud to full-bloom stage the ?plateau? was observed. The plateau was represented as almost constant content of aNDF, ADF, ADL and cellulose. The correlations between all components of the cell wall were shown. The equation aNDF = 36.713 + 1.181 ? ADF is recommended for conversion of ADF into aNDF in alfalfa.

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Osanai, Shirou, Kiyonobu Nakaema, Akira Tanabe, Yosiaki Nakagawa, Motokane Kousaka, and Sinji Kaneda. "298. Development of wall attached type Lieder's Radiographic Stand (Using Conston Spring)." Japanese Journal of Radiological Technology 46, no. 8 (1990): 1270. http://dx.doi.org/10.6009/jjrt.kj00003322421.

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Journal articles on the topic 'Spring wall'

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