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Background: Children's moral development is influenced by their sociocultural context. However, relatively few studies have investigated whether the sociocultural context affects children's lying behavior and cognition and the relation between them. Methods: The present study was designed to examine this question in two experiments by posing two moral dilemmas: lying is good for mutually beneficial (honesty conflicts with mutual interests) and lying is good for self-beneficial (honesty conflicts with self-interests). Experiment 1 used the "hide-and-seek" game to investigate the lying behavior of 96 Chinese 4- to 5-year-old children. Experiment 2 used two videos to investigate lying cognition (conceptualization of lying, moral assessment of lying, and prediction of lying) with the same group of children. Results: In Experiment 1, children lied more in mutually beneficial situations than in self-beneficial situations. Experiment 2 revealed that, compared with self-beneficial situations, children in mutually beneficial situations were more likely to judge untrue statements as truth, to evaluate lying positively, and to predict that they would lie. Further, in mutually beneficial situations, children's predicted and actual lying behaviors are significantly positively correlated. Conclusion: These findings support the folk model and highlight the influence of sociocultural factors on lying in Chinese 4- to 5-year-old children. They offer meaningful insights into the development of early moral understanding and behavior. [ABSTRACT FROM AUTHOR]

This paper presents that the prediction model of fatigue crack initiation life of TC4 titanium alloy,and the feasibility of the model in predicting the fatigue crack initiation life of TC4 titanium alloy is verified by experiments. Based on the micro dislocation model of crack initiation and Tanaka mura’s formula of crack life,considering the surface roughness,a finite element model for fatigue crack initiation of TC4 titanium alloy is proposed,and the validity of the simulation model is verified by experiments. The results show that the crack initiation forms of the model are different under different load levels. At high stress levels,the model has a large number of independent microcracks in addition to the initiation and propagation of the main cracks,with a large crack density. At low stress levels,the model has a small number of independent microcracks,with a small crack density.

A hierarchical coupled multiscale method is developed to capture the onset and propagation of damage within the three-dimensional four-directional (3D4D) braided composites subjected to bending loading. Using a directly two-scale coupled scheme, the macroscopic nonlinear behavior at the structural dangerous region could be iteratively solved, combined with the progressive damage response of the realistic mesoscale architecture. The continuum damage model is merely defined at the mesoscale and considers failure in each of constituents with the well-established Hashin failure criteria and the Bažant crack band damage model. To accelerate finite element computation in two scales, a parallel numerical implementation is presented alongside the commercial software ABAQUS/Standard. Besides the good agreement between the experimental and the predicted values, the results also show a significant effect of the braiding angle on the bending performance of 3D4D braided composites. With the increase of braiding angle, the bending stiffness and strength of 3D4D braided composites decreases, but the fracture toughness increases. This phenomenon was numerically investigated by identifying the different fundamental failure mechanism and damage development process at both the scales. [ABSTRACT FROM AUTHOR]

Stitched composite material not only suppresses delamination expansion, but also improves inter-laminar toughness and compressive characteristics after impact by introducing stitch in the thickness direction. Equivalent hole method simulates the initial damage of stitched plate. The finite element analysis method with damage evolution process based on threedimensional Hashin criterion with 3D solid element modelling laminates,3D bar element modelling stitch simulated the stitched composite laminates damage evolution effectively. The calculation results were in good agreement with the experimental data.

This article presents an experiment and simulation study on the effect of Z-pin reinforced on the pull-off and sheat carrying capacity of fiber placement composite T-joints,we used CMT5504 to conduct the pull-off test meanwhile we used MTS to conduct the shear test. we studied Z-pin reinforced And non-reinforced test-pieces,drawing Load-displacement curves.The pull-off test results donate that Z-pin can effectively improved the pull-off carrying capacity of T-joints and slow the decrease of the load significantly after pick loading compared to the non-reinforced T-joints. The failure location is between stiffener and interlayer. The shear test results donate that Z-pin can effectively improve the shear carrying capacity of T-joints. The failure location of Z-pin reinforced test is between skin and interlayer and the failure location of non-reinforced test is bwtween stiffener and interlayer. On this basis,we created pull-off and shear model of T-joint specimens. The interface failure was simulated with cohesive zone model,and the effect of Z-pin was simulated with nonlinear springs inserted into the interface. The numerical results agree well with the test data and shows that the model is effective.

A 3D model of composite laminates with bolted joint is created by using the software ABAQUS. By introducing the 3D Hashin failure criteria and considering the tightening torque,the partition and the global degradation models were established. With this method,the failure process and the linking strength of single-lap,single-bolt joints were calculated. The results shows that the load-displacement curve by using global degradation model doesn’t degrade enough and the computing results are more accurate by using the partition degradation model. With the increase of thickness,the linking strength of bolted single-lap composite joints decrease all the time and the speed of degradation gets slower and slower. It means that with the increase of thickness,the lifting bearing capacity of structure reduces. It also indicates that the ultimate strength of laminate is enhanced with appropriate tightening torque and excessive tightening torque impairs the load carrying capacity of the structure.

This paper deals with the optimization of multi-laminate structures by Multi-Island Genetic Algorithm (MIGA) coupled with CAE solver. The optimization problem is a compound problem which relates to size optimization for object structure and stacking sequence optimization for variable-thickness composite laminates. Taking a typical adhesive bonded sandwich T-joint under a reference pull-off load as an instance object and establishing strength conditions on the basis of progressive damage analysis, optimum design is carried out with the total weight of joint as the target function. Progressive damage model (PDM) methodology and cohesive zone model (CZM) methodology are employed to develop an exact finite element model of the object structure. Classified failure criteria are chosen to investigate the capability of the joint in bearing the applied load. The optimization procedure on the typical adhesive bonded sandwich T-joint showed 34.24% weight reduction compared to the initial laminated structure. On the basis of history data, the study further brings out the influence of design variables on some main constraint variables. [ABSTRACT FROM AUTHOR]

AbstractThree-dimensional orthogonal woven composites (3DOWCs) offer significant advantages in engineering applications due to their designability for spatial structures and ability to minimize delamination damage. As primary load-bearing structures, 3DOWCs are always in preloading conditions prior to potential low-velocity impact (LVI) events. This paper presents a macro-meso coupled finite element (FE) model for investigating the response of preloaded 3DOWCs subjected to LVI. The accuracy of the proposed numerical model is validated by a comparison with available experimental data in terms of impact performance and damage state. Furthermore, the influence of preload and impactor shape on the LVI performance of 3DOWCs is examined, and detailed analysis is provided regarding the associated damage mechanisms. This study offers a transferable numerical approach that can be applied to studying the coupling problems of LVI and preload in other textile composite structures. [ABSTRACT FROM AUTHOR]