A 6 years old girl accidentally aspirated a plastic whistle while playing. Computed Tomography of thorax showed foreign body at carina level. Rigid bronchoscope under general anesthesia was attempted but unable to extract the whistle through vocal cord. Tracheostomy was later performed and foreign body was removed.

According to the auditory principle of fish’s lateral line organ, a novel microelectromechanical systems (MEMS) bionic vector hydrophone used for obtaining vector information of underwater sound field is introduced in this paper. It is desirable that the application of MEMS-based piezoresistive effect and bionics structure may improve the low-frequency sensitivity of the vector hydrophone as we...

A bar-slider framework is a bar-joint framework a part of whose joints are constrained by using line-sliders. Such joints are allowed to move only along the sliders. Streinu and Theran proposed a combinatorial characterization of the infinitesimal rigidity of generic bar-slider frameworks in two dimensional space. In this paper we propose a generalization of their result. In particular, we prov...

A study of four constitutive contact models employed in discrete element analysis is presented. Most discrete element simulations employ simple contact models due to computational time constraints. However, few works are available in literature which evaluates the suitability of these simple models to simulate DEM applications. The influence of more complex models on bulk behavior is examined t...

A rigid-plastic Cosserat model has been used to study dense, fully developed flow of granular materials through a vertical channel. Frictional models based on the classical continuum do not predict the occurrence of shear layers, at variance with experimental observations. This feature has been attributed to the absence of a material length scale in their constitutive equations. The present mod...

In some circumstances, elastic-plastic deformation occurs in which both components of strain are finite. Such situations fall outside the scope of classical plasticity theory which assumes either infinitesimal strains or plastic-rigid theory for large strains. The present theory modifies the kinematics to include finite elastic and plastic strain components. For situations requiring this genera...

the development of yielded or failure zone due to an engineering construction is a subject of study in different disciplines. in petroleum engineering, depletion from and injection of gas into a porous rock can cause development of a yield zone around the reservoir. studying this phenomenon requires elasto-plastic analysis of geomaterial, in this case the porous rocks. in this study, which is a...

Contact between a slider and a magnetic recording disk is modeled as transient contact of a sphere on a moving flat. The sphere is assumed to be rigid, and the flat is treated as an elastic-plastic body with isotropic hardening. Heat generation is related to friction at the contact interface. Dimensionless solutions are obtained for maximum temperature rise, maximum contact force, maximum conta...

A constitutive multi-laminate based elastic-plastic model developed to be capable of accounting induced anisotropic behavior of granular material such as sand. The fabric feature or grain orientation characteristic effects through medium are considered in a rational way under any complex stress path, including cyclic loading. The salient feature of the developed model is a non-associative on pl...

Abstract The local structure of the cylindrical shell produces plastic deformation under near-field underwater explosion load, based on fact that ring rib is strong support reinforced plate, this paper simplifies model into a rigid slatted beam at both ends, and lists equations beams action shock wave bubble pulsation load. This equation takes initial damage caused by account, compares calculat...