Blast traumatic brain injury (BTBI) is the major type of injury, existing helmets are mainly designed to resist bullets and fragments, so it necessary study explosion- proof performance helmets. In this study, validated finite element models including head, Advanced Combat Helmet (ACH), fully-covered helmet based on prototype Iron Man were used establish blast wave-helmet-head fluid–solid coupling model, dynamic responses such as wave flow field pressure, skull stress, tissue displacement...

Excellent prediction modeling of CO₂solubility in polymers using hybrid computation algorithm.

• A cranial model with human anatomy and mechanical properties was constructed. Comparative analysis of the impact type density lining materials on head protection performance. Two key indicators for evaluating brain injury, acceleration intracranial pressure characteristic parameters are analyzed. With upgrading protective equipment, penetration ability bullets into equipment is reduced, problem non-penetrating injury caused by bullet becomes prominent, but related experiment still rare....

Abstract Accurate recognition of aero-engine pipeline faults is great significance for engine maintenance costs and downtime. Pipeline signals have a strong periodic time series correlation under pump source pressure pulsation stimulation. However, very few studies considered the features at period points. Additionally, it challenging to realize intelligent fault diagnosis weak characteristics due influence vibration-noise coupling aero-engines. The information feature extraction model...

Abstract A four‐layer fuzzy neural network (FNN) model combining particle swarm optimization (PSO) algorithm and clustering method is proposed to predict the solubility of gases in polymers, hereafter called CPSO‐FNN, which combined theory's better adaptive ability, network's capability nonlinear PSO algorithm's global search ability. In this article, CPSO‐FNN has been employed investigate CO 2 polystyrene, N polypropylene, respectively. Results obtained work indicate that an effective for...

ABSTRACT A novel model based on a radial basis function neural network (RBF NN), chaos theory, self‐adaptive particle swarm optimization (PSO), and clustering method is proposed to predict the gas solubility in polymers; this hereafter called CSPSO‐C RBF NN. To develop NN, conventional PSO was modified with theory inertia weight factor overcome its premature convergence problem. The classical k ‐means used tune hidden centers spreads, algorithm optimize NN connection weights. Then,...

In order to reveal the dissolution process, adsorption kinetics and diffusion theory are combined used describe adsorption-diffusion mechanism. This can not only predict solubility of supercritical CO2 in polymer melts but also two important parameters process: amount rate, which provide a good theoretical basis for microcellular foaming. To verify feasibility accuracy calculation method, an experimental device volume-changing method under static condition was established. The results showed...

ABSTRACT In this study, the experiments of gas‐assisted extrusion (GAE) for molten polypropylene were carried out under different gas pressures, extrudate deformations and sharkskin defects melt observed. To ascertain effects on extrusion, non‐isothermal numerical simulation GAE based gas/melt two‐phase fluid model was proposed studied. simulations, extruded profile, physical field distributions (velocities, pressure drop, first normal stress difference) obtained. Numerical results showed...

The mechanism of Behind Helmet Blunt Trauma (BHBT) caused by a high-speed bullet is difficult to understand. At present, there still lack corresponding parameters and test methods evaluate this damage effectively. purpose the current study therefore investigate response human skull brain tissue under loading impacting bullet-proof helmet, with effects impact direction, speed, impactor structure being considered. A finite element model which can accurately reconstruct anatomical structures...

A solubility prediction model based on a hybrid artificial intelligence method integrated with diffusion theory is proposed.

Novel calculation model of CO₂solubility in polymers using a hybrid intelligence algorithm.

In this study, to better reflect the slip effect of Poiseuille flow for polymer melt extruded through a circular tube, novel unified wall model and equation based on two phase fluid system were proposed via purely phenomenological approach. According different combinations boundary conditions parameters, was transformed into other models, such as adsorption–desorption model, entanglement–disentanglement lubrication layer Z–W no‐slip model. The numerical simulation computed dynamics performed...

The diameter of a micro-tube is very small and its wall thickness thin. Thus, when applying double-layer gas-assisted extrusion technology to process micro-tube, it necessary find the suitable inlet gas pressure method for forming stable double layer. In this study, experiment conducted combined with numerical simulation made by POLYFLOW analyze effect on molding rheological properties melt under different pressures. A layer proposed, formation mechanism analyzed. research shows that large,...

Abstract Recently, there has been growing interest in water‐assisted injection molding (WAIM) not only for its advantages over gas‐assisted (GAIM) and conventional (CIM), but also great potential industrial applications. To understand the formation mechanism of water penetration induced fiber orientation overflow (OWAIM) parts short glass fiber‐reinforced polypropylene (SGF/PP), this work, external fields process within mold cavity were investigated by experiments numerical simulations. The...

Explosion overpressure propagates extracranially and causes craniocerebral injury after being transmitted into the brain. Studies on extent of skull to reduce impact are still lacking. Therefore, it is necessary study relationship between intracranial pressure (ICP) external field situation under blast wave. Pressure sensor ϕ 1.2 mm was disposed 3 posterior bregma rat skull, type I biological shock tube (BST-I) used as source while a side-on air installed at horizontal position ICP sensor....