Evaluating the biofidelity of spinal response in ATDs and computational models requires additional benchmarking data. The current study presents a kinematic analysis methodology for obtaining intrasegmental kinematics of the spine including elongation, compression, displacement, and anatomical rotations of the spine including flexion, lateral flexion, and rotation. The presented methodology divides the spine into five spine segments selected for detailed kinematic analysis which were specifically the following: head-to-T1, T1-to-T8, T8-to-L2, L2-to-L4, and L4-to-pelvis. The methodology provides a technique to more comprehensively describe the kinematics of the whole human spine than has been performed to date in the impact environment.
In this study, a phenomenological combustion model, which had been developed based on a stochastic combustion model for simulating combustion with multi-stage injection in diesel engines, was improved to estimate the NOx and soot emissions with modifications in the model for the interaction of sprays from sequent injection stages. Model validation was performed by comparison with experimental data from a single-cylinder diesel engine. To understand the variation of NOx and soot production with injection conditions, analysis of combustion process was conducted based on the calculation results from different injection parameters including injection timing and quantity.
Ribcage geometry of 327 boys and girls (aged 1-18) was extracted from CT scans, consisting of three dimensional curves fit through the centroidal path of 6306 individual ribs. Each rib was characterized by 7 parameters describing a rib's in-plane geometry, 2 describing its out-of-plane deviation, and 3 describing the rib orientation relative to anatomical planes. Parameters were predicted by age and gender to fully describe variation in size and shape of rib centroidal geometry as a continuous function following growth throughout childhood. A demographics-based model was also presented describing average ribcage geometry for children of any given age, weight, and height.
Global Navigation Satellite Systems (GNSSs) suffers from multipath effect in urban canyons. Many approaches have been employed to eliminate multipath signals in order to reduce positioning errors. Among these, ideas that consider surrounding buildings to evaluate possible multipath have gained most interest. However, such approaches, although successful, require many satellites after eliminating multipath signals. This study proposes an approach in which the multipaths themselves are used for positioning error correction. The proposed algorithm evaluates the pseudoranges of the possible multipath signals by referring to the building geometry. The proposed method was verified through field experiments in urban canyons in Tokyo.
Relative brain-skull displacement under head rotational acceleration in rats was evaluated experimentally. For this, a thin pin was entered the cortex and rigidly attached to the skull prior to impact. For peak rotational accelerations of 1.7 Mrad/s2, the pin scarred the brain cortex; 1.2 mm superficially and less centrally. These measurements were used to validate the brain kinematics of a new anatomically detailed FE model of the head-neck complex of a rat. This model is intended to be used to clarify brain loading mechanisms and to develop brain tissue injury threshold for Diffuse Axonal Injuries as detected through immune-histology.
In the course of developing an alternative test condition to explore torso response, the NHTSA’s THOR Mod Kit Dummy was evaluated in two simulated frontal impact conditions. The recently proposed condition, which is less severe, produced less shoulder belt tension resulting in lower chest deflection. It also produced differences in the pattern of anterior ribcage deflection. The results of this study suggest that this less severe frontal impact test condition will produce sufficiently different PMHS response relative to that recorded in previous PMHS tests, including fewer rib fractures as well as an altered pattern of anterior ribcage loading.