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Relating Linear And Rotational Accelerations With Internal Pressures Developed Inside Human Head Surrogate Models, Arthur Thomas Koster

Mechanical and Aerospace Engineering Theses

Traumatic Brain Injury (TBI) is a chronic disease process that is difficult to both detect and treat. TBI can result from blast, kinetic, sonic, and electromagnet energy sources. This research focuses on correlating the bulk acceleration of a human-like head model to the localized internal pressure developed in the coup and contrecoup regions due to variable impact loading. Damage resulting in a TBI occurs on a multiscale level from the macroscale down to the damage of each individual neuron. Obtaining a relationship between bulk acceleration and localized internal pressure will allow for further correlation to the damage done on these …

A Nocsae Drop Test/ 3d-Fem Study On The Relationship Between Kinematic Response Of The Head, Head Impact Contact Pressure (Hicp) And Kinetic Response Of The Brain To Delineate The Risk Of Traumatic Brain Injuries (Tbi)., Raghavendra Krishna Tej Bhamidipati

Dissertations, Master's Theses and Master's Reports

How many times have you seen a person slip and fall down and had a good laugh about it? How many times we slip and fall down on the floor and got up and walked away thinking everything is normal? Probably we might wonder “Are drops which occur at a small height dangerous?” Yes, they can be. Brain injuries are main reason for the fatality in youth [1], and low level falls are one of the most neglected and understated injuries.

The main objective of this study is to study the response of the brain for low level falls from …

Tbi Induced Rate Dependent Viscoelastic Response Of Axon: Predictions From A Mathematical Model, Manikanta Jonnalagadda

Mechanical and Aerospace Engineering Theses

Traumatic brain injury (TBI) accounts to almost one fifth of total fatal injuries. Even though there are various mechanisms hypothesized for the causes leading to TBI, diffuse axonal injury (DAI) is found to be the most observed criterion. The reason for axonal failure in DAI has been studied extensively using experimental and computational models. It was found that axons behave like viscoelastic materials, thus exhibiting rate dependent behavior under loading. This viscoelastic behavior of axons is believed to drive the failure of axons and its substructures. It was observed that axon failure is caused by failures and distortions in axonal …

Morphology Of Brain Sulci Trabeculae And Its Effect On Brain During Impacts, Sharlin Anwar

Dissertations and Theses

Traumatic brain injury (TBI) is an intracranial injury caused by direct contact or non-contact head impacts to the brain. TBI is a major problem that accounts for high incidents of hospitalizations each year. Thus, it is important to understand and predict the occurrence of TBI in an impact. It has been shown that the subarachnoid space (SAS) trabeculae play an important role in damping the effect of an impact, thus reducing the injuries. However, the influence of sulci parameters and the sulci trabeculae in TBI due to impact is unexplored. Studies have shown that inclusion of sulci in brain models …

Design And Analysis Of Blast Induced Traumatic Brain Injury Mechanism Using A Surrogate Headform: Instrumentation And Outcomes, Eyitejumade A. Sogbesan

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Brain injury cases in military personnel exposed to improvised explosive devices (IED) in combat have been on the rise. In Iraq and Afghanistan improved helmets and body armor are not enough protection against blast wave threats. The United States military are sponsoring researchers and scientists around the globe to find the associations between pressure waves and traumatic brain injury (TBI).

Lack of accurate data and blast wave exposure information in returning soldiers has slowed the innovation needed to effectively diagnose TBI and other related brain injury as a result of pressure waves. More detailed data will be required to gain …

A Shock Tube Technique For Blast Wave Simulation And Studies Of Flow Structure Interactions In Shock Tube Blast Experiments, Nicholas N. Kleinschmit

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Improvised explosive devices (IED’s) are widely used against US and allied forces fighting in Iraq and Afghanistan. Exposure to IED blast may cause blast-induced traumatic brain injury (bTBI). The injury mechanisms are however not well understood. A critical need in bTBI-related research is the ability to replicate the loading conditions of IED blast waves in a laboratory environment. In this work, experimental studies have been carried out to explore the use of the shock tube technique for generating air shock waves that mimic the temporal and spatial characteristics of free-field blast waves and to investigate the blast wave-test sample interactions …

Role Of Helmet In The Mechanics Of Shock Wave Propagation Under Blast Loading Conditions, Shailesh G. Ganpule, Linxia Gu, Aaron L. Alai, Namas Chandra

Department of Mechanical and Materials Engineering: Faculty Publications

The effectiveness of helmets in extenuating the primary shock waves generated by the explosions of improvised explosive devices is not clearly understood. In this work, the role of helmet on the overpressurization and impulse experienced by the head were examined. The shock wave–head interactions were studied under three different cases: (i) unprotected head, (ii) head with helmet but with varying head–helmet gaps and (iii) head covered with helmet and tightly fitting foam pads. The intensification effect was discussed by examining the shock wave flow pattern and verified with experiments. A helmet with a better protection against shock wave is suggested.