Numerical Advances in Gross-Motion Simulations of Head/Neck Dynamics

1987 ◽  
Vol 109 (2) ◽  
pp. 163-168 ◽  
Author(s):  
C. S. Tien ◽  
R. L. Huston
Keyword(s):  
Experimental Data ◽  
Efficient Method ◽  
Whole Body ◽  
Motion Simulation ◽  
Finite Segment ◽  
Body Model ◽  
High Acceleration ◽  
Head Neck

An efficient method for gross-motion simulation of head/neck dynamics in accidents and high acceleration environments is presented. The method uses finite-segment modelling to develop a 3-body model of the head/neck system. The model is shown to compare favorably with an analogous 9-body model and with experimental data. The model is expected to be useful for: (1) efficient analysis of gross-motion head/neck dynamics during accidents; (2) for developing increased intuitive understanding of head/neck behavior; and (3) for use with gross-motion, whole-body, crash-victim simulators.

Multi-Objective Optimization of Human Gait With a Discomfort Function

2016 ◽  
Author(s):  
Hyun-Jung Kwon ◽  
Hyun-Joon Chung ◽  
Yujiang Xiang
Keyword(s):  
Joint Torque ◽  
Upper Body ◽  
Whole Body ◽  
Human Gait ◽  
Multi Objective Optimization ◽  
Joint Angles ◽  
Backward Walking ◽  
Multi Objective ◽  
Body Model ◽  
Neutral Angle

The objective of this study was to develop a discomfort function for including a high DOF upper body model during walking. A multi-objective optimization (MOO) method was formulated by minimizing dynamic effort and the discomfort function simultaneously. The discomfort function is defined as the sum of the squares of deviation of joint angles from their neutral angle positions. The dynamic effort is the sum of the joint torque squared. To investigate the efficacy of the proposed MOO method, backward walking simulation was conducted. By minimizing both dynamic effort and the discomfort function, a 3D whole body model with a high DOF upper body for walking was demonstrated successfully.

scholarly journals Multi-task Bayesian Optimization of Chemical Reactions

2020 ◽  
Author(s):  
Kobi Felton ◽  
Daniel Wigh ◽  
Alexei Lapkin
Keyword(s):  
Experimental Data ◽  
Recent Work ◽  
Chemical Reactions ◽  
Efficient Method ◽  
In Silico ◽  
Bayesian Optimization ◽  
Reaction Optimization ◽  
Similar Chemical

Recent work has shown how Bayesian optimization (BO) is an efficient method for optimizing expensive experiments such as chemical reactions. However, in previous studies, each optimization has been started from scratch with no information about previous or similar chemical optimization studies. Therefore, BO can still require more iterations than many experimental budgets provide. Here, we overcome this challenge using multi-task BO. Through<i> in silico</i> benchmarking studies, we show how past experimental data can be leveraged to improve the quality and speed of reaction optimization.

scholarly journals Evaluation of Health Risk Level of Hand-Arm and Whole-Body Vibrations on the Technical Operators and Equipment in a Tobacco-Producing Company in Nigeria

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Oluseyi Adewale Orelaja ◽  
Xingsong Wang ◽  
Dauda Sh. Ibrahim ◽  
Umer Sharif
Keyword(s):  
Whole Body ◽  
Risk Level ◽  
Time Frequency ◽  
Daily Exposure ◽  
Limit Value ◽  
Exposure Limit ◽  
High Acceleration ◽  
External Forces ◽  
Secondary Manufacturing ◽  
Iso 2631

Vibration is experienced when a body is subjected to either internal or external forces which cause oscillation, with most operators of industrial equipment often exposed to high dosage, higher than the stipulated values. In this research, Digital Real-Time Frequency Analyzer (RSA 5106A) was used, while the results obtained were evaluated and compared with the health guidelines of the ISO 2631-1 : 1997 and ISO 2631-5 : 2004 standards, as described in the Health Guidance Caution Zone for a daily exposure action value (EAV) of 0.47 m/s2 and a daily exposure limit value (ELV) of 0.93 m/s. High acceleration was mostly seen on the z-axis in all the results obtained, whereas many were not within the HGCZ (Arms <0.47, and >0.93 m/s2). Comparing (VDV <8.5 m/s1.75 and >17 m/s1.75) with the ISO standard, the accelerations on all x- and y-axes were slightly within the HGCZ, with just a little below 0.47 m/s2 limit. The results obtained clearly showed that urgent action is needed virtually on all the equipment in both the Secondary Manufacturing Department (SMD) and Primary Manufacturing Department (PMD) to minimize vibration exposure on the technical operators.

Modeling of Human Reactions to Whole-Body Vibration

1987 ◽  
Vol 109 (3) ◽  
pp. 210-217 ◽  
Author(s):  
Farid M. L. Amirouche
Keyword(s):  
Human Body ◽  
Equations Of Motion ◽  
Vertical Direction ◽  
The Body ◽  
Whole Body ◽  
Connective Tissues ◽  
Finite Segment ◽  
Body Vibration ◽  
Forcing Function ◽  
Impulse Function

A computer-automated approach for studying the human body vibration is presented. This includes vertical, horizontal, and torsional vibration. The procedure used is based on Finite Segment Modeling (FSM) of the human body, thus treating it as a mechanical structure. Kane’s equations as developed by Huston et al. are used to formulate the governing equations of motion. The connective tissues are modeled by springs and dampers. In addition, the paper presents the transient response of different parts of the body due to a sinusoidal forcing function as well as an impulse function applied to the lower torso in the vertical direction.

scholarly journals Optimization of Female Head–Neck Model with Active Reflexive Cervical Muscles in Low Severity Rear Impact Collisions

2020 ◽  
Vol 49 (1) ◽  
pp. 115-128
Author(s):  
I Putu A. Putra ◽  
Johan Iraeus ◽  
Fusako Sato ◽  
Mats Y. Svensson ◽  
Astrid Linder ◽  
...  
Keyword(s):  
Human Body ◽  
Neck Muscle ◽  
Female Size ◽  
Human Body Model ◽  
Active Muscle ◽  
Body Model ◽  
Cervical Muscles ◽  
Muscle Reflex ◽  
Reflex System ◽  
Head Neck

AbstractViVA Open Human Body Model (HBM) is an open-source human body model that was developed to fill the gap of currently available models that lacked the average female size. In this study, the head–neck model of ViVA OpenHBM was further developed by adding active muscle controllers for the cervical muscles to represent the human neck muscle reflex system as studies have shown that cervical muscles influence head–neck kinematics during impacts. The muscle controller was calibrated by conducting optimization-based parameter identification of published-volunteer data. The effects of different calibration objectives to head–neck kinematics were analyzed and compared. In general, a model with active neck muscles improved the head–neck kinematics agreement with volunteer responses. The current study highlights the importance of including active muscle response to mimic the volunteer’s kinematics. A simple PD controller has found to be able to represent the behavior of the neck muscle reflex system. The optimum gains that defined the muscle controllers in the present study were able to be identified using optimizations. The present study provides a basis for describing an active muscle controller that can be used in future studies to investigate whiplash injuries in rear impacts

scholarly journals A whole body model of FDG metabolism based on VHP datasets

2008 ◽  
Vol 41 (2) ◽  
pp. 6664-6668
Author(s):  
Jing Bai ◽  
Huiting Qiao
Keyword(s):  
Whole Body ◽  
Body Model ◽  
Whole Body Model
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