bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validation of a Non-Linear Finite Element Vehicle Model Using Multiple Impact Data
Authors: Zaouk Abdullatif K. , Bedewi Nabih E. , Kan Cing-Dao , Marzougui Dhafer 
Published: July 2023

Abstract
A detailed multi-purpose finite element model of a 1994 Chevrolet C-1500 pick-up truck was developed at the FHWA/NHTSA National Crash Analysis Center. The model is the first of its kind developed specifically to address vehicle safety issues, including front and side performance, as well as road side hardware design. The former application typically involves large regional deformation with impact durations of no more than 150 msec. The latter encompasses damage along a larger portion of the vehicle, and due to longer interaction time between the vehicle and impacted device coupled with the need to observe post impact dynamics, requires simulations that could last as long as 1 second.
This paper describes the results of a non-linear finite element computer simulation using this model for frontal full barrier and median highway barrier impacts. These simulations are conducted in support of research studies undergoing at the National Highway Traffic Safety Administration (NHTSA) and the Federal Highway Administration (FHWA) to investigate vehicle compatibility, new offset barrier tests, and highway/vehicle safety issues. Full scale vehicle crash tests conducted by NHTSA and FHWA are used for evaluation of the performance of the model. Two tests are compared, a frontal impact with a full rigid wall and a corner impact to a 42-inch Vertical Concrete Median. The comparisons between tests and simulations in terms of overall impact deformation, component failure modes, velocity and acceleration at various locations in the vehicle are presented. Modeling issues including element size, connectivity, and slide line interface of different parts are discussed. In addition, some simulation related hardware and software issues are addressed. The results clearly indicate the model to be consistent with the full scale tests. Additional simulations need to be performed to fully evaluate and validate the model.
Non-Steady-State Gas Dynamical Process of a Laser Supported Wave Formation in Free Gas Flow
Authors: Surzhikov Sergey T. 
Published: July 2023

Abstract
A non-steady-state problem concerning subsonic stage of low-temperature plasma jet formation in laser supported waves in air of atmospheric pressure is considered. The low-temperature plasma is sustained by CW CO2 laser radiation focusing near a surface through which an air of atmospheric pressure is blowing.
Two-dimensional radiative-gasdynamical model is presented. The model consists of Navier-Stokes equations, conservation energy equation, selective radiative heat transfer equation and CO2-laser radiation transfer equation. The real temperature dependence of air thermophysical and optical properties are taken into account.
Numerical results of computational simulation of the phenomena are presented. A numerical solution with vortex gas dynamical structure inside laser supported plasma is obtained.
The Dynamics of Particle Formation During SiH4:O2 Chemical Vapor Deposition: Implications for Materials Processing
Authors: Whitby Evan , Hoshino Masakazu , Ikegawa Masato 
Published: July 2023

Abstract
Particle size distributions were measured at a height 2 cm above a heated wafer in a chemical vapor deposition reactor, in the pressure range, P, of 650 &lt; P &lt; 3250 Pa, and compared with size distributions calculated with a two-dimensional numerical model that simulates fluid flow, heat transfer, chemical reactions, and particle formation, transport, and deposition. Both the measurements and the numerical simulations show that the particle number concentration at a height of 2 cm is proportional to P9 in the pressure range of 650 &lt; P &lt; 1950 Pa. A key result from this work is that at low pressures, cluster sticking coefficients strongly control the rate of cluster formation, and therefore the rate of particle formation.
A Numerical and Experimental Investigation of Morphology Development in Straight and Folded Molten Fibers During Melt Processing
Authors: Zhang D. F. , Liu Y. H. , Zumbrunnen D. A. 
Published: July 2023

Abstract
The morphological evolution of straight and folded molten fibers in shear flows was investigated systematically. Folded fibers were of interest since folding may occur during melt processing and since folded fibers resemble portions of more complex extended structures in melts subjected to chaotic mixing conditions. Shear flows represent local flow conditions within actual mixing cavities, continuous mixers, and extruders. A general three-dimensional numerical model of the time-dependent fluid flows within the minor phase (i.e., fiber) and major phase (i.e., the matrix) was developed. Interactions between the minor and major phase fluids via fully dynamical, three-dimensional interfaces were considered. The relation of morphological changes to the fibers, including break up, were disclosed. Numerical results were supplemented with micrographs of solidified polymeric fibers and sheets produced within a recently developed mixing cavity where mixing occurred due to chaotic advection.
Finite Element Analysis of the Advanced Photo System Bubble Spring Head/Film Interface
Authors: Haugh Donald J. , Brewen Alan T. 
Published: July 2023

Abstract
This paper describes the finite element model used to predict the spacing and contact pressure in an Advanced Photo System head/film interface. The particular interface analyzed was developed for use in photofinishing applications and is commonly referred to as a bubble spring interface, named after the flexure-like thin metal strip used to push the film against the magnetic head. The model results are validated by comparing predictions to measurements of the spring load-deflection profile and interferometrically measured head-to-film spacing contours. In addition, the model’s capability is demonstrated by using it to assess performance sensitivity to variations in spring load, head/film penetration, and film curl.
Experimental Characterization of Air Entrainment During High Speed Web Winding
Authors: Keshavan M. B. , Wickert J. A. 
Published: July 2023

Abstract
As a web is wound at speed onto a spool or roll, a thin layer of air becomes entrapped between the incoming web stream and the roll. The spiral-shaped air bearing which results separates adjacent web layers and can extend many wraps into the roll. The air entrained during the winding process increases the propensity for interlayer slippage, stack shifting, damage to the edges of the web, and non-uniform internal stresses. A new technique is discussed for measuring the film thickness of the entrained air layers during the winding process, and parameter studies quantify the effects of such winding variables as tension, transport speed, and surface roughness. With a view towards evaluating different web transport designs and operating conditions, three measures of air entrainment are discussed: (i) the cumulative thickness of all air layers, (ii) the thickness of the outermost air layer at the nip, and (iii) the rate at which air bleeds from the wound roll once it is brought to rest.
Control System Design for High-Speed Low-Tension Tape Transport
Authors: Mathur Priyadarshee D. , Messner William C. 
Published: July 2023

Abstract
This paper describes the entire process of control system design for a prototype high-speed, low-tension tape transport system. The speed and tension of the tape are regulated by controlling the relative displacement of the supply and take-up reels. The system is slowly time varying from changing reel packs, and is difficult to model because the spring constant of the tape depends on the operating speed and tension due to air entrainment in the take-up reel. In this paper, an iterative multi-input multi-output controller design approach is presented where a low performance controller is first designed to enable system identification around the desired operating speed and tension of the transport. The frequency response data is then used to design a fast settling controller. An adaptive ripple cancellation scheme for better tension regulation is demonstrated. Failure detection mechanisms and recovery algorithms that reduce the probability of tape damage are described.
Shock Fragility of Spindle Motors in Hard Drives
Authors: Salehizadeh Hamid 
Published: July 2023

Abstract
The susceptibility of spindle motor ball bearings in disk drives to axial shock is considered in this paper. When a hard drive is subjected to an axial shock, the spindle disk pack is excited axially and the ensuing vibrations lead to dynamic forces. Should the maximum force endured by the bearings exceed their rated carrying capacity, permanent bearing damage will take place at the ball/race interface which manifests itself in higher vibration and acoustic levels.
To estimate the dynamic bearing force and the shock fragility of a given drive, it is imperative to solve for the vibration of the drive when subjected to shock. This was achieved in the present work by simplifying the dynamics of a hard drive to that of a two degree of freedom mass-spring system. The equivalent mass and stiffness values were obtained by matching the modal frequencies of the 2 DOF model to those of the disk pack. The response of the model to axial shock was next obtained by numerical integration using the Runge-Kutta method. The non-linear bearing stiffness was incorporated using the Hertzian equations in the model. To validate the model, the response of a hard drive to axial shock was measured using an accelerometer mounted on the motor hub. Excellent agreement was obtained between calculated response and experimentally measured motor hub vibration. Having verified the model, the calculated maximum bearing force was used to estimate the drive’s shock threshold. It was found that base casting stiffness and damping play an important role in the dynamic amplification of the bearing force.
A System for Image Guided Computer Assisted Hip Surgery
Authors: Langlotz Frank , Stucki Manfred , Nolte Lutz P. , Gong Jianxing 
Published: July 2023

Abstract
The term periacetabular osteotomy (PAO) refers to a surgical intervention that attempts to correct dysplasia of the hip joint, particularly malposition of the acetabular roof which causes insufficient coverage of the femoral head. The procedure, as performed in Bern, consists of several osteotomies of the pubis, ischium, and ilium and a re-orientation of the acetabular fragment with subsequent fixation. Various solutions exist for a preoperative determination of the optimal re-orientation of the acetabular cup (Barrance et al., 1995, Klaue et al., 1988, Murphy et al., 1990). However, it has not been possible to apply the planning parameters accurately during the operation. In addition, some of the osteotomies have to be performed without direct visual access to the surgical object due to limitations in the anatomy and exposure. Consequently, there is potential to endanger the hip joint and surrounding structures. It is hypothesized that a combination of accurate 3D-motion tracking together with image interactive navigation may establish a link between surgical planning and execution. To our knowledge, this study introduces for the first time an operation-system for PAO that bridges surgical planning, secure intraoperative navigation during the osteotomies, and exact guidance during the re-orientation in accordance with a preoperative planning.
Transient Cavitation and Associated Shock Wave Generation Near a Stone Surface During Electrohydraulic Lithotripsy
Authors: Tong H. L. , Zhong P. , Cocks F. H. , Preminger G. M. 
Published: July 2023

Abstract
Electrohydraulic lithotripsy (EHL), utilizing spark-induced shock waves for stone comminution, is a common treatment modality for kidney and ureteral stones1–2. During EHL, a spark discharge at the tip of a small probe introduced endoscopically produces a vapor plasma and subsequently a cavitation bubble near the stone surface. Although it is believed that shock waves are generated by the expansion of the vapor plasma and the collapse of the cavitation bubble, the dynamics of this physical process has not been well understood3. In this study, hiqh-speed photography and acoustic measurement were used to characterize the transient cavitation bubble oscillation and associated shock wave generation during EHL.
Effects of Tissue Mimicking Material on Transient Cavitation Produced During Extracorporeal Shock Wave Lithotripsy
Authors: Cioanta I. , Zhong P. , Cocks F. H. , Preminger G. M. 
Published: July 2023

Abstract
Extracorporeal shock wave lithotripsy (ESWL) is a widely used treatment modality for kidney and ureteral stones1. Recent studies have shown that transient cavitation induced by the tensile components of the lithotripsy shock waves is a primary mechanism for both stone fragmentation and tissue injury2. Thus, the ability to detect and monitor the cavitation activity during ESWL is important to ensure the effectiveness and the safety of the treatment. In this study, we have used acoustic emission measurement and high-speed photography to assess the transient cavitation generated during ESWL. The effects of tissue mimicking material on ESWL-induced cavitation activity was examined.
Validation and Accuracy Assessment of the Micropipet Piconewton Force Transducer
Authors: Chesla Scott E. , Zhu Cheng 
Published: July 2023

Abstract
In processes that involve interactions of the cell with its environment, adhesion is often the initiating event for a particular cellular function. Adhesion assays are thus among the first to be used to characterize the essential molecular complexes involved. Recently, increasing attention has been focused on single molecular binding between a particular cellular receptor class and its ligand. Elucidation of the forces involved in single bonds can lead to better understanding of how cells deal with their environment via controlling the specificity and strength of their adhesions.
Finite Element Analysis of Pulsatile Flow in the Abdominal Aorta Under Resting and Exercise Conditions
Authors: Taylor Charles A. , Hughes Thomas J. R. , Zarins Christopher K. 
Published: July 2023

Abstract
It is hypothesized that the beneficial effect of exercise in retarding the progression of cardiovascular disease is due, at least in part, to the elimination of adverse hemodynamic conditions including high particle residence time and low wall shear stress [1]. In-vitro and in-vivo investigations have provided limited qualitative information on flow patterns in the abdominal aorta and the effect of exercise on eliminating adverse hemodynamic conditions [2]. A computer model of a normal human abdominal aorta was created to simulate aortic blood flow under rest and graded exercise, pulsatile, flow conditions. Flow patterns, wall shear stress and particle residence time were computed in the lesion-prone infrarenal aorta and the effect of exercise determined.
A Mathematical Model of Nonlinear Viscoelastic Materials
Authors: Song Gong , Todd Beth A. 
Published: July 2023

Abstract
A mathematical model has been developed for nonlinear viscoelastic material under constant one dimensional stress. The mathematical proof is given that the creep and recovery function of nonlinear viscoelastic material can be expressed as the infinite sum of the creep and recovery functions from the Burgers model. Based on the result, the relationship between strain and stress under constant stress is given.
Kinematics of the Knee Joint in Deep Flexion: An X-Ray Study
Authors: Kelly Brian P. , Hefzy Mohamed Samir , Cooke Derek T. D. V. , Harrison Laurie A. 
Published: July 2023

Abstract
There are design limitations of about 140 degrees of knee flexion on existing knee prostheses (Scuderi, et al., 1989). This represents a functional deficit, especially in the Middle East and other populations that have social and cultural requirements for squatting and kneeling. In order to develop new artificial joints that will allow for a larger range of motion, more needs to be understood about how normal knees work. The data available in the literature that describe knee mechanics is limited in that information for flexion past 140° is not available (O’Connor and Zavatsky, 1990). The purpose of this study is to evaluate normal knees, past 140° of flexion, using radiographs.
A New Structural Model for Vertebral Trabecular Bone and Preliminary Applications to the Study of Osteoporosis
Authors: Overaker David W. , Cuitiño Alberto M. , Langrana Noshir A. , Zimmerman Mark C. 
Published: July 2023

Abstract
The symmetry of trabecular bone architecture depends on the loading environment. The vertebrae of the spine are loaded primarily in one direction (axial), so that the trabecular bone often develops into a symmetric arrangement of vertical columns with reinforcing horizontal struts[1, 2, 3]. A considerable amount of research has been done to quantify the effects of ageing and osteoporosis on the trabecular architecture[2, 4]. All have observed the same trend: trabecular thickness and density decrease with age. The horizontal trabecular thickness and density values decrease more rapidly than those of the vertical trabeculae. Also, vertical trabeculae are always thicker and more dense than horizontal trabeculae.
The Compressive Creep Behavior of the Porcine Intervertebral Disc Is Affected by Frozen Storage
Authors: Bass Elisa C. , Duncan Neil A. , Hariharan Jayaram S. , Lotz Jeffrey C. 
Published: July 2023

Abstract
The mechanical properties of the intact intervertebral disc may change if the specimen has been frozen prior to testing. Previous studies of various tissues and of the time-independent behavior of the intact disc have yielded conflicting results. The effect of frozen storage on the time-dependent behavior of the intact disc has not been investigated. We measured the displacement vs. time response of fresh and fresh-frozen intact IVDs subjected to repeated cycles of compressive creep and relaxation, and analyzed the results using a 3-parameter fluid transport model. Frozen storage dramatically affected the time-dependent behavior of the disc in compression, and permanent damage to the disc is indicated.
Non-Contact Evaluation of In-Situ Surface Strain Distribution of the Anterior Cruciate Ligament
Authors: Runco Thomas J. , Sakane Masataka , Woo Savio L.-Y. 
Published: July 2023

Abstract
Quantitative data on the strain and strain distribution in the anterior cruciate ligament (ACL) during knee motion can help to characterize the complex role of this ligament and lend insight into injury mechanisms of the ACL [2]. In-vitro studies have examined the elongations of different fiber bundles within the ligament [1, 4, 5, 7]. Using a Hall effect transducer attached to the anteromedial (AM) aspect of the ACL, in-vivo data on the strain behavior in the ACL during passive and active knee flexion as well as during various exercises have been obtained [3]. The objective of this study was to develop a non-contact approach to quantify the in-situ surface strains along the ACL. This approach was then used to test the hypothesis that the strain distribution along the ACL is uneven.
Transition to Turbulence in a Bifurcating Airway Model
Authors: Ueda Yoshiro , Okaniwa Takashi , Oka Kotaro , Tanishita Kazuo 
Published: July 2023

Abstract
Transition to turbulence in oscillatory How has been studied in a bifurcating airway model. Velocities were measured with a two-colour laser-doppler velocimeter. In the parent tube the large velocity gradient of “V” shaped velocity profile produces turbulence near the tube center in the expiratory phase of the flow cycle. On the other hand in the the inspiratory phase of the flow cycle, turbulence occurs in the tube center in the daughter tube.
Windkessel Modeling of Cardiac Afterload in the Stage 21 and 24 Chick Embryo
Authors: Kalegaonkar Shrikant , Kempski Mark H. 
Published: July 2023

Abstract
Cardiac function and vascular hemodynamics in the adult are primarily regulated through neural control mechanisms. However, functional hemodynamic control during primary cardiac development occurs prior to central nervous system development [Pappano 77]. Studies in our laboratory have shown that peak volumetric blood flow rate is amplitude modulated in the preinnervated embryo [Kempski 93]. This peak amplitude variability suggests an early mechanism for hemodynamic regulation which supplements beat-to-beat regulation via Frank-Starling mechanisms. We speculate that changes in vascular flow impedance may be the mechanism of hemodynamic regulation prior to the advent of neural control [Kempski 93]. We hypothesize that these changes can be modeled using three-element Windkessel analogs of cardiac afterload (Fig. 1).
Reduced-Order Modeling for Hyperthermia: An Extended Balanced-Realization-Based Approach
Authors: Mattingly M. , Bailey E. A. , Dutton A. W. , Roemer R. B. , Devasia S. 
Published: July 2023

Abstract
The problem: Hyperthermia when used as an adjuvant to normal radiation therapy significantly increases treatment response rates in cancerous tumors. The goal of a hyperthermia treatment is to elevate the tumor tissue temperature to therapeutic levels, while maintaining the surrounding normal tissue at safe temperature levels.
To achieve these treatment goals, researchers have investigated the use of model based controllers for hyperthermia. These model based controllers perform well; however, the complex and inhomogeneous nature of the tumor and surrounding tissue leads to large finite element, bio heat transfer models which make real time control computationally intractable. Hence, techniques are needed to reduce the model size, while retaining an acceptable degree of accuracy in the input-output map (the map from the applied power to the measured temperatures).
A General Mathematical Multibody Model for Diarthrodial Joints: Application and Validation Using the Patellofemoral Joint
Authors: Kwak S. D. , Ateshian G. A. , Blankevoort L. , Ahmad C. S. , Gardner T. R. , Grelsamer R. P. , Henry J. H. , Mow V. C. 
Published: July 2023

Abstract
An accurate mathematical model of a diarthrodial joint can be a powerful tool in investigating the mechanical behavior of a joint and the effects of pathologies and surgical procedures. Recognizing the potential of such a model, many investigators have previously developed mathematical models of a diarthrodial joint (e.g., Wismans et al., 1980; Blankevoort et al., 1991; Hirokawa, 1991; Hefzy and Yang, 1993; Heegaard et al., 1995). Most of these models, however, were limited to two body models specific to a particular joint; moreover, many of these models have not been thoroughly validated by comparing their results to experimental results obtained from the same individual specimen. Therefore, a more general mathematical 3-D multibody model capable of simulating different joints has been developed. It incorporates accurate joint geometry and wrapping of ligaments and tendons around bony or articular surfaces to predict the equilibrium pose, contact areas, contact forces, and ligament forces. Furthermore, to validate the model, the model has been applied to the patellofemoral joint, and its predictions were compared to actual experimental results.