bluuebunny/crossref_metadata_2025_split huggingface dataset:
Medial Placement of the Patellar Button Improves Contact Pressure Distribution Following Total Knee Arthroplasty
Authors: Petrella Anthony J. , Karmas Alexandros , Miller Mark C. , Berger Richard A. , Rubash Harry E. 
Published: December 2021

Abstract
Total knee arthroplasty is now a common and successful means of treating osteoarthritis and other degenerative conditions in the knee joint. Historically, mechanical failures (e.g. button loosening or separation from the metal backing) and chronic subluxation have been among the most common complications associated with the patello-femoral joint. Advances in fixation, implant design, and surgical technique have lead to a decrease in the incidence of mechanical failures, but restoration of stable function to the distal extensor mechanism remains challenging. The center of pressure (COP) on the patellar implant is an indication of the distribution of contact forces on the device and of the stability of patellar tracking. An eccentric COP suggests the possibility of subluxation, high contact stresses, and increased patellar wear. The main objective of this study was to determine the affect of medial-lateral patellar placement on the COP of the patellar implant. It was hypothesized that medial-lateral placement of the patella would have a significant effect on the COP.
A Triphasic Analysis of Indentation on Articular Cartilage
Authors: Sun D. N. , Guo X. E. , Lai W. M. , Mow V. C. 
Published: December 2021

Abstract
The indentation experiment is one of the most frequently used methods for studying biomechanical properties of articular cartilage. This experimental configuration is attractive because it does not require special specimen preparation [1,2]. Indentation can be performed on an articulating surface with the cartilage attached on the bone, a condition resembling closer to the physiologic and anatomic condition than compression of osteochondral plugs excised from the joint surface. It provides a non-destructive method to determine the variation of cartilage properties over the joint surface and has a potential for in vivo applications of determining mechanical and electrochemical properties of articular cartilage. Numerous theoretical and numerical analyses of indentation on articular cartilage have been performed and used to calculate the in situ mechanical material constants (Ha, k, v) of the tissue [e.g., 1–3].
A Large Strain Hyperelastic Constitutive Model for Intraluminal Thrombus From Abdominal Aortic Aneurysm
Authors: Wang David H. J. , Makaroun Michel S. , Webster Marshall W. , Vorp David A. 
Published: December 2021

Abstract
Rupture of abdominal aortic aneurysm (AAA) occurs when the wall stress acting on the dilated aortic wall exceeds the strength of the tissue. Therefore, accurate estimation of the wall stress distribution in AAA may be a clinically useful tool to predict their rupture. A majority of AAA contains a laminated, stationary, intraluminal thrombus (ILT) (Harter et al., 1982). Previous investigations have shown that ILT may significantly alter the wall stress acting on AAA (Inzoli et al., 1993; Mower et al., 1997; Stringfellow et al., 1987; Vorp et al., 1998; Di Martino et al., 1998). However, all of those studies used a simplified linear elastic model for ILT. This is inappropriate and can lead to inaccuracies since both AAA wall and contained ILT undergo large deformation during the cardiac cycle (Vorp et al., 1996). Therefore, to accomplish accurate stress analysis of AAA, appropriate constitutive models for both the wall and ILT are necessary. Our group has previously proposed a finite strain constitutive model for the AAA wall (Raghavan et al., in press). The purpose of this work was to derive a more suitable constitutive model and the associated mechanical properties for the ILT within AAA.
Equivalent Mixed “PHETS” and “MPHETS” Poroelasttc-Transport-Swelling Finite Element Models for Soft Biological Tissues
Authors: Simon B. R. , Williams S. K. , Liu J. , Nichol J. W. , Rigby P. H. , Kaufmann M. V. 
Published: December 2021

Abstract
A soft hydrated tissue structure can be viewed as a “PETS” (poroelastic-transport-swelling) model, i.e., as a continuum composed of an incompressible porous solid (fibrous matrix with fixed charge density, FCD) that is saturated by a mobile incompressible fluid (water) containing mobile positively (p) and negatively (m) charged species. Previously, we described two PETS models — a “semi-mixed” porohyperelastic PHETS model (Simon et al. 1998) and a “fully mixed” MPHETS model (Simon et al. 1999) using FEMs (finite element models) that included geometric and material nonlinearity and coupled electrical/chemical/mechanical transport of the fluid and charged species. Here, we demonstrate the equivalence of the PHETS and MPHETS formulations that are useful when the solid and fluid materials are incompressible and the electrical-chemical potential and mechanical-osmotic pressure fields are discontinuous at material interfaces.
A Novel Technique for Measuring Regional Deformation With High Spatial Resolution in the Beating Heart
Authors: Gaudette Glenn R. , Chiang Fu-Pen , Todaro Joseph , Krukenkamp Irvin B. 
Published: December 2021

Abstract
Many diseases result in a heterogeneous distribution of regional function. This results in the need for a technique that can accurately measure deformation with high spatial resolution. We have developed computer aided speckle interferometry (CASI) to accomplish this task. Instead of tracking individual particles, CASI tracks clusters of particles. In the isolated beating rabbit heart, CASI was used to determine the simultaneous displacement of 625 points located in a region approximately 5.5 × 5.5 mm. These displacements were plotted as a function of the left ventricular pressure to generate a regional work loop, which has conventionally been used to determine regional function in the myocardium. In summary, we have developed a technique to measure regional function with high spatial resolution and applied it to the beating heart.
Carpal Kinematics During Radial Ulnar Deviation
Authors: Patterson Rita M. , DaSilva Manuel F. , Viegas Steven F. , Goslings J. C. 
Published: December 2021

Abstract
This study investigates carpal kinematics during a wrist Radial/Ulnar deviation motion using high speed video data acquisition. A cadaver forearm was stabilized allowing unconstrained excursion of the wrist for passive range of motion.
Capitate/radius and 3rd metacarpal/radius angles were calculated to determine which measurement would be best for determining global wrist angle. The average difference in angle between the capitate and third metacarpal was 1.3 ± 1.3 degrees with a maximum difference of 5.0 degrees. Hence, the capitate-third metacarpal joint can be considered ridged.
The proximal wrist joint (R/L angle) contributed 15.1 degrees to global wrist radial ulnar deviation and the midcarpal joint (C/L angle) contributed 20.6 degrees to global wrist radial ulnar deviation (43.0% and 55.8%, respectively, of the 36.4° total wrist ROM). Radio-scaphoid angles averaged 16.8 degrees (46.5% of the 36.4° total wrist ROM). The radio-lunate joint and the capito-lunate joint contribute equally to global wrist radial ulnar deviation.
This new combination of motion analysis and 3D reconstructions of CT images affords a high speed, dynamic analysis of kinematics. It shows that normal carpal kinematics, during wrist radial/ulnar deviation, does not have an instantaneous screw axis (ISA) fixed in or limited to the capitate. In addition, the ISA data provides evidence that translational motion is a real and measurable component of normal carpal motion. This would change the understanding of carpal kinematics from previous studies, which suggested that the center of rotation was fixed in the capitate.
Finite Element Analysis of MOD Cavity Depth in a Restored Tooth
Authors: Lin Chun-Li , Chang Chih-Han , Wang Chau-Hsiang , Lee Huey-Er 
Published: December 2021

Abstract
Numerous studies have confirmed a correlation between the restored tooth fracture and the cavity design parameters. Improper geometric design of cavity could increase the unfavorable stresses of remaining tooth structure and cause fracture. However, the quantitative guideline for cavity preparation is unclear. This study developed an automatic mesh generation tool and employed finite element method to examine the stress distribution with different cavity depth designs in class II MOD restoration. The results indicated that for deeper cavity designs the unfavorable stress gradient was evident, therefore, the existence of a pulpal wall is essential.
Finite Element Analysis of Fiber Composite Dental Bridges: The Effect of Length / Depth Ratio and Load Application Method
Authors: Nowak Michael D. , Haser Kim , Goldberg A. Jon 
Published: December 2021

Abstract
Work is continuing in the evaluation of orthotropic fiber reinforce composites for use in the construction of dental bridges. Finite Element Analysis (FEA) models were constructed based upon mechanical testing of end clamped specimens center loaded with a metal indenter. Various length / depth specimens were evaluated in the elastic range, with a variety of load magnitudes.
Separate FEA models utilized single point loading, distributed loading, and the construction of a model indenter. Deflections at the loading point demonstrated that all models presented similar findings to those seen in mechanical testing. The similarity of results between the single loading point and the indenter FEA models suggest that either is reasonable for elastic range testing. The significantly shorter CPU run times for the single force models suggest that this may be the best means by which to model orthotropic fiber reinforced dental composites in the elastic range.
Undergraduate and Graduate Design Projects
Authors: Devey Gilbert B. 
Published: December 2021

Abstract
The National Science Foundation (MSF) was established in 1950 as an Independent Agency of the Federal Government with the broad mission to promote and advance scientific progress in the U.S. This is accomplished primarily by supporting research and education in all disciplines of the natural and social sciences, mathematics, and engineering. Support is provided principally in the form of grants awarded on a competitive basis under a rigorous peer review process; NSF does not conduct research itself. In 1992, NSF defined a project eligible for support as bioengineering research as one “...with diagnosis or treatment-related goals, that applies engineering principles to problems in biology and medicine while advancing engineering knowledge is eligible for support. Bioengineering research to aid persons with disabilities is also eligible”.1 Bioengineering at NSF has two defined programs: 1 - “Biochemical Engineering”, and 2 - a two-component activity “Biomedical Engineering” (BME) and “Research to Aid Persons with Disabilities” (RAPD). Undergraduate and Graduate Design Projects is part of the RAPD component of the program.
Injury Criteria of Child and Adult Dummies
Authors: Sances Anthony 
Published: December 2021

Abstract
Human injury tolerance is difficult because of physical differences between humans and animals, dummies and cadaver tissue. Human volunteer testing has been done but at sub injurious levels (Stapp, 1986 and Ewing, 1972). Considerable biomechanical engineering and tissue studies exist for the adult human cadaver however little is available for the pediatric population (Kumaresan, 1999). A number of dummies have recently been made available principally for airbag testing to bridge the gap between the 50 percentile hybrid III male dummy and the 95 percentile male dummy. (Kleinberger. 1998) The air bag dummies including the 12-month old CRABI dummy, 3-year old Hybrid III dummy, 6-year old Hybrid III dummy, the Hybrid III small female, Hybrid II mid-size male and 95 percentile large male are discussed.
Beyond Whiplash: Impact Evidence in Severe Spinal Injury
Authors: Syson Stephen R. 
Published: December 2021

Abstract
Whiplash injuries often occur without noticeable damage to the interior of a vehicle, and only minor damage to the vehicle exterior. Severe spinal trauma is, however, almost always associated with a forceful head or torso contact. This paper is intended to help the investigator of a collision find and document physical evidence of a contact, in the event such a witness mark exists. A brief outline of a suggested investigation methodology includes the types of marks to look for, and how to hypothesize where to look.
Trends in the Design and Manufacture of Footwear
Authors: Thompson David E. , Dobson Gregory T. , Shaffer Howard , Cox Jordan J. 
Published: December 2021

Abstract
There are many new challenges facing the footwear industry as they seek to gain a technological advantage to offset the lower cost of production from the Pacific Rim. In fact, the use of technology in footwear is a very recent trend. There are many different approaches to the use of technology in footwear, and this panel seeks to highlight some of the issues involved and to raise the level of discourse in this important field. In addition to the manufacturing challenges within the industry, there are other critical new questions that are being discussed.
Low Velocity and Compression-After-Impact Response of Pin-Reinforced Sandwich Composites
Authors: Vaidya Uday K. , Kamath Mohan V. , Hosur Mahesh V. , Haque Anwarul , Jeelani Shaik 
Published: December 2021

Abstract
In the current work, sandwich composite structures with innovative constructions referred to as Z-pins, or truss core pins are investigated, in conjunction with traditional honeycomb and foam core sandwich constructions, such that they exhibit enhanced transverse stiffness, high damage resistance and furthermore, damage tolerance to impact. While the investigations pertaining to low velocity impact have appeared recently in Vaidya et al. 1999, the current paper deals with compression-after-impact studies conducted to evaluate the residual properties of sandwich composites “with” and “without” reinforced foam cores.
The resulting sandwich composites have been investigated for their low velocity (&lt; 5 m/sec) impact loading response using instrumented impact testing at energy levels ranging from 5 J to 50 J impact energy. The transverse stiffness of the cores and their composites has also been evaluated through static compression studies. Compression-after-impact studies were then performed on the sandwich composites with traditional and pin-reinforcement cores. Supporting vibration studies have been conducted to assess the changes in stiffness of the samples as a result of the impact damage. The focus of this paper is on the compression-after-impact (CAI) response and vibration studies with accompanying discussion pertaining to the low velocity impact.
Evaluation of Heat Damage on B4C Particulate Reinforced Aluminum Alloy Matrix Composite Using Acoustic Emission Techniques
Authors: Shan D. , Nayeb-Hashemi H. 
Published: December 2021

Abstract
Aluminum alloys reinforced with B4C particle of average particle size of 10.5 μm and 20.9 μm were exposed to 535°C for various duration. The material degradation was evaluated by both mechanical and acoustic emission monitoring during tensile test. The micromechanisms of fracture changed from particle fracture and debonding, for as received specimens, to particle/matrix debonding after exposure to high temperature. The cumulative acoustic emission (AE) events during post heat exposure reduced with the increase of heal damage on the specimen. A Weibull probability distribution function that incorporates heat damage and relates to the cumulative events is developed. This model could be used to evaluate the extent of heat damage to a composite specimen.
Low Cycle Fatigue of Unidirectional Glass/Epoxy Composites
Authors: Harik V. M. , Klinger J. R. , Fink B. K. , Bogetti T. A. , Paesano A. , Gillespie J. W. 
Published: December 2021

Abstract
Low cycle fatigue (LCF) behavior of unidirectional polymer matrix composites (PMCs) reinforced with glass fibers is investigated. LCF conditions involve high loads reaching up to 90% of the material ultimate strength. LCF characterization of PMCs is carried out under tension-tension fatigue loading to identify the key physical phenomena occurring in PMCs under LCF conditions and to determine their unique characteristics. Analysis of experimental data indicates that finite strain rates, large strains and stress ratios may affect LCF behavior of PMC structures and the property degradation rates.
Mechanical Properties of Flat Braided Composites With a Circular Hole
Authors: Ohki Takeru , Ikegaki Shinya , Kurasiki Ken , Hamada Hiroyuki , Iwamoto Masaharu 
Published: December 2021

Abstract
In this study, fracture behavior and strength in the flat braided bar with a circular hole were investigated by static and fatigue test. Two type of specimens were prepared. They are a braided flat bar with an integrally-formed braided hole and a braided flat bar with a machined hole. Moreover, we also examined a specimen that had a metal pin inserted at the circular hole. This specimen was subjected to a static tensile test. The results of the tensile tests indicate that the strength of the flat bar with a braided hole was larger than that of the one with the machined hole. Furthermore, from the results of the fatigue tests, the flat bar with the braided hole showed higher fatigue property than that of the one with the machined hole.
Identification of In-Plane Elastic Constants of Composite Laminates Using Measured Strains
Authors: Kam T. Y. , Lin C. H. , Wang W. T. 
Published: December 2021

Abstract
A method for nondestructive evaluation of material constants of composite laminates is presented. An error function is established to measure the differences between the theoretically and experimentally predicted strains. The identification of the material constants is formulated as a constrained minimization problem in which the material constants are determined to make the error function a global minimum. A global minimization method together with a technique for normalizing the gradient of the objective function are used to solve the above minimization problem. The applications of the proposed method are demonstrated by means of several examples on the material constants identification of laminated composite cylindrical pressure vessels.
Modeling the Debonding Behavior of Step-Tapered Patches: Analytical Solutions and Numerical Analysis of Selected Structures
Authors: Karlsson A. M. 
Published: December 2021

Abstract
A common method to strengthening or stiffening a weak part of an airplane structure is to adhere a patch over the inferior surface. Typically, this is done in order to prevent a crack from initiating, or to prevent an already existing crack from growing. Evaluation of the efficiency of the patch has traditionally been done with respect to the extent of crack growth, (e.g. Park et al. 1992, and Paul and Jones, 1992), which of course is of crucial interest. However, the integrity of the patched system needs to be considered as well, since the failure of the composite system (formed by the patch and the base structure) may lead to a rapid growth of the preexisting crack in the base structure and may have overall catastrophic consequences. In this study we are therefore interested in investigating the initiation of debonding between the patch and the base structure, as well as the extent and stability of the debonding.
Early studies we conducted with respect to debonding suggested that relative long and relative compliant patches were preferred. Furthermore, an investigation regarding the effects of edge tapering on the debonding behavior showed that there are situations where a beveled edge may increase the propensity for debonding, requiring careful selection to achieve a suitable taper angle. In the present study, we investigate the integrity of the composite system for a base structure made from aluminum, and the patch made from aluminum or fiber reinforced epoxy, where both carbon and glass fiber are studied. In particular, we compare the materials selection in the patch, and for the case of a fiber-reinforced epoxy we also discuss the lay-up sequence.
To model the debonding behavior, an analytical model developed previous is extended to allow for the current materials properties. This model is fully self consistent and includes a Griffith type fracture criteria which yields the condition for the propagating bond zone boundary. The model also considers the unbonded part of the patch, which has earlier been shown to be in either of three configurations: (i) full sliding contact between the unbonded part of the patch and the base structure, (ii) only the edge of the patch remains in sliding contact with the base structure, or (iii) the patch has totally lifted of the base structure.
Results for both flat and curved structures are presented, as well as for a range of loading and boundary conditions. Among other results, it is seen that the degree of tapering is a more important parameter than the stacking sequence is with respect to the initiation and extent of debonding. Furthermore, a simplified testing method is discussed. In this method, the critical load for a case of simple boundary and loading conditions for a particular material system can be directly translated to the critical load for a more complicated structure.
A Hystersis Model for Piezoceramic Materials
Authors: Smith Ralph C. , Ounaies Zoubeida 
Published: December 2021

Abstract
This paper addresses the modeling of nonlinear constitutive relations and hysteresis inherent to piezoceramic materials at moderate to high drive levels. Such models are necessary to realize the full potential of the materials in high performance control applications, and a necessary prerequisite is the development of techniques which permit control implementation. The approach employed here is based on the quantification of reversible and irreversible domain wall motion in response to applied electric fields. A comparison with experimental data illustrates that because the resulting ODE model is physic-based, it can be employed for both characterization and prediction of polarization levels throughout the range of actuator operation. Finally, the ODE formulation is amenable to inversion with facilitates the development of an inverse compensator for linear control design.
Lagrangian and Lagrange Equation of Motion for Fractionally Damped Systems
Authors: Agrawal Om Prakash 
Published: December 2021

Abstract
Damping properties of various materials have recently been used as active and passive control parameters in smart structures. In these applications, the damping force is considered as proportional to velocity. In recent years, many investigators have demonstrated that the damping characteristics of a material can be modeled more accurately using a fractional derivative. Traditionally, Newton’s law is used to model such nonconservative systems, and when a Lagrangian, Hamiltonian, variational or other energy based approach is used, it is modified so that the resulting equations match with those obtained using Newtonian’s approach. In this paper we present a new Lagrangian containing derivatives of fractional orders, and a new Lagrange equation of motion for systems whose damping characteristics are described by a fractional derivative model. The method results in a state space type representation of the system. The method is applied to find the equations of motion of m/n order fractionally damped systems. Several examples are considered to show that the present scheme leads to a correct set of equations. It is hoped that this approach will help one to develop Hamiltonians, Jacobi theory, and other approaches in mechanics for systems containing fractional derivatives.