bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hemodynamic Simulations of Flow in Normal and Stenotic Carotid Arteries
Authors: Berger Stanley A. , Stroud Jennifer S. , Rayz Vitaliy 
Published: November 2021

Abstract
Much of the recent work attempting to simulate arterial flows has been motivated by attempts to elucidate the relationship between flow in the arteries and atherogenesis, and the focalization of plaque development. The aspect of the flow of most interest in this context was wall shear stresses, there being substantial evidence that the most susceptible sites are where shear stresses are low, or change rapidly in time or space [1]. These conditions are most likely to occur where there are sudden changes in flow geometry, and/or when the flow is unsteady. (For a recent review see [2].) We have studied flow in the carotid arterial bifurcation. Carrying out extensive simulations of the fully three-dimensional unsteady flow in realistic normal carotid bifurcation geometries allows us to identify the more dangerous sites for plaque development according to the above criteria. In the later stages of progression of atherosclerotic disease the relevant issues become vessel occlusion, embolic events, or plaque rupture, especially since recent clinical investigations have suggested that the danger posed by a particular plaque depends not only on the degree of occlusion but also on the so-called “vulnerability” of the plaque, the tendency of the plaque, depending on its composition, to fracture and rupture. To address these issues we have simulated flow in realistic severely stenotic carotid bifurcations toward the end of identifying critical features of plaque geometry and “risk factors” for plaque fracture and rupture.
Micromechanics of Fibroblast Contraction of a Collagen-Gag Matrix
Authors: Freyman Toby M. , Yannas Ioannis V. , Pek Yuri-Shona , Yokoo Rayka , Gibson Lorna J. 
Published: November 2021

Abstract
Contractile fibroblasts play a major role in the synthesis and remodeling of scar tissue following dermal injury. Inhibition of dermal wound contraction by contractile fibroblasts, using a collagen-GAG matrix, has been linked to the blocking of scar formation[1]. Scar tissue is mechanically and functionally inferior to the dermal tissue which it replaces. Specifically, scar tissue is weaker, physically disfiguring, and can lead to restricted joint mobility.
Injection Molding of Tissue Engineered Tympanic Membrane Patches Utilizing Computer-Aided Design
Authors: Hott Morgan E. , Beane Richard M. , Megerian Cliff , Bonassar Lawrence J. 
Published: November 2021

Abstract
Over two million tympanostomy tubes are inserted annually in the United States, making this the most commonly performed of all surgical procedures (Isaacson 1996). In approximately 10% of cases the patient treated with tympanostomy tubes is left with a permanent perforation of the tympanic membrane that requires surgical repair. Current surgical technique involves grafting of an autologous tissue such as temporalis fascia or tragal cartilage to the perforated membrane (Paterson 1999). This is an involved surgical procedure requiring general anesthesia. We propose tissue engineering an autologous cartilage tympanic membrane patch. If successful this approach has the potential to transform an operating room procedure to an office procedure. This would provide tremendous healthcare savings, and potentially obviate the need for tens of thousands of children to undergo general anesthesia.
Effect of Cryoprocessing on Umbilical Cord Blood for Hematological Disorders
Authors: Pal Subrata , David R. Sheba N. 
Published: November 2021

Abstract
Cellular therapies promise to become major therapeutic modalities of this new century. The hematopoietic restoration with umbilical cord blood transplant can be a useful source of hematopoietic stem cells for routine bone marrow reconstitution. Thus it can be used as an effective source of stem cells for the treatment of various hematological disorders like leukemia, thalessaemia, aplastic anemia and it also can be used to replace the damaged tissue in various pathological conditions like Parkinson’s disease, Alzheimer’s, osteoarthritis etc. The advantage of the umbilical cord blood transplant being, use of unrelated umbilical cord blood transplantation with upto 2 to 3 HLA mismatch (Wagner et al, 1996).
An Axisymmetric Elastic Layered Half-Space Model for Micropipette Aspiration of the Chondrocyte Pericellular Matrix
Authors: Alexopoulos Leonidas G. , Haider Mansoor A. , Guilak Farshid 
Published: November 2021

Abstract
Articular cartilage is an aneural, avascular connective tissue that serves as the resilient load-bearing surface at the articulating ends of diarthrodial joints. A sparse single population of cells known as chondrocytes maintains the extracellular matrix (ECM) of this tissue through a balance of anabolic and catabolic activities. The mechanical environment of chondrocytes, in conjunction with other genetic and environmental factors (e.g., growth factors, cytokines), plays an important role in regulating cartilage homeostasis and, as a consequence, the health of the joint.
An Exploration of Cell Stress and Deformation Under Shear Flow
Authors: Guo X. Edward , Takai Erica , Liu Kai , Wang Xiaodong 
Published: November 2021

Abstract
The biological response of bone cells (osteoblasts and/or osteocytes) to mechanical loading is an important basic science topic in the mechanism of mechano-signal transduction in bone adaptation to mechanical loading. The characterization of this mechanism of signal transduction is crucial in the understanding of the etiology of age-related bone loss, bone loss during space flight and the optimal design of implants for total joint replacements. It has been hypothesized that deformation-generated fluid shear stress is one of the major mechanical stimuli that bone cells respond to. Many in vitro experiments utilize a parallel-plate flow chamber by imposing fluid shear stress on cultured osteoblasts. For example, changes in intracellular Ca++ levels and mitogen-activated protein kinase (MAPK) phosphorylation has been quantified in response to applied shear flow [1,2]. In these studies, the flow shear stress at the wall of the flow chamber τ wall = 6 μ Q w h 2 , where Q is the volumetric flow rate, w and h are the width and height of the flow chamber, respectively, and μ is the media viscosity. However, this wall shear stress may not indicate the actual stress state which bone cells experience, which depends on the details of the flow-cell interaction, including the mechanical properties of the cell, the attachment condition of the cell to the wall as well as the cell density. In order to obtain a quantitative relationship between the biological response of bone cells to applied shear flow, it is necessary to quantify in detail the flow-cell interaction in a typical shear flow experiment. The objective of this study was to quantify the shear stress within the cell under applied shear flow, incorporating fully coupled flow and solid deformation analyses using the finite element technique. Specifically, we examined the influence of the elastic modulus of the cell and the spacing distance between cells on the shear stress within the cell.
Hybridization Dynamics and Kinetics of Fret-Enhanced Molecular Beacons
Authors: Tsourkas Andrew , Xu Jason , Bao Gang 
Published: November 2021

Abstract
Many human diseases start with a defect in the genome. Cancer, for example, is a genetic disease that arises from a single cell that behaves abnormally, dividing uncontrollably and leading, eventually, to the development of a tumor. A critical step in diagnosing and treating cancer is to detect cancer cells that result from the mutated genes. In spite of the extensive biomedical research efforts during the last few decades, it is still difficult to detect cancer at its early stages — when a cancer is diagnosed it is often too late to cure. A novel way of achieving early detection of cancer is to detect mRNA transcripts that arise from mutated genes in living cells [1]. We have developed a FRET-enhanced molecular beacons methodology which, combined with the state-of-the-art fluorescence imaging techniques, has the potential to detect cancer cells. FRET (Fluorescence resonance energy transfer) refers to the non-radiative transfer of energy from a donor molecule to an acceptor molecule through dipole-dipole coupling. As shown schematically in Figure 1, molecular beacons are dual labeled antisense oligonucleotides (ODNs) with a fluorophore (A or D) at one end and a quencher (Q) at the other; they are designed to form a hairpin structure in the absence of a complimentary target such that fluorescence of the fluorophore is quenched. Upon hybridization with the target mRNA, the molecular beacon opens up, leading to fluorescence [2,3].
The Modeling of Mechatronic Servo Systems and Vibration Control
Authors: Zou Junzhong , Jing Zhongliang , Nakamura Masatoshi , Luo Albert C. J. 
Published: November 2021

Abstract
A mathematical model of industrial mechatronic servo systems is developed and a method for determining the servo parameters without vibration in the servo controller is proposed. The effectiveness of the method is verified through the experimental results.
Multi-Body Contact Dynamics Modeling of Roll Mechanisms in Paper Manufacturing Systems
Authors: Keskinen Erno , Launis Sirpa , Kivinen Juha-Matti 
Published: November 2021

Abstract
A multi-body contact dynamics formulation is introduced to model the dynamic motion of roll mechanisms typical for paper manufacturing systems. Physical contact forces acting on the bodies in the joints are connecting the links of roll mechanisms together instead of purely kinematic constraints used in existing classical algorithms. In a similar way, external contacts between rolls manipulating the paper web are modeled as contact line loads in normal pressing and tangential traction directions. In the case study the loading dynamics of a paper finishing unit used in paper industry has been simulated in order to find out dynamically stable dimensioning for the critical parts in a new four-bar-linkage roll loading mechanism.
Induced Vibration of Suspension Bridges Traversed by Moving Vehicles
Authors: Esmailzadeh Ebrahim , Jalili Nader 
Published: November 2021

Abstract
An investigation into the dynamics of vehicle-structure interaction of a suspension bridge traversed by a moving vehicle is presented. The vehicle including the occupants is modeled as a half-car model with six degrees-of-freedom, and the bridge is assumed to obey the Euler-Bernoulli beam theory. Due to the continuously moving location of the loads on the bridge, the governing differential equations will have time-varying coefficients and hence, become rather complicated. The relationship between the bridge vibration characteristics and the vehicle speed is rendered, which yields into a search for a particular speed that determines the maximum values of dynamic deflection and the bending moment of the bridge. Results at different vehicle speeds demonstrate that the maximum dynamic deflection occurs at the vicinity of the bridge mid-span (±3%), while the maximum bending moment is found at ±20% of the mid-span. It is shown that one can find a critical speed at which the maximum values of bridge dynamic deflection and bending moment attain their global maxima.
Dynamic Interaction of a Moving Oscillator With an Elastically Supported Continuum
Authors: Chen Yonghong , Tan Chin An , Bergman Lawrence A. 
Published: November 2021

Abstract
In this paper, the problem of a simple oscillator traversing an elastically supported continuum is investigated. Numerical results for the shear force distribution of the continuum are obtained. To circumvent convergence difficulties associated with the evaluation of the shear force, an improved series expansion is derived. Effects of boundary flexibility on the shear force spatial and temporal distributions, as well as the series convergence properties, are examined. Results reveal the presence of a high amplitude, high frequency component in the shear force due to significant contributions of the higher order modal terms in the series expansion. This is important from the viewpoint of understanding the cumulative fatigue failure of the continuum. A useful and compact formula estimating the value of the support stiffness above which the boundary can be idealized as simply supported is also derived.
In-Plane Free Vibrations of the Double-Segment Compound Rotating Disks
Authors: Hamidzadeh Hamid R. , Karim Reza U. 
Published: November 2021

Abstract
An analytical method is presented for determination of vibration characteristics of high speed Double-Segment Compound Rotating disks. More specifically, a systematic approach based on established solution for linear in-plane vibration of each segment satisfying the displacement and stresses compatibility is developed. Fixed and free boundary conditions for the compound spinning annular disks are considered and natural frequencies and mode shapes of rotating disks are computed. The medium for each segment is considered to be a homogenous, isotropic, and elastic. The developed analytical solution was achieved by implementing two-dimensional plane stress theory. The modal displacements and stresses at both inner and outer boundaries are determined. The dimensionless natural frequencies for different modes, rotating speeds, and thickness ratios are computed. The effect of stiffness changes for each segment on the natural frequencies are also studied.
Crack Influences on the Vibration, Buckling and Parametric Instability of Plates
Authors: Vafai Abolhassan , Javidruzi Mahyar , Estekanchi Homayoon E. 
Published: November 2021

Abstract
The vibration, buckling and parametric instability behavior of a simply supported rectangular plate with a crack emanating from one edge, subjected to in-plane compressive periodic edge loading is studied in this paper. Several plates, each with a different dimension and crack length size are analyzed using an analytical approach. The results of this study show that the vibration, buckling and parametric instability behavior of plates with length to width ratio greater than unity are considerably affected by the crack length size.
Nonlinear Supersonic Flutter of Imperfect Circular Cylindrical Shells
Authors: Amabili M. , Pellicano F. 
Published: November 2021

Abstract
The aeroelastic stability of simply supported, circular cylindrical shells in supersonic flow is investigated by using both linear aerodynamics (first-order piston theory) and nonlinear aerodynamics (third-order piston theory). Geometric nonlinearities, due to finite amplitude shell deformations, are considered by using the Donnell’s nonlinear shallow-shell theory, and the effect of viscous structural damping is taken into account. The system is discretized by Galerkin method and is investigated by using a model involving up to 22 degrees of freedom, allowing for travelling-wave flutter around the shell and axisymmetric contraction of the shell. Asymmetric and axisymmetric geometric imperfections of circular cylindrical shells are taken into account. Results show that the system loses stability by travelling-wave flutter around the shell through supercritical bifurcation. Non-simple harmonic motion is observed for sufficiently high post-critical dynamic pressure. A good agreement between theoretical and existing experimental data has been found for the onset of flutter, flutter amplitude and frequency. Results show that onset of flutter is very sensible to small initial imperfections of the shells. The influence of pressure differential across the shell skin has also been deeply investigated. The present study gives, for the first time, results in good agreement with experimental data obtained at the NASA Ames Research Center more than three decades ago.
Elasto-Multi-Body Dynamics of Multi-Cylinder Internal Combustion Engine
Authors: Gupta S. , Kelly P. , Rahnejat H. 
Published: November 2021

Abstract
The paper presents a multi-body model of a 4-cylinder, 4-stroke diesel engine, incorporating component flexibility. The model also comprises engine firing order and experimentally measured combustion time history. The paper presents numerical predictions for conical motion of the flywheel due to combined torsion-deflection modes of the flexible crankshaft system. The half-engine order responses induce the complex 3-dimensional whirling motion of the flywheel, which is responsible for repetitive shock loading of the drivetrain system through impact with the clutch system. This leads to an assortment of noise and vibration concerns, one of which is the in-cycle vibration of the clutch system. Numerical prediction of this vibration response conforms well with the experimental findings, both of which are reported in this paper.
Development of an Innovative Space Boom
Authors: Lou Michael C. , Fang Houfei , Yang Ben , Palmer Nathaniel Lee 
Published: November 2021

Abstract
This paper presents the development of a new type of ultra-lightweight space boom, called the Self-deployable Spring Strip Boom or simply the S3 Boom. It describes the fundamental design concept and several variations of design configurations. Test results of proof-of-concept models are discussed and compared with results obtained by analytical simulations.
A Study on the Effect of Preview Uncertainties in Preview Control of Vehicle Suspensions
Authors: Vahidi Ardalan , Eskandarian Azim 
Published: November 2021

Abstract
The benefit of previewing the “future” road inputs in improving the performance of active suspensions of a vehicle has been demonstrated in many publications. It is shown that smoother and more effective control is possible when the preview length is increased up to a certain limit. Most of these studies assume perfect preview measurements in their numerical simulations. In a real scenario however, the presence of uncertainties can not be neglected. The uncertainties can be due to sensor measurement noise or false objects on the surface of the road. In order to gain an insight to the problem this paper addresses the influence of preview uncertainty on the performance of a preview controller. The stochastic optimal control scheme for preview control of a quarter-car suspension model is briefly presented. Then results of numerical simulations, which are carried out for various levels of uncertainty in the preview and for different preview lengths, are compared. These comparisons show that noise/uncertainty can be an issue with an adverse effect that sometimes increases with preview length. In other words, it is shown that controllers with longer preview can be more susceptible to noise. However the limits of tolerable noise are not very restrictive and the well-known benefits of preview can still be achieved if the measurement errors are maintained below a limited level.
Simplified FEM Model of Paper Machine Roll for Multibody Rolling Contact Analyses
Authors: Järvenpää Veli-Matti , Keskinen Erno K. 
Published: November 2021

Abstract
In this paper a finite element model of a rotating paper machine roll for nip unit rolling contact analyses is discussed. This work presented here is based on the earlier work of the authors presented in [1] and [2]. The major motivations for developing a tailored FE-model including the large spin rotation are firstly to include the complex vibration phenomena as the shell vibrations of the roll structure in the analyses and secondly to reduce the computational costs of the numerical simulations due to the large number of degrees of freedom. The approach used is the use of the modal analysis i.e. to express the dynamics of the roll in terms of the lowest eigenmodes. The equations of motion are at first written in the rotating coordinates and then in addition to this the equations are expressed by using the modal coordinates. Numerical tests executed show that this modeling technique reduces computational costs significantly. Furthermore, use of the (semidefinite) eigenmode basis maintains the vibration characteristics of the roll structure. For verification purposes a test model was constructed and these simulation results were compared to the standard geometrically non-linear finite element analysis.
Genetic Algorithm-Based Maximum Likelihood Parameter Estimation for Transit Buses
Authors: Xiao Jie , Kulakowski Bohdan T. 
Published: November 2021

Abstract
Vehicle dynamic models include parameters that qualify the dependence of input forces and moments on state and control variables. The accuracy of the model parameter estimates is important for modeling, simulation, and control. In general, the most accurate method for determining values of model parameters is by direct measurement. However, some parameters of vehicle dynamics, such as suspension damping or moments of inertia, are difficult to measure accurately. This study aims at establishing an efficient and accurate parameter estimation method for developing dynamic models for transit buses, such that this method can be easily implemented for simulation and control design purposes. Based on the analysis of robustness, as well as accuracy and efficiency of optimization techniques, a parameter estimation method that integrates Genetic Algorithms and the Maximum Likelihood Estimation is proposed. Choices of output signals and estimation criterion are discussed involving an extensive sensitivity analysis of the predicted output with respect to model parameters. Other experiment-related aspects, such as imperfection of data acquisition, are also considered. Finally, asymptotic Cramer-Rao lower bounds for the covariance of estimated parameters are obtained. Computer simulation results show that the proposed method is superior to gradient-based methods in accuracy, as well as robustness to the initial guesses and measurement uncertainty.
Performance of Developed Driving Simulator With Full Vehicle Model of Multibody Dynamics
Authors: Shiiba Taichi , Suda Yoshihiro 
Published: November 2021

Abstract
In this paper, the authors propose to apply the full vehicle model of multibody dynamics to driving simulator with 6 degrees of freedom motion system. By this proposal, the characteristics of driving simulator become very similar to the actual automobiles. It becomes possible to predict the performance of vehicle dynamics and the riding comfort by feeling test without prototyping automobile. To realize real-time calculation that is necessary for driving simulator, the authors proposed approximated real-time analysis method. By this method, real-time vehicle analysis of 2 ms step time of numerical integration is achieved with 91 degrees of freedom vehicle model.
Computer Simulation of the Dynamic Properties of a Complex Man-Railway Vehicle-Environment System
Authors: Grabarek Iwona , Choromański Włodzimierz 
Published: November 2021

Abstract
This paper presents a model of the driver-locomotive-environment system achieved through the integration of separate models simulating the locomotive’s mechanical properties and the driver’s behaviour. The paper is focused on the modelling and simulation of the “driver” subsystem — for this purpose, the theory of fuzzy sets is used to present the simulation results of the system’s behaviour during a specific manoeuvre.