bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Novel Trigger Mechanism for a Dual-Filter to Improve the State-of-Charge Estimation of Lithium-Ion Batteries
Authors: Yu Chuanxiang , Huang Rui , Sang Zhaoyu , Yang Shiya 
Published: November 2021

Abstract
State-of-charge (SOC) estimation is essential in the energy management of electric vehicles. In the context of SOC estimation, a dual filter based on the equivalent circuit model represents an important research direction. The trigger for parameter filter in a dual filter has a significant influence on the algorithm, despite which it has been studied scarcely. The present paper, therefore, discusses the types and characteristics of triggers reported in the literature and proposes a novel trigger mechanism for improving the accuracy and robustness of SOC estimation. The proposed mechanism is based on an open-loop model, which determines whether to trigger the parameter filter based on the model voltage error. In the present work, particle filter (PF) is used as the state filter and Kalman filter (KF) as the parameter filter. This dual filter is used as a carrier to compare the proposed trigger with three other triggers and single filter algorithms, including PF and unscented Kalman filter (UKF). According to the results, under different dynamic cycles, initial SOC values, and temperatures, the root-mean-square error of the SOC estimated using the proposed algorithm is at least 34.07% lower than the value estimated using other approaches. In terms of computation time, the value is 4.67%. Therefore, the superiority of the proposed mechanism is demonstrated.
Nonlinear Mechanics and Buckling Analysis of Composite Shells With Embedded Piezoelectric Actuators and Sensors
Authors: Varelis Dimitris , Saravanos Dimitris A. 
Published: November 2021

Abstract
Nonlinear mechanics for piezoelectric composite laminates and shells are presented which include nonlinear effects due to large displacements and rotations. The mechanics are incorporated into the mixed piezoelectric laminate theory. Using the mechanics, a nonlinear finite element method and an incremental solution are formulated for the nonlinear analysis of adaptive shell structures. An eight-node shell finite element is developed. The mechanics are applied to predict the buckling of laminated piezoelectric shells induced by combined electromechanical loading. Application cases quantify the mechanical buckling of composite circular beams and cylindrical panels with piezoelectric sensors, the piezoelectric buckling of active circular beams and shells, and the feasibility of active buckling compensation.
Buckling of Shear-Deformable Multi-Layered Rings due to Fluid-Pressure Loading
Authors: McNamara Jack , Liu Li , Waas Anthony M. 
Published: November 2021

Abstract
This paper is concerned with the analysis of composite rings subjected to external fluid pressure loading. Nonlinear equilibrium equations, linear stability equations, and critical fluid-pressure loads are found for thin multi-layered shear deformable rings. The extensions presented here can be shown to be generalizations of the theory given in [1]. The theory shows that introduction of multiple layers of material introduces coupling between bending and extension. The results are used to show that shear deformation is important when R h &lt; 10 , as well as when the ratio of through thickness shear modulus to Young’s modulus becomes small. The latter has consequences when composite materials are used for the ring layers. The results are also used to show that for coupling between bending and extension the critical fluid-pressure will increase or decrease depending on the stacking sequence. For the example presented in this paper, the predicted critical fluid-pressure loading was higher for the stiffer material located on the inside of a two-layer ring. In all cases, the theoretical results are compared to a finite element method analysis.
Thermo-Mechanical Instabilities in Bilaminate Shell Structures
Authors: Bottega W. J. , Rutgerson S. E. 
Published: November 2021

Abstract
The problem of an elastic bilaminate shell subjected to transverse pressure and a uniform temperature field is considered for plane strain/plane stress configurations. Closed form analytical solutions are obtained for the nonlinear problem, and a stability criterion is derived for situations where multiple equilibrium configurations of the structure are possible for a given value of the loading parameter (a combination of the normalized pressure and thermal moment). Critical behavior is seen to be dependent on two critical parameters, a critical value of the loading parameter and a critical value of the membrane force. Extensive numerical simulations based on these solutions reveal characteristic behavior of the system. This behavior includes, bifurcation buckling, asymptotic buckling, sling-shot buckling and pre-limit point snap-through buckling. It is seen that pre-limit point snap-through is pervasive and perhaps the norm, even for certain classic problems, and its degree is a function of the material properties of the structure.
Nonlinear Through-Thickness Behavior of a Toroidal Shell Using 2-D Finite Elements
Authors: Greer James M. , Palazotto Anthony N. 
Published: November 2021

Abstract
The use of two-dimensional shell finite elements is explored for finding the three-dimensional state of stress in a toroidal shell. The torus under study represents a 90-degree pipe elbow with a pressure load on a portion of its surface. Layer-wise polynomials are used to represent the transverse shear and normal stretch deformations in the shell. These functions are chosen such that displacements and stresses (but not strains) are continuous at the ply interfaces. Both isotropic and composite (cross-ply) versions of the shell are investigated, and the thicknesses of each are varied to see the effect on through-thickness behavior. Significant qualitative and quantitative differences in these behaviors are observed, particularly in the important direct through-thickness (peeling) stress. The contribution of the transverse deformations to strain energy is investigated and, in most of the shells studied, the thickness stretch component is found to be a greater contributor to strain energy than the transverse shear, though the transverse shear contribution is seen to vary more dramatically with changes in shell thickness.
A Multi-Factor Interaction Model (MFIM) for Damage Initiation and Progression
Authors: Chamis Christos C. , Minnetyan Levon 
Published: November 2021

Abstract
A Multi-Factor-Interaction-Model (MFIM) is briefly described to represent complex point material behavior in a single equation. The model is of product form in order to represent coupled interactions and to be computationally effective. The model describes a continuum or surface in space that represents the complex material behavior in terms of the various factors that affect a specified material behavior. The material specified behavior is inclusive of all material properties, mechanical, thermal, physical and effects thereon, such as temperature, time, cyclic loadings, etc. Sample cases results simulated by using MFIM are compared with test data to illustrate its versatility and its relevance to reality. These results show the MFIM can accurately predict metal matrix composite fatigue data and mechanical properties of a steel alloy. MFIM predicted results for the damage tolerance of a large shell made from structural steel subjected to internal pressure. Helpful guidelines for its effective use are also included.
Dynamic Mode I Fracture Toughness Test of Composites Using a Kolsky Bar
Authors: Sun C. T. , Han C. 
Published: November 2021

Abstract
Mode I dynamic delamination fracture was studied with two polymeric fiber reinforced composites. Wedge insertion fracture test on a Kolsky bar (or split Hopkinson pressure bar) apparatus was conducted. A speed about 1,000 m/s of Mode I delamination crack propagation was achieved using high rates of loading. Dynamic fracture and crack propagation were modeled by the finite element method. Dynamic initiation fracture toughnesses of both composites S2/8552 and IM7/977-3 were obtained. For IM7/977-3, dynamic fracture toughness of IM7/977-3 associated with the high speed of propagating crack was examined. It is found that the dynamic fracture toughness of the delamination crack propagating at speed up to 1,000 m/s approximately equals to the dynamic initiation fracture toughness, which is again approximately equal to the static fracture toughness.
Dynamic Fracture Behavior of Syntactic Epoxy Foams: Optical Measurements and Analysis
Authors: El-Hadek Medhat A. , Tippur Hareesh V. 
Published: November 2021

Abstract
Dynamic fracture behavior of syntactic foams made of thin walled microballoons dispersed in epoxy matrix is studied. Monotonic reduction in dynamic Young’s modulus with increasing volume fraction of microballoons is observed using ultrasonic pulse-echo and density measurements. The measurements are also in good agreement with the Hashin-Shtrikman lower-bound predictions for elastic porous solids. Dynamic crack initiation toughness and crack growth behaviors are examined using instrumented drop-tower tests and optical measurements. Crack initiation toughness measurements show a linear relationship with Young’s modulus over the entire range of volume fraction of microballoons studied. A proposed model based on a simple extension of micro-mechanics prediction agrees well with the measurements. The optical method of Coherent Gradient Sensing (CGS) has been used along with high-speed photography to record crack tip deformation histories in syntactic foam samples subjected to impact loading. Pre- and post-crack initiation events have been successfully captured and apparent dynamic stress intensity factor histories are extracted from the interferograms. Optically measured stress intensity factors at crack initiation and during crack growth also decrease with increasing volume fraction of microballoons. Increasing crack speeds with volume fraction of microballoons has become evident. No significant dependence of dynamic fracture toughness on crack speed is seen in any of the volume fractions studied.
Flexural Fatigue of PVC Foams
Authors: Kanny Krishnan , Mahfuz Hassan , Carlsson Leif A. , Thomas Tonnia , Jeelani Shaik 
Published: November 2021

Abstract
Flexural fatigue tests were performed on cross-linked PVC foams of densities in the range from 75 to 300 kg/m3 at a frequency of 3Hz and at a stress ratio, R = 0.1. S-N diagrams were generated, and the failure mechanisms were examined. The fatigue behavior was found to be similar to structural materials with a fatigue strength that decreased with increased stress and increased with increased foam density. The final failure event was catastrophic due to crack propagation initiating at the tension side of the beam. SEM analyses of unfailed and failed 300kg/m3 density foam specimens revealed cell wall cracking and densification of the foam. The densification contributed to stiffening of foam specimens. Viscoelastic parameters of the foams were determined at room temperature using a Dynamic Mechanical Analyzer (DMA) over a frequency range of 1–10Hz. For the virgin specimens it was found that the viscoelastic moduli and damping ratio were quite independent of frequency over this range of frequencies. Except for the lowest density foam (75kg/m3), the damping ratio was quite independent of foam density.
The Effect of Stitching on Compression Behavior of Stiffened Composite Panels
Authors: Suh Sung S. , Hahn H. Thomas , Han Nanlin , Yang Jenn-Ming 
Published: November 2021

Abstract
Failure of stiffened panels under compression is preceded by buckling of their skin and hence is affected by the presence of out-of-plane stresses. One of the promising methods of preventing premature delamination is stitching. The present paper discusses the effect of such stitching on compression behavior of blade-stiffened panels that were fabricated from plain weave AS4/3501-6 through resin film infusion process. Kevlar 29 yarn was used at a stitch density of 9.92 stitches per cm2. Some of the panels were damaged by drop-weight impact before compression testing. For comparison purposes unstitched panels with the same materials and dimensions were also tested under the same loading conditions. Stitching resulted in a 10% improvement in strength in the absence of any intentional damage. The beneficial effect of stitching was most obvious when the panels were impacted on a flange: a 50% improvement was observed in post-impact strength. However, stitching could not prevent stiffener from failure when impacted directly. Thus stitching had no beneficial effect when impact occurred on a stiffener. A buckling and post-buckling analysis was carried out using 3-D shell elements on the Abaqus. Predictions were in fairly good agreement with the experimental data.
Damage Control in Composite Laminates
Authors: Suvorov Alexander P. , Dvorak George J. 
Published: November 2021

Abstract
Several effects that fiber prestress may have on stress redistribution in the plies of composite laminates and in the phases of individual plies are illustrated. These include improvement of composite damage resistance under tensile mechanical loads, reduction/cancelation of interlaminar stresses at free edges of composite laminate subjected to thermomechanical loading, and stress relaxation in the matrix phase of viscoelastic composite laminates. Specific results are found for quasi-isotropic and cross-ply symmetric S-glass/epoxy and carbon/epoxy AS4/EPON 828 laminates.
Influence of Chassis and Driveline Components in Vehicle Frontal Crash
Authors: Saha Nripen K. , Bhojan Rabin 
Published: November 2021

Abstract
With increased focus on new vehicle crash safety, vehicle structures are being developed to sustain more demanding frontal crash conditions such as, offset, angular, and pole impacts. To manage the higher amount of impact energy, vehicle body components are designed for higher strength and stiffness resulting in increased vehicle weight. As an alternative, a more efficient design concept involving the chassis, suspension and driveline components are studied here. Attempts are made to investigate how the non-body structure components of a vehicle can be deployed to absorb crash energy that may lessen the demand on the body-in-white. Contribution of underbody chassis subframe & cross-members, the suspension control arms and the drive-shaft components are evaluated using analytical methods for effective use in frontal impact conditions. Ideas are explored to improve the vehicle crash pulse and reduce passenger compartment intrusions in frontal impacts by employing sub-frame, drive shaft and suspension control arms more effectively.
Safety Aspects Related to the Development of a Full Aluminum Frame for the Year 2000, 1500 Series Chevy Suburban
Authors: Marshaus Julie G. , Gall Mike A. , Topinka Jennifer A. , Bower Glenn R. 
Published: November 2021

Abstract
In conjunction with the FutureTruck collegiate design competition, The University of Wisconsin - Madison has integrated an all aluminum frame into their four-wheel drive, charge sustaining, parallel hybrid-electric sport utility vehicle. The base vehicle is a 2000 Chevrolet Suburban nicknamed the “Moollennium” and weighs approximately 2400 kg. The original GMT 830 frame constitutes 10% of the Suburban’s weight and has the largest weight reduction potential. In a cooperative effort with Tower Automotive, the University of Wisconsin-Madison has modeled, stamped and constructed two full aluminum frames using the GMT 430 tooling. The first frame, the UW 430 AL, was assembled to replicate the GMT 430 frame, while the second-generation frame, the UW 830 AL, mimicked the GMT 830 frame. FEA and traditional deflection and bending calculations were used to stiffen and strengthen the aluminum frame to acceptable levels. Front horn crush tests were used to optimize frontal impact energy absorption — the UW 830 AL design absorbs 36% more energy than the original GMT 430 steel frame with a 40% reduction in peak load. The complete aluminum frame weighs 120 kg — 98 kg lighter than the steel GMT 830 frame and 130 kg lighter than the steel GMT 430 frame.
Crashworthiness Design Optimization of Energy-Absorbing Rails for the Automotive Industry
Authors: Kurtaran Hasan , Omar Tarek , Eskandarian Azim 
Published: November 2021

Abstract
Optimum crashworthiness design of the vehicle rail structure is one of the crucial tasks in designing crashworthy vehicles that render better occupant protection. The usual trial-and-error approach in selecting the optimum design parameters, in order to maximize the energy absorbing capacity of the rail structure, is computationally expensive and cumbersome; particularly when there are several design parameters to be properly selected. Optimization methods can be used to automate the search for the optimum design parameters.
In the current research, an efficient design optimization methodology is presented and utilized to obtain optimum crashworthiness design of the energy-absorbing rail structures. The methodology adopted in this research makes use of Design of Experiments (DOE) based approximation methods, numerical optimization algorithms and structural analysis software. The design optimization approach has been devoted to structural impact applications.
The nonlinear explicit Finite Element (FE) code LS-DYNA was used to conduct the rail impact problems and generate the energy function to be maximized. Several design parameters have been proposed and used to optimize the rail structure. The results indicated the promising capabilities of the developed methodology for design optimization of the energy-absorbing rails in automotive industry.
Structural Topology for Crashworthiness Design by Matching Plastic Strain and Stress Levels
Authors: Soto Ciro A. 
Published: November 2021

Abstract
This paper presents a new formulation for the structural topology optimization problem under crashworthiness conditions. The objective of the optimization problem is to match levels of plastic strain and stress to prescribed values while having a weight constraint under consideration. The problem is solved by using a non-gradient based algorithm that allows to reach near to the optimum in a quick fashion. An example is presented to illustrate the optimization formulation. Results show that the formulation and algorithm are suitable for practical applications.
Functional Design Tree for Mechatronic Projects in Mechanical Engineering Design Course
Authors: Korkmazel Meltem , Erden Abdülkadir 
Published: November 2021

Abstract
The functional approach utilizes a ‘Functional Design Tree’, which is a decomposition hierarchy of functions involving sub-functions of an engineering system at various levels of resolution. Use of functional approach in the design of mechatronic systems is investigated in the senior level mechanical engineering design projects. A survey is conducted on the senior mechanical engineering students after an engineering design course. It is attempted to find out whether the students followed the systematic design approach, and to what extent they used the functional design tree. The results of the survey are presented and evaluated in the paper, and some conclusions are derived for possible outcomes of the survey.
Evaluation of a Failure in a Chlorine Production Facility
Authors: Andrew Stephen P. , Caligiuri Robert D. , Eiselstein Lawrence E. , Parnell T. Kim 
Published: November 2021

Abstract
A process upset at a chlorine production facility resulted in a release that forced the partial evacuation of a nearby town. Investigations revealed that the events commenced with the failure of a shell and tube heat exchanger (liquefier) used to condense chlorine gas. Post-incident inspections revealed a cloth at the liquefier coolant inlet that accelerated the flow in that region, causing certain tubes to be breached. As a result, the water-based brine liquefier coolant was entrained in the chlorine process stream, forming a highly acidic oxidizing mixture. This corrosive mixture then flowed to the chlorine storage tanks destroying an elbow in the tank inlet piping and rendering the tank shut-off tank valve ineffective, thus allowing chlorine to vent into the atmosphere.
This paper discusses the multi-disciplinary approach used to investigate this incident. In particular, this paper discusses the detailed physical inspections performed, the finite element analyses used to determine the flow conditions, and the corrosion testing conducted to evaluate the failure.
Calculation of Nuts Threads Stripping
Authors: Martinez-Martinez Manuel , Ferrand André , Guillot Jean 
Published: November 2021

Abstract
In this article, we describe the development of a precise analytical model allowing to estimate the thread stripping of nuts. Initially, we carried out a modeling by finite elements of the threads stripping using an axisymmetric model and a criterion of rupture by damage. This modeling enabled us to study the various parameters which influence the behavior of a threaded assembly. To do so, we established an experimental design to know the most significant parameters. The result enables us to propose a simple rule for the optimization of the threaded assemblies whatever metallic materials of bolt and nut. We carried out tests of nuts threads stripping in order to validate this model. The estimated results are very close to those obtained by the tests.
Failure Prevention in Fiber Reinforced Composite Materials
Authors: Merodio J. , Sancibrian R. , Viadero F. 
Published: November 2021

Abstract
The study focuses on instabilities for fiber-reinforced nonlinearly elastic solids under plane deformations. The plane of deformation contains the fiber reinforcement. In particular, fiber kinking and fiber debonding instabilities in fiber-reinforced composite materials are examined in terms of the anisotropic character of the material models. The material models consider simultaneously the material anisotropy and the nonlinear performance of the fiber reinforced materials. Fiber kinking is captured under fiber compresion. Fiber debonding is captured under shearing deformations in the fiber direction.
Microtensile Methodology for Mechanical Characterization of Thin Films
Authors: Yeung Betty H. , Lytle Bill , Sarihan Vijay , Read David T. , Guo Yifan 
Published: November 2021

Abstract
A microtensile methodology developed at the National Institute of Standards and Technology (NIST) has been adopted and applied at Motorola to evaluate material properties of thin films. This methodology is a significant part of the materials technology development at Motorola. Special specimens of thin metal films are designed and produced based on common microlithographic techniques and silicon processing methods. The experimentation is performed using the microtensile tester, which was developed for the accurate measurement of constitutive properties of thin metallic films. Through the application of the techniques presented here, valuable information and results have been achieved, which provide an extended information base for thin-film materials. Ultimately, such data are applied to processing and reliability predictions and the optimization of thin-film processes and materials.
New Hybrid Methodology for the Development of MEMS Multivariable Sensors
Authors: Pryputniewicz Emily J. , Angelosanto John P. , Brown Gordon C. , Furlong Cosme , Pryputniewicz Ryszard J. 
Published: November 2021

Abstract
Using recent advances in microelectromechanical systems (MEMS) technology, a new multivariable sensor was developed. This MEMS sensor, capable of measuring temperature, absolute pressure, and differential pressure on a single chip, is particularly suitable for applications in process control industry. However, functional operation of the sensor depends on validation of its performance under specific test conditions. We have developed a hybrid methodology, based on analysis and measurements, that allows such validation. In this paper, the MEMS multivariable sensor is described, the hybrid methodology is outlined, and its use is illustrated with representative results.