bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neowand: A New Device and Paradigms for Immersive Interactions
Authors: Russo Michael , Pimentel Kenneth 
Published: December 2021

Abstract
Natural interactions within immersive environments have been restricted by the limited degree of interaction provided by existing software and mechanical devices for mediating this interface. Furthermore, this interaction has typically depended on techniques that assume 20Hz+ frame-rates. These techniques then suffer from the real-world vagaries of constantly changing frame-rates, and sensor latency that may range from 1Hz to 60Hz. This paper describes both a new set of paradigms for picking, navigating, manipulating and editing objects within an immersive environment and a new device custom-designed for such use. Additionally, this paper describes a technique for ensuring interaction with immersive environments at human-rates (20Hz+) that are independent of scene complexity and most hardware. Finally, this paper describes early results of comparing these new techniques against other practices.
Telemetry-Based Depth Recovery for Virtual Factory Construction and Extension to Remote Facility Management
Authors: Zetu Dan , Banerjee Pat , Akgunduz Ali 
Published: December 2021

Abstract
The fast construction of a Virtual Factory model without using a CAD package can be made possible by using computer vision techniques. In order to create a realistic Virtual Manufacturing environment, especially when such a model has to be created in correlation to an existing facility, a reliable algorithm that extracts 3D models from camera images is needed, and this requires exact knowledge of the camera location when capturing images. In this paper, we describe an approach for depth recovery from 2D images based on tracking a camera within the environment. We also explore the extension of our telemetry-based algorithm to remote facility management, by tracking and synchronizing human motion on the shop floor with motion of an avatar in a Virtual Environment representing the same shop floor.
Evaluation of Some Commercial VR Environments: Trends and Directions
Authors: Hudson A. , Dodds B. , Curtis J. , Banerjee A. , Banerjee P. , DeFanti T. 
Published: December 2021

Abstract
Some of the commercially available software systems for VR applications are evaluated for a number of desired features. These features are useful in determining the choice of software while developing a VR application. The capabilities and drawbacks of the software systems are highlighted using a grading procedure and the current trends and future needs in VR software are discussed.
Design of a Telemanufacturing Test Bed
Authors: Abdel-Malek Layek , Batra Vikram 
Published: December 2021

Abstract
A Telemanufacturing facility has been developed to test virtual manufacturing concepts across the Internet. The essence of this research is a web site/service provider to aid manufacturers, especially small and medium size, in the different production functions of concern. The web site capitalizes on the advances in virtual reality technologies to enable enterprises to gain flexibility and competitiveness. Through this web site companies/users will be able to access a variety of services available within this facility. This web site initially will act as a test bed and a resource center for enterprises to base design and manufacturing decisions as well as utilize technologies available globally. The test bed currently incorporates three facilities, Rapid Prototyping, make or buy decision support system, and manufacturing cell development. Using this facility it will be possible to evaluate the functioning of the Telemanufacturing infrastructure and also highlight the problems and deficiencies associated with the system.
Interactive Product Simulation Environment for Assessing Assembly and Maintainability Tasks
Authors: Fernando Terrence , Wimalaratne Prasad , Tan Kevin , Murray Norman 
Published: December 2021

Abstract
This paper presents the design and implementation of an interactive product simulation environment for supporting interactive assembly and maintenance tasks. The system architecture of the constraint-based virtual environment is based on the integration of components such as OpenGL Optimizer, Parasolid geometric kernel, a Constraint Engine, an Assembly Relationship Graph (ARG) and a task model. The approach presented in this paper is based on pure geometric constraints. Techniques such as automatic constraint recognition, constraint satisfaction, constraint management and constrained motion are employed to support interactive assembly operations and realistic behaviour of assembly parts. The user inputs are handled using a task model based on Augmented Transition Networks (ATN). The current system has been evaluated using two industrial case studies.
Analyzing Industrial Furnace Efficiency Using Comparative Visualization in a Virtual Reality Environment
Authors: Freitag Lori , Urness Tim 
Published: December 2021

Abstract
We describe an interactive toolkit used to perform comparative analysis of two or more data sets arising from numerical simulations. Several techniques have been incorporated into this toolkit, including (1) successive visualization of individual data sets, (2) data comparison techniques such as computation and visualization of the differences between data sets, and (3) image comparison methods such as scalar field height profiles plotted in a common coordinate system. We describe each technique in detail and show example usage in an industrial application aimed at designing an efficient, low-NOx burner for industrial furnaces. Critical insights are obtained by interactively adjusted color maps, data culling, and data manipulation. New paradigms for scaling small values in the data comparison technique are described. The display device used for this application was the CAVE virtual reality theater, and we describe the user interface to the visualization toolkit and the benefits of immersive 3D visualization for comparative analysis.
Effect of Large Structural Perturbations on Response of Structural-Acoustic Systems
Authors: Hahn Steven R. , Ferri Aldo A. 
Published: December 2021

Abstract
Due to high sensitivity, first-order perturbation analysis of structural-acoustic systems can be inaccurate for large perturbations. Using high-order derivatives to create a Taylor series approximation for the perturbed solution can result in slow convergence or even divergence. A rational polynomial or Padé approximation may overcome the poor convergence of the Taylor series by canceling out the poles causing the poor convergence. In this study, a finite element framework is used to describe the structural-acoustic system. External radiation and scattering problems are accommodated by truncating the infinite fluid region using exponential decay infinite elements. Changes to a nominal model are introduced through a structural perturbation to the nominal structural stiffness and/or mass matrices. An efficient method for calculating the solution derivatives with respect to the structural perturbation is presented. A Taylor series expansion is constructed using the derivative information and the convergence criteria for the series is examined. The local solution and derivatives are then used to construct a Padé approximation. The method is illustrated by considering what effect the addition of a rib stiffener to a plate in a rigid baffle has on the scattering of a plane wave. The approximation is shown to be quite accurate for large perturbations even when there are one or more nearby poles and the Taylor series fails to converge.
Acoustic Radiation by Point- or Line-Excited Laminated Plates
Authors: Hwang Y. F. , Kim M. , Zoccola P. J. 
Published: December 2021

Abstract
This paper presents an elasticity theory solution for computation of acoustic radiation by a point- or line-excited fluid-loaded laminated plate, which may consist of a stack of an arbitrary number of different isotropic material layers. A one-side water-loaded three-layer sandwich plate, which consists of a hard rubber core sandwiched between two steel plates of equal thickness, was used as an example of the laminated plates. The approximated equivalent sandwich plate solutions were compared with the elasticity theory solutions. These results show that the approximated solutions are, as expected, valid only at frequencies much lower than the coincidence frequency. The numerical result also shows that, even at about one-tenth of the coincidence frequency, the approximated solutions suffer substantial error. The differences between the dry-side- and the wet-side-excited radiated fields of a single-layer uniform plate and a sandwich plate were investigated and compared, and found to be significantly different at frequencies above the coincidence frequency.
Treatment of Damping in Structural Redesign by Large Admissible Perturbations
Authors: Blouin Vincent 
Published: December 2021

Abstract
A method to solve redesign (inverse design) problems of complex structures with forced response amplitude constraints is developed. It is assumed that a structure is excited by harmonic external forces at a given frequency. The problem is to find optimum values of structural characteristics in order to achieve a desired level of forced response at one or several locations on the structure. The method of LargE Admissible Perturbations (LEAP) is used. Damping is shown to have an important impact on the redesign solution and must be considered in the redesign process. Two different treatments of the damping, leading to two different algorithms, are studied. In the case of structural damping, the commonly used Rayleigh formulation allows the damping matrix to be diagonalized by use of the real mode shapes of the undamped structure. This leads to the derivation of an exact perturbation equation with no loss of accuracy. When damping cannot be approximated by the Rayleigh model, the damping matrix must be treated externally and the perturbation equation is solved by means of an iterative process introduced into the redesign algorithm. The two algorithms are compared in terms of accuracy and limitations.
Design Optimization Process for Minimizing High Frequency Vibration Based on an Energy Finite Element Formulation
Authors: Borlase George , Vlahopoulos Nickolas 
Published: December 2021

Abstract
The Energy Finite Element Analysis (EFEA) offers an alternative solution to the established Statistical Energy Analysis (SEA) for simulating the vibration of large scale structures. A brief theoretical overview and comparison of the two methods is presented first. Numerical models for a fishing boat are utilized for a comparison between the two formulations. In order to demonstrate the powerful capabilities of EFEA in the area of simulation based design, an optimization routine is integrated with an EFEA solver. The optimized distribution of damping over the hull of a vessel is computed. The formulation of the optimization process is presented. The definition of the design variables, the objective function, and the constraints is discussed. The flow chart of the optimization process, and a comparison between the initial and the optimized design are presented.
A New Design Feature to Improve the Sound and Efficiency of Automotive HVAC Centrifugal Blower Systems
Authors: Botros Monier B. , Hanna Dorothy F. , Nava Tony (J) , Lai Ming-Chia 
Published: December 2021

Abstract
A new apparatus is developed to control the airflow field at the inlet of a centrifugal blower system. The new apparatus has desirable effects on the flow and noise performance of an HVAC air-handling system. The apparatus design parameters are defined, and are investigated using the design-of-experiments techniques. Experimental airflow and sound pressure levels data are used to screen and evaluate the apparatus design parameters. The effects of two parameters and their interaction on the overall sound pressure levels and discrete tones, sound quality, are defined to aid in optimizing the design.
The apparatus controls the flow field to increase the effectiveness of the blower fan, and to minimize the energy losses and air-rush noise. Its effect on the air velocity in the radial direction of a centrifugal fan is investigated by Laser Doppler velocity measurements (LDV). Other relationships with the centrifugal fan design parameters are described and illustrated by LDV and computational fluid dynamic (CFD) analysis.
The advantages of the apparatus include the reduction of air-handling system SPL by 1–3dBA (2–6%) and power consumption by (7–15%) through energy conservation, with minimal change in the system airflow rate.
Prediction of Automotive Hydrobushing Resonant Frequency
Authors: Lu Min , Ari-Gur Judah , Garety John 
Published: December 2021

Abstract
The success of hydromounts in vehicle vibration isolation during the past decade and a half has stimulated automotive engineers to apply the similar mechanism to bushing design. A typical conventional bushing is comprised of a rubber section enclosed by an inner and an outer metal, while a bushing filled with internal fluid is called a hydrobushing. Based on the fact that the fluid inside the hydrobushing generates the majority of the damping, the mathematical model of the hydrobushing used in this paper neglects the rubber damping effect to the system. The equations of fluid motion and conservation and system equilibrium equation determine its resonant frequency. The conclusion is that the resonant frequency is proportional to the ratio of the cross sectional area of the inertia track to the equivalent piston area and the square root of volumetric stiffness; and it is inversely proportional to the square root of the mass of the fluid in the inertia track. The predicted resonant frequency correlates well with the tested results.
Wave Reflection/Transmission Analysis of Thick Multi-Layered Structures Using the Numerical Truncation Approximation for the Transfer Matrix Technique
Authors: Balasubramaniam Krishnan 
Published: December 2021

Abstract
In this paper, the authors describe a numerical truncation technique for handling the numerical instability problems associated with the utilization of the transfer matrix method. This, rather simplistic modification to the numerical coding extends the transfer matrix method to a wide range of applications.
Automatic Procedure for Automating the Analyzer Window Setting for Transient Vibration Data Capture
Authors: Ratcliffe Colin P. , Crane Roger M. 
Published: December 2021

Abstract
When conducting experimental vibration tests on composite structures, one of the most important settings in the spectrum analyzer is the window function. This setting effects the performance of the Fourier analyzer, and can change the observed energy dissipation of the structure. For impact excitation techniques the window used for transient response signals is typically an exponential function. Traditionally, the window setting is chosen by what “looks right.” Too little windowing introduces errors during the Fourier transforms; too much degrades the signal. This paper presents an automatic procedure for optimizing the exponential window function when measuring transient, decaying signals. Initially, the natural attenuation of a signal is automatically determined, and this attenuation is then used to determine the optimum window parameters. The theory is developed for a single-degree-of-freedom system and demonstrated for theoretical and experimental multi-modal structures with poor signal-to-noise ratios. In all cases it is shown that the computationally inexpensive optimization procedure is highly satisfactory. There is also a side benefit in that almost identical numerical procedures can be used to automate the logarithmic decrement technique of estimating structural damping.
Numerical Solution of the Equations Governing the Steady State of a Thin Cylindrical Web Supported by an Air Cushion
Authors: Müftü Sinan 
Published: December 2021

Abstract
The numerical method used to solve the coupled nonlinear, partial differential equations (PDEs) representing the interaction between a thin, flexible, cylindrical web and an air cushion at steady state is analyzed. The web deflections are modeled by a cylindrical shell theory that allows moderately large deflections. The airflow is modeled in two-dimensions with a modified form of the Navier-Stokes and mass balance equations that have non-linear source terms. The coupled fluid/structure system is solved numerically in a stacked iteration scheme: The fluid equations are solved using pseudo-compressibility method with artificial viscosity; and the web equations are solved with a modified Newton-Raphson method. The convergence characteristics of the coupled system and the effects of the numerical parameters on the steady state solution are studied by numerical experiments.
The Sound Transmission Through a Baffled, Thin, Finite, Elastic Plate by Using Boundary Integral Equations
Authors: Kawai Yasuhito 
Published: December 2021

Abstract
The prediction of sound transmission through a thin elastic plate such as a window is an important problem in the field of noise control engineering. Integral equations which express sound fields in infinite half spaces which are divided off by the baffle and the elastic plate are introduced and combined with the equation of plate vibration to solve as a coupled system. The image method is used in every equation to reduce unknown functions and boundaries which should be considered. Some numerical examples are solved numerically to examine the method.
Modification of Resonance-Induced Sound by the Configuration of a Slotted Tube
Authors: Seto Kunisato , Lee Dong-Hoon , Xu Zhi Xiang 
Published: December 2021

Abstract
A slotted tube is a device to reduce flow-induced noise. In order to understand the noise reduction mechanism of the tube, an experiment has been systematically performed. Noise measurements have been carried out for a variety of slot dimensions such as the length, the width, the thickness and the number of slots. In the case of a significantly long slot, a discrete tone is observed under comparatively lower pressure conditions. Three mechanisms of sound generation concerning the slotted tube have been clarified.
Acoustic Radiation Models of Brake Systems From Stationary LDV Measurements
Authors: McDaniel J. Gregory , Moore James , Chen Shih-Emn , Clarke Cory L. 
Published: December 2021

Abstract
This paper presents a study of the acoustic radiation from a stationary brake system that was conducted in order to better understand the acoustic radiation from squealing brake systems. A large class of squeal mechanisms are associated with the resonant behavior of an operating brake system. In this work, an analysis is presented that equates the natural frequencies and modes of a mechanically-excited stationary brake system to those of an operating brake system. The equivalence allows one to conduct experiments on stationary brake systems in order to gain insight into the acoustic radiation mechanisms of squealing systems, which is a substantial convenience given the difficulty of artificially inducing squeal. The methodology is applied to scanning LDV measurements of the normal velocity of a shaker-excited stationary brake system. Acoustic radiation efficiencies and intensities of the modes were computed by importing the experimentally measured velocities into a BEM software package. These efficiencies approach unity at a coincidence frequency defined by comparing acoustic wavelengths to the wavelengths of flexural waves that propagate circumferentially around the rotor. For the particular system tested, this remarkably high radiation efficiency occurred at frequencies above 2–3 kHz.
Asymptotic and Exact Radiation Boundary Conditions for Time-Dependent Scattering
Authors: Thompson Lonny L. , Huan Runnong 
Published: December 2021

Abstract
Asymptotic and exact local radiation boundary conditions first derived by Hagstrom and Hariharan are reformulated as an auxiliary Cauchy problem for linear first-order systems of ordinary equations on the boundary for each harmonic on a circle or sphere in two- or three-dimensions, respectively. With this reformulation, the resulting radiation boundary condition involves first-order derivatives only and can be computed efficiently and concurrently with standard semi-discrete finite element methods for the near-field solution without changing the banded/sparse structure of the finite element equations. In 3D, with the number of equations in the Cauchy problem equal to the mode number, this reformulation is exact. If fewer equations are used, then the boundary conditions form uniform asymptotic approximations to the exact condition. Furthermore, using this approach, we formulate accurate radiation boundary conditions for the two-dimensional unbounded problem on a circle. Numerical studies of time-dependent radiation and scattering are performed to assess the accuracy and convergence properties of the boundary conditions when implemented in the finite element method. The results demonstrate that the new formulation has dramatically improved accuracy and efficiency for time domain simulations compared to standard boundary treatments.
Influence of Support Compliance and Residual Stress on the Shape of Doubly-Supported Surface-Micromachined Beams
Authors: Kobrinsky Mauro J. , Deutsch Erik R. , Senturia Stephen D. 
Published: December 2021

Abstract
Doubly-supported surface-micromachined beams are increasingly used to study the mechanical properties of thin films. Residual stresses in the beams cause significant vertical deflections, which affect the performance of these devices. We present here both experimental results for doubly-supported polysilicon surface-micromachined beams, and an elastic model of the devices that takes into account the compliance of the supports and the geometrical non-linear dependence of the vertical deflections on the stress in the beam. An elastic one-dimensional model was used for the beams, and the response of the supports to forces and moments was obtained using Finite Element Method simulations. The model explains a previously observed gradual increase of the maximum vertical deflections of the beams with increasing length at a given constant residual stress, and, in agreement with experimental observations, predicts two stable states for compressively stressed beams: one with the beam bent up, the other down.
Three-Dimensional Modeling of Solder Shape for the Design of Solder Self-Assembled Micro-Electro-Mechanical Systems
Authors: Kladitis Paul E. , Harsh Kevin F. , Bright Victor M. , Lee Y. C. 
Published: December 2021

Abstract
Micro-electro-mechanical systems (MEMS) can be assembled by harnessing the surface tension of liquid solder. In order to assemble the MEMS to precise positions, the shape of the solder, of a given volume, must be known. This paper presents two methods of modeling the shape of solder wetted between two MEMS plates. One method accurately models the solder shape by finding the minimum surface energy shape. A second, less accurate but faster, method approximates the solder shape using simple geometric shapes. The geometric shape model can be trained to be just as accurate as the minimum surface energy model.
Localized Deposition of Polysilicon for MEMS Post-Fabrication Processing
Authors: Joachim Daphne , Lin Liwei 
Published: December 2021

Abstract
In this paper, the localized deposition of polysilicon is demonstrated on suspended and attached microbeams. The microbeams are 1, 2 and 5μm wide; 0.5, 1.5 and 2μm thick; and 50 and 100 μm long. Polysilicon is deposited by thermal decomposition of silane gas on the electrically-heated structures. The peak temperature of each microbeam is estimated using finite element analysis and an electro-thermal analysis is discussed. The deposited silicon is amorphous or polycrystalline, depending on the process conditions. The deposition rates are much higher than those of conventional LPCVD polysilicon. Localized polysilicon deposition is useful in MEMS post-fabrication processes such as tuning resonators and sealing packages.