bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geometrical Non-Linear Periodic Vibration of Plates
Authors: Petyt M. , Ribeiro P. 
Published: November 2021

Abstract
Periodic, geometrically non-linear free and steady-state forced vibrations of fully clamped plates are investigated. The hierarchical finite element method (HFEM) and the harmonic balance method are used to derive the equations of motion in the frequency domain, which are solved by a continuation method. It is demonstrated that the HFEM requires far fewer degrees of freedom than the h-version of the FEM. Internal resonances due to modal coupling between modes with resonance frequencies related by a rational number, are discovered. In free vibration, internal resonances cause a very significant variation of the mode shape during the period of vibration. A similar behaviour is observed in steady-state forced vibration. The stability of the steady-state solutions is studied by Floquet’s theory and it is shown that stable multi-modal solutions occur.
View Through the Door of the Sofia Project by a Reliability Engineer
Authors: Frank Michael V. 
Published: November 2021

Abstract
The National Aeronautics and Space Administration (NASA) and Deutsches Zentrum Für Luft- und Raumfahrt (DLR) e. V. are working together to create a Stratospheric Observatory for Infrared Astronomy (SOFIA). One of the key elements of the modification of the Boeing 747-SP aircraft to be used is a new door system that both protects the infrared telescope during flight by covering the aircraft cavity within which the telescope resides and following the telescopes motion to provided an unvignetted view of the sky. The intentions of this paper are: describe the value added by a productive interaction of reliability engineering with the integrated product design team at NASA Ames Research Center which is responsible for design of this “cavity door” system; to point out key reliability improvement strategies applied to the cavity door system; and to offer a few principles to guide interaction of reliability engineers with a design team.
Knowledge Transfer for Emerging Work Paradigms
Authors: Sturdivant Maggie , Carnes Earl 
Published: November 2021

Abstract
Department of Energy (DOE) missions include scientific research and development, nuclear weapons stockpile stewardship, and cleanup of the environmental legacy from weapons production. Since the cold war’s end, changes in mission focus have placed considerable attention on the standards for performing work. For activities where risk is understood, the work force’s collective experience is codified in standards. For activities with unconventional risks, good practices and individual experience communicate what is known at the edge of technology and consensus Standards. This paper describes the basis for a Procedures standard, a principles-based enterprise approach for knowledge transfer that supports the unique missions of DOE.
Web-Based Risk and Hazard Identification and Screening
Authors: Steele John L. , Bonano Evaristo J. 
Published: November 2021

Abstract
Organizations, both in the private and public sector, need to avoid to the extent practicable, workplace hazards and minimize the associated risks in order to comply with regulations. However, they have also recognized that this is a sound business practice that could result in significant cost savings by avoiding fines and penalties due to non-compliance and enhanced productivity. Consequently, many organizations have instituted safe work practices into their operations and those practices have become a major criterion in evaluating managers’ performance. This new philosophy is now commonly referred to as “Integrated Safety Management.”
Per the direction of the Secretary of Energy, all U. S. Department of Energy (“DOE”) facilities across the country have been instructed to implement an Integrated Safety Management System. Different DOE facilities have taken various approaches to the implementation of the system.
This paper describes the approach instituted at Sandia National Laboratories and a tool that was developed from lessons learned during that effort. The tool is the cornerstone for implementing an Integrated Safety Management System in a time and cost-effective manner. The tool is now commercially available and can be readily rendered applicable to any type of systematic assessment process.
Integration of Safety, Health, and Ergonomic Issues Into the Undergraduate Mechanical Engineering Curriculum
Authors: Bloswick Donald S. , Elliott Charles B. , Jones Kimberli 
Published: November 2021

Abstract
Course modules which include an introduction to safety, health and environmental issues and concerns are being developed for the undergraduate mechanical engineering curriculum. In addition a reference matrix is being prepared which includes list of available problem sets and case studies cross referenced to relevant undergraduate mechanical engineering courses. This information will be made available in electronic and web-based format for interested parties.
Semantic Knowledge for Manufacturing Systems
Authors: Tsourikov Val , Batchilo Leo , Devoino Igor 
Published: November 2021

Abstract
The process of extracting technical knowledge from the text of documents is considered. The results are represented as Subject-Action-Object (SAO) concepts. The SAOs are used for searching large databases and organizing relevant knowledge in problem-solution format (www.cobrain.com), for automatically building function models from documents, for revealing cause-effect relationships from the text and for other applications. As a result, the manufacturing processes can be improved and optimized.
RF-Switches in MEMS Technology for the Integration in Communication Applications
Authors: Michaelis Sven , Ploetz Florian , Aigner Robert , Timme Hans-Joerg , Binder Josef , Noe Reinhold 
Published: November 2021

Abstract
A new type of rf-switch for use in communication applications is presented in this paper. These switches can be used for purposes such as antenna selection (transmitter / receiver) or for the filter-path selection in multi-band communication systems.
The design of the switch is based on a torsion-type model with two switch contacts for a dual-mode switching operation. The mechanical operation is performed by electrostatic actuation with switching voltages in the range of 10V. The device is manufactured in a standard CMOS production line with a specialized micromachining process.
Initial samples of the switch have been tested successfully.
A Hybrid Pneumatic/Electrostatic Milli-Actuator
Authors: Chiang Kenneth H. , Fearing Ronald S. 
Published: November 2021

Abstract
In typical MEMS applications, actuation is accomplished directly by converting electrical input power to useful mechanical power. However, indirect schemes employing electrically driven primary and alternately driven secondary actuators can trade simplicity and bandwidth for lower forces and strokes in the primary actuator, hence reducing power consumption.
Because it is generally easier to build actuators with high force and low stroke, we propose a hybrid actuator with a pneumatic oscillator as the secondary and an electrostatic clamp as the primary. By clamping the oscillator at its extremes of travel, the hybrid actuator can be turned on and off.
In this paper, we report on progress towards fabricating such a hybrid actuator. We have demonstrated operation of a 40×40×30 mm3 oscillator at 6 Hz with a stroke of 2.5 mm and a peak force of 1.1 N, although fabrication of the electrostatic clamp has not been accomplished.
Residual Stress Effect on Performance of Diaphragm-Based MEMS Pressure Transducers
Authors: Niu Meng-Nian , Kim Eun Sok 
Published: November 2021

Abstract
We experimentally and theoretically confirm that residual stress within a diaphragm is critical in limiting the performance of diaphragm-based piezoelectric microphones even if the stress is low (around 50 MPa). We have fabricated and studied microphones with Al/parylene/ZnO/SiN2/poly-Si/SiN1 (from top to bottom) diaphragm. As the SiN1 supporting layer is removed layer by layer from the backside with CF4 plasma (in an RIE system), we measure both the sensitivity and center displacement of the microphone before and after each RIE etching of the SiN1 from the microphone diaphragm, and find the sensitivity increasing about 5–16 times with the best sensitivity reaching 11 μV/μbar from a mere 0.6 μV/μbar. The center displacement increases very moderately as the SiN1 layer thickness decreases from 0.8 to 0.2 μm. However, the center displacement starts to increase greatly as the SiN1 layer thickness goes below 0.2 μm, which compares with our theoretical analysis well. In the case of the SiN1 layer having compressive residual stress, the compressive stress can enhance the microphone sensitivity and center displacement to a certain extent.
Silicon Micromachined Fiber-Optic Pressure Sensor
Authors: Vujanic Aleksandar , Adamovic Nadja 
Published: November 2021

Abstract
In this paper, we present a fiber optic pressure sensor capable for operation in critical environments. Special attention is given to the sensor design, so that the sensor fabrication is as simple as possible and can be accomplished using standard micromachining processes (wet etching of silicon). Presented pressure sensor employs the principle of light intensity modulation induced by bending of a membrane with boss. Under the influence of pressure a sidewall of boss screens certain area of the fiber-end and modulates the reflected optical signal.
A number of design specialties and novel ideas for overcoming the limitations of standard wet etching of silicon are presented. The used fabrication procedure enables, with slight modification of the etching time, fabrication of sensors applicable for measuring various pressure ranges.
Design, Modeling, and Testing of Micromachined Piezoelectric Clamped-Clamped Beam Resonators
Authors: Piekarski Brett , DeVoe Don L. , Kaul Roger , Dubey Madan 
Published: November 2021

Abstract
The design, modeling, and performance of suspended piezoelectric clamped-clamped single-beam micro electro mechanical system (MEMS) resonators is reported. Resonators with frequencies between 171 kHz and 9.2 MHz have been fabricated, tested and compared to finite element and exact solution models. Resonator designs vary from 6- to 20-μm wide and 25- to 400-μm long. A model describing the electromechanical performance of the resonators is presented. Operation is demonstrated from a vacuum pressure of 20-mTorr to atmospheric with drive voltages as low as 2.5 mV and a dynamic range of greater than 40 dB. Devices exhibit loaded quality factors (Qs) greater than 1000 at a vacuum pressure of 20-mTorr.
Anodic Alumina MEMS: Applications and Devices
Authors: Govyadinov Alexander , Mardilovich Peter , Novogradecz Kathy , Hooker Stephanie , Routkevitch Dmitri 
Published: November 2021

Abstract
Hybrid micromachining of anodic alumina films was shown to be a promising technology for creating ceramic MEMS for harsh application environments. By combining features of both bulk and surface micromachining, this technology offers flexibility in design and tremendous application opportunities. This paper will overview the authors’ work on application development of micromachined anodic alumina, with the main focus on gas microsensors, vacuum microelectronics, and high aspect ratio MEMS.
Measurement and Modeling of the Flow Characteristics of Micro Disc Valves
Authors: Carretero J. A. , Breuer K. S. 
Published: November 2021

Abstract
The head losses in microfluidic systems such as micropumps are dominated by losses in microvalves, where microfabrication constraints limit significantly possible microvalve designs. This makes them quite different from conventional valves. In particular, flow characteristics in the laminar and low-Reynolds turbulent regimes are not understood clearly, and detailed information about the flow losses is lacking. This paper addresses this issue by using a scaled-up (10:1) valve experiment to measure pressure losses in typical microfabricated valve geometries. The macroscale model is fully instrumented and discharge coefficients and sensitivities to stroke, seat width and Reynolds number are presented.
A Study on the Interaction Force Between Two Small Bodies on a Liquid for Micro Self Assembly and Separation
Authors: Saif Taher 
Published: November 2021

Abstract
The paper presents a detailed study of the mechanism by which a MEMS plate forms a meniscus with a liquid, and the corresponding solid-liquid interaction force. The study is than extended to investigate the interaction force between two small thin plates forming meniscii with a liquid. It is shown that the force is attractive for similar meniscii and repulsive for opposite meniscii. If the meniscii are of the same type but not identical (e.g., one solid makes a steeper meniscus than the other) then the force is attractive at long distances, repulsive at shorter distances, with a stable equilibrium at a finite distance between the solids. The study reveals that MEMS (hydrophilic or phobic) can probe objects in a liquid without inundating themselves. Furthermore, capillary forces can be harnessed to self assemble or separate small solids (micro chips or living cells) on a liquid surface non-invasively.
Design and Analysis of a Preconcentrator for the μChemLab™
Authors: Wong C. Channy , Flemming Jeb H. , Manginell Ronald P. , Kottenstette Richard J. , Frye-Mason Gregory C. 
Published: November 2021

Abstract
Preconcentration is a critical analytical procedure when designing a microsystem for trace chemical detection, because it can purify a sample mixture and boost the small analyte concentration to a much higher level allowing a better analysis. This paper describes the development of a micro-fabricated planar preconcentrator for the μChemLab™ at Sandia. To guide the design, an analytical model to predict the analyte transport, adsorption and desorption process in the preconcentrator has been developed. Experiments have also been conducted to analyze the adsorption and desorption process and to validate the model. This combined effort of modeling, simulation, and testing has led us to build a reliable, efficient preconcentrator with good performance.
Atomistic and Continuum Computational Approaches at NRL for MEMS Device Analysis
Authors: Sandberg William C. 
Published: November 2021

Abstract
The computational approaches needed for analysis of the operation of MEMS devices can include quantum mechanical methods, atomistic molecular dynamics (MD) methods, molecular mechanics (MM), Direct Simulation Monte Carlo (DSMC), continuum fluid and solid mechanics, and on up to parametric representations. The length and time scales of the phenomena being studied dictates the selection of the appropriate computational approach, or, in some cases, the combination of approaches. A number of these computational approaches are being applied at the Naval Research Laboratory to analyze the performance of a variety of MEMS devices. Examples of a number of specific MEMS component analyses that have been carried out are discussed. Possible future applications for the MEMS computational technology are also presented.
Behavior of a MOEMS Package (TI DMD™) Under Mechanical and Thermal Loads
Authors: Variyam Manjula N. 
Published: November 2021

Abstract
The Digital Micromirror Device (DMD™), developed by Texas Instruments is a key player in the digital projection arena. The packaging requirements of this device are different from those of standard integrated circuits. The current paper focuses on understanding the DMD™ package structural behavior under thermal and mechanical loads through finite element modeling. Package stress conditions were quantified using a metric that accounted for both peel and shear stress. Analysis showed that the package was highly sensitive to mechanical load magnitude and distribution. The results identified dominant failure modes and provided direction for developing new design verification tests needed to qualify the package design.
Prototyping and Testing Methods for Electrostriction of Actuators for a Mesoscale Compressor
Authors: Trujillo R. , Mou J. , Phelan P. E. , Chau D. S. 
Published: November 2021

Abstract
A design of a prototype mesoscale compressor using electrostriction of polymers as a way of actuation is described. In this application, electrostrictive polymers (EP) are squeezed and stretched by electrostatic forces generated by a high voltage applied via thin-film Au electrodes. This paper compares the results of several experiments performed on silicone materials based on Dow Corning Sylgard 182 and 184. The silicone films are prepared by mixing Sylgard 182 or 184 with curing agents in a weight ratio of 10:1. Some samples are tested in a flat configuration, while others are rolled together to form a tube actuator. This actuator is placed inside a glass tube and sealed on one end to form a mesoscale compressor. The tests on electrode thickness show that the thinner the electrode, the greater the displacement. Greater strain can be achieved by making thinner silicone films. The pressure achieved is only on the order of 1 kPa, but significantly greater pressures are anticipated if sealing losses can be reduced.
A User’s Perspective: Packaging Achieves Test Affordability
Authors: Liu Wayne P. 
Published: November 2021

Abstract
Sensor performance and cost are typically the main features reviewed by potential users of MEMS sensor applications. However with more options becoming available, experienced users will begin to consider more than just performance and hardware cost and will seek packaging features which reduce the effort needed to set up, calibrate and successfully operate MEMS sensor systems. A reduction in the cost of effort needed to collect good data will impact test affordability. Data from MEMS shear stress testing on cylinder boundary layer and separation bubble features will be presented to show how packaging can affect both performance and affordability. Manufacturers should ask: What is remembered the most at the conclusion of a MEMS application, the cost of hardware or the cost of effort required to collect good data?
Program Assessment: Equivalency and Credentials for the Global Marketplace
Authors: Phillips Winfred M. 
Published: November 2021

Abstract
Great engineering achievements, from the Aqueducts of Rome and Hausman’s Sewer System for Paris to the Boeing 757 and the Space Shuttle, have always benefitted from international influence and content. The reliability of engineering structures and systems has always engendered the confidence of international users. U.S. citizens drive European automobiles with confidence and Europeans drive across U.S. bridges without pause. Today, international content is extensive, often formalized and regulated and a permanent part of tomorrow’s engineering. Engineers both participate in their profession worldwide and evaluate and accommodate international content at home. Multinational companies demand multinational engineering practice. “Credentials without borders” is desired. Accreditation is key to quality assurance.
Constitutive Modeling of Multiaxial Deformation and Induced Anisotropy in Superplastic Materials
Authors: Khraisheh Marwan K. 
Published: November 2021

Abstract
The multiaxial deformation of superplastic materials is modeled within a continuum theory of viscoplasticity using a generalized anisotropic dynamic yield function. The anisotropic dynamic yield function is capable of describing the evolution of the initial anisotropic state of the yield potential through the evolution of unit vectors defining the direction of anisotropy. The evolution of the direction of anisotropy is represented by a constitutive spin such that initially it is identical to the Eulerian spin and as deformation continues, it tends towards an orthotropic spin. Experiments on the model Pb-Sn alloy were conducted and used to calibrate and verify the constructed model. It is shown that the model in conjunction with the anisotropic dynamic yield function is capable of predicting the actual trend of the induced axial stresses recorded in fixed-end torsion experiments.
Using Modeling and Simulation to Evaluate Traction of Track Vehicles
Authors: Gunter David D. , Letherwood Michael D. 
Published: November 2021

Abstract
The US Army Tank-automotive and Armaments Command (TACOM) has the mission of procuring and managing the US Army’s fleet of wheeled and tracked vehicles. TACOM’s Tank Automotive Research, Development and Engineering Center (TARDEC) provides engineering and scientific support directed at maximizing the capability of all Department of Defense (DOD) ground vehicle systems and ensuring the safety of their personnel.
In order to reduce the time required to deploy troops and equipment, engineers and scientists at TARDEC have been investigating modifications to ground vehicles that lead to overall increases in performance, especially in the areas of off-road mobility, and on-road stability and handling. This paper describes an effort to assess the dynamic performance of a track laying (tracked) Recovery Vehicle towing a disabled tracked vehicle whose weight is approximately equal to that of the Recovery Vehicle. Specifically, this paper will describe techniques employed to develop a 3-dimensional dynamic model of the vehicle combination, and apply the model to evaluate towing performance of the recovery vehicle. It also describes measures aimed at minimizing incidences of jackknifing when braking on downhill slopes, as well as vehicle design modifications that were modeled and simulated in efforts to reduce the combination’s jackknife vulnerability. These modifications included tow bar schemes that locked-out inter-vehicle yaw, and external surge brakes mounted on the towed vehicle. Techniques used to model and simulate the tractive effort available to the Recovery Vehicle on varied soil types are described as are analyses used to determine the combination’s ability to climb grades. Vehicle modifications aimed at increasing the tractive effort available, such as tow bar pitch orientation and track shoe geometry changes are also described.
Twisting Moment of a Non-Rolling Tire
Authors: Gofron Marian 
Published: November 2021

Abstract
The steering system is a key element in the determination of vehicle performance. The steering force of a vehicle depends upon the steering system geometry and the interaction between the tires and the ground. Maximum steering force usually occurs when the vehicle is not moving and an attempt is made to steer the wheels lock to lock. During the process of designing a steering system, the steering force is often determined by laboratory experiments or simple calculations. This paper presents formulas that can be used to determine tire-twisting moment when the tire is not rotating. The formula considers the elastic and the frictional effect of the tire, the effect of steering direction, and footprint size on the tire twisting moment. A computer program utilizing these formulas can be written to determine the steering force for any steering linkage member for a stationary vehicle.