bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anomalous Transition to Turbulence in Microtubes
Authors: Sharp Kendra V. , Adrian Ronald J. , Beebe David J. 
Published: November 2021

Abstract
As the microfluidics field expands, required flowrates in microdevices are expected to span a large range of Reynolds numbers (Re), and the prediction of flow regime, namely laminar versus turbulent, is highly relevant. Recent measurements have been inconclusive in answering a fundamental question: Does microscale flow behave differently than macroscale flow? Previous measurements have suggested that the transition to turbulence occurs at Re much lower than 2000, the generally accepted lower limit of macroscale transition to turbulence. The current experiments use both bulk flow resistance measurements and micro-Particle Image Velocimetry (micro-PIV) results to show that, for Re &lt; 1100–1500 and microchannel diameters 75 to 250 μm, the velocity profiles and flow resistance are well-predicted by macroscale laminar flow theory. For Re &gt; 1100–1500, an initial departure from laminar behavior is noted both from the flow resistance and the micro-PIV experiments. Thus, some “micro-scale” effects are observed, though they are not as dramatic as those observed in previous studies. A brief literature review of transitional macroscale pipe flow is presented, and potential explanations are proposed for the possible “micro-scale” effects observed in these experiments.
Microchannels in Series With Gradual Contraction/Expansion
Authors: Lee Wing Yin , Lee Sylvanus Yuk Kwan , Wong Man , Zohar Yitshak 
Published: November 2021

Abstract
Fluidic systems usually contain multiple channels connected together, and the blood system or the lungs are typical examples. Microdevices consisting of a pair of microchannels in series, integrated with pressure sensors, were fabricated to study fluid flow in such complex microsystems. The dimensions of the channels are about 40μm×1.2μm×2000μm for the wide channel and about 20μm×1.2μm×2000μm for the narrow one. The channels are connected via an expansion/contraction section with an included angle of either 15° or 90°. Nitrogen was passed through the micro devices under inlet pressures up to 50psi. Each device was tested in the expansion, flow from narrow to wide channel, and contraction mode, flow from wide to narrow channel. Mass flow rate was first measured as a function of the overall pressure drop. Then the detailed pressure distribution along the channels was measured to understand the flow pattern around the expansion/contraction section. The reduced Reynolds number for such flows is about 0.001, suggesting that the flow is of the Hele-Shaw type with no separation. However, our results show that the flow resistance is higher than the friction losses, indicating that the flow may separate at the transition between the channels, and the added resistance due to the separated flow is not negligible although the channels are very long.
Fabrication and Packaging of Microfluidic Devices With SU-8 Epoxy
Authors: Kuan N. , Liepmann D. , Pisano A. P. 
Published: November 2021

Abstract
Sealed fluidic microchannels were fabricated from SU-8 epoxy, sandwiched between glass and silicon substrates. The process flow for fabricating microfluidic devices, including packaging, is described. Features integrated in the packaged device include sealed channels, electrical circuits, membrane for thermal isolation and pressure sensing, as well as interconnects for fluids and electrical signal. The resulting channel is optically transparent from all sides. The objective is to introduce a new fabrication technique for microfluidic systems that is both flexible and cost-effective, allowing new designs and mass-production capabilities.
High Density Through-Wafer Electrical Interconnects for Direct-Chip-Attach, Device-Scale MEMS Packaging
Authors: Neysmith Jordan , Baldwin Daniel F. 
Published: November 2021

Abstract
This paper outlines the motivation behind, and fabrication process for, a novel through-wafer electrical interconnect structure. The interconnect was designed in order to test the feasibility of routing electrical signals through full thickness silicon wafers. The completed interconnect is compatible with solder-based direct-chip-attach (DCA) processing and CMOS circuitry. The core of the through-wafer electrical interconnect structure consists of a high-aspect-ratio via which is subsequently insulated and metallized. On the wafer backside, an under bump metallurgy (UBM) is added around the via opening and a solder bump is formed to complete the interconnect.
Optically-Driven Microstructures Fabricated by Two-Photon Microstereolithography
Authors: Maruo Shoji , Ikuta Koji 
Published: November 2021

Abstract
Freely movable microstructures were made by the use of two-photon microstereolithography with 0.2 micrometers resolution. in our method, movable microstructures are fabricated by fast scanning a focal point through the inside of liquid photopolymerizable resin. Since the method does not need sacrificial layers normally required in major micromachining such as surface micromachining and LIGA process, the fabrication process of movable structures can be drastically simplified. In addition, the movable microstructures were successfully driven by laser-scanning manipulation based on radiation pressure of a focused laser beam. In a preliminary experiment, a micro gear (External diameter: 14 μm) was rotated around an attached shaft at 7.7 rpm by focusing a laser beam on the gear and scanning circularly. Such light-driven micromechanism will provide us diverse microdevices.
Screening Analysis for EPACT-Covered Commercial HVAC and Water-Heating Equipment
Authors: Somasundaram S. , Winiarski D. W. , Belzer D. B. 
Published: November 2021

Abstract
The Energy Policy and Conservation Act (EPCA), as amended by the Energy Policy Act of 1992 (EPACT), establishes that the U.S. Department of Energy (DOE) regulate efficiency levels of certain commercial heating, ventilating, and air-conditioning (HVAC) and service water-heating (SWH) equipment categories. Initial minimum efficiency levels for products falling under these categories were established in EPACT, based on the requirements in ASHRAE/IES Standard 90.1-1989. EPCA requirements state that, if the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE) amends efficiency levels prescribed in Standard 90.1-1989, then DOE must establish an amended uniform national manufacturing standard at the minimum level specified in amended Standard 90.1.
On October 29, 1999, ASHRAE approved the amended Standard 90.1 (Standard 90.1-1999), which increases the minimum efficiency levels for some of the commercial HVAC and SWH equipment covered by EPCA 92. DOE asked Pacific Northwest National Laboratory (PNNL)2 to conduct a screening analysis to determine the energy-savings potential of the efficiency levels listed in Standard 90.1-1999. The analysis estimated the annual national energy savings and carbon emissions reductions that would result if the EPACT-covered products were required to meet these efficiency levels, and additional energy-savings potential for these products if they exceeded these levels.
From 2004 through 2030, the estimated national energy savings achieved by adopting Standard 90.1-1999 efficiency levels for spacecooling equipment is about 3 quadrillion Btu (quads3). The energy savings potential for space-heating equipment is about 0.5 quad and for water-heating equipment is about 0.06 quad. The cumulative commercial-sector building energy consumption during the same time period is estimated to be 485 quads. The total carbon emissions reduction is about 52 millions of metric tons (MMtons).
Decision Support Tools for Managing Unpredictability in the Supply Chain
Authors: Vesier Carol 
Published: November 2021

Abstract
Effectively managing unpredictability requires decision support tools that can predict the financial and business outcomes of various supply chain strategies. This paper will discuss the role of these decision support tools and their characteristics as well as review a case study. In the case study, decision support tools facilitated development of strategies that increased after tax profit by $140 Million. These strategies included:
• Reliability improvement strategy: Identifying the reliability improvements that offered the biggest profitability impact.
• Supply chain strategy: Defining inventory management and production scheduling rules that ensured order shipment within two days.
• Capital investment strategy: Defining when new capacity should come on line as well as the minimum capital investment.
State of the Art Demanufacturing of Electronic Equipment for Reuse and Recycling (DEER2)
Authors: Colon Nelson , Battista Laura , Kuntz Glenn , Allen Woody 
Published: November 2021

Abstract
The disposal of electronic equipment in landfills is receiving significantly increased consideration due to the unknown impact of the environmental hazards they contain. It is also estimated that more than 63.4 million personal computers (PCs) and workstations will be come obsolete in the year 2005 in the United States alone. The DOD projects an annual disposal requirement for more than 25 million pounds of electronic equipment. While computers originating from the Department of Defense (DOD) represent only ten percent (10%) of the total electronic scrap found in landfills, ninety percent (90%) of this scrap consists of military-unique electronic equipment (i.e., test equipment, radios and radar equipment); the remaining 10% is desktop equipment (Federal Electronic Asset Management Task Force Final Report to the Federal Environmental Executive February 16, 1999 Draft Working Copy.) The sheer volume of electronic material, coupled with environmental considerations, is prompting states to keep electronic equipment out of landfills. Consequently, the Department of Defense and other Federal Agencies are voluntarily striving to dispose of its inactive, obsolete or surplus electronic scrap by implementing demanufacturing, reusing, and recycling options rather than landfilling. One way the Department of Defense is addressing the environmental concerns associated with the disposal of its inactive, obsolete or surplus electronic equipment is through the DEER2 Program (Demanufacturing of Electronic Equipment for Reuse and Recycling). This program will develop, demonstrate and validate technology enhancements to facilitate separation and decontamination of materials, tracking, glass and plastics reprocessing and reuse, and precious metals recovery. These innovations will take place in a state of the art technology facility located in Largo, Florida.
Mitigating Environmental and Occupational Health Concerns for the Electronic Demanufacturing Industry
Authors: Gibson LuAnn 
Published: November 2021

Abstract
There are numerous aspects of the electronics demanufacturing industry that may be scrutinized by Occupational Safety and Health regulators. In older computer equipment, there may be materials that have since been banned from use in industry, such as PCBs. Workers disassembling electronic equipment need to be able to recognize components containing this hazardous material. Disassemblers are also exposed to lifting and cutting hazards in their activities. Those who shred or grind their electronics may be exposed to particulated heavy metals or silica, as well as dangerous levels of noise. When electronic components are removed from circuit boards, melting the solder will release lead fumes that must be properly ventilated. Recent and pending changes in OSHA requirements will affect electronics demanufacturers. Forklift standards were revised March 1, 1999, silica exposure limits may soon be reduced, and an ergonomics standard is pending. Universal and waste must be properly handled and stored in ways that comply with regulations and protect the safety and health of the workers. As a new but growing industry, electronics demanufacturers and recylers must remain aware of potential errors that could cost tens of thousands of dollars in OSHA fines or workers’ compensation claims.
Some Equivalences in the Theory of Linear Viscoelasticity and Their Implications in Modeling and Simulation
Authors: Papoulia Katerina D. , Panoskaltsis Vassilis P. , Korovajchuk Igor 
Published: November 2021

Abstract
A class of linear viscoelastic models is examined which accurately represent the response of many materials in a wide frequency range. These include power law and logarithmic type models, such as those of fractional order, the Kuhn model of linear viscoelasticity and generalizations thereof. An equivalence between the fractional element and the generalized Kuhn model is established. A continuous representation of these models is naturally available. It is shown that a discrete rheological representation, in the form of series of springs and dashpots, is also possible. This allows an internal variable formulation, which establishes the thermodynamic admissibility of this class of models, in the sense that they satisfy the dissipation inequality. Introduction of appropriate state variables leads to convolution type equations, which, in the finite deformation case, retain much of the structure of linear viscoelasticity. Numerical implementation of the models is enhanced by the equivalence principles. It is shown that the accuracy expected of a long chain of classical structural units is achieved with a greatly reduced number of model parameters.
Development of a New Technique for Measuring Volume Change of Dry Particulate Systems Under Very Low Confining Pressures
Authors: Abdel-Hadi Ali I. , Cristescu N. D. , Cazacu O. , Bucklin Ray A. 
Published: November 2021

Abstract
A new technique has been developed to measure volume change at very low confining pressures. Such low confining stress levels may be experienced in typical powder technology applications (storage and transport of particulate systems). The aim of this technique is to obtain more accurate information on the deformation, failure and flow behavior of cohesive powders under a variety of loading conditions and deformation rates. The technique allows covering the entire pressure regime that is covered by commercially available and industrially applied powder flow testers. It bridges the gap of multiple devices, whose ranges of test conditions do not overlap, thus facilitating cross-calibration of equipment and increases confidence (and reliability) of all compaction data obtained. The investigation of the effect of initial porosity on powder flowability was chosen to test the new experimental setup.
In particular, triaxial tests have been carried out on samples of different particulate systems and the results have been presented at different confining pressures and on samples of different initial porosities.
Study of Road Damage Potentials of Mixed Traffic
Authors: Romero José A. , Lozano Alejandro 
Published: November 2021

Abstract
Dynamic interactions between the mixed traffic situations and the pavement are investigated through analysis of accumulated stored energy within the pavement. The proposed methodology integrates the dynamic response of heavy vehicles population within the mixed traffic with the primary pavement response and an objective pavement damage measure. The results attained from the proposed methodology revealed reasonably good correlation with the AASHO data on the rut depth. The proposed methodology is applied to establish the influence of traffic distribution, time of the day, weather temperature condition, average traffic speed and the type of traffic distribution on the accumulated stored energy of the pavement. The results show that a uniform traffic distribution can yield considerable reduction in the stored energy and thus the damage potentials of the mixed traffic.
Optimum Design of an A-Pillar Trim With Rib Structures for Occupant Head Protection
Authors: Kim Hyoung-Gon , Kang Shinill 
Published: November 2021

Abstract
NHTSA (National Highway Traffic Safety Administration) has been conducting biomechanical studies to reduce head injuries sustained during automotive collision. Furthermore, NHTSA added the new regulation to the FMVSS201 (Federal Motor Vehicle Safety Standard), limiting the equivalent HIC (Head Injury Criterion) value under 1000. In the present study, a methodology is developed for the optimum design of the A-pillar trim with rib structures, which can maximize the energy dissipation during the head impact. The design variables for the rib structures are the transverse spacing, the longitudinal spacing, and the thickness. The required set of design variables is decided on the bases of the design of experiments. A series of simulations for head impact to A-pillar trim are carried out by using the LS-DYNA3D, and the HIC(d) values are computed using results from simulations, which utilize design variables determined by a combination of the central composite design and the full factorial design. A proper regression function with R-square value above 0.9 was constructed using the response surface method, and it was used as an objective function for optimization. A HIC(d) value under 850 for 15mph head-trim impact was obtained using the rib structures suggested by the present design methodology.
Swing Reduction of Ropeway Carriers by Means of Inclined Pendulum Trajectory and Ball Rolling Type Damping Equipment
Authors: Sato Hisao 
Published: November 2021

Abstract
Ropeway systems provide transportation using carriers that are suspended from ropes. From the view point of transportation safety, an important factor is to improve the windproof performance for carriers. It is especially important to reduce the amount of rolling movement caused to carriers by lateral winds.
In order to improve the windproof performance for carriers of ropeway systems, this report presents an inclined pendulum trajectory and ball rolling type damping equipment as a carrier swing damping equipment, and also describes the test results of the scale model experiments performed for investigating its effect.
Numerical Simulation of Co-Injection Molding
Authors: Wang James T. 
Published: November 2021

Abstract
In the co-injection molding process, two (or more) different polymers are injected into the cavity simultaneously or sequentially. Different properties of these two polymers and their distribution in the cavity greatly affect the applications of this molding process. The skin layer can use special polymers to provide good appearance and texture, strength, chemical resistance, EMI shielding and other functions. The core layer can use recycled or inexpensive materials. Together these can improve part quality and lower the cost.
However, due to the dynamic interaction of two polymers in the manufacturing process and their difference in properties, process control becomes more complicated and process design becomes a challenge. The rules used for the traditional injection molding process design may not always be useful for co-injection molding any more. An integrated CAE software has been developed to simulate the co-injection molding process. In this study, the capability and usefulness of the CAE tool will be shown. The control of polymer distribution will be discussed. The effects of polymer properties and their distribution on part quality will also be studied.
CAE for Injection Molding: What’s Next?
Authors: Wang Kuo K. 
Published: November 2021

Abstract
After a well-focused research effort over the past quarter of a century, CAE for injection molding has become a common engineering tool used widely in industrial practice. Today, part and mold designers readily make use of CAE software tools to make rational design decisions based on scientific principles rather than solely on prior experiences. While the common goal of the industry is to produce plastic parts anywhere in the world at the lowest cost, with the best quality and fastest speed to market, a missing link in an integrated production system seems to lie in the ability at the shop floor to control the molding process automatically and adaptively without compromising part quality. As the IT (Information Technologies) and Web-based engineering continue to strive, the injection molding industry would benefit immensely to achieve its goals. This paper discusses some issues on technical challenges and opportunities.
Modeling of Hydrostatic Pressure Effect on Progressive Damage in Particulate Composites
Authors: Kwon Y. W. , Liu C. T. 
Published: November 2021

Abstract
Hydrostatic pressure affects the damage growth in a particulate composite. As a result, an analytical model was presented to represent the damage growth in a particulate composite under various hydrostatic pressures. The model was based on a multi-level approach with damage description at the micro-level. A damage theory was presented to describe the material behavior under hydrostatic pressure. The predicted stress-strain curves compared well with the experimental measurements. Furthermore, the initial crack size at a notch tip was studied with and without hydrostatic pressure.
Finite Element Modeling for Vibration Analysis of Constrained Layer Damping Treated Structures
Authors: Xu Yanchu , Chen Dennis 
Published: November 2021

Abstract
A compound plate element is presented for modeling all layers of the damped structure into a single element. By associating deformations of the damping layer to those of base structure layer and constraining layer, the kinetic and potential energies of the damping layer as well as those of base and constraining layers can be derived. Then the element mass and stiffness matrices can be obtained for all layers as a whole. The newly derived element formulation results in significant simplification of constrained layer modeling and dramatic reduction of element density while maintaining the desired accuracy. The use of the element also allows direct and more accurate calculation of structural modal damping in modal analysis.
Ballistic Impact Analysis of the Human Thorax With a Protective Body Armor
Authors: Kwon Y. W. , Jolly J. E. , Hughes T. A. 
Published: November 2021

Abstract
The biomechanical response of a finite element model of the human thorax and a protective body armor system was studied under impact loading from a projectile. The objective of the study was to create a viable finite element model of the human thorax. The model was validated by comparing the results of tests of body armor systems conducted on cadavers to results obtained from finite element analysis. A parametric study was undertaken to determine the essential components of the model. The results from this investigation determined that the path of force propagation from a body armor system to the thorax upon bullet impact is directly through the vest to the sternum and then through the skeleton to the rest of the body. Thus, any parameters that affect the components in this pathway were essential to the model. This included the muscles, their geometries, material properties, and viscosity, as well as the Young’s modulus of the sternochondral cartilage and the bones themselves.
Influence of Brazing on the Heat Transfer Performance of Fins in Radiators
Authors: Sundén Bengt , Abdon Andreas , Eriksson Daniel 
Published: November 2021

Abstract
The performance of a radiator copper fin is considered as the braze joint between the fin and the brass tube is not perfect. The influence of different thermophysical properties of the brazing materials, created intermetallic compounds and possible air gaps is considered. Numerical methods for both two-dimensional and one-dimensional calculations have been developed. The finite volume technique is applied and in the two-dimensional case, boundary fitted coordinates are used. Heat conduction in the fin and braze joint coupled with convective heat transfer in a gas stream is analysed. Results in terms of fin temperature distributions and fin efficiencies are provided. It is found that the detrimental effect of a poor braze joint is not as large as reported previously in the literature.