bluuebunny/crossref_metadata_2025_split huggingface dataset:
Instability Modes of Two-Phase Flows in a Mixing-Layer Microdevice
Authors: Yu Tak For , Lee Sylvanus Yuk Kwan , Zohar Yitshak , Wong Man 
Published: November 2021

Abstract
Extensive development of biomedical and chemical analytic microdevices involves microscale fluid flows. Merging of fluid streams is expected to be a key feature in such devices. An integrated microsystem consisting of merging microchannels and distributed pressure microsensors has been designed and characterized to study this phenomenon on a microscale. The two narrow, uniform and identical channels merged smoothly into a wide, straight and uniform channel downstream of a splitter plate. All of the devices were fabricated using standard micromachining techniques. Mass flow rates and pressure distributions were measured for single-phase gas flow in order to characterize the device. The experimental results indicated that the flow developed when both inlets were connected together to the gas source could be modeled as gas flow through a straight and uniform microchannel. The flow through a single branch while the other was blocked, however, could be modeled as gas flow through a pair of microchannels in series. Flow visualizations of two-phase flows have been conducted when driving liquid and gas through the inlet channels. Several instability modes of the gas/liquid interface have been observed as a function of the pressure difference between the two streams at the merging location.
Micropump Design for Optimum Pressure/Flow Characteristics
Authors: Williams Brian E. , Forster Fred K. 
Published: November 2021

Abstract
Until now there have been no reports of design techniques that include a means for developing pumps that can pump against higher pressure loads at the cost of less volume flow rate delivered to the load or vice versa. We address this problem for membrane micropumps that incorporate no-moving-parts valves (NMPV). A design approach is presented that utilizes a linear low-order model, finite element analysis to optimize piezoelectric actuation, and an algorithm to interrogate a design space of membrane thickness and valve size for any specified pressure load. The results indicate that optimum designs are relatively far from existing pumps and that significant improvements are possible. These gains appear to be due to the ability of the design approach to select non-obvious combinations of membrane stiffness and valve size to better “tune” the system, which is crucial in the case of NMPV pump, because excellent resonant behavior can make up for the fact that the valves do not open and close. Another important observation was that the optimal design point for pressure was not the same as for flow. This result is an indication that pumps can be designed for pressure or flow through careful design.
Precision Alignment Packaging for Microsystems With Multiple Fluid Connections
Authors: Galambos Paul , Benavides Gilbert L. , Okandan Murat , Jenkins Mark W. , Hetherington Dale 
Published: November 2021

Abstract
The application of microfluidic Microsystems to solve real world problems depends on effective packaging techniques. In this paper, we report on packaging methods that allow the connection of multiple fluid lines to a microfluidic chip. Eight different fluid connections are made in a 5 mm square area (100 connections possible) using a flip chip aligner/bonder with precise alignment on the order of 10 microns between holes (1 micron precision possible). The critical fluid connections are made using 0.002 inch thick double sided adhesive tape and are shown to hold greater than 20 atm of pressure without leaking. The packaging flow manifold and assembly methods are suitable for inexpensive mass production and are compatible with existing electronics packaging technologies.
Design, Fabrication, and Testing of a Continuous Flow, Submicroliter Scale PCR for the Analysis of Plant Genomes
Authors: Zheng Wei , Chen Shaochen 
Published: November 2021

Abstract
In recent years, many micromachined polymerase chain reaction (PCR) chips have been reported. These miniaturized PCR chips have great advantages such as the significant reduction in reagent costs and vastly reduced reaction times over the conventional PCR reactions. In this paper a micro analysis system that will allow submicro-liter scale, continuous-flow PCR to be conducted in a glass chip has been presented. This glass chip is fabricated through thermally bonding two pyrex 7740 glass wafers. One pyrex wafer is etched to form the 20-cycle microchannel with 80 microns wide and 30 microns deep. Another pyrex wafer is thermally bonded to the etched wafer to produce closed a continuous microchannel for PCR. The total length of the microchannel is 0.5 m. This PCR chip has a significant reagent reduction with a volume of less than 1 micro-liter. With 1 micro-liter reagent we obtain a total reaction time of 0.5 min to 3 min depending on various flow rates. This analytical chip is fabricated using standard micromachining techniques with a total size of 56 mm × 24 mm × 1 mm. The advantages of this chip include very small quantities of reagent needed, rapid thermal cycling, standard micromachining processes and batch fabrication which result in a significant cost reduction.
Design and Analysis of a Miniature Rotary Wankel Compressor
Authors: Finger G. W. , Kapat J. S. , Chow L. C. 
Published: November 2021

Abstract
Design and analysis of a meso-scale rotary Wankel compressor is presented here. The compressor is primarily designed for a hand-held power generation system, based on a modified Brayton cycle and capable of producing 20 W with a specific energy of 2400 to 3800 W-hr/kg for usage duration of 72 to 240 hours. The small size of the overall system makes the conventional design rules and concepts inappropriate, thus requiring new design concepts for the compressor and other components.
In the current design, the major axis of the epitrochoid is 14 mm. The three-lobed rotor is driven by a drive shaft through an internal gear system such that each revolution of the rotor corresponds to 3 revolutions of the drive shaft and 6 compression “strokes”. There are two intake ports and two discharge ports. The valves within these ports operate to limit the pressure ratio to 2.5, the target of the design. Rotor thickness is 9.1 mm and at a rotational speed of 5000 rpm, the compressor can provide a flow rate of 0.138 g/s air, as needed by the power generation system.
The pressure ratio of the compressor is a function of geometry (not rotor speed), and hence this design is well-suited for load following in a variable load application. Its drive shaft can be de-coupled from other system components of the power generation system. This mechanical isolation can lead to thermal isolation, which is essential for miniature power generation devices.
Micro-stereo lithography and micro-EDM appear to be the best methods to fabricate the necessary components of the compressor. Micro-stereo lithography, in particular, can provide a seamlessly integrated compressor, thus reducing the integration and assembly cost. Micro-EDM is more suited for production of large batch sizes because of the relatively high initial cost. More sophisticated micro-fabrication methods such as LIGA, UV-LIGA and lithography SU-8 can also be used. However, since the device thickness is rather large compared to what is typically done with these methods, multiple layers need to be bonded in both of these approaches because of the large thickness of the proposed design.
Resound: A Full Spectrum Modelling Method
Authors: Shorter P. J. , Gardner B. K. , Patil A. 
Published: November 2021

Abstract
The response of a structural-acoustic system in the mid-frequency range typically consists of both long and short wavelength behavior. Modeling the short-wavelength behavior deterministically is usually computationally prohibitive and structural-acoustic techniques such as SEA are often adopted. However, SEA cannot adequately capture the long-wavelength global behavior of the system. Recent work aimed at addressing the mid-frequency problem has led to the development of a hybrid approach based on a wavenumber partitioning scheme [1]. This paper provides an overview of the approach and presents some recent research developments.
Design and Optimization of Broadband Vibration Absorbers for Noise Control
Authors: Heinze Emily S. , Grissom Michael D. , Belegundu Ashok 
Published: November 2021

Abstract
A general and practical approach is presented for optimizing structural additions to a base structure for broadband dynamic objectives when the base structure is excited by an arbitrary forcing function. The mode shapes and natural frequencies of the base structure are first found using a commercial finite element code or an experimental modal analysis. The mode shapes are used as basis shapes to reduce the size of the equations. The structural additions are then added as impedances into the reduced modal model. An efficient analysis algorithm is presented to reduce the computational burden for broadband analysis and optimization loops. The power transferred into a Broadband Vibration Absorber (BBVA) from a base structure is maximized as an example application. The numerical results are experimentally verified demonstrating the practical design capabilities of the method.
High-Order Optimized Numerical Schemes for Computational Aeroacoustics
Authors: Zheng S. , Zhuang M. 
Published: November 2021

Abstract
This paper presents a new optimization approach for the high-order finite difference schemes. Due to the fact that it is common for a sound field to consist of several dominant wavenumbers, the proposed numerical schemes are optimized at these dominant wavenumbers instead of over a range of wavenumber. These optimized multi-component schemes, as referred to in this paper, give very accurate solutions if used to predict an acoustic wave traveling with these dominant wavenumbers. In addition, for broadband waves, it is shown that the performance of the optimized upwind multi-component scheme is comparable to that of the optimized upwind broadband scheme, which is optimized over a range of wavenumber. The results of the Fourier analysis also show that the optimized central multi-component schemes are at least comparable to if not better than the optimized central broadband schemes when solving broadband waves.
Siting and Safety Associated With a Municipal Skate Park
Authors: Pyatt D. W. 
Published: November 2021

Abstract
The town of Mount Airy, MD chose to construct a skateboard and roller blade park in 1998 because of the many young adults skating on parking lots, streets, and sidewalks within the Town Limits. Many citizens and merchants complained of hazards both to the young adults as well as to pedestrians and drivers. Several sites were selected for evaluation; the final site selection was an existing Town Park. The next step was to design the Skate Park to satisfy both the recreational needs and safety of skaters of all ages and skill levels. In this capacity, the author worked with skating groups, including professional skaters, and insurance experts who insured the Town’s facilities. A design was made, submitted for bids, and constructed in October 1999. The Skate Park has operated safely in the past year and has won recognition as a skater’s park. This paper will discuss how this was accomplished.
The Role of the Engineer in 21st Century Industry
Authors: Koenig Daniel T. 
Published: November 2021

Abstract
1. What you think of as the traditional role of the engineer in Industry no longer exists.
2. Engineers no longer occupy purely technical positions.
3. There are more engineers in traditionally nontechnical positions than in structured Design, Mfg. Engineering, and R&D positions.
4. These facts are not discipline specific, but true across the board for all types of Engineering.
5. This means that how we prepare engineers for their first jobs and how we continue to learn, or as Dick Golstein says, how we engage in life long learning is undergoing radical change.
6. The fact is engineers in industry are pragmatic technically trained business persons, not technologists or scientist and we need to recognize that basic truth.
7. Now, with this as the state of the engineers position in industry, I’d like to discuss the changing nature of the strategy of operations that the engineer has to contend with and the education needs to support that strategy.
Bioengineering: From Mechanics and Devices to Tissue Engineering and Genetics
Authors: Phillips Winfred M. 
Published: November 2021

Abstract
The National Institutes of Health (NIH) defines bioengineering as an interdisciplinary field that applies physical, chemical, and mathematical sciences and engineering principles to the study of biology, medicine, behavior, and health. Bioengineering advances knowledge from the molecular to the organ systems level, and develops new and novel biologics, materials, processes, implants, devices, and informational approaches for the prevention, diagnosis, and treatment of disease, for patient rehabilitation, and for improving health.
Enormous contributions to the advancement of health care have been made through bioengineering. It has been instrumental in establishing the United States as the world leader in health care technology, as evidenced by a $4.6 billion trade surplus for this sector in 1993. The field, through basic and applied research and technology assessment, has given us such devices as the pacemaker, orthopedic implants, and noninvasive diagnostic imaging. Bioengineers have developed new processes for manufacturing products in the pharmaceutical and biotechnology industries. An example is the manufacturing of human insulin, the first product based on recombinant DNA technology, where bioengineering was critical to the ability to commercialize the product.
These continuing contributions and unprecedented growth, focus, and opportunity in bioengineering will be a continuing frontier and opportunity for the United States and the world.
Microsensors, MEMS and NEMS Based Complex Adaptive Smart Devices and Systems
Authors: Varadan Vijay K. 
Published: November 2021

Abstract
The microelectronics industry has seen explosive growth during the last thirty years. Extremely large markets for logic and memory devices have driven the development of new materials, and technologies for the fabrication of even more complex devices with features sizes now down at the sub micron level. Recent interest has arisen in employing these materials, tools and technologies for the fabrication of miniature sensors and actuators and their integration with electronic circuits to produce smart devices and MicroElectroMechanical Systems (MEMS). This effort offers the promise of:
1. Increasing the performance and manufacturability of both sensors and actuators by exploiting new batch fabrication processes developed for the IC and microelectronics industry. Examples include micro stereo lithographic and micro molding techniques.
2. Developing novel classes of materials and mechanical structures not possible previously, such as diamond like carbon, silicon carbide and carbon nanotubes, micro-turbines and micro-engines.
3. Development of technologies for the system level and wafer level integration of micro components at the nanometer precision, such as self-assembly techniques and robotic manipulation.
4. Development of control and communication systems for MEMS devices, such as optical and RF wireless, and power delivery systems.
Latest Permian–Triassic magmatism of the Taimyr Peninsula: New evidence for a connection to the Siberian Traps large igneous province
Authors: Kurapov Mikhail , Ershova Victoria , Khudoley Andrei , Luchitskaya Marina , Stockli Daniel , Makariev Alexander , Makarieva Elena , Vishnevskaya Irina 
Published: November 2021

Abstract
This study presents new whole rock major and trace element, Sr-Nd isotopic, petrographic, and geochronologic data for seven latest Permian (Changhsingian)–Late Triassic (Carnian) granitoid intrusions of the northwestern and northeastern Taimyr Peninsula in the Russian High Arctic. U-Pb zircon ages, obtained using secondary ion mass spectrometry (SIMS), sensitive high-resolution ion microprobe (SHRIMP), and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), define the crystallization age of the Taimyr intrusions studied as ranging from ca. 253 Ma to 228 Ma, which suggests two magmatic pulses of latest Permian–Early Triassic and Middle–Late Triassic age. Ar-Ar dating of biotite and amphibole indicate rapid cooling of the intrusions studied, but Ar-Ar ages of several samples were reset by secondary heating and hydrothermal activity induced by the Middle–Late Triassic magmatic pulse. Petrographic data distinguish two groups of granites: syenite–monzonites and granites–granodiorites. Sr-Nd isotopic data, obtained from the same intrusions, show a variation of initial (87Sr/86Sr)i ratios between 0.70377 and 0.70607, and εNd(t) values range between –6.9 and 1.2. We propose that the geochemical and isotopic compositions of the Late Permian–Triassic Taimyr granites record the existence of a magma mush zone that was generated by the two pulses of Siberian Traps large igneous province (LIP) magmatism.
Secular trends in early motor development between 1980 and 2010 in Japan
Authors: Yoshii Keisuke , Michihata Nobuaki , Hirasawa Kyoko , Nagata Satoru , Morisaki Naho 
Published: November 2021

ObjectiveRecent changes in birth characteristics in Japan may have a potential influence on children’s developments. Therefore, we investigated secular trends in gross motor milestones.DesignData were collected from an official Japanese nationwide serial cross-sectional survey conducted every 10 years since 1960. 22 320 participants aged 2–18 months were identified from the four surveys from 1980 to 2010.OutcomesWe assessed whether or not a child achieved four gross motor milestones including rolling over (rolling), sitting without support (sitting), standing with support (standing) and walking alone (walking). The target age was defined as the age when the attainment rate ranged from >5% to >95% of the total. Multivariate logistic regression models were fitted.ResultsThe final cohort included 20 570 children. The target ages were determined as follows: 3–6 months for rolling; 5–9 months for sitting; 6–11 months for standing; and 9–15 months for walking. The attainment rates of sitting, standing and walking in 1990 were higher than those in 2010, even after adjusting for child characteristics (sitting: adjusted OR (aOR)=2.07 (95% CI 1.62 to 2.65); standing: aOR=1.63 (95% CI 1.32 to 2.02); and walking: aOR=1.61 (95% CI 1.34 to 1.95)).ConclusionsThe proportion of children who attained three motor milestones (sitting, standing and walking) by set target ages decreased between 1990 and 2010. The contribution of birth characteristics including a decrease in gestational age and fetal growth, as well as changes in other child characteristics, failed to explain why this decrease occurred.
Evaluation of a contactless neonatal physiological monitor in Nairobi, Kenya
Authors: Wang Dee , Macharia William M , Ochieng Roseline , Chomba Dorothy , Hadida Yifat S , Karasik Roman , Dunsmuir Dustin , Coleman Jesse , Zhou Guohai , Ginsburg Amy Sarah , Ansermino J Mark 
Published: November 2021

BackgroundGlobally, 2.5 million neonates died in 2018, accounting for 46% of under-5 deaths. Multiparameter continuous physiological monitoring (MCPM) of neonates allows for early detection and treatment of life-threatening health problems. However, neonatal monitoring technology is largely unavailable in low-resource settings.MethodsIn four evaluation rounds, we prospectively compared the accuracy of the EarlySense under-mattress device to the Masimo Rad-97 pulse CO-oximeter with capnography reference device for heart rate (HR) and respiratory rate (RR) measurements in neonates in Kenya. EarlySense algorithm optimisations were made between evaluation rounds. In each evaluation round, we compared 200 randomly selected epochs of data using Bland-Altman plots and generated Clarke error grids with zones of 20% to aid in clinical interpretation.ResultsBetween 9 July 2019 and 8 January 2020, we collected 280 hours of MCPM data from 76 enrolled neonates. At the final evaluation round, the EarlySense MCPM device demonstrated a bias of −0.8 beats/minute for HR and 1.6 breaths/minute for RR, and normalised spread between the 95% upper and lower limits of agreement of 6.2% for HR and 27.3% for RR. Agreement between the two MCPM devices met the a priori–defined threshold of 30%. The Clarke error grids showed that all observations for HR and 197/200 for RR were within a 20% difference.ConclusionOur research indicates that there is acceptable agreement between the EarlySense and Masimo MCPM devices in the context of large within-subject variability; however, further studies establishing cost-effectiveness and clinical effectiveness are needed before large-scale implementation of the EarlySense MCPM device in neonates.Trial registration numberNCT03920761.
Ethnic minority status as social determinant for COVID-19 infection, hospitalisation, severity, ICU admission and deaths in the early phase of the pandemic: a meta-analysis
Authors: Agyemang Charles , Richters Anke , Jolani Shahab , Hendriks Stevie , Zalpuri Saurabh , Yu Evan , Pijls Bart , Prins Maria , Stronks Karien , Zeegers Maurice P 
Published: November 2021

IntroductionEarly literature on the COVID-19 pandemic indicated striking ethnic inequalities in SARS-CoV-2-related outcomes. This systematic review and meta-analysis aimed to describe the presence and magnitude of associations between ethnic groups and COVID-19-related outcomes.MethodsPubMed and Embase were searched from December 2019 through September 2020. Studies reporting extractable data (ie, crude numbers, and unadjusted or adjusted risk/ORs) by ethnic group on any of the five studied outcomes: confirmed COVID-19 infection in the general population, hospitalisation among infected patients, and disease severity, intensive care unit (ICU) admission and mortality among hospitalised patients with SARS-CoV-2 infection, were included using standardised electronic data extraction forms. We pooled data from published studies using random-effects meta-analysis.Results58 studies were included from seven countries in four continents, mostly retrospective cohort studies, covering a total of almost 10 million individuals from the first wave until the summer of 2020. The risk of diagnosed SARS-CoV-2 infection was higher in most ethnic minority groups than their White counterparts in North American and Europe with the differences remaining in the US ethnic minorities after adjustment for confounders and explanatory factors. Among people with confirmed infection, African-Americans and Hispanic-Americans were also more likely than White-Americans to be hospitalised with SARS-CoV-2 infection. No increased risk of COVID-19 outcomes (ie, severe disease, ICU admission and death) was found among ethnic minority patients once hospitalised, except for a higher risk of death among ethnic minorities in Brazil.ConclusionThe risk of SARS-CoV-2 diagnosis was higher in most ethnic minorities, but once hospitalised, no clear inequalities exist in COVID-19 outcomes except for the high risk of death in ethnic minorities in Brazil. The findings highlight the necessity to tackle disparities in social determinants of health, preventative opportunities and delay in healthcare use. Ethnic minorities should specifically be considered in policies mitigating negative impacts of the pandemic.PROSPERO registration numberCRD42020180085.