bluuebunny/crossref_metadata_2025_split huggingface dataset:
It is about who you know (and how you help them): Insights from staff and donors about how to recruit and retain a panel of committed anti‐D donors
Authors: Thorpe Rachel , Kruse Sarah P. , Masser Barbara M. 
Published: January 2022

AbstractBackground and ObjectivesMaintaining a panel of committed anti‐D donors is crucial for the production of anti‐D immunoglobulin to prevent haemolytic disease of the foetus and newborn. Given low numbers of donors in the Australian panel, there is a need to better understand motivators and barriers specific to anti‐D donors.Materials and MethodsA qualitative approach was used to gather perspectives of staff and current anti‐D donors in Australia. Focus groups were held with staff involved with the anti‐D programme. An asynchronous online discussion forum and interviews were conducted with donors. All data were coded using deductive and inductive thematic analysis.ResultsStaff stressed the importance of recruiting donors who met their own informal criteria as well as the formal selection criteria in order to maximize the chances of donors committing to making regular plasma donations. In contrast, donors were motivated by having a personal connection to anti‐D, the recipient group and being eligible to join the programme. Support from staff and understanding the value of their donations also helped donors overcome concerns about the risks of joining the programme and reduced barriers to remaining in the programme.ConclusionAnti‐D donors in Australia are motivated by multiple factors, including knowing who the recipient is, and dedicated staff are integral to building donors' commitment through education and support. Findings suggest the current approach to recruitment could be broadened to include all donors who meet formal selection criteria, with retention enhanced by reinforcing and rewarding the motives identified by donors for donating.
Mathematical Method to Assess the Yin-Yang Balance of Commercial Complexes’ Entrances
Authors: Zhang Yucheng , So Albert , Ge Xin Janet 
Published: January 2022

Shopping malls are important landmarks of modern and sustainable cities as they are substantial business and investment by themselves, and as they also facilitate the social activities of communities. Entrances to shopping malls provide a first impression to customers, thus affecting the business performance of the malls. This paper presents a method to assess the entrances of modern shopping malls by applying traditionally qualitative Feng shui practices quantitatively with an innovative mathematical model. The assessment is based on the manipulation of the yin-and-yang concept applied to the layout of Ming tang (bright court) as the focus of consideration. By applying this novel approach to three shopping malls in Guangzhou, China as a pilot study to match their commercial performance, our hypothesis appears workable. The ideology of balancing yin and yang may be practically meaningful to urban planning and the successful measurement of such balance could shed light on future studies.
Modeling and Simulation of an Assistive Exoskeleton Leg System With Knee Osteoarthritis and Quadriceps Weakness
Authors: Iscan Mehmet , Yilmaz Cuneyt , Vural Berkem , Eken Huseyin 
Published: January 2022

Abstract
The most common human locomotion problems such as quadriceps weakness, knee osteoarthritis can be healed up by using exoskeleton mechanisms with proper control systems. However, these kinds of abnormalities cannot be easily modeled in terms of engineering perspectives due to a lack of adequate data or unknown dynamics. Also, nature always seeks minimum energy as well as biology, which means that the unknown dynamics can be built by using this phenomenon. In this study, a new system dynamic model had been involved in designing a simple single-legged exoskeleton robot mechanism and its control system to assist partially disabled individuals to improve their quality of locomotion. To determine the specific features of the human gait disorders to interpret their nature in the computer-aided simulation environment, knee osteoarthritis, and quadriceps weakness, which are the common types of such problems, have been chosen as the main interests for this study. By using the lower limb model with anthropometric data, the simulations of disorders have been realized on matlabsimscape environment, which enables us to model the entire exoskeleton system with the three-dimensional parts of the human body. A model of a leg with the disorder was able to be obtained with the utilization of feedback linearization, which is one of the examples of minimum principles in the control theory. A proper gait cycle is achieved with the exoskeleton application and separately for the leg, with approximately 10 deg deviation from the natural property in knee flexion. Finally, it can be seen that the system conversion into such problematic cases with or without an exoskeleton system is accomplished.
Numerical Study of Unsteady Cavitating Flow in an Inducer With Omega Vortex Identification
Authors: Yan Longlong , Gao Bo , Ni Dan , Zhang Ning , Zhou Wenjie 
Published: January 2022

Abstract
To accurately capture the behaviors of cavitation and reveal the unsteady cavitating flow mechanism, a condensate pump inducer is numerically analyzed in a separate numerical experiment with large eddy simulation (LES) at critical cavitation number σind,c under the design point. Based on the new Omega vortex identification method, the correlation between the flow structures and cavities is clearly illustrated. Besides, the pressure fluctuations around the inducer are analyzed. Special emphasis is put on the analysis of the interactions between the cavities, turbulent fluctuations, and vortical flow structures. The Omega vortex identification method could give an overall picture of the whole cavitating flow structures to present a clear correlation between the vortices and cavities. The results show that the shear cavitation dominates the cavitation characteristics under the design point. The pure rigid rotation region mainly concentrates at the edge of the cavities while the other sheet-like cavities near the casing walls are characterized by strong turbulence fluctuations. Besides, based on the analysis of the correlation between the cavities and flow structures, the rotating cavitation under the design point may mainly be attributed to the interaction between the tip leakage vortex cavitation and the next blade.
Flow Characteristics of Gerotor Motors With Pin and Nonpin Designs
Authors: Hsieh Chiu-Fan , Johar Tehseen , Lin Yi-Hao 
Published: January 2022

Abstract
The geometric design of a gerotor motor has a significant impact on its function, performance, quality, reliability and cost. When designing a gerotor motor all these features must be considered. A gerotor motor can be classified into two types based on the geometric design; gerolor (pin design) and gerotor (nonpin design). In this article, geometric parameters of the two design types are discussed briefly and the operation of the gerotor motor is described as well. A numerical analysis is carried out by using computational fluid dynamics (CFD) tool (PumpLinx) to analyze the fluid flow and predict the performance of both types of gerotor designs. Various characteristics of the two designs of the gerotor motor are investigated and compared which include the gerotor design, fluid flowrate, velocity, pressure and output torque. Comparison of the results found out that using pin design gerotor motor, the flowrate, flow velocity, pressure and torque will vary greatly. Nonpin design can significantly reduce variations in all the flow characteristics thereby enhancing the stability and reduction in the leakage risk.
Friction Factor Comparison Between Mixing Length Theory and Empirical Correlation
Authors: Prasad Mahendra 
Published: January 2022

Abstract
Equivalent sand grain roughness is required for estimating friction factor for engineering applications from empirical relation via Haalands equation. The real surfaces are different from the sand grain profile. The correlations for friction factor were derived from the use of discrete roughness elements with regular shapes such as cones and bars. The purpose of the paper is to derive the analytical expression of friction factor for a two-dimensional (2D) semicylindrical roughness (not exactly a three-dimensional (3D) sand grain but for the circular profile of cross-section) using Navier–Stokes equation and mixing length theory. This is compared with the modified series mathematical representation of Haalands equation for friction factor in terms of equivalent sand grain roughness. The comparison is valid for a high Reynolds number where the velocity profile is almost flat beyond the boundary layer and approximately linear all throughout the boundary layer. The high Reynolds number approximation for Haalands equation is derived and the series form of the friction factor compares approximately with the series form derived from first principles, where in the exponents of the series expansion are close.
Estimation of Turbulent Length Scales at a Turbocharger Inlet Using Stereoscopic Particle Image Velocimetry
Authors: Banerjee Deb , Selamet Ahmet , Dehner Rick 
Published: January 2022

Abstract
Stereoscopic particle image velocimetry (SPIV) measurements are carried out at the inlet of a turbocharger compressor at four different shaft speeds from 80,000 rpm to 140,000 rpm and over the entire range of flow rates from choke to mild surge. This paper describes the procedure used in processing the SPIV data leading to the estimates of turbulent length scales—integral, Taylor, and Kolmogorov, to enhance the fundamental understanding and characterization of the compressor inlet flow field. The analysis reveals that at most operating conditions, the three different length scales have markedly different magnitudes, as expected, while they have somewhat similar qualitative distributions with respect to the duct radius. For example, at 80,000 rpm and at a flowrate of 15.7 g/s (mild surge), the longitudinal integral length scale is of the order of 15 mm, the Taylor scale is around 0.5 mm, and the Kolmogorov scale is about 10 μm. With the onset of flow reversal, the turbulent kinetic energy and turbulent intensity at the compressor inlet are observed to increase rapidly, while the magnitudes of the Kolmogorov scale and to a certain extent, the Taylor scale are found to decrease suggesting that the increased turbulence gives rise to even smaller flow structures. The variation of length scales with compressor shaft speed has also been studied.
A Circular Eccentric Vibration Absorber With Circumferentially Graded Acoustic Black Hole Features
Authors: Ji Hongli , Zhao Xiaoning , Wang Ning , Huang Wei , Qiu Jinhao , Cheng Li 
Published: January 2022

Abstract
A previously proposed planar axisymmetric dynamic vibration absorber (DVA), with embedded acoustic black hole (ABH) features, has been shown to suffer from the very selective coupling with the host structure, thus compromising its vibration reduction performance. To tackle the problem, an eccentric ABH-based circular DVA whose thickness profile is tailored according to a circumferential gradient variation is proposed. This new configuration preserves the ABH profile in the radial direction and breaks the axisymmetric of the original DVA design at the same time. While the former permits the ABH features to fully play out in a continuous manner, the later entails a more effective coupling with the host structure. These salient properties have been demonstrated and confirmed both numerically and experimentally by examining a benchmark plate structure. For analyses, a coupling model embracing the host structure and the add-on DVAs is established which allows the calculation of the coupling coefficient, a vital quantity to guide the DVA design. Studies demonstrate the advantages of the proposed DVA over existing designs for the same given mass. The enriched structural coupling and the enhanced modal damping, arising from the eccentric and circumferentially graded ABH design, are shown to be the origin of such improvement. All in all, the physical process underpinning the dynamic absorber principle and waveguide absorber from the host structures is simultaneously consolidated, thus leading to superior broadband structural vibration suppression.
Hybrid Mass Damper: Theoretical and Experimental Power Flow Analysis
Authors: Billon K. , Zhao G. , Collette C. , Chesné S. 
Published: January 2022

Abstract
In this paper, a hybrid mass damper (HMD) and its hyperstability due to a power flow approach are studied. The HMD proposed combines an active control system with an optimal passive device. The initial passive system is an electromagnetic tuned mass damper (TMD) and the control law is a modified velocity feedback with a phase compensator. The resulting hybrid controller system is theoretically hyperstable and ensures fail-safe behavior. Experiments are performed to validate the numerical simulation and provide good results in terms of vibration attenuations. Both excitation from the bottom in the frequency domain and shock response in the time domain are tested and analyzed. The different power flows in terms of active and reactive powers are estimated numerically and experimentally on the inertial damper (passive and active) and on the HMD. Moreover, through a mechanical analogy of the proposed system, it is shown that this hybrid device can be seen as an active realization of an inerter based tuned-mass-damper associated with a sky-hook damper. Observations and analysis provide insight into the hyperstable behavior imposed by the specific control law.
Experimental and Numerical Study of Heat Transfer and Pressure Loss in a Swirl Multi-Pass Channel With Convergent Jet Slots
Authors: Luan Yong , Rao Yu , Wang Kai , Wu Weilong 
Published: January 2022

Abstract
This paper presents a comparative experimental and numerical study of the heat transfer and pressure loss in a swirl multi-pass channel with tangential jet slots, and another baseline multi-pass channel with 180-deg U-bends as a comparison baseline has also been investigated. The tangential jets can induce large-scale swirling flows and significantly enhance the connective heat transfer. The swirl multi-pass channel can be considered as an effective internal cooling strategy for the gas turbine blades. Transient liquid crystal thermography is used to obtain the detailed heat transfer distribution on the internal surfaces of the multi-pass serpentine channels. The heat transfer patterns in the swirl multi-pass channel are quite different from those of the baseline multi-pass channel. Circumferentially, the three heat transfer surfaces, i.e., the bottom, top and side surfaces of the two multi-pass serpentine channels, have roughly similar trend along the flow direction and reach the peak values after the U-bends and jet injections, respectively. Compared with the baseline multi-pass channel, the experimental globally averaged Nusselt number ratios of the last two passes in the swirl multi-pass channel can be increased by up to 82.9%, 104.8%, and 124.6% for the Reynolds numbers 20,000, 40,000, and 60,000, respectively. The differences of globally averaged Nusselt number ratios between the two kinds of multi-pass serpentine channels gradually increase with the Reynolds numbers, which means that the swirl multi-pass channel has higher heat transfer enhancement capability at a higher Reynolds number. The circumferentially uniform heat transfer characteristic of swirling flow also performs well in this study. The high and circumferentially uniform heat transfer is mainly due to the large-scale swirling flow induced by the tangential slots. In more detail, the large-scale swirling flow impinges onto the surface and further induces high tangential velocity near the wall, which destroys the boundary layer flow and thus improves the heat transfer rates at the wall. However, the notable pressure loss of the swirl multi-pass channel should be further controlled reasonably, which is about 5.4 times that of the baseline multi-pass channel. As supplements to the experiments, three-dimensional numerical computations provide more insights into the turbulent flow structure in the two kinds of multi-pass serpentine channels.
Calibration of a Computational Fluid Dynamics Methodology for the Simulation of Roughness Effects on Friction and Heat Transfer in Additive Manufactured Components
Authors: Mazzei Lorenzo , Da Soghe Riccardo , Bianchini Cosimo 
Published: January 2022

AbstractIt is well known from the literature that surface roughness significantly affects friction and heat transfer. This is even more evident for additive manufactured (AM) components, which are taking an increasingly important role in the gas turbine field. However, the exploitation of numerical approaches to improve their design is hindered by the lack of dedicated correlations and computational fluid dynamics (CFD) models developed for such high roughness conditions. Usually, the AM components are simulated considering the surfaces as smooth or applying an equivalent sand-grain roughness (ks) that results in a velocity shift in the boundary layer. However, determining a priori the most appropriate value of ks is challenging, as dozens of correlations are available, returning scattered and uncertain results. A previous work proved how the CFD prediction of friction and heat transfer returns significant deviations, even exploiting the ks values obtained from experimental tests on the very same test case. That work also allowed identification of a promising CFD methodology based on friction and thermal corrections proposed by Aupoix from ONERA. The aim of this work is to further the assessment and calibration activity of the model, by analyzing additional experimental data of friction factor and Nusselt number from new test cases considering different geometries and flow conditions. The new coupons consisted of straight circular channels and wavy channels. This work represents a further step in the generation of a more validated and general methodology for the high-fidelity CFD analysis of AM components.
Micro-Structural Design of Soft Solid Composite Electrolytes With Enhanced Ionic Conductivity
Authors: Khodabandehloo Nastaran , Mozaffari Kosar , Liu Liping , Sharma Pradeep 
Published: January 2022

Abstract
Electrolyte in a rechargeable Li-ion battery plays a critical role in determining its capacity and efficiency. While the typically used electrolytes in Li-ion batteries are liquid, soft solid electrolytes are being increasingly explored as an alternative due to their advantages in terms of increased stability, safety and potential applications in the context of flexible and stretchable electronics. However, ionic conductivity of solid polymer electrolytes is significantly lower compared to liquid electrolytes. In a recent work, we developed a theoretical framework to model the coupled deformation, electrostatics and diffusion in heterogeneous electrolytes and also established a simple homogenization approach for the design of microstructures to enhance ionic conductivity of composite solid electrolytes. Guided by the insights from the theoretical framework, in this paper, we examine specific microstructures that can potentially yield significant improvement in the effective ionic conductivity. We numerically implement our theory in the open source general purpose finite element package FEniCS to solve the governing equations and present numerical solutions and insights on the effect of microstructure on the enhancement of ionic conductivity. Specifically, we investigate the effect of shape by considering ellipsoidal inclusions. We also propose an easily manufacturable microstructure that increases the ionic conductivity of the composite electrolyte by 40 times, simply by the addition of dielectric columns parallel to the solid electrolyte phase.
Integrating ultrasound education and resources within undergraduate medical education in order to Bring Ultrasound Internationally for Long-term Development (BUILD)
Authors: Prats Michael I. , Boone Kirsten Irene , Gorgas Diane , Bahner David 
Published: January 2022

Aims: At the Ohio State University College of Medicine, medical students have the option to train in ultrasound and take part in global electives where they can utilize clinical ultrasound. This presents the opportunity for medical students to engage in bidirectional sharing of medical and ultrasound knowledge in geographic regions with limited resources. We developedBringing Ultrasound Internationally for Long-term development (BUILD), a longitudinal course, to provide standardized ultrasound education to students planning to enroll in global health electives.Material and methods: This was a pilot study of the BUILD curriculum. Third-year medical students planning to complete a global health elective were invited to participate. Enrolled students completed an online curriculum, hands-on scanning, and pathology sessions, which augmented the predeparture Global Health course work. Students received two resource assessments: one to be completed by the student, and one to be completed by the on-site preceptor. Main outcomes measured were number of enrolled students, primary indications for imaging, and number of scans per-day.Results: In total, 152 students participated in the study and traveled to 22 different global sites in Low-Income Countries (LIC’s). All enrolled students completed the curriculum. Between 3 and 25 scans were performed per day and the leading indication for ultrasound imaging was obstetric and abdominal pain evaluation.Conclusions: The BUILD curriculum is a feasible construct to prepare students for using ultrasound during global electives. Students successfully performed proctored scans in a variety of settings. This format can be adopted by other institutions to further support student and global ultrasound programs.
Adjustment of fecundity and sex ratio in response to social environments in a haplodiploid mite
Authors: Weerawansha Nuwan , Wang Qiao , He Xiong Zhao 
Published: January 2022

Animals can adjust reproductive strategies in favour of corporation or competition in response to local population size and density, the two key factors of social environments. However, previous studies usually focus on either population size or density but ignore their interactions. Using a haplodiploid spider mite, Tetranychus ludeni Zacher, we carried out a factorial experiment in the laboratory to examine how ovipositing females adjust their fecundity and offspring sex ratio during their early reproductive life under various population size and density. We reveal that females laid significantly more eggs with increasing population size and significantly fewer eggs with increasing population density. This suggests that large populations favour cooperation between individuals and dense populations increase competition. We demonstrate a significant negative interaction of population size and density that resulted in significantly fewer eggs laid in the large and dense populations. Furthermore, we show that females significantly skewed the offspring sex ratio towards female-biased in small populations to reduce the local mate competition among their sons. However, population density incurred no significant impact on offspring sex ratio, while the significant positive interaction of population size and density significantly increased the proportion of female offspring in the large and dense populations, which will minimise food or space competition as females usually disperse after mating at crowded conditions. These results also suggest that population density affecting sex allocation in T. ludeni is intercorrelated with population size. This study provides evidence that animals can manipulate their reproductive output and adjust offspring sex ratio in response to various social environments, and the interactions of different socio-environmental factors may play significant roles.