bluuebunny/crossref_metadata_2025 huggingface dataset:
Tissue Perfusion and Biomarkers Assessment Following Root Coverage Procedures
Authors: Tavelli Lorenzo , Nguyen Tu , Rodriguez Maria Vera , Mancini Leonardo , Giannobile William V. , Barootchi Shayan
Published: January 2025

Aim

To assess tissue perfusion changes and wound healing biomarker levels after root coverage procedures with coronally advanced flap in combination with the cross‐linked xenogeneic collagen matrix (CCMX), loaded either with a placebo or recombinant human platelet‐derived growth factor‐BB (rhPDGF).

Methods

This study was designed as a secondary analysis from a previously published clinical trial, and it assessed the tissue perfusion changes over 6 months around multiple gingival recession defects, treated with either with CCMX alone (control) or with CCMX + rhPDGF (test). High frequency Doppler ultrasonography (HFUS) scans were obtained at sites of interest at baseline, 2 weeks, 3 months, and 6 months after surgery. Dynamic tissue perfusion measurements (DTPMs) were performed at the midfacial, interproximal, and transverse aspects of the teeth by an operator, blinded to treatment allocation, using a software package. The expression of different wound healing biomarkers from the gingival crevicular fluid was also assessed.

Results

The regression analyses showed similar tissue perfusion changes between the two groups throughout the majority of the 6 months. DTPMs at 2 weeks showed the test group to have significantly higher perfusion relief intensity (pRI, p < 0.001), mean perfused area (pA, p < 0.001), mean blood flow intensity (FImean, p = 0.021), and total blood flow intensity (FItot, p = 0.021) at the graft region of interest (ROI) compared to control sites. The test sites also exhibited significantly greater pA (p = 0.033) and blood flow intensity “blue” (FIblue, meaning flow away from the transducer, p = 0.035) at the level of the flap compared to the control sites. At 2 weeks, FIblue of the graft was directly correlated with the final mean root coverage (p = 0.008) and complete root coverage (p = 0.003). FImean and FItot of the graft exhibited a direct correlation with volume gain at 6 months (p = 0.031 for both parameters). The final GT gain was correlated to the early DTPMs (pA and FIblue) of the graft and the flap. The two groups exhibited different expressions of IL‐1β, PDFG‐BB, and VEGF over 3 months, with the 1‐week levels of PDGF‐BB that were associated with time to recovery.

Conclusions

HFUS allowed exquisite assessment of tissue perfusion occurring at the entire surgical reconstructive regions and also within the flap and the graft. Sites treated with CCMX + rhPDGF exhibited higher DTPMs, primarily within the graft and flap ROIs at the 2‐week timepoint compared to sites augmented with CCMX + saline. Early DTPMs at the graft and flap ROIs showed associations with PROMs and the final clinical outcomes.

Trial Registration: ClinicalTrials.gov: NCT04462237
Non‐territorial arrangements in interwar Soviet Ukraine: The development of the judicial network for minority populations
Authors: Palko Olena
Published: January 2025

In the 1920s, in Soviet Union ethnicity became territorially institutionalised, meaning that every Soviet nationality was promised a territory of their own, either in the form of a separate or an autonomous Soviet republic, national region or a separate national town or village council (soviet). Within those national‐territorial units, the Soviet state strove to provide access to state institutions, political representation, police and judicial protection, healthcare, education and cultural opportunities in the minority language. Ukraine's minorities, however, were often linguistically assimilated and territorially dispersed, making the Bolshevik territorial solutions, with some exceptions, ill‐suited to serve the republic's non‐Ukrainian population. Using the development of judicial network for minorities in early Soviet Ukraine as a case study, this article demonstrates how in the Soviet context, non‐territorial arrangements, despite conceptual resentment, were incorporated into everyday practices in parallel with national territorialisation. By doing so, this article aims to examine some overlooked aspects of the early Soviet minorities experiment and determine a correlation between hard‐line Ukrainisation—a policy of linguistic and bureaucratic de‐Russification of the republic and minority policies. Secondly, this study aims to introduce the Soviet case into the context of non‐territorial autonomy developed and implemented throughout postwar Europe.
Stress resilience in plants: the complex interplay between heat stress memory and resetting
Authors: Staacke Tobias , Mueller‐Roeber Bernd , Balazadeh Salma
Published: January 2025

Heat stress (HS) poses a major challenge to plants and agriculture, especially during climate change‐induced heatwaves. Plants have evolved mechanisms to combat HS and remember past stress. This memory involves lasting changes in specific stress responses, enabling plants to better anticipate and react to future heat events. HS memory is a multi‐layered cellular phenomenon that, in addition to epigenetic modifications, involves changes in protein quality control, metabolic pathways and broader physiological adjustments. An essential aspect of modulating stress memory is timely resetting, which restores defense responses to baseline levels and optimizes resource allocation for growth. Balancing stress memory with resetting enables plants to withstand stress while maintaining growth and reproductive capacity. In this review, we discuss mechanisms and regulatory layers of HS memory and resetting, highlighting their critical balance for enhancing stress resilience and plant fitness. We primarily focus on the model plant Arabidopsis thaliana due to the limited research on other species and outline key areas for future study.
The splicing auxiliary factor OsU2AF35a enhances thermotolerance via protein separation and promoting proper splicing of OsHSA32 pre‐mRNA in rice
Authors: Liu Jianping , Li Xin , Wang Ke , Wang Tao , Meng Yang , Peng Zhi , Huang Jinli , Huo Jiaohan , Zhu Xiaoqi , Yang Jinyong , Fan Yongxi , Xu Feiyun , Zhang Qian , Wang Zhengrui , Wang Ya , Chen Hao , Xu Weifeng
Published: January 2025

Heat stress significantly impacts global rice production, highlighting the critical need to understand the genetic basis of heat resistance in rice. U2AF (U2 snRNP auxiliary factor) is an essential splicing complex with critical roles in recognizing the 3′‐splice site of precursor messenger RNAs (pre‐mRNAs). The U2AF small subunit (U2AF35) can bind to the 3′‐AG intron border and promote U2 snRNP binding to the branch‐point sequences of introns through interaction with the U2AF large subunit (U2AF65). However, the functions of U2AF35 in plants are poorly understood. In this study, we discovered that the OsU2AF35a gene was vigorously induced by heat stress and could positively regulate rice thermotolerance during both the seedling and reproductive growth stages. OsU2AF35a interacts with OsU2AF65a within the nucleus, and both of them can form condensates through liquid–liquid phase separation (LLPS) following heat stress. The intrinsically disordered regions (IDR) are accountable for their LLPS. OsU2AF35a condensation is indispensable for thermotolerance. RNA‐seq analysis disclosed that, subsequent to heat treatment, the expression levels of several genes associated with water deficiency and oxidative stress in osu2af35a‐1 were markedly lower than those in ZH11. In accordance with this, OsU2AF35a is capable of positively regulating the oxidative stress resistance of rice. The pre‐mRNAs of a considerable number of genes in the osu2af35a‐1 mutant exhibited defective splicing, among which was the OsHSA32 gene. Knocking out OsHSA32 significantly reduced the thermotolerance of rice, while overexpressing OsHSA32 could partially rescue the heat sensitivity of osu2af35a‐1. Together, our findings uncovered the essential role of OsU2AF35a in rice heat stress response through protein separation and regulating alternative pre‐mRNA splicing.
Confocal Reflectance Microscopy Findings in Juvenile Xanthogranuloma: Report of 2 Cases
Authors: Midani Lynn , Park Katherine , Stepenaskie Shelly , Smidt Aimee C. , Durkin John R.
Published: January 2025

Juvenile xanthogranuloma (JXG) is the most common type of non‐Langerhans cell histiocytosis and is characterized by a benign proliferation of dermal dendrocytes. We report two children diagnosed with JXG with reflectance confocal microscopy (RCM), a noninvasive imaging technology that allows for multi‐layer visualization of the skin. This report demonstrates the emerging role of RCM as a painless diagnostic aid for JXG and other cutaneous diseases in children.
The branched‐chain amino acid‐related isoleucic acid: recent research advances
Authors: Mekonnen D. W. , Ghirardo A. , Zhang W. , Schäffner A. R.
Published: January 2025

Isoleucic acid (ILA) was identified in human patients with maple syrup urine disease (MSUD) half a century ago. MSUD patients, who are defective in the catabolism of branched‐chain amino acids (BCAAs), that is, isoleucine, leucine, and valine, have urine with a unique maple syrup odour related to the accumulation of BCAA breakdown products, largely 2‐keto acid derivatives and their reduced 2‐hydroxy acids including ILA. A decade ago, ILA was identified in Arabidopsis thaliana. Subsequent studies in other plant species indicated that ILA is a ubiquitously present compound. Since its identification in plants, several efforts have been made to understand the biological significance and metabolic pathway of ILA. ILA plays a positive role in plant signalling for defence responses against bacterial pathogens by increasing the abundance of salicylic acid aglycone through competitive inhibition of SA deactivation by glucosylation. Here, we review recent progress in the characterization of ILA biosynthesis and function in plants and discuss current knowledge gaps and future directions in ILA research.
Motivations for Abortion or Continuation of an Unwanted Pregnancy: A Scoping Review of the Global Literature
Authors: Beumer Wieke Y. , Reilingh Annemarie Y. A. M. , Dalmijn Eline , Roseboom Tessa J. , van Ditzhuijzen Jenneke
Published: January 2025

Context

The aim of this scoping review was to provide an overview of recent studies in peer reviewed journals investigating self‐reported motivations to have an abortion or to continue an unwanted pregnancy in different countries and settings, including both qualitative and quantitative results.

Methods

We searched for English language publications published between 2008 and 2023 indexed in four scientific databases. We included studies if they captured people's own motivations for abortion and/ or for continuing an unwanted pregnancy.

Results

Of the included 19 studies, all focused on abortion, and four also included motivations to carry an initially unwanted pregnancy to term. Motivations for abortion often related to family planning (e.g., complete family, no desire for children, not the right time), the relationship with the person involved in the pregnancy, and life or material circumstances (such as financial resources, housing or future plans), and sometimes with stigma, shame, or expected negative reactions. Motivations to continue an unwanted pregnancy were having a supportive partner and personal beliefs about the pregnancy. Despite different settings, different methods, and methodological limitations, studies showed similar multifactorial and interrelated motivations in decision making around unwanted pregnancies.

Conclusions

This research showed that in different places throughout the world multiple interrelated motivations play a role in a decision to have an abortion or to continue an unwanted pregnancy. The findings mainly provide insight into retrospective explanatory accounts, which may be biased because respondents may feel the need to justify their choice. Future research should discontinue asking people to rationalize unwanted pregnancy decisions.
Liveable, but for Whom? – Perceived Liveability and Citizen Participation in Amsterdam's Red‐Light District
Authors: Basak Oishika , van Liempt Ilse
Published: January 2025

Popularly known as Amsterdam's Red‐Light District, De Wallen is one of the Netherlands' most well‐known yet controversial areas. This politicised neighbourhood has witnessed years of gentrification and touristification. Many contemporary debates concerning De Wallen, and the municipality's policy interventions have been around the topic of liveability. This case study examines the neighbourhood's liveability from the eyes of diverse local stakeholders and analyses how their perceptions of liveability get reflected, or not, in the citizen participation mechanisms. De Wallen's stakeholders, apart from the municipality, include residents, business owners, sex workers, socio‐cultural institutions, and employees of various establishments. By interviewing some of these diverse voices, the study highlights the plurality in the liveability perceptions of the local stakeholders. Thus, this research builds onto existing theoretical and empirical work by underscoring the importance of analysing liveability from a contextual lens and evaluating whose liveability perceptions are given primacy while creating policies for an urban area.
A congruence theorem for compact embedded hypersurfaces in S+n+1$\mbox{${\mathbb {S}}$}^{n+1}_+$
Authors: Freitas Allan , Guimarães Felippe
Published: January 2025

We prove a codimension reduction and congruence theorem for compact ‐dimensional submanifolds of that admit a mean convex isometric embedding into using a Reilly‐type formula for space forms.
HUVER: The HyForm Uncrewed Vehicle Engineering Repository
Authors: Karri Abhiram , Stump Gary , McComb Christopher , Song Binyang
Published: January 2025

This paper introduces the HyForm Uncrewed Vehicle Engineering Repository (HUVER), a comprehensive multi-modal dataset of uncrewed aerial vehicle (UAV) designs, complete with performance evaluations, derived from the HyForm UAV design testbed. The dataset includes 6,051 unique UAV configurations, each represented using strings adhering to a designed grammar, images, 3D mesh models, and textual descriptions, alongside performance metrics obtained from physics-based simulations. Designed to support data-driven and AI-driven design processes, one area in which this dataset can facilitate research is the surrogate modeling and generative design of UAVs, providing a resource for developing predictive models and supporting human-AI collaboration in UAV design. The dataset adheres to FAIR principles, ensuring it is retrievable, accessible, interoperable, and reusable, and is made available as an online repository for ease of use by the research community.
Optimal Synthesis of Zero-Stiffness Compliant Mechanisms Based on Potential Energy Principle
Authors: Li Zewei , Jin Mohui , Wang Weisheng , Qu Mingyu , Xu Xing
Published: January 2025

Zero-stiffness compliant mechanisms (ZSCM) can provide constant or zero force over a range of motion without the issues caused by the inherent stiffness of compliant mechanisms (CM). The large-deflection curved beams in ZSCM enhance the mechanism’s performance but pose significant modeling challenges. As an effective method for modeling curved beams, chained pseudo-rigid-body model (CPRBM) can be an intuitive method to implement in ZSCM synthesis. However, its difficulty in solving reaction forces limits its usability in the frequently-used force-based ZSCM synthesis. To address the problem, this article proposes an energy-based method for CPRBM-based ZSCM synthesis, without calculating the reaction force. This method synthesizes the mechanisms with zero-stiffness characteristics by optimizing the energy recorded from the analysis based on the principle of minimum potential energy. Two optimization models based on energy characteristic are developed for constant force CM (CFCM) and statically balanced CM (SBCM), respectively. Synthesis cases and experimental studies are used to verify the proposed method. The results demonstrate that the synthesized ZSCM have good performances and the proposed method can be a user-friendly tool for ZSCM synthesis.
Design of Multi-Agent Systems Based on Bilevel Closed-Loop Planning
Authors: Cao Jinhui , Ming Zhenjun , Allen Janet K. , Mistree Farrokh
Published: January 2025

Advanced multi-agent systems are capable of executing tasks in complex and unknown domains that are unsuitable for humans. However, the design of multi-agent systems faces challenges in balancing global and local decision-making and enabling the system to adaptively generate desired behaviors in a dynamic environment. To address these challenges, in this article, we propose a multi-agent system design framework based on bilevel closed-loop planning. We use the multi-agent box-pushing problem as an example to verify the framework. Within this framework, the upper-level planning (which is used for box position prediction) and the lower-level planning (which is used for agent position allocation) are designed to connect and coordinate between the global and local decisions. The influence of states based on planning creates a closed-loop control mechanism with temporary targets as input, allowing the system to adapt to various environments. In this article, we use webots as the simulation platform to conduct multi-agent box-pushing experiments and compare the results with the rule-based method to demonstrate the effectiveness and advantages of our approach.
Enhancing Bayesian Inference-Based Damage Diagnostics Through Domain Translation With Application to Miter Gates
Authors: Zeng Yichao , Zhao Zhao , Qian Guofeng , Todd Michael D. , Hu Zhen
Published: January 2025

Bayesian inference based on computational simulations plays a crucial role in model-informed damage diagnostics and the design of reliable engineering systems, such as the miter gates studied in this article. While Bayesian inference for damage diagnostics has shown success in some applications, the current method relies on monitoring data from solely the asset of interest and may be affected by imperfections in the computational simulation model. To address these limitations, this article introduces a novel approach called Bayesian inference-based damage diagnostics enhanced through domain translation (BiEDT). The proposed BiEDT framework incorporates historical damage inspection and monitoring data from similar yet different miter gates, aiming to provide alternative data-driven methods for damage diagnostics. The proposed framework first translates observations from different miter gates into a unified analysis domain using two domain translation techniques, namely, cycle-consistent generative adversarial network (CycleGAN) and domain-adversarial neural network (DANN). Following the domain translation, a conditional invertible neural network (cINN) is employed to estimate the damage state, with uncertainty quantified in a Bayesian manner. Additionally, a Bayesian model averaging and selection method is developed to integrate the posterior distributions from different methods and select the best model for decision-making. A practical miter gate structural system is employed to demonstrate the efficacy of the BiEDT framework. Results indicate that the alternative damage diagnostics approaches based on domain translation can effectively enhance the performance of Bayesian inference-based damage diagnostics using computational simulations.
A Micro-Deformation Model of Parallel Manipulators in the Gravity Field
Authors: Yang Chao , Yu Wenyong , Quan Fei , Ye Wei , Lu Yebo
Published: January 2025

Establishing a microelastic deformation (micro-deformation) model of parallel manipulators (PMs) in the gravity field is of great significance for improving the calibration accuracy. Gravity affects the limb constraint wrenches space of PMs, resulting in the end-point micro-deformation, which damages end-point accuracy. A modeling method was proposed for the micro-deformation analysis of PMs with the consideration of gravity and the flexibility of rods and actuators based on the screw theory to fix this issue. First, the mechanism was considered an open-loop structure by cutting joints at the connection between limbs and moving platform. The limb constraint wrenches system and limb stiffness matrix were determined based on the screw theory and strain energy methods. Then, the limb gravity-additional constraint wrenches induced by gravity were established based on the reciprocity product of the twist screw and the constraint wrenches being zero. Meanwhile, the projection of limb deformations caused by gravity in the direction of the constraint wrenches system was established. Finally, an analytical methodology of the end-point micro-deformation of PMs with the consideration of gravity was built by means of the virtual work principle. The work decoupled the influences of gravity and the external load on the micro-deformation of the mechanism. The comparison between the results of the analytical model and finite element model of the line body and solid body of the 3PRRR over-constrained PM showed that the maximum error of the linear micro-deformation was within 3% and 11%, respectively.
Effect of Temperature on the Dynamics of Metamaterial Structures: Experimental Analysis
Authors: Pellicano Francesco , Cannillo Valeria , Iarriccio Giovanni , Molaie Moslem , Zippo Antonio
Published: January 2025

In this study, we investigate the vibrational characteristics of honeycomb structures crafted from metamaterials through experimental means. Specifically, we focus on plate structures composed of honeycomb, utilizing 3D printing to fabricate specimens with chiral properties and a negative Poisson ratio in their cores. The objective is to assess the dynamic behavior, such as the natural frequencies and damping, and their dependence on the temperature. The core layers were 3D printed and constructed from polylactic acid (PLA). Two different core patterns were explored to determine the eventual differences in terms of dynamic features. The experimental campaign involves impact hammer testing and sinusoidal excitation. The former are intended to identify natural frequencies and mode shapes, the latter are conducted on a shaking table within a climate chamber to replicate realistic environmental conditions. Indeed, the temperature significantly influences the elastic and dissipative features of the materials, as well as the specific behavior of metamaterial patterns.
Study on the Influence of Worn Rail on Subway Wheel Wear Prediction Based on Iteration Dynamics Simulation
Authors: Yin Zheng , Lu Zhenggang , Jing Zhipeng , Wei Juyao
Published: January 2025

A certain type of subway vehicle was examined in this paper. Based on the measured worn rail profiles on the curve, a vehicle dynamics model of this type of subway was established. The evolution of wheel wear during vehicle-on-curve motion was obtained via iterative dynamics simulation. The effect of abrasive rails on the wear of subway wheels was investigated. The simulation results show that when significant wear occurs on the rail profile on the curve, although the difference in the wear volume rate under different operating conditions reaches 82.95%, the difference in the average wear volume during the whole operation is only 23.78%. Therefore, it is necessary to propose a model for updating rail profiles in wheel wear prediction simulations. This paper proposed a measure of the influence of rail profiles on wheel wear distribution based on the Manhattan distance and correlation coefficient and a rail profile update model and used iterative dynamics simulation to comprehensively evaluate the influence of rail wear on subway wheel wear on curves. Research results show that the rail profile updating method proposed in this paper can significantly improve the accuracy of wheel wear prediction in the simulation of wheel wear prediction, especially when the wheel pair is operated on worn rails after reprofiling.
Comparison of Laminar and Turbulent K-Omega Shear Stress Transport Models Under Realistic Boundary Conditions for Arterial Stenosis
Authors: Al-Rawi Mohammad , Belkacemi Djelloul , Al-Jumaily Ahmed M.
Published: January 2025

Early diagnosis of cardiovascular diseases (CVDs) is critical to target treatments that reduce CVD mortality. Improving the accuracy of early diagnostic tools is, therefore, a key goal for biomedical scientists and engineers. Arterial stenosis is one form of CVD for which effective, non-invasive early diagnosis is invaluable. Current studies concerning the computational and numerical assessment of stenosis indicators use different mathematical models, such as laminar and k-omega shear stress transport (SST) models. These models are available in several software packages, such as ANSYS (Fluent and CFX), OpenFOAM, and COMSOL. These packages allow the users to set different boundary conditions, such as velocity at the inlet and pressure at the outlet and create user-defined functions (UDFs) with different expressions and constant values. However, there currently needs to be a rule over what to impose at these boundaries. Furthermore, previous studies have used various assumptions, such as rigid artery wall, one-way fluid-structure interaction (FSI) or two-way FSI, and the blood’s Newtonian or non-Newtonian material properties. This variety in construction has associated deviations of the models from the clinical data and lessens the value of the models as potential diagnostic or predictive tools for medical practitioners. In this study, we examine stenosis of increasing severity, presenting first a healthy artery and then three arteries with stenosis of 20%, 40% and 50%, analysing in terms of the strain energy to the artery wall based on the propagated waveforms through the arteries under the different arterial diameters. Many current studies use rigid walls and zero pressure boundary conditions at the outlet using a laminar or k-omega SST model. In this study, we investigate elastic walls using the one-way FSI concept and the pressure waveform at the outlet, comparing the results across the two common methods of laminar and k-omega SST. These velocity and pressure waveforms are provided as an expression based on clinical data. The results regarding the strain energy (mJ) behaviour along the artery wall show that the k-omega SST model outperforms the laminar model for short arterial segments and under the Newtonian assumption with a no-slip boundary wall and turbulent flow.
Revisiting the Flow Instability of Shrouded Corotating Disk Systems
Authors: Watanabe Akira , Obi Shinnosuke
Published: January 2025

In disk drive systems, flow-induced vibration, often attributed to turbulent fluid motion, presents a significant challenge due to its wide-ranging frequency spectra. Helium-filled enclosures have been introduced to mitigate this issue by reducing the force exerted by fluid motion, owing to the lower gas density compared to air. This density reduction leads to a decrease in the inertia force relative to the viscous force, lowering the Reynolds number by nearly an order of magnitude and resulting in an anticipated transition from turbulent to laminar flow. However, the transitional regime poses challenges, potentially causing intermittently alternating flow motion between turbulent and laminar states, characterized by velocity fluctuations of larger magnitude. Our experimental study involved a series of tests with a system comprising five 3.5-inch disks enclosed within a cylindrical casing. Varying the disk rotation speed from 600 rpm to 7200 rpm resulted in Reynolds numbers ranging from about 1 × 104 to 1 × 105. While air-filled configurations consistently exhibited fully turbulent flow, helium-filled setups demonstrated laminar characteristics at lower Reynolds numbers. Our findings suggest transitional behavior at intermediate Reynolds number ranges, indicating a shift from stable to unstable flow patterns. These observations underscore the potential challenges associated with helium-filled disk systems.
Industry 4.0 and Modernizing Manufacturing Education
Authors: Singh Pooja Thakkar , Pothier Debra Ann , Sethupathy Anand , Gooding Geraldine , Soukup David , Reich Jarrett , Lamarre Morgan , Warrick James Stewart
Published: January 2025

Industries are encouraged to work together to reduce the time to talent, or the period when an employee transitions from entry-level to being able to effectively contribute to achieving the organization’s goals. This paper guides the integration of an Industry 4.0 curriculum into two- and four-year institutions, focusing on essential topics like design for manufacturing, sustainability, and generative design. ASME and Autodesk propose a modular approach with core themes, case studies, real-world examples, self-assessments, videos, and hands-on exercises. This structured methodology aids professors in seamlessly incorporating Industry 4.0 concepts into their classrooms, preparing the next generation of engineers for modern manufacturing challenges.
Analysis and Simulation of Two-Dimensional Dual-Arm Manipulator for Baseball Training
Authors: Limata Kyler , Hu Qinfu , Duan Shawn
Published: January 2025

The use of robotic arms with multiple degrees of freedom has increased significantly over recent decades, finding applications across various sectors. However, their potential in sports training, particularly in baseball pitching to assist catcher training, remains largely unexploited. This study explores the feasibility of employing two-dimensional, two-degree-of-freedom robotic manipulators for pitching baseballs, focusing on the dynamic capabilities necessary for such tasks.

The simulation model, developed in Autolev and implemented in MATLAB, represents a dual-link robotic arm with joints exerting torques ranging from 10 to 20 Nm. The analysis covers four simulations of half-second durations to assess the high-speed movement capabilities of the manipulator. Additional simulations with zero applied torques provide insights into the inherent dynamics of the system.

Drawing from Bauml et al.’s (2010)[1] work on dynamic, dexterous manipulations, this study integrates computational optimization to enhance our understanding of the multibody dynamics involved in tasks such as catching a moving baseball. The findings suggest that such robotic manipulators can effectively mimic the high-speed pitching actions required in baseball, underscoring their potential utility in sports training applications. This research lays the groundwork for further exploration into robotic manipulators in dynamic sporting tasks, opening new pathways for advancements in robotic automation and high-speed object interception.
Modeling NO2 Emissions From Biomass Gasification: an Examination of a Case in the Rural Community of Batata, Located in the Municipality of Tierralta, Córdoba, Colombia
Authors: Tavera Quiroz Humberto Carlos , Mendoza Fandiño Jorge Mario , Pinto Argel Samuel David , Hernández Sibaja Gerardo Cusi , Pérez Peñate Ana Karina , Coronado Arango Angélica Aideé , Gómez Vásquez Rafael David , Arrieta Almario Álvaro Ángel
Published: January 2025

This study focuses on modeling NO2 emissions, from a residual biomass gasification plant in Batata, Tierralta, Córdoba, Colombia. It employs a methodology that integrates emission source analysis through stoichiometric calculations and mass balances. Meteorological conditions are determined using data from the NASA POWER® satellite and IDEAM stations. Given the need for accuracy in air pollution modeling, the Aermet View® software is used to obtain and validate one-year hourly meteorological data. These outputs serve as inputs for the AerMod View® model to simulate dispersion patterns and analyze NO2 concentrations.

Simulation results indicate that the highest NO2 concentrations are localized around the gasification activity area. However, these concentrations remain within the permissible standard of 200 μg/m3. Further analysis suggests minimal health risks to the local population, as concentrations within the town center comply with safety standards. On an annual basis, the study finds that concentrations do not surpass the 60 μg/m3 threshold.

The study’s findings underscore the environmental feasibility of establishing a biomass gasification plant and highlights the project’s potential to contribute to waste management and energy production in isolated communities. Furthermore, the research emphasizes the importance of adopting sustainable practices aligned with both environmental and public health objectives.
Further Insights in the Dynamic Analysis of Parametrically Excited Stable Rotors With Unbalance: Shear and Gyroscopic Effects
Authors: De Felice Alessandro , Sorrentino Silvio
Published: January 2025

This study, following a previous investigation by the same authors, deals with unbalance effects in the stable domain of a slender rotor parametrically excited by an axial end thrust, considering in addition, as a novel contribution, the effects of shear deformation and gyroscopic actions. Unbalance causes a harmonic load acting on flexural deflection, influencing the response together with the parametric excitation, yielding a sequence of combination external resonances, also affecting the critical speeds of the rotor. A distributed-parameter model is adopted, consisting of a homogeneous Euler-Bernoulli straight beam spinning at constant angular speed on isotropic supports, unbalanced and loaded by an axial end thrust with a harmonic time-dependent component. Shear deformation and gyroscopic effects are studied separately, by considering additional terms in the Euler-Bernoulli model, either the Euler-Bernoulli beam model plus shear or the Rayleigh beam model. The flexural response is investigated in the frequency domain by decoupling the dynamic equilibrium equations in exact and approximate forms, yielding scalar non-homogeneous Mathieu equations.
A Study on Structural Safety Evaluation Technology for Separately Assembled Radiators With a Transformer
Authors: Yun Minok
Published: January 2025

In transformers, radiators are heat exchangers which are used to maximize heat dissipation from the transformer oil to the external cooling medium. Radiators are usually installed on transformers in two ways. The first way is mounting directly to the transformer tank wall. The second way is installing separately from the transformer. It is called the separate radiators assembly. In this paper, equations were derived in order to select the optimal length of base plates of a separate radiators assembly to prevent rollover. Additionally, wind forces were calculated based on the SBC (Saudi Building Code) standard that has the most structurally harsh conditions. Power transformers and separate radiators assemblies are installed primarily in open, flat areas with no other buildings nearby. Therefore, they should be evaluated for structural safety against wind loads from the surrounding area. Then, analysis based on numerical method of real separate radiators assembly were conducted to verify structural safety. As a result, the optimal length of base plates of a separate radiators assembly and the design improvement of a separate radiators assembly considering their allowable stress was derived to secure the structural safety again the wind force. Through this process, the evaluation technology suggested in this paper was validated.
Thermal Energy Harvesting of Tree Trunk for Low-Wattage Electronic Applications Using Modular Design of Thermoelectric Generators
Authors: Le James , Jackson Kraig , Kim Hee-Seok
Published: January 2025

Thermoelectric generators (TEGs) have a wide range of prospective applications in environmental monitoring, particularly for generating low-yield power. Extracting energy from the difference in temperature between a tree’s internal temperature and the surrounding air offers a reliable and low-maintenance method to power sensors and other small electronic devices. The primary focus of this study is on modularity and stacking of multiple stages by advancing the previous harvester prototype. This design enables the harvester to efficiently utilize the thermal energy from tree trunks. The prototype unit with a diameter of 2 inches in 1.25 inch thick has a predicted output power generation of 62.4 milliwatts from two commercial TEGs in the unit, using a numerical model that incorporates both n-type and p-type thermoelectric components. The material properties of Bi2Te3 at room temperature are used to calculate the thermal behavior of the material for a certain temperature difference. It is assumed that these material properties remain constant within the operational temperature range.
Flow Regimes in a Rotating Multi-Cylinder Filter
Authors: Bohling Sean K. , Huang Jiayang , Dressaire Emilie
Published: January 2025

Aquatic organisms rely extensively on hair-covered surfaces for chemical sensing and feeding functions. Suspended food particles are filtered out of the water and ingested. This filter-feeding strategy avoids the challenges of engineered filters, whose efficiency decreases dramatically until they need to be replaced. These biological hair-covered surfaces, therefore, provide a novel approach to filtration.

The flow through hair-covered surfaces has traditionally been studied with a macroscopic array of rigid hairs in a long flow channel. Flow through such finite porous medium exhibits three regimes, with increasing fluid transport through the array: rake, deflection, and sieve. In the rake regime, the bulk flow is diverted around the array, while in the sieve regime, the flow goes through the array. The deflection regime is a transition regime where some of the streamlines exit the array laterally. The regimes depend on the Reynolds number of the flow, porosity, and confinement of the array. The channel geometry is a model configuration to study transport. Yet, the geometry limits the volume of fluid that can be filtered. We consider a rotating hair-covered surface in a cylindrical tank to increase the throughput. The rotating array is a closer approximation to the flow seen by aquatic creatures such as crustaceans, which flick their antennules in an arc to sense their environment.

This study uses finite element analysis to characterize transport through an array of hairs swept in a circular path through stationary fluid. The 2D simulations conducted with COMSOL Multiphysics investigate low-speed flows where the Reynolds number of a hair ranges from 0.001–40. This flow condition has a velocity profile that linearly increases from the inner to the outer edge of the array. To study the influence of the flow geometry on the three regimes, we vary the rotational velocity and array dimensions. We measure the flow rate entering through the first row and the drag on the hair array. These measurements allow the definition of the three regimes and the efficiency of the filtration process. The filter efficiency increases with the volume of fluid entering the array and decreases with the drag on the array. The filtered volume and drag coefficient exhibit a non-linear dependence on the rotation speed. In the first part of the proceedings, we discuss the conditions under which each regime is observed. In the second part of the proceedings, we address how drag on the array affects filtration efficiency. Finally, we conclude with design guidelines for hair-based high-efficiency filters.
Energy Conversion Performance Comparison of Two Radial Flux Dual Rotor Motors for Direct-Drive Electric Vehicles
Authors: Yan Kehan , Hu Zunyan , Li Jianqiu , Xu Liangfei
Published: January 2025

Direct-drive configurations in electric vehicles (EVs) offer a shortened power transmission path but introduce challenges related to torque, volume, weight, and efficiency. Dual and double rotor motors (DDRMs) are emerging as potential solutions to these issues. However, the evaluation of flat winding technology in these motors remains nascent, delaying extensive research. This study provides a retrospective analysis of the energy performance of series flux double rotor motors (SFDRM) and parallel flux dual rotor motors (PFDRM). It examines their operating principles and performance characteristics, focusing on the comparative analysis of flux paths between SFDRM, PFDRM, and outer rotor integral slot motors (ORISM). This study explains that the output torque of DDRM is higher than that of ORISM in potential. Our findings indicate that variations in stator yoke height and slot tooth width are significantly influenced by the differing flux sharing paths of SFDRM and PFDRM. Additionally, the number of poles plays a critical role in defining flux path groups, which affects the output torque and efficiency. SFDRM with 56 or higher poles stands out, offering superior torque volume density, weight density, and operational efficiency.
Oxygen Delivery System for Closed-Circuit Escape Respirators
Authors: Fernando Rohan D. , Toole Brian W. , Cornman Jacob K.
Published: January 2025

In the design of self-contained closed-circuit escape respirators (CCERs), using the closed-circuit principle where the breathing gas from the user is recirculated and reconditioned in a closed loop within the apparatus is the most efficient design and leads to a small size. This type of respirator is favored when it must be carried by the user at all times for quick deployment in an emergency. A unique oxygen delivery system (ODS) that is compact and operates at a very high pressure for these type of respirators was developed. This ODS comprises a carbon composite cylinder storing pure oxygen, a valve integrated pressure reducer (VIPR), and a demand valve that delivers the breathing gas to the user. To minimize the physical size while retaining the performance characteristics required, direct metal laser sintering was used for the VIPR body using metal alloys and very high oxygen pressures of up to 10,000 PSI. This paper outlines the design, function, testing, and performance of the ODS. Unique design features were developed and incorporated such as delayed pressurization of the high-pressure chambers within the VIPR to reduce its size and eliminate leak paths. Overall, the flow characteristics of the VIPR and the system work of breathing performance were adequate and met the design requirements for the ODS. Applied in a future design, this ODS should contribute to development of smaller CCERs than current devices and deliver oxygen according to Title 42 Code of Federal Regulations.
Analysis and Design Improvements for an Between-Car Barrier Failure on Urban Rail Transit Vehicles
Authors: Zhang Long , Yin Yanbo , Chen Qiubo , Wu Zijing , Feng Baide , Cao Yanhua , Wu Lvxian , Lu Peng
Published: January 2025

This paper presents the failure analysis and design improvement measures following a recent between-car barrier (BCB) entanglement incident involving two urban rail transit (URT) vehicles, where the BCB is a safety-critical component bridging the potentially dangerous gap between coupled vehicles mandated by ADA regulations.

Through a fault tree analysis (FTA), two possible factors were identified: the changes in the safety strap properties due to prolonged operation time, and extreme rail conditions encountered during mainline/yard operations. Results of the material analysis and aging tests ruled out UV exposure and material elongation as significant contributing factors. Further analysis focused on BCB interactions under various rail track conditions. Several Design of Experiments (DOE) were devised and analyzed, revealing specific scenarios where entanglement could occur. With the root cause identified, FEA simulations and design iterations led to a retrofit solution, including the addition of a diagonal guiding rod and extra precautions on the safety straps.

By sharing this case study, the paper aims to provide insights from the design experience of a kind of BCB for URT trains and offer valuable lessons learned on corner cases for future vehicle designs.
Characterization of Deposited Dust on PV Panels and Residual Dust After Cleaning With an Electrostatic Device
Authors: Albaradi Abdurahman , Mynderse James A. , Zhou Meng
Published: January 2025

Dust accumulation on the surfaces of photovoltaic (PV) panels reduces the power output over time. Therefore, cleaning PV modules is essential to ensure the maximum energy yield. While solar energy is widely available in arid and semi-arid locations with high irradiance, such as Saudi Arabia, these regions are more prone to dust deposition and necessitate PV cleaning. Due to the arid climate, water-free PV cleaning methods are of particular interest. This study analyzes five soil samples from around potential PV power plants locations in Saudi Arabia. The dust particles were analyzed for size distribution, shape, elemental composition, and chemical composition. After thorough cleaning with electrodynamic shields (EDS), the residual dust was collected and characterized in the same manner as the original samples. The residual dust generally consisted of small (< 20 μm) and large (> 80 μm) particles outside the EDS effective cleaning range of 20–80 μm. The mineral compositions of the residual dust had a relative permittivity lower than the deposited dust.
Investigating the Effects of Polymer Particle Shape and Impact Orientation in Cold Spray Additive Manufacturing
Authors: Duran Salih , Kokal Uğur , Özdemir Ozan Çağatay , Müftü Sinan
Published: January 2025

Impact of non-spherical polymer particles on polymer substrates is investigated to analyze the effects of particle shape and incidence angle for polymer cold spray applications. We focused on different polymer particle-polymer substrate combinations, such as polystyrene-block-polydimethylsiloxane and high-density polyethylene, and developed temperature and strain rate-dependent material models for each material. Results showed that the initial shape of the polymer particles has a significant effect on their behavior during impact. Particles with 0.2 flattening value show a 75% reduction in effective strain energy release rate and 37.5% decrease in coefficient of restitution. We also investigated the effects of size and orientation and found that each particle size is similarly sensitive to shape effects, with smaller particles showing a lower effective strain energy release rate and higher bonding probability. Investigation of high-density polyethylene revealed that the shape effect decreases with increased ductility. Overall, this study provides insights into the fundamental behavior of polymer particles during cold spray additive manufacturing and highlights the importance of considering particle shape and incidence angle for improved process optimization.