bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Areal Surface Topography on Thermal Oxidation of Ti6Al4V
Authors: Murwamadala Rabelani Dennis , Veeredhi Vasudeva Rao 
Published: February 2024

Abstract
A simple way to improve and optimize the mechanical properties of a metals surfaces’ is by using a suitable heat treatment. In the case of heat treatment of Ti-6Al-4V alloy, heat treatment alters its areal surface topography. In this study, samples of Ti-6Al-4V alloys are prepared with varying roughness are treated at 750 °C at varying time durations. The treated surfaces were then measured using a laser confocal microscope, and data was processed in the Confomap software. The software has advanced analyses modules useful for real-time quick analysis of topological data. The study explores the topological changes caused by heat treatment using these advanced modules. The changes in surface, functional parameters, directionality, isotropy, and areal spectral properties are summarized and reported. The results show a direct correlation between these surface changes, initial surface properties, and the treatment duration. The results show a significant change in the two-hour treatment for all measured parameters except the areal spectral results, which significantly changed in the eight-hour treatment experiment.
Capillary Network for Fluid Access
Authors: Zhang Xuewei , Lorente Sylvie 
Published: February 2024

Abstract
The theoretical and numerical development of capillary networks for water transportation is documented here. The capillary network is made of dendritic structures connecting the sources to a sink (the outlet); water is extracted by capillary suction from those multiple random sources and the flow is conducted to one single outlet. The approach is based on the constructal law of evolutionary design. The development of the network starts with one channel, then sources are connected to the network one by one with the objective of transporting higher and higher flow rates through the network while decreasing the overall friction losses. For a fixed network volume, the capillary network generated in a plate has a higher flow rate compared to the one generated in a sphere. The average bifurcation angle from both cases which leads to a higher flow rate is 71°. The impact of the Hess-Murray’s law is discussed in the work. The higher volumetric flow rates are obtained when the radius exponent ratio between the mother and daughter channels ranges from 2 to 25 whilst the value is 3 according to Hess-Murray’s law. A transient numerical study of the capillary flow in the developed network is performed. The end of the transient regime leads to results equivalent to the ones obtained with the in-house approach, therefore validating it.
Success Factors and Barriers in Industry-Academia Collaborations - A Descriptive Model
Authors: Kempf Christoph , Hellwig Imke , Bastian Annika , Ritzer Katharina , Albers Albert 
Published: February 2024

Abstract
Companies cannot overcome the increasing complexity of nowadays cyber-physical systems alone. Thus, the industry uses academic research as an important source for gaining new knowledge and technologies. However, a successful exchange is fraught with barriers, so it is important to understand the success factors and barriers. This paper presents a model explaining the most relevant success factors and barriers to industry-academia collaborations and their relations. Based on a systematic literature review, an interview study, an online survey, and focus groups, we identified 22 relevant success factors and 22 barriers. We clustered these success factors and barriers into five categories: communication & feedback, information & (technical) support, motivation & commitment, people & team, and structure & organization. We believe that our model will help improve industry-academia collaboration’s success by raising awareness of the barriers and offering success factors as setting levers. Furthermore, our model can serve as the basis for further research of methods for and to support industry-academia collaboration. Therefore, we intend to develop a methodology for challenge-driven industry-academia collaboration.
Determine the Maximum Negative Operating and Collapse Pressure of Stocked Spiral Duct With and Without Corrugations
Authors: Harvey Justin , Walker Charles D. , Paruchuri Venkata Avinash , Idem Stephen 
Published: February 2024

Abstract
This paper describes an experimental program to experimentally determine the extent to which incorporating corrugations in spiral ducts increased their strength, thus permitting operating and collapse pressures that were higher (more negative) than non-corrugated ducts of the same gauge. The presence of corrugations increased the apparent stiffness of the ducts, and therefore suppressed their tendency to deform under negative pressure. Relatively small diameter spiral seam ducts were more resistant to excessive deformations than larger diameter ducts, for a given wall thickness. At the smallest nominal duct diameters considered in this test program the negative internal gauge pressures where corrugated spiral seam ducts were likely to first exceed a prescribed deflection limit were as much as 6 to 9 times greater than the corresponding values for non-corrugated ducts of the same wall thickness. The ability to withstand the effects of negative internal gauge pressures diminished as the duct diameter increased. Little or no benefit to incorporating corrugations was observed at the largest duct diameters that were investigated. This research yielded a table of negative pressure capacity for several standard gauge spiral ducts, with and without corrugations, that will enable the estimation of maximum deflection of the ducts. This also provides guidance regarding potential collapse pressures.
Highlights of Accelerated Degradation Mechanisms for Polymer Electrolyte Fuel Cell
Authors: Ordóñez-Saca Brayan , Espinoza-Andaluz Mayken , Santana-Villamar Jordy , Andersson Martin 
Published: February 2024

Abstract
Polymer electrolyte fuel cells (PEFCs), considered green devices, use hydrogen and oxygen as reactants in electrochemical processes to produce electricity, water, and heat as by-products. The use of this technology in the automotive industry and power generation has led to a detailed study of its operating principle to make it cost-effective. Polymer electrolyte fuel cells as innovative technology has promoted research to improve its performance. For this reason, a review of the accelerated degradation methods for the membrane, the catalyst layer, the gas diffusion layer, and finally, the bipolar plates are presented. In this work, it also been found that accelerated stress test has already been standardized for cell structure in general however and on the other side there is a little research on degradation methods for bipolar plates. Finally, a brief review of the mitigation strategies has been carried out, given that with the compilation of accelerated aging in the fuel cell structures, it has been observed that the research is focused on improving materials for the use in the layers of fuel cell.
Controlling Thermal Conductivity of Composite Material – Few Large and Many Small Approach
Authors: Athadkar Meghana , Lorente Sylvie 
Published: February 2024

Abstract
Composite metal foams are made of metal matrix and air-filled spherical inclusions. They have superior mechanical and thermal characteristics when compared to the parent metals. Intrinsic material properties like thermal conductivity of composite metal foams can be controlled by distributing the porosity in the matrix based on few-large-and-many-small approach inspired by the Constructal law. To demonstrate this, large spheres in a metal foam are replaced with smaller diameter spheres, while maintaining constant porosity. It is shown that this form of redistribution of porosity results in decreased thermal conductivity of the metal foam.
Using Low-Cost Hands-On Equipment and Virtual Lab for Teaching and Learning of Mechanical Vibrations
Authors: Tran Kevin , Walker Britt , Utschig Tris , Tekes Ayse 
Published: February 2024

Abstract
Hands-on learning elevates the student’s learning of abstract topics to a new level so they will bridge the gap between the theory and its application area. Although mechanical engineering students are only exposed to hands-on learning in laboratories, students take the fundamental course separate from labs which are offered in the following semester or year, unlike mechatronics, electrical, and computer engineering students. Additionally, the laboratory equipment utilized in mechanical vibrations and control labs are very expensive and bulky and integrated with their own software preventing students to discern signal flow and data recording using sensors and data acquisition systems. To address this problem, we designed two low-cost, portable, and 3D-printed lab equipment for the mechanical vibrations control theory courses and their associated laboratories so that faculty can bring it into the classroom for a quick demonstration and build multiple of the same setups for the lab courses to demonstrate modeling of mechanical systems and fundamentals of vibrations. In addition to the developed equipment, we created a virtual lab in MATLAB Simscape so students can work on the analysis at their own pace.
Laminar Drag Reduction in Microchannels With Slippery Polymer Brush Surfaces
Authors: Sutradhar Jayanta , Fan Bei 
Published: February 2024

Abstract
Flow drag reduction plays a significant role in numerous engineering applications. Microfluidics has been studied for various important applications, such as energy conversion, microfluidic sensors, biosensing, and biomedical devices. In laminar flows in microchannels, drag reduction is capable of reducing the required pumping power, enhancing microfluidic cooling, augmenting electrokinetic energy harvesting, enabling better flow control in chemical and biological devices and etc. To reduce fluid drag, researchers have investigated different techniques which include textured slippery surfaces filled with fluid lubricant (i.e., air or oil) in their textures like superhydrophobic or slippery liquid-infused surfaces. For traditional textured slippery surfaces, to retain fluid lubricant, typically additional specific surface textures are required. However, there are two significant challenges associated with textured slippery surfaces: 1) the surface coverage of the fluid lubricant layer is often limited, restricting overall drag reduction; and 2) fluid lubricant suffers from poor durability as the lubricant layer could be depleted by the overlaying shear flow, after which the surfaces will lose their slipping property and even increases the wall friction. In recent studies, a novel type of non-textured slippery liquid-like polymer brush surface has been developed. The slippery liquid-like polymer brush surface has been demonstrated to exhibit macroscope liquid-like properties with an apparent viscosity that can be potentially smaller than that of water and can work as a fluid lubricant layer. Thus, this novel non-textured slippery liquid-like polymer brush surface represents a promising candidate for drag reduction. To investigate the drag reduction induced by the slippery liquid-like polymer brush surfaces, in this work, we fabricated microchannels with slippery polymer brush-grafted surfaces and microchannels made of silicon surfaces and measured the pressure drops along the microchannels under various flow rates and Reynolds numbers. The drag reduction coefficient and corresponding fluid slip length are calculated. The drag reduction coefficient is between 4.53% to 18.77% for Reynolds number between 5.5 to 12 and fluid slip length in micron scale is achieved.
Experimental Study of Spray Cooling Technique in Liquid Piston Gas Compression at Different Initial Pressure Levels
Authors: Ahn Barah , Ro Paul I. 
Published: February 2024

Abstract
Compressed air energy storage (CAES) is one of the promising energy storage options for renewable energy owing to its relatively small environmental impacts and economic viability. The combination of a liquid piston gas compressor and droplet injection through spray can greatly improve the efficiency of the compression stage of CAES. In the present work, the spray cooling technique in a liquid piston gas compressor at different pressure levels is experimentally tested. Gas compressions starting from 1, 2, and 3 bars with a pressure ratio of 2 were performed with and without the spray method, and the impacts of the initial pressure level on compression efficiency were evaluated. The spray technique showed about 98–98.5% isothermal efficiencies for all three pressure levels, which are substantial improvements from the efficiencies of 83–88% without the spray. Although the three cases show similar isothermal performances with spray, the actual efficiencies may differ depending on the pressure. This is because the spray needs higher inlet pressure and consumes more work when the pressure level is higher. On top of the compression efficiency, droplet properties that are critical to determining heat transfer were estimated to observe how the pressure levels affect the properties.
Feasibility of Trapezius Muscle Electromyography and Electrocardiography to Monitor Stress Levels in High Demand Positions
Authors: Ahmed Mohammad H. , Kaya Mehmet , Taebi Amirtaha , Thibbotuwawa Gamage Peshala 
Published: February 2024

Abstract
Prolonged exposure to stress can have detrimental effects on physical and mental health. This study aimed to monitor anxiety levels with minimal sensors by using trapezius muscle EMG and ECG data during a stress task. Ten healthy adults were recruited, and HRV features were compared with EEG to determine alertness during the stress task. EMG data was compared with EEG β and α wave activity to determine stress levels. During the stress task, an increased β to α ratio in EEG indicated heightened alertness and focus, with a significant increase in trapezius muscle activity and asymmetry to indicate increased muscle tension and stress. Trapezius muscle EMG did prove to be an effective method for determining stress when compared to EEG. ECG derived HRV features showed potential to determine stress levels but require further testing. Based on the results, trapezius muscle EMG and ECG can potentially quantify stress and relate anxiety levels from EEG.
Introducing Machine Learning in Undergraduate Mechanical Engineering Mechatronics Classes
Authors: Kim Jinki , Choi Junghun , Kim Jongyeop 
Published: February 2024

Abstract
Machine learning (ML) that has emerged as a new technology for analyzing big data sets to uncover hidden relationships in an increasingly connected world has a great potential to serve as a critical tool for mechanical engineers to develop better devices and to better understand physical phenomena around us. However, compared to the critical importance and impact of ML and increasingly wide adoption of ML in various mechanical engineering fields, very few mechanical engineering undergraduate students receive direct instruction on ML during their undergraduate work. In order to address these concerns, the goal of this research is to improve undergraduate mechanical engineering students’ understanding and use of machine learning. To accomplish this goal, the research team establishes an integrated education framework to effectively introduce ML to junior-level undergraduate ME students through active and authentic learning by providing hands-on activities with mechanical testbeds. The research team incorporated ML into mechatronics lab activities for measuring mechanical vibrations to introduce and practice ML as an alternative method to analyze vibration signals in addition to classical time and frequency domain vibration analysis, which is one of the important subjects in the curriculum of mechanical engineering. The research group first introduced basic concepts of ML and Long Short-Term Memory (LSTM) model which is one of the ML models suitable for predicting one dimensional or time-series data. Students are then tasked to use the vibration signals they measured as input to train an LSTM model that was provided as a pre-filled MATLAB code with blanks for students to adjust. The results of pre- and post-self-assessment survey asked to the students indicate that students have shown great interest in ML, and considered it important for their careers regardless of the pilot ML learning module. On the other hand, after the pilot laboratory, the students’ self-confidence in ML and mechanical vibrations has greatly increased. Furthermore, the interest in mechanical vibrations increased as well, which provided promising opportunities for enhancing students’ learning. This study results enhance our understanding of how exposure to ML affects undergraduate mechanical engineering students’ understanding and attitude toward ML as a non-computing major and their academic achievement in mechanical engineering.
Application of Convex Optimization for Economic Dispatch and DC Optimal Load Flow Problem
Authors: Adapa Rithvik Reddy , Wang Xin 
Published: February 2024

Abstract
The utilization of Economic Dispatch (ED) and DC Optimal Power Flow (DC-OPF) is aimed at minimizing generation costs, while increasing the reliability of power generation. In contrast to traditional loads in power grids that are static, modern smart grid EV charging stations exhibit time-varying dynamic loads. The Electric Vehicle Supply Equipment (EVSE) loads are dependent on the utility price of electricity at the station and the real-time charging in the EVs, which may impact power quality, grid inertia, and power system stability due to their dynamic nature. Therefore, it is crucial to optimize the operation of generators and power systems to ensure the reliable operation of EV-connected smart power grid systems. To address this issue, this paper proposes novel and effective methods for economic dispatch and DC optimal load flow based on convex optimization. The proposed techniques are applied to an IEEE 30-bus system with static loads replaced with EV charging stations at buses 4, 10 and 19 to simulate a typical power system. The total generation cost and total earning from EV charging stations are calculated from the system. The results obtained indicated better values when compared with previous work.
Global Sensitivity Analysis Method for Model-Based System Safety Assessment on Aviation Piston Engine
Authors: Li Guo , Teng Yida , Xu Tongge , Wang Zilu , Ding Shuiting 
Published: February 2024

Abstract
Aviation piston engines provide an important source of power for general aviation, thereby the identification of safety-critical influences during the design phase is an important requirement for ensuring aircraft safety. Model-based system safety assessment have been developed to overcome the limitations of traditional analytical methods in objectively decomposing and identifying failure in complex coupling problems. Nevertheless, the method is limited research for aviation piston engine, especially for determining safety-critical influences from the global perspective of the entire-engine structure with high complexity. In this paper, a new method for rapidly analyzing entire-engine safety sensitivity analysis from the global perspective is proposed, by introducing model-based system safety assessment for the analysis of aviation piston engine. Compared with local sensitivity analysis results, the proposed RSM-Sobol global sensitivity analysis could not only supply additional information on the interactions between parameters but also accommodate rapid iterative complex system safety analysis in the design stage. A methodical case of sensitivity analysis of the structural parameters of a simplified aviation piston engine is given using the proposed method in this paper. Results show that the importance of each parameter can be ranked by the sensitivity index through global sensitivity analysis. Therefore, the safety criteria could be satisfied by reducing the uncertainty of critical parameters and adjusting the input range based on the analysis, allowing an efficient and intuitive safety analysis during design.
An Experimental Study of the Impinging and Freezing Dynamics of Colloidal Droplet on Solid Surfaces
Authors: Abdelmalek Andro , Zhang Xiaoxiao , Liu Yang 
Published: February 2024

Abstract
In this paper, an experimental study was conducted to characterize the dynamics and thermal evolutions of colloidal droplets impinging and freezing on solid surfaces with different wettabilities (i.e., superhydrophobic vs. hydrophilic) towards the development of a novel freezing-based inkjet additive manufacturing (AM) technology. The experiments were carried out in the Freeze Layering Inkjet Printing (FLIP) facility in the Mechanical Engineering Department of the City College of New York (CCNY). While the transient impinging/freezing dynamics of colloidal droplets were resolved by using a high-speed imaging system, the thermal evolutions of the freezing colloidal droplets were also characterized by using a high-speed high-resolution Infrared (IR) thermal imaging system. In addition, the deposition patterns formed under the conventional evaporation-based approach and the novel freezing-sublimation approach were also evaluated by using an automated high-accuracy freeze dryer facility. It was found that the time scale of the dynamic process (i.e., impact, spreading, receding, rebounding, and settling) was much faster than the thermal process (i.e., nucleation and solidification) for both surfaces. The dynamics of the colloidal droplets during the impinging process were coupled with the thermal processes that govern the freezing of the droplets. The surface wettability had a direct effect on both the freezing footprint and the freezing rate.
Life Cycle Assessment of Waste Coal and Biomass Co-Fired Power Plant With Carbon Capture and Storage Technologies
Authors: Sarkar Surja , Bhoi Prakash 
Published: February 2024

Abstract
One of the global concerns that have received a lot of attention recently is climate change. Coal, natural gas, petroleum, and other gases constitute the majority of the fuel used to generate utility-scale electricity in the US. Global warming is a result of widespread emissions of greenhouse gases, particularly CO2, from the combustion of fossil fuels. However, due to their lower carbon footprint, biomass-based heat and power generation are expanding quickly, aiding in the achievement of the target of zero carbon emissions. In this study, the life cycle assessment (LCA) of a 100 MW subcritical waste coal and biomass co-fired power plant with and without carbon capture and storage (CCS) technologies has been assessed considering raw material extraction, transportation, power generation, and associated inputs and outputs. The findings demonstrate that increasing the biomass ratio reduced global warming potential (GWP), and incorporating CCS further decreased the GWP. However, higher biomass ratios and CCS integration led to increased eutrophication, ozone layer depletion, acidification, and other impact potentials.