bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing Innovation and Commercialization of Faculty at a Historically Black College and University
Authors: Peebles Alex , Tyagi Pawan 
Published: January 2025

Abstract
While primarily established as teaching institutions, Historically Black Colleges and Universities (HBCUs) now offer graduate degrees and conduct a significant amount of research. However, HBCUs are behind their non-HBCU counterparts in the process of commercializing their intellectual property, or introducing their innovations to the market where it can be sold to the intended end user. Our goal is to understand the interest and challenges that faculty at HBCUs face in the process of generating and commercializing intellectual property. Here, we present preliminary findings of a survey sent to faculty members in the School of Engineering and Applied Sciences at the University of the District of Columbia. Eleven faculty members responded to the survey, representing the departments of Mechanical Engineering, Civil Engineering, Electrical and Computer Engineering, and Computer Science and Information Technology. Seven (64%) respondents reported that they have developed intellectual property which they believe has commercial potential, however only three respondents (27%) have successfully commercialized their innovations. Respondents reported that the resources available to them for commercialization were either “missing” or “lacking”, and that they had low involvement with industry partners. These results show that HBCU faculty are generating intellectual property but feel stuck commercializing. Investing in the technology transfer offices of HBCUs will spark growth and improve the impact of these important institutions.
Constitutive Modeling of Nonlinear Time-Dependent Mechanical Properties Using Molecular Dynamics Simulations
Authors: Uddin Md Salah 
Published: January 2025

Abstract
Polymeric systems have wide applications in engineering domains such as aerospace, automobile, biomedical, sports goods, packaging, electronics and optics, and energy sectors. These materials exhibit hyperelastic and time-dependent responses such as relaxation and strain-rate-dependent elasticity. Finite element analysis of polymeric components requires material properties for different constitutive models that are obtained from experimental results at the coupon level. Molecular dynamics (MD) simulations can be used to simulate these responses, however, the time and length gap is a challenge to overcome. MD simulations are conducted for a very short time, e.g. nanoseconds to femtoseconds which overestimates the mechanical properties. This study develops a bridging technique for time and predicts stress-stress strain response for cyclic loading at experimental frequency using MD simulations results conducted at high frequency. Molecular models are deformed under cyclic loadings at three different frequencies. Four different strain amplitudes are applied at one frequency. A dimensionless time parameter is introduced and the profile for stress amplitudes transformation to experimental level is predicted. Assuming an underdamped system, the decaying of stress amplitude over time and phase difference is calculated. Experiments are conducted for cyclic loadings of up to three different loads. The prediction agrees well with the experimental results.
A New Methodology for Techno-Economic Comparison of Waste Heat Recovery Options in Industry
Authors: Giordano Lorena , Benedetti Miriam 
Published: January 2025

Abstract
The climate emergency requires a radical transformation of the energy system. Promoting waste heat recovery in industry is crucial to decarbonising its heat consumption, which accounts for more than 50% of the sector’s final energy use. Current literature evaluates waste heat recovery (WHR) projects primarily from an economic perspective, using metrics such as the payback time and the net present value. However, these metrics have inherent limitations, particularly for technologies with high initial costs. There is therefore a need for a more comprehensive assessment that considers their energy, economic and environmental impacts. This study proposes a new methodology to compare industrial WHR options, which provides for the evaluation of a set of energy, economic and environmental performance indices. Notably, this methodology introduces a new index, the Energy Recovery Cost (ERC), which relates benefits such as energy savings and CO2 emissions avoided to the costs incurred over the lifetime of the WHR system. The methodology was applied to six WHR projects identified through the analysis of mandatory energy audits carried out by Italian industrial companies. Firstly, the methodology is validated by comparing the calculated financial indices with the corresponding values from the energy audit reports. Then, the viability of WHR projects is evaluated by comparing the ERCs of WHR projects with the unit cost incurred by the companies to buy or produce the same amount of energy without reusing the waste heat sources. Overall, the ERC provides a new perspective on the evaluation of WHR projects, which can help stakeholders make informed decisions, especially when considering technologies with relatively high initial capital costs.
Computational Fluid Dynamics Analysis of Solar Air Heater Efficiency With Corrugated Absorber Plates in Alkharj, Saudi Arabia
Authors: Alqsair Umar F. 
Published: January 2025

Abstract
In this article, we investigated the performance of a solar air heater. Solar air heaters use solar energy to heat the air in various heating systems. Our study is on August 15 in Al Kharj, Saudi Arabia. For analyzing the performance of the solar air heater, we examined different hours during one day. So, we select different hours from 8 am to 4 pm. The proposed solar heater consists of an absorber plate and a glass cover. The absorber, the most important component in the heating system, has a Corrugated construction with a Chevron design. At different hours, we compare the thermal performance by two different configurations. Once, we considered a flat solar heater, and the other, an inclined solar heater with an angle of 30 degrees. In this study, we performed the numerical simulation using computational fluid dynamics (CFD) via Ansys Fluent software. Therefore, we used the Discrete Ordinates (DO) radiation model to consider radiative heat transfer and the Solar Ray Tracing model to apply solar irradiation. The results confirmed that both in the flat and the inclined absorber cases, the incident radiation has the greatest effect on the thermal performance of the solar air heater.
Topology Optimization of a Landing Gear Part Considering Fatigue Constraint for Additive Manufacturing
Authors: Kim Tae-Uk 
Published: January 2025

Abstract
The combination of topology optimization (TO) and additive manufacturing (AM) is bringing lots of benefits into design and production of aircraft parts. Realizing the complex geometry as near net shape and part simplification by removing fasteners are examples of such advantages, and the related research efforts have been consistently increasing. In this paper, a landing gear torque link is optimized for weight reduction with static and fatigue constraints and fabricated by AM to investigate the possibility of practical use. Many structural designs using TO have considered compliance minimization with constraints such as static strength and volume fraction. But, most aircraft components undergo repeated loadings and it becomes important to consider fatigue life when designing the parts. A landing gear is generally a safe-life structure which does not allow any crack initiation during entire service life, it is essential to identify the damage resulting from fatigue spectrum at the design optimization. The final prototyping results show the possibility of practical usage and applicability to other aircraft parts.
A Two-Step Selective Microscopic Surface Modification Technique: Combining Electrodischarge and Electrochemical Post-Processing
Authors: Ramver Ramver , Tiwari Tanmay , Sekhar Rakurty Chandra 
Published: January 2025

Abstract
This paper introduces an in-situ two-stage surface modification method for micro-sized titanium components, particularly crucial in high-value manufacturing engineering sectors like biomedicine, aerospace, and automotive. The method combines Dry Electric Discharge Surface Modification (Dry-EDSM) for selective nitriding and Electrochemical Polishing (ECPP) to refine surface quality. Detailed characterization including X-ray diffraction, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), white light interferometry (WLI), and micro-hardness, confirms the effectiveness of the combined approach in achieving desired modifications while also highlighting the impact of process parameters on surface properties. Surface characterization following Dry-EDSM revealed a titanium nitride layer, hard but initially rough. Post-processing notably increased micro-hardness by 35% (from 300 HV to 405 HV) and reduced surface roughness by 84% (from 4.5 μm to 0.72 μm). The average surface modification layer thickness decreased from 33 μm pre-ECPP to approximately 21.3 μm post-ECPP. XRD analysis confirmed titanium nitride presence post-ECPP. ECPP eliminated rough ridges and valley-like features, rendering the surface smoother and crack-free, affirming the combined approach’s efficacy in achieving desired modifications while preserving micro-sized component integrity. The findings of this study significantly advance surface modification techniques by developing a cost-effective in-situ machining and post-processing approach for micro-components, offering valuable insights for industries reliant on precise surface characteristics.
Simulation Based Analysis and Design of Passive Back Exoskeleton for Squat Lifting
Authors: Sahu Neha , Gupta Abhishek 
Published: January 2025

Abstract
Back pain is the most common musculoskeletal disorder that manual material handling laborers face as they lift heavy objects. To overcome the back pain problem, it is advised to wear assistance (Exoskeleton) during lifting. Through musculoskeletal simulation, this work investigates how the passive back exoskeleton affects the spinal muscle forces and spinal joint reaction loads. Such simulation findings can provide insights to improve the back exoskeleton design further. For this purpose, the passive exoskeleton is modeled as a set of elastic elements (springs), and dynamic analysis for a lifting cycle is done during a squat lifting task. Musculoskeletal simulations were carried out in OpenSim software utilizing the open-source OpenSim lifting full body (LFB) model. The LFB model is modified by adding an external spring that provides assistive forces like a passive exoskeleton. During the whole lifting cycle, the erector spine muscle is strained, so unloading the erector spinea muscle is the primary goal of most back support exoskeletons. This work aims to identify optimal spring configurations for the design of a passive back exoskeleton to aid in squat lifting. Corresponding spring stiffnesses will also be determined. The optimized back exoskeleton is expected to reduce compressive and shear forces on the L5S1 joint during lifting.
Use of Game Theory for Strategic Scheduling of Different Types of Chillers
Authors: Allen-Magande Hugh , Khazaii Javad , Esmaeili Amin , Khazaei Ali 
Published: January 2025

Abstract
Abstracts Game theory is a decision-making tool that focuses on the strategic planning for cooperative or non-cooperative (conflicting) problems by two or more agents. All agents’ decisions directly affect the outcomes (pay-offs) received by each of them. Strategic operation of the equipment in the mechanical room of any commercial building can have a significant energy-saving impact. Chillers and boilers are the two primary energy-consuming equipment in cooling and heating systems. Regular centrifugal chillers consume energy when electricity is used to run the refrigeration cycle inside the chiller (mainly consumed to operate compressors). At the same time, hot water boilers consume natural gas to heat the building’s air conditioning and water. It is important to remind here that in large commercial buildings, throughout the year, both chillers and boilers are required to operate at the same time — for the building cooling, heating, reheating, and water heating needs — and not just chillers for hot seasons and heating for cold seasons. Absorption chillers are a different type of chiller that, instead of consuming electricity at compressors, uses heat for the compression process of the cooling generation cycle. A pump in this system consumes a much lower quantity of electricity relative to the compressor in vapor-compression cycles. The aforementioned will result in a considerably larger consumption of natural gas and a significantly lower consumption of electricity instead. It is also customary for designers to have at least two chillers (each at capacity higher than 50% capacity of the whole system) for each building to keep at least a level of backup capacity when one of the chillers is out of commission due to required service or due to unexpected system failure.
In the current paper, the authors will use the rules of game theory to make the most energy-efficient scheduling decisions for energy saving in a typical air conditioning system when utilizing two different types of chillers in one building. The authors will compare the overall energy consumption of a typical system using two centrifugal chillers, two absorption chillers, or one of each, and recommend the most efficient strategy for the building.
High Strain Rate Fracture of Shear Wrinkled Graphene
Authors: Avasarala Nandana , Kim Leo , Dorsey Fahim , Park Jungkyu 
Published: January 2025

Abstract
This study explores the mechanical responses of shear-wrinkled graphene to high strain rate impacts, employing molecular dynamics simulations to model the high-speed fracturing of this material. Initially, we induce shear in a graphene layer to naturally create wrinkles, following which a silver particle is propelled at the wrinkled graphene at predetermined velocities. The interaction between silver and carbon atoms is modeled using the Lennard-Jones potential, while silver atoms themselves are simulated via the embedded atom method (EAM) potential, with the second-generation REBO potential governing the carbon atoms with a cutoff distance of 2.0 Ångström. Our results reveal that shear-wrinkled graphene demonstrates greater stiffness compared to its unwrinkled counterpart, absorbing less impact energy. Notably, all graphene layers, regardless of wrinkling or shear deformation, fracture upon impact at velocities of 5 km/s, suggesting that fracture is primarily influenced by C-C bond breakage rather than pre-existing deformations. This investigation marks a significant step towards the development of robust, lightweight materials designed for military applications, significantly enriching the defense technology sector.
Identification and Localization of Areas of Damage in Composite Materials Using Infrared Thermography and Artificial Intelligence
Authors: Barua Aditi , Dabetwar Shweta 
Published: January 2025

Abstract
This study investigates the integration of Mask RCNN with Infrared (IR) thermography for non-destructive testing to detect defects in composite materials. Due to their high strength-to-weight ratio and customizable properties, composite materials are widely used in various engineering applications. However, these materials are prone to subsurface defects such as delamination, cracks, and voids which cannot be detected by visual inspection. Traditional defect detection methods are limited, emphasizing the need for advanced techniques like IR thermography, which detects surface heat variances indicative of underlying defects. The research introduces a high-fidelity instance segmentation model, namely, Mask RCNN that is capable of identifying the defects in thermal images. The model is analyzed for sensitivity with respect to the number of epochs. The results showed accurate identification and localization of multiple types of subsurface defects. Sensitivity analysis showed that the accuracy improved from about 77% at epoch 30 to 97% at epoch 120, while the training loss decreased from 0.13 to 0.07. These results highlight the model’s learning efficiency and potential for real-time monitoring of structural integrity. This approach not only advances non-destructive testing technologies but also provides a scalable option for ongoing structural health monitoring of composite materials, ensuring their safety and functionality in engineering applications.
Measurement of Chaotic Complexity in a Planar Mechanism Due to the Motion of the Follower With Clearance Using Lyapunov Exponent, Phase Plane Diagram, Poincaré Map, and Spectral Entropy Representations
Authors: Yousuf Louay S. 
Published: January 2025

Abstract
This paper considers the planar mechanism with rotating cam, flat faced follower, two guides with clearance, crank arm and connecting rod. There is clearance between the follower stem and guide by taking into consideration the effect of impact and friction. The aim of this paper is to describe the complex dynamic motion of the mentioned planar mechanism using different chaotic methods at different cam speeds and different follower guide’s clearance under normal impact and impact with coefficient of restitution. Time delay and global embedding dimension are used using the algorithm of mutual average information and false nearest neighbors algorithms. Lyapunov exponent is extracted at different cam speeds and different follower guide’s clearance. Spectral entropy is used to detect the chaos due to the white noise at different contact levels and high speeds of the cam. SolidWorks program is used to calculate the point linear displacement at the contact point between the cam and the follower. The dynamic tool package algorithm has been written using Matlab software to describe the chaotic motion. Moreover, phase plane diagram, and Poincaré map are added to the detection of the dynamic chaotic motion. The normal impact and impact with coefficient of restitution have been taken into account in this paper. Time delay and global embedding dimensions are contributed in the calculation of Lyapunov exponent. Regarding largest Lyapunov exponent, the system with follower guide 17 mm and 19 mm at cam speeds 2000 rpm and 1200 rpm have a chaotic motion since the numeric values of Lyapunov exponent is positive. Regarding the Poincaré diagram, the system with the cam speed 100 rpm and coefficient of restitution 0.2 has a quasi-periodic motion while the other systems have chaotic motion. Regarding the phase diagram, the cross linking of point linear displacement is increased with the increment of cam speeds, coefficient of restitution, and follower guide clearance.
Failure Analysis for Lock Sensing Limit Switch on EMU Door System
Authors: Wu Lvxian , Hong Haifeng , Zhang Xiaoming , Zhang Long , Lu Hang , Li Dong , Yin Yanbo , Tang Yuxuan , Huang Wei , Chen Qiubo 
Published: January 2025

Abstract
The EMU plug sliding door system’s security loop relies on two crucial components: the lock limit switch and the lock sensing limit switch, wired in series. Any malfunction in either switch during operation can disrupt the train’s ability to initiate traction during berthing or induce emergency brake during revenue service, leading to operational issues, and impacting the service schedule and service life of the vehicle. Thus, ensuring the high-quality manufacture and precise installation of these limit switches is paramount. This paper focuses on the analysis of serval fault reports of the security loop. Upon inspection of current units, sporadic lock sensing limit switch malfunctions emerge as the primary cause of safety loop failures. Consequently, this paper aims to conduct an in-depth analysis of lock sensing limit switch failures on different train series, focusing on identifying the underlying issues and proposing practical solutions. Investigations and testing were conducted on actuation force, fitness of the components, and electrochemical oxidation to identify the root cause of the safety loop’s failure. A manufacturing defect was located and corrected significantly reducing the failure rate. Further correction, experience, and suggestions are provided for manufacturers and car builders.
Sensor Optimization for Damage Detection Within a Digital Twin Framework
Authors: He Junyan , Aguilar Enixe , Eger Markus , Sotoudeh Zahra , Zhuang Linqi 
Published: January 2025

Abstract
A random forest model is trained on dataset generated by finite element (FE) simulation to predict the damage location on a metallic plate. An optimization framework is integrated to identify minimal number of sensors required and optimal sensor placements. The accuracy of the FE model was validated against analytical solutions and experimental measurements, where satisfactory agreement was found with analytical solutions. The out-of-plane displacement and the normal strain at the bottom of the plate surface were extracted from the simulation at different virtual sensor locations to serve as inputs to the random forest model. It was found that satisfactory prediction accuracy can be achieved with just two sensors for this specific problem. Using a response surface optimization method, the optimal sensor locations that minimizes prediction error are identified, and achieved higher accuracy than the baseline case with equidistant sensor placement. This study lays a strong foundation for developing a machine-learning-based structural health monitoring model within a digital twin framework.
A Non-Destructive Testing Method for Rolling Bearing Internal Temperature Based on Ultrasonic Signals
Authors: Zhang Rongfeng , Chen Li , Zhou Rui , Liu Heng , Qi Shemiao , Liu Yi , Li Yuan 
Published: January 2025

Abstract
Obtaining the internal temperature of rolling element bearings during the operation plays a vital role in the dynamic analysis of the bearings. A non-destructive testing method of the internal temperature of the outer race based on the ultrasonic signals is proposed in this paper. The study initially measured the speed of sound at various temperatures using the same bearing steel as the tested bearing outer race. The measurement results revealed a significant linear correlation between the speed of sound and material temperature, which also provided the reliability of the proposed method. The operating temperature of the outer race of an N306 cylindrical roller bearing was tested in this paper. In addition to measuring the internal temperature, a temperature sensor was used to obtain the surface temperature. When properly lubricated, the lubricant removes most of the heat inside the bearing. This results in the surface temperature being slightly lower than the tested internal temperature. As the bearing is inadequately lubricated, more heat is transferred to the outer race surface, leading to a larger temperature difference. The test results indicate that monitoring the internal and surface temperature of the outer race can detect changes in the bearing’s operating condition.