bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on Tone Quality for Vehicles Considering the Masking Effect
Authors: Lin Jiewei , Zhang Rui , Zhou Qidi , Zhang Junhong , Lin Gengyi 
Published: January 2022

Abstract
Sound quality (SQ) plays important role in automobile competitiveness, in which the high frequency characteristics of tones are prominent when internal combustion engines are replaced by fuel cells or batteries. Hence, it is of great significance to explore the influence of tones on the SQ of such electric vehicles. At the moment, the prominence of tones is concerned but the influence of tones in different frequency ranges is not comprehensively considered. Meanwhile, there are some researches on the masking effect of background noise, but they are insufficient. To address these issues, the SQs of four types of vehicles (van, SUV, pure electric car, fuel cell heavy truck) are studied. The prominence ratio (PR) is found to be effective in the evaluation of tones SQ. The influence of tones on subjective evaluation is explored from two dimensions of “audible” and “irritable”. The results show that whether tones can be “audible” and “irritable” are related to the masking effect of background noise and the frequency distribution. Meanwhile, the PR limits of tones are obtained in different frequencies under various working conditions and operating modes.
Mass Transport and Thermal Stresses Evaluation of Micro Solid-Oxide Fuel Cells: A Numerical Study
Authors: Osman Sameer , Ahmed Mahmoud 
Published: January 2022

Abstract
Solid-oxide fuel cell (SOFC) are among the highest types of fuel cells in terms of efficiency, reaching as high as 65%. However, poor mechanical robustness and thermal cycling stability are the major disadvantages of these fuel cells due to high thermal stresses between layers. A new concept of a micro-monolithic ceramic cell was previously introduced that had extremely high power-densities (&gt; 10 W/cm3) as well as high mechanical robustness and thermal cycling stability. In this study, a 3D comprehensive theoretical model is presented for ceramic fuel cells, which includes species, charge, momentum, and energy transport. Moreover, the bilinear elastoplastic material model is used to estimate thermal stresses in ceramics at high temperatures. This model is then used to simulate two new geometries for the cell and anode flow channels. Results indicate that circular anode channels are best in terms of thermal stresses, while being inferior in terms of electrochemical performance. A hexagonal cell with trapezoidal flow channels yielded the highest volumetric power density with an increase of 15% compared to the plain circular arrangement. On the other hand, circular sector flow channel increased the power density by only 9%. The increased current of the cell with the circular sectors and trapezoidal sections is due to the more efficient distribution of flow channel area such that the travel path for hydrogen gas is less restricted in terms of diffusion. As for the thermal stress, the newly introduced configurations increased the values of stress by 64% for the circular sector channels, compared to only 16% for the trapezoidal flow channels. This study is meant as an initial step in the optimization process for the microtubular SOFC with high volumetric power density, creating an opportunity for performance enhancement of this type of fuel cell.
An Imperfect Usage-Based Preventive Maintenance Planning Model for Railway Track Superstructures
Authors: Dinmohammadi Fateme , Shafiee Mahmood , Zio Enrico 
Published: January 2022

Abstract
Railway transport is considered one of the most reliable, comfortable and safest modes of travel for both freight and passengers. Rail infrastructure assets (such as tracks, bridges, earthworks, tunnels and drainage systems) must be inspected and maintained on a regular basis in order to ensure that transport services are delivered in compliance with contractual and legal obligations. The maintenance of railway track structures is preventive in nature and includes the repair or replacement of certain components at pre-determined time intervals (in terms of years of operation) and/or usage rates (in terms of gross tonnage). Maintenance actions such as grinding and stone-blowing either restore the track profile to its original condition, i.e., “as good as new (AGAN)”, leave the track in almost the same condition as it was in prior to the inspection, i.e., “as bad as old (ABAO)”, or restore the track condition to a state somewhere between AGAN and ABAO, i.e., the so-called imperfect maintenance. The effect of an imperfect maintenance is often characterized by two classes of models, namely, failure-intensity reduction and age-reduction. However, the impact of imperfect repair on assets’ usage has not yet been addressed in the literature. In this paper, a usage-based imperfect preventive maintenance (PM) planning model is proposed for railway track superstructures, where the effect of an imperfect maintenance is described by a reduced amount of total accumulated million gross tons (MGT) passed over the rail line. A constrained nonlinear programming model is formulated to optimize the maintenance interval (i.e., usage rate between consecutive PMs) and the degree (quality) of repair actions. The total mean maintenance cost for a Weibull failure distribution model is derived and, then, the conditions required to make PM actions beneficial are discussed. A numerical case example is provided to show the effectiveness of the proposed PM planning method over the track renewal and replacement policy.
Performance Assessment of a Closed Greenhouse in a Hot Arid Australian Climate
Authors: Hegazy Anwar , Subiantoro Alison , Norris Stuart 
Published: January 2022

Abstract
In this paper, we present a validated thermal model of a greenhouse. Then summer climatic data of a location in South of Australia (Port Augusta), known to have dry and hot summer, is used to compare the potential of different cooling technologies in providing cooling to greenhouse indoor air while considering the minimization of water consumption. Several cases are examined and compared to a reference case which is a closed greenhouse without cooling. The operation cases considered for cooling purpose are 1 - Fogging system; 2 - Single pipe Earth-to-Air Heat Exchanger (EAHE); 3 - Multiple pipe EAHE; 4 - combined operation of Fogging system and EAHE. Results indicated that relying on shallow geothermal energy through an Earth-to-Air Heat Exchanger (EAHE) minimized the water consumption of the fogging system reducing it from 11.6 to 4.7 kg/day. Furthermore, the results show that cooling via EAHE is the best strategy in terms of reducing water consumption without significantly affecting the temperature reduction when compared to the water reliant cooling technology fogging system. The combined operation of EAHE and fogging system managed to keep the indoor air condition at the favorable plant cultivation temperature level (20–30°C) and relative humidity (70–80%).
Direct Measurement of Thermal Boundary Resistance Reduction Due to Electron Carriers by Photothermal Radiometery
Authors: Villarreal Ezekiel , Horny Nicolas , Ban Heng 
Published: January 2022

Abstract
A thermal boundary resistance occurs between any two surfaces that are not in perfect contact with each other. It is well predicted that this thermal resistance decreases as heat carriers, typically phonons or electrons, cross the contact surface. While phonon transport and electron transport are well documented in a number of conditions, direct measurement of the electron contribution to thermal boundary resistance across micro layers has not been shown. Understanding the effect of electrons on the heat transfer of thin layer is very important in understanding the thermal behavior of micro- and nano-electronics, which has impact on both the life and the reliability of electronics. This paper presents an experimental test on the heat transfer as electrons cross the boundary of an n-doped Schottky Diode. Photothermal Radiometry (PTR) measurements were then taken to determine the thermal boundary resistance. Measurements were made on the same diode in both the open and closed state. The obtained open and closed fit parameters were then compared with each other to determine the reduction in thermal boundary resistance. It was found that the thermal boundary resistance of the diode in its opened state was 8.4 K m /GW; while the thermal boundary resistance was 6.4 K m /GW when the Schottky diode was closed with current of 100 mA. This represents a reduction in the thermal boundary resistance of approximately 24% for the case where the electrons were crossing the boundary. This result confirms experimentally that the electron heat transport effectively reduces the thermal resistance across boundaries.
Thermal Performance of a Packed Bed Latent Heat Thermal Energy Storage With Pure Silicon as PCM
Authors: Saha Sumit , Md. Ruslan Abu Raj , Morshed A. K. M. M. , Paul Titan C. 
Published: January 2022

Abstract
In this paper, effect of mass flow rate and inlet temperature on the thermal performance of a packed bed latent heat thermal energy storage has been numerically investigated. As the Heat Transfer Fluid (HTF), hot air is selected. Pure silicon is chosen as the PCM (Phase Change Material). The thermal performance has been evaluated on the basis of the following parameters: total heat transferred (Qcharging), TES charging rate (p), TES density (q), TES rate density (w). The values of these parameters have been calculated and compared for four different mass flow rates (0.08 Kg/s, 0.1 Kg/s, 0.12 Kg/s, 0.15 Kg/s) and four different inlet temperatures (1800 K, 1900 K, 2000 K, 2100 K) of the HTF for a charging period of 500 s. The simulations reveal a 0.54% increase per 1% increase in HTF mass flow rate and 15.6% increase per 1% increase in HTF inlet temperature in values of all the parameters after the charging period. A conclusion can be drawn that the HTF inlet temperature has more impact on the performance of packed bed latent heat thermal energy storage than HTF mass flow rate.
Thermal Circuit Analysis of Droplet Evaporation on Hot Microstructured Superhydrophobic Surfaces
Authors: Huang Wenge , He Xukun , Cheng Jiangtao 
Published: January 2022

Abstract
In this paper, the evaporation dynamics of solitary water droplet dwelling on the hot micro-structured superhydrophobic surfaces is experimentally and theoretically investigated. For the first time, two distinguished components of heat and mass transfer, i.e., from the droplet cap and the base surface, during the droplet evaporation are systematically studied. Considering all the thermal resistances from the heated substrate to the droplet cap surface, a comprehensive thermal circuit model is developed to analyze the effects of micropillars and substrate temperature on the sessile droplet evaporation. As substrate temperature increases, a more apparent temperature mismatch between droplet cap surface and heated substrate is experimentally observed, which could be explained by the increasing droplet cap surface evaporation rate and its evaporative cooling effect. Moreover, the increasing temperature of droplet cap during the evaporation could be successfully predicted by our model, indicating the component of evaporation ratio from the droplet base surface (φ) decreases. This work could advance our understanding of droplet evaporation on heated superhydrophobic surfaces and further provide us a new tool to accurately predict droplet temperature and evaporation rate during the evaporation process.
Cutting Fluid Application for Bandsawing: A Sustainable Solution for Cutting Solids
Authors: Rakurty C. S. , Rangasamy Nithin 
Published: January 2022

Abstract
The band saw cutting is one of the many cutting/machining operations that can benefit from cutting conditions and cutting fluid optimization. Optimizing cutting speed, feed rate, and cutting fluid application based on the cut material can increase the blade’s life. Most of the academic and industry work focuses on optimizing the cutting tool design and cutting conditions such as band saw blade speed and feed rate. Most of the band sawing industry uses flood cutting fluid to reduce the cutting temperatures, remove chips, and (in some cases) act as a lubricant. There is a lack of comprehensive understanding of the role of cutting fluid, and its method of application in the band saw cutting. In this paper, cutting fluid application on the cutting performance metrics such as surface roughness, (feed) force, and cutting edge wear (at ten cuts) were studied. The study also focuses on the chip formation and cutting temperatures generated while cutting with and without cutting fluid application. A flood cutting fluid application (recommended for the D2 tool steel), varying amounts, and compositions of the minimum quantity cutting fluid applications were studied along with dry (or no cutting fluid application) cutting. D2 tool steel material was used as workpiece material, and a carbide-tipped band saw blade was used as the cutting tool. In general, the band saw teeth split the kerf to improve the cutting process through reduced cutting temperatures and forces. The cutting conditions influence the chip formation and kerf splitting process. The results show that the minimum quantity cutting fluid applications negatively influenced the cutting performance. They produced the highest feed forces and caused severe tooth damage compared to the other experimental conditions. The results concluded that dry (no cutting fluid application) is recommended for cutting D2 tool steel material. This road map can be used to improve the band saw blade life and improve the cut-surface roughness.
Demand Response Analysis for Different Residential Personas in a Comfort-Driven Behavioral Context
Authors: Olawale Opeoluwa Wonuola , Gilbert Benjamin , Reyna Janet 
Published: January 2022

Abstract
Low demand response (DR) participation and high program drop-out rates continue to impede DR goals that could save up to $13 billion in annual grid expansion and electricity demand costs. Yet, the literature lacks a thorough understanding of how different residential customer segments enrolled in DR programs respond to utility signals in view of occupant comfort considerations. The objective of this study is to gain a clear understanding of the effects of four different customer personas on residential DR. Given current data limitations, this work developed an array of hypothetical personas with varied priorities, activity levels, and comfort thresholds based on demographic variables that have been found in previous studies to influence energy consumption. A BEopt™ DR model for a reference residential single-family building located in Colorado was built to isolate the effect of differences in buildings or climate. The results provide useful evidence on how persona-comfort differences lead to significant deviations in DR goals (especially peak demand reduction), ranging from 0.1% to 20%. This work presents a novel framework representing comfort preferences in DR models. The data generated, albeit synthetic, and the results could inform DR program design considerations of how different people respond to different comfort priorities.
Irradiation and Thermal Post-Processing for Vat-Polymerization Additive Manufacturing: Tensile Properties of Four Formlabs Resins
Authors: Baumgarner Julia , Piovesan Davide 
Published: January 2022

Abstract
With the introduction and recent advances of additive manufacturing there are a number of materials available for creating medical prototypes. Of particular interest are materials used for imitating bone properties for the execution of mock preparatory surgeries. However, when designing a print for a model it is important to understand the mechanical properties of each material. One of the most common methods of 3d printing is stereolithography. In this paper, four Formlabs resins were tested in tensile loading. Clear, Durable, Tough, and High Temperature resins were used for testing. Samples were tested with and without post-processing curing. Curing was performed in a customized curing oven that follows the Formlabs requirements. After testing, mechanical properties were calculated for all sample groups.
Ultrasound Assisted Production of Metal Foam From Polyurethane Precursor
Authors: Zahoor Asima , Mourad Abdel-Hamid I. 
Published: January 2022

Abstract
Metal foam is a novel class of metals that is inspired by naturally occurring, functionally graded, cellular structures like wood and bones. The properties of metal foam are so diverse that they can be tailored to suit the particular need, hence the study of metal foams has become attractive to researchers and efforts are being made to optimize the methodology to develop the metal foam. Most of the production methods cannot be widely utilized because of difficult process control and high production costs. One of the most economical ways to produce metal foam is adopting conventional electro deposition technique. The electro deposition technique starts from first metalizing the non-conducting polymeric foam and then electrically depositing metal onto this metallized precursor foam with open cells and later the precursor is removed by the sintering process. The main hindrance in this process is that foam being multi layered, a uniform deposition of the metal in the inner layers of the foam was not achieved. After sintering it was found that the foam sample turned out hollow at the center, due to lack or very less deposition of the metal. Experiments aiming to overcome this problem of non-uniform deposition of the metal in the inner layers of the precursor were conducted. It was found that mechanical agitation in the form of low frequency ultrasound promoted the uniform electro deposition throughout the metalized multilayered precursor. Finally, desired strength foam was produced.
Parametric Optimization of SMA Torsional Actuators for Aircraft Morphing Applications
Authors: Summers Christopher , Weaver-Rosen Jonathan M. , Karakalas Anargyros A. , Malak Richard J. , Lagoudas Dimitris C. 
Published: January 2022

Abstract
Novel design of more efficient, environmentally friendly, quiet, and cost-effective air transportation could be substantially benefited by introducing highly adaptive, multi-functional systems that are able to mimic the operation of biological systems, like birds. Altering the Outer Mold Line (OML) of an aircraft allows for achieving the optimal response under a wide range of operational conditions. In the framework of the “Adaptive Aerostructures for Revolutionary Civil Supersonic Transportation” project funded by NASA, an articulated panel mechanism controlled by Shape Memory Alloy (SMA) actuators is investigated as a means for reducing the perceived loudness of the sonic boom produced by a commercial aircraft when flying at supersonic speeds. A pair of SMA torque tubes is envisioned to induce the required rotation of the panels in order to achieve the desirable OML shapes. However, design objectives such as minimizing power consumption, mass, and cooling time are often competing and the selection of the optimal dimensions is neither elementary nor straightforward. In the research conducted herein, a case study is defined and realized for the optimal design of the SMA torque tubes as part of a larger morphing structure. In the early stages of design, engineers are often faced with the challenge of making decisions with incomplete information. For example, the designer must know the aerodynamic loads to choose the optimal dimensions, but the aerodynamic loads depend on aircraft dimensions. To enable detailed optimization in the early design stages, parametric optimization can be used to solve for the parameterized Pareto frontier. This parameterized Pareto frontier allows a designer to explore how the traditional Pareto frontier might change as exogenous parameters (the values of which are not yet fully known) change. In this work, the design variables under the control of the engineer are the dimensions of the torque tube, i.e. length, inner diameter, and thickness. The objectives are to minimize cooling time and maximize rigidity. The exogenous parameters outside of the designer’s control include the required actuation stroke and aerodynamic forces. Results show the effects of parameters on the objective tradeoffs and demonstrate how an engineer can choose an optimal solution once the parameter values are known.
Design of a Personalized Bio-Mechanical Knee Orthosis
Authors: Tacescu Alex , Goldfarb Nathaniel , Secino Benjamin , Fischer Gregory S. 
Published: January 2022

Abstract
Exoskeleton joints should be aligned and follow the anatomy of the person to prevent putting additional strain on the ligaments or creating skin complications through rubbing between the patient and the exoskeleton. The human knee is a challenging joint to replicate accurately since its motion is not a simple hinge joint; the knee rotates through its range of motion while the tibia extends relative to the joint center. This paper presents a powered biomechanical-inspired knee joint for an exoskeleton developed to follow the flexion-extension motion. By utilizing previous literature that used Magnetic Resonance Imaging scans to identify the relationship of flexion-extension, the design requirements for the knee mechanism were defined. The flexion-extension motion was used to determine the polynomial-shaped cam mechanism, translating the shank segment as the joint rotates. This knee joint takes advantage of Fused Deposition Modeling 3D printing, allowing the knee to be easily manufactured and customized. Motion capture and finite element analysis are used to validate the motion and mechanical strength. The final biomechanical knee joint is highly customizable and easy to manufacture.
Gait Stability Using Lyapunov Exponents
Authors: Galarza Jose , Caruntu Dumitru I. , Vasquez Simon , Freeman Robert 
Published: January 2022

Abstract
This work deals with the stability of the dynamics of human gait. This is a common exercise. The focus of this investigation is to analyze the knee angle time series and calculate the divergence for over-ground and treadmill walking. Experiments using motion capture technology are used to capture the movement. MATLAB software package is used to calculate the Lyapunov Exponents from the time series. Results are compared with similar studies in the literature. This work provides an insight on the level of stability for treadmill walking. A comparison with stability of normal gait might give an insight on how the treadmill can facilitate rehabilitation using gait.