bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and Development of Flexible Systems Load Deflection Tester
Authors: Tekes Ayse , Mayeed Mohammed , McFall Kevin 
Published: January 2020

Abstract
This study presents the design and development of a novel, low-cost load-deflection test setup providing the testing of flexible links and compliant mechanisms. Test bench consists of two stepper motors, lead screw, rail system, two carts, two clamps, bearings and a force sensor. Clamps are designed in a way to attach various types of compliant members such as pinned-pinned buckling beam, fixed-fixed beam and 3D printed links. Mechanism enables to calculate the stiffness of compliant and 3D printed flexible systems. Sliders are displaced quasi-statically to slowly stretch or compress the flexible members attached in between two clamps. Displacement of the carts and deflection of the midpoint of the buckling beams are captured using machine vision measurement. Force applied from one of the carts to the end of the attached link is recorded using the force sensor. Stiffness of 3D printed flexible translational vibratory mechanisms is obtained using the displacement of the carts and load deflection curve of buckling beams are obtained using deflection curve and load data. Experimental results are compared with the same simulations performed by FEA analysis.
Decentralized Multi-Robot Motion Planning Applicable to Dynamic Environment
Authors: Wu Bin , Suh C. Steve 
Published: January 2020

Abstract
Multi-robots navigation in dynamic environment is a promising topic in intelligent robotics with motion planning being one of the fundamental problems. However, in practicel, multi-robots motion planning is challenging with traditional centralized approach since computational demand makes it less practical and robust for the motion planning of a large number of robots. In this paper, a decentralized distribute robots motion planning framework (DDRMPF) is discussed which addresses the specific issue. DDRMPF directly maps raw sensor data to steering command to generate optimal paths for each constituent robot. Unlike centralized method which needs a complete observation along with a center agent which processes heavy data collected from all the robots, DDRMPF allows each agent to generate an optimal local path needing only partial observation, thus rendering motion planning involving large numbers of robots more practical and robust. DDRMPF trains the policy for each robot in the complex and dynamic environment simultaneously based on the reinforcement algorithm.
Analysis of Ablation Volume Produced During Microwave Ablation of Breast Cancerous Lesion Using Fourier and Non-Fourier Models
Authors: Satish Vellavalapalli , Kumar Jatin , Repaka Ramjee 
Published: January 2020

Abstract
The present article aims to compare the change in the temperature and ablation volume during Microwave ablation procedure. The microwave ablation process is carried out using Fourier and non-Fourier bioheat transfer models in the computational domain of breast tumor. The above models have been considered with the relaxation time known as thermal delay during ablation procedure at constant power and frequency. The above objective has been carried out on a heterogeneous three compartment Breast model using COMSOL-Multiphysics software, with inbuilt bioheat transfer and electromagnetic waves Physics interfaces. The simulation results show that the ablation volume is slightly greater while using Fourier bioheat transfer model as compared to the non-Fourier bioheat transfer model. Further, the temperature distribution also shows that there is a slight variation initially at the start of the ablation, i.e., Fourier heat transfer model shows nearly 2°C more temperature as compared to the non Fourier model and becomes equal as the time increases. The present study helps in establishing the better clinical procedure of Microwave Ablation technique.
Effect of the Die Hole Structure and Distribution on the Strength of Ring Die in Pelletizing Equipment
Authors: Li Junhong , Sun Yu , Wu Kai , Wang Yu 
Published: January 2020

Abstract
The short life and high cost of ring die restrict the development of pelletizing technology severely. To solve the problem, this paper focuses on the effect of die hole structure and distribution on the die strength by finite element analysis. At first, a parametric model with one random hole surrounded by six same holes is established. Through ANSYS Design Exploration, the significant design parameters affecting the deformation and stress of the die were clarified. Furthermore, the effects of the significant parameters on the total deformation and equivalent stress were obtained by response surface analysis. In addition, the empirical equations between deformation/stress and the significant parameters were developed and the interactions of any two parameters were investigated. The results show that the equations reach a high degree of significance and the coefficient of determination R2 is 0.9803, which means it can predict the total deformation and equivalent stress correctly. Moreover, the optimal combination of the parameters was achieved. When the smallest deformation and equivalent stress of ring die are obtained in the range of parameters value, the cone angle of die hole inlet is 14.67°, the effective diameter is 2.7mm, the radial vertical distance between two adjacent die holes is 10mm and the angle is 2.7°. Using the multi-objective optimization method based on the finite element to study the influence of design parameters on the ring die strength provides an effective method and idea for the design of ring die.
Equilibrium Equations of Incremental Forces and its Application in Assembly Variation Analysis of Compliant Structures
Authors: Niu Zhihua , Li Zhimin , Jin Sun , Li Xinxin 
Published: January 2020

Abstract
Assembly variation analysis is used to handle the tradeoff between product performance and manufacturing cost. Traditionally, the assembly variation analysis of compliant structures is achieved by combining finite element analysis (FEA) and Monte Carlo simulation. Although the distribution of assembly dimensions can be obtained by such a process, the internal relationships between component deviations and assembly precisions are hidden in the reduplicative computational process. This study aims to shed light on the internal relationships between component deviations and assembly deformations of compliant mechanisms by Equilibrium Equations of Incremental Forces (EEIF). Dimensional deviation is an additional part to theoretical dimension, so does incremental force is to theoretical assembly load. EEIF is the bridge between dimensional deviations and incremental forces. This paper extends the application area of EEIF from compliant joints to compliant beams. The beginning of this paper reviews mainstream assembly variation analysis methods and the application of compliant mechanisms. Following is the basic conceptions about Equilibrium Equations of Incremental Forces. In the theory development part, compliant joints and compliant beams are discussed respectively. Precision of the method is verified by comparing it with an ADAMS/Flex model. Then, the output sensitivity coefficient matrix is used to conduct statistical assembly variation analysis for compliant mechanisms.
Micro-Hydrokinetic Turbine Operating in the Vicinity of a Free Surface: Multiphase Large Eddy Simulations
Authors: Attiya Bashar , Altimemy Muhannad , Daskiran Cosan , Liu I-Han , Oztekin Alparslan 
Published: January 2020

Abstract
Large Eddy Simulation (LES) turbulence and multiphase Volume of Fluid (VOF) model are employed to predict the spatial and temporal characteristics of the turbulent flow structures near micro-hydrokinetic turbine operating in the proximity of a free surface. The turbine power performance and the free surface dynamics, and its interaction with the turbine are characterized by examining the results of both single-phase and multiphase flow simulations. Simulations are conducted at the turbine’s best efficiency point at a tip speed ratio of 1.86 with the rotation rate of 150 rpm and the free stream water velocity of 2.25 m/s. The multiphase flow simulation is carried out at Froude number of 1.06. The results indicate slight interaction between the deformed free surface and the turbine wake structures. Acceleration in the flow velocity is observed near the free surface due to the physical confinement. The results indicate that turbine power generation is reduced by about 2.0%, and the thrust coefficient is reduced by 1.60%. It is demonstrated that the turbine performance at this Froude number is hardly influenced by the presence of the free surface.
Surgical Bone Drilling: A Review
Authors: Samarasinghe Chandana , Uddin Mohammad , Bari Saiful , Xian Cory 
Published: January 2020

Abstract
Bone drilling is an important step in orthopedic surgeries for the reconstruction and repair of fractured bones. The main concern in bone drilling is to create holes without causing minimum damage to the bone tissues. It is well reported that high temperature and high force in drilling cause bone thermal necrosis leading to the delayed bone healing and implant failure. In the past, a significant amount of research has been conducted to understand and mitigate the issues in bone drilling. However, the current practice in bone drilling is that medical surgeons still rely on their own experience and feeling, which often causes unwanted damage to the bone. The present paper aims to provide a comprehensive review of surgical bone drilling and impending factors affecting drilling and biological performance of the bone. Current protocols and practices in tackling issues around drilling are discussed and assessed in terms of results obtained in both experimental and computational domains. This pragmatic discussion will signify the importance and challenges ahead in empowering medical surgeons to enable improved surgical outcome. Furthermore, the findings of this extensive review are expected to drive further exploration of new opportunities for developing advanced bone drilling system integrated with intelligent sensors and control technology.
Rate Controlled Constrained-Equilibrium Simulation of Ethanol Combustion Using SVD Derived Constraints
Authors: Roy Shrabanti , Hadi Fatemeh , Askari Omid 
Published: January 2020

Abstract
In this study, the fully automatable Approximate Singular Value Decomposition of the Actual Degrees of Disequilibrium (ASVDADD) method is used for combustion modeling of ethanol. Due to the importance of ethanol as one of the most common type of biofuels, modeling its reaction kinetics and chemical composition evolution during combustion is necessary. The detailed kinetic mechanism (DKM) considered here is generated by authors using reaction mechanism generator (RMG) technique and it consists of 66 species and 1031 reactions. Tracking this number of species and chemical reactions in computational fluid dynamic (CFD) analysis of engineering problems is prohibitive. To alleviate this issue, Rate-Controlled Constrained-Equilibrium (RCCE) model reduction scheme for chemical kinetics is employed. It describes the evolution of a complex chemical system with acceptable accuracy with a number of rates controlling constraints on the associated constrained-equilibrium states of the system, much lower than the number of species in the underlying DKM. Successful approximation of the constrained equilibrium states requires accurate identification of the constraints. One promising procedure is the ASVDADD method that is capable of identifying the best constraints for a given range of thermodynamic conditions and a required level of approximation. ASVDADD is based on simple algebraic analysis of the results of the underlying DKM simulation and is focused on the behavior of the degrees of disequilibrium (DoD) of the individual chemical reactions. In this paper, ASVDADD is used to derive the RCCE constraints and ethanol combustion is modeled using both DKM and RCCE. Comparison of RCCE results with those of DKM shows the effectiveness of the ASVDADD derived constraints which demonstrates the potential of the RCCE method for combustion modeling of heavy and complex fuels.
Motorcycle No Fall Over Kickstand
Authors: Salman Muhammad 
Published: January 2020

Abstract
Motorcycles have been a mode of transportation since 1894, when the first batch of motorcycles were manufactured for consumer use by Hildebrand & Wolfmüller. Motorcycles provide a fast and cost effective, specifically fuel economy, way to commute. They are also used in recreational settings such as motocross and performance racing activities. Over the years, there have been many different design generations for the various manufactures and custom shops. The customer demand for motorcycles is always increasing as well. However, the biggest drawback to someone owning and operating a motorcycle has always been safety concerns. One of these safety concerns is the motorcycle falling over and being damaged while being parked. Fall overs occur for a multitude number of reasons, the most common occurrences due to being parked on an uneven level or someone pushing the motorcycle over. Current safety devices to prevent this from occurring are crash bars and center stands. However, these devices are either not applicable to all motorcycle makes and models or do not appeal to the motorcycles look per the owner’s discretion. A “no fall over” automated mechanical kickstand would solve both of these problems and, at the same time, prevent fall over accidents.
Singular Perturbation Solution for a Two-Phase Stefan Problem in Outward Solidification
Authors: Xu Minghan , Akhtar Saad , Alzoubi Mahmoud A. , Sasmito Agus P. 
Published: January 2020

Abstract
Mathematical modeling of phase change process in porous media can help ensure the efficient design and operation of thermal energy storage and pipe freezing. Numerical methods generally require high computational power to be applicable in practice. Therefore, it is of great interest to develop accurate and reliable analytical frameworks. This study proposes a singular perturbation solution for a two-phase Stefan problem that describes outward solidification in a finite annular space. The problem solves cylindrical heat conduction equations for both solid and liquid phases, with consideration of a moving boundary condition. Perturbation method takes the advantages of small Stefan number as the perturbation parameter, which intrinsically occurs in porous media. Furthermore, a boundary-fixing technique is used to remove nonlinearity in the moving boundary condition. Two different time scales are separately expanded and evaluated to facilitate the construction of a composite asymptotic solution. The analytical solution is verified against a general numerical model using enthalpy method and local volume-averaged thermal properties. The results indicate that the temperature profile of both phases can be well modeled by singular perturbation theory. The analytical solution is found to have similar conclusions to the numerical analysis with much lesser computational cost.
Influence of Vibration Characteristics of Agricultural Tire on Transfer Characteristics of Lug Excitation Force and Shaft Force
Authors: Fujita Katsuhide , Saito Takashi , Kaneko Mitsugu 
Published: January 2020

Abstract
The objective of this study is to clarify the vibration generation mechanism of agricultural machinery caused by the interaction between the tire lugs and the road surface. It is important to investigate the lug excitation force occurring on a rolling agricultural tire in order to clarify the vibration generation mechanism. In our previous study, we modelled the agricultural tire as a three-dimensional rigid ring model (SWIFT model). Further, the frequency equations of SWIFT model are derived and the model parameters are identified by minimizing the difference between measured and calculated natural frequencies. In order to identify lug excitation force, shaft displacement and shaft force during rolling motion are measured three-dimensionally by rolling test and lug excitation force in longitudinal, vertical and lateral direction are identified. From the obtained results, shaft force characteristics and lug excitation force characteristics are investigated. As a result, there is a correlation between shaft force and lug excitation force and it has been confirmed that both characteristics are influenced by the vibration characteristics of the tire. However, the transfer characteristics between lug excitation force (as input) and shaft force (as output) are not investigated.
In this study, amplitude magnification and phase difference are analyzed as the transfer characteristics of lug excitation force and shaft force. From the obtained results, the influence of vibration characteristics of the tire on transfer characteristics are investigated.
Biomechanical Structural Effect of Pinball Region Contact Applied to a Finite Element Model of Human Foot
Authors: Vidal-Lesso Agustín , Lara-Velázquez Carlos , Bayod-López Javier , Becerro de Bengoa Vallejo Ricardo , Mancera Campos Natali 
Published: January 2020

Abstract
Developing a finite element model of the human foot to analyze the numerical effect of the contact between its bones can also help to understand the complex biomechanics of this member.
Therefore, in this work, a three-dimensional model of finite elements of the foot is developed, in order to determine the contact radius between each pair of bones, which help to achieve an adequate distribution of body weight and be able to perform a correct characterization of the biomechanical effect of the foot. In the finite element model developed in this work, the cartilage was replaced by the pair of contact between two bodies (bones) and was simplified to the bony and ligamentous system. It was observed that the radius of the contact sphere of the pinball region has a great impact on the distribution of reactions with the ground (GRF) and the general behavior of the simulation. By varying the contact parameters, it was possible to reduce the error of the results obtained by the simulation with respect to those obtained experimentally up to a value of less than 5%; emphasizing the importance of checking the contact parameters before continuing with a simulation of finite elements.
The Highly Turbulent Flow and Heat Transfer in Semi-Closed Rotating Disc Cavity
Authors: Luo Guohu , Yao Zhenqiang , Wang Shengde , Shen Hong 
Published: January 2020

Abstract
The highly turbulent flow and heat-transfer in a semi-closed rotating disk cavity is numerically simulated based on a hybrid RANS/LES turbulence model. The superimposed radial outflow, which enters into the cavity from the inlet and exits the cavity from the discharge holes, results in the three flow region formed in the disk cavity. The effects of rotating Reynolds’ number and cavity aspect ratio on the pumping mass flow, local momentum coefficient as well as radial heat-transfer coefficient are fully examined. And the corresponding correlations are established with respect to rotating Reynolds’ number and aspect ratio. It is revealed that the radial heat-transfer from the periphery of the cavity to discharge hole is highly correlated to the secondary flow pumped by the rotating disk. Based on those prediction models, an equivalent thermal network for the radial heat-transfer is proposed, which can efficiently predict the radial temperature distribution in the semi-closed disk cavity, and estimate the effects of viscous-heating as well as temperature-viscosity correction.
Evolution of Liquid and Gas Phase Functional Groups During the Distillation Process of an Aviation Fuel
Authors: Luo Lei , Chen Shuqing , Liu Yu Cheng 
Published: January 2020

Abstract
Some surrogate fuel models have been formulated based on gaseous combustion properties. While development of surrogate fuel for spray combustion is still in an exploratory stage, it is in a great demand to develop methods to validate the volatility performance and corresponding combustion properties of a surrogate fuel mixture based on real fuel’s behavior. Distillation experiment of Chinese aviation fuel RP-3 was carried out to reveal evolution of components and chemical functional groups during the vaporization process of a real fuel. Both liquid and vapor samples were analyzed using GC-MS and NMR. The variation of functional groups and volatility performance of surrogate were also investigated using a well-validated numerical model. The experimental results show that the chemical functional groups almost have no change and that the average carbon number in the gas phase increases throughout the distillation. On contrary, the functional groups of some existing surrogates varied greatly during their distillation processes in spite that their distillation curves match well with real fuel’s. A 24-component mixture is formulated to demonstrated possibility to match both distillation behavior and combustion properties during vaporization. This study provides some potential directions for developing a surrogate with its vaporization truthfully representing the vaporization of the target real fuel.
Performance Analysis of the Impeller of a Centrifugal Air Compressor
Authors: Jebieshia T. R. , Raman S. K. , Kim H. D. 
Published: January 2020

Abstract
The present study focuses on the aerodynamic performance and structural analysis of the centrifugal compressor impeller. Performance characteristics of the impeller are analyzed with and without splitter blades by varying the total number of main and splitter blades. The operating conditions of the compressor under centrifugal force and pressure load from the aerodynamic analysis were applied to the impeller blade and hub to perform the one-way Fluid-Structure Interaction (FSI). For the stress assessment, maximum equivalent von-Mises stresses in the impeller blades are compared with the maximum allowable stress of the impeller material. The effects of varying pressure field on the deformation and stress of the impeller is also calculated. The aerodynamic and structural performance of the centrifugal compressor at 73000 rpm are investigated in terms of the efficiency, pressure ratio, equivalent von-Mises stress, and total deformation of the impeller.
Experimental Investigation of Spontaneous Buckling-Driven Delamination of Thin Films on Soft Spherical Substrate
Authors: Saito Yusaku , Yoshioka Shuhei , Emori Kanako , Teoh Rui Ern Brenda , Yonezu Akio 
Published: January 2020

Abstract
This study develops a new experimental system to investigate surface buckling patterns that emerge due to the biaxial compression of elastomeric bilayer spherical shell. The sample used in this study is a thick PDMS (polydimethylsiloxane) substrate and a thin PDMS film. In order to induce biaxial strain to the surface of PDMS substrate, air pressured device like bulge test is first developed. This system enables a flat PDMS plate to isotropically expand and become a hemisphere due to air pressure. In other words, the surface of PDMS substrate is stretched and subjected to biaxial loading. Subsequently, a thin PDMS film is covered on the hemisphere substrate. By releasing the air pressure, the pre-stretch in the substrate is released gradually and the outer film is subjected to biaxial compression. During the biaxial compression, various film buckling patterns are observed. It is found that the surface buckling patterns are wrinkle formation that is associated with film delamination. This formation pattern is dependent on the surface strain distribution, i.e. radial strain and circumferential strain. In order to control the pattern of buckling-delamination, we systematically changed the material parameters, such as the film thickness, Young’s modulus, interfacial fracture toughness, etc. Our experiment is capable in reproducing various wrinkle patterns with film delamination on an elastomeric bilayer spherical shell.