bluuebunny/crossref_metadata_2025 huggingface dataset:
Visualizing Fundamental Concepts Taught in Helicopter Dynamics Course Using Matlab Simscape GUI Program
Authors: Esquen Andrea Contreras , Martinez Jose Bonilla , Pena Paul , Khalid Adeel , Tekes Ayse
Published: January 2022

Students taking traditional undergraduate level engineering courses not only struggle with highly complex concepts but also struggle in linking the physical meaning of the derived mathematical equations. In this study, we developed a standalone and user-friendly Matlab Simscape Graphical User Interface (GUI) program to visualize the concepts presented in the undergraduate level helicopter dynamics course. The developed GUI program enables students to change the parameters of the blade including the rotor radius, blade chord, type of airfoil, material properties, the weight of the aircraft and analyze the effect of the parameter on the performance of the helicopter rotor. The program uses motion dynamics to simulate the blade movement in hover and forward flight. The Simspace GUI program is composed of four modules starting with a simplistic beam model. In the first module, the blade is considered as a simple cantilever beam where an input point load is applied at the tip of the blade either vertically down or at an angle. In the second module, the force is replaced by a radially distributed load that simulates lift distribution along the span of the blade. In the third module, the distributed load is applied to various types of airfoils ranging from symmetrical NACA airfoil to supercritical airfoils. In the fourth model, the sectional velocities vary as a function of azimuth, and the forward-moving rotor is simulated.
Mechanisms Design for the Hinge & Battery Lifetime Tests for a Prototype
Authors: Deemyad Taher , Akula Vincent , Sebastian Anish
Published: January 2022

In this paper, we design application specific mechanisms and control systems to test and deduce the lifetime of custom-designed hinges and batteries. These hinges and batteries are critical components of prototypes for a patented smart toilet seat. The work done here was used to improve the existing design and to identify a replacement cycle for these seat components. The target audience for this smart seat is airports and venues with large crowds. The smart seat has a cleaning solution that is contained within the seat in a cartridge, which can be easily replaced by facilities. The seat includes a motion sensor, battery, and slow hinges inside of it. This seat employs a slow hinge which reduces the impact of repetitive opening and closing of the seat. The hinge lifetime was tested and to this end a specific mechanism was designed. In this test, time required for opening seat, closing seat, and total number of opening/closing cycles the seat underwent was recorded. Also, in another experiment, the lifetime of the battery powering the pumping mechanism was tested until failure, where the battery voltage fell below a specific value and could no longer pump the cleaning solution out of the ports. Finally, the results for each experiment were compared for different samples and analyzed.
Design of an Affordable Prosthetic Arm Equipped With Deep Learning Vision-Based Manipulation
Authors: Imran Alishba , Escobar William , Barez Fred
Published: January 2022

Many amputees throughout the world are left with limited options to personally own a prosthetic arm due to the expensive cost, mechanical system complexity, and lack of availability. The three main control methods of prosthetic hands are: (1) body-powered control, (2) extrinsic mechanical control, and (3) myoelectric control. These methods can perform well under a controlled situation but will often break down in clinical and everyday use due to poor robustness, weak adaptability, long-term training, and heavy mental burden during use.

This paper lays the complete outline of the design process of an affordable and easily accessible novel prosthetic arm that reduces the cost of prosthetics from $10,000 to $700 on average. The 3D printed prosthetic arm is equipped with a depth camera and closed-loop off-policy deep learning algorithm to help form grasps to the object in view. Current work in reinforcement learning masters only individual skills and is heavily focused on parallel jaw grippers for in-hand manipulation. In order to create generalization which better performs real-world manipulation, the focus is specifically on using the general framework of Markov Decision Process (MDP) through scalable learning with off-policy algorithms such as deep deterministic policy gradient (DDPG) and to study this question in the context of grasping a prosthetic arm. We were able to achieve a 78% grasp success rate on previously unseen objects and generalize across multiple objects for manipulation tasks.
Parameter Optimization of a New Battery Model
Authors: Rose Cameron , Pence Ben
Published: January 2022

The lithium-ion battery (LiB) has become increasingly popular in electric vehicles (EVs), laptops, phones and many other devices that people use every day. It is popular due to its high energy density, low cost, lack of memory effect (typical of older battery types), longer life cycle (more full cycles till battery dies), and more. Because of its common use in everyday applications, knowing the state of charge (SOC) of a lithium-ion battery becomes an important problem to solve.

The first goal of this work was to develop and present a new battery model derived from fundamental principles of electrochemistry, Fick’s first law of diffusion, and a mass balance of lithium-ions between the anode and cathode. A voltage equation was developed based on the the open circuit voltage, the Nernst equation, and Ohm’s law. The battery model aims to accurately track the movement of lithium ions without being too computationally demanding, while the voltage equation relates the output of the model to the voltage of the cell. These equations are coupled and solved simultaneously. The SOC of the battery could then be determined based on the mass of lithium in the anode.

The second goal of this work was to optimize the parameters of the battery model to make it match experimental data. A cost function was defined and a genetic algorithm was implemented to minimize the cost function by altering the model parameters. The genetic algorithm successfully reduced the cost function. The model matched the experimental data and is therefore ready for commercial application.
Design, Prototyping, and Testing of a Robotic Prosthetic Leg Preliminary Results
Authors: Davidson Michael , Daher Noha , Fryer Thomas , Schaepper Johannes , Tran Duc
Published: January 2022

We report on our design and initial evaluation of a prototype robotic prosthetic leg (RPL) with a powered non-backdrivable knee and a hydro-pneumatic passive-resistive ankle. Our design was intended to increase health providers’ opportunities when offering their patients greater options, expanding the accessibility of advanced technology to those with lower functional levels of ambulation while decreasing the overall costs of care. The purpose of this biomedical device was to improve stance stability, increase balance confidence, and through powered-knee extension, reduce the contralateral limb’s kinetic stresses in gait, sitting, and standing. This device was designed to provide K2 and above ambulators a more adaptive, safe, and enhanced lower limb prosthesis. The prototype was assessed on a healthy subject while performing multiple 10-meter walk tests (10MWT) and six-minute walk tests (6MWT) on level-ground, inclines, and declines. We report walking velocity, the frequency of steps, cadence, falls, stumbles, toe-drags, battery consumption, and estimated torque of the knee actuator. We found the device safe on an able-bodied subject and feasible for future use on persons with limb loss.
Project Based Course Enabled Nanotechnology Education for Senior Level Undergraduate and Graduate Students
Authors: Dang Hongmei , Tyagi Pawan , Ososanya Esther , Klein Kate
Published: January 2022

National Science Foundation funding was obtained to nucleate nanotechnology curriculum and start a senior-level nanotechnology course cross-listed in the Mechanical Engineering and Electrical Engineering department. The key components are implementation of lectures integrated with hands-on laboratory experience, research seminar and evaluation. Laboratory projects of nanofabrication include metal-oxide-semiconductor capacitor and nano-structured solar cell for undergraduate and graduate students respectively. The assessment of course materials and master’s understanding was evaluated by surveys and direct observations of student performance. In spring 2020, statistical data from survey demonstrated that graduate students responded overall high rate for all of the course materials and undergraduate students gave high rate for majority of course materials except thermal evaporation fabrication project. A significant standard deviation for rating of thermal evaporation fabrication process indicated that practical engineering projects are challenging for some undergraduate students.
Structural Optimization for Segment-based Design of Part Candidates For Incremental Manufacturing
Authors: Redeker Julian , Vietor Thomas
Published: January 2022

The Incremental Manufacturing approach is based on a production concept, where products are assembled from mass-produced parts and finalized by additive and subtractive manufacturing steps. This approach promises economic variant production but also leads to increased complexity in product design and process planning due to the enhanced degree of freedom. Therefore, new methods and tools to support product development in the early design stages are investigated to exploit the production concept’s full potential.

In the context of redesigning parts for Incremental Manufacturing, a graph-based approach was introduced to support the design engineer in generating part concepts based on automated CAD model segmentation of a reference part. In this process, the extracted part segments are concretized based on algorithms, for example, by assigning predestined manufacturing processes, suitable pre-produced parts, materials, and joining technologies. For the concretization and early potential evaluation of the part candidate’s functionality in terms of mechanical performance, an optimization approach is introduced in this paper. This approach enables a combined structural optimization of part candidates with respect to the topology of additively manufactured areas and the shape of the pre-produced parts.
Pitch Angle & Decalage Effect in Biplane Blade Design for Wind Turbines
Authors: Atique Md Saifuddin Ahmed , Song Xueling , Yang Cai Xia
Published: January 2022

To reduce the environmental pollution and introduce new form of energy source, the popularity of harvesting energy from wind is increasing day by day. Wind turbines blades are growing longer, as increasing blade length is one of the best ways to produce more wind energy per turbine. However, longer blades require thicker root at the inboard section to counteract the bending load and this thicker root at the inboard section of the large wind turbine blades lower the blades aerodynamic efficiency. This loss of aerodynamic efficiency prevents these longer wind turbine blades from being fully effective as the cost to benefit ratio increases and less power is generated than the optimal value. Additionally, these long blades use a large amount of material. Longer blades require more support to remain structurally sound, which causes a large increase in mass. This material is hard to break down and decompose, causing them to take up a large amount of space in landfills when the blades are unserviceable or replaced because of damage and stress. To overcome this drawback and maximize the harvested energy from the wind, a novel “Biplane” shape wind turbine blade is proposed by the researchers which replaced the monoplane inboard section of the traditional wind turbine blades with the biplane inboard section. This new concept allows to design and manufacture longer wind turbine blade without any loose in aerodynamic efficiency and structural integrity. Biplane wind turbine blades have shown very interesting and promising characteristics in terms of both aerodynamics and structural performance. This new type of wind turbine blade can ensure more power, better aerodynamics efficiency, structural integrity along with lower manufacturing and transportation cost. Previous research conducted found the significant effect of gap and stagger in the aerodynamic performance of biplane blades. However, another very important parameter “pitch angle & decalage” that can improve the aerodynamic performance of biplane wind turbine blades remains unchecked. Keeping that in mind, the current research performed a detailed computational fluid dynamic (CFD) based analysis to find out the pitch angle & decalage effect in biplane wind turbine blade design. Our current research revealed that, apart from the contribution of gap and stagger, the effect of pitch angle & decalage can be significant. At a 6° angle of attack, with both top and bottom blade aerofoil pitch angle setup at positive (+ve) 3° which means decalage is 0°, can improve the lift coefficient (Cl) and the lift to drag ratio (Cl/Cd) or aerodynamics efficiency raised around 48% higher while gap to chord ratio (g/c) and stagger to chord ratio (s/c) were kept 0.5 and 0.25 respectively obtained from the previous state of art.
Dependencies of Parallel Sparse Iterative Linear Solver Methods on Matrix Conditioning on Unstructured Finite Element Meshes
Authors: Lu Qiyue , Koric Seid
Published: January 2022

Iterative methods are widely used for solving sparse linear systems of equations and eigenvalue problems. Their performances are relevant to the conditioning of the linear systems. This work explores factors which affects the conditioning of the discretized system, including material heterogeneity, different constitutive characteristics and element sizes, and reveals the dependencies among solvers performance and the conditioning of linear systems. Results show that multiple materials can alter the eigenvalue distributions significantly, while lowering Young’s modulus results in higher condition numbers but has less effects on the spectral scope, additionally, there is a approximately reciprocal square linear relation between element size and condition numbers. These entangled effects along with the chosen pre-conditioners render that there is no simple monotonic increasing dependency among condition numbers and solving time, except with specific conditions. It is hoped that this work will provide more understanding of the iterative sparse linear solver behavior used in similar structural problems.
The Evaluation of Tribological Performance of Laser Micro-Texturing Ti6Al4V Under Lubrication With Protic Ionic Liquid
Authors: Pang Junru , Guo Hong , Vázquez Martínez Juan Manuel , Salguero Jorge , Iglesias Victoria Patricia
Published: January 2022

Laser micro-texturing treatment has been proved as an efficient way to improve tribological properties of metal alloys. Meanwhile, ionic liquids also show great potential as novel lubricant additives to increase the durability of contacting components and decrease the energy loss during tribological process. This study investigated the influence of the laser micro texturing surfaces on the tribological performance of titanium alloy Ti6Al4V under different lubricant conditions. In this research, two sets of dimple-textured surfaces created by different laser parameters, energy density and area density, were fabricated on Ti6Al4V. Polyalphaolefin (PAO) 40 and 1 wt.% 2-hydroxyethylammonium 2-ethylhexanoate (Eet) used as additive to PAO 40 were designed as lubricants during the sliding tests. First, the geometrical properties of laser micro-textures on the surfaces were characterized. The wetting behaviors of different lubricants on textured surfaces were then examined based on contact angle measurement. All the frictional tests were carried out on the ball-on-flat reciprocating tribometer under the same working conditions. Lastly, the surface morphology of the wear tracks on Ti6Al4V and tungsten carbide balls and their wear mechanisms were evaluated by using the optical microscope, scanning electron microscope, and energy-dispersive X-ray spectroscopy. The results exhibit the laser micro-textures have a positive effect on improving the tribological performance of Ti6Al4V. Meanwhile, the use of Eet as the lubricant additive to PAO 40 can facilitate the formation of the tribo-layer, which enhances the tribological behavior of laser micro-texturing Ti6Al4V surfaces.
Using d15 Piezoelectric Transducers for Ultrasonic Inspection of Delamination in Laminated Structures
Authors: Altammar Hussain , Salowitz Nathan
Published: January 2022

A laminated beam consisted of internally embedded d15 piezoelectric transducers in a pitch-catch configuration was fabricated with artificial delamination created at the interface of aluminum layers. The severity of damage was also varied to evaluate the effectiveness of the approach to detect delamination. A five-peak tone burst signal centered at 30 kHz was supplied to piezoelectric actuators throughout the experiment to produce antisymmetric waves in the laminate specimen. It was found that the closer the delamination occurred to the d15 PZT actuator the greater the change in signal increasing the probability to be identified using antisymmetric A0 wave mode. The analysis suggests that d15 PZT actuators should be placed in regions where delamination is likely to occur in laminated structures. Also, the propagation path of delamination was successfully predicted using a set of sensor signals processed using damage index methods including Pearson correlation coefficient and root mean square deviation. Evaluation of the results indicated that embedded d15 piezoelectric transducers exclusively couple to antisymmetric guided waves and can advance signal analysis for detection of delamination with ultrasonic structural health monitoring systems.
Experimental and Numerical Investigation of Phase Change Material Melting at Suboptimal Inclines
Authors: Troxler Casey J. , Freeman Thomas B. , Rodriguez Rafael M. , Boetcher Sandra K. S.
Published: January 2022

Phase change materials (PCMs) are a key component to thermal energy storage solutions, which have the potential to hold a critical role in future energy storage. PCMs take advantage of large latent heat capacities as a method for storing thermal energy for later use. The research presented in this paper is part of an ongoing effort to document the melt behavior of lauric acid in an insulated rectangular container. This paper presents new experimental data of melting occurring at 180° and 135° incline. The data is processed to show the melt interface development and the melt fraction over the duration of the experiment. The results of the 135° incline experiment are compared to a numerical model and differences in results are examined.
Experimental Investigation on the Effects of Direct Fuel Injection Into Low-O2 Recompression Interval of an HCCI Engine
Authors: Sok Ratnak , Kusaka Jin
Published: January 2022

Gasoline direct injection (GDI) and negative valve overlap (NVO) are standard strategies to control combustion characteristics and exhaust gas emissions in homogenous charge compression ignition (HCCI) engines. In this work, experimental data from a single-cylinder engine operated under the GDI-HCCI mode were analyzed. The experiments were performed at an equivalence ratio of 0.95 under a mid-load condition. A side-mounted injector delivered primary reference fuel with octane number 90 directly into the combustion chamber during the NVO. The measured results showed advanced combustion phase CA50 under the early start of injection (SOI) timings. Peak recompression pressures were lower than the motoring, emphasizing that the NVO reactions were net endothermic. Zero-dimensional kinetics calculations showed that classical reformate species increase almost linearly as a function of SOI timings.

This work also presents the effects of intake boosting pressure and single versus double pulses injections on CA50, burn duration CA10-90, peak cylinder pressure, combustion noise metrics, thermal efficiency, and emissions. The combustion noise metrics were over the engine constraint limit under advanced SOI timings, but a double-pulse injection could reduce the combustion noise metrics and NOx emission. Late fuel injection in the intake stroke could reduce NOx to a single digit.
Effects of Laser Parameters on Printing Quality of Injection Mold Cores
Authors: Yang Can , Yang Bao-Hua , Li Chun-Bo , Deng Liang , Yang Ren-Xiu
Published: January 2022

The present work aimed at investigating the feasibility of product mass customization according to consumers’ needs, making full use of advantages of both the selective laser melting (SLM) and injection molding. For this purpose, a new type of cylindrical injection mold core with a diameter of 30 mm was designed. In this core, ear structures for assembly purpose were designed with different inclined angles (i.e., 45, 60 and 75°). As the first stage of the goal, in this paper all ear structures were 3D printed separately using the SLM machine (SLM Solution 125), and the printed angle accuracy and surface quality of the inclined surfaces were evaluated. It’s found that the angle accuracy of the 3D printed inclined surface is directly proportional to the designed angle of the ear structures. Meanwhile, the fringe laser re-melting strategy gave the smoothest surface of the printed components. For example, the roughness values for the top and inclined surfaces are 8.831 and 7.212 μm, respectively. As fully integrating the individualization of SLM and the batch production capacity of injection molding, this work will provide theoretical and experimental data support for the mass customization.
Design of an Efficient, Low-Cost, Stationary LiDAR System for Roadway Condition Monitoring
Authors: Bennett Jarod , Saladin Mather , Sizoo Daniel , Stewart Spencer , Wood Graham , DeAgostino Thomas , Depcik Christopher
Published: January 2022

Light Imaging Detection and Ranging (LiDAR) systems generate point cloud imagery by using laser light to measure distance to a surface and then combine numerous points to create a three-dimensional (3-D) image. Since early adaptations, LiDAR is now common in aerial and subterranean geographical surveying and autonomous vehicle operations. The transportation industry uses LiDAR to monitor roadway quality, which can allow hazardous roadway corrosion to be spotted and repaired before endangering drivers. However, a leading issue with LiDAR availability is the respectively high price point for effective systems, therefore preventing widespread usage.

Previous work at fabrication of a low-cost LiDAR system generated high resolution 3-D imagery but was faulted by limited portability and a long run-time while also finding issues with gimbal translation and C++ programming. This effort improves the prior work by combining a touchscreen Graphical User Interface (GUI) with a rangefinder (Garmin LiDAR-Lite v3HP) powered by Raspberry Pi 4 Model B hardware. The rangefinder is housed in a 3-D printed gimbal mount that translates via two stepper motors and driver board. The system runs via a Python script that allows the user to select varying levels of resolution on the GUI prior to data collection onto a Secure Digital card or a file accessible through an internet connection. Like the previous work, data output is in Cartesian coordinates through a .xyz file format with a MATLAB script used to create a point cloud and two-dimensional image with a depth gradient. Overall, a more efficient, easier to use, and accurate LiDAR system was created that offers various resolution levels for under the cost of $500.
Parametric Evaluation of Head Center of Gravity Acceleration Error From Rigid Body Kinematics Assumptions Used in Environmental Sensors
Authors: Brown Brandon A. , Daniel Ray W. , Chancey Valeta Carol , Rooks Tyler F.
Published: January 2022

Environmental sensors (ES) are a proposed way to identify potentially concussive events using Rigid Body Kinematics (RBK) to get motion at the head CG. This study systematically investigated the extent that errors in RBK assumptions including sensor orientation (SO), head CG position (HCGP), and exposure severity contribute to errors in sensor readings of predicted peak resultant linear acceleration (PRLA) at the head CG. Simulated sensor readings were defined by idealized representations of head motion [extension, lateral bending and axial rotation] using a half sine pulse for linear and angular acceleration. Peak magnitudes of linear acceleration ranged from 12.5 to 100 Gs and peak magnitudes of angular acceleration ranged from 1250 to 10000 rad/s/s. Durations of linear and angular accelerations ranged between 5 and 30 ms. Simulated HCGP variations ranged from −10% to 10% radius of the head (assumed to be a sphere) in each direction and SO variations ranged from −20 to 20 degrees about each axis. True head CG response was calculated using zero error for SO and HCGP. Mean (+/− standard deviation) of calculated errors for maximum percent error (MaxPE) of a given head exposure was 30.3% (+/−9.71). 50% and 38% of all simulated exposures had MaxPE associated with maximum SO and HCGP offset, respectively. MaxPE was likely due to user error, ES form factor, and anthropometric variation.
Approach for Modelling the Dynamic Transmission Behavior of Grinding Discs Using Transfer Functions
Authors: Dörr Matthias , Dürkopp Alexander , Zimprich Sebastian , Gwosch Thomas , Gittel Hans-Jürgen , Pelshenke Christian , Dültgen Peter , Matthiesen Sven
Published: January 2022

Knowledge of the forces acting on the drive train of a machine is important for testing and Design for Reliability. In the case of angle grinders, these forces arise primarily at the contact between the workpiece and the grinding disc. Previous state-of-the-art approaches can determine the dynamic tool forces. Thereby it remains unclear whether the dynamic tool forces also correspond to the dynamic forces on the drive train since the dynamic force transmission via a grinding disc is not taken into account. Therefore, this article shows an approach to how the transmission behavior of a tool can be modeled by transfer functions to calculate the load on the drive train from the tool forces. It is shown that transfer functions for constant operating points can be generated by a test rig in three force directions and that these transfer functions can be merged for different grinding discs. It is also shown that the load of the drive train differs from the load from the tool forces. This means that the transmission behavior of tools such as grinding discs must be taken into account when testing and Design for Reliability. With the chosen approach, a solution is shown how the load on a drive train can be determined via transfer functions of a grinding disc from tool forces.
Pulse Wave Velocity and Transmission at the Carotid Artery and the Ascending Aorta
Authors: Smith Sara M. , Marin Justine , Adams Amari , West Keith , Hao Zhili
Published: January 2022

With consideration of a full set of mechanical properties: elasticity, viscosity, and axial and circumferential initial tensions, and radial and axial motion of the arterial wall, this paper presents a theoretical study of pulse wave propagation in arteries and evaluates pulse wave velocity and transmission at the carotid artery (CA) and the ascending aorta (AA). The arterial wall is treated as an initially-tensioned, isotropic, thin-walled membrane, and the flowing blood in the artery is treated as an incompressible Newtonian fluid. Pulse wave propagation in arteries is formulated as a combination of the governing equations of radial and axial motion of the arterial wall, the governing equations of flowing blood in the artery, and the interface conditions that relate the arterial wall variables to the flowing blood variables. We conduct a free wave propagation analysis of the problem and derive a frequency equation. The solution to the frequency equation indicates two waves: Young wave and Lamb wave, propagating in the arterial tree. With the related values at the CA and the AA, we evaluate the influence of arterial wall properties on their wave velocity and transmission, and find the opposite effects of axial and circumferential initial tensions on transmission of both waves. Physiological implications of such influence are discussed.
Aerodynamic Analysis of Flat Plates as Lift Generating Devices for Micro Aerial Vehicles
Authors: Borah Bastav , Kulkarni Vinayak , Saha Ujjwal K.
Published: January 2022

With the advent of Micro Aerial Vehicles (MAVs) and their widespread applications, the use of flat plate as a lift generation device has drawn utmost attention, and therefore, it needs to be investigated further. Usually, fixed wing MAVs work in the range of Reynolds number, Re = 104–105, and it is reported that a flat plate shows a better lift-to-drag ratio in this range of Re as compared to conventional airfoils. This investigation aims to understand the aerodynamic characteristics of a flat plate at low Re and its applicability on fixed wing MAVs. In this regard, a two-dimensional computational study using the Spalart-Allmaras turbulence model is conducted to observe the flow around a flat plate for Re of 4.8 × 104 and 7.6 × 104. Two flat plates having thickness ratios of 1% and 3% are considered in the present study. In each case, the trailing edge vortices are studied and the corresponding Strouhal number is calculated. The general observation is that the Strouhal number decreases with the increase of angle of attack. The flat plate with 1% thickness ratio shows a better lift-to-drag ratio than the flat plate with 3% thickness ratio. The pressure distribution along the flat plate has also been plotted and compared to that of a conventional low Re airfoil, S5010. For the Re under investigation, the difference in pressure between the suction and pressure sides is found to be higher for the flat plate at higher AoAs.
Communications and Learning for DevOps (CALDO): A Framework for Leveraging Automation for Human Performance Support and Training Systems
Authors: LeBlanc E. J.
Published: January 2022

The Industry 4.0 paradigm and digital transformation, with the powers of automation and machine learning, are fundamentally changing what it means to manufacture goods and services. Across the globe, manufacturers and their work forces are scrambling to keep up. The Communications and Learning for DevOps (CALDO) framework strives to empower communications and learning professionals to thrive in DevOpsoriented environments by making the paradigm leaps necessary to embrace the opportunities Industry 4.0 provides. The purpose of this paper is to convey to human communications and learning professionals the principles of DevOps, define the broad array of communications and learning professionals working in manufacturing today, and describe the process of implementing the CALDO framework.
A Viscoelastic Tuned Mass Damper for Vibration Treatment of Large Structures
Authors: Al-Rumaih Wail S. , Kashani Ahmad R.
Published: January 2022

Viscoelastic (VE) tuned mass dampers (TMDs) using commercially available, small thickness, VE material have been used extensively in adding targeted damping to light structures. The most common approach for realizing stiffness and damping in these tuned devices has been applying VE material to strips of elastic material (mainly metal, e.g. steel) in an unconstrained or constrained layer fashion and using such assemblies, which can be viewed as a damped leaf-springs, for the suspension element of the tuned mass damper. In this work, the suitability of tuned mass dampers with visco-elastically damped leaf-spring suspension for treating large, massive civil engineering structures, more specifically floor systems, was studied numerically and experimentally. The effectiveness of this tuned mass damper configuration turned out to be disappointing.

In parallel to the above-mentioned study, an alternative VE suspension was devised by stacking a number of 25 mm (1 inch) thick VE rings interlaced with the same number of metal constraining ring layers. By changing the number of these rings, different stiffness’s are realized and thus different tuning frequencies are achieved.

The material properties of the VE polymer used in both studies are defined in terms of Prony series parameters. Viewing the Prony series parameters as optimization variables, they are recovered by minimizing the mean squared error between the dynamic material properties predicted by the Prony series parameters and the frequency-dependent dynamic material properties provided by the manufacturer. Using the material properties of the VE material, the dynamic finite element model of a 100 lb TMD was constructed and its tuned damping effectiveness demonstrated, numerically. The 100 lb TMD was also built and used to a) verify the numerical model and b) experimentally demonstrate the performance of the TMD.
Experimental Study of Heat Transfer Characteristics of Drying Process with Dielectrophoresis Mechanism
Authors: Yang Mengqiao , Asar Munevver Elif , Yagoobi Jamal
Published: January 2022

Drying of moist porous media, such as paper and pulp, is an extremely energy-consuming process. Traditional drying techniques are primarily associated with convection, conduction, and thermal radiation. It is desirable to develop innovations in non-thermal and high-efficiency drying techniques. In the previous study, a novel drying technology, making use of the Dielectrophoresis (DEP) mechanism, has been experimentally proved to be an energy-efficient method to enhance the drying rate of moist porous media. DEP is a translational motion of neutral matter caused by the polarization effects in a diverging electric field. During the drying process, in the presence of the DEP force, the vapor phase is extracted away from the porous medium, which results in an increase of the evaporation rate and a decrease of the sample surface temperature. This paper extends previous experimental studies by including analysis of the heat-transfer characteristics. Specifically, the heat flux rate underneath the moist paper is monitored during the drying process. The sample surface temperature is monitored through an Infrared (IR) camera. Moreover, the convection heat transfer coefficients are estimated, and the sample’s initial moisture content is studied as a function of drying time. The experimental results show an up to 132% increase of the heat flux rate and a 242% increase of the convection coefficient due to the application of an electric field, as compared to conventional drying process. The experimental results also illustrate that the DEP effects diminish at low moisture levels. The detailed heat transfer analysis provides a foundation for the enhancement of moist porous media using the DEP mechanism for drying fragile products.
The Role of Protective System Reliability Analysis in the Study of System Safety
Authors: Wortman Martin , Kee Ernie , Kannan Pranav
Published: January 2022

Safety–critical protective systems mitigate possible collateral harm to the public, when randomly occurring initiating events challenge the operational integrity of hazardous technologies. Quantifying the efficacy of protection remains a challenge to engineers and regulators responsible for safety. In this paper, we will explore the analytical relationship between protective system reliability and safety efficacy. Central to our discussions is the understanding that: Not only should protective systems be reliable over time, but they must be highly effective at the exact instants of initiating event arrivals. Extending traditional system reliability analyses to quantify the effectiveness of protective systems that are challenged by potentially catastrophic initiating events, requires identifying and redressing certain modeling pitfalls that are counterintuitive. It is our purpose, here, to reveal some of these pitfalls by appealing to well known results from system reliability theory and the theory of stochastic point processes.
Optimization of Powertrain Energy Management for Range Extended Electric Vehicle Using Modified Particle Swarm Algorithm
Authors: Parkar Omkar , Snyder Benjamin , Anwar Sohel
Published: January 2022

Energy and Power Management Strategies play vital role in improving efficiency of any hybrid propulsion system. However, these control strategies are sensitive to the dynamics of the powertrain components used is the given system. A mathematical model for hybrid powertrain of Range Extended Electric Vehicle (REEV) has been developed in this study and is further optimized to reduce the level of fuel consumption and NOx emissions individually by optimizing the control strategy of Power Management System (PMS). A modified Particle Swarm Optimization (PSO) algorithm has been used in this research, to determine the optimum PMS strategy. In performing these optimizations, the control signal consisting of genset speed and power for a full 2-hour cycle was used as the controllable decision parameters input directly from the optimizer. Each element of the control signal was split into 50 distinct points representing the full 2 hours giving slightly more than 2 minutes per point, noting that the values used in the models were interpolated between the points for each time step. With the control signal consisting of 2 distinct signals viz. speed and power, as 50 element time variant signals, a 100-D problem was formulated for the optimizer. The developed algorithms were simulated on the REEV model on MATLAB/SIMULINK platform. Simulation results show that the fuel consumption reduction of 12% and NOx emission reduction of 35% was achieved individually by deploying the optimal PMS strategy when compared with the baseline results.
Vision Based Obstacle Detection and Navigation of an Autonomous Vehicle
Authors: Nandikolla Vidya K. , Ferman Keven , Barragan Eddie , Fuentes Melgar Stefany , Perez Hector
Published: January 2022

Using the vision system, the autonomous vehicle detects and classifies objects with high accuracy and determines its navigation. The image files are transported into the robot operating system (ROS) to test in the simulation. Google’s TensorFlow and ImageAI computer vision Python library, are used to create a custom neural network model to detect and classify specific objects, i.e. lane lines to drive within or caution cones to avoid hazards. Initial development focused on processing and annotating two hundred images of a random object in various angles, distances, and light conditions recorded from the cameras on the autonomous vehicle. These images are processed through Google’s CoLaboratory, a cloud-based development server providing free GPU hardware, for faster processing. The goal is to take the customized detection model and provide a desired output. The test procedure included coding annotated pictures of different objects and creating datasets. The procedure for training the datasets are developed and as a result, several models for each of the objects are obtained. The object detection model with the best capability to detect designated objects were evaluated. The paper reflects how machine learning is utilized for obstacle detection and navigation for autonomous vehicle to maneuver around assigned constraints.
Dynamic Transition From Regular to Mach Reflection Over a Moving Wedge
Authors: Margha Lubna , Hamada Ahmed A. , Knight Doyle D. , Eltaweel Ahmed
Published: January 2022

The transition between the Regular Reflection (RR) and Mach Reflection (MR) phenomenon impacts the design of the supersonic and hypersonic air-breathing vehicles. The aim of this paper is to numerically investigate the dynamic transition from RR to MR of unsteady supersonic flow over a two-dimensional wedge, whose trailing edge moves along the x-direction upstream with a velocity, V(t) at a free-stream Mach number of M∞ = 3. The simulation is conducted using the unsteady compressible inviscid flow solver, which is implemented in OpenFOAM®, the open-source CFD tool. Further, the wedge motion is applied by moving the mesh boundary, performing the Arbitrary Lagrangian-Eulerian (ALE) technique. In addition, the sonic and the detachment criteria are used to define the dynamic transition from RR to MR during the increase of the wedge angle. Different reduced frequencies, κ, in the range of [0.1–2] for the moving wedge are applied to study the lag in the dynamic transition from the steady-state condition. The results show that the critical value of κ = 0.4 distinguishes between the rapid and gradual lag in the transition from RR to MR. In addition, the transition from RR to MR occurs above the Dual Solution Domain (DSD), since the shock is curved downstream during the rapid motion of the wedge.
Algorithm to Avoid Normal Tissue Sacrifice and Thermal Injury of Neighbouring Organs During Radiofrequency Ablation of HCC Tumours Treated Using a Multi-Tine Electrode With Separately Controlled Tines
Authors: Dhiman Manoj , Repaka Ramjee
Published: January 2022

Radiofrequency ablation of Hepatocellular Carcinomas lacks electrode level feature to (a) avoid the risk of thermal injury to the neighbouring organs and (b) avoid the sacrifice of normal hepatic tissue. The absence of such a feature causes additional intrusion of the human body to overcome the first problem, while there is no solution for the latter problem. An algorithm has been developed and implemented using an unconventional multi-tine RFA electrode to incur ablations specific to the shape and position of target tumours to solve these problems. Further, this algorithm can suggest the best insertion angle for the trocar, such that minimum normal tissue is sacrificed. This suggestion is made quickly with the help of a pre-simulated database. For verification of the algorithm, pre-segmented tumours have been used as inputs and damages incurred with and without algorithm have been compared.
Effect of Process Parameters on the Microstructure of Closed-Open Cross Wedge Rolling
Authors: Shu Xuedao , Wang Jitai , Han Sutao , Wei Yilun
Published: January 2022

Microstructure is one of the key factors determining the mechanical properties of an axle, which requires to obtain fine and uniform grain structure. This research work aims to explore the influence of different process parameters on the average grain size and distribution uniformity of the rolled piece during the closed-open cross wedge rolling (CWR) process, so as to improve the micro quality of the rolled piece by adjusting the process parameters. Firstly, an automobile oil pump axle made of 42Crmo is considered as a research object, and a 3D thermal-mechanical-microstructure coupled finite element model of closed-open CWR is established by adopting software DEFORM. Secondly, three points are uniformly selected along the central axis of the rolled piece as observation points, and the variation law of the average grain size at different positions with time is studied. Thirdly, the effects of the reduction of area, the diameter of the rolled piece, the forming angle of the wedge section and the stretching section on the average grain size of the rolled piece and the uniformity of the grain distribution are studied separately. Finally, combined with the closed-open CWR experiment, the influence of different billet diameter on the average grain size is consistent with the simulation results, which verifies the reliability of the model.
Performance Analysis of Zeotropic Organic Rankine Cycle for Marine Diesel Exhaust Heat Recovery
Authors: Gao Qizhi , Yuan Han
Published: January 2022

Marine diesel engine plays the dominate role on the merchant ship power supply field, which is responsible for 3.1% of global CO2 emissions. As one third of the energy is wasted along with the exhaust gas, heat recovery of marine diesel exhaust is an effective way of improving the thermal efficiency of entire power system. The temperature of marine diesel exhaust ranges from 250°C to 550°C, and this medium/low-grade heat source can be recovered by thermodynamic cycle technology. The Organic Rankine Cycle (ORC) is most commonly used in medium/low-grade waste heat recovery because of its simple structure. However, ORC utilizes the pure organic compound as the working fluid, and the evaporation of the pure organic compound experiences with isothermal and isobaric process, resulting in a relatively high temperature difference of heat transfer between the heating source and working fluid, which ultimately limits the thermal efficiency of ORC. In comparison, the Zeotropic Organic Rankine Cycle (ZORC), which utilizes the zeotropic mixture and working fluid, is proved competitive for the temperature slip phenomenon in its evaporation process. Besides, the heat transfer in the condenser will get worse due to the liquid accumulating on the condensation wall, leading to a larger heat exchange area requirement. Therefore, the liquid-separation condensation method is investigated to reduce the heat exchange area of condenser. In this study, both the multi-pressure evaporation and liquid-separation condensation processes are introduced to improve the ZORC performance. Working fluid selection for the ORC and ZORC with a wide range of marine diesel exhaust temperature is conducted, with corresponding evaporation temperature ranges between 100°C and 200°C. The proportion analysis for different kinds of zeotropic organic mixture is made to obtain the optimized working fluid under the given evaporation temperature by 200°C. Cyclopentane-toluene (0.55–0.45) can reach the highest efficiency with 19.76%. Moreover, thermodynamic analysis based on the first law and second law of thermodynamics are made to reveal the thermal efficiency, output work and exergy efficiency of these cycle, as well as the exergy destruction in each component. In addition, the dryness of mixture at the liquid-separation point in the condensation process, which reveals the position of the liquid-separation outlet in the condenser, is discussed. The results show that the major exergy destruction occur in the evaporation and condensation processes. With the assistance of multi-pressure evaporation and liquid-separation condensation processes, the exergy destruction in the heat exchangers is decreased by 17.09%∼21.61%.
Study on the Operation Strategy Based on Multi-Objective Optimization Considering Power and Emission Performance for a Gas Turbine
Authors: Li Bei , Chen Jinwei , Zhang Huisheng
Published: January 2022

The control strategy of a gas turbine is usually to maintain the turbine outlet temperature by adjustable inlet guide vane (IGV), thereby ensuring that the gas turbine operates in an efficient region, however, this method is difficult to optimize the power and emission performance simultaneously for the gas turbine at a specific operating power. In this study, a thermodynamic model suitable for the gas turbine dynamic performance and a NOx emission model based on least squares support vector machine are established, then the relationship between gas turbine thermal efficiency, emission and state trajectories is determined by a gas turbine multi-objective optimization method. The optimization framework adopts multi-objective particle swarm optimization algorithm, targeting efficiency and NOx emission, using operating power as a constraint to make the multi-objective analysis of the gas turbine operation process, which provides guidance for the development of multi-objective optimization control strategies for gas turbines.