bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Integrative and Transdisciplinary Approach for a Human-Centered Design of AI-Based Work Systems
Authors: Schlicht Larissa , Melzer Marlen , Rösler Ulrike , Voß Stefan , Vock Silvia 
Published: January 2022

Abstract
Psychological and ethical criteria are to date not systematically covered in the system design process. We suggest to extend existing model-based system engineering approaches by new elements that are capable to capture these criteria and, in particular, allow for an implementation of psychological risk analysis and ethical evaluation of work systems already in the design phase.
The need for a systematic integration of not only safety but also ethical and psychological criteria in the system design is strengthened by the growing complexity of work systems and the increasing use of artificial intelligence-based algorithms, which have the potential to replace distinctive human capabilities and are associated with a shift of responsibility from humans to machines.
We identify essentially two factors impeding the development of an innovative integrative system design approach. First, at present, there is no legally predefined iterative process including an open feedback loop between the operator and the system designer that enables continuous risk assessment.
Second, available methods do not provide a framework to integrate ethical and psychological criteria.
We propose four steps for the development of an integrative system design approach: (1) an in-depth investigation of current methods suitable for holistic system design processes, (2) the development of a transdisciplinary terminology, (3) the development of a procedure which allows to identify ethical criteria meeting both individual and societal requirements and (4) testing of the developed approach in a digital system model by using a suitable use case.
Leveraging Vibrations and Guided Waves in a Human Skull
Authors: Kohtanen Eetu , Mazzotti Matteo , Ruzzene Massimo , Erturk Alper 
Published: January 2022

Abstract
This work is centered on high-fidelity modeling, analysis, and rigorous experiments of vibrations and guided (Lamb) waves in a human skull in two connected tracks: (1) layered modeling of the cranial bone structure (with cortical tables and diploë) and its vibration-based elastic parameter identification (and validation); (2) transcranial leaky Lamb wave characterization experiments and radiation analyses using the identified elastic parameters in a layered semi analytical finite element framework, followed by time transient simulations that consider the inner porosity as is. In the first track, non-contact vibration experiments are conducted to extract the first handful of modal frequencies in the auditory frequency regime, along with the associated damping ratios and mode shapes, of dry cranial bone segments extracted from the parietal and frontal regions of a human skull. Numerical models of the bone segments are built with a novel image reconstruction scheme that employs microcomputed tomographic scans to build a layered bone geometry with separate homogenized domains for the cortical tables and the diploë. These numerical models and the experimental modal frequencies are then used in an iterative parameter identification scheme that yields the cortical and diploic isotropic elastic moduli of each domain, whereas the corresponding densities are estimated using the total experimental mass and layer mass ratios obtained from the scans. With the identified elastic parameters, the average error between experimental and numerical modal frequencies is less than 1.5% and the modal assurance criterion values for most modes are above 0.90. Furthermore, the extracted parameters are in the range of the results reported in the literature. In the second track, the focus is placed on the subject of leaky Lamb waves, which has received growing attention as a promising alternative to conventional ultrasound techniques for transcranial transmission, especially to access the brain periphery. Experiments are conducted on the same cranial bone segment set for leaky Lamb wave excitation and radiation characterization. The degassed skull bone segments are used in submersed experiments with an ultrasonic transducer and needle hydrophone setup for radiation pressure field scanning. Elastic parameters obtained from the first track are used in guided wave dispersion simulations, and the radiation angles are accurately predicted using the aforementioned layered model in the presence of fluid loading. The dominant radiation angles are shown to correspond to guided wave modes with low attenuation and a significant out-of-plane polarization. The experimental radiation spectra are finally compared against those obtained from time transient finite element simulations that leverage geometric models reconstructed from microcomputed tomographic scans.
Wet Gas Hydrocarbon Centrifugal Compressor – Performance Test Results and Evaluation
Authors: Mæland Dagfinn , Bakken Lars E. 
Published: January 2022

Abstract
In the oil and gas industry a large portion of the compressor feed streams are characterised as wet gas, with a liquid volume content of between zero and five percent. Typically, this liquid is separated upstream of the compressor and handled separately. Such compressor systems have a large footprint, high weight, and high cost. In addition, if the liquid separation is not sufficiently good, trace amounts of liquid will enter the compressor and eventually cause fouling and performance degradation and possibly mechanical damage. The promising technology of wet gas compression is attractive to the oil and gas producers as it attempts to simplify the compressor systems thus reducing the footprint, weight, and cost. Furthermore, if the liquid amount is always sufficient to allow for liquid at the compressor discharge, fouling will not occur as the machine is continuously washed. This can allow for wet gas compressors continuously operating for years without any interventions. Installing such a wet gas compressor near the well head will provide increased recovery from the reservoirs.
Wet gas compressors are designed and used in a variety of operating conditions. Dependent on reservoir depletion, well stream compressors experience a gradual shift in inlet pressure and fluid behaviour. A major challenge both to designers and operators of wet gas compressors, is related to the impact of changing fluid conditions, such as gas mass fraction and density ratio, on performance.
Several single stage, two stage and multistage wet gas compressor test campaigns have been conducted at K-Lab. A large range of inlet conditions has been tested, i.e. inlet pressure ranging from 12 to 110 bar, gas mass fraction between 0.7 and 1.0, and combinations of hydrocarbon gas, hydrocarbon liquid, and water have been used as test fluids.
Performance test results from one of these wet gas test campaigns are presented in order to expose the impact of variables such as the fluid density ratio. The reference full-scale tests were conducted in real conditions i.e. realistic hydrocarbon composition, pressures, and temperatures. A large range of suction pressures were investigated, with a gas mass fraction ranging from 0.7 to 1.0. The density ratio between gas and liquid is of great importance as it relates to the flow regime, phase segregation and phase slip. Special emphasis is made to relate the performance shift between dry and wet conditions to the density ratio and other wet gas parameters, and a model is proposed that will incorporate these parameters to this shift.
Optimization of Injection-Molding Parameters for the Warpage of Green Parts of Metal Injection Molding by the Taguchi Method
Authors: Chung Chen-Yuan , Chen Yu-Peng 
Published: January 2022

Abstract
Historically, metal injection molding (MIM) is a fairly new injection-molding technique; it can realize parts with a complex exterior that are otherwise highly difficult to produce and thus remarkable widen the scope of powder metallurgy application. MIM has been applied to the production of precision metal parts due to its advantages of high productivity and high complexity. MIM has been developed as a powerful method for manufacturing high value-added metal components. Control of the injection-molding process is crucial. The combination of feedstock, which is composed of a binder and metal powder, also complicates the rheological behavior. Therefore, powder–binder separation often occurs during the filling stage. Injection-molding simulation is an effective tool for predicting the molding process.
The procedure for analysis has two major steps. First, flow front simulation is performed to validate the experimental short-shot results. Second, the experimental design of the Taguchi method is adopted to determine the optimal process parameters to reduce the green parts’ warpage. This approach eliminates the inherent uncertainties when operators have different levels of experience.
The short-shot results demonstrate that the simulated flow front is similar to the experimental one. Furthermore, the position of the weld line can be well predicted. The Taguchi method for minimized warpage shows improved dimensional precision. Moreover, the optimal process parameters can reduce the cycle time of three seconds compared with the original process parameters, which significantly benefits dimensional precision and the production rate.
Modeling Air Flow in Pathological Human Airway With Patient Specific CT-Data
Authors: Islam Adnan , Rouhollahi Amir , Lauria Michael , Santhanam Anand , Ilegbusi Olusegun 
Published: January 2022

Abstract
This study investigates the effects of different pathological conditions of human trachea on flow distribution in the tracheo-bronchial tree (TBT) of human airways. Pathological conditions including hereditary Left Pulmonary Artery Sling (LPAS) and Chronic Obstructive Pulmonary Disease (COPD) often cause stenosis in the tracheal airway while a widening of the airway has been reported for patients with pulmonary fibrosis. This study assesses the airflow distribution in the human airway under such pathological conditions relative to normal flow condition, utilizing Computational Fluid Dynamics (CFD). Realistic 3D airway geometry is first reconstructed from anonymized CT scan data of human respiratory system and used for the CFD analysis. Specific pathological conditions are simulated by the modification of the tracheal geometry to account for the consequent shape deviation, and the resulting flow in the central airway is analyzed. Different breathing conditions (rest and mild activity) are modeled by imposing appropriate boundary conditions. The results demonstrate marked dependence of the predicted flow distribution and wall shear stress in the trachea on the pathological conditions. Tracheal stenosis exhibits mass flow split between the right and left bronchi similar to healthy case while bronchial stenosis significantly changes the mass flow split with less air coming out of the left main bronchus compared to the healthy case. The next phase of the study aims to assess the effect of the upstream vessel obstruction on the spatio-temporal airflow distribution in the lung and the overall breathing pattern. Such capabilities will directly address the regional flow distribution associated with diseases such as COPD and LPAS.
Heat Sink Optimization for Collection of Potable Water Using Renewable Energy
Authors: Amaya Luz A. , Broderick David J. 
Published: January 2022

Abstract
Access to potable water remains a challenge for people in many areas of the world. Access to potable water during a natural disaster is made more difficult. The energy cost of delivering water to areas where infrastructure is damaged makes sourcing water locally advantageous. However, there remains an energy cost whether it results from desalination, purification, or condensation.
This work extends previous work to provide a potable water source that condenses atmospheric moisture using thermoelectric cooling modules. Improving the efficiency of such a device so that both energy and moisture can be sourced locally will lead to a reliable continuous source of water that does not rely on a supply chain.
One aspect that affects the efficiency of the device is the heat sink design on the hot-side of the thermoelectric cooling module. This works presents, analyzes, and tests four heat sink designs based on thermal performance and overall efficiency. None of the heat sinks meet all criteria appropriate for the application though a combination of factors are used to determine which is best suited. Consideration of mass, cross-sectional area, experimental temperature differential and water collection are compared with the overall surface efficiency determined from computational fluid dynamic simulation lead to the selection of the most appropriate heat sink.
Renewable Energy Production by Solar Chimney: The Influence of Curved Guide Vanes on the Performance of a Solar Chimney Using CFD Simulation
Authors: Xue Haokun , Esmaeilpour Mehdi 
Published: January 2022

Abstract
This study uses Computational Fluid Dynamics (CFD) to investigate the effect of guide vanes on power output of turbine installed in a solar chimney. A full scale three-dimensional CFD simulation of solar chimney power plant based on Manzanares prototype is performed to simulate the air flow inside the solar chimney. First, the flow field is simulated in presence of guide vanes with no turbine inside the chimney. Three guide vanes with different tip angles of 30°, 60° and 90° are considered. It is observed that the presence of guide vanes significantly affects the flow direction and the heat stored inside the blade chamber. Moreover, the change in output power of solar chimney under different turbine rotational velocities and different guide vanes is studied. A twelve-blade turbine is placed right above the exit of the guide vanes at the start of chimney. Various cases including three angles, 30°, 60°, and 90° guide vanes, and three rotational velocities, 40, 80, and 120 rpm are run to find output power. The Multiple Reference Frame (MRF) method is used to treat the rotation of the turbine. The analysis of power output of the turbine shows that the maximum power of 82.2 kW is reached by the case of 30° guide vane at 80 rpm. Comparing to the power of the 90° guide vane at the same rotational velocity, which is 66.3 kW, the increase is about 23.9%.
Performance of a Two Stage Electrohydrodynamic Gas Pump With Different Polarities
Authors: Monayem H. Mazumder A. K. M. , Robin Shariful A. , Wood Margaret 
Published: January 2022

Abstract
In this study, fluid flow induced by a two stage electrohydrodynamic (EHD) gas pump in a square channel has been evaluated by experimental measurement and numerical simulations. This study is implemented by a two stage EHD gas pump with different polarities for 24 emitting electrodes configuration to seek the relation between the number of stages and polarities. The EHD pump is evaluated for a wide range of operating voltages starting from 20 kV up to 28 kV for further improvement in its performance. To achieve the maximum enhancement, the emitting electrodes of the EHD gas pump are flush mounted on the channel walls so that the corona wind produced directly disturbs the boundary layer thickness and improves the heat transfer. This is leading to a higher velocity near the channel walls and resulting in an inverted parabolic velocity profile at the center of the channel, which is opposite to the fully developed velocity profile of a forced flow. Velocities are measured at three cross-sections along the tube length and then integrated to obtain the volume flow rate. The results show that EHD technique has a great potential for many engineering applications.
Compression Molding of Reinforced Plastics Using the Element Free Galerkin (EFG) Method
Authors: Medikonda Sandeep , Srivastava Ashutosh , Shejwal Amogh , Meena Rajesh 
Published: January 2022

Abstract
Composite materials using long fiber-reinforced plastics have seen increased usage in recent times due to their lightweight and better energy absorption characteristics. Compression molding, a high-volume, high-pressure method suitable for molding complex, high-strength fiberglass reinforcement plastics has been widely accepted in the manufacturing industry as an efficient process to mass-produce complicated shapes in a short time. Hence, it is of paramount importance to make this manufacturing process cost-effective and environmentally sustainable. To accomplish this, it becomes very important to understand different behaviors such as the fiber orientation, deformation, axial forces acting on the fibers, stresses occurring in the matrix, punch reaction force, etc. and the use of simulation-led design can help accomplish this with a high degree of accuracy.
Considering the extreme high-pressure conditions that the reinforced plastics are subjected to, traditional finite element (FEM) numerical approaches tend to fall short when it comes to compression molding primarily due to severe mesh distortion. In this context, the EFG method has been considered in the current work. EFG, like FEM, is a spatial discretization method however is based on a particle-based approach. The domain of interest is decomposed into material particles and the support domain uses polynom functions to approximate field variables similar to the shape functions used in FEM. Additionally, a background mesh is typically used to integrate the weak forms for the momentum balance. A combination of this theoretical background of EFG, which minimizes the inherent mesh distortion limitation encountered in FEM, coupled with the ability to handle reinforcements and an adaptive mesh refinement method makes this approach suitable for compression molding applications.
In this work, an approach to simulate the blank compression with and without fiber reinforcements using the EFG method has been presented. A separate implicit analysis was also carried out to calculate the spring back state of the non-reinforced model to identify the locations of the residual stresses. A 5-layer fiber-reinforced model with an orientation of [0/-45/90/45/0] was embedded into the matrix and the effect of the coupling behaviors between fibers and the matrix on the end deformed shape has also been studied. Primarily, the effect of having no axial resistance for the slip of the fibers versus defining a user-defined slip criterion on the wrinkling behavior has been compared. The approach presented in this work has shown great promise in simulating the compression molding of long fiber reinforced plastics.
Journey Mapping the Virtual Prototyping Experience
Authors: Moore George , Rao Vivek , Agogino Alice M. , Goucher-Lambert Kosa 
Published: January 2022

Abstract
Reframing failure, individual problem solving, and access to technology are signatures of the “maker movement,” which directly inspired university makerspaces across the globe. In particular, university makerspaces have become a significant resource to students taking courses that require the creation of tangible prototypes. While research investigating a student’s experience prototyping in a makerspace is growing rapidly, not much has been done to investigate the student prototyping experience in exclusively virtual settings. The goal of this study is to identify trends in the virtual prototyping experience with intentions of informing university instructors, makerspace facilitators, and students of where to anticipate struggles and frustration with the virtual prototyping experience. This study uses journey maps (a qualitative design method) to investigate the virtual prototyping experience for 12 undergraduate students, of diverse academic disciplines, at an R1 university in the United States. Results from this study suggest that the functional prototyping experience (which emphasizes independent contributions towards a tangible product) generates more emotional volatility than the experiential prototyping experience (which emphasizes collaborative efforts toward a final prototype). Other notable results include statistically significant differences between Female and Male self-reported emotional levels at the beginning of the experiential prototype journey.
Thermal Performance of a Helical Steel Energy Pile Incorporating Latent Thermal Energy Storage for Ground Source Heat Pump Applications
Authors: Mwesigye Aggrey , Shingledecker Ethan , Walz Andrew , Dworkin Seth B. 
Published: January 2022

Abstract
Ground source heat pump systems (GSHPs) have the potential to meet building space heating and cooling needs with significantly higher efficiencies. Using the relatively stable deep ground temperatures, GSHPs can reach efficiencies between 400–600% compared to 90% with advanced gas boilers. However, despite these high efficiencies, GSHPs are not widely used, mainly due to the associated high up-front costs. In addition, ground thermal imbalance when heating and cooling loads vary reduces GSHP performance and might result in eventual failure. Coupling ground heat exchangers with building foundations, an already existing structural element of the building, has potential to improve the cost competitiveness of GSHPs. In this study, the performance of a helical steel pile used as a ground heat exchanger for GSHPs is numerically investigated. A pile of 0.1298 m diameter and 20 m depth was considered in the analysis. Furthermore, the potential for improved performance using latent thermal energy storage with phase change material (PCM) was investigated. An organic PCM with a melting temperature of 6.5–8.5°C and a latent heat of 190 kJ/kg was used. A thoroughly validated numerical model of the helical steel pile was developed using a finite volume based computational fluid dynamics tool. With the use of PCM, considerable improvement in performance with an over 57% increase in the heat transfer rate per unit meter of the heat exchanger was achieved.
Nonlinear Robust Control Design for a Gravity Compensation Mechanism Under Human Walking Pattern Scenarios
Authors: Ilhan Zeki Okan , Chew Meng-Sang 
Published: January 2022

Abstract
Dynamics of a two degree of freedom suspension mechanism design is incorporated with a nonlinear robust controller to enable trajectory tracking under human walking pattern scenarios. To facilitate model-based control design, the system dynamic model is first extracted by applying Lagrange’s technique in non-conservative form. An inverse kinematic analysis is performed to transform a specific walking pattern trajectory in the workspace to the joint space to extract the target joint variables for control testing. An open-loop numerical simulation is also performed to demonstrate the sensitivity of the lifting force against the link inertia under dynamic conditions. Finally, the system dynamic model is incorporated with a feedback controller based on a nonlinear, sliding mode control strategy. The tracking performance of the proposed nonlinear controller is validated in closed-loop numerical simulations to demonstrate possible performance improvements under feedback control.
Geometric Performance Testing of Directed Energy Deposition Additive Manufacturing Machine Using Standard Tests for Machine Tools
Authors: Moylan Shawn , McGlauflin Michael , Tarr Jared , Donmez M. Alkan 
Published: January 2022

Abstract
While performance testing of additive manufacturing machines is still nascent, standard tests for performance of machine tools used in metal cutting are well established. Our hypothesis is that because directed energy deposition (DED) additive manufacturing machines physically resemble typical vertical machining centers, standard geometric performance tests for machine tools will directly apply to DED machines. Standard tests of positioning error motions and circular motion were successfully conducted on a commercially-available DED system. With all tests providing reasonable and expected results, there is nothing to falsify our hypothesis. One additional consideration is the need for testing of the Z-axis on additive manufacturing machines using target positioning intervals on the order of a typical layer thickness at several positions along the axis.