bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crack in a Bimaterial Functionally Graded Multilayered Media
Authors: Muju Sandeep 
Published: January 2022

Abstract
The macroscopically anisotropic homogenization of a multilayered media implicitly assumes that the spatial wavelength of material inhomogeneity is smaller than the macroscopic quantity of interest and hence, is a reasonable approximation of the bulk behavior. However, close to the crack tip, gradients in field quantities are strongly influenced by the local heterogeneity, which the isotropic or anisotropic homogenization fails to capture.
The present work addresses the issues related to the influence of material inhomogeneity on local crack tip driving force. It is shown that to the first order, the effect of moduli inhomogeneity, residual stresses and inelastic strains on crack tip stress intensity factor are superposable.
Detailed analytical model is developed for quantifying the effect of moduli inhomogeneity for the case of bimaterial multilayered media with functional interfaces, i.e., compositionally graded finite thickness interfaces.
This method provides an efficient means to study thermoelastic crack problems in complex heterogeneous media, alleviating the numerical or analytical difficulties associated with the traditional methods. The results show that the material inhomogeneity plays a significant role in effecting the crack tip driving force.
Inputs for Successful Target Costing
Authors: Clifton Brad , Townsend Wes 
Published: January 2022

Abstract
Cost management is becoming as widespread as quality control was in the 1970’s and 1980’s1. Target Costing is an effective, structured approach to cost management. We have all faced the limitations of trying to reduce costs when a product is already designed and in manufacturing. This is the most expensive phase of the product realization cycle to make a change, so often good cost reductions ideas are not implemented. Target Costing addresses this limitation because it brings the strength of the whole enterprise into the early stages of a product’s development cycle.
Process Quality in Rapid Manufacturing
Authors: Kahlen Franz-Josef , Kar Aravinda 
Published: January 2022

Abstract
The subject of this presentation is the qualification of a rapid manufacturing process in terms of the created product. The analysis was based on using a high power CO2 laser as energy source for parts creation, material under investigation is Stainless Steel SS304. The incident CO2 laser beam power was varied from 300 W to 400 W, with the laser beam showing a Gaussian intensity distribution. The laser beam was focused to a focal diameter of 460 μm using a 127 mm (5“) focal length lens.
This study investigates, for a variety of operating conditions, the smoothness of the material deposition, the process’ inherent susceptibility to lateral misalignment, geometrical characteristics of the process, and the permissible yield and ultimate tensile strengths. The yield strength is close to isotropic (250 MPa, same as wrought SS304), despite the expectation that the joints between the layers would turn out as the weakest link in the chain, and height deviations were well within 10% of the deposition height for high powers and small substrate translation speeds. The impact of a lateral misalignment is comparable to values for other laser materials processing situations.
Design Optimization of Rolling Element Bearings
Authors: Fu Wen , Rhodes John H. , Good Bruce R. , Dong Jian (John) 
Published: January 2022

Abstract
This study presents an efficient method for optimizing Basic Dynamic Load Rating (BDLR) of rolling element bearings such as spherical roller thrust bearings. An optimizing model and program have been developed using the Solver feature within MS Excel. The program searches for the ideal combination of roller diameter, length and quantity to maximize BDLR within certain predetermined constraints. Results show that significant increases in load rating can be achieved when compared with existing designs in product offerings. This program thus enables the designer to efficiently create enhanced products while reducing the level of design experience required. This methodology is currently being applied to rolling element bearings manufactured by the Fafnir Division of The Torrington Company.
Design of a Computer-Aided Modeling System: A Case Study
Authors: Lotko John , Bzymek Zbigniew M. , Garrett Richard E. , Billatos Samir B. 
Published: January 2022

Abstract
This paper describes a computer algorithm capable of seamlessly transforming a Cadkey part into tool paths that can produce a model using a Computer-Aided Modeling (CAM) machine. This was accomplished utilizing rules based on known machining practices developed in conjunction with Cadkey and Cutting Edge designers. The rules used for designing this software consist of fundamental principles of machining. In the conventional approach, these are the rules that are supplied by the designer and applied to the problem using a programs such as Cutting Edge. The basic set of rules and the original Computer-Aided Design (CAD) design were sufficient to create the needed tool paths with the user’s time and input replaced by a computer algorithm. A developed computer algorithm is much less flexible, but significantly quicker than a designer, so where applicable more robust rules which required greater time or iterations were chosen. The algorithm is general but can be applied to any CAD system. However, the specific design work was performed with Cadkey as the target low cost system and a Roland desk-top Computer-Aided Modeling Machine (CAMM-3) as the target cutting device. All assumptions made for this test case were based on the criteria of user’s convenience and economy. All the tests performed proved that the algorithm works and is capable of adding one more output device — a cutter as an output system.
Sound Absorption of Solid-State PETG Foams
Authors: Lee Nathaniel , Reinhall Per G. , Kumar Vipin 
Published: January 2022

Abstract
The sound absorption characteristics of PETG foams have been investigated experimentally. The normal incidence sound absorption coefficient was measured using an impedance tube designed according to ASTM 1050-90. The effect of both the cell size and the density of the foam on the absorption coefficient were investigated. The absorption coefficient was shown to be sensitive to both these parameters. The larger cell size (800μm) foam exhibited a significant increase in absorption around 3700 Hz making the absorption coefficient highly dependent on the frequency content of the incoming acoustic energy. It is also shown that thin foam sheets can be layered to achieve an acoustic treatment with high absorption characteristics.
E/M Impedance Health Monitoring of Spot-Welded Structural Joints
Authors: Giurgiutiu Victor , Reynolds Anthony , Rogers Craig A. , Chao Yuh Jin , Sutton Michael A. 
Published: January 2022

Abstract
Experimental results obtained during fatigue testing of a spot-welded lap-shear structural-joint specimen are presented. In these experiments, the electro-mechanical (E/M) impedance technique was used for structural health monitoring, damage detection, and NDE. The test specimens were instrumented with piezo-electric wafer transducers, and the base E/M impedance signature was recorded over the relevant frequency range. Fatigue testing was applied to initiate and propagate crack damage of controlled magnitude. Preliminary tests were performed to correlate stiffness decrease with damage progression and remaining life. Then, during the health monitoring tests, the specimens were continuously monitored for stiffness decrease indicative of damage. E/M impedance signatures were periodically recorded, as the damaged progressed. Signature data was processed, and the damage index was calculated. The initiation and propagation of damage, i.e., structural crack, was successfully correlated with the E/M impedance measurements. Damage index values were observed to increase as crack damage increases. Sensing and the localization principles of E/M impedance NDE method were confirmed. Rejection of spurious information was also confirmed. Through these experiments, the E/M impedance technique has been, once again, proved to be a powerful tool with good potential for damage detection, health monitoring, and NDE.
Active Control of Crane-Load Vibrations on Ship Vessels
Authors: Li Y.-Y. , Balachandran B. 
Published: January 2022

Abstract
In order to suppress crane load vibrations on ship vessels, a novel mechanism called a mechanical filter was developed by us recently. This mechanism was implemented on the basis of the premise that by actively and passively controlling the pivot point about which the load oscillates, one can effectively suppress crane load motions. In the present efforts, it is demonstrated that with an aid of a static feedback control law, one can effectively eliminate bifurcations that can lead to large changes in the crane load motions from the window of the considered ranges of disturbance frequency and disturbance amplitude parameters. The response amplitude of the crane load to ship-roll motions is attenuated to a low magnitude over the disturbance parameter window. Variations in the control input with respect to the crane-load mass are also investigated.
New Maintenance (Inspection) Method for Ground Machines
Authors: Egawa Koichi 
Published: January 2022

Abstract
The main purpose of this paper is to forecast maintenance (inspection) technology in the near future which will be led by the introduction of the Intelligent (smart) materials and structures (IMS) concepts into this technology. Concerning the IMS concepts, many research works have been conducted and many proposals are still being offered, but it remains as an idea or a mere concept. But, the author would like to say that it already takes practical, concrete form in some places in the technological, engineering world. As an example, the change of maintenance ways of about 120 die-casting machines in a factory is presented here. It would be thought that this change would bring about introducing IMS’s primary stage concept, sensory structure; however, even maintenance people in that factory are not conscious about what IMS concept is.
Front End Design of Aluminum Vehicle for Crashworthiness
Authors: Farooq Rehan 
Published: January 2022

Abstract
This paper discusses the methods and techniques in designing a mid-size Aluminum vehicle front end for crashworthiness. Aluminum was used in place of steel in order to reduce weight, hence the fuel consumption, this change allowed a reduction of about 53% in total weight of BIW as compared to steel one with same size and crush strength. For maximum energy absorption, concept of progressive localized buckling of vehicle components was used. To develop the most efficient energy absorbing cross-sections for front end components a computer beam code SECOLLAPSE is used. Cross sectional properties (Peak and Mean loads) of these sections were compared to the steel cross sections. Front end components then modeled and analyzed by using the non linear Finite Element crash code V-CRUSH and the final design was verified by comparing with existing steel design of similar configuration. Testing of this structure and its various front end component is under way and results will be presented in a later study.
Occupants Safety due to Mass and Stiffness of Vehicles in Head-on Collision
Authors: Jawad Saad A. W. 
Published: January 2022

Abstract
Compatibility of vehicles of different mass and stiffness in head-on collisions was studied in earlier paper(13). It was concluded that mass ratio was the most important parameter in the mechanics of head-on collision. To improve compatibility, it was also suggested that stiffness might be reduced with longer crumple zone for heavier vehicles. This paper continues the study by considering the impact of changing stiffness of a vehicle on the level of protection the vehicle provides to its own occupants when colliding with similar vehicle. Such study is prompted by the fact that there is a strong link between aggressivity of a vehicle to the partner vehicle’s occupants and the level of protection the vehicle provides to its own occupants. In other words safer vehicles are usually more aggressive. A compromise between the level of protection and aggressivity of the vehicle design need to be investigated using basic laws of mechanics of head-on collisions. An eight-degrees of freedom, two-dimensional lumped-mass simulation model was used for this purpose.
Three injury risk criteria have been considered in this study; delta V or change in velocity of vehicle after impact, maximum acceleration sustained by the passenger compartment throughout impact, and length of deformation sustained by the car front Both mass and stiffness are crucial for the occupants safety. Higher mass provides protection to its occupant as well as aggressivity to occupants of the partner vehicle. Higher stiffness provides little protection to its occupants in terms of the intrusion injury criterion but more aggressive to its own occupants as well as occupants of the partner vehicle in terms of other injury criteria. A slightly softer and longer crumple zone is proposed for heavier vehicles to achieve better protection for occupants of both colliding vehicles.
Side Airbag Design Using an Enhanced MADYMO SID Model
Authors: Deng Yih-Charng , Peng Julie , Setru Prabhu 
Published: January 2022

Abstract
In this study, we evaluated and enhanced a SID model in the MADYMO database. It was found that the original MADYMO model exhibited discrepancies with the SID responses measured from the barrier impact test. After a number of improvements were made to the thorax region the revised model showed better correlation with the test results. Design exercises were performed using the SID model to study the design of a side airbag for a large car, including the effects of different sizes for the vent, inflator and bag. Occupant responses indicated that a large vent is beneficial whereas low sensitivities were found for the inflator and bag size variations.
Application of Foam in Reducing Lower Leg Injuries
Authors: Chen Roger , Belwafa Jamel E. 
Published: January 2022

Abstract
Occupant safety has been, and always will be, one of the Auto-makers main objective and concern. For the past ten years, widespread use of airbags has reduced the risk of head and chest injuries making lower extremity injuries relatively more important. The purpose of this paper is to study the feasibility of using energy absorbing material in the toeboard area in order to reduce lower leg high axial and bending force levels. The study consists of comparing and evaluating the physical properties and dynamic impact performance characteristics of different recoverable foams. The choice of the tested foams was based on their energy absorbing potential. Although preliminary results showed benefits in using foam in the toeboard area to absorb some of the energy transferred to the occupant feet, further studies were recommended to ensure that the selection of a particular foam is best suitable for this application.
Modeling Human Brain Movability Effect on Brain Response During Impact
Authors: Hu Hao , Rosenberg William S. , Nayfeh Adnan H. 
Published: January 2022

Abstract
Brain responses due to its movability during impact was investigated by using sliding interface approach. A new 3D 50th percentile human head finite element model has been generated in which sliding interfaces totally separate the brains and cerebrospinal fluid (CSF)/cranium. So, the brains can move to some extent. It becomes an equivalent one to most widely used brain/CSF (cranium) coupled models by switching interface type from sliding to tied. The model was partially validated by using available experimental and computed data in frontal impact. Compared with brain/CSF (cranium) coupled models, the new model predicts higher brain stress levels at sites such as corpus callosum, brain stem, and the vicinity of the ventricles etc. and more realistic deformation patterns. The results suggest that a fluid-solid interaction approach should be used to better model brain movement during impact to correctly interpret the brain injuries and to evaluate proposed head injury mechanisms.
Advanced Material Distribution Measurement in Multiphase Flows: A Case Study
Authors: George D. L. , Ceccio S. L. , O’Hern T. J. , Shollenberger K. A. , Torczynski J. R. 
Published: January 2022

Abstract
A variety of tomographic techniques that have been applied to multiphase flows are described. The methods discussed include electrical impedance tomography (EIT), magnetic resonance imaging (MRI), positron emission tomography (PET), gamma-densitometry tomography (GDT), radiative particle tracking (RDT), X-ray imaging, and acoustic tomography. Also presented is a case study in which measurements were made with EIT and GDT in two-phase flows. Both solid-liquid and gas-liquid flows were examined. EIT and GDT were applied independently to predict mean and spatially resolved phase volume fractions. The results from the two systems compared well.
Three-Dimensional Tomography Methods in Flow Visualization
Authors: Pickalov Valery V. 
Published: January 2022

Abstract
The paper gives a review of modern optical tomography techniques, and corresponding two- and three-dimensional algorithms are also discussed. Special emphasis is laid on the synthesis of tomography approaches with the new image processing technique.
Some examples of the new methods of tomography for incomplete data, local tomography of high gradient structures are discussed. The role of Vainberg image for three-dimensional object visualization is shown.
Scalability Studies on a cc-NUMA Computer Architecture for Large Automotive Simulations
Authors: Hytopoulos Evangelos , Kremenetsky Mark D. , Andra Ramesh , Sun Richard , Posey Stan 
Published: January 2022

Abstract
The maturity of the Computational Fluid Dynamics methods and the increasing computational power of today’s computers have allowed the automotive industry to incorporate the CFD technology in several stages of the design process. As the application of the CFD technology is moving from the component level analysis to the system level, the complexity and the size of the models increase continuously. Successful simulation requires synergy between CAD, grid generation, and solvers.
The requirement for shorter design cycle has put severe limitations on the turnaround time of the numerical simulations. The time required for a) mesh generation (around bodies of complex geometry, such as the geometry of a complete car), and b) obtaining numerical solutions (for flows with complex physics) has traditionally been the pacing item in CFD applications. Unstructured grid generation techniques and parallel algorithms have been instrumental in making such calculations affordable. Availability of these algorithms in commercial packages has proliferated in the last few years and parallel performance has become a very important factor in the selection of such methods for production work.
Although extensive research has been devoted in determining the optimum parallel paradigm, in practice the best parallel performance can be obtained only when the algorithms and paradigms take into consideration the architectural design of the target computer that they are intended for. The present paper addresses the issues related to the porting and optimization of a commercial code (Fluent/UNS) on a cache-coherent (cc) Non Uniform Memory Architecture (NUMA). Issues related to the Message Passing system and the memory to processor affinity are investigated using both a sample CFD code and Fluent/UNS. The scalability of the code when applied to the problem of the front-end cooling simulation of a development prototype family sedan are presented and discussed. Since speed and accuracy are the ultimate goals for using CAE in the design process a discussion concerning the model preparation time, grid generation process, and solution time will be presented. Comparison with available experimental data will be presented and discussed.
Fluid Transient in a Voided System
Authors: Niyogi Kalyan K. , Burdett Robert R. , Unikewicz Steven 
Published: January 2022

Abstract
The phenomenon of void formation in a piping system due to heat transfer and subsequent collapse due to pump start has been explored. The analysis is based on a computer model developed for the RELAP5 computer program [Ref. 1] and is applied to a cooling water system in a nuclear plant. This evaluation has been performed to respond to a generic concern in the industry. The concern arises from the fact that if the cooling water pump fails and there is significant heat transfer from the process side into the system, there is a potential for void formation in the system. Subsequently, as the pump restarts the void collapses due to pressurization and condensation, and consequently, may result in significant pressure surges.
It has been observed that for a closed system the pressure surges are greatly influenced by the presence of a surge tank connected at the pump suction piping. During the initial period of the restart of the pump the fluid is drawn from the surge tank at a greater proportion until the fluid in the main line is accelerated to a steady state value at which time the flow in the surge line ceases. The relative speeds of the two fluid fronts, one approaching to the void and another departing from the void, at the time of the complete collapse determine the surge pressure.
Factors affecting the surge pressure include the resistance in the surge line, the size of the void and the quality of contained steam, temperature of water surrounding the void, and the amount of non-condensable present in water. The forces calculated for the piping segments could be significant compared to other loads on the supports.
The most effective ways of reducing excessive pressure surges include pressurization and/or increasing the elevation head of the surge tank and increasing the surge line resistance by installing an orifice or throttling of an existing valve.
Column Separation in Inclined Pipes
Authors: Husaini Syed M. , Arastu Asif H. 
Published: January 2022

Abstract
The most commonly used models (based on the Method of Characteristics numerical scheme) for column separation in liquid pipes assume that the vapor pocket occupies the whole cross sectional area of the pipe. Beyond the right and the left boundaries of the vapor pocket the pipe cross sectional area is full of liquid. However, under certain conditions, depending on the pipe gradient, flow rate, etc., the piping downstream of the high elevation point may have flow that only occupies a portion of the pipe cross section. The empty region of the pipe will consist of vapor formed due to the flashing of the liquid. The conventional methodology used for the analysis of column separation cannot be applied under such conditions. A MOC based calculation scheme is developed, which treats the partially filled regions of the piping system as open channel flow. It is generalized to allow for transition from partially full to full flow conditions, and vice-versa. This methodology has been incorporated into the computer program HSTA (Hydraulic Systems Transient Analysis) and the advantages/limitations of the various methodologies are compared.