bluuebunny/crossref_metadata_2025_split huggingface dataset:
A One-Dimensional Approach to Viscoelastic Material Stiffness Calculations
Authors: Mayrose James , Kesavadas T. , Narayanasamy Senthil K. 
Published: December 2021

Abstract
Accurate models of human body tissues and organs have tremendous applications in the medical field. Modeled organs within virtual environments are increasingly being used as research tools in medicine. In the near future, these research tools will make their way into teaching and clinical practice. These virtual environment simulations allow researchers to study the behavior of human organs and to develop large databases of organ characteristics. The 3D viewing and interaction available through virtual reality make it possible for physicians to practice many medical procedures without ever touching a patient. The main goal of this study is to evaluate the effectiveness of a “sensory data glove”, developed by the authors, for calculating the stiffness of an object beneath a surface of varying stiffness.
The Annual National Science Foundation Publication on Senior Design Projects to Aid Persons With Disabilities
Authors: Enderle John D. 
Published: December 2021

Abstract
An annual publication on senior design projects to aid persons with disabilities supported by the National Science Foundation since 1988 is described in this report Some of the projects described in these books are custom modifications of existing devices, modifications that would be prohibitively expensive to the disabled individual were it not for the student engineer and this NSF program. Other projects are unique one-of-a kind devices wholly designed and constructed by the student for the disabled individual. Some projects built in years past include a laser-pointing device for people who cannot use their hands, a speech aid, a behavior modification device, a hands-free automatic answering and hang-up telephone system, and an infrared beacon to help a blind person move around a room.
Dynamic Modeling and Controller Design for a Piezoelectric Actuation System Used for Machine Tool Control
Authors: Mayhan Paul , Srinivasan K. , Watechagit Sarawoot , Washington G. 
Published: December 2021

Abstract
The dynamic model of a commercially available piezoelectric actuation system intended for use in a machine tool position control system is presented, and its fidelity to observed behavior evaluated. The components of the actuation system are presented and an available nonlinear dynamic model form for piezoelectric actuators, capable of representing actuator hysteresis, used as the basis for the system dynamic model. Parameters in the dynamic model are obtained from manufacturer’s specifications. The resulting actuator model is combined with a nonlinear model of the amplifier, the resulting system model forming the basis of a SIMULINK simulation. System responses based on the simulation are compared with experimentally measured responses. The agreement between simulation and experimental responses is reasonably good at low frequencies, and the model is used for preliminary closed loop position control system evaluations. Specific recommendations for improvement in model accuracy are also made.
Improved Output Active Vibration Control Using Large Aperture Strain Transducers
Authors: Vipperman Jeffrey S. 
Published: December 2021

Abstract
An experimental study is conducted to illustrate the advantages of increasing the aperture size of strain transducers used to perform direct rate feedback (DRFB) control. Twelve individual piezoceramic patches are installed to form a contiguous 3 × 4 array on a simply supported plate structure. The patches are grouped to form four different sized apertures consisting of 1, 4, 8, or 12 individual patches. The open loop results for all four cases show increased coupling into the low frequency modes of the plate as well as more uniform compliance in the frequency response function. As a result, much improved direct rate feedback control performance is achieved.
The Use of Microencapsulated Phase-Change Materials to Enhance the Thermal Performance of Apparel
Authors: Holman Mark E. 
Published: December 2021

Abstract
Recent advancements in the apparel industry have generated increasing interest in phase-change materials (PCMs), due largely to the advantages of microencapsulation. Microencapsulated phase change materials (microPCMs) provide latent heat benefits nearly equal to those of bulk PCMs, yet the PCM remains contained within a shell when melted. As such, microPCMs can be incorporated into a wide variety of products to greatly improve thermal management.
MicroPCMs can be incorporated into both solid and liquid carriers. They can increase the thermal capacitance of solids as much as 10 times, while the effective heat capacities of fluid-based microPCM systems have been shown to increase as much as 40 times (Mulligan et al., 1996).
Extensive microPCM research by Triangle Research and Development Corporation, among others, has ultimately led to the creation of numerous thermally enhanced apparel products. As the capabilities of microPCMs become more widely known, the number and variety of microPCM-based apparel and footwear products continue to grow.
Mechanical Strength Modeling of Particle Strengthened Nickel-Aluminum Alloys Strengthened by Intermetallic γ′ (Ni3Al) Precipitates
Authors: Fragomeni James M. 
Published: December 2021

Abstract
A Nickel-Aluminum alloy strengthened by γ′ (Ni3Al) intermetallic ordered coherent precipitates with a small misfit strain was used a demonstration material to develop a model to predict strengthening behavior during plastic deformation as a consequence of the γ′ particles acting as obstacles to the dislocations and thus impeding their glide motion through the alloy. It was determined that the two most dominate strengthening mechanisms in the Ni-Al system were order hardening when the particles were smaller than the critical looping radius, and Orowan strengthening when the particles were larger than the looping radius. In the overaged condition when the particles are large in size, the dislocations bypass and loop the particles by the Orowan mechanism. In the underaged to peak aged conditions where the particles are usually smaller than the looping radius, the dislocations shear the precipitates during deformation. The total polycrystalline yield strength included contributions from the intrinsic lattice strength, the solid solution strengthening, grain size strengthening, and particle strengthening which included the order hardening and Orowan strengthening contributions. The total mechanical yield strength for a Ni-6.27wt.%A1 alloy was predicted for the peak-aged condition based on the theory for order strengthening and was found to be in good agreement with the experimental peak-strength data for Ni-6.27A1.
Statistics and Quality Management in Manufacturing in a High School Setting
Authors: Dimmer Maureen E. , Pierno Michael C. 
Published: December 2021

Abstract
By incorporating Statistical Process Control (SPC), this high school probability and statistics course provides an answer to the eternal question of students, “How are we ever going to use this?” Students learn the traditional introductory theoretical probability and descriptive statistics and also experience the real-world application, SPC, by doing two manufacturing projects in conjunction with the engineering technology students. The initial project, manufacturing precision 3-D puzzle pieces, offers a straightforward example of the necessity of stringent quality control. Later in the semester, students construct a 50-link chain of identical plastic links, each of which must pass several rigorous quality checks to enable all the pieces to interlock successfully.
The head of the engineering technology department and a mathematics teacher designed the course to better prepare their students for the world of work in the 21st century. Local business people contributed to the design of the course and teach some sessions.
Teaching Mechatronics to the New Generation
Authors: Hayward Gregory P. , Furman Burford J. 
Published: December 2021

Abstract
Students entering undergraduate programs have increasing familiarity with elements of mechatronics such as computer programming skills and familiarity with robotics. A new elective course in mechatronics at San José State University is under development through collaboration of senior mechanical engineering students and faculty to effectively teach mechatronics to the new generation of students. The proposed course is project-based and uses a self-contained microcontroller so that students can work on their project outside of a traditional laboratory space.
Finite Element Analysis of Transient Thermal Problems of Work Rolls in Hot Rolling Process
Authors: Lee James D. , Manzari Majid T. , Shen Yin-Lin , Zeng Wenjun 
Published: December 2021

Abstract
The three-dimensional transient thermal problem of work rolls in the entire hot rolling process has been formulated. It includes the time-varying boundary conditions specified at the roll surface taking the schedule of both rolling and idling cycles into consideration. The corresponding finite element equations are derived and solved by the Runge-Kutta-Verner method. The finite element solutions indicate that the temperature variations in the circumferential direction are overwhelming. Case studies unveil the thermal characteristics of the work rolls in various kinds of mill operations. Numerical results are presented and compared with Guo’s analytical solutions.
Solid Freeform Fabrication by GMA Welding: Geometry Modeling, Adaptation and Control
Authors: Kwak Yong-Min , Doumanidis Charalabos 
Published: December 2021

Abstract
This paper introduces the Gas Metal Arc Welding process with deposition shape control to solid freeform fabrication for large sculpted metal objects and rapid tooling of molds and dies. Besides full density and toughness properties, GMAW deposition must ensure near-net-shape surface geometry. To this end, an analytical model of deposited morphology is derived, based on linearized superposition of ellipsoidal unit deposition globules. The time-varying parameters of these primitives are identified in-process using laser scanning measurements of the bead width. An experimental description of width on the GMAW inputs is also established. On this basis, bead width control through the wire feed is implemented in real time, using Smith prediction to cope with sensor delays, and feedforward to compensate for the predeposited terrain. This controller was validated in the laboratory, in stainless steel deposition in single and overlaid beads.
Modeling the Temperature/Force Phenomena of an Extra-Low Carbon Steel in Two-Phase Hot Rolling
Authors: Hwu Yhu-Jen , Wu Chang-Huei 
Published: December 2021

Abstract
Extra-low carbon steel had been rolled in conventional hot rolling mill. For improving its mechanical and metallurgical properties, its high phase transformation temperature typically encountered in the finishing mill section that results in abrupt change of flow stress and consequently the rolling force. A simple temperature/force model is proposed to predict the strip temperature and mill loading force to achieve better understanding of complicated phenomena encountered in the field and also for future initial rolling condition setup. Preliminary results based on the model are satisfactorily close to the on-line rolling data from the seven-stand mill of China Steel Corporation.
Industrial Design to Rapid Mold Making for Accelerated Time-to-Market of Consumer Electronic Products
Authors: Wang Fu-Chung , Plancarte Juan , Wright Paul K. , Fabbrizio Vito , Kramer Alan 
Published: December 2021

Abstract
The demand for quick time-to-market and the short product life cycle of consumer electronics are now pushing the development time for these products even shorter. The success of a rapid product development requires careful considerations of product markets, production needs, and available design and fabrication resources at the early development stage, and a seamlessly integrated design to fabrication environment for rapid product realization. In this paper, through a case study on the prototyping production of a finger-print recognition device, we illustrate a rapid product development through an integrated CAD/CAM environment. Rapid production of an accurate aluminum mold for 200 prototypes is highlighted. The result was a product prototype delivered within a short period of development time according to the proposed schedule. Time analysis of the entire development process was provided, and some potential improvements based on the analysis were also identified for future development of similar products.
Influence of Kinematic Characteristics on Grinding Ultra-Precision Substrates
Authors: Tso Pei-Lum , Teng Chieng-Chung 
Published: December 2021

Abstract
This study concerns with the kinematic characteristics of grinding ultra-precision substrate with the rotary-table vertical-spindle surface grinder. The relative position, velocity, acceleration of single grain on cup-wheel traveling along the substrate have been calculated and studied. Factors affecting the flatness of the ground substrate may be considered as: the non-uniformity of relative velocity, the non-uniformity of relative acceleration, the passing ratio of center to periphery of the substrate, the mean thickness of undeformed chip. These are influenced considerably by the value of the rotational speed ratio of cup-wheel and worktable as well as the wheel infeed rate. The experimental study indicated that the passing ratio is the main factor and the inclination of grinding wheel axis must be appropriately performed to improve the flatness of ground substrate.
Grit Interaction Model for Rotary Disc Truing of CBN Grinding Wheels
Authors: Prusak Zbigniew , Webster John A. 
Published: December 2021

Abstract
Performance of a grinding operation depends mainly on material removal ability of the grinding wheel used, which is closely related to its cutting sharpness. In the case of CBN wheels, the cutting sharpness can be traced to the interaction between CBN and diamond grits during truing process. This paper presents a mathematical model for predicting the number of collisions that a CBN grit is subjected to in truing process when various designs of truing disc are used. The model takes into account geometric and kinematic characteristics of wheel-truer engagement, and interaction between colliding grits. Various characteristics of truer, wheel and truing process are also included. Grit retention parameter z, which was introduced in this research, accounts for the capability of retaining grits in truer and wheel. Modelling results are compared to results from truing and grinding tests.
Precision Sensing of Arc Length in GTAW Based on Arc Light Spectrum
Authors: Li P. J. , Zhang Y. M. 
Published: December 2021

Abstract
This work aims at improving the measurement accuracy of arc length using the spectrum of arc light at a particular wavelength during gas tungsten arc welding with argon shield. To this end, effects of welding parameters on spectral distributions were studied. To verify the effects of base metal and arc length, the arc column was also sampled horizontally as layers for spectral analysis. Results showed that spectral lines of argon atoms are determined by arc length and independent of welding parameters other than the arc length. Based on these findings, a compact arc light sensor has been designed to measure the arc length with an adequate accuracy. A closed-loop arc length control system has been developed with the proposed sensor.
Research on Digital Control of Meter-In and Meter-Out Independent Regulating for High Inertia Load
Authors: Wang Qingfeng , Gu Linyi , Lu Yongxiang 
Published: December 2021

Abstract
The smoothness of acceleration and deceleration process is a serious problem in valve control system with high inertia load, especially in the hydraulic systems in construction machines.
In this paper, a meter-in and meter-out independent regulating method, in which the two sides of actuator are controlled by a meter-in valve and a meter-out valve respectively, is put forward, in one hand, the meter-out valve could control the actuator’s outlet pressure to avoid the ultra-high outlet pressure when actuator decelerates or brakes suddenly. On the other hand, the dynamic damping ratio of valve control system could be raised through calculated flow feedback control algorithm.
Secondly, a grading control algorithm in dynamic process of high inertia load is adopted. When the actuator’s velocity is far from its command value, the actuator’s inlet and outlet pressure are controlled. After the velocity error decrease to a threshold, a state feedback control algorithm based on parameters on line estimating is employed to realize both its velocity accuracy and the smoothness of dynamic process.
Experiments show that the actuator’s velocity could increase or decrease to its command value accurately, smoothly and rapidly after the above method and algorithm are applied.
A Novel Thin Film Solid Oxide Fuel Cell for Microscale Energy Conversion
Authors: Morse Jeffrey D. , Jankowski Alan F. , Hayes Jeffrey P. , Graff Robert T. 
Published: December 2021

Abstract
A novel approach for the fabrication and assembly of a solid oxide fuel cell system is described which enables effective scaling of the fuel delivery, manifold, and fuel cell stack components for applications in miniature and microscale energy conversion. Scaling towards miniaturization is accomplished by utilizing thin film deposition combined with novel micromachining approaches which allow manifold channels and fuel delivery system to be formed within the substrate which the thin film fuel cell stack is fabricated on, thereby circumventing the need for bulky manifold components which are not directly scalable. Results demonstrating the generation of electrical current in the temperature range of 200–400°C for a thin film solid oxide fuel cell stack fabricated on a silicon wafer will be presented.
Three-Dimensional Graphic Analysis of Absorption Cycles
Authors: Shelton Sam V. , Vodenicker John P. , Schaefer Laura A. 
Published: December 2021

Abstract
Due to new computer software tools and high speed personal computers, it is now possible to quickly analyze and optimize complex absorption heat pump cycles. These cycles utilize fluid mixtures and can have a large number of components. Absorption cycles are typically displayed on two-dimensional graphs, but these diagrams can cause confusion in understanding new cycle configurations and their potentials and limitations. This study uses three-dimensional graphs to create accurate representations of four cycles. In the advanced cycles, the many opportunities for internal heat recovery can be clearly seen. Additionally, the three-dimensional representations can justify the inclusion or removal of cycle components. They are an excellent tool for those new to the field to more quickly understand the cycles, and for those experienced with absorption to be innovative in developing new cycles.
A Role for Exergy Analysis and Optimization in Aircraft Energy-System Design
Authors: Bejan Adrian 
Published: December 2021

Abstract
This paper outlines a newly emerging body of work that relies on exergy analysis and thermodynamic optimization in the design of energy systems for modern aircraft. Exergy analysis establishes the theoretical performance limit. The minimization of exergy destruction brings the design as closely as permissible to the theoretical limit The system architecture springs out of this constrained optimization principle. A key problem is the extraction of maximum exergy from a hot gaseous stream that is gradually cooled and eventually discharged into the ambient. The optimal configuration consists of a heat transfer surface with a temperature that decays exponentially in the flow direction. This configuration can be achieved in a counterflow heat exchanger with an optimal imbalance of flow capacity rates. The same optimal configuration emerges when the surface is minimized subject to specified exergy extraction rate. Similar opportunities for optimally matching components and streams exist in considerably more complex systems for power and refrigeration. They deserve to be pursued, and can be approached first at the conceptual level, based on exergy analysis and thermodynamic optimization. The application of such principles in aircraft energy system design also sheds light on the design principle that generated all the systems that use powered flight, engineered and natural.
Constitutive Modeling for Impact Simulation of Random Fiber Composite Structures
Authors: Lee Haeng-Ki , Simunovic Srdan 
Published: December 2021

Abstract
A constitutive model for progressive crushing is presented to predict impact behavior and damage evolution in random carbon fiber polymer matrix composites (RCFPMCs). Based on the ensemble-volume averaging process and first-order effects of eigenstrains due to the existence of prolate fibers, an effective yield criterion is derived to estimate the overall elastoplastic damage responses. First, an effective elastoplastic constitutive damage model for aligned fiber-reinforced composites is proposed. A micromechanical damage constitutive model for RCFPMCs is then developed. The governing field equations and overall yield function for aligned fiber-orientations are averaged over all orientations to obtain the constitutive relations and effective yield function of RCFPMCs. Finally, the complete progressive damage constitutive model is implemented into finite element code DYNA3D to solve large scale problems such as automobile components and systems. An advantage of the progressive damage analysis is that the information from the progressive damage model can be implemented into finite element code as material input properties and thus the calculations required in the constitutive model can be greatly reduced.
Integrated Transient Thermal and Mechanical Analysis of Molded PBGA Packages During Thermal Shock
Authors: Mercado Lei L. , Lee Tien-Yu Tom , Cook Jeff 
Published: December 2021

Abstract
During thermal shock, large thermal gradients exist within a molded plastic ball grid array (PBGA) package. The conventional assumption of uniform temperature distribution becomes invalid. In this paper, an integrated thermal-mechanical analysis was performed to evaluate the transient effect of thermal shock. For comparison, an isothermal analysis was also conducted. The computational fluid dynamics (CFD) method was used to obtain the thermal boundary conditions surrounding the package. The heat transfer coefficient obtained through CFD was compared to two analytical solutions. It was found that the analytical values were not acceptable in the time period of interest. Therefore, to obtain the actual maximum die stress, CFD solution has to be used instead of analytical solutions to derive the thermal boundary condition. This boundary condition was then applied to the package and a sequentially coupled heat transfer and thermal stress analysis was performed. The transient analysis has shown that high stresses occur in the die due to thermal shock, which can not be seen under the traditional isothermal assumption. The impact of PBGA package parameters on transient die stress was also studied, including mold thickness and substrate thickness. The results in this paper could be applied to either wire bond or flip-chip PBGA packages.