bluuebunny/crossref_metadata_2025 huggingface dataset:
A Qualitative Approach to Studying the Interplay Between Expertise, Creativity, and Learning in University Makerspaces
Authors: Tomko Megan , Nagel Robert L. , Linsey Julie , Aleman Melissa
Published: November 2017

While students make in makerspaces, they traverse and integrate a variety of skills that create a dynamic relationship between learning processes, creative exploration, and expertise acquisition. We put forth that in order to certify and reveal the value of making, it is necessary to investigate this interplay between learning, creativity, and expertise using qualitative methods. This paper presents a comprehensive literature review and research initiative that demonstrate how to utilize ethnographic approaches to study learning in makerspaces. Specifically, we present initial steps to explore this dynamic relationship with the goal of answering the question What do students learn in universities makerspaces? At present, it is unclear what university students actually learn in university makerspaces, and how learning in makerspaces compares to learning in other hands-on learning opportunities such as competition team projects (e.g., SAE), undergraduate research, or other informal engineering learning environments. This research initiative focuses on two very different makerspaces at two different universities, which creates a unique opportunity for comparison. To study these spaces, we implement observation, participant observation, and interviewing of students, particularly on making. We envision this work as a springboard for further work in understanding makerspaces.
Parametric Design and Optimization of the Impeller Geometry for an Automotive Torque Converter Using DOE Method
Authors: Wu Guangqiang , Chen Jie
Published: November 2017

Design of experiment (DOE) and computational fluid dynamics (CFD) techniques are applied to obtain an optimal design of the impeller geometry for an automotive torque converter. A new parametric geometric design method of impeller is proposed by means of parametric equations and Creo software. Eleven design parameters are used to obtain the parametric model and can be represented by six parameters including impeller blade number, blade thickness, bias angle, scroll angle, inlet angle and exit angle. DOE method is used to investigate the relative importance of the six design parameters for each response (stall torque ratio and peak efficiency). The impeller bias angle is found to exert the greatest influence on stall torque ratio while the impeller exit angle has the strongest impact on the peak efficiency. Three optimized cases for the impeller geometry of an automotive torque converter are obtained based on desirability function approach. The new parametric design and optimization methods can provide fundamental guidelines for performance enhancement in the design process of impeller geometry for an automotive torque converter.
Modular Elastic Lattice Platform for Rapid Prototyping of Tensegrity Robots
Authors: Chen Lee-Huang , Daly Mallory C. , Sabelhaus Andrew P. , Janse van Vuuren Lara A. , Garnier Hunter J. , Verdugo Mariana I. , Tang Ellande , Spangenberg Carielle U. , Ghahani Faraz , Agogino Alice M. , Agogino Adrian K.
Published: November 2017

This paper presents a new platform for prototyping tensegrity robots that uses an elastic lattice structure for the robots’ tension network. This approach significantly reduces the time required for design, manufacturing, and assembly, while increasing experimental repeatability and symmetry of the tensioned robot. The platform allows more scientific experiments to be performed in less time and with higher quality.

This lattice platform, with associated laser-cutting design techniques developed in this work, has been applied to three types of tensegrity structures: 6-bar spheres, 12-bar spheres, and multiple-vertebra tensegrity spines. For the 12-bar tensegrity case in particular, this new lattice platform has allowed multiple different shapes to be explored as designs for future robots. Basic testing confirmed a reduction in robot assembly time from multiple hours down to a mean of one-two minutes for the 6-bar prototype, five-ten minutes for the various 12-bar prototypes, and approximately seven minutes for the spine.
A Manufacturing Oriented Single Point Search Hyper-Heuristic Scheme for Multi-Objective Optimization
Authors: Cao Pei , Fan Zhaoyan , Gao Robert , Tang Jiong
Published: November 2017

Multi-objective optimization problems are frequently encountered in engineering analyses. Optimization techniques in practical applications are devised and evaluated mostly for specific problems, and thus may not be generally applicable when applications vary. In this study we formulate a probability matching based hyper-heuristic scheme, then propose four low-level heuristics which can work coherently with the single point search algorithm MOSA/R (Multi-Objective Simulated Annealing Algorithm based on Re-pick) towards multi-objective optimization problems of various properties, namely DTLZ and UF test instances. Making use of the domination amount, crowding distance and hypervolume calculations, the hyper-heuristic scheme could meet different optimization requirements. The approach developed (MOSA/R-HH) exhibits better and more robust performance compared to AMOSA, NSGA-II and MOEA/D as illustrated in the numerical tests. The outcome of this research may potentially benefit various design and manufacturing practices.
Design of a Spatial Six-Bar Flapping Wing Mechanism for Combined Control of Swing and Pitch
Authors: Wang Peter L. , McCarthy J. Michael
Published: November 2017

This paper presents a design procedure to achieve a flapping wing mechanism for a micro air vehicle that drives both the swing and pitch movement of the wing with one actuator. The mechanism combines a planar four bar linkage with a spatial RSSR attached to the input and output links forming a spatial Stephenson six-bar linkage. Function generation synthesis yields a planar four-bar that controls the wing swing profile. The pitch control is synthesized by inverting the movement of the combined system to isolate and compute the SS chain. In order to ensure the design achieves the specified task precision points, the SS chain was randomized within a prescribed tolerance zone. The result was 29 designs, one of which is presented in detail.
On the Origin of the Nonclassical Softening Nonlinearity in MEMS/NEMS Cantilevers
Authors: Tan David , Erturk Alper
Published: November 2017

Cantilevered configurations of thin beams are used in numerous conventional and emerging applications of mechanical, aerospace, and civil engineering, as well as material science. In many resonant scenarios, nonlinearities are inevitably pronounced under moderate to large intensity excitations. Other than dissipative nonlinearities due to internal and external damping mechanisms, and in the absence of material nonlinearities such as those of piezoelectricity, two types of nonlinearities are pronounced for large amplitude dynamics of Euler-Bernoulli cantilevers in the first bending mode: stiffness hardening due to nonlinear curvature and inertial softening. While these two counteracting nonlinearities are both of cubic order, it can be shown theoretically that the geometric hardening always dominates inertial softening for the response of the first bending mode, and therefore one does not expect softening in the resulting dynamics. Most of the existing experiments in conventional structures are aligned with this theoretical expectation. Recent efforts in NEMS cantilevers resulted in experimental data with a softening nonlinearity instead of the classical overall hardening for the first bending mode. The perplexing results made some authors suggest that the Euler-Bernoulli theory was not sufficient to capture the resulting dynamics, and that a new theory would be required. In the present work, we hypothesize that the observed softening effect in the fundamental resonance may be a result of the asymmetric boundary condition of the NEMS cantilever (due to its fabrication) at the clamped end such that the cantilever experiences two different boundary conditions in the two halves of the oscillation cycle. We show both theoretically and experimentally that such uneven boundary conditions indeed result in softening behavior in the first bending mode, while the evenly clamped case yields the expected hardening.
Modular Design of a Passive, Low-Cost Prosthetic Knee Mechanism to Enable Able-Bodied Kinematics for Users With Transfemoral Amputation
Authors: Berringer Molly A. , Boehmcke Paige J. , Fischman Jason Z. , Huang Athena Y. , Joh Youngjun , Warner J. Cali , Arelekatti V. N. Murthy , Major Matthew J. , Winter Amos G.
Published: November 2017

There is a significant need for low-cost, high-performance prosthetic knee technology for transfemoral amputees in India. Replicating able-bodied gait in amputees is biomechanically necessary to reduce the metabolic cost, and it is equally important to mitigate the socio-economic discrimination faced by amputees in developing countries due to their conspicuous gait deviations. This paper improves upon a previous study of a fully passive knee mechanism, addressing the issues identified in its user testing in India. This paper presents the design, analysis and bench-level testing of the three major functional modules of the new prosthetic knee architecture: (i) a four-bar latch mechanism for achieving stability during stance phase of walking, (ii) an early stance flexion module designed by implementing a fully adjustable mechanism, and (iii) a hydraulic rotary damping system for achieving smooth and reliable swing-phase control.
Prototyping Methods for a Small-to-Medium Manufacturing Enterprise in a Resource-Constrained Setting: A Case Study
Authors: Chou Suzanne , Austin-Breneman Jesse
Published: November 2017

Prototyping is an important part of the product development process, especially for the design of the manufacturing systems in small-to-medium enterprises (SMEs). Practitioners in resource-constrained settings face unique challenges when prototyping in these contexts. This work examines the methods, constraints, and impacts on design outcome of prototypes in manufacturing SMEs in resource-constrained settings through a case study. Observations and information were gathered through a site visit and interviews with the engineers at the partner organization. One of the important findings of this case study is that the main intent of prototyping is to develop high-fidelity, functional prototypes through simple prototyping, iteration, and the emphasis on physical prototypes. The overarching resource constraints on achieving this prototyping intent were found to be a variance in prototyping inputs, limited access to appropriate manufacturing capabilities, and limitations of modeling predictions.
A Methodology to Quantify Cumulative Damage Function (CuDF) for Integration Into an Object-Oriented Life Cycle Assessment (LCA)
Authors: Deo Devdatta , Esterman Marcos , Thorn Brian K.
Published: November 2017

Life Cycle Assessment (LCA) is one of the most widely used tools to determine environmental impact of products and processes. One of the main concerns with the life cycle assessment tool is the limited comparability of LCA results due to limitations in defining the functional unit. In response to this, an object-oriented approach has been proposed and further developed by related research. This object-oriented approach relies on the calculation of a Cumulative Damage Function (CuDF) to quantify the amount of consumed life in each item in the bill of materials used in an LCA. The focus of this work is to develop a framework to quantify CuDF that leverages exiting reliability and life estimation methods, namely the concepts of Remaining Useful Life (RUL) and Failure Modes and Effects Analysis (FMEA). The framework is applied to a simple example to motivate its use and utility.
Conjugation Curvature Theory of Higher Pairs
Authors: Ting Kwun-Lon , Yu Zhiyuan
Published: November 2017

The paper pioneers the higher order conjugation theory that elevates the current Camus and Litvin based conjugation theory to a new level by offering the methodology to enable explicitly selecting conjugate pairs to meet the prescribed intrinsic contact characteristics or performance for contact strength. A conjugation theorem is proposed, in which a three-body conjugation system is characterized by the coinciding instant centers and from which the theory is established. Instantaneous invariants are introduced to characterize the instantaneous motion of a three-body conjugation system. The loci of points that generate conjugate pairs with the common relative curvature as well as first and second order stationary relative curvature are presented. These curvature properties determine the contact pattern and therefore the contact strength.

An immediate and important application is on gear tooth profile synthesis. The proposed theory offers the design freedom that breaks the traditional constraint of using a specific curve, such as involute. It therefore fills a void in gear tooth profile synthesis and brings light to the question on seeking the strongest tooth profiles. On the other hand, this is the first kinematic synthesis theory that generate both elements of a higher pair simultaneously for a prescribed contact performance. It is a contrast to the conventional Burmester theory by using RR, PR, or RP dyads to form a linkage.
Soft Robotic Rehabilitation Exoskeleton (REHAB Glove) for Hand Therapy
Authors: Haghshenas-Jaryani Mahdi , Nothnagle Caleb , Patterson Rita M. , Bugnariu Nicoleta , Wijesundara Muthu B. J.
Published: November 2017

This paper presents the design, control, and validation of a soft robotic exoskeleton system, the REHAB Glove, for hand rehabilitation. The system is comprised of five hybrid soft-and-rigid robotic digits that apply controlled flexion and extension motion to fingers. The previous actuator design of the soft robotic digit was improved for kinematic compatibility with anatomical motions of the hand in relation to range of motion, center of rotation, and dorsal skin lengthening. The design was validated using motion capture and analysis. A position control algorithm, which controls finger angular trajectories (angular position and velocity), was developed based on motion sensor feedback. The operation of this algorithm was verified using a 90° digit tip trajectory with two angular velocities of 15°/sec and 30°/sec. A pilot study was carried out with five healthy individuals to evaluate the performance of the REHAB Glove in providing therapeutic schemes. The results show that the REHAB Glove is able to provide controlled motion compatible with the kinematics and dynamics of the human.
Product Based Sequence Evaluation for Automated Assembly Planning
Authors: Huang Weifeng , Rafibakhsh Nima , Campbell Matthew I. , Hoyle Christopher
Published: November 2017

Assembly time estimation is a key factor in evaluating the performance of the assembly process. The overall goal of this research is to develop a method to automatically estimate product assembly time based on the tessellated model. This paper proposes a way to divide an assembly operation into four actions which consist of a) part movement, b) part installation, c) secure operations, and d) subassembly rotations. Four predictive models are built for estimating these action times with the input features that can be obtained from the tessellated model automatically. In order to estimate the four operation times, a design of experiments is applied to collect experimental data, based on the physical assembly experiments performed on products that are representative of common assembly processes. The Box-Behnken design (BBD) is an experiment design to support response surface methodology to interpret and estimate a prediction model for the four operations. With the experimental data, a stepwise regression method is used to estimate the predictive mean time. After that, a Gaussian Process (GP) model is applied with the basis mean regression function for more accurate prediction. Also, the confidence of the prediction can be given by the GP predictive confidence interval (CI). Hence, the uncertainty of the prediction can be quantified by the designer and can be used for evaluating the risk of an assembly sequence design. An Artificial Neural Network (ANN) is also used in this study to compare with the regression and GP model. A case study of a pump assembly time estimation is conducted. The predictive times from the regression, GP and ANN models are compared with the Design for assembly (DFA) method to ensure the reasonable predictions. The results show our proposed method has good prediction for most of the assembly tasks. Although errors exist in some of the task, the accuracy of the models can be improved with more user feedback since the model quality depends upon the amount of the training data.
Implementation of an Object-Oriented Life Cycle Assessment Framework Using Functional Analysis and Systems Engineering Principles
Authors: Gadre Shantanu , Esterman Marcos , Thorn Brian K.
Published: November 2017

Given that a significant percentage of a product’s impacts are defined during design and development, there is a need to effectively integrate Life Cycle Assessment (LCA) into these early phases. However, the lack of standardized practices, the lack of appropriate modeling approaches, data issues, special training requirements for designers, and uncertainties in the results make it difficult to apply LCA in these early stages. In order to address this gap, this work builds on previous research that integrated system engineering and functional analysis into LCA to develop an object-oriented framework for LCA. The framework is applied to a consumer product and the results of the approach demonstrate the potential for an easy to update and scalable LCA model that facilitates comparability. Each module in this model can be developed separately and integrated effectively into a larger model guided by functional analysis techniques. This framework holds the promise to better integrate LCA into the design and development phases.
Mining for Creativity: Determining the Creativity of Ideas Through Data Mining Techniques
Authors: Toh Christine A. , Starkey Elizabeth M. , Tucker Conrad S. , Miller Scarlett R.
Published: November 2017

The emergence of ideation methods that generate large volumes of early-phase ideas has led to a need for reliable and efficient metrics for measuring the creativity of these ideas. However, existing methods of human judgment-based creativity assessments, as well as numeric model-based creativity assessment approaches suffer from low reliability and prohibitive computational burdens on human raters due to the high level of human input needed to calculate creativity scores. In addition, there is a need for an efficient method of computing the creativity of large sets of design ideas typically generated during the design process. This paper focuses on developing and empirically testing a machine learning approach for computing design creativity of large sets of design ideas to increase the efficiency and reliability of creativity evaluation methods in design research. The results of this study show that machine learning techniques can predict creativity of ideas with relatively high accuracy and sensitivity. These findings show that machine learning has the potential to be used for rating the creativity of ideas generated based on their descriptions.
Design and Comparative Analysis of Linear Guides for Refreshable Braille Displays
Authors: Gupta Varan , Sapra Pulkit , Muralikrishnan Suman , Balakrishnan M. , Rao P. V. M.
Published: November 2017

Linear guides are extensively employed in several industrial applications. Miniaturization, minimal friction, cost efficiency and low maintenance are the major challenges faced while developing a linear motion system. This paper presents design and realization of such systems, overcoming the aforementioned challenges. Linear guidance mechanisms, suitable for implementing latching in Refreshable Braille Displays are proposed, where uniform behavior under eccentric loading is required. Several low cost, reliable and efficient guide mechanisms with predetermined dimensional constraints have been designed. Seven mechanisms are illustrated and analyzed in this paper, which includes both, traditional contact-based mechanisms and compliant mechanisms that offer contact-less motion. The paper further compares the functionality, cost feasibility and ease of manufacturing and assembly of these mechanisms.
Modeling Shear Performance of High-Speed Ridged Nail in Aluminum Joints
Authors: Siripurapu Sundeep Krishna , Luscher Anthony F.
Published: November 2017

The automobile industry is currently moving towards increasing fuel economy by reducing vehicle weight. A high-speed ridged nailing technology is a new technology which can solve the challenges involved with multi-material joining in automobile industry. This study investigated the performance of the high speed ridged nail joints made with Aluminum 6061-T6 in pure shear loading. An LS-DYNA FEA model of high-speed ridged nail joint was developed and model results were validated against corresponding experimental results from pure shear loading tests till failure. It was shown that the proposed shear model agreed with experimental results. A set of sensitivity studies were carried out to identify the influential material model type, influence of petalling and effect of ridge-engagement on the joint strength in shear. The model was further used to simulate performance of high-speed ridged nail joints with different thickness combinations. The findings of these simulations indicate that high-speed ridged nail is a viable solution for material joining. Regression models based on bottom plate thickness were proposed.
Refreshable Braille Display Using Shape Memory Alloy With Latch Mechanism
Authors: Sapra Pulkit , Parsurampuria Ankit Kumar , Muralikrishnan Suman , Gupta Varan , Karthikeyan H. , Bhagavatheesh K. , Venkatesan Arun , Valiyaveetil Sashikumar , Balakrishnan M. , Rao P. V. M.
Published: November 2017

Refreshable Braille Display (RBD) is a device that enables people with blindness to access digital textual content through tactile interface. The use of commercially available RBDs is restricted to affluent individuals and organizations due to their high cost, which restricts their penetration in developing nations. Braille displays based on shape memory alloy actuators are a potential low cost alternative but face the challenge of high power consumption, heat accumulation and low response time. This paper proposes an SMA based actuator with a novel latching mechanism to make RBDs. It also discusses the design and production challenges addressed in making the RBD. It further compares the performance of the current prototypes with previous designs of SMA based RBDs.
Ensemble Prognostics With Degradation-Dependent Weights: Prediction of Remaining Useful Life for Aircraft Engines
Authors: Li Zhixiong , Wu Dazhong , Hu Chao , Terpenny Janis , Shen Sheng
Published: November 2017

The objective of this research is to introduce a new ensemble prognostics method with degradation-dependent weights. Specifically, this method assigns an optimized, degradation-dependent weight to each learner (i.e., learning algorithm) such that the weighted sum of the prediction results from all the learners predicts the RUL of mechanical components with better accuracy. The ensemble prognostic algorithm is demonstrated using a data set collected from an engine simulator. Analysis results show that the predictive model trained by the ensemble learning algorithm outperform the existing methods.
On the Nonlinear Vibration Analysis of Ultra Precision Manufacturing Machines With Mode Coupling
Authors: Bukhari Mohammad , Barry Oumar
Published: November 2017

Nonlinear free undamped vibrations are investigated for ultra-precision manufacturing (UPM) machines with quadratic stiffness. The modes of the system are linearly coupled. The non-resonant case and the bounded internal resonance case are considered. The results of the non-resonant case indicate that the behavior of the system is the same as the linear behavior. However, for the internal resonance case, the results show that the amplitudes are coupled. The results also indicate that the nonlinear frequencies and amplitudes depend not only on the initial conditions, but also on the location of the isolators with respect to the center of gravity of the UPM.
Benchmarking the Performance of a Machine Learning Classifier Enabled Multiobjective Genetic Algorithm on Six Standard Test Functions
Authors: Zeliff Kayla , Bennette Walter , Ferguson Scott
Published: November 2017

Previous work tested a multi-objective genetic algorithm that was integrated with a machine learning classifier to reduce the number of objective function calls. Four machine learning classifiers and a baseline “No Classifier” option were evaluated. Using a machine learning classifier to create a hybrid multiobjective genetic algorithm reduced objective function calls by 75–85% depending on the classifier used. This work expands the analysis of algorithm performance by considering six standard benchmark problems from the literature. The problems are designed to test the ability of the algorithm to identify the Pareto frontier and maintain population diversity. Results indicate a tradeoff between the objectives of Pareto frontier identification and solution diversity. The “No Classifier” baseline multiobjective genetic algorithm produces the frontier with the closest proximity to the true frontier while a classifier option provides the greatest diversity when the number of generations is fixed. However, there is a significant reduction in computational expense as the number of objective function calls required is significantly reduced, highlighting the advantage of this hybrid approach.
Understanding the Sustainability of Eco-Labeled Products When Compared to Conventional Alternatives
Authors: Ferrero Vincenzo J. , Shankar Raman Arvind , DuPont Bryony , Haapala Karl R.
Published: November 2017

Sustainability considerations are becoming an intrinsic part of product design and manufacturing. Today’s consumers rely on package labeling to relay useful information about the environmental impact of a given product. As such, eco-labeling has become an important influence on how consumers interpret the sustainability of products. Three categories of eco-labels are theorized: Type I focuses on the use of labels that are certified by a reputable third party. Type II are eco-labels that are self-declared, potentially lacking scientific merit. Type III eco-labeling indicates the public availability of product LCA data. However, regardless of the type of eco-label used, it is uncertain if eco-labeling directly reflects improved product sustainability. This research focuses on exploring if eco-labeling reflects improved product sustainability by comparing eco-labeled products to conventional alternatives. To do this, we perform a comparative study of eco-labelled and comparable conventional products using a triple bottom line sustainability analysis, including environmental, economic, and social impacts. Here we show that for a selected set of products, eco-labeling does, in fact, have a positive correlation with improved sustainability. However, Type II eco-labeling shows a slight negative correlation with product sustainability. We found only one eco-labeled product (with Type II labeling) that had reduced environmental impact over the conventional alternative. Additionally, the majority of the eco-labeled products in the study are cheaper for the consumer in both initial cost and costs incurred throughout the product’s lifetime. In general, the results confirm that most eco-labels are indicative of improved sustainability. Future research can work towards improving Type II eco-labels, and promote policies that protect against false sustainability claims.
A Load Distribution Model for Planetary Gear Sets
Authors: Hu Yong , Talbot David , Kahraman Ahmet
Published: November 2017

Here, a load distribution model of planetary gear sets is presented capable of dealing with planetary gear sets with any component level and gear set level design variations such as component supporting conditions, different kinds of gear modifications and planetary gear sets with different numbers of equally or unequally spaced planets as well as different gear set kinematic configurations while considering gear mesh phasing. It also accounts for classes of planetary gear set manufacturing and assembly related errors associated with the carrier or gears, i.e. pinhole position errors, run-out errors and tooth thickness errors. Example analyses are provided to indicate the need for a model of this type when studying load distribution of planetary gear sets due to unique loading of the gear meshes associated with planetary gear sets. Comparisons to measurements existing in the literature are provided.
Kinematics and Dynamics Comparison Between Three Parallel Robots for Lower Extremity Rehabilitation
Authors: Dabiri Arman , Sabet Sahand , Poursina Mohammad , Nikravesh Parviz E. , Armstrong David G.
Published: November 2017

Ulceration of the foot is one of the most common complications of diabetes mellitus and diabetes-related cause of hospitalization and lower extremity amputations. There have been proposed several treatments and utilized different devices to prevent or at least improve this. It has been shown physical therapy interventions are the most effective in the treatment of diabetic foot wounds among of all the proposed treatments, where a fully controlled motion in patients’ foot is desired on a pure rotational trajectory. Therefore, parallel robots represent a good candidate for this rehabilitation purpose because of their high accuracy. This paper is devoted to designing optimal structures of three six-degree-of-freedom parallel robots (i.e. Stewart, HEXA, and INRIA Active Wrist) for the lower extremity rehabilitation by the use of the genetic algorithm and Monte Carlo method. For this purpose, several key designing parameters such as the size of the platform, the length of manipulators, actuators’ parameters, and reachable workspace are considered. These designing parameters are optimized such that results in the best systems’ kinematics and dynamics performance. Consequently, the advantages and disadvantages of each platform are discussed.
Autonomous Waste Characterization in Environmentally Conscious Decision Making
Authors: Weinert Kevin , Pandey Vijitashwa , Naranjo Corona Sara , Danielewski Aleksander
Published: November 2017

Product take-back and reuse is an effective way to reduce the environmental footprint of products. Millions of tons of waste are disposed in landfills in the United States, electronic products being of particular concern. While constituting a small fraction of landfilled waste, electronic components account for a majority of the environmental impact. The major challenge in addressing this issue is that the components are functionally obsolete and in a state where their numbers and type are not known. Even with concerted efforts to solve this problem through better design or collection practices, a major unknown is how much actually falls through the cracks and makes it to landfills. Human sorting and identification is impractical, while automating this process has been difficult because of limitations of algorithms to match human ability to discern objects. Deep learning promises to change this. This paper discusses the use of autonomous systems that can scan unorganized heaps of products to identify and catalog components, particularly electronics. This approach can fill an important gap in our knowledge. This paper discusses the testbeds created by the authors which shows promise in accomplishing this task. The paper also discusses the repercussions of such a study and cataloging on design decision-making as well as environmental legislation.
Design Preference Prediction With Data Privacy Safeguards: A Preliminary Study
Authors: Burnap Alexander , Papalambros Panos Y.
Published: November 2017

Design preference models are used widely in product planning and design development. Their prediction accuracy requires large amounts of personal user data including purchase and other personal choice records. With increased Internet and smart device use, sources of personal data are becoming more varied and their capture more ubiquitous. This situation leads to questioning whether there is a trade off between improving products and compromising individual user privacy. To advance this conversation, we analyze how privacy safeguards may affect design preference modeling. We conduct an experiment using real user data to study the performance of design preference models under different levels of privacy. Results indicate there is a tradeoff between accuracy and privacy. However, with enough data, models with privacy safeguards can still be sufficiently accurate to answer population-level design questions.
Village-Scale Electrodialysis Desalination: Field Trial Validation
Authors: Wright Natasha C. , Winter Amos G.
Published: November 2017

This paper presents the design and initial testing of a village-scale photovoltaic (PV) powered electrodialysis reversal (EDR) desalination system for rural India. The system was built by the authors and tested at the Brackish Groundwater National Desalination Research Facility in New Mexico. EDR has the potential to be more cost effective than currently installed village-scale reverse osmosis (RO) systems in off-grid locations due to the lower specific energy consumption of EDR versus RO at high recovery ratios. Lower energetic demand leads to lower solar power system costs for off-grid areas. The system tested in this study is designed to validate that energetic, product water quality, and water recovery requirements can be met. An analytical model of the system that accounts for the composition of natural groundwater is presented and compared to initial experimental results. Additionally, results from the USAID Desal Prize are presented showing the system’s performance in regards to recovery ratio and product water quality. This paper presents the design methodology, resulting system parameters, and experimental results for an initial village-scale PV-EDR field trial.
Efficiently Handling Process Overruns and Underruns on Multiprocessors in Real-Time Embedded Systems
Authors: Xu Jia
Published: November 2017

In hard real-time and embedded multiprocessor system real-world applications, it is very important to strive to minimize the run-time overhead of the scheduler as much as possible, especially in hard real-time and embedded multiprocessor systems with limited processor and system resources. In this paper, we present a method that reduces the worst-case time complexity of the run-time scheduler for re-computing latest start times and for selecting processes for execution on a multiprocessor at run-time to O(n), where n is the number of processes.
An Ensemble Bias-Correction Method With Adaptive Weights for Dynamic Modeling of Lithium-Ion Batteries
Authors: Li Yifei , Sadoughi Mohammad Kazem , Li Zhixiong , Hu Chao
Published: November 2017

Accurate modeling of the electrical behavior of a lithiumion (Li-ion) battery can provide accurate dynamic characteristics of the battery during charging/discharging and relaxation phases, which is essential to accurate online estimation of the battery state of charge (SoC). This paper proposes an ensemble bias-correction (BC) method with adaptive weights to improve the accuracy of an equivalent circuit model (ECM) in dynamic modeling of Li-ion batteries. The contribution of this paper is twofold: (i) the development of a novel ensemble method based on BC learning to model the dynamic characteristics of Li-ion batteries; and (ii) the creation of an adaptive-weighting scheme to learn online the weights of offline member BC models for building an online ensemble BC model. Repeated pulsing tests with single and multiple C-rates were conducted on seven Li-ion battery cells to evaluate the effectiveness of the proposed ensemble BC method. The analysis results with the use of an ECM demonstrate that the proposed method can reduce, on average, the voltage modeling error of the ECM by at least 50%.
Dynamic Modeling and Analysis of Strain Energy and Centrifugal Force Deployment of an Origami Flasher
Authors: Hossain Bhuiyan Md Emran , Semer Daniel , Trease Brian P.
Published: November 2017

Recent research in the field of origami-inspired engineering has seldom considered dynamic analysis of such structures. In this paper, a dynamic model of a flasher (an origami base that packs into a 3D structure that radially deploys completely flat) is created using multi-body dynamic (MBD) simulation software. This model is deployed by two different methods: strain energy and centrifugal force. The MBD model is created automatically by a series of scripts that transform a crease pattern into a fully defined engineering model. The primary focus is to investigate the deployment time, force and torque distribution in the entire structure, bending angle of the panels, and rigid foldability, through parametric studies of the general flasher parameters. The results may help in flasher design decisions where flasher patterns are applicable such as future star occulter designs, solar arrays, and solar sails. Furthermore, the method is general and creates a groundwork for dynamic analysis of other origami structures.
Reduction of Stress in Plastic Compliant Mechanisms by Introducing Metallic Reinforcement
Authors: Crews Joshua , Midha Ashok , Dharani Lokeswarappa R.
Published: November 2017

A method is provided and validated for redesigning compliant segments to improve their fatigue, creep, and stress relaxation performance. The method reduces the bending stress in the polymer portion of the compliant segment without the need for overall mechanism redesign, by introducing metallic reinforcement and by matching the force-deflection response of the redesigned segment to that of the baseline segment. An example redesign case study is presented and validated with experimental testing using a unique deflection testing device designed for fixed-free compliant mechanisms. This vein of research is undertaken using metallic reinforcement (inserts) toward the development of a new class of compliant mechanisms with significantly greater performance, particularly insofar as the problems of fatigue and creep are concerned.
Experimental Investigation and Analysis on Dynamic Strain of Leading Trailing Shoe Drum Brake
Authors: Wang Xiaoying , Fan Zijie , Li Jia , Gui LiangJin
Published: November 2017

The research on the dynamic strain of drum brakes is of great significance in performance evaluation, structure optimization and fatigue prediction. Based on current research of strain experiments and measuring technology, a new test procedure is proposed to investigate strain and temperature information of a working drum. Wireless data acquisition system and high-temperature strain gauges are applied. The strain-time and temperature-time curves are studied on the conditions of emergency brake and continuous brake. A tribological and thermo-mechanical analysis are conducted by using software ABAQUS. Results show that the strain is uneven when the drum contacts different zones of friction plates. Seasonal variation is another feature and a set of four wave crests repeats during the rotation. Meanwhile, thermal effect is proved important to strain. The simulation results coincide well with experiments, proving that this method provides a practical way to verify the calculation. The study also lays the foundation for the following fatigue analysis and optimization design.
Design Rules for Additive Manufacturing: A Categorization
Authors: Mani Mahesh , Witherell Paul , Jee Haeseong
Published: November 2017

Additive manufacturing (AM) is gaining popularity in industrial applications including new product development, functional parts, and tooling. However, due to the differences in AM technologies, processes, and process implementations, functional and geometrical characteristics of manufactured parts can vary dramatically. Planning, especially selecting the appropriate AM process and material requirements can be rather involved. Manufacturability using AM processes has been well studied; however, gaps exist in the design process when catering to the needs of manufacturability. Designers today are challenged with a lack of understanding of AM capabilities, process-related constraints, and their effects on the final product. Challenges are compounded by the ambiguity of where design for AM ends and process planning begins. These ambiguities can be addressed through design principles and corresponding design rules for additively manufacturing parts. The purpose of this paper is to categorically present relevant and reported efforts in design and process planning with design rules in AM. The overarching goal of the review is to offer insights to extract and categorize fundamental principles for derivative rules for different AM processes. Identifying such fundamental requirements could potentially lead to breakthroughs in design and process planning.
Impact of Chaining Method and Level of Completion on Accuracy of Function Structure-Based Market Price Prediction Models
Authors: Gill Amaninder Singh , Summers Joshua D.
Published: November 2017

The goal of this paper is to explore how different modeling approaches to construct function structure models and different levels of model completion affect the information contained within the respective models. Specifically, the models are used to predict market prices of products. These predictions are compared based on their accuracy and precision. This work is based on previous studies on understanding how function modeling is done and how topological information from design graphs can be used to predict information with historical training. It was found that forward chaining was the least favorable chaining type irrespective of the level of completion. Backward chaining models work relatively better across all completion percentages, while Nucleation models don’t perform as well for a higher completion percentage. Hence, a greater attention is needed to understand and employ the methods yielding the most accuracy.
Temperature Rise Real-Time Measurement of Metro Tread Based on the Multi-Sensor Fusion and Online Compensation Method
Authors: Zuo Jianyong , Hu Guo , Zhao Tiefeng , Zuo Lei
Published: November 2017

To study the temperature rise of the metro wheel tread, the simulation is conducted, finding that the highest temperature emerges in the tread area during the braking process, up to 350 °C. The range of temperature measurement should include 0∼350 °C. The temperature rise of the tread surface and the temperature near the side of the wheel tread tend to be consistent after the braking. The temperature measurement on the side of the wheel can provide a reference for the tread temperature measurement. Then several kinds of temperature sensors used for testing the tread temp are introduced, the accuracy and influencing factors of the measurement of the tread surface temperature sensor was analyzed. For the temperature measurement of wheel tread, featuring bright surface emission, low and unstable emissivity, a real-time temperature test method with multi-sensor compensation and data fusion is proposed and a more realistic curve of the tread temperature is obtained. Taking the actual line pure-air brake condition as an example, the above method is used to measure the temperature of tread surface. The results show that the measurement accuracy of multi-sensor data compensation and fusion is better than that of using the single infrared thermometer method, up by 15%; The law of temperature rise is consistent with that of transient simulation. reflecting that this testing method can offer important references to the real-time measurement of tread temperature.
Value of Shear Wave Elastography for differentiating benign and malignant renal lesions
Authors: Aydin Sinem , Yildiz Seyma , Turkmen Ihsan , Sharifov Rasul , Uysal Omer , Gucin Zuhal , Armagan Abdullah , Kocakoc Ercan
Published: November 2017

Aims: To investigate the diagnostic accuracy of shear-wave elastography (SWE) for assessing malignant and benign kidneymasses.Materials and methods: Forty patients with solid renal masses underwent US elastographic evaluation. SWE values of the lesions and adjacent cortical renal parenchyma and SWER were detected prospectively. Malignant tumors were recorded as group 1 and benign tumors were recorded as group 2.Results: The highest elasticity values were 27.27±25.66 kPa for group 1 and 16.13±8.89 kPa for group 2. The mean±SD elasticity values for adjacent renal cortex for groups 1 and 2 were 2.7±2.08 and 2.75±1.35, respectively. For group 1, a negative correlation was observed between the age of the patients and SWER value (p=0.047, rs=‑0.401). There was also a negative correlation between the SWER value and the SWE value of adjacent renal cortex (p=0.004, rs=‑0.555).Conclusion: SWE is a noninvasive method that provides quantitative elasticity informationon tissues. Overlaps among different types of renal lesions may be due to heterogeneity of the lesions. Larger studygroups may clarify the other factors affecting SWE values under both normal and pathological conditions.
Effects of chronic flexed wrist posture on the elasticity and crosssectional area of the median nerve at the carpal tunnel among chronic stroke patients
Authors: Aslan Hulya , Analan Pinar Doruk
Published: November 2017

Aim: To investigate the effects of chronic flexed wrist posture following spasticity on the elasticity and cross-sectional area (CSA) of the median nerve at the carpal tunnel among chronic stroke patients.Material and method: This prospective study included 24 consecutive patients (mean age, 56.5±11.56 years) with unilateral wrist spasticity following a stroke in a chronic phase. The CSA of the median nerve was measured by ultrasound (US). The elasticity was measured by Virtual Touch tissue imaging quantification (VTIQ; Siemens, Erlangen, Germany). SWV and CSA of the median nerves of the affected and unaffected sides for each patient were compared. The correlations between duration of time since the stroke, SWV and CSA of the median nerve were assessed. The interobserver agreement was assessed.Results: The CSA of the median nerve at the affected side was significantly lower than that of the unaffected side (p = 0.03). The SWV of the median nerve at the affected side was significantly higher than that on the unaffected side (p < 0.001). The interobserver agreement was excellent for both CSA and SWV measurements. There was a negatively fair correlation between CSA at the affected side and duration of time since stroke (r = -0.58, p < 0.05). The SWV of the median nerve at the affected side was not correlated with the duration of time since stroke (r ≤ 0.3, p ≥ 0.05).Conclusions: These results suggest that chronic flexed wrist posture may cause atrophy of the median nerve due to chronic compression after stroke and increase in the stiffness of the median nerve.