bluuebunny/crossref_metadata_2025_split huggingface dataset:
Building a bridge between adaptive capacity and adaptive potential to understand responses to environmental change
Authors: Seaborn Travis , Griffith David , Kliskey Andrew , Caudill Christopher C. 
Published: March 2021

AbstractAdaptive capacity is a topic at the forefront of environmental change research with roots in both social, ecological, and evolutionary science. It is closely related to the evolutionary biology concept of adaptive potential. In this systematic literature review, we: (1) summarize the history of these topics and related fields; (2) assess relationship(s) between the concepts among disciplines and the use of the terms in climate change research, and evaluate methodologies, metrics, taxa biases, and the geographic scale of studies; and (3) provide a synthetic conceptual framework to clarify concepts. Bibliometric analyses revealed the terms have been used most frequently in conservation and evolutionary biology journals, respectively. There has been a greater growth in studies of adaptive potential than adaptive capacity since 2001, but a greater geographical extent of adaptive capacity studies. Few studies include both, and use is often superficial. Our synthesis considers adaptive potential as one process contributing to adaptive capacity of complex systems, notes “sociological” adaptive capacity definitions include actions aimed at desired outcome (i.e., policies) as a system driver whereas “biological” definitions exclude such drivers, and suggests models of adaptive capacity require integration of evolutionary and social–ecological system components.
Distinguishing veterans with suicidal ideation from suicide attempt history: The role of emotion reactivity
Authors: Gromatsky Molly , Edwards Emily R. , Sullivan Sarah R. , Goodman Marianne , Hazlett Erin A. 
Published: March 2021

AbstractIntroductionGrowing evidence suggests emotion reactivity—sensitivity and intensity of emotional experience—may represent a diathesis for suicide risk. However, our understanding of its ability to differentiate risk for suicidal ideation (SI) from suicide attempt (SA) is limited.MethodThis study compares Veterans with SI (n = 81) to Veterans with SA (n = 177) history on factors relevant to emotion reactivity to determine which variable(s) best differentiate groups. Variables examined are multimodal: (a) self‐report: childhood trauma, combat exposure; (b) clinician‐assessed: non‐suicidal self‐injury (NSSI), structured diagnostic interview of psychopathology; and (c) psychophysiological: affect‐modulated startle (AMS; proxy for amygdala reactivity and emotion reactivity) to unpleasant pictures was examined in a subset (n = 90).ResultsSA history was independently predicted by NSSI history, MDD, PTSD, and SUD diagnosis. Childhood trauma and combat exposure did not differentiate groups. The composite risk index demonstrated good accuracy (AUC=0.71, sensitivity=0.90, specificity=0.49). Only AMS independently predicted SA history when added to the model and accuracy was improved (AUC=0.82, sensitivity=0.85, specificity=0.56).ConclusionNSSI history, MDD, PTSD, and SUD diagnosis may be salient risk factors for this population. However, emotion reactivity is a more parsimonious predictor of SA history among Veterans suggesting it is an important treatment target among Veterans with SI.
A Rapid Recursive Experimental Approach to Structure/Control Re-Design
Authors: Pil Anton , Asada Haruhiko 
Published: March 2021

Abstract
This paper introduces an experimental recursive method for simultaneously changing both the mechanical structure and control design of mechatronic systems in order to improve the system’s overall performance. The method improves a system’s closed-loop control specifications through recursive concurrent structure reinforcement and control gain optimization. By using a process of structural reinforcement, a single prototype structure can be used repeatedly until the system performance goals are achieved. To determine the optimal incremental structure changes, a recursive algorithm based on a gradient descent method and a parameter estimation theory is employed. After the incremental structure reinforcements are applied, the control parameters are optimized with respect to multiple control specifications. Next, the resulting system incorporating the structure and control changes is tested and compared with the desired level of performance. The entire process consisting of experimental evaluation, data analysis, and structure reinforcement is repeated until the system performance achieves the desired level. Simulation experiments are successful in changing both the structural and control parameters of a simplified positioning system and show improvement in the system’s overall settling time.
A Probabilistic Tolerance Allocation Method for Dynamic Mechanical Systems With Periodic Response and Discontinuous Forcing Functions
Authors: Zhang F. , Gilmore B. J. , Sinha A. 
Published: March 2021

Abstract
Tolerance allocation standards do not exist for mechanical systems whose response are time varying and are subjected to discontinuous forcing functions. Previous approaches based on optimization and numerical integration of the dynamic equations of motion encounter difficulty with determining sensitivities around the force discontinuity. The Alternating Frequency/Time approach is applied here to capture the effect of the discontinuity. The effective link length model is used to model the system and to account for the uncertainties in the link length, radial clearance and pin location. Since the effective link length model is applied, the equations of motion for the nominal system can be applied for the entire analysis. Optimization procedure is applied to the problem where the objective is to minimize the manufacturing costs and satisfy the constraints imposed on mechanical errors and design variables. Examples of tolerance allocation are presented for a single cylinder internal combustion engine.
A Heuristic Method for Two-Dimensional Layout Problems
Authors: Zhang Xiong , Zhou Ji 
Published: March 2021

Abstract
This paper presents a method for an often encountered two-dimensional layout problem in the shipbuilding and manufacture industries. For a ordered set of irregular as well as rectangular pieces, the system produces rectangles called modules for the pieces at first, and then places these modules into given rectangular sheets of fixed dimensions such that the number of sheets used is minimized. The system also provides the user with an interaction procedure in order to make itself as flexible as possible. This heuristic method has been implemented on IBM PC/AT 486 and compatible computers and is supported by AutoCAD system.
Kinematic Analysis of Tendon Driven Mechanisms Using Signal Flow Graphs
Authors: Chew M. , Escobedo-Torres J. , Huerta-Ochoa R. 
Published: March 2021

Abstract
The application of signal flow graphs has been applied to the kinematic analysis of tendon driven mechanisms. Signal flow graphs have been used in the many areas particularly in the area of control for determining the closed-loop function of a control system. An application of this approach brings the kinematic analysis of tendon driven mechanisms a step towards dynamic analysis and control of these same mechanisms, all within the same framework. Rules directly relating to the application of this technique to tendon driven mechanisms have been developed along with a stepwise description of the construction of signal flow graphs. The resulting graphs permit a direct solution to the kinematic relationships between the output and the input to the mechanism.
Preliminary Robust Design Using Advanced Spreadsheet Modeling Techniques
Authors: Eggert R. J. 
Published: March 2021

Abstract
Robust design methods such as the worst case, random variable calculus and Monte Carlo simulation are useful in minimizing undesirable effects on product reliability, quality and dependability. While the Monte Carlo method provides meaningful qualitative and quantitative results, it has been difficult to implement without specialized computer software. A new preliminary robust design methodology has been developed which overcomes this problem. New spreadsheet features and advanced modeling techniques are presented which implement the Monte Carlo simulation approach. The preliminary robust design of a transmission shaft is presented which illustrates the new modeling techniques.
Determination of Residual Stresses Induced by Hardened Steel Turning Using Finite Element Methods
Authors: Yang Guang , Tite Caroline Norma Jane , Smith Graham Thomas , Hope Anthony David , Noroozi Siamak 
Published: March 2021

Abstract
A method of using the finite element mode to predict the residual stresses on the surface of machined hardened steel is proposed. The proposed model is based on the analysis of strain relaxation data obtained from the measurement of residual stresses by material removal methods involving two stages; 1). experimental determination of the thermal residual stresses produced during heat treatment 2). experimental determination of the resultant residual stress on the machined surface due to the interaction between thermal stress relief and the machining stresses induced. The proposed finite element model was used to determine the relationship between the two types of residual stress within the machined surface region of a workpiece. It was found that the remaining residual stresses are determined mainly by stress release rather than induction. Such a finite element approach aims at an improvement in accuracy and reduction in the number of experiments required to determine the nature of residual stresses. Furthermore, it could provide an improved qualitative assessment of residual stresses when applied to hardened steel turning.
Application of the Thermoelastic Effect to the Stress Analysis of Structural Adhesive Connections
Authors: Gonçalves J. P. M. , Oliveira F. M. F. , de Castro P. M. S. T. , Fernandes A. A. 
Published: March 2021

Abstract
The experimental stress analysis technique using the thermoelastic effect is quite recent. Besides being a non-contact method, the technique is able to produce a full field analysis. These attributes, associated with the possibility of application to structures or components in their operating environment, make the technique appealing for use in an industrial context.
The thermoelastic effect is the change in temperature arising from the change in the stress state of a solid. The stress analysis technique using this effect measures the infra-red radiation emitted from a modification in its stress state. The applicability of the relationship between change in temperature and change in the stress state, as described in the theory of thermoelasticity, requires the existence of adiabatic conditions. Thus, the body to be studied must be subjected to a cyclic loading of a frequency sufficient to ensure those conditions.
Adhesives are being used increasingly in more demanding applications not only in non-load carrying situations but also in structural applications as an alternative to other joining techniques. The use of adhesives in structural applications requires understanding the global behavior of structures as well as the behavior of the adhesive connections. Stress analysis of those connections is an important step towards that goal.
Lap-shear joints are a type of adhesive connections widely used in industrial applications, namely, in the aerospace and automotive industries. In this study, stress analyses of these connections were performed.
The experimental stress analysis technique using the thermoelastic effect was used to determine the stress state at a surface of adhesive lap-shear joints. The results were compared with finite element analyses of the same joints.
Set Based Hierarchical Design: A Constraint Satisfaction Approach
Authors: Bliek Christian 
Published: March 2021

Abstract
Many are the literature reviews where constraint satisfaction is rejected as a candidate solution for design automation. Some point to the combinatorial complexity associated with the solution of large constraint satisfaction problems, others claim it is inadequate to handle the uncertainty prominent in engineering design. In this paper we present a new approach in which hierarchical decomposition techniques exploit sensitivity to reduce combinatorial complexity and uncertainty is modeled using conservative enclosures of sets of possible solutions.
Activity Analysis: Simplifying Optimal Design Problems Through Qualitative Partitioning
Authors: Williams Brian C. , Cagan Jonathan 
Published: March 2021

Abstract
Activity analysis is introduced as a means to strategically cut away subspaces of a design problem that can quickly be ruled out as suboptimal. This results in focused regions of the space in which additional symbolic or numerical analysis can take place. Activity analysis is derived from a qualitative abstraction of the Karush-Kuhn-Tucker conditions of optimality, used to partition an optimization problem into regions which are nonstationary and qualitatively stationary (qstationary). Activity analysis draws from the fields of gradient-based optimization, conflict-based approaches of combinatorial satisficing search, and monotonicity analysis.
Functional Tolerancing: A Design for Manufacturing Methodology
Authors: Srinivasan R. S. , Wood Kristin L. , McAdams Daniel 
Published: March 2021

Abstract
The problem addressed in this paper is the development of a physico-mathematical basis for mechanical tolerances. The lack of such a basis has fostered a decoupling of design (function) and manufacturing. The groundwork for a tolerancing methodology is laid by a model of profile errors, whose components are justified by physical reasoning and estimated using mathematical tools. The methodology is then presented as an evolutionary procedure. This procedure harnesses the various tools to analyze profiles in terms of a minimum set of profile parameters and to re-generate them from the parameters. This equips the designer with a rational means for estimating performance prior to manufacturing, hence integrating design and manufacturing. The utility of the functional tolerancing methodology is demonstrated with performance simulations of a lathe-head-stock design, focusing on gear transmission with synthesized errors.
Manufacturability: Metrics and Perceptions
Authors: Hight Tim , Hornberger Lee , Last Melissa 
Published: March 2021

Abstract
A project was undertaken at Sun Microsystems, Inc. to benchmark DFMA on two workstations. Using both standard DFMA metrics and indirect process metrics, as well as interviews and discussions with development team members, the two products were found to be similar. Incongruities were noted, however, between perceptions of the products and the results of the analysis. Perceptions significantly impacted design decisions in the absence of readily available DFMA metrics.
Design and Implementation of a Virtual Groupware for Layout Decision Problems
Authors: Banerjee A. , Banerjee P. , Mehrotra S. 
Published: March 2021

Abstract
An exploratory virtual reality-based groupware architecture is described as a computerized platform for simultaneously addressing qualitative and quantitative factors in layout problems. The motivation is to narrow this gap between the output of a computerized layout design optimization method and its implementation in practice. The steps involved in formulating and modeling the problem and in implementing a solution methodology are outlined. As part of our ongoing research, the groupware is currently designed to take input from a computerized optimization model for layout design and detailed layout design information such as 3-dimensional geometric, topological, graphics (rendering and texture mapping) and motion information. The groupware can have upto four members in a group who can collaboratively interact to manipulate a detailed layout Pairwise exchange and repositioning of individual layout objects are currently considered.
Design and Analysis of Fluidless Cooling Devices for High Speed Machining
Authors: Billatos Samir B. , Basaly Nadia A. 
Published: March 2021

Abstract
In high speed machining, the generated heat produces very high temperatures at the tool-work interface. Heat generated at the cutting area may shorten tool life, damage work piece surface, affect surface characteristics, and hence increase production cost. To deal with these problems, cutting fluids are used. Unfortunately, these fluids cause harmful effects to the operators and serious problems of pollution to the environment. Therefore, a new approach is developed to reduce the cutting tool temperature without using external coolants, and thus considerably reduce the amount of the hazardous waste being disposed to the environment. It removes a portion of the generated heat from the tool-work interface by flowing water in a closed cooling cycle system. The approach was analyzed and verified using Finite Element Analysis. Results were compared to the dry and wet cutting cases obtained from literature, and it was found that temperatures on the flank and rake faces of the tool can be lowered, and the overheated area of the tool tip, and consequently its wear, can be reduced significantly.
Automated High Level Process Planning for Agile Manufacturing
Authors: Gupta S. , Herrmann J. W. , Lam G. , Minis I. 
Published: March 2021

Abstract
Agile manufacturing combines the strengths of qualified partners in a virtual organization to meet a certain market need. High level process planning is a way to aid designers to improve their design with respect to the capabilities of potential partners. An automated high level process planning system for mechanical components has been developed which considers both global and partner-specific manufacturing capabilities so that cost, cycle time, and quality attributes can be derived for a given design. The system generates a set of manufacturing operations and candidate partner plants that can contribute to the manufacture of the candidate design. The most promising process plans resulting from this process may be used be used to select the most suitable partners for the virtual enterprise.
The Development of a Real Time Recursive Frequency Based Active Chatter Controller
Authors: Kim Sun , Ousterhout Karl B. 
Published: March 2021

Abstract
In most machining processes, large amounts of energy are needed to accomplish the machining operation. When this energy is transmitted through a structure that has minimal damping characteristics, such as a lathe or a milling machine, self sustained oscillations (chatter) can develop. When chatter develops, it can be viewed as a basic performance limitation of the machine tool. In order to suppress the chatter, a real-time controller using digital signal processing techniques has been implemented. This paper discusses a novel method for the real time computation of the transfer function of the machine tool-workpiece combination and illustrates how a real-time active chatter controller can be designed and integrated into existing machine tools to overcome this performance limitation.
Parametric Resonances of a Cantilevered Pipe Conveying Fluid: A Nonlinear Analysis
Authors: Semler C. , Païdoussis M. P. 
Published: March 2021

Abstract
This paper deals with the nonlinear dynamics and the stability of cantilevered pipes conveying fluid, where the fluid has a harmonic component of flow velocity, assumed to be small, superposed on a constant mean value. The mean flow velocity is near the critical value for which the pipe becomes unstable by flutter through a Hopf bifurcation. The partial differential equation is transformed into a set of ordinary differential equations (ODEs) using the Galerkin method. The equations of motion contain nonlinear inertial terms, and hence cannot be put into standard form for numerical integration. Various approaches are adopted to tackle the problem: (a) a perturbation method via which the nonlinear inertial terms are removed by finding an equivalent term using the linear equation; the system is then put into first-order form and integrated using a Runge-Kutta scheme; (b) a finite difference method based on Houbolt’s scheme, which leads to a set of nonlinear algebraic equations that is solved with a Newton-Raphson approach; (c) the stability boundaries are obtained using an incremental harmonic balance method as proposed by S.L. Lau. Using the three methods, the dynamics of the pipe conveying fluid is investigated in detail. For example, the effects of (i) the forcing frequency, (ii) the perturbation amplitude, and (iii) the flow velocity are considered. Particular attention is paid to the effects of the nonlinear terms. These results are compared with experiments undertaken in our laboratory, utilizing elastomer pipes conveying water. The pulsating component of the flow is generated by a plunger pump, and the motions are monitored by a noncontacting optical follower system. It is shown, both numerically and experimentally, that periodic and quasiperiodic oscillations can exist, depending on the parameters.
On the Analysis of Time-Periodic Nonlinear Hamiltonian Dynamical Systems
Authors: Butcher Eric A. , Sinha S. C. 
Published: March 2021

Abstract
In this paper, some analysis techniques for general time-periodic nonlinear Hamiltonian dynamical systems have been presented. Unlike the traditional perturbation or averaging methods, these techniques are applicable to systems whose Hamiltonians contain ‘strong’ parametric excitation terms. First, the well-known Liapunov-Floquet (L-F) transformation is utilized to convert the time-periodic dynamical system to a form in which the linear pan is time invariant. At this stage two viable alternatives are suggested. In the first approach, the resulting dynamical system is transformed to a Hamiltonian normal form through an application of permutation matrices. It is demonstrated that this approach is simple and straightforward as opposed to the traditional methods where a complicated set of algebraic manipulations are required. Since these operations yield Hamiltonians whose quadratic parts are integrable and time-invariant, further analysis can be carried out by the application of action-angle coordinate transformation and Hamiltonian perturbation theory.
In the second approach, the resulting quasilinear time-periodic system (with a time-invariant linear part) is directly analyzed via time-dependent normal form theory. In many instances, the system can be analyzed via time-independent normal form theory or by the method of averaging. Examples of a nonlinear Mathieu’s equation and coupled nonlinear Mathieu’s equations are included and some preliminary results are presented.
Nonlinear Structural Damping Described by the Masing Model and the Method of Slowly Varying Amplitude and Phase
Authors: Gutzer Ulrich , Seemann Wolfgang , Hagedorn Peter 
Published: March 2021

Abstract
In this paper we investigate vibrations of discrete and continuous systems with damping of the MASING type. For free vibrations the method of the slowly varying amplitude and phase shows good agreement with numerical results, especially if the damping is small. The equations resulting from this method allow a faster identification of the parameters of a physical model. First, a single degree of freedom system is studied. Explicit formulae are obtained for the changing amplitude and frequency. The results are useful since damping laws of the type under consideration are well suited to describe the energy dissipation in a variety of real structures. In the second part we consider a one dimensional continuum with a distributed MASING model. An explicit formula is found for the dissipated energy per cycle and wavelength in standing waves.