bluuebunny/crossref_metadata_2025_split huggingface dataset:
Periodic Response and Stability of Flexible Rod Slider Crank Mechanism
Authors: Lee Shyr Wen , Beale David G. 
Published: March 2021

Abstract
Periodic steady state solutions are generated from the nonlinear differential equation of an Euler-Bernoulli beam rod, constant speed crank, slider crank mechanism. The system is approximated by a single ordinary differential equation. To facilitate Harmonic Balance, the response and difficult nonlinear and linear portions of the ODE are expanded into two separate Fourier Series. Harmonic Balance/Fast Fourier Transform method is utilized to determine the harmonic content of each Fourier Series and generate periodic solutions which compared favorably with Runge-Kutta numerical integration. Stability of periodic solutions was examined using the monodromy matrix method. Nondimensional amplitude versus nondimensional crank speed was plotted to examine the effect on dynamic response of external force, piston mass, and crank length. Jump and period doubling bifurcations and regions of amplified response were found.
The Elastic Slider-Crank Mechanism: A Study of the Intrinsic Configuration-Dependent Modal Properties
Authors: Midha Ashok , Karam D. , Thompson B. S. 
Published: March 2021

Abstract
In recent years, an ever-increasing demand has been placed on manufacturing for increased productivity, requiring machines to run faster, quieter and with greater precision. This has necessitated that the elastodynamic behavior of mechanisms be carefully evaluated if better machinery must be designed. Although numerous works have been presented for computing the response of mechanisms containing elements characterized by distributed mass and elasticity, very little has been revealed about their modal properties. This paper addresses the modeling of planar slider-crank mechanisms, a popular class of mechanisms, for geometrically nonlinear, elastodynamic response. A modal analysis is performed for varying positions of the crank, and configuration-dependent natural frequencies and mode shapes are presented as functions of the crank position. The results, which includes a study of the effects of some design parameters on these modal properties, should provide new and valuable insights to the designer and researcher alike. These intrinsic modal properties will directly affect the parametric vibrational response and stability characteristics of elastic slider-crank mechanisms.
An Analytical Method for Locating Velocity Instantaneous Centers
Authors: Yan Hong-Sen , Hsu Meng-Hui 
Published: March 2021

Abstract
An analytical method is presented for locating all velocity instantaneous centers of linkage mechanisms with single or multiple degrees of freedom. The method is based on the fact that the coefficient matrix of the derived velocity equations for vector loops, independent inputs, and instantaneous centers is singular. This approach also works for special cases with kinematic indeterminacy or singular configurations.
Kinematic Analysis and Design of Two-Input, Five-Bar Mechanisms Driven by Relatively Small Cranks
Authors: Basu Partha Sarathi , Farhang Kambiz 
Published: March 2021

Abstract
Single input mechanisms driven by relatively small cranks have been shown to have output link motions which may be approximately described as simple harmonic functions of the input crank angular displacement. This paper presents a mathematical formulation for the approximate analysis and design of two-input, small-crank five-bar mechanisms for function generation. A perturbation technique is employed for the derivation of the approximate equations. Coefficients of the harmonic terms in the output motion equations are obtained from the mechanism geometry and application of the perturbation technique. The output link motions are shown to be approximately described by a linear combination of two simple harmonic functions, in terms of the two input crank angles. The utility of the equations are demonstrated through several mechanism synthesis examples.
An Efficient Algorithm for Finding Optimum Code Under the Condition of Incident Degree
Authors: Jongsma T. J. , Zhang W. 
Published: March 2021

Abstract
This paper deals with the identification of kinematic chains. A kinematic chain can be represented by a weighed graph. The identification of kinematic chains is thereby transformed into the isomorphism problem of graph. When a computer program has to detect isomorphism between two graphs, the first step is to set up the corresponding connectivity matrices for each graph, which are adjacency matrices when considering adjacent vertices and the weighed edges between them. Because these adjacency matrices are dependent of the initial labelling, one can not conclude that the graphs differ when these matrices differ. The isomorphism problem needs an algorithm which is independent of the initial labelling. This paper provides such an algorithm.
Dynamics of Single-Loop Mechanisms With Flexible Links
Authors: Darcovich John , Angeles Jorge , Misra Arun K. 
Published: March 2021

Abstract
A formulation of the dynamical equations of a general, spatial, single-loop mechanism with any combination of rigid and flexible links is developed. This formulation resorts to the natural orthogonal complement (NOC) to eliminate non-working constraint forces from the equations of motion, an approach which offers several advantages. First, the equations of motion are formulated disregarding the non-working constraint forces, since they are eventually eliminated and need not be computed. Secondly, the final equations of motion are described in terms of a minimum number of generalized coordinates, this number being the degree of freedom of the system at hand. Finally, the problems associated with solving a system of differential and algebraic equations, which usually occurs when Lagrange multipliers are introduced, are avoided, since the constraints are incorporated naturally into the differential equations of motion. The above formulation is used to perform dynamic simulations of flexible-link mechanisms with a kinematic loop.
On the Limitations of Predictions of the Dynamic Response of Machines With Clearance Connections
Authors: Deck Joseph F. , Dubowsky Steven 
Published: March 2021

Abstract
The results of experimental and analytical studies of the dynamic response of machines with flexible links and connection clearances are presented. These results suggest that the actual dynamic response of such systems inherently exhibits both a large amount of variability and high sensitivity to small parameter changes and operating conditions. This work suggests that the accuracy of the dynamic force predictions given by computer simulations for such systems is fundamentally limited, and therefore such simulations should be used in system design with care.
Virtual Wedging in Three Dimensional Peg Insertion Tasks
Authors: Sturges Robert H. , Laowattana Schitt 
Published: March 2021

Abstract
Quasi-static wedging of three-point contacts is investigated, wherein the concepts of virtual and redundant wedging due to a resultant force falling into a friction cone are proposed. We consider the fully-started case of a square peg and hole consisting of two point-surface contacts and one line-line contact. An analysis of the wedging diagram for this highly constrained configuration is carried out and compared to the two dimensional case. An approximate wedging diagram is constructed which shows that wedging of square pegs into square holes is more likely than cylindrical pegs and holes of similar sizes.
Selective Robotic Assembly
Authors: Berzak Nir 
Published: March 2021

Abstract
A new approach to robotic high precision selective assembly is presented. The basis for this selective assembly is a gripper which both grips the part to be assembled along its mating planes and inspects its dimensions while gripping. One hundred percent interchangeability of spare parts is achieved by selecting the appropriate parts for inventory, during assembly. Cost reduction and the increase in product quality are shown by example.
Collision-Free Path Generation for Autonomous Manipulators Using Non-Uniform Rational B-Spline (NURBS) via Artificial Transformation
Authors: Soni N. , Shirkhodaie A. , Soni A. H. 
Published: March 2021

Abstract
This paper presents an algorithm for collision free path planning of autonomous manipulators among obstacles. The algorithm uses powerful features of Non-Uniform Rational B-splines (NURBS) to determine the path of the manipulator in the complimentary space of the obstacles. Initially the algorithm artificially transforms the obstacles to point size. It then uses these point obstacles and start & target position of the manipulator as control points to determine a NURBS path which is the initial collision-free path. Obstacles are then iteratively increased in size by small increments. After each increment the new collision control points with obstacles are determined and a new collision-free NURBS path is generated to guide the manipulator through crowded obstacles. This procedure is continued till all the obstacles attain their full size and resulting path is maintained free of collision. The developed algorithm is most suited for manipulators facilitated with range sensors for remote detection of obstacles. The paper details the technique for obtaining a smooth collision-free path of a manipulator moving around a crowded environment with static obstacles.
A Robotic Tool Transformation Teacher
Authors: Hunt Scott E. , Derby Stephen J. 
Published: March 2021

Abstract
The objective of this project was to design and build a system for teaching robot tool transformations. A PUMA and an Adept One robot were used for testing the feasibility of the system. The Tool Transformation Teacher provides for both the manual and programmed control of a robotic manipulator with respect to a tool coordinate system, thus increasing robot flexibility.
Robotic Assembly of Welded Truss Structures in Space
Authors: Jones Clyde S. , Thomas Frank , Brewer William V. 
Published: March 2021

Abstract
A capability for welding in-space as a method of making permanent joints for vehicles and structures assembled on-orbit is under development. This project is part of an in-space assembly and construction program to develop the requirements and technology needed to build elements in space. This paper describes an approach to the welding of tubular truss strut joints for a range of diameters. The conceptual design of a mechanism to position the strut in the truss and weld it in place is also outlined. Considerations for the use of welding as a tool for in-space construction are discussed.
Testing CALS Standards for Engineering and Manufacturing Applications
Authors: Craig J. I. , Fulton Robert E. , Stephen E. R. , Jarnagin A. B. 
Published: March 2021

Abstract
Standards verification in a CALS environment can be a complex and demanding process requiring not only a complete understanding of the standard but also the planned application and software implementation. An area of particular concern is the adequacy of vector or geometry based standards such as IGES to represent engineering and manufacturing applications. In such cases the visual similarity of geometry can be an inadequate test of the validity of a data exchange. Analytically oriented use of the geometry representation of some design and manufacturing applications may require very precise exchange of geometric entities.
This paper will focus on testing strategies to provide comprehensive evaluations of vector based geometry standards such as IGES for engineering analysis, design and manufacturing use. The tests will show effective ways to measure whether vendor translators adequately capture key behavior needed in such applications. Results will be illustrated through tests at the Georgia Tech CALS Research Center which includes several different workstations and associated CAD software systems. CALS Class II test suites taken from representative aerospace applications are used to illustrate these concepts. The results show the importance of such testing in the verification of future CALS standards built around the PDES/STEP efforts. Finally the paper will outline the role and importance of an analytic testing facility in a comprehensive academic research program on information technology for engineering and how it influences current and future engineering education.
Implementing the CAM-I Application Interface Specification With UNIX Interprocess Communication
Authors: Richardson David C. , Magleby Spencer P. 
Published: March 2021

Abstract
The CAM-I Application Interface Specification (AIS) allows applications to access a geometric modeler for model analysis using a standardized interface. This is accomplished by linking the source or object codes of the application and modeler together at compile time along with the AIS implementation for the modeler. This methodology requires at least the object code of both programs and results in a single, large executable program dedicated to the use of the specific application and modeler only. By using interprocess communication (IPC) with the AIS, the two programs can remain separate and be used with other modelers and applications rather than only with each other. The approach used in defining the AIS/IPC adaptation issues and developing and testing concepts to address those issues resulted in successfully implementing AIS using the messaging routines of IPC. This allowed an independent application to invoke and interface with an independent geometric modeler and perform analyses on representative models. The implications of the approach used and the implementation of AIS with IPC in engineering are broad. Using a modified form of the AIS/IPC, an application could theoretically interface with a modeler on a remote system far from the host.
A Product Data Model for Design Support Using Functional Skeletons
Authors: Stadlbauer Harald 
Published: March 2021

Abstract
This paper presents a new method called Functional Skeletons and its usage for a product data model for the design process. The Functional Skeletons represent the main functional flows in a product and allow the efficient storage of designs as well as the generation of verified (in respect to their specification) products. The Functional Skeletons can be used as the basis of a new type of product data models.
Decoupling of Au and As during rapid pyrite crystallization
Authors: Wu Ya-Fei , Evans Katy , Hu Si-Yu , Fougerouse Denis , Zhou Mei-Fu , Fisher Louise A. , Guagliardo Paul , Li Jian-Wei 
Published: March 2021

Abstract
Gold (Au) is largely hosted by pyrite in a variety of hydrothermal systems, but the incorporation of Au into pyrite under disequilibrium conditions remains poorly understood. We integrate synchrotron X-ray fluorescence microscopy, electron backscatter diffraction, nanoscale secondary ion mass spectrometry, and laser ablation–multicollector–inductively coupled plasma–mass spectrometry to constrain the processes that sequester Au into zoned pyrite in the hydrothermal cement of breccia ores from the world-class Daqiao orogenic Au deposit, central China. Euhedral pyrite cores with oscillatory and sector zoning, variable δ34S values, and lower Au-As contents than the mantles are attributed to crystallization during oxidation of metal-depleted ore fluids with local variation in fluid conditions. The isotopically uniform colloform mantles are formed by pyrite crystallites separated by low-angle boundaries and are characterized by unusual decoupling of Au and As. Mantle formation is attributed to rapid disequilibrium precipitation from a metal-rich FeS2-supersaturated fluid. Incorporation of Au into the pyrite mantles was facilitated by abundant lattice defects produced by rapid nucleation. Gold-As–poor pyrite rims were deposited from an evolved ore fluid or other metal-depleted fluids. These results show that chemical variations recorded by fine layering within minerals can provide valuable insights into disequilibrium mass transfer and ore formation. The decoupling between Au and As in pyrite mantles indicates that As is not always a reliable proxy for Au enrichment in rapidly crystallized porous pyrite.
Lack of effect ofLactobacillus rhamnosusGG andBifidobacterium lactisBb12 on beta-cell function in children with newly diagnosed type 1 diabetes: a randomised controlled trial
Authors: Groele Lidia , Szajewska Hania , Szalecki Mieczysław , Świderska Jolanta , Wysocka-Mincewicz Marta , Ochocińska Agnieszka , Stelmaszczyk-Emmel Anna , Demkow Urszula , Szypowska Agnieszka 
Published: March 2021

IntroductionThe gut microbiota may be relevant in the development of type 1 diabetes (T1D). We examined the effects ofLactobacillus rhamnosusGG andBifidobacterium lactisBb12 on beta-cell function in children with newly diagnosed T1D.Research design and methodsChildren aged 8–17 years with newly (within 60 days) diagnosed T1D were enrolled in a double-blind, randomised controlled trial in which they receivedL. rhamnosusGG andB. lactisBb12 at a dose of 109colony-forming units or placebo, orally, once daily, for 6 months. The follow-up was for 12 months. The primary outcome measure was the area under the curve (AUC) of the C-peptide level during 2-hour responses to a mixed meal.ResultsNinety-six children were randomised (probiotics, n=48; placebo n=48; median age 12.3 years). Eighty-eight (92%) completed the 6-month intervention, and 87 (91%) completed the follow-up at 12 months. There was no significant difference between the study groups for the AUC of the C-peptide level. For the secondary outcomes at 6 months, there were no differences between the study groups. At 12 months, with one exception, there also were no significant differences between the groups. Compared with the placebo group, there was a significantly increased number of subjects with thyroid autoimmunity in the probiotic group. However, at baseline, there was also a higher frequency of thyroid autoimmunity in the probiotic group. There were no cases of severe hypoglycemia or ketoacidosis in any of the groups. No adverse events related to the study products were reported.ConclusionsL. rhamnosusGG andB. lactisBb12, as administered in this study, had no significant effect in maintaining the residual pancreatic beta-cell function in children with newly diagnosed T1D. It remains unclear which probiotics, if any, alone or in combination, are potentially the most useful for management of T1D.Trial registration numberNCT03032354.
Incidence and pathophysiology of diabetes in South Asian adults living in India and Pakistan compared with US blacks and whites
Authors: Narayan K M Venkat , Kondal Dimple , Daya Natalie , Gujral Unjali P , Mohan Deepa , Patel Shivani A , Shivashankar Roopa , Anjana Ranjit Mohan , Staimez Lisa R , Ali Mohammed K , Chang Howard H , Kadir Masood , Prabhakaran Dorairaj , Selvin Elizabeth , Mohan Viswanathan , Tandon Nikhil 
Published: March 2021

IntroductionWe compared diabetes incidence in South Asians aged ≥45 years in urban India (Chennai and Delhi) and Pakistan (Karachi), two low-income and middle-income countries undergoing rapid transition, with blacks and whites in the US, a high-income country.Research design and methodsWe computed age-specific, sex-specific and body mass index (BMI)-specific diabetes incidence from the prospective Center for Cardiometabolic Risk Reduction in South Asia Study (n=3136) and the Atherosclerosis Risk in Communities Study (blacks, n=3059; whites, n=9924). We assessed factors associated with incident diabetes using Cox proportional hazards regression.ResultsSouth Asians have lower BMI and waist circumference than blacks and whites (median BMI, kg/m2: 24.9 vs 28.2 vs 26.0; median waist circumference, cm 87.5 vs 96.0 vs 95.0). South Asians were less insulin resistant than blacks and whites (age-BMI-adjusted homeostatic model assessment of insulin resistance, µIU/mL/mmol/L: 2.30 vs 3.45 vs 2.59), and more insulin deficient than blacks but not whites (age-BMI-adjusted homeostasis model assessment of β-cell dysfunction, µIU/mL/mmol/L: 103.7 vs 140.6 vs 103.9). Age-standardized diabetes incidence (cases/1000 person-years (95% CI)) in South Asian men was similar to black men and 1.6 times higher (1.37 to 1.92) than white men (26.0 (22.2 to 29.8) vs 26.2 (22.7 to 29.7) vs 16.1 (14.8 to 17.4)). In South Asian women, incidence was slightly higher than black women and 3 times (2.61 to 3.66) the rate in white women (31.9 (27.5 to 36.2) vs 28.6 (25.7 to 31.6) vs 11.3 (10.2 to 12.3)). In normal weight (BMI <25 kg/m2), diabetes incidence adjusted for age was 2.9 times higher (2.09 to 4.28) in South Asian men, and 5.3 times (3.64 to 7.54) in South Asian women than in white women.ConclusionsSouth Asian adults have lower BMI and are less insulin resistant than US blacks and whites, but have higher diabetes incidence than US whites, especially in subgroups without obesity. Factors other than insulin resistance (ie, insulin secretion) may play an important role in the natural history of diabetes in South Asians.
Leaving no one behind in prison: improving the health of people in prison as a key contributor to meeting the Sustainable Development Goals 2030
Authors: Ismail Nasrul , Lazaris Audrey , O'Moore Éamonn , Plugge Emma , Stürup-Toft Sunita 
Published: March 2021

Worldwide, approximately 11 million people are currently being held in prison, a number that has steadily grown since the turn of the 21st century. The prison population is more likely to suffer from physical and mental ailments both during and prior to their imprisonment due to poverty, social exclusion and chaotic lifestyles. Recognition of people in prison is noticeably absent from the Sustainable Development Goals (SDGs), despite the goals’ ethos of ‘leaving no one behind’.We present the first analysis of how improving the health of people in prison can contribute to achieving 15 SDGs. Relevant indicators are proposed to fulfil these goals while meeting the existing international prison health standards. We also assess the political, economic and social challenges, alongside the unparalleled COVID-19 pandemic that can thwart the realisation of the SDGs. To reach the ‘furthest behind first’, prison health must be at the forefront of the SDGs.
Providing food to patients in primary care to induce weight loss: a systematic literature review
Authors: Ball Lauren , Somerville Mari , Crowley Jennifer , Calleja Zoe , Barnes Katelyn 
Published: March 2021

PurposePrimary care is the ideal setting to promote weight management, warranting innovative ways to support patients. This systematic review aimed to determine whether providing food to patients in primary care can help to reduce body weight.MethodsFour databases were searched for studies that aimed to elicit weight loss by directly providing foodstuffs and/or supplements to patients in primary care settings. Interventions with adults of any gender or race were included. Interventions that involved other components such as exercise classes or education sessions were excluded. The methodological quality of each study was appraised using the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies.ResultsFour heterogeneous studies met the eligibility criteria, representing 476 adults. Two studies used meal-replacement products but differed in length and intensity, another study provided green tea and vitamin E supplementation, and the final study provided vouchers for use at a farmers’ market hosted at a primary care clinic. Interventions ranged in length from 4 to 13 weeks. Three of the four studies observed weight loss in some form and all studies observed at least one other improvement in a health outcome such as waist circumference, blood pressure or fasting insulin levels.ConclusionsA small yet notable body of literature supports the concept of providing food to patients in primary care settings to support weight loss. Further, high-quality research is needed on the efficacy and cost-effectiveness of this approach to ultimately inform policy initiatives for primary care.