bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors influencing the recruitment and retention of female first responders: a mixed methods systematic review protocol
Authors: Frazer Helen , Van Hooff Miranda , Lawrence-Wood Ellie , Searle Amelia 
Published: November 2020

ABSTRACT

Objective:
The objective of this review is to produce a set of integrated findings of quantitative and qualitative evidence regarding workplace recruitment and retention factors (including departure) of female first responders to inform recommendations for policy and practice.

Introduction:
Historically, first responder workforces such as police officers, firefighters, search and rescue personnel, medical technicians, and paramedics have been largely male dominated. Over the past few decades, however, there has been a steady increase in the number of women entering this field. However, there is minimal research examining factors that influence the recruitment/retention of female first responders. The intention of this review is to identify barriers and facilitators to recruitment and retention of female first responders and to identify any differences between sexes/genders.

Inclusion criteria:
This review will summarize qualitative and quantitative research examining factors influencing the recruitment/retention of female first responders. Such factors may include job satisfaction, quality of work life, burnout, compassion fatigue, and intent to remain in the workforce.

Methods:
MEDLINE (PubMed), CINAHL (EBSCO), PsycINFO (APA), PTSDpubs (formerly PILOTS; ProQuest), Embase (Elsevier), and Scopus (Elsevier) will be searched for studies published in English from 2009 to the present. Unpublished studies will be searched in Google Scholar, and ProQuest Dissertations and Theses Global. Both quantitative and qualitative studies will be screened for inclusion and critically appraised for methodological quality by two independent reviewers. Both types of data will be extracted using JBI tools for mixed methods systematic reviews. A convergent integrated approach to synthesis and integration will be used.

Systematic review registration number:
PROSPERO CRD42020156524
Hypoxia gradually augments metabolic and thermoperceptual responsiveness to repeated whole‐body cold stress in humans
Authors: Keramidas Michail E. , Kölegård Roger , Eiken Ola 
Published: November 2020

New Findings
What is the central question of this study?In male lowlanders, does hypoxia modulate thermoregulatory effector responses during repeated whole‐body cold stress encountered in a single day?
What is the main finding and its importance?A ∼10 h sustained exposure to hypoxia appears to mediate a gradual upregulation of endogenous heat production, preventing the progressive hypothermic response prompted by serial cold stimuli. Also, hypoxia progressively degrades mood, and compounds the perceived thermal discomfort, and sensations of fatigue and coldness.
AbstractWe examined whether hypoxia would modulate thermoeffector responses during repeated cold stress encountered in a single day. Eleven men completed two ∼10 h sessions, while breathing, in normobaria, either normoxia or hypoxia (: 12 kPa). During each session, subjects underwent sequentially three 120 min immersions to the chest in 20°C water (CWI), interspersed by 120 min rewarming. In normoxia, the final drop in rectal temperature (Trec) was greater in the third (∼1.2°C) than in the first and second (∼0.9°C) CWIs (P < 0.05). The first hypoxic CWI augmented the Trec fall (∼1.2°C; P = 0.002), but the drop in Trec did not vary between the three hypoxic CWIs (P = 0.99). In normoxia, the metabolic heat production () was greater during the first half of the third CWI than during the corresponding part of the first CWI (P = 0.02); yet the difference was blunted during the second half of the CWIs (P = 0.89). In hypoxia, by contrast, the increase in was augmented by ∼25% throughout the third CWI (P < 0.01). Regardless of the breathing condition, the cold‐induced elevation in mean arterial pressure was blunted in the second and third CWI (P < 0.05). Hypoxia aggravated the sensation of coldness (P = 0.05) and thermal discomfort (P = 0.04) during the second half of the third CWI. The present findings therefore demonstrate that prolonged hypoxia mediates, in a gradual manner, metabolic and thermoperceptual sensitization to repeated cold stress.
Optimal Parametric Control of Nonlinear Random Vibrating Systems
Authors: Chang Wenwen , Jin Xiaoling , Huang Zhilong 
Published: November 2020

Abstract
Due to the great progresses in the fields of smart structures, especially smart soft materials and structures, the parametric control of nonlinear systems attracts extensive attentions in scientific and industrial communities. This paper devotes to the derivation of the optimal parametric control strategy for nonlinear random vibrating systems, in which the excitations are confined to Gaussian white noises. For a prescribed performance index balancing the control performance and control cost, the stochastic dynamic programming equation with respect to the value function is first derived by the principle of dynamic programming. The optimal feedback control law is established according to the extremum condition. The explicit expression of the value function is determined by approximately expressing as a quadratic function of state variables and by solving the final dynamic programming equation. The application and efficacy of the optimal parametric control are illustrated by a random-excited Duffing oscillator and a dielectric elastomer balloon with random pressure. The numerical results show that the optimal parameter control possesses good effectiveness, high efficiency, and high robustness to excitation intensity, and is superior than the associated optimal bounded parametric control.
Insight Into the Non Periodic Motion of the Knife Follower With a Polydyne Cam Mechanism
Authors: Yousuf Louay S. , Dabool Yaakob K. H. 
Published: November 2020

Abstract
A polydyne cam and knife follower system are studied. The effect of cam angular velocity and follower guides internal dimensions on Lyapunov parameter is considered. Wolf algorithm is used to quantify largest Lyapunov exponent parameter. The impact between the cam, follower and the two guides is occurred due to the impulse and momentum phenomenon. Positive value of Lyapunov exponent parameter indicates to non-periodic motion and chaos for the follower. Non-periodic motion is examined using power spectrum analysis of Fast Fourier Transform (FFT) and phase plane diagram. The numerical simulation has been done using SolidWorks software. Follower movement is processed experimentally through an infrared 3-D camera device with a high precision optical sensor. A polydyne cam and knife follower system are studied. The effect of cam angular velocity and follower guides internal dimensions on Lyapunov parameter is considered. Wolf algorithm is used to quantify largest Lya-punov exponent parameter. The impact between the cam, follower and the two guides is occurred due to the impulse and momentum phenomenon. Positive value of Lyapunov exponent parameter indicates to non-periodic motion and chaos for the follower. Non-periodic motion is examined using power spectrum analysis of Fast Fourier Transform (FFT) and phase plane diagram. The numerical simulation has been done using Solid-Works software. Follower movement is processed experimentally through an infrared 3-D camera device with a high precision optical sensor. The simulation and experimental results are compared and verified for non-periodic motion of the follower. The follower motion is non-periodic when the orbit of phase-plane diagram diverges with no limit of spiral cycles.
Design of a Piping Inspection Robot by Optimization Approach
Authors: Venkateswaran Swaminath , Chablat Damien , Hamon Pol 
Published: November 2020

Abstract
This article presents an optimization approach for the design of an inspection robot that can move inside variable diameter pipelines having bends and junctions. The inspection robot uses a mechanical design that mimics the locomotion of a caterpillar. The existing prototype developed at LS2N, France is a rigid model that makes it feasible for working only inside straight pipelines. By the addition of a tensegrity mechanism between motor units, the robot is made reconfigurable. However, the motor units used in the prototype are oversized to pass through pipe bends or junctions. An optimization approach is employed to determine the dimensions of motors and their associated leg mechanisms that can overcome such bends. Two optimization problems are defined and solved in this article. The first problem deals with the determination of motor sizing without leg mechanisms. The second problem deals with the determination of sizing of the leg mechanism with respect to the dimensions of motor units obtained from the first problem. A 3D model of the optimized robot design is then realized using CAD software.
Who, What, and When? Exploring Student Focus in the Capstone Design Experience
Authors: Ball Zachary , Bessette Jonathan , Lewis Kemper 
Published: November 2020

Abstract
Product development is a key component of engineering education taught at a number of universities through their capstone design course. This course provides students with an opportunity to apply their newly obtained knowledge in engineering to design, build, and test working prototypes. This educational approach also encourages students to place additional attention on time and group management. As students walk through the design process, their focus fluctuates between group organization, product development, and course deliverables. This paper observes this variation in focus to extract key insights related to who is focusing on what and when. Data was collected in the form of individual project journals for each student and these provide a detailed look into the design activities throughout the semester allowing for a focus mapping from week to week. The focus of each student is quantified by a topic distribution of each student’s weekly journal entries, automatically extracted using Latent Dirichlet Allocation. Our results place emphasis on the topic identification accuracy and interpretation, before identifying trends found that separate high performing students and groups from those with poor performances. It was found that efficient time management focusing on the required course deliverables, and group cohesion led to the most impactful performance variations. Using this knowledge, we identify future directions supporting the pedagogy for capstone projects.
A Continuously Tunable Stiffness Arm With Cable-Driven Mechanisms for Safe Physical Human-Robot Interaction
Authors: She Yu , Gu Zhaoyuan , Song Siyang , Su Hai-Jun , Wang Junmin 
Published: November 2020

Abstract
In this paper, we present a continuously tunable stiffness arm for safe physical human-robot interactions. Compliant joints and compliant links are two typical solutions to address safety issues for physical human-robot interaction via introducing mechanical compliance to robotic systems. While extensive studies explore variable stiffness joints/actuators, variable stiffness links for safe physical human-robot interactions are much less studied. This paper details the design and modeling of a compliant robotic arm whose stiffness can be continuously tuned via cable-driven mechanisms actuated by a single servo motor. Specifically, a 3D printed compliant robotic arm is prototyped and tested by static experiments, and an analytical model of the variable stiffness arm is derived and validated by testing. The results show that the lateral stiffness of the robot arm can achieve a variety of 221.26% given a morphing angle of 90°. The study demonstrates that the compliant link design could be a promising approach to address safety concerns for safe physical human-robot interactions.
Deconstruction of Idea Generation Methods Into a Framework of Creativity Mechanisms
Authors: Kirjavainen Senni , Hölttä-Otto Katja 
Published: November 2020

Abstract
Creative ideas are a central part of solving engineering problems, generating interesting art, as well as developing successful products and innovations. Idea generation methods are a well-researched topic. Specifically, there is significant research that focuses on specific idea generation methods and how they perform. Further, some method classifications have been suggested to help understand the cognitive mechanisms involved in creative ideation as well as the differences between methods. Yet, the discourse is usually on which ideation method outperforms another or how to improve an ideation method rather than the elements, rules, constraints, and activities that comprise ideation methods. In this study 76 well-documented idea generation methods are reviewed and analyzed. We find all analyzed methods consist of 25 mechanisms. The mechanisms are discussed and classified into idea promoting and implementation mechanisms. We suggest that rather than focusing research only on methods, there should be a parallel track of research creating understanding on these mechanisms and their interactions to help increase our understanding of creativity methods, add practitioners understanding on how to get the best advantages out of creativity methods and lastly improve the way practical creativity is approached in education.
Design, Mobility and Kinematics Analysis of a Novel Reconfigurable Continuum Shape Morphing Mechanism
Authors: Zhao Yinjun , Tian Yingzhong , Li Long , Yuan Guangjie , Xi Fengfeng 
Published: November 2020

Abstract
This paper presents a novel design for morphing mechanisms that combine the passive lockable reconfigurable variable geometry truss manipulator (VGTM) and the active parallel compliant mechanism. The structure of the VGTM is in a parallel-serial structure and its shape can be fully controlled just by using two active panels. This mechanism is suitable for the aerospace application due to its light, compact structure, load-carrying ability and can achieve multiple degrees-of-freedom (DOFs) deformation. The mobility and topological configuration of the mechanism are thoroughly analyzed. To make the moving process simple and efficient, a control strategy combining the approximate motion mode and the precise motion modes was proposed. The kinematic models for the multi-step motion are established and all solved analytically. At last, a prototype was fabricated to show the structure and the application on morphing wings.
Cyber-Physical Infrastructures for Advancing Pyrolysis Conversion Process: A Case Study of Biochar Production
Authors: Hersh Benjamin , Mohajeri Amir , Mirkouei Amin , Xian Min 
Published: November 2020

Abstract
Biomass-based products (bioproducts) have been introduced as a means to address food-energy-water nexus challenges. However, the existing approaches have not been integrated to convert biomass into market-competitive bioproducts (e.g., biochar and bio-oil). Pretreatment and conversion processes represent the most substantial portion of the total bioproduct cost. This study proposes a portable conversion process for high-quality biochar and bio-oil production, using mixed reactors and advanced cyber-physical infrastructures to promote cross-cutting technological and commercialization opportunities. The proposed portable process converts biomass to bioproducts near the collection sites, which can address collection, staging, and logistics challenges. The fundamental novelty of this study lies in utilizing cyber-physical technologies for advancing pre-/post-conversion processes and crossing the boundaries to meet the market needs. A case study for biochar production from various biomass feedstocks is used to demonstrate and verify the application of the conversion process and the cyber-based advances. The results indicate that the integrated cyber-physical conversion pathway can increase process yield and quality. It is also found that biomass properties and conversion process configurations play a crucial role in determining the process yield and biochar quality in terms of the physical-chemical structure.
Cable-Suspended Robot for Algae Harvesting
Authors: Williams Robert L. , Pagan Jesus 
Published: November 2020

Abstract
This paper presents a novel application for a portable 4-cable-suspended point end-effector robot, that of algae harvesting from large (1–4 acres) outdoor circulating pond systems. Algae, used as an alternative energy crop to produce biofuels (and other consumer products), still remain too expensive. One of the greatest expenses in processing algae is the harvesting process. To replace the typical energy-intensive pumping of the entire pond water through algae filters, we propose using a cable-suspended robot to collect algae, which largely then drains while the robot translates the product to a collection point. An additional benefit of our concept, in additional to lower harvesting cost, is that the algae still growing in the pond is not shocked as in the current pumping process, leading to better, healthier yields.
The Stability and Stiffness Analysis of a Dual-Triangle Planar Rotation Mechanism
Authors: Zhao Wanda , Pashkevich Anatol , Klimchik Alexandr , Chablat D. 
Published: November 2020

Abstract
The paper deals with the stiffness analysis and stability study of equilibrium configurations for dual-triangle tensegrity mechanism, which is actuated by adjusting elastic connections between the triangle edges. For this mechanism, the torque-deflection relation was obtained as a function of control inputs and geometric parameters. It was proved that the mechanism can has either a single or three equilibrium configurations that can be both stable and unstable. Corresponding conditions of stability were found allowing user to choose control inputs ensuring the mechanism controllability. The obtained results are confirmed by the simulation examples presented in the paper.
Systems of Systems Engineering to Improve Resilience: A Case Study Comparison of Biologically Inspired and Traditional Approaches
Authors: Watson Bryan C. , Weissburg Marc J. , Bras Bert 
Published: November 2020

Abstract
Systems of Systems (SoS) are networks of systems that operate together synergistically. The response of these SoS to unexpected constituent system failures can undermine their effectiveness. One potential solution is to increase the SoS’s hard (physical design) or soft (human intervention) resilience. The costs and demands on humans increase greater than linearly as SoS scale increases. These limitations require a novel approach to improve SoS resilience. We hypothesize that Biologically Inspired (BID) network design can improve SoS resilience. A systems dynamics model of a Forestry Industry is presented and an optimization search over potential hard and soft resilience approaches is compared to a BID network improvement. SoS resilience is measured through the newly developed SoSRM. Results provide evidence that BID network design provides an approach to increase SoS resilience beyond hard and soft resilience improvements alone (SoSRM increased from .922 to .926). Secondly, this work provides evidence that incorporating detrital actors increases SoS resilience (SoSRM increased from .909 to .926). Third, this paper documents the first case study that uses the new SoSRM metric to justify a design decision. Finally, we provide a counter-example to the theory that increased sustainability always results in increased resilience.
Design of a Compliant Hinge Based on Closed Form Pressure Balancing
Authors: Gomes Robin F. P. , Nijssen Joep P. A. , van Ostayen Ron A. J. 
Published: November 2020

Abstract
Compliant mechanisms consist of a monolithic body and obtain motion through elastic deformation. Multiple compliant flexure designs are known but their translational to rotation stiffness ratio is often limited. This work introduces a novel compliant hinge design with increased stiffness ratio compared to the state of the art compliant hinges. The hinge functions by having an encapsulated fluid medium that contributes to high normal stiffness, but doesn’t influence the rotational stiffness. A 2D design model is presented that shows the effect of the geometry on the stiffness ratio performance. Subsequently, a computational 3D analysis is performed and the resulting design is realized as a demonstrator. The performance is compared to conventional compliant hinges based on the stiffness ratio. This shows an increase of at least a factor 30 on the stiffness ratio.
Mechanical Redesign of a Transtibial Prosthesis With Active and Passive Components and a Four-Bar Mechanism
Authors: Plata Devon K. , Thayer Jessica B. , Voglewede Philip A. 
Published: November 2020

Abstract
This paper proposes a redesign of a four-bar mechanism for an active transtibial prosthesis created by Bergelin 2010 and modified by Klein 2009. Bergelin utilized a four-bar mechanism, motor, and spring to match the prosthesis ankle moments to the ankle moments of a healthy ankle. Bergelin’s prosthesis did succeed in matching ankle moments closely, but with excessive motor energy expenditure when the prosthesis was in a neutral position. Klein proposed a redesign of the mechanism to change the motor-spring connection from parallel to series to eliminate the energy requirement when the device is in neutral position, which allowed for the application of impedance control of mechanism. This paper proposes a reoptimization of the series motor-spring mechanism configuration proposed by Klein, which further reduces the energy input configuration of the active prosthesis.
Two-Dimensional Team Lifting Prediction With Different Box Weights
Authors: Arefeen Asif , Xiang Yujiang 
Published: November 2020

Abstract
A novel multibody dynamics modeling method is proposed for two-dimensional (2D) team lifting prediction. The box itself is modeled as a floating-base rigid body in Denavit-Hartenberg representation. The interactions between humans and box are modeled as a set of grasping forces which are treated as unknowns (design variables) in the optimization formulation. An inverse-dynamics-based optimization method is used to simulate the team lifting motion where the dynamic effort of two humans is minimized subjected to physical and task-based constraints. The design variables are control points of cubic B-splines of joint angle profiles of two humans and the box, and the grasping forces between humans and the box. Two numerical examples are successfully simulated with different box weights (20 Kg and 30 Kg, respectively). The humans’ joint angle, torque, ground reaction force, and grasping force profiles are reported. The joint angle profiles are validated with the experimental data.
Finite Element Models for Flexible Cosserat Solids
Authors: Bauchau Olivier A. , Shan Minghe 
Published: November 2020

Abstract
The application of the finite element method to the modeling of Cosserat solids is investigated in detail. In two- and three-dimensional elasticity problems, the nodal unknowns are the components of the displacement vector, which form a linear field. In contrast, when dealing with Cosserat solids, the nodal unknowns form the special Euclidean group SE(3), a nonlinear manifold. This observation has numerous implications on the implementation of the finite element method and raises numerous questions: (1) What is the most suitable representation of this nonlinear manifold? (2) How is it interpolated over one element? (3) How is the associated strain field interpolated? (4) What is the most efficient way to obtain the discrete equations of motion? All these questions are, of course intertwined. This paper shows that reliable schemes are available for the interpolation of the motion and curvature fields. The interpolated fields depend on relative nodal motions only, and hence, are both objective and tensorial. Because these schemes depend on relative nodal motions only, only local parameterization is required, thereby avoiding the occurrence of singularities. For Cosserat solids, it is preferable to perform the discretization operation first, followed by the variation operation. This approach leads to considerable computation efficiency and simplicity.