bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical outcomes of deep brain stimulation for obsessive‐compulsive disorder: Insight as a predictor of symptom changes
Authors: Acevedo Nicola , Rossell Susan , Castle David , Groves Clare , Cook Mark , McNeill Peter , Olver James , Meyer Denny , Perera Thushara , Bosanac Peter
Published: November 2023

Aim

Deep brain stimulation (DBS) is a safe and effective treatment option for people with refractory obsessive‐compulsive disorder (OCD). Yet our understanding of predictors of response and prognostic factors remains rudimentary, and long‐term comprehensive follow‐ups are lacking. We aim to investigate the efficacy of DBS therapy for OCD patients, and predictors of clinical response.

Methods

Eight OCD participants underwent DBS stimulation of the nucleus accumbens (NAc) in an open‐label longitudinal trial, duration of follow‐up varied between 9 months and 7 years. Post‐operative care involved comprehensive fine tuning of stimulation parameters and adjunct multidisciplinary therapy.

Results

Six participants achieved clinical response (35% improvement in obsessions and compulsions on the Yale Brown Obsessive Compulsive Scale (YBOCS)) within 6–9 weeks, response was maintained at last follow up. On average, the YBOCS improved by 45% at last follow up. Mixed linear modeling elucidated directionality of symptom changes: insight into symptoms strongly predicted (P = 0.008) changes in symptom severity during DBS therapy, likely driven by initial changes in depression and anxiety. Precise localization of DBS leads demonstrated that responders most often had their leads (and active contacts) placed dorsal compared to non‐responders, relative to the Nac.

Conclusion

The clinical efficacy of DBS for OCD is demonstrated, and mediators of changes in symptoms are proposed. The symptom improvements within this cohort should be seen within the context of the adjunct psychological and biopsychosocial care that implemented a shared decision‐making approach, with flexible iterative DBS programming. Further research should explore the utility of insight as a clinical correlate of response. The trial was prospectively registered with the ANZCTR (ACTRN12612001142820).
Genotype‐dependent Strategies to “Overcome” Excessive Light: Insights into Non‐Photochemical Quenching under High Light Intensity
Authors: Shomali Aida , Aliniaeifard Sasan , Mohammadian Mohammad , Lotfi Mahmoud , Kalaji Hazem M.
Published: November 2023

High light (HL) intensities have a significant impact on energy flux and distribution within photosynthetic apparatus. To understand the effect of high light intensity (HL) on the HL tolerance mechanisms in tomatoes, we examined the response of the photosynthesis apparatus of 12 tomato genotypes to HL. A reduced electron transfer per reaction center (ET0/RC), an increased energy dissipation (DI0/RC) and non‐photochemical quenching (NPQ), along with a reduced maximum quantum yield of photosystem II (FV/FM), and performance index per absorbed photon (PIABS) were common HL‐induced responses among genotypes; however, the magnitude of those responses was highly genotype‐dependent. Tolerant and sensitive genotypes were distinguished based on chlorophyll fluorescence and energy‐quenching responses to HL. Tolerant genotypes alleviated excess light through energy‐dependent quenching (qE), resulting in smaller photoinhibitory quenching (qI) compared to sensitive genotypes. Quantum yield components also shifted under HL, favoring the quantum yield of NPQ (ՓNPQ) and the quantum yield of basal energy loss (ՓN0), while reducing the efficient quantum yield of PSII (ՓPSII). The impact of HL on tolerant genotypes was less pronounced. While the energy partitioning ratio did not differ significantly between sensitive and tolerant genotypes, the ratio of NPQ components, especially qI, affected plant resilience against HL. These findings provide insights into different patterns of HL‐induced NPQ components in tolerant and sensitive genotypes, aiding the development of resilient crops for heterogeneous light conditions.
Towards a ‘systems’ approach for viral challenge experiments in shrimp: Reporting guidelines for publication
Authors: Arbon P. M. , Andrade Martinez M. , Jerry D. R. , Condon K.
Published: November 2023

The success of contemporary disease management strategies in shrimp aquaculture, such as the ‘systems’ approach, is predicated on robust knowledge of the conditions and interactions between the host, pathogen and environment that promote disease. Pathogen challenge experiments (PCEs) are a power tool for investigating these conditions and interactions. However, absence of accurately reported experimental detail in published PCEs limits scientific transparency, reproducibility, and the potential for the research to make progressive advancements contributing to contemporary shrimp disease management strategies. This review identifies and discusses key factors relating to the host (shrimp), pathogen (virus), and environment that should be carefully considered during the design and publication of PCEs. We offer substantial evidence of their impact on viral disease outcomes, drawn from the existing body of literature, to supporting their consideration. The prevalence of reported experimental details for these factors across 186 viral PCEs in shrimp were evaluated. The review highlights a concerning paucity of experimental detail reported in published shrimp PCEs. We propose a checklist for the minimum reportable information in the publication of shrimp viral PCEs, hereafter referred to as the Shrimp PCE Reporting Guidelines (SPERG). The guidelines aim to enhance the transparency and standardisation of reporting in published PCEs, ensuring that key factors pertaining to the shrimp, pathogen, and environment are adequately considered and documented. Adoption of SPERG is envisaged to empower researchers, reviewers, and readers to assess the internal and external validity of PCEs, facilitating critical evaluation and improved utility of PCE findings for contemporary disease management.
Connecting adolescent friendships to physical health outcomes: A narrative review
Authors: Ehrhardt Alexandra D. , Schacter Hannah L.
Published: November 2023

Friendships are developmentally significant peer relationships that meaningfully contribute to adolescent adjustment. Despite extensive evidence that friendships contribute to adolescents’ psychological well‐being and mental health, less is known about the connections between adolescents’ friendships and physical health outcomes. Therefore, the current review synthesizes a growing body of research examining associations between adolescent friendships and physical health. The findings reviewed provide evidence for links between the quantity, quality, and stability of adolescents’ friendships and their corresponding subjective and physiological health. Consistency of findings varied as a function of friendship dimensions and health outcomes studied. In turn, we end the review with a discussion of conceptual and methodological consistencies and inconsistencies across the studies reviewed, a proposed agenda for future research, and a presentation of a novel process‐oriented model explaining how friendships may contribute to adolescent physical health.
Improved capacity for the repair of photosystem II via reinforcement of the translational and antioxidation systems in Synechocystis sp. PCC 6803
Authors: Napaumpaiporn Pornpan , Ogawa Takako , Sonoike Kintake , Nishiyama Yoshitaka
Published: November 2023

In the cyanobacterium Synechocystis sp. PCC 6803, translation factor EF‐Tu is inactivated by reactive oxygen species (ROS) via oxidation of Cys82 and the oxidation of EF‐Tu enhances the inhibition of the repair of photosystem II (PSII) by suppressing protein synthesis. In our present study, we generated transformants of Synechocystis that overexpressed a mutated form of EF‐Tu, designated EF‐Tu (C82S), in which Cys82 had been replaced by a Ser residue, and ROS‐scavenging enzymes individually or together. Expression of EF‐Tu (C82S) alone in Synechocystis enhanced the repair of PSII under strong light, with the resultant mitigation of PSII photoinhibition, but it stimulated the production of ROS. However, overexpression of superoxide dismutase and catalase, together with the expression of EF‐Tu (C82S), lowered intracellular levels of ROS and enhanced the repair of PSII more significantly under strong light, via facilitation of the synthesis de novo of the D1 protein. By contrast, the activity of photosystem I was hardly affected in wild‐type cells and in all the lines of transformed cells under the same strong‐light conditions. Furthermore, transformed cells that overexpressed EF‐Tu (C82S), superoxide dismutase, and catalase were able to survive longer under stronger light than wild‐type cells. Thus, the reinforced capacity for both protein synthesis and ROS scavenging allowed both photosynthesis and cell proliferation to tolerate strong light.
Repeat patient Testing‐Quality control: An example of implementation in a network of commercial laboratories
Authors: Freeman Kathleen P. , Daly Susan , Flatland Bente
Published: November 2023

The theory and calculations underpinning Repeat Patient Testing‐Quality Control (RPT‐QC) have been presented in prior publications. This paper gives an example of the process used for implementing RPT‐QC in a network of veterinary commercial reference laboratories and the stages associated with the transition to the sole use of RPT‐QC. To employ RPT‐QC in this commercial laboratory network, eight stages of implementation were identified: (1) education, (2) data collection, (3) calculations, (4) QC recording and documentation, (5) running RPT‐QC in parallel with a commercially available quality control material (QCM), (6) development of a Standard Operating Procedure (SOP), (7) development of complementary aspects supporting RPT‐QC, and (8) sole use of RPT‐QC. Advantages of RPT‐QC included cost savings for QCM and External Quality Assessment (EQA) participation and the ability to use commutable specimens with a veterinary matrix at a result level that is of clinical significance for the species. A disadvantage of RPT‐QC using a single level of control was the inability to demonstrate stable performance over a range of results. Future avenues for investigation include ongoing refinement of control limits using a pooled standard deviation of the duplicates (SDdup), Sdup over time, investigation of blood samples from species other than the dog, and manipulation of specimens to produce “low abnormal” or “high abnormal” RPT‐QC specimens.
Quantifying refractive error in companion dogs with and without nuclear sclerosis: 229 eyes from 118 dogs
Authors: Francis Jenelle M. , Mowat Freya M. , Ludwig Allison , Hicks Jacqueline M. , Pumphrey Stephanie A.
Published: November 2023

Objective

To evaluate the relationship between nuclear sclerosis (NS) and refractive error in companion dogs.

Animals studied

One hundred and eighteen companion dogs.

Procedures

Dogs were examined and found to be free of significant ocular abnormalities aside from NS. NS was graded from 0 (absent) to 3 (severe) using a scale developed by the investigators. Manual refraction was performed. The effect of NS grade on refractive error was measured using a linear mixed effects analysis adjusted for age. The proportion of eyes with >1.5 D myopia in each NS grade was evaluated using a chi‐square test. Visual impairment score (VIS) was obtained for a subset of dogs and compared against age, refractive error, and NS grade.

Results

Age was strongly correlated with NS grade (p < .0001). Age‐adjusted analysis of NS grade relative to refraction showed a mild but not statistically significant increase in myopia with increasing NS grade, with eyes with grade 3 NS averaging 0.58–0.88 D greater myopia than eyes without NS. However, the myopia of >1.5 D was documented in 4/58 (6.9%) eyes with grade 0 NS, 12/91 (13.2%) eyes with grade 1 NS, 13/57 (22.8%) eyes with grade 2 NS, and 7/23 (30.4%) eyes with grade 3 NS. Risk of myopia >1.5 D was significantly associated with increasing NS grade (p = .02). VIS was associated weakly with refractive error, moderately with age, and significantly with NS grade.

Conclusions

NS is associated with visual deficits in some dogs but is only weakly associated with myopia. More work is needed to characterize vision in aging dogs.
Preparation of a Novel Proton Exchange Membrane Using Radiation Grafted ETFE Film for Fuel Cell
Authors: Sultana Shahnaz , Rahman Nazia , Sardar Md. Nabul , Hossain A. K. M. Akther
Published: November 2023

For many different applications, functional polymeric materials are extremely important in electrochemical reactions. The development of polymer electrolytes, such as those used in fuel cells, depends heavily on these functional materials. One of the most significant sources of power for applications in numerous industries is provided by fuel cells. In this study, a proton exchange membrane (PEM) was developed using ethylene tetrafluoroethylene (ETFE) film with binary blends of acrylic acid (AA) and sodium styrene sulfonate (SSS), while NaCl served as an additive. As the monomer concentration increased, the degree of grafting (DG) increased. Gravimetric analyses, Fourier Transform Infrared (FTIR) spectroscopy, mechanical characteristics, and surface morphology (SEM) have all supported the radiation grafting. The physical and chemical durability of 60% DG of ETFE-g-AA-SSS film made it an ideal PEM for this study since it is more durable than other grafted samples of ETFE-g-AA-SSS film. The 60% DG of PEM's ion-exchange capacity (IEC) was determined to be 0.26 mmol g-1. They demonstrated excellent thermal, mechanical, and acid stability characteristics. In H2O2 solutions, they are highly stable, and they display significant water uptake. It is therefore applicable to acidic fuel cells.
Book Review: Advanced Technologies for Solid, Liquid, and Gas Waste Treatment
Authors: Yurekli Y.
Published: November 2023

There is an urgent need to develop effective ways to efficiently recycle the world's limited resources in the solid, liquid and gaseous phases to achieve sustainability. This could be achieved in accordance with allowable effluent standards, economic considerations and long service life through either single units or hybrid (integrated) units. In this regard, this book is a valuable resource for both academic and industrial researchers, bringing together the latest developments in compost, advanced oxidation, reactive membrane, adsorptive, electrocoagulative, and pyrolytic processes for the treatment of solid wastes, wastewater, and toxic gases. The strengths and weaknesses of the technologies are compared throughout the 15 chapters with extensive tabulated data from the literature and well-illustrated figures. Recommendations for the future and challenges are provided at the end of each section.
Steady Kähler–Ricci solitons on crepant resolutions of finite quotients of Cn$\mathbb {C}^n$
Authors: Biquard Olivier , Macbeth Heather
Published: November 2023

We prove the existence of steady Kähler–Ricci solitons on equivariant crepant resolutions of , where is a finite subgroup of acting freely on .
Natural languages and RNA virus evolution
Authors: Ariza‐Mateos Ascensión , Briones Carlos , Perales Celia , Sobrino Francisco , Domingo Esteban , Gómez Jordi
Published: November 2023

Information concepts from physics, mathematics and computer science support many areas of research in biology. Their focus is on objective information, which provides correlations and patterns related to objects, processes, marks and signals. In these approaches only the quantitative aspects of the meaning of the information is relevant. In other areas of biology, ‘meaningful information’, which is subjective in nature, relies on the physiology of the organism's sensory organs and on the interpretation of the perceived signals, which is then translated into action, even if this is only mental (in brained animals). Information is involved, in terms of both amount and quality. Here we contextualize and review the main theories that deal with ‘meaningful‐information’ at a molecular level from different areas of natural language research, namely biosemiotics, code‐biology, biocommunication and biohermeneutics. As this information mediates between the organism and its environment, we emphasize how such theories compare with the neo‐Darwinian treatment of genetic information, and how they project onto the rapid evolution of RNA viruses.

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The Finite Element Method in Time for Multibody Dynamics
Authors: Bauchau Olivier A.
Published: November 2023

The generalized-α scheme has become the approach of choice for the time integration of the equations of motion of multibody systems. Despite its simplicity, this scheme presents drawbacks: the time step size cannot be changed easily, making it difficult to implement time adaptivity, and the solution of periodic problems cannot be found easily. This paper explores an alternative approach based on the finite element method in time. The basic principles underpinning the approach are presented and both time-continuous and time-discontinuous approaches are investigated. Two types of Galerkin schemes will be presented here: the time-continuous and the time-discontinuous schemes. In the former, the displacement field is continuous across interelement boundaries, whereas discontinuities or “jumps” are allowed across inter-element boundaries for the latter. Simple problems are treated to identify the best schemes. Families of schemes of various accuracy are presented. The first family, based on time-continuous elements, features schemes that do not present numerical dissipation. Asymptotic annihilation is achieved by the time-discontinuous elements that form the second family. The problem of kinematic constraints is treated within the framework of the finite element method in time. Special emphasis is devoted to the satisfaction of the kinematic constraints and their time derivative within a time element.
SPIRA Coils: Soft Self-Sensing Pneumatic Integrated Retractable Actuator Coils
Authors: Greenwood Jacob R. , Felt Wyatt
Published: November 2023

This paper introduces a novel self-sensing coiled actuator called a “SPIRA Coil.” This soft pneumatic actuator is formed from thin sheets of PET plastic that are laminated into a coil shape that unfurls like a “party horn” when inflated. Many soft actuators require large pressure to create only modest strains. SPIRA Coils, in contrast, can easily be designed and fabricated to extend over dramatic distances with relatively low working pressures. In this work, some of the actuators with a coiled outer diameter of approximately 2 cm were able to extend 60 cm with less than 5 kPa. The internal structure of a SPIRA Coil is formed by two layers of metalized PET that separate in the extended portion of the actuator. Where the coiled portion of the actuator begins, the sheets come together, closing an electrical circuit. By measuring the resistance of the circuit, the extended length of the actuator can be determined. The paper presents and experimentally validates easy-to-use design models for the actuator’s self-retracting spring stiffness, its pneumatic extension force, and its internal length-sensing electrical resistance. Testing of the self-sensing capabilities demonstrated that the embedded sensor can be used repeatably and accurately to determine the actuator length, with virtually no hysteresis (R2 = 0.996).
Spring Locus Design for Gravity Balanced Mechanisms
Authors: Rubow Colin , Archuleta Tristan , Zhang Haohan
Published: November 2023

Balancing a mechanical system against gravity enables the system to be stable in all its configurations, which, in turn, allows small and inexpensive actuators to move it. A fully gravity-balanced mechanism requires its total potential energy to remain constant for all the configurations. Common techniques for gravity balancing include the use of zero free-length springs or the manipulation of the center of masses. This paper is specifically concerned with designing gravity-balanced systems using zero free-length springs such that each link employs a single spring. We present a novel graphical approach to design gravity balanced systems, referred to as the “Spring Locus”. This approach employs loci to quickly determine the attachment locations of zero free-length springs to satisfy the criterion of maintaining constant total potential energy within the system, thus achieving a fully balanced system against gravity. The advantage of this approach is that the spring parameters can be determined graphically without the use of Lagrangian mechanics, Newtonian mechanics, or computer optimizations and allows intuitive visualization of the design space. This approach is thus expected to lower the barrier for designing gravity balanced systems. We illustrate this approach through studies of general planar open-chain linkages that are articulated by revolute joints and balanced with a single spring for each link. Our theoretical analysis was verified through simulations, followed by a physical experiment. This simple graphical approach can be a useful tool for engineers and educators.
Design of Detachable Winch System for Field-Deployable Cable Driven Parallel Robot
Authors: Flores Guevara Arely , Marshall Matthew Q.
Published: November 2023

This paper describes a mobile cable driven parallel robot that can be temporarily mounted on existing structures like lamp posts or trees. Existing works have introduced various concepts for mobile cable driven parallel robots and analyzed some of their characteristics like workspace. The proposed robots require either heavy equipment like truck-mounted telescoping poles, or deformative installation techniques like using concrete anchors in existing structures. Those works ignored the design of the hardware to which the winches would be attached. The present article is the first describing the design of a winch system and its attachment method for an ultra-portable cable driven parallel robot, one that can be quickly mounted and unmounted from existing structures. A novel application for robotics is selected as a case study and relevant performance goals drive the design of a mountable cable driven parallel robot winch. The design is fabricated and shown in the field. The prototype mounts to trees in such a way that the growth of the tree is not inhibited. This is achieved by using nylon ratchet straps to affix the robot winches. This design represents an extremely low-cost and portable approach to cable driven parallel robots because no structure needs to be constructed.
Empirically Tuned Mechanical Simulation Model of 3D-Printed Biaxial Weaves
Authors: Wirth Marc , Shea Kristina
Published: November 2023

Additive manufacturing facilitates the realization of previously infeasible designs. Amongst them are 3D-printed textiles and specifically 3D-printed weaves. Textile designs can be spatially tuned in their mechanical properties by changing the pattern and material locally, when printed on a multi-material 3D printer. To inversely design weaves with desired mechanical properties, an efficient simulation of the mechanical behavior of textiles is essential. State-of-the-art textile models are predominantly set up for nonrecurring simulations. They are accurate but slow. Textile simulations designed for efficiency are seldom capable of capturing nonlinear yarn interaction effects. In this work, we propose a textile model consisting of 1D truss elements with strain and shear dependent stiffness. The truss member properties are defined individually based on the local weave design. The properties are tuned for each textile design by matching load-extension curves and sample deformations of virtual tensile tests to test data of real tensile tests. The simulation approach is validated by tuning the algorithm for two configurations and simulating three designs not previously used for tuning. The simulation can estimate the load-extension curve of all validation samples with high accuracy and shows runtimes of under 40s on an Intel Core i7-10750H for structures with more than 3500 elements. These results pave the way towards a simulation-based approach to synthesize and optimize architected 3D-printed textiles.
Comparative Analysis of Smoothed Particle Hydrodynamics (SPH) for Fluid-Structure Interaction: Computational Performance of Lagrangian SPH and Structural Modeling Strategies
Authors: Tagliafierro Bonaventura , Martínez-Estévez Iván , Capasso Salvatore , Domínguez José M. , O’Connor Joseph , Altomare Corrado , Viccione Giacomo , Crespo Alejandro J. C. , Rogers Benedict D. , Serban Radu , Negruţ Dan
Published: November 2023

In this contribution, we discuss the pros and cons of using the Smoothed Particle Hydrodynamics (SPH) method in providing support to multiphysics simulations. The Lagrangian SPH method is proposed to address a fluid-structure interaction (FSI) problem in which the response of a flexible baffle with elastic behavior is solved by using three modeling strategies: I) a dynamic structural solver of 3D bonded rigid bodies with rotations, based on a Lumped-Parameter Method (LPM); II) a non-linear Finite Element Method structural solver (FEM), based on the Euler-Bernoulli beam model; and III) a unified SPH-based for continuum mechanics based on a Total Lagrangian formulation. The present work uses the open-source code DualSPHysics as the fluid solver and different options now available in this code to represent flexible structures. The FSI simulated process starts with a gravity-driven fluid mass that hits a flexible plate experiences wide motion excursions (comparable to its length) in a relatively short time. The fluid phase is consistently solved with a weakly compressible SPH-based solver, whereas the three solution strategies are used to model the flexibility of the solid element. By discussing the the computational performance, and the solvers particle resolution sensitivity, the outcome of this research enables understanding the requirements of each software implementation to optimize the performance scalability.
Cutting and Folding Thick-Panel Miura-Ori With One DoF
Authors: Yang Jingyi , You Zhong
Published: November 2023

Miura-ori or Miura fold is a rigid foldable and flat foldable origami pattern that is tessellated by identical parallelogram facets. The parallelograms can rotate about the creases without twisting or stretching the facets. A Miura-ori demonstrates a bidirectional folding process that can transform a large thin sheet into a compact volume with a single degree of freedom (DoF). However, large gaps along the hinges or uneven surfaces in deployed states are inevitable when thick panels are used. In this paper, the authors add uniform thickness to a Miura-ori tessellation and connect the thick panels by revolute joints on either the top or the bottom facets of the panels for valley creases or mountain creases, respectively. The thick-panel assembly is then a structure with no mobility. Regular slits are made on some facets of the tessellations not only to remove the excess constraints, but also to accommodate the panel thickness during the folding process. Having made the cuts, a thick-panel assembly is demonstrated to fold into a package with one DoF. We further notice that although the slits open up during the folding process, they are closed in the deployed state of the assembly, giving two flat and continuous surfaces. The same method can also be applied to fold the derivatives of Miura-ori such as double-corrugated patterns.
Determination of a Predictive Model for Print Quality of Desktop 3D Printers While at Sea
Authors: Radcliffe Eliott J. , Seker Drew P. , Chen Eric Y. , Horne Nina N. , Hill John L.
Published: November 2023

Shipboard vibration has been identified as having the potential to cause degradation of 3D printer performance. A proposed mitigation for this effect is to actively monitor vibration of the ship deck and critical parts on the printer. A series of tests are conducted wherein a MIL-STD-810H derived shipboard vibration profile is used to excite a printer while it builds basic test specimens. Response accelerations and pass/fail data are collected from these tests to train a logistic regression model that calculates a predicted likelihood of failure. A demonstration test is used to show the capability to monitor the vibration in real-time, and display a indicator to the operator with a “red-light / green-light” criterion. Results of this demonstration are indicative that the vibration monitoring system provides a reasonable predictive ability, and motivates future testing and real-world deployment on a naval vessel.
Should I Sketch or Should I CAD? Exploring Design Representation Strategies in Design for Additive Manufacturing Tasks
Authors: Prabhu Rohan , Cass Madison
Published: November 2023

The emergence of additive manufacturing (AM) processes has resulted in the subsequent development of digital design tools and methods. These design tools and methods are intended to help designers leverage the capabilities of AM through design for AM (DfAM). The rapid advancement of these digital design tools calls for designers to rethink their use of various design representations in the design process. For example, designers can now automate concept generation through tools such as generative design, potentially reducing designers’ reliance on conceptual sketches. However, little research has explored how designers use design representations in the face of constantly evolving DfAM methods. In this research, we aim to explore this gap through an experimental study with fourth-year engineering students. Specifically, participants were given one hour to complete a DfAM task, and their use of the various design representations was assessed using eye-tracking. Their design representation strategies (e.g., transitions between different representations) were qualitatively compared between designers that generated solutions of high vs low creativity and high vs low performance. From our results, we see that designers who generate solutions of high creativity tend to spend a significant amount of time generating CAD models of their solutions, especially in the later stage of the design task. We also see that designers who generate high-performing solutions (i.e., low build time and material) tend to spend more time sketching their solutions. These findings suggest that designers must employ different design representation strategies depending on the desired outcomes (i.e., high creativity vs high performance). These results provide an essential first step toward creating a generalized framework for designers to employ different design representations when designing for AM.
Design for Implementation: A Medical Device Development Design Process
Authors: Bravo Elisa , Austin-Breneman Jesse
Published: November 2023

Innovative design solutions from the medical device industry contribute significantly to the continuous improvement in healthcare [1,2]. However, benefits from the advances made in medical devices are not always realized, as the delivery of care to patients is not always consistent with recommended care [3, 4]. Recent studies highlight the variability in adherence of evidence-based practices by healthcare providers [3, 5]. Relevant research in implementation science asserts that an intervention or treatment will not be effective without being well implemented [6]. Medical Device Design (MDD) processes give engineering teams strategies to reliably deliver higher quality healthcare by increasing the technical performance, safety, usability, and effectiveness of the device. This work presents a new method incorporating concepts from Implementation science into an MDD process in order to improve overall health outcomes. Implementation outcomes, like clinician adherence, and the device performance are related to the health outcomes of the patient population of interest. The alternate approach uses the simultaneous design of the medical device and implementation strategy to inform design decisions by optimizing a health outcome model. Results from an illustrative case study on Acute respiratory distress syndrome (ARDS) patients was used to showcase the utility of the developed approach on medical device design.
Tooth Bending Strength in the VHCF Area
Authors: Zalfen Moritz , Mevissen Dieter , Brimmers Jens , Brecher Christian
Published: November 2023

The use of gears in electrified drivetrains and aircraft turbines leads to higher operating speeds and a higher number of load cycles at the pinion. Load cycles of N > 107 in the Very High Cycle Fatigue (VHCF) area cause a decrease in the endurance strength of case-hardened steels. Furthermore, increasing speeds increase the strain rate in the tooth root, which also has an influence on the fatigue strength known from standard tests. The determination of the strain rate effect requires the evaluation of the test results regarding the statistical significance.

The aim of this report is to analyze the different influencing factors on the tooth bending strength, e.g. contour of the tooth root, gear quality, roughness etc. Test gears are measured and the results are traced back to a FE-based tooth contact analysis for the calculation of the tooth root stress. Furthermore, the uncertainties coming for the testing procedure (e.g. stair case or horizon method) are examined and the most appropriate procedure for the planned tests is selected. In the last step the tooth bending strength in the VHCF area is tested on a 3-shaft back-to-back test rig. The test results are evaluated regarding the failure mechanisms and the statistical behavior. Finally, the minimum number of tests regarding the statistical significance of the results is assessed.
On the Use of Geometric Deep Learning Towards the Evaluation of Graph-Centric Engineering Systems
Authors: Sirico Anthony , Herber Daniel R.
Published: November 2023

Many complex engineering systems can be represented in a topological form, such as graphs. This paper utilizes a machine learning technique called Geometric Deep Learning (GDL) to aid designers with challenging, graph-centric design problems. The strategy presented here is to take the graph data and apply GDL to seek the best realizable performing solution effectively and efficiently with lower computational costs. This case study used here is the synthesis of analog electrical circuits that attempt to match a specific frequency response within a particular frequency range. Previous studies utilized an enumeration technique to generate 43,249 unique undirected graphs presenting valid potential circuits. Unfortunately, determining the sizing and performance of many circuits can be too expensive. To reduce computational costs with a quantified trade-off in accuracy, the fraction of the circuit graphs and their performance are used as input data to a classification-focused GDL model. Then, the GDL model can be used to predict the remainder cheaply, thus, aiding decision-makers in the search for the best graph solutions. The results discussed in this paper show that additional graph-based features are useful, favorable total set classification accuracy of 80% in using only 10% of the graphs, and iteratively-built GDL models can further subdivide the graphs into targeted groups with medians significantly closer to the best and containing 88.2 of the top 100 best-performing graphs on average.
Fairness- and Uncertainty-Aware Data Generation for Data-Driven Design
Authors: Xie Jiarui , Zhang Chonghui , Sun Lijun , Zhao Yaoyao Fiona
Published: November 2023

The design dataset is the backbone of data-driven design. Ideally, the dataset should be fairly distributed in both shape and property spaces to efficiently explore the underlying relationship. However, the classical experimental design focuses on shape diversity and thus yields biased exploration in the property space. Recently developed methods either conduct subset selection from a large dataset or employ assumptions with severe limitations. In this paper, fairness- and uncertainty-aware data generation (FairGen) is proposed to actively detect and generate missing properties starting from a small dataset. At each iteration, its coverage module computes the data coverage to guide the selection of the target properties. The uncertainty module ensures that the generative model can make certain and thus accurate shape predictions. Integrating the two modules, Bayesian optimization determines the target properties, which are thereafter fed into the generative model to predict the associated shapes. The new designs, whose properties are analyzed by simulation, are added to the design dataset. An S-slot design dataset case study was implemented to demonstrate the efficiency of FairGen in auxetic structural design. Compared with grid and randomized sampling, FairGen increased the coverage score at twice the speed and significantly expanded the sampled region in the property space. As a result, the generative models trained with FairGen-generated datasets showed consistent and significant reductions in mean absolute errors.
The Kinematic Synthesis of a Spherical Mechanism for Assisting in Wrist Pronation and Supination
Authors: Trotobas Clément , Azevedo Christine , Murray Andrew P.
Published: November 2023

Full use of the upper limb is necessary to carry out most tasks of daily life. Upper limb deficiencies, whether through complete or incomplete paralysis, inevitably lead to a loss of autonomy. Assistive orthoses are a potential method for restoring some autonomy. Pronation and supination, the turning of the wrist relative to the elbow, receives less focus than other joint movements in the arm. First, the utility of this degree-of-freedom in the arm is less obvious. Second, when compared to flexion and extension of the elbow, wrist prono-supination has no clear center of rotation due to the combined movement of the ulna and the radius bones as they cross and uncross in the forearm. This paper presents initial work in the design of a mechanism for a portable assistive orthosis that is expected to include powered prono-supination. The component proposed in this work is based on a spherical mechanism architecture. The capacity of these mechanisms to have a hollow center and to produce paths that follow arcs on spheres make them worth consideration in this application. A MATLAB optimization was used to perform path generation of a single spherical four-bar with the intent of replicating it three times to create the device proposed in this work. The concept was modeled in SOLIDWORKS and printed to gauge its potential.
Approximate Motion Synthesis of Four-Bar Linkages Using Poles: A Bi-Invariant Approach
Authors: Xu Tianze , Myszka David H. , Murray Andrew P.
Published: November 2023

This paper presents a technique for the approximate motion synthesis of planar four-bar mechanisms based exclusively on the locations of displacement poles. Approximation motion synthesis is the same as motion generation or rigid-body guidance except that the mechanism cannot be synthesized to meet all of the kinematic constraints and a best-fit solution must be determined. One challenge in approximate motion guidance methods is that metrics are introduced to identify the best-fit displacement and orientation angle. Thus, the optimal solution provides a match between the task positions and positions generated by the resulting linkage that is conditional on the function used to combine the displacement and orientation. Such solutions are said to lack bi-invariance as a change in reference for the problem changes the values of the metric and, hence, the mechanism.

This work focuses on the locations of the displacement poles, which are sufficient to characterize the relative task positions. Further, the displacement poles are described solely by their locations. The optimization minimizes the distance between the poles of the task positions and the poles of the positions generated by a synthesized linkage. Further, a technique is presented that does not use the entire set of displacement poles, thereby reducing the size of the optimization. The advantage of the method is that the exclusive use of pole locations results in a bi-invariant statement of the problem. The technique is illustrated with several examples and compared to other established methods.
Design and System Identification of an Actuation-Coordinated Mobile Parallel Robot with Hybrid Mobile and Manipulation Motion
Authors: Lin Han , Luo Jiayu , Huang Xiaotong , Yang Haoguang , Fu Jiaming , Voyles Richard M. , Gan Dongming
Published: November 2023

This paper presents the development of a novel Actuation-Coordinated Mobile Parallel Robot (ACMPR), with a focus on studying the kinematics of the mobile parallel robot with three limbs (3-mPRS) comprising mobile prismatic joint-revolute joint-spherical joint. The objective of this research is to explore the feasibility and potential of utilizing omnidirectional mobile robots to construct a parallel mechanism with a mobile platform. To this end, a prototype of the 3-mPRS is built, and several experiments are conducted to identify the proposed kinematic parameters. The system identification of the 3-mPRS mobile parallel mechanism is conducted by analyzing the actuation inputs from the three mobile base robots. To track the motion of the robot, external devices such as the Vicon Camera are employed, and the data is fed through ROS. The collected data is processed based on the geometric properties, CAD design, and established kinematic equations in MATLAB, and the results are analyzed to evaluate the accuracy and effectiveness of the proposed calibration methods. The experiment results fall within the error range of the proposed calibration methods, indicating the successful identification of the system parameters. The differences between the measured values and the calculated values are further utilized to calibrate the 3-mPRS to better suit the experiment environment.
Layer-to-Layer Thermal History Prediction for Thin Walls in Metal Additive Manufacturing
Authors: Tang Yifan , Bakrani Balani Shahriar , Dhalpe Akshay , Rahmani Dehaghani Mostafa , Panicker Suraj , Coatanea Eric , Wu Di , Wang G. Gary
Published: November 2023

Thermal history has a great effect on the part properties in metal additive manufacturing such as tensile strength and hardness. To study and control the thermal behavior of the AM processes, various data-driven thermal history modeling methods have been developed and tested on simulation data. However, their in-situ application scenarios are rarely explored and discussed. This paper aims to provide a layer-to-layer thermal history prediction model, which enables predicting the thermal history of a yet-to-print layer based on the data measured from the printed lower layers. First, the thermal behavior is analyzed to reveal the similarities in temperature curves of two successive layers. Then four input variables are identified, including the deposition rate, the relative height of the layer, the printing time, and the dwell time of one layer. Based on the selected input variables and the temperature output, a fully connected neural network with residual connection is designed to simplify the training process. Five numerical simulations are designed to collect temperature curves (curve segments of a temperature profile) on each layer, and one experimental study on wire arc additive manufacturing is completed to record the temperature curves. Based on the collected data, three cases are proposed to test the modeling framework, such as (a) dividing all simulation data into the training set and validation set, (b) training the model based on four simulation runs and its validation with the last simulation, and (c) training the model with all simulation data and testing on the experimental data. The former two cases show great prediction accuracies with a relative error of less than 5% in most cases, which indicates its potential in online prediction when trained with data from the same input conditions or same systems. While the applicability of the model trained only with simulation data should be explored further in real experiments.
Heuristics for Solver-Aware Systems Architecting (SASA): A Reinforcement Learning Approach
Authors: Gadi Vikranth S. , Topcu Taylan G. , Szajnfarber Zoe , Panchal Jitesh H.
Published: November 2023

The crowdsourcing literature has shown that domain experts are not always the best solvers for complex system design problems. Novices and specialists in adjacent domains can, under certain conditions, provide novel solutions at lower costs. Additionally, the best types of solvers for different sub-problems are dependent on the architecture of complex systems. The assignment of solvers based on the architecture, referred to as Solver-Aware System Architecting (SASA), expands traditional system architecting practices by considering solver characteristics and contractual incentive mechanisms in the design process and aims to improve complex system design and innovation by leveraging the strengths of domain experts, crowds, and specialists for different parts of the problem. Given the complexity of system design problems and the variety of solvers available, it is desirable to have heuristics to guide solver assignment to different problems. Developing effective heuristics for solver assignments in complex system design is challenging due to a large number of possible combinations of problem-solver pairs. To address this challenge, this paper presents a computational approach using a multi-armed bandit (MAB) formulation to generate heuristics for solver assignment. The approach is demonstrated using a simple and idealized problem of golf, which has characteristics similar to design problems, including how the problem is decomposed into sub-problems, and solved by different solvers. The results show that the proposed approach is effective in deriving a rich set of heuristics for the golf problem, and can be extended in the future to more complex systems design problems.
Multi-Agent Bayesian Optimization for Unknown Design Space Exploration
Authors: Chen Siyu , Bayrak Alparslan Emrah , Sha Zhenghui
Published: November 2023

This paper proposes a multi-agent Bayesian optimization (MABO) framework as a reference model for rational design teams to study the effects of information exchange on a team’s search performance in finding global optimum of complex objective functions with many local optima. The core idea of the framework has three main steps. First, the design space is divided into regions based on the number of agents involved in the search. In each region, only one agent works on the part of the objective function. Second, a global-local communication strategy is developed to allow agents in local searches to share their sampled design points with a global evaluator. The global evaluator computes the posterior mean and variance based on all sampled points from local agents and evaluates the acquisition function (e.g., the expected improvement) to recommend the next sampling decisions for local agents. Third, when making the decision about where to sample next, each local agent only has access to the expected improvement evaluated in its local region and chooses the design that yields the largest value locally. To evaluate how the information exchange between agents and between local and global impact the search results, our framework is compared with a multi-agent model that does not allow information sharing and global-local interaction. Furthermore, we evaluated the performance of the model based on benchmark functions with varying complexities and also investigated the impact of the number of agents on search performance. We observe that when information sharing is allowed and global-local interaction is enabled in all scenarios, there is a significant improvement in convergence speed as well as the success rate of convergence.