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Internal limiting membrane (ILM) peeling requires a delicate handling technique. It is also important that ophthalmologists can use the ILM forceps handle of their preference. This study objectively and subjectively evaluated the handling of the novel Finesse Reflex Handle (Reflex) in comparison with that of a conventional handle. The force required to close the forceps tips, evaluated using a digital force gauge, was significantly lesser for Reflex than for the conventional handle (3.14 ± 0.09 N vs. 3.84 ± 0.06 N, P < 0.001). Twenty-one ophthalmologists with various levels of experience answered a questionnaire after using both handles, and the total questionnaire score for Reflex was higher than that for the conventional handle (35.0 ± 3.7 vs. 30.0 ± 6.9, P = 0.01). Furthermore, the duration of experience as an ophthalmologist was negatively correlated with the vertical motion, assessed by video analysis, for the conventional handle (P = 0.02, r = − 0.50) but not for Reflex (P = 0.26). In conclusion, objective and subjective analyses revealed that compared with the conventional handle, the novel Reflex handle had more favourable handling characteristics. Most ophthalmologists preferred the handling of Reflex. Reflex may compensate for a lack of surgical experience. [ABSTRACT FROM AUTHOR]

Knowledge of public opinion is key to understanding citizens' attitudes towards environmental policies. However, large polls and surveys generate complex datasets from which it is not always easy to draw conclusions. In addition, tailor-made solutions for analysing public opinion face the challenge of handling too many layers of information, which can easily lead to an overwhelming user experience and impair decision-making. Service design methodologies can support the design of ad hoc visualisation tools focused on user needs. We present Op-e-nion, a case study of a visualisation tool for the analysis of public opinion regarding environmental issues, aimed at administrations and public institutions. The involvement of experts from different fields allowed for the identification of the main metrics necessary to target the least engaged socio-demographic groups as well as the barriers that limited their environmental actions. Experts also highlighted useful aspects of the design process and the final prototype to help them define more effective campaigns and policies to address social challenges and promote citizen action. An innovative step was introduced in the methodology by involving non-state actors in the evaluation of the tool, ensuring problem detection and enhancing the sustainability of the final product. Important aspects for the visualisation of multi-categorical data included simplifying the interaction with the tool while prioritising relevant information, and using highly customizable visualisations to answer specific user requirements and changing needs (i.e. analytical vs. managerial tasks). Improved visualisations of public opinion data will, in turn, better support the development of policies shaped by citizens' concerns. [ABSTRACT FROM AUTHOR]

Over the past decades, robotic automation has expanded in numerous industrial sectors; however, manufacturing operations involving the manipulation of non-rigid products are mostly preserved manual. The dynamic distortion of flexible objects underlines limitations in robot cognition and dexterity. Inspired by the gaps in composites industry automation, this paper presents a novel multifunctional robot end-effector for the robotic automation of composites layup. Aiming a holistic confrontation of layup challenges, the proposed end-effector incorporates tools for (a) the manipulation of sheet materials, like composite fabrics of variable dimensions; (b) the grasping of core materials, like foam blocks; (c) the handling of peripheral tools; (d) the exertion of fitting forces; and (e) the application of resin in diverse mold geometry cavities. The meticulous design of the end-effector's configuration allows for consistent and collision-free tool usage with no excess robot tool changes, granting even higher productivity and efficiency. The enhancement in robot dexterity and proficiency for layup operations is validated within an automotive case, where semi-automation is intended for the improvement in overall workstation's efficiency, quality, ergonomics, and well-being. [ABSTRACT FROM AUTHOR]

Learning analytics (LA) has gained increasing attention for its potential to improve different educational aspects (e.g., students' performance and teaching practice). The existing literature identified some factors that are associated with the adoption of LA in higher education, such as stakeholder engagement and transparency in data use. The broad literature on information systems also emphasizes the importance of trust as a critical predictor of technology adoption. However, the extent to which trust plays a role in the adoption of LA in higher education has not been examined in detail in previous research. To fill this literature gap, we conducted a mixed method (survey and interviews) study aimed to explore how much teaching staff trust LA stakeholders (e.g., higher education institutions or third-parties) and LA technology, as well as the trust factors that could hinder or enable adoption of LA. The findings show that the teaching staff had a high level of trust in the competence of higher education institutions and the usefulness of LA; however, the teaching staff had a low level of trust in third parties that are involved in LA (e.g., external technology vendors) in terms of handling privacy and ethics-related issues. They also had a low level of trust in data accuracy due to issues such as outdated data and lack of data governance. The findings have strategic implications for institutional leaders and third parties in the adoption of LA by providing recommendations to increase trust, such as, improving data accuracy, developing policies for data sharing and ownership, enhancing the consent-seeking process, and establishing data governance guidelines. Therefore, this study contributes to the literature on the adoption of LA in HEIs by integrating trust factors. [ABSTRACT FROM AUTHOR]

Since almost the onset of computer-supported cooperative work (CSCW), the community has been concerned with how expertise sharing can be supported in different settings. Here, the complex handling of machines based on experience and knowledge is increasingly becoming a challenge. In our study, we investigated expertise sharing in a medium-sized manufacturing company in an effort to support the fostering of hardware-based expertise sharing by using augmented reality (AR) to 'retrofit' machines. We, therefore, conducted a preliminary empirical study to understand how expertise is shared in practice and what current support is available. Based on the findings, we derived design challenges and implications for the design of AR systems in manufacturing settings. The main challenges, we found, had to do with existing socio-technical infrastructure and the contextual nature of expertise. We implemented a HoloLens application called RetrofittAR that supports learning on the production machine during actual use. We evaluated the system during the company's actual production process. The results show which data types are necessary to support expertise sharing and how our design supports the retrofitting of old machines. We contribute to the current state of research in two ways. First, we present the knowledge-intensive practice of operating older production machines through novel AR interfaces. Second, we outline how retrofitting measures with new visualisation technologies can support knowledge-intensive production processes. [ABSTRACT FROM AUTHOR]

Background: The present study presents a knowledge-based DSS framework for supporting the decision-maker and handling control decisions related to supply chains. Methods: Two binary variables were adopted for denoting at which time point a given task i starts and finishes. The scheduling issues are represented through the ontological model and appropriately interpreted using the Java environment. Regarding primary data, digital form of administration using google form platform took precedence over physical administration. Results: The findings might not be exact replication of the findings from previous studies that are limited to the influence of information and material flow on the performance of supply chain as there are concerns of what factors constitute information and material flow that need to be identified and considered. However, with the finding of associating factors of information and material flow may need to consider this in managing the flow and the supply chain. Associating factors such as information quality, information visibility, material cost, fund shortage and so on, play a role in information and material flow and the decisions made in an organization. Conclusions: Factors associating with information and material flow need to be considered in decision making as well, as the cost in any of the elements affects the flow and this would impede supply chain performance of the organization. [ABSTRACT FROM AUTHOR]

Purpose of Review: Social media has dramatically changed the access and exchange of information in healthcare and beyond. A variety of platforms and resources exist allowing blood and marrow transplant providers, researchers, and patients to interact. We review the adoption of social media by the transplantation community.Recent Findings: Social media allows on-demand access to the latest developments at national and international meetings, newly published research articles, facilitates networking with colleagues, participation in advocacy, and promoting available clinical trials. For the modern transplantation provider, the scope and ease of access to these benefits are unparalleled. Social media serves as a gateway to access relevant resources and communities for both providers and patients as it pertains to transplantation.Summary: We demonstrate the utilization and applications of social media among stem cell transplantation providers, patients, and other affiliated stakeholders. A variety of resources and communities have enhanced and increased the opportunities for engagement. [ABSTRACT FROM AUTHOR]

On the basis of the exact solutions to the non-stationary spherically symmetric Einstein and Maxwell equations for dust matter and radial electromagnetic field, a model of a wormhole with the pulsating in time inner world and two static throats has been developed. It has been shown that such a wormhole with an arbitrary radius of the Gaussian curvature can connect both two different asymptotically flat space-times and two regions of the selfsame space-time (handles of the Wheeler type). The problem of the fulfilment of the energy conditions in this wormhole has been investigated, as well as the problem of its traversability investigation has been set. [ABSTRACT FROM AUTHOR]

To simulate the behaviors of shape memory alloy (SMA) wires, several 1-D constitutive models have been proposed most of which assume a homogeneous behavior for the material. However, stress concentration caused by the grippers would lead to inhomogeneous behavior of an SMA during the tensile test. In this paper, effect of stress concentration caused by the grippers is studied on the stress-strain response of an SMA wire during tension. At first, a relation for minimum required gripping force is provided. Then the extent of influence of stress concentration is estimated, and a minimum length is proposed for the test sample of ordinary materials. Using this result and by finite element simulating the effect of stress concentration caused by grippers, a minimum length for an SMA tensile test sample is proposed. By considering this minimum length, it is possible to simulate the material behaviors neglecting the stress concentration caused by grippers and to determine material parameters with a reasonable precision using a constitutive model in which inhomogeneous behaviors are not taken into account. A simple tensile test is performed on an SMA wire whose length is more than the recommended number, and a good agreement is seen between predicted stress-strain curve based on uniform stress distribution throughout the wire and the obtained experimental results. [ABSTRACT FROM AUTHOR]

Designs of grips for flat strips made of fiber-reinforced polymers (FRPs) are put forward. They can be used for tests in tension, prestretching, and long-term loading. In order to prevent the rise of stress concentrations, special profiled grips with a varying surface curvature allowing the transmission of tensile loads to the strip by means of gradually increasing shear stresses (without peaks) have been elaborated. The results of a mathematical analysis of the stress state in the strip, an example of calculation, and experimental data obtained from testing a carbon-fiber-reinforced polymer strip in profiled model grips specially constructed for this purpose are presented. [ABSTRACT FROM AUTHOR]

An increasing number of studies are investigating the cognitive processes underlying human-object interactions. For instance, several researchers have manipulated the type of grip associated with objects in order to study the role of the objects' motor affordances in cognition. The objective of the present study was to develop norms for the types of grip employed when grasping and using objects, with a set of 296 photographs of objects. On the basis of these ratings, we computed measures of agreement to evaluate the extent to which participants agreed about the grip used to interact with these objects. We also collected ratings on the dissimilarity between the grips employed for grasping and for using objects, as well as the number of actions that can typically be performed with the objects. Our results showed grip agreements of 67 % for grasping and of 65 % for using objects. Moreover, our pattern of correlations is highly consistent with the idea that the grips for grasping and using objects represent two different motor dimensions of the objects. [ABSTRACT FROM AUTHOR]

Transferring information about object weight between hands for use in scaling prehension forces likely depends on the integrity of the structures linking the two sides of the brain. It is unknown whether healthy older adults, who demonstrate a modest decline in this connectivity, transfer fingertip force scaling for object weight between hands. In the present study, healthy older and young adults performed two tasks: gripping and lifting an object, and a ballistic finger abduction movement. For the grip and lift task, participants practiced lifting a novel object using a precision pinch grip with the right hand (RH) and then did so again with the left hand (LH). For the ballistic task, participants were trained to maximally accelerate the right index finger by abducting it. On the grip and lift task, all participants appeared to overestimate the object weight during the 1st RH lift, followed by a progressive reduction on successive lifts. This adaptation was transferred to the LH in both groups on their first lift and remained stable over subsequent lifts. In contrast, the training-induced peak abduction acceleration on the ballistic task transferred poorly to the LH in older with considerably better transfer in young adults. We conclude that the memory representations scaling the lift force for the grip and lift task generalized to the untrained hand, while the greater acceleration that was acquired during practice of the ballistic task showed an incomplete transfer to the opposite hand. These differences may indicate task-dependent interhemispheric transfer of learning in old age. [ABSTRACT FROM AUTHOR]

The shapes of our cities change very frequently. These changes have to be reflected in data sets representing urban objects. However, it must be assured that frequent updates do not affect geometric-topological consistency. This important aspect of spatial data quality guarantees essential assumptions on which users and applications of 3D city models rely: viz. that objects do not intersect, overlap or penetrate mutually, or completely cover one another. This raises the question how to guarantee that geometric-topological consistency is preserved when data sets are updated. Hence, there is a certain risk that plans and decisions which are based on these data sets are erroneous and that the tremendous efforts spent for data acquisition and updates become vain. In this paper, we solve this problem by presenting efficient transaction rules for updating 3D city models. These rules guarantee that geometric-topological consistency is preserved ( Safety) and allow for the generation of arbitrary consistent 3D city models ( Completeness). Safety as well as completeness is proven with mathematical rigor, guaranteeing the reliability of our method. Our method is applicable to 3D city models, which define-besides the terrain surface-complex spatial objects like buildings with rooms and storeys as interior structures, as well as bridges and tunnels. Those objects are represented as aggregations of solids, and their surfaces are complex from a topology point of view. 3D GIS models like CityGML, which are widely used to represent cities, provide the means to define semantics, geometry and topology, but do not address the problem of maintaining consistency. Hence, our approach complements CityGML. [ABSTRACT FROM AUTHOR]

The article presents a research study which discusses the development of a loading-constraining device to address the problem of misalignments in mechanical testing. The proposed tool features a specimen auto-alignment component which is designed to reduce bending contributions between testing machine grips. It notes that all results showed good repeatability and regularity.

The properties of a microfinger with groove patterns etched on its surface were discussed in this paper. An analytical model of the deflection was built up to study the effect of the groove size on the bending stiffness and the deflection of the grooved finger. The calculation of the analytical model is consistent with the simulation and experimental results. When the grooves depth is 0.5 μm, the spring constant of grooved microfinger is 22.8%, smaller than that of flat finger without grooved patterns. The spring constant of the finger decreases with the increasing of the depth of the grooves. A stable novel microelectric-thermal gripper is introduced based on the grooved finger. It consists of four sub-cantilever beams positioned at the diagonal lines of a square frame in the end of the main cantilever structure suspended from the silicon substrate, which guarantees an effective contact by the four-point contact area on the top surface to grab components of importance. The thermal-expansion-induced deflection makes the fingers moving vertically from an 'open' position to a working one. The grooved finger helps to decrease the bending stiffness of the finger and increase the deflection and the initial gap. The simple fabrication process has a feasibility of compatible and mass production. [ABSTRACT FROM AUTHOR]

Green coordinates require to build an enclosing cage around a shape that is deformed by manipulating the cage. In this paper, we build upon the local differences of Green coordinates and propose a method to deform a shape locally without constructing a cage. Second, we derive linear formulas to directly interpolate points on the shape to desired locations using an umbrella shaped cell. Moreover, we set up an influence region to confine the deformation in a local area. Finally, we suggest a method to automatically construct an umbrella shaped cell and thus update it consecutively while the shape is deforming. Experiments have shown that the suggested approach delivers smooth local deformations and enables shape manipulations at an interactive rate. [ABSTRACT FROM AUTHOR]

This article reports an analysis of two dimensional grasp where a convex rigid object is grasped by two contact points with friction. The purpose is to find the object orientation that minimizes the norm of the contact force vector, each element of which is composed from the normal force and friction force at each contact point. The formulation of this problem requires some equality or inequality conditions. In the analysis, the solution of the equality conditions is parameterized at first. Based on the fact that the norm of the contact force vector becomes monotonic increasing function of this parameter, the minimal parameter values are calculated by means of the piecewise analysis. Using the relation between the friction coefficient and the apex angle of the friction cone effectively, the following result is obtained: the norm of the contact force, i.e, gripping power becomes locally minimal at the object orientation where the intersection point of the upper sides of two friction cones is located in opposite direction of the gravity from the center of mass of the grasped object. [ABSTRACT FROM AUTHOR]

Abstract  The design of many thermal Microelectromechanical (MEMS) actuators is often based on finite element analysis, but lacks analytical insight. In this paper we report a novel electro-thermal microgripper and a comprehensive thermal modeling of a general 5 lineshape microbeam’s actuator using 1-D steady state heat equations. Because of the variety of microgripper fabrication technologies and their applications, different thermal boundary conditions are considered for lifted off and attached grippers. Parametric and nonparametric electrothermomechanical identification models for silicon on insulator microgripper, fabricated on 100 μm device layer, are obtained. [ABSTRACT FROM AUTHOR]

The goal of the present study was to investigate how grip forces are applied when transferring stable control of an object from one person to another. We asked how grip forces would be modified by the passer to (1) control for inertial forces as the object was transported toward the receiver and (2) control for the impending perturbation when the receiver made contact with the object. Twelve volunteers worked in pairs during this experiment. One partner, playing the role of passer, transported an object with embedded load cells forward or held the object at an interception location. The second partner, playing the role of receiver, waited at an interception location or reached toward the passed object. Kinematic results indicated that while passers performed a stereotypical movement, receivers were sensitive to the motion of the object as they reached to make contact. Grip force results indicated that passers’ grip forces and grip/load force ratios were variable on a trial-to-trial basis, suggesting that a refined internal model of the passing task was not achieved within the timeframe of the experiment. Furthermore, a decoupling of the temporal and magnitude characteristics of the grip and inertial forces was noted in conditions where passers transported the object toward the receiver. During object transfer, it was noted that passers used visual feedback-based anticipatory control to precisely time initial grip force release, while somatosensory control was used by both the passer and receiver to precisely coordinate transfer rate. [ABSTRACT FROM AUTHOR]

The tread of conventional truck tyres is subject to continuous wear during use and the tyre looses more and more of its grip. "Michelin Durable Technologies" tyres exhibit more grip up to the wear limit than conventional tyres. Michelin Durable Technologies represent a continuous innovation. Further new technologies are to follow the ones already implemented. The technologies presented so far are improvements to the tread patterns and to the architecture of truck tyres. [ABSTRACT FROM AUTHOR]

The proposed technical solution relates to testing equipment, in particular, to specimen fastening assemblies in fatigue testing machines. This is a collet-type gripping mechanism in which a tapered connection contains parts that change the type of friction and facilitate their mutual displacement. This gripping device can be used in testing machines when cylindrical specimens are loaded under cantilever and pure rotating bending. [ABSTRACT FROM AUTHOR]

The article evaluates several dental equipment and supplies from Dentsply International Inc. including the Cavitron ultrasonic scaler system, Oraqix non-injectable local anaesthetic and Flexichange silicone handles.