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The purpose of this paper is to investigate the impact of system-generated visual feedback and continued contribution on individuals’ motivation to share knowledge in a crowdsourcing environment.

An experimental setting was designed to investigate participants’ motivation to contribute knowledge in a crowdsourcing environment. Responses from a total of 101 participants were analyzed. The independent variables were visual feedback and time. The dependent variable was the participants’ self-expressed willingness to further contribute in the experimental knowledge-sharing activity.

A significant main effect of time was found, showing overall gains in the mean willingness to participate over time. It was also found that the mean willingness of the control and top assimilation groups were higher than the mean willingness of the rank contrast and status groups. The mean difference obtained for the control group was mainly during the first half of the knowledge-sharing tasks, while the mean difference obtained for the top assimilation group was mainly during the second half of the knowledge-sharing tasks.

This study contributes to the literature related to motivation in knowledge sharing by providing theory-based, empirical evidence of the potential for external interventions to improve willingness to contribute and sustain knowledge sharing. The findings additionally provide practical implications for motivating and sustaining knowledge sharing.

One of the main causes of long-term prosthetic abandonment is the lack of ownership over the prosthesis, which was caused mainly by the absence of sensory information regarding the lost limb. The period where the patient learns how to interact with a prosthetic device is critical in rehabilitation. This ideally happens within the first months after amputation, which is also a period associated with the consolidation of brain changes. Different studies have shown that the introduction of feedback mechanisms can be crucial to bypass the lack of sensorial information. To develop a biofeedback system for the rehabilitation of transfemoral amputees – controlled via electromyographic (EMG) activity from the leg muscles – that can provide real-time visual and/or vibratory feedback for the user.

The system uses surface EMG to control two feedback mechanisms, which are the knee joint of a prosthetic leg of a humanoid avatar in a virtual reality (VR) environment (visual feedback) and a matrix of 16 vibrotactile actuators placed in the back of the user (vibratory feedback). Data acquisition was inside a Faraday Cage using an OpenEphys® acquisition board for the surface EMG recordings. The tasks were performed on able-bodied participants, with no amputation, and for this, the dominant leg of the user was immobilized using an orthopedic boot fixed on the chair, allowing only isometric contractions of target muscles, according to the Surface EMG for Non-Invasive Assessment of Muscles (SENIAM) standard. The authors test the effectiveness of combining vibratory and visual feedback and how task difficulty affects overall performance.

The authors' results show no negative interference combining both feedback modalities and that performance peaked at the intermediate difficulty. These results provide powerful insights of what can be accomplished with the population of amputee people. By using this biofeedback system, the authors expect to engage another sensory modality in the process of spatial representation of a virtual leg, bypassing the lack of information associated with the disruption of afferent pathways following amputation.

The authors developed a showcase with a new protocol and feedback mechanisms showing the protocol's safety, efficiency and reliability. However, since this system is designed for patients with leg amputation, the full extent of the effects of the biofeedback training can only be assessed after the evaluation with the amputees, and the results obtained so far establish a safe and operational protocol to accomplish this.

In this study, the authors proposed a new biofeedback device intended to be used in the preprosthetic rehabilitation phase for people with transfemoral amputation. With this new system, the authors propose a mechanism to bypass the lack of sensory information from a virtual prosthesis and help to assimilate visual and vibrotactile stimuli as a cue for movement representation.

With this new system, the authors propose a mechanism to bypass the lack of sensory information from a virtual prosthesis and help to assimilate visual and vibrotactile stimuli as a cue for movement representation.

The authors' results show that all users were capable of recognizing both feedback modalities, both separate and combined, being able to respond accordingly throughout the tasks. The authors also show that for a one-session protocol, the last difficulty level imposed a greater challenge for most users, explained by the significant drop in performance disregarding the feedback modality. Lastly, the authors believe this paradigm can provide a better process for the embodiment of prosthetic devices, fulfilling the lack of sensory information for the users.

It is widely agreed that amputees have to rely on visual input to monitor and control the position of the prosthesis while reaching and grasping because of the lack of proprioceptive feedback. Therefore, visual information has been a prerequisite for prosthetic hand biofeedback studies. This is why, the underlying characteristics of other artificial feedback methods used to this day, such as auditive, electro‐tactile, or vibro‐tactile feedback, has not been clearly explored. The purpose of this paper is to explore whether it is possible to use audio feedback alone to convey more than one independent variable (multichannel) simultaneously, without relying on the vision, to improve the learning of a new perceptions, in this case, to learn and understand the artificial proprioception of a prosthetic hand while reaching.

Experiments are conducted to determine whether the audio signals could be used as a multi‐variable dynamical sensory substitution in reaching movements without relying on the visual input. Two different groups are tested, the first one uses only audio information and the second one uses only visual information to convey computer‐simulated trajectories of two fingers.

The results show that it is possible to use auditive feedback to convey artificial proprioceptive information instead of vision as a guide, thus assist users by internalizing new perceptions.

This way, the strong and weak points of auditive feedback can be observed and can be used to improve future feedback systems or schemes, which can integrate different feedback methods to provide more information to the user.

The implementation of interaction design concepts to facilitate communication between users and shopping websites has gained increasing attention in recent years. Mouse hover is a vital interaction method for users to access shopping sites and significantly impacts their decision-making experience. A well-designed mouse hover function can effectively enhance the user's search performance and improve the user experience. The purpose of this study is to investigate whether the dynamic prompt designs at the hover position and the degree of feedback transparency may affect the user's task performance and personal feelings when operating the hover function on the shopping website.

The study employed two independent variables in the experiments: dynamic prompt and background transparency of hover feedback. A between-subject design of 2 (single flicker and continuous flicker) × 3 (transparency at 0%, 25%, and 50%) was adopted in the experiment. A total of 60 participants were invited to participate in the experiment using the purposive sampling method. Participants were asked to complete four operation tasks, and the time of each was recorded. They were then asked to complete the system usability scale (SUS) questionnaire and conduct subjective evaluations before they were briefly interviewed.

The generated results revealed that: (1) In the interaction with a shopping website, the degree of background transparency of hover feedback affected the participants' task performance. (2) The effect of a single flicker had significantly higher subjective evaluation results regarding the degree of rationality compared with a continuous flicker. (3) The participants' perceptions of the information clarity were affected when the background transparency of hover feedback was 50%. (4) The effect of a continuous flicker was better than that of a single flicker when the background transparency of hover feedback was 25%. The participants' attraction to a continuous flicker was significantly higher than that of a single flicker. Nonetheless, when the degree of background transparency was at 0% or 50%, the results were the opposite.

The findings generated from the research can be a reference for the development of hover operation in the user interface design for shopping websites.

In this paper the aim is to present Debate Dashboard, an online collaborative platform designed to support distributed knowledge management and decision making. The platform integrates an argument mapping tool with visual widgets with the objective of enhancing collective sense‐making and mutual understanding as well as to compensate for the costs of mediated communication in virtual collaborative environments.

The design of Debate Dashboard is based on the theory of common ground according to which participants involved in a conversation build mutual understanding thanks to the exchange of different types of feedback. Using the concept of grounding cost, the authors identified several features of the Dashboard supposed to favour mutual understanding and knowledge sharing. Such features have been implemented through six visual widgets selected through a benchmarking of currently available visualization tools.

The paper discusses the limitations and advantages of online argumentation to support online discussions and presents a review of current visualization tools. The design of a new platform able to integrate online argumentation and visualization technologies is described and it is argued that Debate Dashboard will improve online collaboration in many respects especially in terms of supporting the construction of shared knowledge representations for geographically distributed collaborative teams.

First, the work adds to the debate on the development of online argumentation platforms by offering an alternative theoretical perspective based on language and conversational studies. Second, it proposes for the first time to integrate argumentation and visualization technologies in the same tool to create an augmented collaborative platform able to overcome the limitations of both traditional online collaboration technologies, such as forums and wikis, as well as the criticalities associated with the use of argumentation technologies.

Teleoperated minimally invasive surgical robots can significantly enhance a surgeon's accuracy, dexterity and visualization. However, current commercially available systems do not include significant haptic (force and tactile) feedback to the operator. This paper describes experiments to characterize this problem, as well as several methods to provide haptic feedback in order to improve surgeon's performance. There exist a variety of sensing and control methods that enable haptic feedback, although a number of practical considerations, e.g. cost, complexity and biocompatibility, present significant challenges. The ability of teleoperated robot‐assisted surgical systems to measure and display haptic information leads to a number of additional exciting clinical and scientific opportunities, such as active operator assistance through “virtual fixtures” and the automatic acquisition of tissue properties.

Robonaut is a humanoid robot designed by the Robotic Systems Technology Branch at NASA's Johnson Space Center in a collaborative effort with Defense Advanced Research Projects Agency. This paper describes the implementation of haptic feedback into Robonaut and Robosim, the computer simulation of Robotonaut. In the first experiment, we measured the effects of varying feedback to a teleoperator during a handrail grasp task. Second, we conducted a teleoperated task, inserting a flexible beam into an instrumented receptacle. In the third experiment, we used Robonaut to perform a two‐arm task where a compliant ball was translated in the robot's workspace. The experimental results are encouraging as the Dexterous Robotics Lab continues to implement force feedback into its teleoperator hardware architecture.

This quasi-experimental study examined the effectiveness of audio-visual and written feedback (AVF + WF) on undergraduate students versus only receiving WF in the context of an English as a Foreign Language (EFL) online classroom during the coronavirus disease 2019 (COVID-19) lockdown.

The study used the estimator Difference in Difference (DID) to compare a treated and control group in a pre-and post-test under the application of six treatment sessions, plus a student's perception survey at the end of the treatment. The treated group that received the multimodal feedback showed higher improvement rates in the paragraph content between the first and final drafts than students in the control group.

Results indicated that receiving a combination of AVF + WF had a statistically significant effect on mechanics (p < 0.001) and the use of transition words (p = 0.003).

These findings will benefit educational agents, professors and stakeholders for social and economic development.

While previous studies have only used student perceptions of the feedback, this study contributes with empirical data through quasi-experimental analysis and measures the effectiveness of feedback in online learning environments.

The majority of research on energy feedback has been conducted in residential households; in this study, the authors aim to examine the effectiveness of similar initiatives in a college environment. The our goal was to see how much additional electricity savings could be induced using feedback beyond average savings achieved by goal-setting and to provide students information on how to conserve.

All participants set goals related to personal environmental behavior and received electricity-saving tips. Half of the participants were exposed to real-time, group-level, ambient and direct feedback of electric use for their dormitory floor through an iPad display. The control group received no feedback.

The group that received the real-time feedback reduced its consumption, whereas the control group did not. The feedback group’s change in consumption was significantly greater than the control group’s. The results are discussed in the context of injunctive norms, reminders, ambient feedback and numerical feedback, as well as the theory of planned behavior.

Further research could test for long-term effects, whether the interventions applied in this study would be effective in other university contexts and whether the interventions would influence other environmental habits apart from electricity consumption on campuses.

This is one of the first energy feedback studies to demonstrate the effectiveness of group-level data, let alone specifically in a college dormitory and has implications for influencing conservation behavior of residential college students worldwide.

This paper aims to improve the performance of a two-camera robotic feedback system designed for automatic pick and place application by modifying its velocity profile during switching of control.

Cooperation of global and local vision sensors ensures visibility of the target for a two-camera robotic system. The master camera, monitoring the workspace, guides the robot such that image-based visual servoing (IBVS) by the eye-in-hand camera transcends its inherent shortcomings. A hybrid control law steers the robot until the system switches to IBVS in a region proven for its asymptotic stability and convergence through a qualitative overview of the scheme. Complementary gain factors can ensure a smooth transition in velocity during switching considering the versatility and range of the workspace.

The proposed strategy is verified through simulation studies and implemented on a 6-DOF industrial robot ABB IRB 1200 to validate the practicality of adaptive gain approach while switching in a hybrid visual feedback system. This approach can be extended to any control problem with uneven switching surfaces or coarse/fine controllers which are subjected to discrete time events.

In complex workspace where robots operate in parallel with other robots/humans and share workspaces, the supervisory control scheme ensures convergence. This study proves that hybrid control laws are more effective than conventional approaches in unstructured environments and visibility constraints can be overcome by the integration of multiple vision sensors.

The supervisory control is designed to combine the visual feedback data from eye-in-hand and eye-to-hand sensors. A gain adaptive approach smoothens the velocity characteristics of the end-effector while switching the control from master camera to the end-effector camera.