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1 – 10 of over 44000
Article
Publication date: 3 January 2023

Joao Vitor da Silva Moreira, Karina Rodrigues, Daniel José Lins Leal Pinheiro, Thaís Cardoso, João Luiz Vieira, Esper Cavalheiro and Jean Faber

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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.

Practical implications

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.

Social implications

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.

Originality/value

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.

Details

Journal of Enabling Technologies, vol. 17 no. 1
Type: Research Article
ISSN: 2398-6263

Keywords

Article
Publication date: 26 February 2021

Flavio Gazzani

The purpose of this paper is to examine the introduction of three specific fiscal flexible mechanisms such as VAT surcharges/discounts, surcharges on import/manufacture of risk…

Abstract

Purpose

The purpose of this paper is to examine the introduction of three specific fiscal flexible mechanisms such as VAT surcharges/discounts, surcharges on import/manufacture of risk substances and maturity land tax to implement a new environmental fiscal reform that aims to reduce pollutions and emissions and avoid a regressive impact on low-income households using a feedback system.

Design/methodology/approach

The idea behind this article is to explore alternative environmental taxation system that aims to foster the transition to social-ecological sustainability without affect negatively poor and low-income households. It looks at the potential of environmental fiscal reform in terms of environmental benefits and present in the first section, evidence of some economic regressive impact caused by environmental fiscal reform in European Union from previous empirical studies. The article then introduces of a feedback mechanism to create a repayment system, such as rebate or cash transfer to compensate the regressive effect of the levy being added to the consumer price affecting low-income households in a very short period and push consumers to buy alternative eco-friendly products and services and to stimulate the market to offer them.

Findings

Lowering VAT rate for green products and services has the potential to increase demand for sustainable products and services and stimulate green jobs. Surcharges on import and manufacture of risk substances play a significant role to discourage the import of hazardous and pollutant substances by putting price on them and push the industrial sector towards a medium and long-term transition. Lowering taxes rates for buildings in inner cities encourage improvements and renovations, while raising tax on peri-urban areas discourage land speculation in areas with higher grade of biodiversity. This fiscal mechanism indirectly will reduce private and public transport emissions caused by urban sprawling and travel costs, reduce public infrastructure costs for connecting suburban area to the inner city and reduce the loss of urban-edge farmland area that are vital for smart urban growth.

Originality/value

The previous studies on the economic impact of the on environmental fiscal reform analysis, have focused on environmental aspects, economic growth and employment, but little on the regressive impact in short and medium terms on least wealthy sections of society. The proposed feedback mechanism aims to reduce distortion and inequalities caused by surcharges on existing taxation to low-income using monetary repayment measures, especially for products and services with elastic demand and no substitutes.

Details

International Journal of Social Economics, vol. 48 no. 5
Type: Research Article
ISSN: 0306-8293

Keywords

Abstract

Details

Automated Information Retrieval: Theory and Methods
Type: Book
ISBN: 978-0-12266-170-9

Article
Publication date: 21 September 2011

Antonios Antoniou, Gregory Koutmos and Gioia Pescetto

This paper investigates the possibility that futures markets attract noise traders who engage in positive feedback trading, an especially destabilizing form of noise trading. The…

Abstract

This paper investigates the possibility that futures markets attract noise traders who engage in positive feedback trading, an especially destabilizing form of noise trading. The hypothesis is tested using data from four major national index futures markets. The empirical evidence is consistent across all index futures markets under examination. Specifically, there is significant evidence of positive feedback trading. More importantly, the feedback trading pattern exhibits significant long memory in the sense that it depends on longer lags of past prices. Because volatility is asymmetric, the implication is that feedback trading is also asymmetric, being more prevalent during down markets so that mispricing is more likely during those periods that feedback traders are more active.

Details

Review of Behavioural Finance, vol. 3 no. 2
Type: Research Article
ISSN: 1940-5979

Keywords

Article
Publication date: 4 April 2019

Zhen Shao and Hao Yin

Drawing upon institution-based trust theory, the purpose of this paper is twofold: firstly, to examine the joint influences of legally binding and market-driven institutional…

1841

Abstract

Purpose

Drawing upon institution-based trust theory, the purpose of this paper is twofold: firstly, to examine the joint influences of legally binding and market-driven institutional mechanisms in promoting customers’ trust and continuance intention in the ridesharing platform; and secondly, to examine if there exists a trust transfer mechanism between institution-based trust and interpersonal trust.

Design/methodology/approach

An online survey was conducted in China and data were collected from 307 customers in DiDi, which is one of the largest ridesharing platforms in China. Structural equation modeling statistical method was used to test the theoretical model and research hypotheses.

Findings

The empirical results suggest that market-driven institutional mechanisms, regarding feedback and surge pricing, have strong influences on customers’ trust in the ridesharing platform. In addition, legally binding institutional mechanisms, regarding payment security and driver certification, are also beneficial to promote customers’ trust. Furthermore, there is a trust transfer between customers’ trust in the platform and trust in the driver.

Practical implications

This study provides guidelines to the administrators of the ridesharing platform to establish effective institutional mechanisms. In particular, the platform can appropriately adopt and implement the legally binding mechanisms combined with market-driven mechanisms on the platform, in order to enhance customers’ trust and promote their subsequent transaction behaviors.

Originality/value

This study enriches and extends the extant literature of institution-based trust from e-commerce to the sharing economy by identifying four significant institutional mechanisms. Furthermore, this study presents a new perspective of customer trust (one-to-many) in the context of ridesharing and uncovers the transfer mechanism between institution-based trust and interpersonal trust.

Details

Internet Research, vol. 29 no. 5
Type: Research Article
ISSN: 1066-2243

Keywords

Article
Publication date: 31 August 2021

Zbigniew Rarata

The purpose of this paper is to investigate airfoil’s tonal noise reduction mechanism when deploying surface irregularities, such as surface waviness by means of spatial stability…

148

Abstract

Purpose

The purpose of this paper is to investigate airfoil’s tonal noise reduction mechanism when deploying surface irregularities, such as surface waviness by means of spatial stability analyses.

Design/methodology/approach

Flow field calculations over smooth and wavy-surface NACA 0012 airfoils at 2° angle of attack and at Reynolds number of 200,000 are performed using the large eddy simulation (LES) approach. Three geometrical configurations are considered: a smooth NACA 0012 airfoil, wavy surface on the suction side (SS) and wavy surface on the pressure side (PS). The spatial stability analyses using the LES-generated flow fields are conducted and validated against the Orr-Sommerfeld stability analysis for the smooth airfoil configuration.

Findings

The spatial stability analyses show that inclusion of the wavy-type modification on the SS of the airfoil does not lead to altering of the acoustic feedback loop mechanism, with respect to the mechanism observed for the smooth airfoil configuration. In contrast, applying the surface modifications to the airfoil PS leads to a significant reduction of the amplification range of disturbances in the vicinity of the trailing edge for the frequency of the acoustic feedback loop mechanism.

Practical implications

The spatial analyses using, for example, LES-generated flow fields can be widely used to determine acoustic sources and associated distributions of amplifications for a wide range of applications in the aeroacoustics.

Originality/value

The spatial stability analysis approach based on flow fields computed a priori using the LES method has been introduced, validated and used to determine behaviour of the acoustic feedback loop when accurate reconstruction of geometry effects is required.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 January 1990

Robert Waldersee and Fred Luthans

Through the years, positive feedbackhas been accepted as an effectivemethod of improving employeeperformance. However, recentresearch reviews question acrossindividual consistency…

Abstract

Through the years, positive feedback has been accepted as an effective method of improving employee performance. However, recent research reviews question across individual consistency of this effect. This inconsistency may arise from the interaction of feedback type (positive and negative) with individual differences. A Contingency Model of Feedback is proposed. This model integrates previous theory and research. It has implications which would allow service sector managers to select the most appropriate feedback type for each employee.

Details

Journal of Organizational Change Management, vol. 3 no. 1
Type: Research Article
ISSN: 0953-4814

Keywords

Article
Publication date: 6 March 2017

Vladislav Valentinov

The rise of the general systems theory in the twentieth century would not have been possible without the concept of feedback. Of special interest to the present paper is Niklas…

Abstract

Purpose

The rise of the general systems theory in the twentieth century would not have been possible without the concept of feedback. Of special interest to the present paper is Niklas Luhmann’s reconstruction and critique of Wiener’s cybernetic approach to the feedback concept. Luhmann has suggested that the operation of the feedback-controlled systems potentially poses problems of sustainability. The purpose of this paper is to explore this suggestion in more detail.

Design/methodology/approach

The reconstruction of the arguments of Luhmann and Wiener shows that both scholars approached the feedback concept from the “system-environment” perspective. Luhmann takes system-environment relations to be inherently precarious. Wiener underscores the importance of the sensitivity of the feedback-controlled systems to their environment.

Findings

Drawing on Norbert Wiener’s and Niklas Luhmann’s ideas, the paper shows that every specification of the feedback mechanism implies the drawing of the moral boundary that demarcates those parts of the environment to which the relevant system is sensitive from those to which it is not. A likely outcome of this boundary drawing is the maintenance of intra-systemic complexity at the cost of the deteriorating sustainability of the system in its environment.

Originality/value

Until today, the general system theory has sought to explain organized complexity and rightly underscored the role of feedback in maintaining it, thereby inadvertently creating the chasm between the complexity and sustainability dimensions of human civilization. The present paper pleads for reorienting of the systems-theoretic analysis of the feedback concept toward closing this chasm.

Details

Kybernetes, vol. 46 no. 3
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 16 June 2022

Adnan Muhammad Shah, Wazir Muhammad and KangYoon Lee

This study examines how service feedback and physician popularity affect physician demand in the context of virtual healthcare environment. Based on the signaling theory, the…

Abstract

Purpose

This study examines how service feedback and physician popularity affect physician demand in the context of virtual healthcare environment. Based on the signaling theory, the critical factor of environment uncertainty (i.e. disease risk) and its impact on physician demand is also investigated. Further, the research on the endogeneity of online reviews in healthcare is also examined in the current study.

Design/methodology/approach

A secondary data econometric analysis using 3-wave data sets of 823 physicians obtained from two PRWs (Healthgrades and Vitals) was conducted. The analysis was run using the difference-in-difference method to consider physician and website-specific effects.

Findings

The study's findings indicate that physician popularity has a stronger positive effect on physician demand compared with service feedback. Improving popularity leads to a relative increase in the number of appointments, which in turn enhance physician demand. Further, the impact of physician popularity on physician demand is positively mitigated by the disease risk.

Originality/value

The authors' research contributes to a better understanding of the signaling transmission mechanism in the online healthcare environment. Further, the findings provide practical implications for key stakeholders into how an efficient feedback and popularity mechanism can be built to enhance physician service outcomes in order to maximize the financial efficiency of physicians.

Details

Information Technology & People, vol. 36 no. 3
Type: Research Article
ISSN: 0959-3845

Keywords

Article
Publication date: 3 October 2016

Xiaodong Li, Xinshuai Guo, Chuang Wang and Shengliang Zhang

The purpose of this paper is to empirically test a research model that incorporated antecedents of praise feedback behaviour (fear of confrontation and incentive for reducing…

1870

Abstract

Purpose

The purpose of this paper is to empirically test a research model that incorporated antecedents of praise feedback behaviour (fear of confrontation and incentive for reducing nuisance costs), praise feedback behaviour (deliberatively praise feedback, casual praise feedback, and true compliment feedback) and consequences (trust and repurchase intention).

Design/methodology/approach

A structural equation model was employed to test the relationships of the research model using survey data collected from 398 Taobao consumers.

Findings

The results showed that fear of confrontation and incentive for reducing nuisance costs had a significant positive influence on deliberatively praise feedback and true compliment feedback, respectively, and both antecedents had a significant positive influence on casual praise feedback of consumers. It also showed that trust was influenced negatively by deliberatively praise feedback, and positively by casual praise feedback and true compliment feedback. Meanwhile, deliberatively praise feedback and true compliment feedback were found to have negative and positive influences on repurchase intention, respectively.

Originality/value

This research was a pilot study to identify a three-dimension conceptualization of praise feedback behaviour from the perspective of customer satisfaction, and to understand positive review bias from the perspective of input processes.

Details

Internet Research, vol. 26 no. 5
Type: Research Article
ISSN: 1066-2243

Keywords

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