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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.

This paper aims to present the proposition of a new experimental method for obtaining very crucial data of the structural steel that is used in the tank of oil filled power transformers, namely, the volumetric losses and the magnetic permeability, both in function of the density of magnetic flux. Although these data are not usually available, they are fundamental for helping the transformer designer in avoiding the occurrence of hot spots in the transformer tank. The adoption of a conventional Epstein frame has restrictions because of the incompatibility between it and the samples of the steel.

The basis of the proposition is the same as that of the Epstein frame, with significant attention paid to the additional losses in the winding that creates the magnetic flux to the samples in the core. These losses can be significant and are created by the harmonics of current along the windings and are summed to the ohmic losses. For separating these winding losses from the magnetic losses, each sample is made as being the core of a toroidal 1:1 transformer. Thus, two tests with two identic of these toroidal transformers are necessary.

The proposed methodology is simple, because it is very similar to the classical tests of transformers (no-load and short-circuit tests). The process of separation of losses requires only a numerical fitting of curves for adjusting the winding losses as a function of the current amplitude, and the obtained results are coherent with the expected behavior of the magnetic losses and the magnetic permeability of a structural steel.

The method gives very approximate results in comparison to those obtained using the Epstein frame. The influences of the temperature and/or of the skin effect have not been evaluated.

Practical, real and thus confident data of structural steel, such as the magnetic permeability and the volumetric losses (hysteresis and Foucault), become available for the transformer designer to take actions for not only reducing the tank losses but also for avoiding the occurrence of hot spots through computer simulation.

The proposition is very new, as it allows to test steel samples with a size that does not fit to a usual Epstein frame. It takes into account the real influence of harmonic of currents in the losses along the winding of a classical Epstein frame, which has not been so far mentioned. It allows obtaining data of structural steel that had not been considered important until now.

The application of the Internet to traditional business and administrative activities has introduced considerable digitisation and process automation. One key area of development from a research perspective is the use of electronic (e‐)surveys, based on Internet technology. E‐surveys can bring many benefits from a research perspective, including extremely low marginal costs, automation of processes, and the ability to collect and manage very large samples. However, experience in the use of e‐surveys has found considerable challenges in achieving a quality sample frame and response rates. This paper explores the development of an e‐survey tool for assessing information needs of growth enterprises in Brazil. A key learning from the use of the survey is the use of control methods for both improving the response rate, and, as a consequence, the sample frame.

Sustainability at the corporate level is interpreted as the approach capable of creating prosperity over long-term horizons through targeted strategic integration, sustainable business system and societal transitions, beyond economic growth, along with environmental quality and social equity. In this context, this article aims to explore the interplay of the relationship between environmental innovation and corporate sustainability.

A systematic literature review (SLR) was conducted in the Web of Science and Scopus databases for the last six decades to explore the proposed relationship. Data were selected on August 2, 2020, and the analysis period lasted until July 20, 2021. A research protocol consistent with the methodological rigor required in conducting an SLR was prepared for the mapping and analysis of relevant research.

In the last five years, there has been an evolution in research related to green innovation in supply chain management. Based on this evolution, there is a growing concern with the development of sustainable business models, taking into account the motivation to adopt green innovation practices aimed at corporate image. The purpose lies in verifying the organizational capabilities in achieving corporate sustainability practices and economic performance. The results show a greater concentration of studies exploring (1) sustainable business models, (2) the complexity of the sustainability tripod balance, in addition to (3) organizational strategies based on green and competitive practices.

Few works explored the context of small and medium-sized companies, especially those located in emerging and underdeveloped countries. This opens up a promising field of research. The main contributions of this article are related to (1) the presentation of a portfolio of theoretical and methodological approaches on the subject, which allows the exploration of the possibilities of empirical studies; and (2) showing the current status of research on environmental innovation and its impact on corporate sustainability. This article explores the interplay of the relationship between environmental innovation and corporate sustainability and brings state-of-the-art research about the theme.

This study aims to identify the social representation of cloud computing from the perspective of Information Technology (IT) professionals in emerging countries, comparing it with the extant literature on this subject.

Data were collected from IT professionals in Brazil, which was used as a proxy for the emerging countries’ context related to cloud computing. Social Representation Theory was then applied to analyze the data.

Mismatches between theory and practice on cloud computing make it clear that most of the current scientific literature on cloud computing is, to a great extent, based on the context of developed countries rather than on the context of emerging ones.

Errors of inference may have been made during the categorization of the words evoked. Furthermore, Brazil was used as a proxy for the emerging countries’ context related to cloud computing.

IT professionals in emerging countries have quite an operational view of cloud computing. Thus, companies in these countries have to align cloud computing better with new business models and corporate strategies in order to take advantage of the transformational impacts of cloud computing.

IT professionals in emerging countries have failed to notice the strategic value of cloud computing, the new business models enabled by same, the privacy issues related to it and the impact cloud computing adoption can have on the IT costs of an organization. Moreover, mobility can be a paramount issue related to cloud computing in emerging countries – a fact thus far overlooked by academia.