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This paper proposes a novel method for human hands tracking using data from an event camera. The event camera detects changes in brightness, measuring motion, with low latency, no motion blur, low power consumption and high dynamic range. Captured frames are analysed using lightweight algorithms reporting three-dimensional (3D) hand position data. The chosen pick-and-place scenario serves as an example input for collaborative human–robot interactions and in obstacle avoidance for human–robot safety applications.

Events data are pre-processed into intensity frames. The regions of interest (ROI) are defined through object edge event activity, reducing noise. ROI features are extracted for use in-depth perception.

Event-based tracking of human hand demonstrated feasible, in real time and at a low computational cost. The proposed ROI-finding method reduces noise from intensity images, achieving up to 89% of data reduction in relation to the original, while preserving the features. The depth estimation error in relation to ground truth (measured with wearables), measured using dynamic time warping and using a single event camera, is from 15 to 30 millimetres, depending on the plane it is measured.

Tracking of human hands in 3 D space using a single event camera data and lightweight algorithms to define ROI features (hands tracking in space).

We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.

The purpose of this paper is to achieve reliable estimation of yaw angles by fusing data from low-cost inertial and magnetic sensing.

In this paper, yaw angle is estimated by fusing inertial and magnetic sensing from a digital compass and a gyroscope, respectively. A Kalman filter estimates the error produced by the gyroscope.

Drift effect produced by the gyroscope is significantly reduced and, at the same time, the system has the ability to react quickly to orientation changes. The system combines the best of each sensor, the stability of the magnetic sensor and the fast response of the inertial sensor.

The system does not present a stable behavior in the presence of large vibrations. Considerable calibration efforts are needed.

Today, most of human–robot interaction technologies need to have the ability to estimate orientation, especially yaw angle, from small-sized and low-cost sensors.

Existing methods for inertial and magnetic sensor fusion are combined to achieve reliable estimation of yaw angle. Experimental tests in a human–robot interaction scenario show the performance of the system.

The purpose of this paper is to present a CAD‐based human‐robot interface that allows non‐expert users to teach a robot in a manner similar to that used by human beings to teach each other.

Intuitive robot programming is achieved by using CAD drawings to generate robot programs off‐line. Sensory feedback allows minimization of the effects of uncertainty, providing information to adjust the robot paths during robot operation.

It was found that it is possible to generate a robot program from a common CAD drawing and run it without any major concerns about calibration or CAD model accuracy.

A limitation of the proposed system has to do with the fact that it was designed to be used for particular technological applications.

Since most manufacturing companies have CAD packages in their facilities today, CAD‐based robot programming may be a good option to program robots without the need for skilled robot programmers.

The paper proposes a new CAD‐based robot programming system. Robot programs are directly generated from a CAD drawing “running” on a commonly available 3D CAD package (Autodesk Inventor) and not from a commercial, computer aided robotics (CAR) software, making it a simple CAD integrated solution. This is a low‐cost and low‐setup time system where no advanced robot programming skills are required to operate it. In summary, robot programs are generated with a high‐level of abstraction from the robot language.

Most industrial robots are still programmed using the typical teaching process, through the use of the robot teach pendant. This is a tedious and time‐consuming task that requires some technical expertise, and hence new approaches to robot programming are required. The purpose of this paper is to present a robotic system that allows users to instruct and program a robot with a high‐level of abstraction from the robot language.

The paper presents in detail a robotic system that allows users, especially non‐expert programmers, to instruct and program a robot just showing it what it should do, in an intuitive way. This is done using the two most natural human interfaces (gestures and speech), a force control system and several code generation techniques. Special attention will be given to the recognition of gestures, where the data extracted from a motion sensor (three‐axis accelerometer) embedded in the Wii remote controller was used to capture human hand behaviours. Gestures (dynamic hand positions) as well as manual postures (static hand positions) are recognized using a statistical approach and artificial neural networks.

It is shown that the robotic system presented is suitable to enable users without programming expertise to rapidly create robot programs. The experimental tests showed that the developed system can be customized for different users and robotic platforms.

The proposed system is tested on two different robotic platforms. Since the options adopted are mainly based on standards, it can be implemented with other robot controllers without significant changes. Future work will focus on improving the recognition rate of gestures and continuous gesture recognition.

The key contribution of this paper is that it offers a practical method to program robots by means of gestures and speech, improving work efficiency and saving time.

This paper presents an alternative to the typical robot teaching process, extending the concept of human‐robot interaction and co‐worker scenario. Since most companies do not have engineering resources to make changes or add new functionalities to their robotic manufacturing systems, this system constitutes a major advantage for small‐ to medium‐sized enterprises.

The magnetometer measurement update plays a key role in correcting yaw estimation in fusion algorithms, and hence, the yaw estimation is vulnerable to magnetic disturbances. The purpose of this study is to improve the ability of the fusion algorithm to deal with magnetic disturbances.

In this paper, an adaptive measurement equation based on vehicle status is derived, which can constrain the yaw estimation from drifting when vehicle is running straight. Using this new measurement, a Kalman filter-based fusion algorithm is constructed, and its performance is evaluated experimentally.

The experiments results demonstrate that the new measurement update works as an effective supplement to the magnetometer measurement update in the present of magnetic disturbances, and the proposed fusion algorithm has better yaw estimation accuracy than the conventional algorithm.

The paper proposes a new adaptive measurement equation for yaw estimation based on vehicle status. And, using this measurement, the fusion algorithm can not only reduce the weight of disturbed sensor measurement but also utilize the character of vehicle running to deal with magnetic disturbances. This strategy can also be used in other orientation estimation fields.

The aim of this paper is to revisit the Brazilian case in an effort to shed light on how state-business relations have been transformed in the contemporary era of globalization. Brazil has long been considered the archetype of “dependent development”, having served as the inspiration for the classic theory of the relationship between states and capital in the semi-peripheral states of the developing world. Since the theory of dependent development was initially formulated in the 1970s, however, both the Brazilian political economy and the global context in which it is situated have changed dramatically.

The analysis draws on 15 months of field research conducted in Sao Paulo, Brasilia, Beijing, New Delhi and Washington, as well as at the World Trade Organization (WTO) in Geneva, involving 157 interviews with senior government officials, trade negotiators and representatives of industry and non-governmental organizations, ethnographic observation and extensive documentary research.

The author shows how the emergence of a highly competitive export-oriented agribusiness sector in Brazil has prompted the expansion and internationalization of domestic capital, leading to the emergence of an independent, private sector lobby with considerable influence on the Brazilian state. Driven by the rise of Brazilian agribusiness, the state and capital have allied together to aggressively pursue the expansion of markets for Brazilian exports, specifically through dispute settlement and negotiations at the WTO.

These findings challenge conventional understandings of state-business relations in emerging economies such as Brazil.

For Lusophones, saudade is a common psychological experience related with the physical separation from loved ones and/or familiar locations. This study aims to examine the relationships between perception of discrimination, adaptation and saudade.

The sample consisted of 655 African migrants from Angola, Cape Verde, Guinea-Bissau and Mozambique living in Portugal with a mean age of 38 years. The average duration of stay in Portugal was 22 years.

Results indicated that length of residence impacted the difficulties experienced with saudade: respondents with longer lengths of stay in the society of settlement experienced less difficulty with saudade. As predicted, the results indicated that higher perceptions of discrimination and loneliness correlated positively with experienced saudade, while sociocultural adaptation correlated negatively with experienced saudade.

Path analysis was conducted to investigate mediation impacts of sociocultural adjustment and loneliness on the relationship between perception of discriminatory events and difficulty with saudade. This study suggests that sociocultural adaptation and loneliness partially mediated the relation between perception of discrimination and saudade. Notwithstanding the low level of perceived discrimination found in this African background sample, this antecedent plays a relevant role in the saudade experienced. This evidence may be useful in targeting programs to improve sociocultural adjustment and to reduce loneliness which may help to alleviate the difficulty with feeling saudade among African migrants.

The purpose of this paper is to discuss the role of contemporary architecture in heritage protection, reinterpretation and reuse, an issue that has become increasingly relevant due to the recognition of architectural heritage as a key factor for cultural and economic development.

In Portugal, as elsewhere in Europe, cultural heritage management has often been associated with the creation of new museum spaces, namely, within national monuments and archaeological sites. Drawing on restoration theories and international charters, this paper analyses and compares two parallel interventions recently built inside São Jorge Castle, in Lisbon: the Museum Centre (Victor Mestre and Sofia Aleixo, 2007-2008) and the Archaeological Site (João Luís Carrilho da Graça, 2008-2010). This approach offers insight on the complexity of addressing and reconfiguring the profusion of past transformations within a single monument.

These two complementary museum spaces are representative of different attitudes towards heritage appropriation, substantiating the thesis that musealizing always entails the creation of narratives, which translate history and heritage into architectural and curatorial discourses. Besides meeting the functional requirements of specific museum programmes, such interventions frequently deal with the challenge of opening up new perspectives on the past.

Considering the central role of communication in contemporary museums, this paper discusses how heritage musealization can contribute to the translation of historical evidence into updated iconographies, narratives and dialogues. Furthermore, the unique characteristics of this twofold case study can provide an insightful contribution for a broader debate on the reinterpretation of iconic monuments and sites.

The purpose of this paper is to present the application of the boundary element method (BEM) in linear elastic fracture mechanics for analysis of fatigue crack propagation problems in mixed-mode (I+II) using a robust academic software named BemCracker2D and its graphical interface BemLab2D.

The methodology consists in calculating elastic stress by conventional BEM and to carry out an incremental analysis of the crack extension employing the dual BEM (DBEM). For each increment of the analysis, the stress intensity factors (SIFs) are computed by the J-Integral technique, the crack growth direction is evaluated by the maximum circumferential stress criterion and the crack growth rate is computed by a modified Paris equation, which takes into account an equivalent SIF to obtain the fracture Modes I and II. The numerical results are compared with the experimental and/or BEM values extracted from the open literature, aiming to demonstrate the accuracy and efficiency of the adopted methodology, as well as to validate the robustness of the programs.

The paper addresses the numerical simulation of fatigue crack growth. The main contribution of the paper is the introduction of a software for simulating two-dimensional fatigue crack growth problems in mixed-mode (I+II) via the DBEM. The software BemCracker2D coupled to the BemLab2D graphical user interface (GUI), for pre/post-processing, are very complete, efficient and versatile and its does make relevant contributions in the field of fracture mechanics.

The main contribution of the manuscript is the development of a GUI for pre/post-processing of 2D fracture mechanics problems, as well as the object oriented programming implementation. Finally, the main merit is of educational nature.