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This work demonstrates the development of a robot, which was designed for the orbital welding of pipes.

The robot consists of a small car pressed against the pipe by means of chains, which are used by the robot to move around it. To provide all necessary torch movements, the robot must have four degrees of freedom: torch travel speed, stick‐out, torch angle and lateral motion. Thus, using a look‐up table‐which was specially designed to this application‐it is possible to follow the optimal parameters (voltage, current, welding speed, torch angle and stick‐out) for each welding position (flat, vertical and overhead).

The robotization of the orbital welding process brings enhancement in the final product quality, considerable increase of repeatability, reduction of rework and reduction of the weld execution time. At the very least, the robot is capable to reproduce the weld bead of the best human welder, through the use of the same paramenters contained in a table.

The use of this robot in welding with GMAW proved to be extremely viable. It was shown that the bead shape did not suffer great variations from one welding postion to another, thanks to the use of a gradual change of parameters.

Although, by RIA definition the devices for the orbital welding shown in literature up to now are not robots, the developed device can be called a robot due to its capability of being completely programmable and automatically carrying through all welding activities.

This study aims to evaluate the presence of abnormal returns due to stock splits or reverse stock splits in the Brazilian capital market context.

The event study technique was used on data from 518 events that occurred in a 30-year period (1987–2016), comprising 167 stock splits and 351 reverse stock splits.

The results revealed the occurrence of abnormal returns around the time the shares began trading stock splits or reverse stock splits at a statistical significance level of 5%. The main conclusion is that stock split and reverse stock split operations represent opportunities for extraordinary gains and may serve as a reference for investment strategies in the Brazilian stock market.

This study innovates by including reverse stock splits, as the existing literature focuses on stock splits, and by testing two distinct “zero” dates that of the ordinary general meeting that approved the share alteration and the “ex” date of the alteration, when the shares were effectively traded, reverse split or split.

Many neo-Weberians adopt the state’s authority-monopolizing aim as their theoretical expectation. Through a case study of the Peruvian state and Lima’s squatter settlements, I provide evidence in support of the opposite contention: that states may unintentionally produce non-state extractive-coercive organizations. During the mid- to late-twentieth century, Lima’s population grew rapidly. Since they had few economic resources, the new urban poor requisitioned public lands and set up dozens of squatter settlements in the city’s periphery. Other researchers have identified several novel political phenomena stemming from such urban conditions. I focus here on the impact of the state. Using secondary and primary data, I examine three periods during which the state applied distinct settlement policies and one in which it did not apply a settlement policy, from 1948 to 1980. I find that when it applied each of the settlement policies, the state produced non-state political authorities – neighborhood elites – who extracted resources from squatters and tried to control neighborhood turf even against state encroachment, and that the state’s non-involvement did not produce them.

PREVI, Spanish initials for “experimental housing project”, was conceived in Lima in 1967. Among other initiatives, it launched an international architectural competition that led to the construction of a 500-unit compound based on proposals put forward by teams such as Atelier 5, Aldo van Eyck, and Íñiguez de Ozoño and Vázquez de Castro. The forty years that have lapsed in the interim and the ongoing transformation of the homes by their dwellers afford an opportunity to reflect on the suitability of the construction technologies proposed in the competition.

Ongoing growth and the rationalisation of construction methods were two of the basic premises underlying the competition. The remodelling that has taken place in the interim stands as proof of the success of the first premise, but the use of traditional techniques to build the additions calls some of the most sophisticated proposals for industrialisation into question.

At the time, the tendency was to rely on large-scale industrialisation, as can be seen in the German and Polish architects' proposals. Nonetheless, many of the PREVI proposals opted for rationalising construction and precasting short series of small elements, rather than huge three-dimensional members. In the situation presently prevailing in Latin America, the viability of some of the technological proposals deployed in the PREVI might be profitably revisited.

As the deployment of ICT and the Internet especially increases all around the world, the urgency of providing access to the “have-nots” appears at least diminished, with new issues and urgencies at the forefront. However, studies show that even when the best conditions for access are established, not everyone uses their digital devices for the same purposes, even when sharing the same goals, or when participating in the same experiences.

To explore potential explanations of these phenomena, this study examines survey data from students from a private university in Peru regarding their backgrounds and expertise with ICT. We use the twin concepts of social and cultural capital to establish a connection between their larger lifeworld experiences and their use of digital media. For this purpose, we analyze the data using polychoric correlations to explore patterns resulting from self-perception of access and skills, as well as processes related to social capital such as differentiated media use.

Findings indicate that there are differentiated processes of capital accrual using ICTs, but, at the same time, the productive and leisure dimensions of ICT use must be considered.

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 main objective of this study was to establish a model of competitiveness factors to measure the value of construction companies adequately.

A theoretical model of four main factors was developed, and they include human capital, ethical values, process innovation and financing. Information was collected from 18 construction companies in the city of Metropolitan Lima, collecting information on each of these factors. Through an analysis of the principal components, the weighting of each factor about the competitiveness of a construction company was determined.

The cost of person-hours, the cost of equipment to execute work, and the cost of materials used are the strongest indicators to measure the competitiveness of a construction company. On the other hand, the number of employees holding university degrees and the number of master builders holding technical degrees in the human capital factor also have a moderate weight in determining the competitiveness value of a company. The indicator of work delivered within the deadline also moderately affects competitiveness. Finally, the monthly debt payment indicator has a very small effect on the company’s competitiveness.

In conclusion, this study provides evidence of a competitiveness model with highly related factors on human capital, process innovation and ethical values as the most important in measuring competitiveness.

El objetivo principal de la investigación fue establecer un modelo de factores de competitividad para medir adecuadamente el valor de las empresas constructoras.

Se desarrolló un modelo teórico de cuatro factores principales, que incluyen el capital humano, los valores éticos, la innovación de procesos y el financiamiento. Se recolectó información de 18 empresas constructoras de la ciudad de Lima Metropolitana, recolectando información de cada uno de estos factores. A través de un análisis de componentes principales se determinó la ponderación de cada uno de ellos sobre la competitividad de una empresa constructora.

El costo de horas hombre, el costo de los equipos para ejecutar obras y el costo de material utilizado son los indicadores más fuertes para medir la competitividad de una empresa constructora. Por otro lado, la cantidad de empleados con títulos universitarios y la cantidad de maestros de obra con título técnico del factor de capital humano también tienen un peso moderado en la determinación del valor de competitividad de una empresa. El indicador de obras entregadas dentro de plazo también tiene un efecto moderado sobre la competitividad. Finalmente, el indicador de pago mensual de la deuda tiene un efecto muy pequeño sobre la competitividad de la empresa.

En conclusión, el estudio proporciona evidencia de un modelo de competitividad con factores altamente relacionados sobre el capital humano, la innovación de procesos y los valores éticos como los más importantes a la hora de medir la competitividad.

The purpose of this paper is to evaluate the predictive capacity of market risk estimation models in times of financial crises.

For this, value-at-risk (VaR) valuation models applied to the daily returns of portfolios composed of stock indexes of developed and emerging countries were tested. The Historical Simulation VaR model, multivariate ARCH models (BEKK, VECH and constant conditional correlation), artificial neural networks and copula functions were tested. The data sample refers to the periods of two international financial crises, the Asian Crisis of 1997, and the US Sub Prime Crisis of 2008.

The results pointed out that the multivariate ARCH models (VECH and BEKK) and Copula-Clayton had similar performance, with good adjustments in 100 percent of the tests. It was not possible to perceive significant differences between the adjustments for developed and emerging countries and of the crisis and normal periods, which was different to what was expected.

Previous studies focus on the estimation of VaR by a group of models. One of the contributions of this paper is to use several forms of estimation.

Several studies have aimed to develop robotic systems which move in transmission lines. Until this moment, all of them have a high weight and cost associated with the equipment and reduced battery autonomy time. In this context, this paper aims to propose the POLIBOT (POwer Lines Inspection roBOT) with low cost and weight, enabling the movement over the lines and an easier installation and remove.

The designed robot uses the Profiles Manufacturing Methodology (PMM). The construction of the robot mechanical structure uses modularized aluminum parts built through square profiles. Thus, it’s possible a drastic reduction in production time as well as cost reduction and weight when comparing this method with other manufacturing processes like foundry, for example. For hardware and software systems, the use of free and open source software causes a significant reduction in cost and project execution time. The benefits of using open source systems are immeasurable, both from academic and industrial applications.

The POLIBOT platform is one solution to the problem of inspection in power lines. With this robot, more lines are maintained with lower time. In its constructive aspect, the robotic mechanism is designed using principles of bioengineering. The use of this principle was successful, considering that obstacle transposition is performed with stability and low energy consumption.

The suggestion for future researches is to replace the battery for solar energy and construction in polymeric material to avoid high magnetic fields.

The commercial application is evident because manual inspections are inefficient, very expensive and dangerous. Thus, it is growing the number of researches that develop mechatronics systems for this kind of inspection.

The impact is the reduction of accidents because the present procedure requires precision of movements, where the pilot and electrical technician are close to high electrical and magnetic fields. In addition, for some tasks, the worker has to walk on the line to reach some important points. Thus, those tasks involve high risk of death.

The PMM methodology represents an innovation to the state of the art because others robotic mechanisms proposed for inspection tasks present total structure mass between 50 and 100 kg and POLIBOT has only 9 kg. Other fact is its price for implementation as this robot used the robot operating system (ROS) framework, what dispense the use of licenses. Other important features are that the robot performs the tasks autonomously, which reduces errors introduced by the operator and its low manufacturing cost as compared with other projects.

The objective of this work is to investigate the existence of structural breaks in multicointegration models estimated for Brazilian fiscal variables and to identify their effects on the sustainability or not of this country`s fiscal policy between December 1997 and June 2018.

The authors apply the econometric multicointegration method, in order to analyze long-term relationships between accumulated revenue and expenses of Brazilian central government and the stock of its debt, incorporating structural breaks, over the study period.

The unsustainability of the debt/GDP ratio is found here, as in a previous work, but now considering a structural break. As one of the contributions, the present work makes it possible to identify the date as of which Brazilian fiscal policy may have become unsustainable: May 2014.

The work points out the worsening of Brazilian fiscal situation as of 2014. The authors adapted original methodologies both in model specification and in the stationarity test used. The estimated parameters before and after structural break allow for identifying changes in fiscal variables that may have led to unsustainability, thus providing possible guidance for fiscal policy.