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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.

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.

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.

The purpose of this paper is to conduct a general review of the ethnographic method. It uses metaphors to read several pieces of ethnographic research and discuss the different issues encountered during the research process. The review consisted of new articles but also important books that helped to construct and maintain the field of organizational ethnography.

The paper aims to discuss the ethnography research process through the metaphor of the Christian Seven Sins. It proposes a reflection on planning and conducting ethnographic research. The seven sins are used as a metaphor that can lead to more reflexive research for educational and explanatory purposes. Ultimately, the authors encourage organizational scholars to conduct ethnographic research.

The metaphors of the Christian seven sins represent issues that may arise during an ethnographic research. Gluttony is the dive in all topics that may appear; Greed is to lose yourself in the amount of data; Lust is to get too much involved in the field; Wrath is to take the struggles of the subjects as your own; Envy is to judge other's research according to your paradigm; Sloth is to not collect enough ethnographic data and Pride is forgetting to have a critical perspective toward your data. The redemption of these “sins” brings reflexivity to ethnographic research.

The paper opts to treat ethnography as a methodology that can be utilized with different epistemological and ontological approaches which could diminish the degree of reflection. No metaphor would be able to explain all the details of an ethnographic research project, still the seven sins provided a wide range of ideas to be reflected upon when using the methodology.

As a paper on ethnography, researchers and especially PhD students and early careers can get to know the issues that can arise during ethnographic research and put them in contact with good examples of ethnography in Organization and Management Studies.

This paper groups different complexities and discussions around ethnographic research that may entail research reflexivity. These ideas were scattered through various ethnographic publications. With the review their highlights can be read in a single piece. With these discussions, the paper aims to encourage researchers to conduct good quality ethnography.

This paper aims to present a new approach, called hybrid model reference adaptive controller or H-MRAC, for the hybrid controller (proportional-integral-derivative [PID + MRAC]) that will be used to control the position of a pneumatic manipulator.

It was developed a McKibben muscle using nautical mesh, latex and high-density polyethene connectors and it was constructed an elbow manipulator with two degrees of freedom, driven by these muscles. Then it was presented the H-MRAC control law based on the phenomenological characteristics of the plant, aiming at fast response and low damping. Lyapunov's theory was used as the project methodology, which ensures asymptotic stability for the control system.

It was developed a precise control system for a pneumatic manipulator and the results were compared to previous research.

In collaborative robotics, human and machine occupy the same workspace. This research promotes the development of safer and more complacent mechatronic systems in the event of collisions.

As a practical implication, the research allows the substitution of electric motors by McKibben muscles in industrial robots with high accuracy.

The pneumatic manipulator will make the human-robot physical interaction safer as it can prevent catastrophic collisions causing victims or equipment breakdown.

When compared to results in the literature, the present research showed a 37.51% and 36.74% lower global error in position tracking than MRAC and Adaptive proportional-integral-derivative (A-PID), respectively, validating its effectiveness.

The purpose of this paper is to understand the role of resilience enablers in combating counterfeits in the medicine supply chain based on a Systematic Literature Review (SLR). The objective is also to help practitioners and scholars as the review revealed that little research has been conducted on selecting and implementing practices to improve resilience to counterfeiting.

Based on the literature review, a content analysis was performed for 84 selected papers to explore the potential relationship among resilience enablers and counterfeit anti-measures.

This paper contributes to Supply Chain Resilience (SCR) research by summarizing the highly fragmented literature concerning how to combat counterfeiting. The SLR indicated reengineering, collaboration, visibility, innovation, SCR culture and trust as six key enablers to combat counterfeit medicines and identified literature gaps. Moreover, the paper discusses other resilience enablers which have been less studied in the literature and shows new avenues of research.

This paper is limited in that it is an exploratory literature review and focuses only on three databases over the past 15 years. Furthermore, counterfeit is a rapidly evolving issue and anti-measure studies require frequent surveillance concerning new discoveries.

The main contribution of this paper is to provide a better understanding of enablers most often associated with counterfeit anti-measures, which, therefore, might help to increase resilience to counterfeit medicines. Moreover, research gaps involving enablers less associated with anti-measures are presented.

The purpose of this paper is to develop and test a quality management system (QMS) implementation process for a medical devices manufacturer, which are covered by ISO 13485:2007 and RDC No. 59:2000 and based on operations strategy content definitions.

The research strategy is based on the Cambridge approach which is supported by action research techniques for producing “application” processes. This research strategy is also known as the “Process Approach” or “the Engineering Approach” and was developed in the mid-1990s by researchers from the “Institute for Manufacturing” (IFM/University of Cambridge).

The results reveal how real conditions “shape” implementation, indicating solutions for integrating procedures for performance and control indicators that represent manufacturing strategy objectives. The regulatory framework and the manufacturing environment offer these real conditions. The operations strategy that is underlying implementation shows how to reconcile regulation and strategy through its content.

The developed process can be improved by increasing the number of test cases until they bring no new contributions for its evolution. However, because it is a long-term and complex implementation process, the present research was concluded with a full understanding of process development.

The QMS implementation process based on the Cambridge Engineering approach creates several opportunities for discussing QMS design requirements, but also in testing procedures for quality policy deployment. Learning by doing is a practical contribution of the process as a participative component effectively applied in different moments at the mentioned workshops – WSH. The logical organization of the QMS implementation process shows causalities among manufacturing strategy, QMS and performance measurements, creating strategic coherence among the connected elements.

Although many studies had approached the QMS implementation, few of them actually addressed the system integration with the business strategic objectives. None of the studies to date related the implementation to the ISO 13485:2003 and the RDC No. 59.