Abstract
This survey presents a literature review on the machine and control systems applied in friction stir welding (FSW) with a special focus on the new trends, i.e., using robots and force control. The physical process of FSW is described and the main parameters that are relevant to select a machine and establish a control system are highlighted. The paper reviews in detail the role of the following parameters of a given machine for FSW: force, stiffness, accuracy, sensing, decision-making and flexibility capabilities. They will be compared in terms of the different machines, namely the conventional machine tools, dedicated FSW machines, parallel kinematic robots, and articulated robots. It is stated that articulated arm robots have enormous potentialities in the industrialization of the process, but they also have important limitations namely related to positional accuracy. A quality FSW weld produced by a robot depends on the fine tuning of some process parameters and force/motion control capabilities. Control systems can deal with these limitations. The different approaches to the control systems applied in FSW are presented and their advantages/drawbacks are discussed.

Abstract
Destination image is critical for the development of tourism, particularly for islands where the scarcity of resources requires special care in focusing on the few determinants the islands have. This paper aims to describe the most perceived image determinants by tourists of Cape Verde. Based on a convenience sample of 627 international tourists, a second order factor analysis model was validated through the model fit measures. Despite a scarcity of resources, the results suggest that the image of Cape Verde is a multidimensional construct comprising five factors: natural attractions, man-made attractions, amenities, culture and price. Among these, the man-made and natural attractions as well as amenities are the most important image determinants for Cape Verde. Potentially there is a plurality of dimensions to be appreciated in the positioning process. Challenging many studies which have almost exclusively emphasised the attractions of natural resources, the tourism sector of this destination can offer a major and more flexible competitive advantage. The results may be helpful to other African countries which share similar developmental constraints with Cape Verde. © 2017 Nova Science Publishers, Inc.

Abstract
The aim of this paper is to present the development of an innovative experimental reflective pulse oximetry solution targeting wearable health system for daily monitoring purposes. The measurement of two common human physiological indicators is performed, which are the pulse rate and the blood oxygenation level (SpO(2)). The design options are detailed, covering photoplethysmographic (PPG) signals sensing architecture and post- processing digital filter operations. The high resolution of the physiological measures is achieved using sigma delta conversion technique. Conclusions are duly drawn.

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The scarcity of federal resources allocated to the Ministry of Defense causes the need for Brazilian Armed Forces to implement strategies that may allow achieving "more with less". For the Navy of Brazil, this strategy includes the need to improve and implement risk management tools and techniques in large defense projects. In this sense, the present study aims at contributing to this process through the design and validation of a synthetic risk model for military shipbuilding, containing the main risk events, causes and associated effects that may affect the success of these projects, in terms of costs and deadlines. This model will help in the prediction and control of these variables and their possible effects, enabling the anticipation of responses and the reduction of uncertainty. (C) 2016 The Authors. Published by Elsevier B.V.