Abstract
The safety of people and spaces is of paramount importance for societies. With time, the implementation of safety measures is rapidly changing from a need to a priority. Video surveillance systems play a key role in the surveillance of crucial and critical areas as these systems help the authorities keep places safer. With the rapid growth of technology and the implementation of the smart city concept, it is becoming possible to develop and deploy wide area surveillance systems. The ease with which these systems can be installed in private and public spaces (e.g., homes, streets and parks) allow for the creation of ubiquitous monitored environments. Rapid intervention responses to any abnormal situation or the use of recorded video as evidence are some advantages of the use of this type of surveillance systems. Although ubiquitous video surveillance systems are relevant for present modern societies, their cost is still high. To solve or, at least to mitigate this problem, a low-cost smart surveillance system was developed, which is presented and described in this paper. The developed surveillance system, based on available low-cost technology, can help keep critical spaces under surveillance 24/7. The proposed solution was found to have a minimal cost, a low bandwidth, and to be scalable and adaptable to every client’s needs. Thus, the solution can be used by anybody (private and public) and applied in different contexts (e.g., residential, industrial). The system can provide still images, captured from surveillance video cameras, real time video and real time video processing, which can be used for motion detection. When this happens, the user is warned via an e-mail containing the identification of the respective surveillance camera. Only the relevant video events are sent, recorded and maintained in the cloud platform system, consequently reducing the amount of storage space required to maintain all the historical video events. The results of the tests carried out show that it is possible to stream a video from the surveillance cameras with an insignificant delay and that motion detection can be attained through real time video processing. The system presented potentiates a low-cost solution for a smart city in the surveillance field. © Springer International Publishing AG, part of Springer Nature 2018.

Abstract
A flexible control of the distribution system is an efficient strategy to enhance the grid reliability and quality of service, in this sense, the maneuver devices play an important role to reach flexibility under network faults. In this direction, the present work proposes a new approach to solve the allocation problem of optimal maneuver devices in electric distribution systems (EDS) that considers both permanent and temporary faults. The considered maneuver devices are normally closed switches coupled to the beginning or to the end of distribution branches. The objective is to improve the system reliability with minimal investment cost. The metaheuristic and bio-inspired technique known as artificial immune system (AIS) is applied to handle the discrete feature of the switch allocation problem. The index considered to evaluate the reliability is the system expected outage cost to customers due to supply outages (ECOST). The paper includes a case study with four different simulations using the well-know RBTS Bus 4 test system The obtained results were compared to the literature ones and proved that the proposed approach can lead to promising solutions that establish a suitable trade-off between the reliability and the utility costs. © 2018 Power Systems Computation Conference.

Abstract
The constant search for methods that allow the production processes improvement is a driving force for the development and integration of current technological solutions in systems which are, currently, still purely human based. It is in this context that the company "Factoryplay" comes forward with the challenge to upgrade its current sewing stations by adding a set of mechanization and automation solutions. This article documents the steps carried out to provide the current solution with the required technical attributes. In this paper, the instrumentation and actuation devised solutions, as well as the method employed to design an embedded PI controller, will be presented. The PI controller allows the closed-loop control of the station movement speed as a function of the sewing machine speed. The practical results obtained, regarding the dynamic response of the sewing station, are in line with the simulated ones.

Abstract
The benefits of blockchain go beyond its applicability in finance. Electronic Voting Systems (EVS) are considered as a way to achieve a more effective act of voting. EVS are expected to be verifiable and tamper resistant. The blockchain partially fulfills this requirements of EVS by being an immutable, verifiable and distributed record of transactions. The adoption of EVS has been hampered mainly by cultural and political issues rather than technological ones. The authors believe that blockchain is the technology that, due to the overall attention it has been receiving, is capable of fostering the adoption of EVS. In the current work we compare blockchain-based EVS, identifying their strengths and shortcomings. © Springer Nature Switzerland AG 2019.

Abstract

Abstract
Measuring human gait is important in medicine to obtain outcome parameter for therapy, for instance in Parkinson's disease. Recently, small inertial sensors became available which allow for the registration of limb-position outside of the limited space of gait laboratories. The computation of gait parameters based on such recordings has been the subject of many scientific papers. We want to add to this knowledge by presenting a 4-segment leg model which is based on inverse kinematic and Kalman filtering of data from inertial sensors. To evaluate the model, data from four leg segments (shanks and thighs) were recorded synchronously with accelerometers and gyroscopes and a 3D motion capture system while subjects (n = 12) walked at three different velocities on a treadmill. Angular position of leg segments was computed from accelerometers and gyroscopes by Kalman filtering and compared to data from the motion capture system. The four-segment leg model takes the stance foot as a pivotal point and computes the position of the remaining segments as a kinematic chain (inverse kinematics). Second, we evaluated the contribution of pelvic movements to the model and evaluated a five segment model (shanks, thighs and pelvis) against ground-truth data from the motion capture system and the path of the treadmill. Results: We found the precision of the Kalman filtered angular position is in the range of 2-6 degrees (RMS error). The 4-segment leg model computed stride length and length of gait path with a constant undershoot of 3% for slow and 7% for fast gait. The integration of a 5th segment (pelvis) into the model increased its precision. The advantages of this model and ideas for further improvements are discussed.