Abstract
Data-driven decision support systems rely on increasing amounts of information that needs to be converted into actionable knowledge in business intelligence processes. The latter have been applied to diverse business areas, including governmental organizations, where they can be used effectively. The Portuguese Food and Economic Safety Authority (ASAE) is one example of such organizations. Over its years of operation, a rich dataset has been collected which can be used to improve their activity regarding prevention in the areas of food safety and economic enforcement. ASAE needs to inspect Economic Operators all over the country, and the efficient and effective generation of optimized and flexible inspection routes is a major concern. The focus of this paper is, thus, the generation of optimized inspection routes, which can then be flexibly adapted towards their operational accomplishment. Each Economic Operator is assigned an inspection utility - an indication of the risk it poses to public health and food safety, to business practices and intellectual property as well as to security and environment. Optimal inspection routes are then generated typically by seeking to maximize the utility gained from inspecting the chosen Economic Operators. The need of incorporating constraints such as Economic Operators' opening hours and multiple departure/arrival spots has led to model the problem as a Multi-Depot Periodic Vehicle Routing Problem with Time Windows. Exact and meta-heuristic methods were implemented to solve the problem and the Genetic Algorithm showed a high performance with realistic solutions to be used by ASAE inspectors. The hybrid approach that combined the Genetic Algorithm with the Hill Climbing also showed to be a good manner of enhancing the solution quality.

Abstract
This paper investigates the issue of robust frequency regulation of single-area alternating current (AC) power applications. The robust stability and disturbance rejection performance criteria are considered in the design procedure of an output feedback controller. Four cases of single-area AC power systems, which comprise the different types of governors and generators, are considered. These components are modeled by first- and second-order transfer functions and exhibit non(minimum) phase behavior. Based on the uncertain linear transfer functions of the governors and generators, the resilient controller against uncertainties and unknown power load demand is designed numerically. Several numerical simulations are carried out to show the merits of the developed controller. Also, the effects of different types of governors and generators on the AC MG frequency deviation are also investigated.

Abstract
The rising number of people living in city centers is connected to an increase of private vehicles, traffic, and associated harmful effects. Efforts have been made to promote a modal shift to the use of more sustainable transportation means, such as walking and cycling, but several factors hinged to safety, comfort, and accessibility, still hinder this goal. Current route planners often focus on two particular dimensions, time and distance, which might not be enough to support other personal perceptions. We need to consider new aspects and different dimensions, such as air quality, noise levels, or people density, fueled by the recent advances in the area of sensorization and the Internet of Things. We tested the idea of an innovative route planner with surveys and focus groups and concluded that there is an interest for more power to customize personal routes, which could be a key element boosting soft mode mobility. © 2021, AHFE International. All rights reserved.

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Abstract
The spin of the supermassive black hole that resides at the Galactic Center can, in principle, be measured by accurate measurements of the orbits of stars that are much closer to Sgr A* than S2, the orbit of which recently provided the measurement of the gravitational redshift and the Schwarzschild precession. The GRAVITY near-infrared interferometric instrument combining the four 8m telescopes of the VLT provides a spatial resolution of 2-4 mas, breaking the confusion barrier for adaptive-optics-assisted imaging with a single 8-10m telescope. We used GRAVITY to observe Sgr A* over a period of six months in 2019 and employed interferometric reconstruction methods developed in radio astronomy to search for faint objects near Sgr A*. This revealed a slowly moving star of magnitude 18.9 in the K-band within 30 mas of Sgr A*. The position and proper motion of the star are consistent with the previously known star S62, which is at a substantially greater physical distance, but in projection passes close to Sgr A*. Observations in August and September 2019 detected S29 easily, with K-magnitude of 16.6, at approximately 130 mas from Sgr A*. The planned upgrades of GRAVITY, and further improvements in the calibration, offer greater chances of finding stars fainter than K-magnitude of 19.

Abstract