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Delivery mode planning for distribution to brick-and-mortar retail stores: discussion and literature review
No full textIn the retail industry, there are multiple products flowing from different distribution centers to brick-and-mortar stores with distinct characteristics. This industry has been suffering radical changes along the years and new market dynamics are making distribution more and more challenging. Consequently, there is a pressure to reduce shipment sizes and increase the delivery frequency. In such a context, defining the most efficient way to supply each store is a critical task. However, the supply chain planning decision that tackles this type of problem, delivery mode planning, is not well defined in the literature. This paper proposes a definition for delivery mode planning and analyzes multiple ways retailers can efficiently supply their brick-and-mortar stores from their distribution centers. The literature addressing this planning problem is reviewed and the main interdependencies with other supply chain planning decisions are discussed. © 2017 Springer Science+Business Media New Yor
Hierarchical Hybrid Logic
Get PDFWe introduce HHL, a hierarchical variant of hybrid logic. We study first order correspondence results and prove a Hennessy-Milner like theorem relating (hierarchical) bisimulation and modal equivalence for HHL. Combining hierarchical transition structures with the ability to refer to specific states at different levels, this logic seems suitable to express and verify properties of hierarchical transition systems, a pervasive semantic structure in Computer Science
Using multi-relational data mining to discriminate blended therapy efficiency on patients based on log data
Get PDFBridging Automation and Robotics: an Interprocess Communication between IEC 61131–3 and ROS
Get PDFThe contemporary adoption of Cyber-Physical Systems and improvements in robotic applications in industrial scenarios demands for horizontal integration mechanisms with already existing automation equipment, controlled by PLCs. This paper aims to shorten the gap between the automation and robotics domain, by proposing an Interprocess Communication method to establish interoperability between robotic systems and automation equipment in a reliable and straightforward manner. In particular, this paper introduces a novel approach for linking ROS and IEC 61131-3 by way of shared memory interfaces, enabling and promoting their interactions. Moreover, this paper addresses the applied synchronization mechanism for handling concurrent accesses to the shared memory location, explores data type mapping between ROS and IEC 61131-3, and identifies some practical industrial applications.The research leading to these results has received funding
from the European Union’s Horizon 2020 - The EU Framework
Programme for Research and Innovation 2014-2020,
under grant agreement No. 723658.
This work is financed by the ERDF European Regional
Development Fund through the Operational Programme for
Competitiveness and Internationalisation - COMPETE 2020
Programme, and by National Funds through the Portuguese
funding agency, FCT - Fundac¸ ˜ao para a Ciˆencia e Tecnologia,
within project SAICTPAC/0034/2015- POCI-01-0145-
FEDER-01641
Stability of autonomous power systems with reversible hydro power plants: A study case for large scale renewables integration
No full textThis paper addresses the dynamic stability analysis of an islanded power system regarding the installation of a reversible hydro power plant for increasing renewable energy integration. Being a high-head facility, the hydro power plant consists of separated pumps and turbines (Pelton type). In order to properly support the identification of hydro pumps connection requirements and the technology to be used, different options were taken into consideration, namely: fixed speed pumps coupled to induction machines directly connected to the grid and adjustable speed pumps supplied by a drive system. Extensive numerical simulations of the power system's dynamic behaviour response allowed the evaluation of the hydro power plant's role for the purpose of grid stability conditions. These simulations showed that the high-head hydro power installation provides a marginal contribution to system frequency regulation when explored in turbine operation mode, leading to a reversible power station with a single penstock. Moreover, due to the significant additional system load introduced by the hydro pumping units, the obtained results clearly indicate that supplementary regulation flexibility is required to attend the need of assuring the stable operation of the system in case of critical disturbances such as grid faults. The study case demonstrates that, although the foreseen operation of a reversible hydro power plant creates new security challenges to overcome in an autonomous power system, robust technical solutions can be identified without increasing, from the local system operator's perspective, the operation complexity of the power system. © 2018 Elsevier B.V
Retinal image quality assessment by mean-subtracted contrast-normalized coefficients
No full textThe automatic assessment of visual quality on images of the eye fundus is an important task in retinal image analysis. A novel quality assessment technique is proposed in this paper. We propose to compute Mean-Subtracted Contrast-Normalized (MSCN) coefficients on local spatial neighborhoods of a given image and analyze their distribution. It is known that for natural images, such distribution behaves normally, while distortions of different kinds perturb this regularity. The combination of MSCN coefficients with a simple measure of local contrast allows us to design a simple but effective retinal image quality assessment algorithm that successfully discriminates between good and low-quality images, while delivering a meaningful quality score. The proposed technique is validated on a recent database of quality-labeled retinal images, obtaining results aligned with state-of-the-art approaches at a low computational cost. © 2018, Springer International Publishing AG
Evolution, Current Challenges, and Future Possibilities in ECG Biometrics
Get PDFFace and fingerprint are, currently, the most thoroughly explored biometric traits, promising reliable recognition in diverse applications. Commercial products using these traits for biometric identification or authentication are increasingly widespread, from smartphones to border control. However, increasingly smart techniques to counterfeit such traits raise the need for traits that are less vulnerable to stealthy trait measurement or spoofing attacks. This has sparked interest on the electrocardiogram (ECG), most commonly associated with medical diagnosis, whose hidden nature and inherent liveness information make it highly resistant to attacks. In the last years, the topic of ECG-based biometrics has quickly evolved toward the commercial applications, mainly by addressing the reduced acceptability and comfort by proposing new off-the-person, wearable, and seamless acquisition settings. Furthermore, researchers have recently started to address the issues of spoofing prevention and data security in ECG biometrics, as well as the potential of deep learning methodologies to enhance the recognition accuracy and robustness. In this paper, we conduct a deep review and discussion of 93 state-of-the-art publications on their proposed methods, signal datasets, and publicly available ECG collections. The extracted knowledge is used to present the fundamentals and the evolution of ECG biometrics, describe the current state of the art, and draw conclusions on prior art approaches and current challenges. With this paper, we aim to delve into the current opportunities as well as inspire and guide future research in ECG biometrics
