38 research outputs found

    Storage and Ingestion Systems in Support of Stream Processing: A Survey

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    Under the pressure of massive, exponentially increasing amounts ofheterogeneous data that are generated faster and faster, Big Data analyticsapplications have seen a shift from batch processing to stream processing,which can reduce the time needed to obtain meaningful insight dramatically.Stream processing is particularly well suited to address the challenges of fog/edgecomputing: much of this massive data comes from Internet of Things (IoT)devices and needs to be continuously funneled through an edge infrastructuretowards centralized clouds. Thus, it is only natural to process data on theirway as much as possible rather than wait for streams to accumulate on thecloud. Unfortunately, state-of-the-art stream processing systems are not wellsuited for this role: the data are accumulated (ingested), processed andpersisted (stored) separately, often using different services hosted ondifferent physical machines/clusters. Furthermore, there is only limited support foradvanced data manipulations, which often forces application developers tointroduce custom solutions and workarounds. In this survey article, wecharacterize the main state-of-the-art stream storage and ingestion systems.We identify the key aspects and discuss limitations and missing features inthe context of stream processing for fog/edge and cloud computing. The goal is tohelp practitioners understand and prepare for potential bottlenecks when usingsuch state-of-the-art systems. In particular, we discuss both functional(partitioning, metadata, search support, message routing, backpressuresupport) and non-functional aspects (high availability, durability,scalability, latency vs. throughput). As a conclusion of our study, weadvocate for a unified stream storage and ingestion system to speed-up datamanagement and reduce I/O redundancy (both in terms of storage space andnetwork utilization)

    New Training Trends in High-Risk Technology Fields

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    The more developed new and sophisticated technologies are, as in the energy sector, paradoxically, the more critical people are in terms of competences. A prophecy for 2020 was that machines and robots would replace people. It happened mainly for routine activities. Therefore, humans remain a crucial element in the technology world, especially in high-risk areas, such as nuclear. Companies developing, using high-risk technologies employ people with high-technical knowledge - not enough. Poor communication, failing leadership, improper management, decision reluctance, generation gap, lacking teamwork competencies were human errors that caused accidents. Besides technical competences, these people also need consistent training and workshops on soft skills, leadership, and strategy. Besides generic skills, requirements for training staff in long-life cycle technologies should consider: specific reaction patterns for various generations; the high-risk technologies are a combination of technologies with various durations, e.g., Silicon-based digital technology life cycle is about five years. However, the digital technology evolution to new ones, like quantum computing, may trigger unexpected interfaces with the underlying reactor technology, dominant in a nuclear plant, and requirements for training of staff. Extended use of the well-trained competencies can make the difference between life and death; Training? Because it is a combination of knowledge and practice; Coaching? Because it generates new behaviors in ordinary situations and improves the work-unit relationship; Leadership? Because there are moments when people need someone leading them to accomplish tasks efficiently. The methodology used to investigate such aspects was of team-group interviews for diverse generations involved in a nuclear project for risk analyses and master students, by using the same combination of training and coaching exercises. The paper presents the results of these investigations, considering the aspects mentioned and contributes to raising awareness of strategic development approaches for employees to aim at the emergence of new leaders

    Design and Construction of a New Plasma Applicator for the Improved Disinfection and Activation of Large Surfaces

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    This paper describes the design and operation of a low-cost plasma applicator based on a patented, swirled-type dielectric barrier discharge configuration with a treatment width up to 300 mm. Differences from earlier plasma applicators include: blown cylindrical dielectric barrier discharge, combining the functional properties of the plasma jet systems, arc and corona discharge blown in a single type of universal applicator, and the possibility of treating large areas of samples with cold plasma generated in a certain type of specific process gas mixture chosen according to the type of desired effect. We tested the effect of the plasma on a few materials such as cotton and linen fabrics, glass wafers and printing cardboard, proving that the generated plasma can easily make hydrophilic or hydrophobic surfaces. We also tried the plasma’s sterilizing effect on Escherichia coli (E. coli) bacteria. The results suggest that our plasma system can be successfully applied to medical and biological fields as well, where the removal of bacteria and their fragments is required

    A NEW ROMAN REPUBLICAN HOARD IN PRE-ROMAN DACIA (ROMANIA). A PRELIMINARY NOTE. THE MINTING PLACE OF A HYBRID TYPE

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    The discovery of a new hoard consisting of Roman republican denarii has led to the re-opening of an old debate on the copying/imitation phenomenon of Republican denarii in pre-Roman Dacia. A case study is presented in this study on one piece from this hoard. At first sight, the coin looks as a genuine denarius, but at a closer look reveals not only that the piece is a hybrid but also that between the two prototypes of obverse and reverse was a period of 25 years. Despite the widespread phenomenon of copying Roman republican denarii in pre-Roman Dacia, the metal analyses of this coin revealed the absence of the lead (Pb) from its composition. A metal that is always present in the other cases of copies or imitations of Roman republican denarii found in Dacia

    Morphological and Micromorphological Description of the Larvae of Two Endemic Species of Duvalius (Coleoptera, Carabidae, Trechini)

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    The morphological and ultrastructural descriptions of the larvae of two cave species of Trechini—Duvalius (Hungarotrechus) subterraneus (L. Miller, 1868) and Duvalius (Biharotrechus) paroecus (J. Frivaldszkyi, 1865)—are presented in this paper. The interest in studying these larvae lays in their rarity and the limited distribution of the Duvalius species. The larvae were collected from caves in the Romanian Carpathians and were examined under a stereomicroscope and scanning electron microscopy. New important taxonomical and fine morphological characteristics are discussed together with conclusions on the larvae microhabitat as part of the measures to be taken by a proper management of caves

    Analysis of Functionalized Ferromagnetic Memory Alloys from the Perspective of Developing a Medical Vascular Implant

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    Durable biocompatible metal vascular implants are still one of the significant challenges of contemporary medicine. This work presents the preparation of ferromagnetic biomaterials with shape memory in metal strips based on FePd (30 at% Pd) that is either not doped or doped with Ga and Mn, coated with poly(benzofuran-co-arylacetic acid) or polyglutamic acid. The coating of the metal strips with polymers was achieved after the metal surface had been previously treated with open-air cold plasma. The final functionalization was performed to induce anti-thrombogenic/thrombolytic properties in the resulting materials. SEM-EDX microscopy and X-ray photoelectron microscopy (XPS) determined the morphology and composition of the metal strips covered with polymers. In vitro tests of standardized thromboplastin time (PTT) and prothrombin time (PT) were performed to evaluate the thrombogenicity of these biofunctionalized materials for future possible monitoring of the implant in patients

    Modification of Cotton and Leather Surfaces Using Cold Atmospheric Pressure Plasma and TiO<sub>2</sub>-SiO<sub>2</sub>-Reduced Graphene Oxide Nanopowders

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    Surface modification of textile fabrics and leathers is very versatile and allows the products quality improvement. In this work, cotton and leather substrates were pre-treated with cold atmospheric pressure plasma (CAPP) and further coated with TiO2-SiO2-reduced graphene oxide composites in dispersion form. By using a Taguchi scheme, this research evaluated the effect of three significant parameters, i.e., the pre-treatment with CAPP, organic dispersion coating and TiO2-SiO2-reduced graphene oxide (TS/GR) composites, that may affect the morpho-structural properties and photocatalytic activity of modified cotton and leather surfaces. The characteristics of cotton/leather surfaces were evaluated by morphological, structural, optical and self-cleaning ability using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX), X-ray powder diffraction (XRD), attenuated total reflection–Fourier Transform Infrared spectroscopy (ATR-FTIR) and UV–Vis spectroscopy. The self-cleaning performance of the obtained cotton and leather samples was evaluated by photocatalytic discoloration of berry juice surface stains under UV light irradiation for 12 h. The successfulness of coating formulations was proven by the SEM analysis and UV–Vis spectroscopy. The XRD patterns and ATR-FTIR spectra revealed the cellulose and collagen structures as dominant components of cotton and leather substrates. The CAPP treatment did not damage the cotton and leather structures. The photocatalytic results highlighted the potential of TiO2-SiO2-reduced graphene oxide composites in organic dispersion media, as coating formulations, for further use in the fabrication of innovative self-cleaning photocatalytic cotton and leather products

    Single-Pass VDD Pacing Lead for Cardiac Resynchronization Therapy: A Reliable Alternative

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    (1) Background: Cardiac resynchronization therapy (CRT) systems can be simplified by excluding the atrial lead and using a Ventricular-Dual-Dual (VDD) pacing lead. Possible disadvantages might include atrial undersensing and Ventricular-Ventricular-Inhibition (VVI) pacing. Because literature data concerning these systems are scarce, we analyzed their benefits and technical safety. (2) Methods: this retrospective study compared 50 patients implanted with VDD–CRT systems (group A), mainly because of unfavorable venous anatomy concerning the complication rate, with 103 subjects with Dual-Dual-Dual (DDD)–CRT systems (group B) implanted during 2000–2016 and 49 (group C) during 2016–2020. To analyze the functional parameters of the devices, we selected subgroups of 27 patients (subgroup A) and 47 (subgroup B) patients with VDD–CRT in 2000–2016, and 36 subjects (subgroup C) with DDD–CRT implanted were selected in 2017–2020. (3) Results: There was a trend of a lower complication rate with VDD–CRT systems, especially concerning infections during 2000–2016 (p = 0.0048), but similar results were obtained after rigorous selection of patients and employment of an upgraded design of devices/leads. With a proper device programing, CRT pacing had similar results, atrial undersensing being minimal (p = 0.65). For VDD-systems, VVI pacing was recorded only 1.7 ± 2.24% of the time. (4) Conclusions: In patients with a less favorable venous anatomy, VDD–CRT systems may represent a safe alternative regarding complications rates and functional parameters
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