Search results for "Machines"
showing 10 items of 113 documents
Human experts vs. machines in taxa recognition
2020
The step of expert taxa recognition currently slows down the response time of many bioassessments. Shifting to quicker and cheaper state-of-the-art machine learning approaches is still met with expert scepticism towards the ability and logic of machines. In our study, we investigate both the differences in accuracy and in the identification logic of taxonomic experts and machines. We propose a systematic approach utilizing deep Convolutional Neural Nets with the transfer learning paradigm and extensively evaluate it over a multi-pose taxonomic dataset with hierarchical labels specifically created for this comparison. We also study the prediction accuracy on different ranks of taxonomic hier…
On achieving intelligent traffic-aware consolidation of virtual machines in a data center using Learning Automata
2018
Unlike the computational mechanisms of the past many decades, that involved individual (extremely powerful) computers or clusters of machines, cloud computing (CC) is becoming increasingly pertinent and popular. Computing resources such as CPU and storage are becoming cheaper, and the servers themselves are becoming more powerful. This enables clouds to host more virtual machines (VMs). A natural consequence ofthis is that many modern-day data centers experience very high internaltraffic within the data centers themselves. This is, of course, due to the occurrence of servers that belong to the same tenant, communicating between themselves. The problem is accentuated when the VM deployment t…
Achieving Intelligent Traffic-aware Consolidation of Virtual Machines in a Data Center Using Learning Automata
2016
Cloud Computing (CC) is becoming increasingly pertinent and popular. A natural consequence of this is that many modern-day data centers experience very high internal traffic within the data centers themselves. The VMs with high mutual traffic often end up being far apart in the data center network, forcing them to communicate over unnecessarily long distances. The consequent traffic bottlenecks negatively affect both the performance of the application and the network in its entirety, posing nontrivial challenges for the administrators of these cloudbased data centers. The problem can, quite naturally, be compartmentalized into two phases which follow each other. First of all, the VMs are co…
High-Speed Machines: Typologies, Standards, and Operation under PWM Supply
2018
This paper presents an overview of the most recent state of the art in the field of high-speed electric machines fed through high-frequency converters. This type of systems is rapidly wide spreading in aeronautical and automotive applications, as well as microturbines. Each typology has its own advantages and downsides, which are analytically presented in this paper. Some types of high-speed electric machines require high-frequency voltage supply, highly stressing the dielectric materials of the winding insulation system. For this reason, in high-speed electric drives, premature failure may occur and a reduction of the total system reliability has been observed in the past years. Such issue…
Obsolescence and intervention: on synthetic-biological entities.
2014
Oftentimes, topics that might fall outside of science’s remit seem to end up becoming a part of it, sooner or later. This appears to be the case of synthetic biology, a new biological science (although some maintain that it is a form of engineering, or treat it as such; Endy, 2005), which seems to have become essential to the understanding of living beings and their extreme manipulation. I believe it to be a new form of biology. In truth, synthetic biology has a long history and, conceptually speaking, may well have formed part of the interests and research efforts of our illustrious predecessors throughout the first half of the twentieth century and even earlier. In any event, and broadly …
Le genre des bris de machines : violence et mécanisation à l’aube de l’ère industrielle (Angleterre-France, 1750-1850)
2013
Les bris de machines constituent un type de violence recurrent en Angleterre et en France au debut de l’ere industrielle. Ce type de violence contestataire a ete peint essentiellement sous les traits d’une pratique masculine, impliquant le triomphe d’une conception virile des rapports sociaux et des conflits du travail. Loin d’etre marginales ou invisibles, les femmes sont pourtant bien presentes dans ces conflits, a la fois comme auxiliaires des hommes mais aussi comme actrices de plein droit insurgees contre les machines qui portent atteinte a la production domestique et a leur mode de vie. En examinant le genre des bris de machines, il s’agit a la fois de suivre comment les machines requ…
A Simulation Analysis of VSM Control for RES plants in a Small Mediterranean Island
2020
The paper presents an application of Virtual Synchronous Machine control for managing inverter-interfaced renewable energy sources in a small Mediterranean island not supplied by the main grid. In the proposed analysis, the island's renewables-based generators area assumed interfaced to the grid by voltage source converters with a swing controller and a vector-current controller with two different options for the reference current for regulating the voltage at the Point of Common Coupling and the active power output. The system, modeled in PScad environment, allows to verify the response of the renewables-based generators with VSM control in the presence of a fault in the grid.
Thermodynamics of a Phase-Driven Proximity Josephson Junction
2019
We study the thermodynamic properties of a superconductor/normal metal/superconductor Josephson junction {in the short limit}. Owing to the proximity effect, such a junction constitutes a thermodynamic system where {phase difference}, supercurrent, temperature and entropy are thermodynamical variables connected by equations of state. These allow conceiving quasi-static processes that we characterize in terms of heat and work exchanged. Finally, we combine such processes to construct a Josephson-based Otto and Stirling cycles. We study the related performance in both engine and refrigerator operating mode.
Progettazione, realizzazione e caratterizzazione di un Generatore Lineare Tubolare a Magneti Permanenti per lo sfruttamento del moto ondoso marino
Design criteria of tubular linear induction motors and generators: A prototype realization and its characterization
2013
In this paper a mathematical model of tubular linear induction machines (TLIM) with hollowed induced part is recalled. Moreover the design criteria of a TLIM with hollowed iron induced part are presented as well as the technological processes to be adopted and the choice of materials to construct the various parts. The methodologies for mechanical assembling and electric wiring are considered too. A prototype with bimetallic induced part has been designed and built. Finally some experimental results on electrical and mechanical variables, when the machines are used as motors, are shown.