Search results for "Telecommunication"
showing 10 items of 1769 documents
Review of information and communication technologies for smart micro-grid automation
2017
The growing challenges of Smart Micro-Grid can only be met if secure and fast information and communication technology (ICT) solutions are developed. In this paper, some of the ICT techniques are reviewed for smart micro-grid automation. Firstly, an overview of the role of ICT in grid distribution is explained with respect to electricity value chain in power distribution. Further, each domain in the value chain is analyzed with respect to ICT applications in power generation, transmission, distribution and consumption. ICT stands as a prominent driving force to enhance trustworthiness, security, and productivity of the power distribution through information exchange, regulated generation, d…
Random Slicing: Efficient and Scalable Data Placement for Large-Scale Storage Systems
2014
The ever-growing amount of data requires highly scalable storage solutions. The most flexible approach is to use storage pools that can be expanded and scaled down by adding or removing storage devices. To make this approach usable, it is necessary to provide a solution to locate data items in such a dynamic environment. This article presents and evaluates the Random Slicing strategy, which incorporates lessons learned from table-based, rule-based, and pseudo-randomized hashing strategies and is able to provide a simple and efficient strategy that scales up to handle exascale data. Random Slicing keeps a small table with information about previous storage system insert and remove operations…
Aperiodic Diffract: Study of diffraction gratings
2014
In this work we introduce a virtual laboratory, APERIODIC DIFFRACT, developed in Matlab GUI (Graphical User Interface) as an informatics tool for teaching the diffractive properties of aperiodic gratings. This GUI allows the student to generate aperiodic sequences by iterating and lets to study the spectra for different iterating orders.<br /><br />
Wideband THz time domain spectroscopy based on optical rectification and electro-optic sampling
2013
We present an analytical model describing the full electromagnetic propagation in a THz time-domain spectroscopy (THz-TDS) system, from the THz pulses via Optical Rectification to the detection via Electro Optic-Sampling. While several investigations deal singularly with the many elements that constitute a THz-TDS, in our work we pay particular attention to the modelling of the time-frequency behaviour of all the stages which compose the experimental set-up. Therefore, our model considers the following main aspects: (i) pump beam focusing into the generation crystal; (ii) phase-matching inside both the generation and detection crystals; (iii) chromatic dispersion and absorption inside the c…
Muon identification with the ATLAS Tile Calorimeter Read-Out Driver for Level-2 trigger purposes
2008
The Hadronic Tile Calorimeter (TileCal) at the ATLAS experiment is a detector made out of iron as passive medium and plastic scintillating tiles as active medium. The light produced by the particles is converted to electrical signals which are digitized in the front-end electronics and sent to the back-end system. The main element of the back-end electronics are the VME 9U Read-Out Driver (ROD) boards, responsible of data management, processing and transmission. A total of 32 ROD boards, placed in the data acquisition chain between Level-1 and Level-2 trigger, are needed to read out the whole calorimeter. They are equipped with fixed-point Digital Signal Processors (DSPs) that apply online …
Information potential for some probability density functions
2021
Abstract This paper is related to the information theoretic learning methodology, whose goal is to quantify global scalar descriptors (e.g., entropy) of a given probability density function (PDF). In this context, the core concept is the information potential (IP) S [ s ] ( x ) : = ∫ R p s ( t , x ) d t , s > 0 of a PDF p(t, x) depending on a parameter x; it is naturally related to the Renyi and Tsallis entropies. We present several such PDF, viewed also as kernels of integral operators, for which a precise relation exists between S[2](x) and the variance Var[p(t, x)]. For these PDF we determine explicitly the IP and the Shannon entropy. As an application to Information Theoretic Learning w…
Capabilities of Ultrametric Automata with One, Two, and Three States
2016
Ultrametric automata use p-adic numbers to describe the random branching of the process of computation. Previous research has shown that ultrametric automata can have a significant decrease in computing complexity. In this paper we consider the languages that can be recognized by one-way ultrametric automata with one, two, and three states. We also show an example of a promise problem that can be solved by ultrametric integral automaton with three states.
Some properties of vertex-oblique graphs
2016
The type t G ( v ) of a vertex v ? V ( G ) is the ordered degree-sequence ( d 1 , ? , d d G ( v ) ) of the vertices adjacent with v , where d 1 ? ? ? d d G ( v ) . A graph G is called vertex-oblique if it contains no two vertices of the same type. In this paper we show that for reals a , b the class of vertex-oblique graphs G for which | E ( G ) | ? a | V ( G ) | + b holds is finite when a ? 1 and infinite when a ? 2 . Apart from one missing interval, it solves the following problem posed by Schreyer et?al. (2007): How many graphs of bounded average degree are vertex-oblique? Furthermore we obtain the tight upper bound on the independence and clique numbers of vertex-oblique graphs as a fun…
Lehmer code transforms and Mahonian statistics on permutations
2012
Abstract In 2000 Babson and Steingrimsson introduced the notion of vincular patterns in permutations. They show that essentially all well-known Mahonian permutation statistics can be written as combinations of such patterns. Also, they proved and conjectured that other combinations of vincular patterns are still Mahonian. These conjectures were proved later: by Foata and Zeilberger in 2001, and by Foata and Randrianarivony in 2006. In this paper we give an alternative proof of some of these results. Our approach is based on permutation codes which, like the Lehmer code, map bijectively permutations onto subexcedant sequences. More precisely, we give several code transforms (i.e., bijections…
Enumerating the Walecki-Type Hamiltonian Cycle Systems
2017
Let Kv be the complete graph on v vertices. A Hamiltonian cycle system of odd order v (briefly HCS(v)) is a set of Hamiltonian cycles of Kv whose edges partition the edge set of Kv. By means of a slight modification of the famous HCS(4n+1) of Walecki, we obtain 2n pairwise distinct HCS(4n+1) and we enumerate them up to isomorphism proving that this is equivalent to count the number of binary bracelets of length n, i.e. the orbits of Dn, the dihedral group of order 2n, acting on binary n-tuples.