Search results for " Mathematics"
showing 10 items of 10797 documents
Variable neighborhood descent for the incremental graph drawing
2017
Abstract Graphs are used to represent reality in several areas of knowledge. Drawings of graphs have many applications, from project scheduling to software diagrams. The main quality desired for drawings of graphs is readability, and crossing reduction is a fundamental aesthetic criterion for a good representation of a graph. In this paper we target the edge crossing reduction in the context of incremental graph drawing, in which we want to preserve the layout of a graph over successive drawings. We propose a hybrid method based on the GRASP (Greedy Randomized Adaptive Search Procedure) and VND (Variable Neighborhood Descent) methodologies and compare it with previous methods via simulation.
The regression Tsetlin machine: a novel approach to interpretable nonlinear regression
2019
Relying simply on bitwise operators, the recently introduced Tsetlin machine (TM) has provided competitive pattern classification accuracy in several benchmarks, including text understanding. In this paper, we introduce the regression Tsetlin machine (RTM), a new class of TMs designed for continuous input and output, targeting nonlinear regression problems. In all brevity, we convert continuous input into a binary representation based on thresholding, and transform the propositional formula formed by the TM into an aggregated continuous output. Our empirical comparison of the RTM with state-of-the-art regression techniques reveals either superior or on par performance on five datasets. Thi…
Kick Detection and Influx Size Estimation during Offshore Drilling Operations using Deep Learning
2019
An uncontrolled or unobserved influx or kick during drilling has the potential to induce a well blowout, one of the most harmful incidences during drilling both in regards to economic and environmental cost. Since kicks during drilling are serious risks, it is important to improve kick and loss detection performance and capabilities and to develop automatic flux detection methodology. There are clear patterns during a influx incident. However, due to complex processes and sparse instrumentation it is difficult to predict the behaviour of kicks or losses based on sensor data combined with physical models alone. Emerging technologies within Deep Learning are however quite adapt at picking up …
Infarctus du myocarde au cours de l’artérite à cellules géantes : étude de cohorte
2020
Introduction Le risque d’evenement cardiovasculaire est accru au cours de l’arterite a cellules geantes (ACG), en particulier dans les premiers mois suivant le diagnostic de la vascularite [1] . L’objectif de ce travail etait de decrire les caracteristiques des infarctus du myocarde (IDM) survenant chez des patients atteints d’ACG et de les comparer avec des IDM survenant chez des patients ne presentant pas d’ACG au moment de leur IDM. Patients et methodes Les patients atteints d’ACG ont ete identifies parmi la liste des biopsies d’artere temporale (BAT) qui montraient des lesions d’ACG et qui avaient ete analysees entre le 1er janvier 2001 et le 31 decembre 2016 dans les deux laboratoires …
Meridianos distintos (Jīng Bié) y sistema linfático, comparación anatómica y funcional
2016
The analysis of possible meeting points between Chinese and Western medicine makes an addition to the gradual progress towards mutual understanding and synergy of both disciplines. The description of trajectories and functions of the Divergent Channels seems to suggest certain parallels regarding western anatomy and lymph system function. From the anatomical perspective, the trajectory of the JīngBie resembles the arrangement and energy flux direction to the lymph system. Besides, the position of the main JīngBie points, such as “Departure points” and “Window of Heaven points” tends to match regions with a high presence of lymph nodes. Also, the JīngBie functions resemble the physiology of …
Diagramme mit ggplot2
2020
Mit dem Zusatzpaket ggplot2 lassen sich die in Kap. 14 vorgestellten Diagrammtypen ebenfalls erstellen. Dabei ist die Herangehensweise eine grundsatzlich andere: Wahrend der Basisumfang von R fur verschiedene Diagrammarten einzelne Funktionen bereitstellt, werden mit ggplot2 alle Diagrammtypen mit einem einheitlichen System erzeugt. Sind Diagramme des Basisumfangs analog zu einer Leinwand, auf der jede Funktion spater nicht mehr anderbare Elemente aufmalt, reprasentiert ggplot2 alle Diagrammelemente explizit in einem Objekt. Erstellte Diagramme lassen sich uber dieses Objekt weiter verandern, an Funktionen ubergeben und speichern.
Constructing Antidictionaries of Long Texts in Output-Sensitive Space
2021
AbstractA wordxthat is absent from a wordyis calledminimalif all its proper factors occur iny. Given a collection ofkwordsy1, … ,ykover an alphabetΣ, we are asked to compute the set$\mathrm {M}^{\ell }_{\{y_1,\ldots ,y_k\}}$M{y1,…,yk}ℓof minimal absent words of length at mostℓof the collection {y1, … ,yk}. The set$\mathrm {M}^{\ell }_{\{y_1,\ldots ,y_k\}}$M{y1,…,yk}ℓcontains all the wordsxsuch thatxis absent from all the words of the collection while there existi,j, such that the maximal proper suffix ofxis a factor ofyiand the maximal proper prefix ofxis a factor ofyj. In data compression, this corresponds to computing the antidictionary ofkdocuments. In bioinformatics, it corresponds to c…
Recentrifuge: Robust comparative analysis and contamination removal for metagenomics
2017
Metagenomic sequencing is becoming widespread in biomedical and environmental research, and the pace is increasing even more thanks to nanopore sequencing. With a rising number of samples and data per sample, the challenge of efficiently comparing results within a specimen and between specimens arises. Reagents, laboratory, and host related contaminants complicate such analysis. Contamination is particularly critical in low microbial biomass body sites and environments, where it can comprise most of a sample if not all. Recentrifuge implements a robust method for the removal of negative-control and crossover taxa from the rest of samples. With Recentrifuge, researchers can analyze results f…
On the continuous and discontinuous maximal operators
2018
Abstract In the first part of this paper we study the regularity properties of a wide class of maximal operators. These results are used to show that the spherical maximal operator is continuous W 1 , p ( R n ) ↦ W 1 , p ( R n ) , when p > n n − 1 . Other given applications include fractional maximal operators and maximal singular integrals. On the other hand, we show that the restricted Hardy–Littlewood maximal operator M λ , where the supremum is taken over the cubes with radii greater than λ > 0 , is bounded from L p ( R n ) to W 1 , p ( R n ) but discontinuous.
Biological investigation of neural circuits in the insect brain
2018
Watching insects thoughtfully one cannot but adore their behavioural capabilities. They have developed amazing reproductive, foraging and orientation strategies and at the same time they followed the evolutionary path of miniaturization and sparseness. Both features together turn them into a role model for autonomous robots. Despite their tiny brains, fruit flies (Drosophila) can orient, walk on uneven terrain, in any orientation to gravity, can fly in adverse winds, find partners, places for egg laying, food and shelter. Drosophila melanogaster is the model animal for geneticists and cutting-edge tools are being continuously developed to study the underpinnings of their behavioural capabil…