Search results for "Vector"

Evaluating a bound for MANETs routing protocols performance using graphs with activation windows

2008

In this paper we present an algorithm called STPA (shortest time path algorithm) which aims at providing a comparison tool for the evaluation of a bound for mobile ad hoc networks (MANETs) routing protocols performance. STPA provides an exhaustive evaluation of an ideal routing protocol. Based on the current position and state of the nodes it can determine factors like: how many complete messages get to the destination, which is the smallest amount of time required by a packet to get to the destination, which path followed each packet, and so on. This values would allow a protocol designer to improve or fine tune his proposal. We demonstrate that the complexity of the algorithm is O(sigma2)…

A new way of achieving multi-path routing in wireless networks

2020

In the 21st century, the wireless technology is still developing rapidly and trying to be 'Faster, Higher, and Stronger': faster data rate, higher bandwidth and stronger connectivity. Wireless Mesh Networks (WMN) have been envisioned as an important solution to the next generation wireless networking which can be used in wireless community networks, wireless enterprise networks, transportation systems, home networking and last-mile wireless internet access. They also provide a cheap, quick and effective way for building wireless data networks. Considering the nature of these networks, routing is a key process for operating the WMN. This paper proposes a new way of creating multi-path routin…

A hybrid bio-inspired approach to solving the routing problem in mobile ad hoc networks

2018

A mobile ad hoc network (MANET) is an autonomous system of mobile hosts (nodes) connected by a wireless link. However, the problem of designing routing protocols poses challenges to researchers due to the unpredictable and dynamic nature of ad hoc networks. Hence, bio-inspired algorithms are widely used to design adaptive routing strategies for MANETs. This paper proposes a routing protocol based on the hybridisation of ant colony optimisation (ACO) and 2-opt heuristic with the optimisation of ACO parameters. Given the vast scope of the parameters, a genetic algorithm is used to minimise the complexity of the problem. The implementation of the method is realised by MATLAB. To valid the resu…

Positioning Error Prediction and Training Data Evaluation in RF Fingerprinting Method

2019

Radio Frequency (RF) fingerprinting-based localization has become a research interest due to its minimum hardware requirement and satisfiable positioning accuracy. However, despite the significant attention this topic has gained, most of the research focused on the calculation of position estimates. In this paper, we propose a simple and novel method that can be used as an indicator of fingerprinting positioning error. The method is based on cluster radius evaluation of multiple fingerprinting data during the test phase, which can be used by a Location Based Service (LBS) provider to predict the user position estimation accuracy. This method can be used effectively in real-time to predict t…

Bezier curves approximation of triangularized surfaces using SVG

2006

This paper presents a technique to convert surfaces, obtained through a Data Dependent Triangulation, in Bezier Curves by using a Scalable Vector Graphics File format. The method starts from a Data Dependent Triangulation, traces a map of the boundaries present into the triangulation, using the characteristics of the triangles, then the estimated barycenters are connected, and a final conversion of the resulting polylines in curves is performed. After the curves have been estimated and closed the final representation is obtained by sorting the surfaces in a decreasing order. The proposed techniques have been compared with other raster to vector conversions in terms of perceptual quality.

Advanced SVG Rendering of Digital Images

2005

Automatic Conversion Technique from Data Dependent Triangulation to SVG B-Splines

2005

Stable products of spheres in the non-linear coupling of oscillators or quasi-periodic motions

2004

Abstract For generic families of vector fields or transformations, normally hyperbolic invariant products of spheres appear near partially elliptic rest points. To cite this article: M. Kammerer-Colin de Verdiere, C. R. Acad. Sci. Paris, Ser. I 339 (2004).

Novel Glutamate–Putrescine Ligase Activity in Haloferax mediterranei: A New Function for glnA-2 Gene

2021

This article belongs to the Section Cellular Biochemistry.

A genetic algorithm approach to purify the classifier training labels for the analysis of remote sensing imagery

2017

This paper proposes a Genetic Algorithm (GA) approach to clean a given classifier training set for remote sensing image analysis. Starting from an initial set of training data, the new method called GA-Training Label Purifying (GA-TLP) consists of the significant training sample selection using GAs in order to maximize the classifier accuracy. This means to retain the most informative samples and to remove the uncertain, redundant, and misclassified ones. As a result of the selection process, we can obtain a purified training set. The proposed model is implemented and evaluated using a LANDSAT 7 ETM+ image. The experimental results confirm the effectiveness of the proposed approach.