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Network Vulnerability to Single, Multiple, and Probabilistic Physical Attacks
"... Abstract—Telecommunications networks heavily rely on the physical infrastructure and, are therefore, vulnerable to natural disasters, such as earthquakes or floods, as well as to physical attacks, such as an Electromagnetic Pulse (EMP) attack. Largescale disasters are likely to destroy network equip ..."
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Cited by 6 (3 self)
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Abstract—Telecommunications networks heavily rely on the physical infrastructure and, are therefore, vulnerable to natural disasters, such as earthquakes or floods, as well as to physical attacks, such as an Electromagnetic Pulse (EMP) attack. Largescale disasters are likely to destroy network equipment and to severely affect interdependent systems such as the powergrid. In turn, longterm outage of the powergrid might cause additional failures to the telecommunication network. In this paper, we model an attack as a disk around its epicenter, and provide efficient algorithms to find vulnerable points within the network, under various metrics. In addition, we consider the case in which multiple disasters happen simultaneously and provide an approximation algorithm to find the points which cause the most significant destruction. Finally, since a network element does not always fail, even when it is close to the attack’s epicenter, we consider a simple probabilistic model in which the probability of a network element failure is given. Under this model, we tackle the cases of single and multiple attacks and develop algorithms that identify potential points where an attack is likely to cause a significant damage. Index Terms—Network survivability, geographic networks, network design, Electromagnetic Pulse (EMP), computational geometry. I.
A New Solution to the Simultaneous Localisation and Map Building (SLAM) Problem
, 2005
"... The proposition posed by the problem of simultaneous localisation and map building (SLAM) is whether a mobile robot can be placed in an unknown environment and then incrementally build a map of this environment, while using the map to determine its globally referenced pose. The various solutions to ..."
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Cited by 1 (0 self)
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The proposition posed by the problem of simultaneous localisation and map building (SLAM) is whether a mobile robot can be placed in an unknown environment and then incrementally build a map of this environment, while using the map to determine its globally referenced pose. The various solutions to the SLAM problem that have been proposed so far, such as the extended Kalman filter (EKF), are typically highly theoretical and require rigorous modeling of the robot's locomotion mechanism, sensor errors and the environment. These motifs have encouraged a long string of simplifying and often wishful assumptions, which invariably restrict the application of SLAM to only a contrived figment of the real world. While using a plethora of assumptions may be academically acceptable, a change of tack is needed for realworld operation. In this paper, a novel SLAM solution is proposed that is based on perpetually solving the kidnapped robot problem. By doing so, the locomotive specifics of the robot are irrelevant and, hence, the robot can be engineered to be as flexible and robust as practicable without contemplating the possible side effects on odometric accuracy and associated measurement drift. While the proposed solution does not require odometry (nor does it assume motion continuity), it makes provisions for the inclusion of such information, in possible combination with inertial sensors, to improve the system's performance while not compromising its generality. The solution comprises a multiplehypothesis data association algorithm for recognising map landmarks perceived from different viewpoints, and a simple relative error algorithm for representing and handling the positional uncertainties of the robot and landmarks. The latter algorithm is based on the sole premise that the positional uncertainty is directly proportional to the radial distance from the origin. This paper argues that the proposed solution, while atypical, facilitates navigation in natural environments. Practical results from several outdoor experimental trials will be published shortly.
Par courier: By mail: Ecole Nationale Supérieure des Mines de SaintEtienne
, 2007
"... 2007500010 Les rapports de recherche ..."
Moving Target Travelling Salesman Problem using Genetic Algorithm
"... In this paper, the Moving Target Travelling Salesman Problem (MTTSP) is described. In MTTSP, several sites are required to be visited which are moving with constant velocity in different directions. The distance of the sites from origin, velocity and the angle of movement are known in advance. The g ..."
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In this paper, the Moving Target Travelling Salesman Problem (MTTSP) is described. In MTTSP, several sites are required to be visited which are moving with constant velocity in different directions. The distance of the sites from origin, velocity and the angle of movement are known in advance. The goal is to find the fastest tour starting and ending at the origin which intercepts all the sites. The method implemented using genetic algorithm approach on the various data sets and the results are compared with greedy approach.
Multilevel Approaches applied to the Capacitated Clustering Problem
"... Abstract This paper presents two multilevel refinement algorithms for the capacitated clustering problem. Multilevel refinement is a collaborative technique capable of significantly aiding the solution process for optimisation problems. The central methodologies of the technique are filtering solut ..."
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Abstract This paper presents two multilevel refinement algorithms for the capacitated clustering problem. Multilevel refinement is a collaborative technique capable of significantly aiding the solution process for optimisation problems. The central methodologies of the technique are filtering solutions from the search space and reducing the level of problem detail to be considered at each level of the solution process. The first multilevel algorithm uses a simple tabu search while the other executes a standard local search procedure. Both algorithms demonstrate that the multilevel technique is capable of aiding the solution process for this combinatorial optimisation problem.