From: Karine Deschinkel Date: Mon, 13 Oct 2014 12:55:27 +0000 (+0200) Subject: modif related work de Michel X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/Sensornets15.git/commitdiff_plain/8289f9fca3236b8d7083fd54b8e33d8dcd1220a2?ds=inline modif related work de Michel --- diff --git a/Example.tex b/Example.tex index 702d24b..ac05f6c 100644 --- a/Example.tex +++ b/Example.tex @@ -124,14 +124,14 @@ and barrier coverage \cite{Kumar:2005}\cite{kim2013maximum} to prevent intrude The major approach to extend network lifetime while preserving coverage is to divide/organize the sensors into a suitable number of set covers (disjoint or -non-disjoint) where each set completely covers a region of interest and to +non-disjoint), where each set completely covers a region of interest, and to activate these set covers successively. The network activity can be planned in advance and scheduled for the entire network lifetime or organized in periods, and the set of active sensor nodes is decided at the beginning of each period \cite{ling2009energy}. Active node selection is determined based on the problem requirements (e.g. area monitoring, connectivity, power efficiency). For instance, Jaggi et al. \cite{jaggi2006} -adress the problem of maximizing network lifetime by dividing sensors into the maximum number of disjoint subsets such that each subset can ensure both coverage and connectivity. A greedy algorithm is applied once to solve this problem and the computed sets are activated in succession to achieve the desired network lifetime. -Vu \cite{chin2007}, Padmatvathy et al \cite{pc10}, propose algorithms working in a periodic fashion where a cover set is computed at the beginning of each period. +address the problem of maximizing network lifetime by dividing sensors into the maximum number of disjoint subsets such that each subset can ensure both coverage and connectivity. A greedy algorithm is applied once to solve this problem and the computed sets are activated in succession to achieve the desired network lifetime. +Vu \cite{chin2007}, Padmatvathy et al. \cite{pc10}, propose algorithms working in a periodic fashion where a cover set is computed at the beginning of each period. {\it Motivated by these works, DiLCO protocol works in periods, where each period contains a preliminary phase for information exchange and decisions, followed by a sensing phase where one cover set is in charge of the sensing task.} @@ -146,11 +146,11 @@ cooperatively by communicating with their neighbors which of them will remain in sleep mode for a certain period of time. The centralized algorithms~\cite{cardei2005improving,zorbas2010solving,pujari2011high} always provide nearly or close to optimal solution since the algorithm has global view -of the whole network, but such a method has the disadvantage of requiring high +of the whole network. But such a method has the disadvantage of requiring high communication costs, since the node (located at the base station) making the decision needs information from all the sensor nodes in the area and the amount of information can be huge. {\it In order to be suitable for large-scale network, in the DiLCO protocol, the area coverage is divided into several smaller - subregions, and in each of which, a node called the leader is on charge for + subregions, and in each of one, a node called the leader is in charge for selecting the active sensors for the current period.} A large variety of coverage scheduling algorithms have been developed. Many of