subregion using an embedded GPS or a location discovery algorithm. After that,
all the sensors collect position coordinates, remaining energy, sensor node ID,
and the number of their one-hop live neighbors during the information exchange.
-\textcolor{blue}{Both INFO packet and ActiveSleep packet contain two parts: header and data payload. The sensor ID is included in the header, where the header size is 8 bits. The data part includes position coordinates (64 bits), remaining energy (32 bits), and the number of one-hop live neighbors (8 bits). Therefore the size of the INFO packet is 112 bits. The ActiveSleep packet is 16 bits size, 8 bits for the header and 8 bits for data part that includes only sensor status (0 or 1).}
+\textcolor{green}{Both INFO packet and ActiveSleep packet contain two parts: header and data payload. The sensor ID is included in the header, where the header size is 8 bits. The data part includes position coordinates (64 bits), remaining energy (32 bits), and the number of one-hop live neighbors (8 bits). Therefore the size of the INFO packet is 112 bits. The ActiveSleep packet is 16 bits size, 8 bits for the header and 8 bits for data part that includes only sensor status (0 or 1).}
The sensors inside a same region cooperate to elect a leader. The selection
criteria for the leader are (in order of priority):
\begin{enumerate}
sensing period~$p$, $R$ is the number of subregions, and $|J|$ is the number
of sensors in the network.
-\item {\bf \textcolor{blue}{Energy Saving Ratio (ESR)}}:
-\textcolor{blue}{this metric, which shows the ability of a protocol to save energy, is defined by:
+\item {\bf \textcolor{green}{Energy Saving Ratio (ESR)}}:
+\textcolor{green}{this metric, which shows the ability of a protocol to save energy, is defined by:
\begin{equation*}
\scriptsize
\mbox{ESR}(\%) = \frac{\mbox{Number of alive sensors during this round}}
\label{figure6}
\end{figure}
-\subsubsection{\textcolor{blue}{Energy Saving Ratio (ESR)}}
-
-%\textcolor{blue}{In this experiment, we study the energy saving ratio, see Figure~\ref{fig5}, for 200 deployed nodes.
-%The larger the ratio is, the more redundant sensor nodes are switched off, and consequently the longer the network may liv%e. }
-
-\textcolor{blue}{The simulation results show that our protocol PeCO allows to
- efficiently save energy by turning off some sensors during the sensing phase.
- As shown in Figure~\ref{fig5}, GAF provides better energy saving than PeCO for
- the first fifty rounds, because GAF balances the energy consumption among
- sensor nodes inside each small fixed grid and thus permits to extend the life of
- sensors in each grid fairly but in the same time turn on large number of
- sensors during sensing that lead later to quickly deplete sensor's batteries
- together. After that GAF provide less energy saving compared with other
- approaches because of the large number of dead nodes. DESK algorithm shows less
- energy saving compared with other approaches due to activate a large number of
- sensors during the sensing. DiLCO protocol provides less energy saving ratio
- compared with PeCO because it generally activate a larger number of sensor
- nodes during sensing. Note that again as the number of rounds increases PeCO
- becomes the most performing one, since it consumes less energy compared with
- other approaches.}
+\subsubsection{\textcolor{green}{Energy Saving Ratio}}
+
+
+\textcolor{green}{The simulation results show that our protocol PeCO saves
+ efficiently energy by turning off some sensors during the sensing phase. As
+ shown in Figure~\ref{fig5}, GAF provides better energy saving than PeCO for
+ the first fifty rounds. Indeed GAF balances the energy consumption among
+ sensor nodes inside each small fixed grid and thus permits to extend the life
+ of sensors in each grid fairly. However, at the same time it turns on a large
+ number of sensors and that leads later to quickly deplete sensor's batteries.
+ DESK algorithm shows less energy saving compared with other approaches. In
+ comparison with PeCO, DiLCO protocol usually provides lower energy saving
+ ratios. Moreover, it can be noticed that after round fifty, PeCO protocol
+ exhibits the slowest decrease among all the considered protocols.}
\begin{figure}[h!]
%\centering
\includegraphics[scale=0.5]{ESR.eps} %\\~ ~ ~(a)
\caption{Energy Saving Ratio for 200 deployed nodes}
\label{fig5}
-\end{figure}
-
-
+\end{figure}
\subsubsection{Energy Consumption}
Protocol/85, Protocol/90, and Protocol/95 the amount of time during which the
network can satisfy an area coverage greater than $70\%$, $80\%$, $85\%$,
$90\%$, and $95\%$ respectively, where the term Protocol refers to DiLCO or
-PeCO. \textcolor{blue}{Indeed there are applications that do not require a 100\% coverage of the
+PeCO. \textcolor{green}{Indeed there are applications that do not require a 100\% coverage of the
area to be monitored. For example, forest
fire application might require complete coverage
in summer seasons while only require 80$\%$ of the area to be covered in rainy seasons~\citep{li2011transforming}. As another example, birds habit study requires only 70$\%$-coverage at nighttime when the birds are sleeping while requires 100$\%$-coverage at daytime when the birds are active~\citep{1279193}.
-%Mudflows monitoring applications may require part of the area to be covered in sunny days. Thus, to extend network lifetime, the coverage quality can be decreased if it is acceptable~\citep{wang2014keeping}}.
PeCO always outperforms DiLCO for the three lower coverage ratios, moreover the
-improvements grow with the network size. DiLCO outperforms PeCO when the coverage ratio is required to be $>90\%$, but PeCo extends the network lifetime significantly when coverage ratio can be relaxed.}
-%DiLCO is better for coverage ratios near 100\%, but in that case PeCO is not ineffective for the smallest network sizes.
+improvements grow with the network size. DiLCO outperforms PeCO when the coverage ratio is required to be $>90\%$, but PeCO extends the network lifetime significantly when coverage ratio can be relaxed.}
\begin{figure}[h!]
\centering \includegraphics[scale=0.55]{figure9.eps}
