## 6 Numerical Results
\begin{table}
\begin{tabular}{c c c} \hline \hline
**System \& Network Parameters** & **Definition** & **Value** \\ \hline \(N_{node}\) & Number of nodes & 100 \\ \(M\) & Network Size (m\({}^{3}\)) & \(250\times 250\times 250\) \\ \(h\) & Network Depth (m) & 250 \\ \(S_{(x,y,z)}\) & Sink Location & (125, 125, 0) \\ \(T_{round}\) & Round Duration (s) & 100 \\ \hline \multicolumn{3}{c}{**Channel \& Modern Parameters**} \\ \hline R & Data rate (kbps) & 2 \\ \(E_{0}\) & Initial Energy (kJ) & 0.1 \\ \(p_{rx}\) & Reception Power (W) & 1.3 \\ \(p_{dalle}\) & Idle Power (mW) & 2.5 \\ \(f\) & Frequency (kHz) & 25 \\ \(p_{ij}^{b}\) & Bit error rate on link-(i,j) & \(10^{-10}\) \\ L & Packet size in frames (bits) & 1024 \\ \(\kappa\) & Spreading Factor & 1.5 \\ \(B_{N}\) & Noise Bandwidth (kHz) & 1 \\ \(E_{DA}\) & Data Aggregation Energy & 5 \\ \multicolumn{3}{c}{(nJ/bit/packet)} \\ \hline \multicolumn{3}{c}{**Stochastic Energy Harvesting**} \\ \multicolumn{3}{c}{**Model Parameters**} \\ \hline \(L\) & Cantilever length (mm) & 50 \\ \(B\) & Cantilever width (mm) & 3 \\ \(\varepsilon_{r}\) & Relative permittivity & 4000 \\ \(\varepsilon_{0}\) & Absolute permittivity (F/m) & \(8.85\times 10^{-12}\) \\ \(T_{p2t}\) & Thickness (um) & 60 \\ \(d_{31}^{p}\) & Piezoelectric constant (C/N) & \(300\times 10^{-12}\) \\ \(\xi_{t}\) & Strouhal number & 0.2 \\ \(v_{f}\) & Mean Flow Velocity (m/s) & 0.65 \\ \(\rho\) & Density of Ocean Water(kg/m\({}^{3}\)) & 1000 \\ \(\lambda\) & Mean event rate & 5 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Simulation Parameters. Figure 4: Number of data signals received at the gateway per energy. is collected while nodes await idle and harvest energy until their communication slots in the cluster. Compared to the TDMA-none method, in TDMA-EH and TDMA-RL, as more nodes remain active in rounds, 21% and 37% more data packets can be relayed to the gateway, respectively. The TDMA-RL and TDMA-EH curves have the same characteristics, but they collect more energy in successive rounds. On the other hand, the TDMA-RL curve outperforms by selecting efficient slots to remain idle, observing the ambient available energy, selecting the most inefficient time slot in terms of available energy, and performing data transmission. Consequently, TDMA-RL captures more energy, whereas the TDMA-EH method neglects to exploit available energy by transmitting data during periods of high energy availability in time slots. Figure 6 shows the number of available nodes over data signals received at the base station. As more energy is captured from environment, lifetime duration of nodes is improved and more data can be generated compared to TDMA-EH utilizing traditional TDMA approach. In TDMA slots, nodes communicate with their cluster heads without being aware of their ambient energy conditions. Therefore, less ambient energy can be collected. In the early phase of the simulation, it is observed that three methods have the same decrease rate in the number of alive nodes until 5% of nodes run out of energy and a few megabytes of data are received at the base station. It is observed that if energy harvesting (EH) is involved in the system, the amount of data packet reception increases by 23% regardless of the medium access method. It is clear that harvested energy significantly contributes to the battery of nodes in successive rounds; hence, nodes can perform more data transmission. The TDMA-RL curve improves the amount of data packets by 11% compared to the TDMA-EH method. We present the comparison of total harvested energy in the system in Figure 7. The TDMA-Best curve represents the maximum total energy captured by all nodes in the system, assuming nodes know the least efficient transmission slots to harvest energy in advance. This curve serves as an upper bound for the total energy available in the environment. Since energy harvesting is not incorporated in the TDMA-none method, we compare the TDMA-EH and TDMA-RL methods with this upper bound of available energy.