# Development and Evaluation of a Fluctuating Plume Model for Odor Impact Assessment
## 4 Results and Discussions
### Mean Concentration  
The first result obtained from the model is the average concentration, obtained with Equation (16). \(C_{m}\) values were calculated for each sampling position of each crossbar, for each trial. A total of 132 values were collected from the model. These values were compared with experimental 10-min data measurements. As mentioned in the field experiment document [56], measurements taken from deflated bag were considered unreliable and were removed from the comparison. To evaluate the quality of the model, performance parameters and some graphs are presented. Table 4 shows the results obtained from the performance evaluation: it is worth to remark that 72% of the values lies within a factor of 2 of the observations (_FAC2_). Moreover, parameters like MB and NMB are very close to the ideal zero value.  
A scatter plot was then drawn to help the reading of the results (Figure 3): it reports the simulated values (\(y\)-axis) of \(C_{m}\), plotted towards the field data (\(x\)-axis). The bisector (1:1), representing a perfect model, and the two lines of _FAC2_ (1:0.5, 1:2) representing a  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Trials** & \(\overline{O_{i}}\) & \(MB\) & \(NMB\) & \(RMSE\) & \(NMSE\) & \(IOA\) & _FAC2_ \\ \hline All cases (B-L) & 5.6 & \(-\)0.2 & \(-\)0.03 & 4.5 & 0.7 & 0.88 & 72\% \\ \hline \hline \end{tabular}
\end{table}
Table 4: Parameters for the performance evaluation of the mean concentrations.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Trial** & **Receptor** & \(C_{m}\) & \(C_{max}\) & \(\sigma_{c}\) & \(I_{c}\) & \(C_{90}\) & \(R_{90}\) \\ \hline  & & (ug/m\({}^{3}\)) & (ug/m\({}^{3}\)) & (ug/m\({}^{3}\)) & & (ug/m\({}^{3}\)) & \\ \hline B & T1P5 & 0.01 & 0.09 & 0.02 & 1.98 & 0.0 & 3.1 \\  & T2P4 & 1.13 & 7.36 & 1.76 & 1.56 & 3.7 & 3.2 \\ C & T1P5 & 8.64 & 27.02 & 6.63 & 0.77 & 18.4 & 2.1 \\  & T2P4 & 9.13 & 16.67 & 3.54 & 0.39 & 13.2 & 1.4 \\ D & T1P3 & 0.01 & 0.04 & 0.01 & 1.60 & 0.0 & 3.3 \\  & T2P3 & 0.02 & 0.04 & 0.02 & 0.85 & 0.0 & 1.9 \\ E & T1P3 & 9.30 & 30.91 & 7.03 & 0.76 & 18.0 & 1.9 \\  & T2P2 & 2.53 & 12.17 & 3.54 & 1.40 & 8.0 & 3.2 \\ F & T1P2 & 13.70 & 36.39 & 8.75 & 0.64 & 25.1 & 1.8 \\  & T2P2 & 6.79 & 16.92 & 4.37 & 0.64 & 12.8 & 1.9 \\ G & T1P2 & 15.69 & 41.32 & 11.66 & 0.74 & 29.9 & 1.9 \\  & T2P2 & 7.02 & 17.40 & 4.25 & 0.61 & 13.3 & 1.9 \\ H & T1P4 & 3.41 & 36.15 & 7.40 & 2.17 & 11.0 & 3.2 \\  & T2P3 & 5.44 & 21.72 & 6.33 & 1.16 & 15.0 & 2.7 \\ I & T1P4 & 6.18 & 28.66 & 6.86 & 1.11 & 16.0 & 2.6 \\  & T1P9 & 4.58 & 31.52 & 7.46 & 1.63 & 16.4 & 3.6 \\ J & T1P4 & 3.24 & 26.29 & 5.92 & 1.83 & 6.9 & 2.1 \\  & T1P8 & 8.47 & 36.09 & 8.63 & 1.02 & 20.1 & 2.4 \\ K & T1P4 & 6.27 & 36.57 & 7.77 & 1.24 & 14.9 & 2.4 \\  & T1P9 & 5.56 & 34.08 & 7.55 & 1.36 & 14.5 & 2.6 \\ L & T1P4 & 0.76 & 8.15 & 1.15 & 1.52 & 1.5 & 2.0 \\  & T1P9 & 19.81 & 37.18 & 8.82 & 0.45 & 31.1 & 1.6 \\ \hline \hline \end{tabular}
\end{table}
Table 3: For every fast-response point of measurement, mean concentration, peak concentration, standard deviation of concentration, intensity of concentration, 90 th percentile concentration and R\({}_{90}\) are reported. The receptors are indicated as TP, where T is the crossbar and P represents the subject which occupies the point where the measurements take place. The numbers indicate which of the two transvers and which of the twelve positions.  
factor of two from the perfect value, have been highlighted. The linear trendline was added, obtaining an angular coefficient of 0.7778 (showing a slight underestimation of the average concentration values by the model), an intercept of 1.066 (exhibiting fairly low bias) and a \(R^{2}\) = 0.6054 (denoting a low dispersion of the data). This agreement between the average concentrations data was considered better than acceptable.