# IoT-Based Solid Waste Management Solutions: A Survey
## 7 Open Issues and Challenges
In the category of software analysis, five models for dynamic programming are considered and the dynamic routing is also present in five models, while real experimental data are adopted just in one model, with all other models using simulators. Among all the papers analyzed, from physical infrastructure, many authors propose a waste management model through IoT with collection emphasis, offering scheduling models with dynamic routing for greater effectiveness of collection, using low fuel consumption. Other authors focus on specific bins for each type of waste that promote to users a selective disposal way; there are even models where a bonus based on the amount of recyclable waste is offered to the user and models where the user, based on a mobile app, can query particular green waste points. There are also authors who propose recycling and processing points not relevant to this research. In a general context, all the models have a focus on the collection system. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Ref.** & **RFID** & **Sensors** & **Actuators** & **Camera** & **GPS** & **Architecture** \\ \hline
[35] & Disregard & Capacity; Weight & Disregard & Disregard & Disregard & Implied \\  & & Capacity; Weight; & & & & \\
[36] & Incorporated & Temperature; Humidity; & Incorporated & Disregard & Incorporated & Defined \\  & & Chemical; Pressure & & & & \\
[37] & Disregard & Capacity & Disregard & Disregard & Disregard & Implied \\
[38] & Disregard & none & Disregard & Disregard & Disregard & Defined \\
[39] & Disregard & Capacity & Disregard & Disregard & Disregard & Implied \\
[40] & Incorporated & Capacity & Disregard & Disregard & Disregard & Defined \\
[41] & Incorporated & Capacity & Disregard & Disregard & Disregard & Defined \\
[42] & Incorporated & Capacity; Weight & Disregard & Disregard & Incorporated & Defined \\
[43] & Disregard & Capacity & Disregard & Disregard & Incorporated & Defined \\
[44] & Disregard & Capacity & Disregard & Disregard & Incorporated & Defined \\
[45] & Disregard & Capacity & Disregard & Disregard & Disregard & Defined \\
[46] & Disregard & Capacity & Disregard & Disregard & Disregard & Defined \\
[47] & Incorporated & Capacity & Disregard & Disregard & Disregard & Defined \\
[48] & Not Specified & Not Specified & Not Specified & Not Specified & Not Specified & Not Specified \\
[49] & Not Specified & Not Specified & Not Specified & Not Specified & Not Specified \\ \hline \hline \end{tabular}
\end{table} 
Table 2: IoT Technology comparison for the most relevant solutions available in the literature (Table 1). \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Ref.** & **Dynamic Scheduling** & **Dynamic Routing** & **Experimental Data** \\ \hline
[35] & Not defined & Not defined & Simulator \\
[36] & Defined & Defined & Simulator \\
[37] & Defined & Defined & Simulator \\
[38] & Not defined & Not defined & Simulator \\
[39] & Defined & Defined & Simulator \\
[40] & Not defined & Not defined & Simulator \\
[41] & Not defined & Not defined & Simulator \\
[42] & Not defined & Not defined & Simulator \\
[43] & Not defined & Not defined & Simulator \\
[44] & Not defined & Not defined & Real \\
[45] & Defined & Defined & Simulator \\
[46] & Defined & Defined & Simulator \\
[47] & Not defined & Not defined & Simulator \\
[48] & Defined & Defined & Simulator \\
[49] & Defined & Defined & Simulator \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Experimental analysis comparison for the most relevant solutions available in the literature (Table 1). Considering aspects of IoT technology, some authors incorporate the identification of a waste bin through RFID and others not, a fact that makes it not necessary when a GPS is considered, but few models adhere to GPS technology. The variety of sensor types is not well explored in most models, which can lead to false positives when waste disposal is low in volume and high in weight. Automatic actuators are not necessary, since not all types of discards are actually compressible.