# Design and Implementation of a Smart Traffic Signal Control System for Smart City Applications
## 2 Related Works on ITS Applications
### V2X-Based Eco-Driving  
[PERSON] et al. proposed two eco-driving models, the maximum throughput model (MaxTM) and the minimum acceleration and deceleration model (MinADM) [22]. This work shows that the performance of carbon emissions is 5-102% better than MinADM and 13-209% better than the compared baseline (OTLCM [23]). In real traffic cases, MaxTM is 8-14% better than MinADM and 15-231% better than OTLCM. [PERSON] and [PERSON] extended eco-driving models in [22] from standalone intersection to multiple intersections, an energy-saving driving advisory system (EDAS) was introduced [24]. OBU calculates the speed range for passing through at most four intersections based on signal plans broadcasted by RSU. Two strategies including the maximum throughput model (MTM) and smooth speed model (SSM) are designed and being adopted according to the degree of traffic congestion. Experimental results show that the MTM of the single intersection travel time is 20.5-84.3% less than the OTLCM. The carbon emissions of continuous intersections MTM+SSM are 19.9-31.2% less than predictive cruise control (PCC) model [25], and MTM+SSM is 24.5-35.9% less than PCC in travel time. The discussions of literature related to eco-driving models including concepts, relationship between RSU and OBU, benefits, and applications are summarized as in Table 2. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**ATSC Model** & **Sensor** & **Sensor Location** & **Control Strategy** \\ \hline
**SCOOT [16]** & Loop & Upstream 10–20 m &
\begin{tabular}{c} Minimize the sum of the \\ averaged queue \\ \end{tabular} \\ \hline
**SCAT [17]** & Loop & Stop line & Minimize stops and travel time \\ \hline
**RHODES [18]** & Loop & Upstream of the stop line &
\begin{tabular}{c} OD matrix, flow control, \\ and signal control \\ \end{tabular} \\ \hline
**COMPYCS III [19]** & Loop &
\begin{tabular}{c} Two detectors: 0 m and \\ 150–300 m from stop line \\ \end{tabular} & Multiple optimization objectives \\ \hline
**LIOVRA [20]** & Loop &
\begin{tabular}{c} 10 m, 85 m, 140 m, 200 m, \\ 300 m from stop line \\ \end{tabular} & Multiple optimization objectives \\ \hline
**OPAC [21]** & Loop & upstream 400–600 feet &
\begin{tabular}{c} Maximize the sum of performance \\ indices on all approaches \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Adaptive traffic signal control models. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Eco-Driving** & \multirow{2}{*}{**Concept**} & \multirow{2}{*}{**Actions**} & \multirow{2}{*}{**Benefit**} & **Application** \\
**Model** & & & & \\ \hline
**MaxTM,** & \begin{tabular}{c} Max. throughput \\ and Min. \\ acceleration and \\ deceleration \\ \end{tabular} & \begin{tabular}{c} OBU suggests \\ eco-driving speed \\ \end{tabular} & \
\begin{tabular}{c} Reduce carbon \\ emissions, fuel \\ consumption, \\ travel time \\ \end{tabular} &
\begin{tabular}{c} Standalone \\ intersection \\ \end{tabular} \\ \hline
**VANET–based** & \multirow{2}{*}{\begin{tabular}{c} Forecasting and \\ decision making \\ \end{tabular} } & \begin{tabular}{c} RSU determines \\ traffic signal plan \\ \end{tabular} & \
\begin{tabular}{c} Reduce carbon \\ emissions and fuel \\ consumption \\ \end{tabular} &
\begin{tabular}{c} Multiple \\ intersections \\ \end{tabular} \\ \hline
**EDAS System [24]** & \begin{tabular}{c} Calculate the \\ number of \\ intersections that \\ can be passed and \\ take different \\ modes \\ \end{tabular} & \begin{tabular}{c} OBU suggests \\ eco-driving speed \\ \end{tabular} & \
\begin{tabular}{c} Reduce carbon \\ emissions, fuel \\ consumption, \\ travel time \\ \end{tabular} &
\begin{tabular}{c} Multiple \\ intersections \\ \end{tabular} \\ \hline
**TTE& \begin{tabular}{c} Travel time \\ prediction and path \\ recommendations \\ \end{tabular} & \
\begin{tabular}{c} OBU forecasts \\ travel time and \\ suggests path \\ \end{tabular} &
\begin{tabular}{c} Reduce \\ computational \\ complexity and \\ reduce travel time \\ \end{tabular} & Multiple \\ \hline \hline \end{tabular}
\end{table}