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12                                                                UEC Int’l Mini-Conference No.52







                                      Table 1: State set for the proposed algorithm.

                                               State      Link Order
                                                S1    q1 ≥ q2 ≥ q3 ≥ q4
                                                S2    q1 ≥ q2 ≥ q4 ≥ q3
                                                S3    q1 ≥ q3 ≥ q2 ≥ q4
                                                S4    q1 ≥ q4 ≥ q2 ≥ q3
                                                S5    q1 ≥ q3 ≥ q4 ≥ q2
                                                S6    q1 ≥ q4 ≥ q3 ≥ q2
                                                S7    q2 ≥ q1 ≥ q3 ≥ q4
                                                S8    q2 ≥ q1 ≥ q4 ≥ q3
                                                S9    q3 ≥ q1 ≥ q2 ≥ q4
                                                S10   q4 ≥ q1 ≥ q2 ≥ q3
                                                S11   q3 ≥ q1 ≥ q4 ≥ q2
                                                S12   q4 ≥ q1 ≥ q3 ≥ q2
                                                S13   q2 ≥ q3 ≥ q1 ≥ q4
                                                S14   q2 ≥ q4 ≥ q1 ≥ q3
                                                S15   q3 ≥ q2 ≥ q1 ≥ q4
                                                S16   q4 ≥ q2 ≥ q1 ≥ q3
                                                S17   q3 ≥ q4 ≥ q1 ≥ q2
                                                S18   q4 ≥ q3 ≥ q1 ≥ q2
                                                S19   q2 ≥ q3 ≥ q4 ≥ q1
                                                S20   q2 ≥ q4 ≥ q3 ≥ q1
                                                S21   q3 ≥ q2 ≥ q4 ≥ q1
                                                S22   q4 ≥ q2 ≥ q3 ≥ q1
                                                S23   q3 ≥ q4 ≥ q2 ≥ q1
                                                S24   q4 ≥ q3 ≥ q2 ≥ q1


            2.2   Action Representation                       prove safety. It integrates data from loop detec-
                                                              tors and CAVs to improve accuracy. The queue
            Actions in the proposed algorithm involve ad-     length detected by both methods is used to cal-
            justing signal timings based on current traffic   culate the reward, which adjusts the weight of
            conditions. Two primary actions can be chosen:    the two methods through MPR.
            extending the green time by 1 second or not ex-     The reward function R(s, a) is defined as fol-
            tending it. These actions allow the algorithm to
                                                              lows:
            dynamically respond to real-time traffic condi-
                                                                         R(s, a) = (1 − ϵ)q + ϵq ′     (1)
            tions and optimize traffic flow.
              The action space is represented as follows:     where:

              • Extend Green Time: Increase the green           • q is the queue length estimated by loop de-
                signal duration for the current phase by 1        tectors.
                second.
                                                                   ′
                                                                • q is the queue length detected by CAVs.
              • Do Not Extend Green Time: Maintain              • ϵ is the current Market Penetration Rate
                the current green signal duration.                (MPR) of CAVs.


                                                                This weighted approach allows the algorithm
            2.3   Reward Function
                                                              to balance the accuracy of data from different
            The reward function is designed to encourage      sources and make informed decisions that opti-
            actions that reduce traffic congestion and im-    mize traffic flow and safety.
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