Improved Characters Feature Extraction and Matching Algorithm Based on SIFT

According to SIFT algorithm does not have the property of affine invariance, and the high complexity of time and space, it is difficult to apply to real-time image processing for batch image sequence, so an improved SIFT feature extraction algorithm was proposed in this paper. Firstly, the MSER algorithm detected the maximally stable extremely regions instead of the DOG operator detected extreme point, increasing the stability of the characteristics, and reducing the number of the feature descriptor; Secondly, the circular feature region is divided into eight fan-shaped sub-region instead of 16 square sub-region of the traditional SIFT, and using Gaussian function weighted gradient information field to construct the new SIFT features descriptor. Compared with traditional SIFT algorithm, The experimental results showed that the algorithm not only has translational invariance, scale invariance and rotational invariance, but also has affine invariance and faster speed that meet the requirements of real-time image processing applications. DOI : http://dx.doi.org/10.11591/telkomnika.v12i1.400

How Does Misperception Affect Zero-Determinant Strategies In Iterated Prisoner’s Dilemma?

Abstract Zero-determinant (ZD) strategies have attracted wide attention in Iterated Prisoner’s Dilemma (IPD) games, since the player equipped with ZD strategies can unilaterally enforce the two players’ expected utilities subjected to a linear relation. On the other hand, uncertainties, which may be caused by misperception, occur in IPD inevitably in practical circumstances. To better understand the situation, we consider the influence of misperception on ZD strategies in IPD, where the two players, player X and player Y , have different cognitions, but player X detects the misperception and it is believed to make ZD strategies by player Y. We provide a necessary and sufficient condition for the ZD strategies in IPD with misperception, where there is also a linear relationship between players’ utilities in player X’s cognition. Then we explore bounds of players’ expected utility deviation from a linear relationship in player X’s cognition with also improving its own utility.</jats:p

Zero-determinant strategy in stochastic Stackelberg asymmetric security game

Abstract In a stochastic Stackelberg asymmetric security game, the strong Stackelberg equilibrium (SSE) strategy is a popular option for the defender to get the highest utility against an attacker with the best response (BR) strategy. However, the attacker may be a boundedly rational player, who adopts a combination of the BR strategy and a fixed stubborn one. In such a condition, the SSE strategy may not maintain the defensive performance due to the stubbornness. In this paper, we focus on how the defender can adopt the unilateral-control zero-determinate (ZD) strategy to confront the boundedly rational attacker. At first, we verify the existence of ZD strategies for the defender. We then investigate the performance of the defender’s ZD strategy against a boundedly rational attacker, with a comparison of the SSE strategy. Specifically, when the attacker’s strategy is close to the BR strategy, the ZD strategy admits a bounded loss for the defender compared with the SSE strategy. Conversely, when the attacker’s strategy is close to the stubborn strategy, the ZD strategy can bring higher defensive performance for the defender than the SSE strategy does

Equalizer Zero-Determinant Strategy in Discounted Repeated Stackelberg Asymmetric Game

This paper focuses on the performance of equalizer zero-determinant (ZD) strategies in discounted repeated Stackelberg asymmetric games. In the leader-follower adversarial scenario, the strong Stackelberg equilibrium (SSE) deriving from the opponents’ best response (BR), is technically the optimal strategy for the leader. However, computing an SSE strategy may be difficult since it needs to solve a mixed-integer program and has exponential complexity in the number of states. To this end, the authors propose an equalizer ZD strategy, which can unilaterally restrict the opponent’s expected utility. The authors first study the existence of an equalizer ZD strategy with one-to-one situations, and analyze an upper bound of its performance with the baseline SSE strategy. Then the authors turn to multi-player models, where there exists one player adopting an equalizer ZD strategy. The authors give bounds of the weighted sum of opponents’s utilities, and compare it with the SSE strategy. Finally, the authors give simulations on unmanned aerial vehicles (UAVs) and the moving target defense (MTD) to verify the effectiveness of the proposed approach.</p

Misperception influence on zero-determinant strategies in iterated Prisoner’s Dilemma

AbstractZero-determinant (ZD) strategies have attracted wide attention in Iterated Prisoner’s Dilemma (IPD) games, since the player equipped with ZD strategies can unilaterally enforce the two players’ expected utilities subjected to a linear relation. On the other hand, uncertainties, which may be caused by misperception, occur in IPD inevitably in practical circumstances. To better understand the situation, we consider the influence of misperception on ZD strategies in IPD, where the two players, player X and player Y, have different cognitions, but player X detects the misperception and it is believed to make ZD strategies by player Y. We provide a necessary and sufficient condition for the ZD strategies in IPD with misperception, where there is also a linear relationship between players’ utilities in player X’s cognition. Then we explore bounds of players’ expected utility deviation from a linear relationship in player X’s cognition with also improving its own utility.</jats:p