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This paper presents an approach and analysis for performing decentralized cooperative control of a team of decoys to achieve the Honeypot Ambush tactic. In this tactic, the threats are successfully lured into a designated region where they can be easily defeated. The decoys learn to cooperate by incorporating a game-theory-based online-learning method, known as regret minimization, to maximize the team's global reward. The decoy agents are assumed to have physical limitations and to be subject to certain stringent range constraints required for deceiving the networked threats. By employing an efficient coordination mechanism, the agents learn to be less greedy and allow weaker agents to catch up on their rewards to improve team performance. Such a coordination solution corresponds to achieving convergence to coarse correlated equilibrium. The numerical results verify the effectiveness of the proposed solution to achieve a global satisfaction outcome and to adapt to a wide spectrum of scenarios.

This paper studies the coordination issue of a supply chain consisting of one retailer and two suppliers, a main supplier and a backup supplier. The main supplier’s yield is subject to disruption and the retailer faces a random demand. We determine the retailer’s optimal ordering policy and the main supplier’s production quantity that maximize expected profit of the centralized supply chain. We also analyze the decentralized scenario, and a combination of overproduction risk sharing and buy-back contracts with a side payment from/to the backup supplier is provided to coordinate the supply chain. Numerical examples are given to gain some qualitative insights.

This paper addresses the problems of the input-to-state stochastic stability for neutral switched stochastic delay systems. Two switching signals in the input controller, including the external input disturbance, are considered: (1) the synchronous switching signal, which indicates that the switching signal of the input controller coincides with that of the controlled subsystems, and (2) the asynchronous switching signal, which signifies that two switching instants for the input controller and the subsystem are not identical. Irrespective of which switching signal exists in the input controller and the subsystem, multiple Lyapunov--Krasovskii functions, generalized delay integral inequality, and mode-dependent average dwell time are incorporated to analyze the underlying problem. Sufficient conditions based on two integral inequalities are obtained for these two cases, respectively. Also new and more relaxed Lyapunov monotonicity conditions are introduced. One simulation example is provided to demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

This paper explores the design problem of consensus algorithms in a class of convex geometric metric spaces. Using the techniques of convex analysis and possibility analysis, a simple assumption for designing consensus algorithms in a strict max-convex space is proposed, under which all dynamical points in a system achieve consensus asymptotically if and only if their associated interaction graph uniformly contains at least one directed spanning tree. Three efficient consensus algorithms under the assumption are presented, and their applications are demonstrated together with efficiency studies. [ABSTRACT FROM AUTHOR]

This paper establishes new criteria for stochastic suppression and stabilization of hybrid functional differential systemswith general 1-sided polynomial growth condition. For an unstable nonlinear hybrid functional differential system with general 1-sided polynomial growth condition, 2 independent Brownian noise processes are used to perturb the system into the stochastic hybrid differential system. Theoretical analysis shows that one of the nonlinear diffusion termsmay suppress the explosive solution of deterministic system, and the other one can make the perturbed hybrid system almost surely stable with general decay rate. [ABSTRACT FROM AUTHOR]

A new model reduction (MR) method is developed for continuous-time switched linear parameter-varying (LPV) systems based on time-weighted gramians. Using time-weighted energy functionals and parameter-independent multiple Lyapunov functions, the time-weighted controllability and observability gramians are obtained. With a balanced transformation matrix optimally derived, the authors show that a balanced realisation can be achieved for the original switched LPV systems. A series of low-order models for different weighting factors are yielded by state truncation or singular perturbation techniques. The reduced-order models can preserve the stability. The feasibility and effectiveness of the proposed MR method are illustrated by two examples including a three spring-mass system. [ABSTRACT FROM AUTHOR]

Triple I method was proven to be the effective reasoning method with solid logic foundation, however, the existing works about triple I method all neglect inconsistent bipolarity information in reasoning process, which exists in the way that our brain handles information. Considering that bipolar-valued fuzzy set theory is a powerful tool to describe inconsistent fuzzy bipolarity information, this paper introduces inconsistent bipolarity to triple I method for the first time, and systematically studies the triple I fuzzy modus tollens method with inconsistent bipolarity information based on the regular implication. First, some new concepts about inconsistent fuzzy bipolarity information are introduced. And by introducing the concept of YinYang bipolar-valued induced function, we can induce bipolar-valued operations under the YinYang order relation from the corresponding unipolar ones. Then the triple I bipolar-valued fuzzy modus tollens methods under the YinYang order relation are proposed, together with the solutions. It is proved that the solutions can degenerate into two corresponding unipolar triple I fuzzy modus tollens solutions. Lastly, reductive property, approximation property and robustness of the proposed methods are discussed. [ABSTRACT FROM AUTHOR]

In order to improve the utilization efficiency of resources, more and more countries have required manufacturing firms to remanufacture or reuse used products through legislation. For many firms, the profit from reusing used products may be less than the profit from producing new products, so how to make decisions under such legislation constraint is a major concern by these firms. In this paper, we study the optimal acquisition, inventory and production decision problem for such firms under a two-period setting, where firms have two different production ways: (i) production with new raw materials, and (ii) production with used products. The return quantity of used products at the second period depends on the demand of the first period and the acquisition effort. The problem is formulated as a stochastic dynamic programming model. We give the optimal production rule and the optimal inventory decision at the second period, and prove the existence of an optimal policy with a simple structure at the first period. Moreover, based on our theoretical analysis, we calculate the optimal decisions under different parameter settings, and discuss how the firm does react when facing with specific market and production conditions. [ABSTRACT FROM AUTHOR]

The problem of H∞ fault-tolerant control for networked control systems (NCSs) with actuator failures is addressed in this study. The authors consider the network induced delays, including sensor to controller delay and controller-to-actuator delay, to have both an upper bound and a non-zero lower bound. By using a sampled-data approach, a new model is formulated based on the updating instants of the ZOH. They derive the criteria which ensure that the sample-data NCS is stable with H∞ norm γ . The authors design the H∞ fault-tolerant controller that guarantees the closed-loop NCS stability with H∞ norm γ , when all control components are operational, as well as when some actuators fail to operate. Simulation examples are given to show the effectiveness and less conservative needs of the proposed method. [ABSTRACT FROM AUTHOR]

Verification of semiconductor chip designs is commonly driven by single goal orientated measures. With increasing design complexities, this approach is no longer effective. We enhance the effectiveness of coverage driven design verifications by applying multi-objective optimization techniques. The technique is based on genetic evolutionary algorithms. Difficulties with conflicting test objectives and selection of tests to achieve multiple verification goals in the genetic evolutionary framework are also addressed. [ABSTRACT FROM AUTHOR]

This work addresses the problem of tracking mobile robots in indoor wireless sensor networks (WSNs).Our approach is based on a localization scheme with RSSI (received signal strength indication) which is used widely in WSN. The developed tracking system is designed for continuous estimation of the robot's trajectory. AWSN, which is composed of many very simple and cheap wireless sensor nodes, is deployed at a specific region of interest. The wireless sensor nodes collect RSSI information sent by mobile robots. A range-based data fusion scheme is used to estimate the robot's trajectory. Moreover, a Kalman filter is designed to improve tracking accuracy. Experiments are provided to assess the performance of the proposed scheme. [ABSTRACT FROM AUTHOR]

This paper considers the sliding mode control problem for a kind of dynamic delay system. First by utilizing Lyapunov stability theory and a linear matrix inequality technique, an observer based on delayed output feedback is constructed. Then, an integral sliding surface is presented to realize the sliding mode control for the system with the more available stability condition. Finally, some numerical simulations are implemented to demonstrate the validity of the proposed control method. [ABSTRACT FROM AUTHOR]

For blind channel identification, various techniques, including transmitter-induced cyclostationarity based approaches, have been proposed in literature. To induce cyclostationarity at the transmitter, zero padding to every symbol packet can be considered. Some subspace methods are proposed for the channel estimation by exploiting the induced cyclostationarity. Due to zero padding, the covariance matrix of received signal vectors can have a special structure. Utilizing this structure, we can estimate channel impulse responses through factorization. In this correspondence, we propose a factorization based approach to estimate channel impulse responses. In general, the proposed factorization based approach can work with a small number of samples and becomes much more computationally efficient than the subspace method when the length of packets is long. [ABSTRACT FROM AUTHOR]

A new implementation for minimally redundant radix-4 SRT division with the recurrence in the signed-digit format is introduced. The implementation is developed based on the comparison multiples idea. In the proposed approach, the quotient digit's magnitude is calculated by comparing the truncated partial remainder with two limited precision multiples of the divisor. The sign is determined by investigating the polarity of the truncated partial remainder. A timing evaluation using logical synthesis shows a latency of 2.34 ns for the recurrence of the proposed divider. It is ∼22% less than the conventional implementation. [ABSTRACT FROM AUTHOR]

A new implementation for decimal floating-point (DFP) division is introduced. The algorithm is based on high-radix SRT division with the recurrence in a new decimal signed-digit format. Quotient digits are selected using comparison multiples, where the magnitude of the quotient digit is calculated by comparing the truncated partial remainder with limited precision multiples of the divisor. The sign is determined concurrently by investigating the polarity of the truncated partial remainder. A timing evaluation using a logic synthesis shows a significant decrease in the division execution time in contrast with one of the fastest DFP dividers reported in the open literature. [ABSTRACT FROM AUTHOR]

We present a hand and face segmentation methodology using color and motion cues for the content-based representation of sign language video sequences. The methodology consists of three stages, namely skin-color segmentation, change detection, and face and hand segmentation mask generation. In skin-color segmentations a universal color-model is derived and image pixels are classified as skin or nonskin based on their Mahalanobis distance. We derive a segmentation threshold for the classifier. The aim of change detection is to localize moving objects in a video sequences. The change detection technique is based on the F test and block-based motion estimation. Finally, the results from skin-color segmentation and change detection are analyzed to segment the face and hands. The performance of the algorithm is illustrated by simulations carried out on standard test sequences. [ABSTRACT FROM AUTHOR]

For the code division multiple access (CDMA) downlink channel, we investigate the decision feedback equalizer (DFE) at chip-level to effectively suppress multiple-access interference (MAI) when the spreading sequences are orthogonal. The structure of the receiver with the chip-level DFE has been investigated and the minimum mean-square error solution has been derived. Due to the inherent structure of the chip-level DFE, some iterative techniques with hard and soft decisions have been proposed. It is shown that the proposed receivers with the chip-level DFE can provide satisfactory performance. In comparison with the adaptive chip-level linear equalizer, the number of users can be doubled by using adaptive chip-level DFE at a bit-error rate of 10-3. Throughout the paper, we assume that scrambled orthogonal codes are used for spreading sequences. [ABSTRACT FROM PUBLISHER]