It is unfeasible to analyze the security events by the manual way for the security manager, because the number of the events is huge and the information contained in the events is meaningless. After analyzing the exis...
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The constant modulus algorithm (CMA) is one widely used algorithm for blind equalization of QAM signals. The algorithm exhibits slow convergence rate and large steady state mean square error and the phase-blind nature...
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ISBN:
(纸本)9781934142141
The constant modulus algorithm (CMA) is one widely used algorithm for blind equalization of QAM signals. The algorithm exhibits slow convergence rate and large steady state mean square error and the phase-blind nature in comparison with the algorithms used in conventional data-aided equalization schemes. In this paper, a variable step size modified constant modulus algorithm is proposed. The proposed algorithm can speed up convergence rate and decrease steady state mean square error and correct phase error and frequency offset at the same time. The simulation results demonstrate the effectiveness of the proposed algorithm in improving convergence rate and reducing steady state mean square error.
A modeling and verification methodology is presented for railway interlocking system which is regarded as a safety-critical system. The methodology utilizes UML (Unified Modeling Language) to model the function requir...
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ISBN:
(纸本)9781424472369
A modeling and verification methodology is presented for railway interlocking system which is regarded as a safety-critical system. The methodology utilizes UML (Unified Modeling Language) to model the function requirement and FSM (Finite State Machine) to verity the safety requirements of the specification. The device specifications of railway interlocking system are modeled with UML, and dynamic behaviors of the device and whole system are modeled with FSM, the safety specification is translated LTL (Linear Temporal Logic) and analyzed with NuSMV. We try to show the feasibility of improving the reliability and reducing revalidation efforts when designing and developing a decentralized railway signaling system.
Evolutionary games are widely studied in the fields of biology, sociology, economics and informatics. People's interests focus on how cooperation emerged in a system that individuals are selfish. We studied the it...
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ISBN:
(纸本)9787894631046
Evolutionary games are widely studied in the fields of biology, sociology, economics and informatics. People's interests focus on how cooperation emerged in a system that individuals are selfish. We studied the iterated Prisoner's Dilemma Game evolved on BA network with genetic algorithm. Nodes in network could remember the game historical strategies and coded into gene. We show that memory length has gentle effect on cooperation level, and that some characteristic genes and frequentlyused genes emerge after some generations. We also find that cooperate strategy distributed on different degree-nodes equably. These findings give new perspectives to the illustration of cooperation behavior in biological group and society.
It is unfeasible to analyze the security events by the manual way for the security manager, because the number of the events is huge and the information contained in the events is meaningless. After analyzing the exis...
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It is unfeasible to analyze the security events by the manual way for the security manager, because the number of the events is huge and the information contained in the events is meaningless. After analyzing the existing algorithms of security events correlation, we propose an attack scenario reconstruction technology based on state machine. The processes of attackers intruding into the cyberspace can be restored and the more comprehensive attack scenario description information will be generated using this technology. This working lets the security manager more comfy. The state machine based attack scenario reconstruction technology processes security events using clustering analysis and causal analysis concurrently, it builds a correlation state machine in memory for every attack scenario tree which is predefined by the security manager, when security events are coming, the certain state machines will process them, if the condition is satisfied, an attack scenario description information will be generated and then sent to the security manager. The correlating technology based on state machine is more timely and accurately, and at last, we use the DARPA2000 Intrusion Scenario Specific Data Sets to validate the technology, the experiment results show that it is feasible to analyze security events using the technology we proposed.
The constant modulus algorithm (CMA) is one widely used algorithm for blind equalization of quadrature amplitude modulation (QAM) signals. The algorithm exhibits slow convergence rate and large steady state mean squar...
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The constant modulus algorithm (CMA) is one widely used algorithm for blind equalization of quadrature amplitude modulation (QAM) signals. The algorithm exhibits slow convergence rate and large steady state mean square error and the phase blind nature in comparison with the algorithms used in conventional data-aided equalization schemes. In this paper, a variable step size modified constant modulus algorithm is proposed. The proposed algorithm can achieve fast convergence rate and decrease steady state mean square error and correct phase shift and carrier frequency offset at the same time. The simulation results demonstrate the effectiveness of the proposed algorithm in improving convergence behavior and bit error rate performance.
There many researches about modulation mode classification of the MPSK signals, but these studies pay few attentions to some especial MPSK signals such as OQPSK or π/4QPSK. However, the signals are very important in ...
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There many researches about modulation mode classification of the MPSK signals, but these studies pay few attentions to some especial MPSK signals such as OQPSK or π/4QPSK. However, the signals are very important in the digital communications. The method of classification of the QPSK, OQPSK, π/4QPSK and 8PSK has discussed in this paper, because these MPSK signals have similar constellations or spectrum. The method of the classification and parameter estimation based on the statistical and spectral characters of the instantaneous phase difference (IPD) is proposed. The simulation results of the digital signals indicate that this method is availability when the SNR is higher than 5dB.
This paper aims to model and solve the Sum and Product Riddle in public announcement logic. A dynamic epistemic model is proposed, that is the linear temporal combination of the epistemic model of environment and the ...
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This paper aims to model and solve the Sum and Product Riddle in public announcement logic. A dynamic epistemic model is proposed, that is the linear temporal combination of the epistemic model of environment and the epistemic models after each announcement, such that the authors' model checking technique for temporal epistemic logic can be extended to support the modeling and verification of public announcement logic. This model checking method not only can help to find all solutions, but also verify related temporal epistemic properties. Such characteristic is not fully supported by the current version of MCK, MCMAS and DEMO. The authors implemented the proposed method in the symbolic model checker MCTK via OBDD and verified the sum and product riddle. The experimental results show that the proposed method is correct and efficient.
To improve matching ratio and decrease computational complexity of graph/hypergraph matching, an image registration algorithm based on sparse position hypergraph matching is proposed in this paper. Firstly, the graph ...
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To improve matching ratio and decrease computational complexity of graph/hypergraph matching, an image registration algorithm based on sparse position hypergraph matching is proposed in this paper. Firstly, the graph model is constructed through extracting features from real images. Secondly, after getting the minimum spanning tree structure which contains the main connections among nodes of graph, sparse position hypergraph is obtained by using the position angle information of hyper-edge composed of three neighboring nodes in the minimum spanning tree. Thirdly, a inter-graph point proximity matrix is built by the position angle information. At last, an approach of global optimal soft matching is used to achieve matching. It can be clearly indicated that this algorithm has low computational complexity and is robust for image matching.
The carrier recovery is one key technique in the demodulation of high order quadrature amplitude modulation (QAM) signals. A carrier recovery algorithm which switches between multi-threshold polarity decision mode and...
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The carrier recovery is one key technique in the demodulation of high order quadrature amplitude modulation (QAM) signals. A carrier recovery algorithm which switches between multi-threshold polarity decision mode and decision directed mode according to the standard deviation of the frequency of numerically controlled oscillator (NCO) is proposed. The proposed algorithm can detect a proper time for the mode switch to yield lower steady state error. The simulation results demonstrate the effectiveness of the proposed algorithm in improving the performance of blind carrier recovery.
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