Hidden Maxkov models （HMMs） have been used to model burst error sources of wireless channels. This paper proposes a hybrid method of using genetic algorithm （GA） and simulated annealing （SA） to train HMM for dis...Hidden Maxkov models （HMMs） have been used to model burst error sources of wireless channels. This paper proposes a hybrid method of using genetic algorithm （GA） and simulated annealing （SA） to train HMM for discrete channel modelling. The proposed method is compared with pure GA, and experimental results show that the HMMs trained by the hybrid method can better describe the error sequences due to SA＇s ability of facilitating hill-climbing at the later stage of the search. The burst error statistics of the HMMs trained by the proposed method and the corresponding error sequences are also presented to validate the proposed method.展开更多
The paper provides an overview of geometric solutions of marking all types of serpentine by the method of internal circular curve in designing forest roads directly in the field. The main objective of presenting this ...The paper provides an overview of geometric solutions of marking all types of serpentine by the method of internal circular curve in designing forest roads directly in the field. The main objective of presenting this original method for marking all serpentine types in one place is to show similarities and differences in marking different types of serpentine, and identify opportunities for further research of this type. The method is based on the establishment of the minimum number of elements necessary to mark the serpentine on the forest roads and other budget elements and their design in the field. By using this method, construction errors or the number of attempts of serpentine marking are reduced, which increases the effects of design compared to the ones reached by the previous method of marking the serpentine on forest roads.展开更多
In this paper, a new three-dimensional Markov model is proposed for the estimation of saturation throughput of RTS/CTS (request to send/clear to send) scheme in an error-prone wireless local area network (WLAN) channe...In this paper, a new three-dimensional Markov model is proposed for the estimation of saturation throughput of RTS/CTS (request to send/clear to send) scheme in an error-prone wireless local area network (WLAN) channel. The model takes account of the effect of bit error on all the frames, and station short and long retry limits. Saturation throughput was re-analyzed using the new Markov model and numerical results closely matched those from simulation, confirming the accuracy of the new model. Evaluation of the influence of different parameters on throughput showed that the saturation throughput is sensitive to channel bit error rates and packet length, especially in high bit error conditions.展开更多
Three kinds of quantum relay communication models are proposed,i.e.,the quantum single relay model,quantum serial multi-relay model and quantum parallel multi-relay model.The channel capacities of those three kinds of...Three kinds of quantum relay communication models are proposed,i.e.,the quantum single relay model,quantum serial multi-relay model and quantum parallel multi-relay model.The channel capacities of those three kinds of systems are analyzed with the theory of quantum Markov trace-preserving process and the generalized theory of simple multi-hop channel in quantum system.Motivated by the quantum Fano inequality,the lower bounds of that channel capacities are derived.The illustration and simulation present the trends of the lower bounds on the channel capacities of different quantum relay systems based on the depolarizing noisy channel.展开更多
文摘Hidden Maxkov models （HMMs） have been used to model burst error sources of wireless channels. This paper proposes a hybrid method of using genetic algorithm （GA） and simulated annealing （SA） to train HMM for discrete channel modelling. The proposed method is compared with pure GA, and experimental results show that the HMMs trained by the hybrid method can better describe the error sequences due to SA＇s ability of facilitating hill-climbing at the later stage of the search. The burst error statistics of the HMMs trained by the proposed method and the corresponding error sequences are also presented to validate the proposed method.
文摘The paper provides an overview of geometric solutions of marking all types of serpentine by the method of internal circular curve in designing forest roads directly in the field. The main objective of presenting this original method for marking all serpentine types in one place is to show similarities and differences in marking different types of serpentine, and identify opportunities for further research of this type. The method is based on the establishment of the minimum number of elements necessary to mark the serpentine on the forest roads and other budget elements and their design in the field. By using this method, construction errors or the number of attempts of serpentine marking are reduced, which increases the effects of design compared to the ones reached by the previous method of marking the serpentine on forest roads.
文摘In this paper, a new three-dimensional Markov model is proposed for the estimation of saturation throughput of RTS/CTS (request to send/clear to send) scheme in an error-prone wireless local area network (WLAN) channel. The model takes account of the effect of bit error on all the frames, and station short and long retry limits. Saturation throughput was re-analyzed using the new Markov model and numerical results closely matched those from simulation, confirming the accuracy of the new model. Evaluation of the influence of different parameters on throughput showed that the saturation throughput is sensitive to channel bit error rates and packet length, especially in high bit error conditions.
基金Supported by the National Natural Science Foundation of China under Grant No.60902044the Program for New Century Excellent Talents in University of Ministry of Education of China(NCET-11-0510)+5 种基金the Hunan Provincial Innovation Foundation For Postgraduate under Grant No.CX2011B087the State Scholarship Fund organized by the China Scholarship Council under Grant No.2011637096Excellent Doctoral Dissertation Fund of Central South University under Grant No.2011ybjz030WCU R32-2010-000-20014-0(Korea)FR 2010-0020942(Korea)MEST 2012-002521(NRF Korea)
文摘Three kinds of quantum relay communication models are proposed,i.e.,the quantum single relay model,quantum serial multi-relay model and quantum parallel multi-relay model.The channel capacities of those three kinds of systems are analyzed with the theory of quantum Markov trace-preserving process and the generalized theory of simple multi-hop channel in quantum system.Motivated by the quantum Fano inequality,the lower bounds of that channel capacities are derived.The illustration and simulation present the trends of the lower bounds on the channel capacities of different quantum relay systems based on the depolarizing noisy channel.
