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Th is paper presents a new random mu ltiple access control protocol - 1-persistent CSMA control protocol based on improved binary tree conflict resolution algorithm. First, the paper gives an outline of 1-persistent CSMA and the binary tree conflict-resolving algorith m by build ing a mathematical model and using the average cycle method, and then respectively obtains the throughput and the number of time -slots of the protocol and the algorith m. The simulation results are g iven, and agree well with theoretical values. But, in a shared channel, each user independently sends information packets randomly, and it is prone to conflict and resulting in the failure. Especially to the 1-persistent CSMA control protocol, when the load is larger, it has a lower throughput and greatly increasing the probability of channel conflict. Therefore, bringing in the binary tree conflict-resolving algorith m is a good method to imp rove the throughput, especially the improved binary tree conflict resolution algorith m. So at last, the paper introduces the random mu ltip le access protocol comb ined improved binary tree conflict resolution algorith m and 1-persistent CSMA protocol, obtains the throughput and gives the simulations of the joint protocol. Theoretical calculations and experimental results show that 1-persistent CSMA protocol with conflict-resolving has a better performance.

This paper puts forward a joint control protocol based on binary tree conflict-resolving algorithm combined probability detection and 1-persistent CSMA. Under the protocol, all terminals use the joint control protocol of p-detection and 1-persistent to access the channel before sending information packets, and transmit packets immediately when the channel is idle, but when there are any collisions on the channel, the system will use isolated binary tree conflict-resolving technology to decompose the impacted packets. Meanwhile, the paper analyzes the protocol and gets the computational formula of the throughput for the protocol by building a mathematical model and using the average cycle method and compared with the joint control protocol of p-detection and 1-persistent. And finally, the paper gives the MATLAB simulation results. The results not only show that the correctness of the theoretical analysis and illustrates the validity of the protocol, but also gives some meaningful conclusions. Therefore, it is very necessary and important to integrate the binary tree conflict-resolving technology into the joint control protocol of p-detection and 1-persistent under high load, which can the successful probability and channel utilization.

This paper proposed a new type of discrete random contention system based on the literature (1), researched it using the average cycle method, then get the formu la of the systemic throughput for the new random access protocol by building mathematical modeling; but the uncertainty of random mult iple access on frequency and time resulting in the conflict probability increases as the higher loading, therefore, introducing binary tree conflict resolution algorithm is very important to improve the channel utilizat ion. The paper analyzed the isolated binary tree conflict resolution algorithm and then got the average length of t imeslot of the algorithm; on the basis, the paper puts forward a new type of discrete random contention system based on binary tree conflict resolution algorith m. Analytic formulate for throughput of the new d iscrete random contention system and the system based on the conflict resolution algorith m are derived by build ing mathematical model and using the average cycle method. Finally, the computer simu lation experiments show that the correctness of the theoretical, at the same t ime, show that the new discrete random contention system protocol based on binary tree conflict resolution algorithm is effective to further improve the system performance.

Some life tests result in few or no failures. In such cases, we can, and should, consider using degradation measurements to assess reliability. In real world, product degradation is a stochastic process. Since such degradation is often seen as a monotonous process, literature widely uses Gamma Process to describe and quantify degradation. However, in these publications, scale parameter is considered constant over time and results under this assumption may have big deviation from the actual measurements under nonlinear condition. The purpose of this paper is to improve Gamma Process method to fit a broader class of degradation models. Firstly, we use MLE to estimate the parameters under the timely constant-scale-parameter assumption and analyze why the model does not fit data well. Then we propose an improved model to improve the method and use Monte Carlo simulation to verify the validity of the improved method.

The technology of strengthening RC structures with grouting material is a new type of reinforcement techniques in the field of construction reinforcement in recent years. Considering the reduction of the strength and stiffness of flexural members in RC structures due to steel corrosion, this paper simulated steel corrosion artificially and then reinforced with grouting material to study the grouting material reinforcement effect of corroded RC flexural members. Based on the test of 3 beams and 2 slabs, failure characteristics and their effects on the ultimate bearing capacity and stiffness of corroded RC flexural members strengthened with grouting material were researched and analyzed. The result shows that grouting material reinforcement can observably improve RC bending members' flexural behavior and supporting capacity, meanwhile enlarge structural stiffness to put off the appearance of cracks and inhibit the expansion and extension of cracks. The research results are of great value in the practical design.

A solution is urgently expected to meet the higher-quality web service requirements of multimedia applications on the limited bandwidth of internet. Based on the ideas of priority-based service and dynamic load adaptation, this paper presents a new scheduling algorithm for multimedia support in web cluster servers , making possible the service of the two-class priority station polling system under the mixed policy of exhaustive and gated services, optimizing the services of the system in time of load change input via adjustment of the times of the access gated services, and strengthening the flexibility and fairness of multimedia transmissions in web service system. The theoretical model of this algorithm is established with Markov chain and probability generating function. Mathematical analysis is made on the mean queue length and the mean inquiry cyclic time of the common queue and the key station. It turns out that the findings from theoretical analysis correspond well with those from simulated experiments.

In the Internet of Things, the remote monitoring, network status tracking, fault alarm, automatic measurement and control functions of the random access system require the system has the function of the receiver to send client feedback monitoring information. For the network status monitoring requirements in the Internet of Things, this article proposes a monitoring function for random access system, and we get to the throughput, idle rate and information packet collision rate of the system with the average cycle analysis method, through computer simulations to verify the correctness of the analysis.

A solution is urgently expected to meet the higher-quality web service requirements of various applications on the limited bandwidth of internet. This paper presents a new scheme of load balance of web cluster servers, making possible the service of the two-class priority station polling system under the mixed policy of exhaustive and gated services, optimizing the services of the system in time of load change input via adjustment of the times of the access gated services, and strengthening the flexibility and fairness of multimedia transmissions in web cluster system. The theoretical model of this scheme is established with Markov chain and probability generating function. Mathematical analysis is made on the mean queue length and the mean inquiry cyclic time of the common queue and the key station. It turns out that the findings from theoretical analysis correspond well with those from simulated experiments.

With the development of wireless network, a solution is urgently expected to meet the higher-quality QoS demands of multimedia traffics especially when the network is heavily loaded. This paper presents a new scheme of MAC protocol of wireless network, optimizing the services of the system in time of load change input via adjustment of the times of the access gated services. The scheme does not modify the current protocol infrastructure or add any overheads. The theoretical model is established with Markov chain and probability generating function. Mathematical analysis is made on the mean queue length and the mean cyclic time of the common queue and the key station. It turns out that the findings from theoretical analysis correspond well with those from simulated experiments and strengthen the flexibility and fairness of multimedia transmissions in wireless system.

This paper proposed a novel analytical model of the polling MAC protocol using M-gated services in continuous time. By the imbedded Markov chain theory, the generating functions of queue length at server arrival epoch is obtained. Also, the Laplace-Stieltjes transform (LST) of packet delay distribution function is derived. Then computational equations are explicitl determined for the mean queue length and the mean packet delay. Through analysis of the mechanism of the polling model, its control values of the M-gated service and the related properties have been obtained. Meanwhile, the basic polling systems using gated service and exhaustive service have been improved. The polling MAC control protocol in the application is more effective.

In this paper we consider the polling system with multiple vacations using exhaustive service. By the imbedded Markov chain theory, the generating functions of queue length at the station is obtained. Then computational equations are explicitly determined for the mean queue length and the mean waiting time of information packet. Especially we obtain some corresponding results under some especial cases. The results are verified through extensive simulations.

Many wireless sensor networks (WSN) application systems are composed of multiple sensor nodes serial processing system. This paper sets up the model for the serial processing system using gated service in wireless sensor networks, and studies it by the Markov chain theory and the probability generating function method, the calculating equation of the mean waiting time of message packet is obtained by every sensor node in the serial processing system. We obtain corresponding results under some especial cases. Finally, the simulation results are given.

To discover firing case in time, the technique of wireless sensor networks is applied to fire early system. This paper establishes the early warning system applied to fire prevention model of serial transmission mode with vacation using exhaustive service for wireless sensor networks. We derive the calculating equation of information packet delay for each sensor node in the system by the Markov chain theory and the probability generating function method. Finally, the theoretical analysis results are confirmed through using simulation.