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Leach (low energy adaptive clustering hierarchy) algorithm is a self-clustering topology algorithm. Its execution process is cyclical. Each cycle is divided into two phases: cluster building phase and stable data communication phase. In the stage of cluster building, the adjacent nodes cluster dynamically and randomly generate cluster heads. In the data communication phase, the nodes in the cluster send the data to the cluster head, and the cluster head performs data fusion and sends the results to the aggregation node. Because the cluster head needs to complete data fusion, communication with the convergence node and other works, the energy consumption is large. Leach algorithm can ensure that each node acts as cluster head with equal probability, so that the nodes in the network consume energy relatively evenly. The basic idea of Leach algorithm is to randomly select cluster head nodes in a circular way. It evenly distributes the energy load of the whole network to each sensor node in the network. It can reduce network energy consumption and improve network life cycle. Leach repeatedly performs cluster refactoring during its operation. This paper studies the parameter detection of wireless sensor network based on Leach algorithm on the on-chip embedded debugging system. Because the classical low-power adaptive clustering layered protocol (Leach) has the problem of energy imbalance and short node life cycle, this paper uses embedded debugging technology based on Leach algorithm and the residual energy and position of nodes in wireless sensor networks were tested for research. This Leach algorithm uses the concept of wheel. Each round consists of two phases: initialization and stabilization. In the initialization stage, each node generates a random number between 0 and 1. If the random number generated by a node is less than the set threshold T (n), the node publishes a message that it is a cluster head. Through the research on the parameter detection, the simulation results show that the research in this paper has good feasibility and rationality. [ABSTRACT FROM AUTHOR]

This paper proposes a new virtual interaction based programmable logic controller (PLC) training system using virtual sensors and actuators. The proposed system is composed of four components including virtual sensors (for interacting between user and input devices), virtual actuators (for manipulating and controlling device or equipment), virtual PLC (for programming and generating command), and virtual networks (for interfacing the interactions and transferring the data between all the components). The proposed system is applied to a real training program of the university's training center to examine the applicability and feasibility, and the results are analyzed and discussed. [ABSTRACT FROM AUTHOR]

In underwater acoustic sensor networks (UASNs), the propagation delay of acoustic signals is much longer than Radio Frequency (RF). There is spatial unfairness problem caused by space-time uncertainty. Hence, the design of Medium Access Control (MAC) is a challenging issue. In underwater, it not only considers transmission time but also takes location into account. In this paper, we propose Response to the Earliest Transmitter of RTS MAC (RET-MAC) protocol to solve the problem. RET-MAC adopts adaptive RTS Contention Phase (RTS CP) to determine the earliest transmitter of RTS. And CTS Delay Phase (CTS DP) is added to postpone sending CTS in order to avoid collision. In addition, we propose CTS back-off mechanism to adjust the length of CTS DP as needed. Contention back-off mechanism is used to reduce network congestion and increase fairness further. The simulation results show that our scheme can achieve higher fairness and throughput; at the same time it also guarantees lower energy consumption and delay. [ABSTRACT FROM AUTHOR]

Mobile sensor networks (MSNs) are widely used in various domains to monitor, record, compute, and interact the information within an environment. To prolong the life time of each node in MSNs, energy model and conservation should be considered carefully when designing the data communication mechanism in the network. The limited battery volume and high workload on channels worsen the life times of the busy nodes. In this paper, we propose a new energy evaluating methodology of packet transmissions in MSNs, which is based on redividing network layers and describing the synchronous data flow with matrix form. We first introduce the cache coherence layer to the protocol stack of MSNs. Then, we use a set of energy probability matrices to describe and calculate the energy consumption of each state in the protocol. After that, based on our energy model, we will give out an energy evaluating method of the MSNs design, which is suitable for measuring and comparing the energy consumption from different implements of hardware/software. Our experimental results show that our approach achieves a precision with less than 2% error and provides a credible quantitative criterion for energy optimization of data communication in MSNs. [ABSTRACT FROM AUTHOR]

Wireless Sensor Networks (WSNs) provide a wireless network infrastructure for sensed data transport in environments where wired or satellite technologies cannot be used. Because the embedded hardware of the sensor nodes has been improved very much in the last years and the number of real deployments is increasing considerably, they have become a reliable option for the transmission of any type of sensed data, from few sensed measures to multimedia data. This paper proposes a new protocol that uses an ad hoc cluster based architecture which is able to adapt the logical sensor network topology to the delivered multimedia stream features, guaranteeing the quality of the communications. The proposed protocol uses the quality of service (QoS) parameters, such as bandwidth, delay, jitter, and packet loss, of each type of multimedia stream as a basis for the sensor clusters creation and organization inside the WSN, providing end-to-end QoS for each multimedia stream. We present real experiments that show the performance of the protocol for several video and audio cases when it is running. [ABSTRACT FROM AUTHOR]