Xu Lizhong

The Application of Wireless Sensor Network in the Irrigation Area Automatic System

In the irrigation area automatic system, high- performance embedded micro-controller and low-power technology is used to design the water wireless sensor network. The sensor node gathers the hydrographic information such as water-level, gate position and rainfall. The sink node receives the real-time data; the information center stores and processes those data which are transmitted from the sink node through the GPRS network. The system replaces the wired transmission with the wireless transmission, which reduces the costs in installment and maintenance, and improves the system’s reliability and extension. It has better application prospect.

Fault Tolerance and Transmission Delay in Wireless Mesh Networks

Wireless mesh networks (WMNs) consist of mesh routers and mesh clients, where mesh routers have minimal mobility and form the backbone of WMNs. They provide network access for both mesh and conventional clients. Wireless mesh networks is put forward as one important technology of the access of various broadband. The integration of WMNs with other networks such as the Internet, cellular, IEEE 802.11, IEEE 802.15, IEEE 802.16, sensor networks, etc., can be accomplished through the gateway and bridging functions in the mesh routers. In this paper, we will discuss the fault-tolerant and transmission delay in the wireless mesh networks by topological property of undirected graph, and provide one measure to analysis the performance of wireless mesh networks.

A data-driven adaptability control method on the complex system of water resources

Aiming at solving the problems existing in the research of water resources regulation and management under the changing environment, the paper establishes a new paradigm taking the case of HongRu He river basin in China as an example. The paradigm is based on Complex Adaptive System (CAS) theory, data-driven technology and multi-agent computation technology, breaking the model of single agent and static controlling. The paper establishes a feedback-closed cycle model which includes three parts, such as data acquisition and processing, data-driven model discovery and performance recognition and data-driven regulation and output. Then the paper designs a kind of water adaptability dynamic control strategy based on active initiative and emergency intervention control. It includes: (1) modeling of water resources evolution system based on CAS; (2) a paradigm of water complex system of computer simulation analytical and adaptive control; (3) a scheme designed for the regulation and system behavior evaluation.

Multi-sensor multi-OOSM distributed sequential fusion filtering

Multi-sensor fusion for OOSM system is still an open question in the field of wireless sensor network. In this paper, a new distributed sequential fusion algorithm for multi-sensor system with one-step-lag OOSMs is proposed in the sense of minimum trace of error covariance matrix. The main idea of this real time sequential fusion algorithm is that: firstly, an equivalent measurement “sampled” at the fusion time is obtained, once a measurement comes to the fusion center; then, a local estimation of the current state is obtained based on the equivalent measurement; furthermore, first round fusion is carried out for the second local estimate and the first local estimate to obtain the first local fusion when the second measurement comes; another round of fusion process is carried out for the third local estimate and the first local fusion estimation. Repeating this process until all the measurements are fused, sequentially. The final simulation illustrates its efficiency and validity of the proposed method.