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According to the characteristics of piggery, such as complex environment, numerous control objects, complex wiring, a piggery environment control system based on wireless sensor networks was designed. This system consisted of the wireless network composed of various devices and sensors in piggery, the control center with ARM-LINUX and the remote control center. The energy of sensor nodes was offered by batteries in wireless sensor networks so that the power source was limited. In order to strengthen the node energy management, the LEACH algorithm was combined with AODV routing protocol, and a new optimization algorithm called LEACH-A was proposed in this paper. The wireless sensor networks execution process was divided into two phases, including cluster building and data transmission. In the two phases, the node residual energy was calculated by a weighted function and the cluster head role was changed by the size of remaining energy. NS-2 simulation results show that the proposed algorithm prolonged the lifetime of the nodes and the networks, and realized the energy optimization management.

In view of the fixed testing point and complex wiring in conventional piggery environment control, a new system based on wireless sensor network was designed. This system consisted of the control center with ARM-Linux, executing mechanism nodes and wireless sensor network containing the flexible sensor nodes which could be arbitrarily placed in piggery. In order to make reasonable use of the energy of Zigbee network and prolong the survival time, a improved zigbee tree routing algorithm was proposed. First of all, by analyzing the advantages and disadvantages of the Cluster-tree and AODVjr algorithm in the Zigbee protocol, the neighbor table was introduced into the improved algorithm. Secondly, the scope of the destination node was confirmed to control the radio range of the RREQ and prevented invalid RREQ flooding. Simulation results show that the improved algorithm optimized the overall energy consumption effectively, prolonged the time of the critical nodes, reduced the number of death nodes, balanced the network load and improved the overall performance of the network.

The objective of this work was to discuss a calculation method of dye concentration in mixed dye bath, to develop an optical fibre sensing system for in-situ monitoring of dye concentrations in a dye bath and control the rate of exhaustion to ensure that the dyeing process yields the desired product. A designed optical fibre sensing system was proved to be practicable to measure the single dye concentration accurately, it is important to chance right calculation method in measuring mixed dye bath concentration. The experiment prepared known concentration mixture with reactive red 2G and yellow 4G. Based on measured absorption spectra, dyes concentrations were calculated by derivative ratio method. The calculated results were compared with the prepared concentrations. The accuracy was discussed. The results show that calculated dyes concentration by derivative ratio method well matched the prepared value at the certain concentration range.

Based on measured ventilation condition in the built aerobic composting plant of large sludge treatment engineering,using the methord of CFD, four kinds of scheme for the new aerobic composting plant were analysed,which contain two types of ventilation(natural air supply mechanical exhaust and mechanical air mechanical ventilation)and two kinds of supply air rates (4x105m3/h and 8x105m3/h). Studies have shown that the methord of mechanical air supply and exhaust is better than the original natural air mechanical exhaust in this plant; The methord of mechanical air supply and exhaust is recommended to reduce ammonia content for personal breathing zone and ventilation energy consumption.

A new hexagonal actuator arrangement continuous face-sheet MEMS deformable mirror is proposed, a mirror array with 19 elements is fabricated by a surface micromachining process. This design has a good fitting capability and a fast dynamic response. The fabricated sample is tested by an optical profiler. Simulation and test results indicate that it has a small aperture size, a high fill factor, a fast response time and a high working bandwidth. This new device provides a possibility of manufacturing a large-actuator-count DM for high speed wavefront control.

We present an algorithm to compute Minkowski sum of general ployhedra, the algorithm removes unnecessary information of computing pairwise Minkowski sum by redundancy analysis and adopt heuristic sorting order to improve computing efficiency of union process, contrast experiments show the algorithm is efficient and suitable for CAD and CAM.