The corresponding development of resonance mass beam pressure sensor in decades is introduced and a serial of theory analysis is executed. The advantages and disadvantages are studied on the resonance mass pressure sensor. Through the finite element analysis software ANSYS, the stress and strain distribution situation is obtained in this paper. Under the outside overload pressure situation, we find that the linearity of the resonance mass beam pressure sensor presents a declining situation, but in a small range. From the total performances of sensor, it still keeps a good condition. Under the 260 times of rang pressure, the sensor chip deformation is only 14.5um, which is a kind of very small deformation situation. That is to say the resonance polycrystalline silicon mass beam sensor designed here has a high reliability under the outside overload pressure situation.

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Early warning system of water resources security is a multi-level and complex system made of many factors. By analyzing current situation of water resources security early warning, operating mechanism of water resources security early warning system is put forward. Logic, time and knowledge related to operating mechanism are discussed. For early warning threshold decision is one of key technologies in water resources security early warning, warning threshold decision and warning degree classification of water resources security early warning are set forth. These methods are systematic method, control chart method, catastrophe theory method and expert decision method. Adopting the water resources security early warning system, situation can be analyzed and predicted promptly and effectively.

Multistage open association (MSOA) and helical growth (HG) mechanisms describe the linear growth of supramolecular polymer chains and the helical growth of supramolecular chains with the intra-assemble cooperative effect, respectively. Both mechanisms were proposed by Ciferri. Assuming that supramolecular polymerization follows the step-growth and the interaction between repeat units is independent of molecular weight, the kinetics of MSOA and HG can be mathematically analyzed. In this paper the relationships among degree of polymerization (DP), unimer concentration (C0), and equilibrium constant (K) for MSOA and DP , concentration of helical polymer ( h C ), and nucleation factor (σ ) for HG were derived.

Relaying protection is very important for electric system, in order to ensure electric system normal usage, the safeguard procedures are needed. The protective relaying is main and active manner. The protective relaying significance and equipment employments and maintain is analyzed in this paper, and protective relaying technology developing prospect is also introduced in this paper.