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A system for detecting the conditions of crop disease stress by acoustic emission technology was studied and developed .The PCI-2 acoustic emission board and R15 acoustic emission sensor probes were chosen to construct the hardware detecting system, and the AEWIN software and virtual instrument technology were utilized to construct the software system, a real-time acquisition and detecting system for the information between acoustic emission and disease stress of crop was established. The results show that there are a certain physiological cycle laws in the acoustic emission of healthy crop, generally the “double peak area” can appear; but distortion can occur in the acoustic emission of disease stressed crop, a sharp increase of the acoustic emission frequency can suddenly take place at some time, immediately the crop begins to show disease symptoms, and acoustic emission signals lose the regularity.

Basing on triaxial experiments, the paper conducts the research to Cemented Sand and Gravel constitutive model. Using virtual rigid spring method, the Cemented Sand and Gravel constitutive model with considering the softening characteristics of material is established, and parameters needed are determined, the model establishes the foundation of non-linear analysis of Cemented Sand and Gravel structure. Mechanical properties and constitutive model study of Cemented Sand and Gravel is key to Cemented Sand and Gravel faced eath-rockfill dam. Basing the Mechanical properties triaxial experiment of the material, the paper gives further discussion on the constitutive model of Cemented Sand and Gravel. From the results of the triaxial test, when the cemented material content is smaller than 20kg/m3, the stress strain curve agrees quite well with hyperbolic law to which the normal gravel test curve also obeys, the exception is the increase of shearing strength. If the cemented material content is more than 30kg/m3, there is a peak value on the stress strain curve, the curve (before peak value) shows that axial strain increase with deviatoric stress with the increment gradually changing slowly, i.e. the stress strain curve has obvious nonlinear feature. the curve peaks value at the axial strain =2％, the stress strain curve present softening pattern that deviatoric stress decreases with the strain increase if continuous applying axial load. When axial strain lies between 2% and 6%, the shearing strength of samples decreases rapidly, after this interval, the shear strength tends to the stable value in the final. It is core problem the paper try to solve that how to describe Cemented Sand and Gravel constitutive model.

As an important road detection system performance parameter, road rigidity was the key link and the evaluation index of the road detection system. During the construction of road infrastructure, the implementation of road worked on the hardness testing was necessary. The American National Instruments (NI)’s virtual instrument software development platform Lab VIEW was used as the system’s development platform. Through the signal collected by the pressure sensor combined with signal conditioning circuits formed by the single chip, functions of various parts were designed to analyze the relevant parameters of the road rigidity. The test data was measured and collected according to national standard methods, at the same time, virtual instrument software and related algorithms were used to analysis of the statistics data and the state of the road hardness would be detected and researched. And thus it provided an important basis for the quality of road management and road maintenance.

There are some disadvantages like that single-function and lower extent of automation in the electrical parameter detecting system of Jordan refiner, so its hard to adapt the system to the demand of the large-scale automatic detecting industry. Depending on the jordan refiner used in paper making, basing on the Labwindows/CVI software to be the host computer and the idea of virtual instrumentation, this devise constructed three-phase detecting system of the electrical parameter which using CS5460A power/energy computation chip for AD converter produced by Cirrus Logic company. The hardware construction and the software designing method are introduced; the concrete plan of enhancing the electrical parameter detecting precision is analyzed. The actual test suggests that the whole system is advantaged in high precision, fast speed, shot exploiting period and deeper extent of automation.