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Objective: The paper aims to establish the prediction model of urban power grid short-term load based on BP neural network algorithm. Method: Five factors influencing the urban power grid short-term load are used to establish the neural network model: date type, weather, daily maximum temperature, daily minimum temperature and daily average temperature. Matlab toolbox is used to develop the testing platform through VC++ programming. Result: The variable learning rates are 0.35 and 0.64. With 23410 iterations, the model is converged, and the global error is 0.00032. Conclusion: Through the data comparison and analysis, the relative error is within 5%, thus indicating the model is accurate and effective, and it can be used to predict the change of urban power grid short-term load.

In this study the accurate calibration technique of microscopic image was studied. A set of method which could accurately calibrate the microscopic images was established through construction of mathematic models for Lens distortion correction, binaryzation, and edge extraction etc. Experiments results indicates that, this method owns characteristics of small error, high recognition rate, fast calculation speed, and could finish calibration of microscopic images relatively accurately.

Objective: In this study, wheat dough rheological property changes caused by water-soluble dietary fiber were investigated. Methods: Capillary Rheometer and Extensional Rheometer were used to detect dough samples with water-soluble dietary fiber in different concentrations. Results: Water-soluble dietary fiber affects dough rheological properties both in strength and resistance. Conclusion: When water-soluble dietary fiber concentration increased, dough became softer but stability and stir tolerance decreased.

Juvenile turbot (Scophthalmus maximus) were exposed to acaricide fenpyroximate, and the subsequent histological, enzyme activity changes of liver tissue were examined. Histopathological examinations showed that the turbot liver is the target organ for the acaricide fenpyroximate. Analysis of liver antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), in the exposed turbots also showed similar changes. These changes indicated that fenpyroximate caused the oxidative stress on the turbot liver, which induced the damage of antioxidant enzymes system and possible interruption of the mitochondrial redox respiratory chain. This could be one toxic mechanism of fenpyroximate to the juvenile turbot.

In this project, the utility of virtual environment modeling techniques based on geometric model on modeling street virtual reality systems was studied. The aim is to design a set of modeling streetscape system based on virtual reality systems. In designation phase, this system was based on computer graphics, and virtual environment entities were set up modeled by real entities in life. In the study, the East and West Huashi Street in Chongwen district was taken as a study area, the model of the scene was set up by virtual reality geo-information system, special virtual reality modeling software Multigen Creator was used to set up the 3D environment of the space, and the virtual reality scene was set up with advanced C language and called Vega function library, so that interactive manipulation of boosting, reducing, turning, searching and roaming of the virtual scene could be realized.