Sun Zhaoyun

Study of image-based pavement cracking measurement techniques

Cracking is one of the most common diseases that happen to the pavement and a field cracking survey and a forensic investigation are important work for preventive maintenance. In order to measure the pavement crackings automatically, this paper uses digital image processing techniques to process the pavement cracking images acquired by the digital camera and classify the pavement cracking types according to the topological properties to line crackings and alligator cracking, then classify the line crackings to longitudinal and transverse cracking according to the chain code of the cracking in the image. At the same time, the paper calculates the length and width of the line crackings and the area of the box rectangle of the alligator cracking. Finally, the paper calculates the Cracking Index (CI) of the pavement.

ADV212-based High Resolution Still Image Compression System Design

ADV212 is a SOC which is to implement JPEG2000 encoding and decoding. An embedded RISC processor, a dedicated wavelet transform engine, three entropy codec and on-chip memory system are integrated in ADV212. It provides a complete JPEG2000 compression and decompression solution for real-time application of standard or high resolution video or still image. The ADV212 implements the function described in the JPEG2000 Standard Part I except the ROI. Two chips of ADV212 are used to perform lossy and lossless compression of high resolution aero image. The system architecture is mainly discussed in the paper and also the software and hardware design method to use ADV212 to compress still image. The experimental results show that the system could implement real-time compression of high resolution aero image.

Notice of Retraction Teaching Highway Engineering Experiments by Visualization

The highway engineering experiments are of great importance for the key role it played in the highway construction process. But now the teaching and learning of the highway engineering experiment faces problems which result in the situation of the students cannot learn the experiment in the field. In order to solve the problems, this paper introduces the visualization techniques to the teaching and learning process of the highway engineering experiment. The paper reviews some of the current teaching methods and then describes the realization of the highway engineering experiments visualization in Adobe Flash CS4, the interactive between the visualization tool and the students is also realized by using the Actionscript. The visualization of the highway engineering experiment is a new method that worthy trying for its teaching effects and environmental effects.

The Web asynchronous communication mechanism research based on Ajax

Ajax implements data exchange between a client and a server though the asynchronous communication mechanism, which is a research hotspot belongs to a Series of web2.0 technology. This paper analyses the technical features of Ajax WEB communication mechanism, and apply it to the B / S structure of the teaching management system design. In practice, Web pages through the JavaScript call Asynchronous Ajax engine load data, not only lightened the burden on the server and bandwidth, and improve the user experience.