A typical pulsed thermography procedure results in a sequence of infrared images that reflects the evolution of temperature over time. Many features of defects, such as shape, position, and size, are derived from single image by image processing. Hence, determining the key frame from the sequence is an important problem to be solved first. A maximum standard deviation of the sensitive region method was proposed, which can identify a reasonable image frame automatically from an infrared image sequence; then, a stratagem of image composition was applied for enhancing the detection of deep defects in the key frame. Blob analysis had been adopted to acquire general information of defects such as their distributions and total number of defects. A region of interest of the defect was automatically located by its key frame combined with blob analysis. The defect information was obtained through image segmentation techniques. To obtain a robustness of results, a method of two steps of detection was proposed. The specimen of polyvinyl chloride with two artificial defects at different depths as an example was used to demonstrate how to operate the proposed method for an accurate result. At last, the proposed method was successfully adopted to examine the damage of carbon fiber-reinforced polymer. A comparative study between the proposed method and several state-of-the-art ones shows that the former is accurate and reliable and may provide a more useful and reliable tool for quality assurance in the industrial and manufacturing sectors.

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Genetic algorithm based on good character breed is presented, which imitates breeding good character seeds in biology. Genetic algorithm runs several times to build a seed set. Searching space of traveling salesman problem is rationally divided into segments based on the fine seed, for it is similar as optimum in structure. Evolution strategy combines with cut algorithm for the better resolution of large-scale TSP. The technique of open routing optimization and the technique of overlapping segments are used to solve the problem of end points of segments connection and optimization. The processes using the algorithm for eil101 and ch150 in TSPLIB give examples how to solve TSP. The results show that the genetic algorithm based on good character breed for TSP is efficient.

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