A Target-Orientated Marker Image Binarization Method for Orthopaedic Surgical Navigation System

Camera calibration is the key technique in a C-arm based orthopaedic surgical navigation system. The extraction of marker location information is a necessary step in the calibration process. Ideal marker images should possess uniform background and contain marker shadow only, but in fact marker images always possess nonuniform background and are contaminated by noise and unwanted anatomic information, making the extraction very difficult. A target-orientated marker shadow extraction method was proposed. With this method a proper threshold for marker image binarization can be determined.     

关于发展中国经济型轿车若干问题的思考

本文叙述当发展面向中国家庭消费的经济型轿车时，在市场，车型，运行环境和可持续发展诸方面应考虑的问题。     

关于发展中国经济型轿车若干问题的思考

本文分析了中国汽车工业的总体经济实力，指出中国东部地区汽车工业和轿车市场将率先得到发展，并提出发展中国经济型轿车的若干问题。