Recently, a cryptographic construct,called fuzzy vault, has been proposed for crypto-biometric systems, and some implementations for fingerprint have been reported to protect the stored fingerprint template by hiding ...Recently, a cryptographic construct,called fuzzy vault, has been proposed for crypto-biometric systems, and some implementations for fingerprint have been reported to protect the stored fingerprint template by hiding the fingerprint features. However, all previous studies assumed that fingerprint features were pre-aligned, and automatic alignment in the fuzzy vault domain is a challenging issue.In this paper, an auto-aligned sharing fuzzy fingerprint vault based on a geometric hashing technique is proposed to address automatic alignment in the multiple-control fuzzy vault with a compartmented structure. The vulnerability analysis and experimental results indicate that, compared with original multiplecontrol fuzzy vault, the auto-aligned sharing fuzzy fingerprint vault can improve the security of the system.展开更多
Estimation of the far-field centre is carried out in beam auto-alignment. In this paper, the features of the far-field of a square beam are presented. Based on these features, a phase-only matched filter is designed, ...Estimation of the far-field centre is carried out in beam auto-alignment. In this paper, the features of the far-field of a square beam are presented. Based on these features, a phase-only matched filter is designed, and the algorithm of centre estimation is developed. Using the simulated images with different kinds of noise and the 40 test images that are taken in sequence, the accuracy of this algorithm is estimated. Results show that the error is no more than one pixel for simulated noise images with a 99% probability, and the stability is restricted within one pixel for test images. Using the improved algorithm, the consumed time is reduced to 0.049 s.展开更多
Auto-alignment is a basic technique for high-power laser systems. Special techniques have been developed for laser systems because of their differing structures. This paper describes a new sensor for auto-alignment in...Auto-alignment is a basic technique for high-power laser systems. Special techniques have been developed for laser systems because of their differing structures. This paper describes a new sensor for auto-alignment in a laser system,which can also serve as a reference in certain applications. The authors prove that all of the beam transfer information(position and pointing) can theoretically be monitored and recorded by the sensor. Furthermore, auto-alignment with a single lens sensor is demonstrated on a simple beam line, and the results indicate that effective auto-alignment is achieved.展开更多
文摘Recently, a cryptographic construct,called fuzzy vault, has been proposed for crypto-biometric systems, and some implementations for fingerprint have been reported to protect the stored fingerprint template by hiding the fingerprint features. However, all previous studies assumed that fingerprint features were pre-aligned, and automatic alignment in the fuzzy vault domain is a challenging issue.In this paper, an auto-aligned sharing fuzzy fingerprint vault based on a geometric hashing technique is proposed to address automatic alignment in the multiple-control fuzzy vault with a compartmented structure. The vulnerability analysis and experimental results indicate that, compared with original multiplecontrol fuzzy vault, the auto-aligned sharing fuzzy fingerprint vault can improve the security of the system.
基金Project supported by the National High Technology Research and Development Program of China (Grant No 007SQ804)Japan-Korea-China Cooperative Project on High Energy Density Science for Laser Fusion Energy
文摘Estimation of the far-field centre is carried out in beam auto-alignment. In this paper, the features of the far-field of a square beam are presented. Based on these features, a phase-only matched filter is designed, and the algorithm of centre estimation is developed. Using the simulated images with different kinds of noise and the 40 test images that are taken in sequence, the accuracy of this algorithm is estimated. Results show that the error is no more than one pixel for simulated noise images with a 99% probability, and the stability is restricted within one pixel for test images. Using the improved algorithm, the consumed time is reduced to 0.049 s.
文摘Auto-alignment is a basic technique for high-power laser systems. Special techniques have been developed for laser systems because of their differing structures. This paper describes a new sensor for auto-alignment in a laser system,which can also serve as a reference in certain applications. The authors prove that all of the beam transfer information(position and pointing) can theoretically be monitored and recorded by the sensor. Furthermore, auto-alignment with a single lens sensor is demonstrated on a simple beam line, and the results indicate that effective auto-alignment is achieved.