基于RSA等算法软件加密技术的研究与实现

本文对数据加密算法DES和RSA进行了详细的分析，并利用数据加密DES和RSA算法结合机器硬件指纹、钥匙盘等技术对软件进行混合加密并进行了实现，为各种商品软件加密提供了一种安全、简便、实用、廉价的加密方法，并能有效的防止软件被盗版。     

基于方向图的指纹奇异点快速检测方法

准确、快速地检测指纹奇异点(core点和delta点),对指纹分类和指纹匹配等具有重要意义.首先,给出计算指纹图像方向图的算法,然后,在基于方向图的基础上,对传统的基于poincare索引计算公式的指纹奇异点检测算法进行了改进.使用改进算法对PU-JY203U警用活体指纹采集仪采集的指纹(1000枚)进行Matlab仿真.实验结果表明改进后的算法与传统算法相比,在定位奇异点的精确度和速度上都有很大的提高.     

A secure fingerprint template generation mechanism using visual secret sharing with inverse halftoning

Fingerprints are the most popular and widely practiced biometric trait for human recognition and authentication. Due to the wide approval, reliable fingerprint template generation and secure saving of the generated templates are highly vital. Since fingers are permanently connected to the human body, loss of fingerprint data is irreversible. Cancelable fingerprint templates are used to overcome this problem. This paper introduces a novel cancelable fingerprint template generation mechanism using Visual Secret Sharing (VSS), data embedding, inverse halftoning, and super-resolution. During the fingerprint template generation, VSS shares with some hidden information are formulated as the secure cancelable template. Before authentication, the secret fingerprint image is reconstructed back from the VSS shares. The experimental results show that the proposed cancelable templates are simple, secure, and fulfill all the properties of the ideal cancelable templates, such as security, accuracy, non-invertibility, diversity, and revocability. The experimental analysis shows that the reconstructed fingerprint images are similar to the original fingerprints in terms of visual parameters and matching error rates.     

社保卡制作中高质量指纹图像提取

人的指纹特征不可复制，且具有唯一性、稳定性特点，用于居民的身份认证，能有效解决普通手段制作的社保卡安全性、防伪性较差问题。简要介绍社保卡制作的系统构成及技术难点，主要介绍高质量指纹图像的提取。它由前端指纹传感器、微处理器、指纹图像存储单元、接口单元等组成，采用图像搜索技术，通过改变指纹传感器芯片的电容阵列参数，能在1s内扫描多帧指纹图像，并自动选择图像质量最好的，保证社保卡的制作质量。实践证明，本方案能大大减低系统误识率FAR、拒识率FRR。     

Development and application of a functional CE-SSCP fingerprinting method based on [Fe–Fe]-hydrogenase genes for monitoring hydrogen-producing Clostridium in mixed cultures

A Capillary Electrophoresis Single Strand Conformation Polymorphism (CE-SSCP) method based on functional [Fe–Fe]-hydrogenase genes was developed for monitoring the hydrogen (H₂)-producing clostridial population in mixed-culture bioprocesses. New non-degenerated primers were designed and then validated on their specific PCR detection of a broad range of clostridial hydA genes. The hydA-based CE-SSCP method gave a specific and discriminating profile for each of the Clostridium strains tested. This method was validated using H₂-producing mixed cultures incubated at temperatures ranging from 25 °C to 45 °C. The hydA CE-SSCP profiles clearly differed between temperatures tested. Hence, they varied according to variations of the H₂ production performances. The HydA sequences amplified with the new primer set indicated that diverse Clostridium strains impacted the H₂ production yields. The highest performances were related to the dominance of Clostridium sporogenes-like hydA sequences. This CE-SSCP tool offers highly reliable and throughput analysis of the functional diversity and structure of the hydA genes for better understanding of the H₂-producing clostridial population dynamics in H₂ dark fermentation bioreactors.     

无线指纹识别技术在考试系统的应用研究

研究无线指纹识别问题,保证实时可靠,实现一个用于进行考试身份验证无线的指纹识别系统。利用嵌入式指纹终端采集考生的指纹,进行分割、增强、二值化等预处理后,通过CDMA无线网络将指纹特征发送给服务器进行匹配,指纹识别终端采用ARM9微处理器,MG815＋CMDA通信模块,μC/OS-II实时操作系统。对指纹识别中常用的二值化、细化、特征提取和特征匹配等关键算法进行了改进,对采用多级分割的分割算法、改进的Otsu的二值化算法、基于三角形全等的指纹特匹配算法。实验结果表明,系统平均耗费时间4.2s,平均匹配度为85.6%,系统响应时间和准确度基本能满足实际的要求。     

基于MD5和布鲁姆过滤器的重复数据删除算法

针对目前重复数据处理技术的低效性和不可靠性,本文提出了一种基于MD5算法和布鲁姆过滤器的重复数据删除算法。新算法采用两级布鲁姆过滤器并有效结合MDS算法的方式,在发挥布鲁姆过滤器空间效率的同时汲取了MD5算法的可靠性,使得文件级别和数据块级别的重复数据删除策略交替工作。测试分析表明,新算法性能稳定并且实现了高效且可靠的重复数据删除功能。     

Mixed fuel approach for the fabrication of TiO2:Ce3+ (1–9 mol%) nanophosphors: Applications towards wLED and latent finger print detection

TiO₂:Ce³⁺ (1–9?mol%) nanophosphors (NPs) were prepared by solution combustion method using combination of fuels. PXRD studies of pure and doped samples exhibit rutile and anatase phases respectively. SEM results indicate that the particles were found to be nearly spherical in nature. The energy band gap (E_g) of pure and doped samples was found to be in the range 3.10–3.23?eV. The active vibrational Raman modes observed at ～ 141, 446 and 608?cm^?1 were corresponds to B_1g, E_g and A_1g respectively. The mode at ～ 229?cm^?1 was due to second order effect that confirms the rutile phase of TiO₂. The CIE and CCT results of the doped TiO₂ shows that this product exhibits green colour (CIE-coordinates x = 0.3649, y = 0.4023) and was suitable for wLEDs which can be used for household applications. The optimized product was further utilized for the visualization of latent finger prints (LFPs) on various porous and non- porous surfaces. The results reveal that, all the levels (I–III) of ridge feature were clearly visualized under normal light indicating that the powder was a reliable and promising labeling agent for LFPs detection as well as wLED applications.     

A Fingerprint Minutiae Matching Method Based on Line Segment Vector

Minutiae-based fingerprint matching is the most commonly used in an automatic fingerprint identification system. In this paper, we propose a minutia matching method based on line segment vector. This method uses all the detected minutiae （the ridge ending and the ridge bifurcation） in a fingerprint image to create a set of new vectors （line segment vector）. Using these vectors, we can determine a truer reference point more efficiently. In addition, this new minutiae vector can also increase the accuracy of the minutiae matching. By experiment on the public domain collections of fingerprint images fvc2004 DID set A and DB4 set A, the result shows that our algorithm can obtain an improved verification performance.     

A content security protection scheme in JPEG compressed domain

The access and distribution convenience of public networks opens a considerable content security threat when sending, receiving, and using multimedia information. In this paper, a content security protection scheme that integrates encryption and digital fingerprinting is proposed to provide comprehensive security protection for multimedia information during its transmission and usage. In contrast to other schemes, this method is implemented in the JPEG compressed domain with no transcoding or decompression, therefore, this scheme is highly efficient and suitable for multimedia information, which is seldom available in an uncompressed form. In addition, a variable modular encryption method is proposed to solve the invalid variable length coding (VLC) problem when a compressed data stream is encrypted directly. Experimental results demonstrate improved security and the efficiency provided by the proposed scheme. The experiments also demonstrate imperceptibility and collusion resistance of fingerprints.