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排序方式: 共有469条查询结果,搜索用时 15 毫秒
91.
ZHANG Liang 《保鲜与加工》2002,(2):139-142
The mouse is developed with the purpose of providing reinforcement of database security for computer users, whose validity can be verified by taking advantage of the fingerprint identity, which is the uniqueness, immutability biological characteristic of human body. By one-by-one matching algorithm, rendering between pressured data and field acquisitions of finger print image, the vital heart of dactylogram verification with the mouse is realized. The mouse has been made possible by taking account of the roomy space within mouse,tiny chip patch for fingerprint identification and together with small size of available microprocessors. The mouse can be used as an normal pointing device while maintaining the capability of user identity distinguishing. The usage of this device is very easy and it is reliable. Development of this device mainly comprises of the hardware development, driver development, application software development, and the installation of network security verification center. The purpose, principle and system design of the mouse is introduced, while characteristics and applications of the device are also presented. 相似文献
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To study the fusion at feature extraction level for fingerprint and finger vein biometrics, a dynamic weighting matching algorithm based on predictive quality evaluation of interest features is proposed. The proposed approach is based on the fusion of the two traits by extracting independent feature point-sets from the two modalities, and making the two point-sets compatible for concatenation. According to the results of features evaluation, dynamic weighting strategy is introduction for the fusion biometrics. The weight of excellent features in fusion is improved, aiming to weaken the influence of low quality and false features so that better effects of fusion can be achieved. Experimental results based on FVC2000 and self-constructed databases of finger vein show that our scheme achieves 98.9% recognition rate, compared with fingerprint recognition and finger vein recognition increased by 6.6% and 9.6% respectively, compared with fusion recognition at matching level increased by 5.4%. 相似文献
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Based on multiple influencing factors, a new method of automatic fingerprint image quality evaluation is proposed for improving the success rate of automation fingerprint identification system (AFIS). At first, the original image’s local texture, global texture, available size and dry or wet condition are regarded as quality impact factors, local texture quality score is calculated by local gradient correlation, and then the last three factors’ quality scores are obtained by block computation thought. Then, with different influence weights, the above four impact factors are linked together to assess image quality synthetically. Finally, effect of partial impact factor is adjusted to correct the final quality score. FVC2004DB2_B is used for algorithm testing. The results suggest that this method can reasonably classify fingerprint image into 5 grades and the precision can achieve 97.5%, and that shows the method is helpful to success rate of AFIS. 相似文献
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为丰富瓠瓜分子标记库、开发瓠瓜SSR标记、寻找有效的瓠瓜种质资源鉴定方法,利用MISA软件对瓠瓜转录组测序获得的87 518条unigene序列进行筛选,共检测出11 029个SSR位点,发生频率为9.85%,分布距离为平均每8.3 kb有1个SSR 位点。其中只包含1个SSR位点的unigene 序列有6759条,其发生频率为7.72%;有1858条unigene序列含有2个及2个以上的SSR位点,发生频率为2.123%;有920条unigene序列属于混合形式的SSR标记,频率为1.051%。瓠瓜转录组中优势重复基序为单核苷酸、三核苷酸和二核苷酸,分别占总SSR位点的55.51%、25.41%和17.07%。A/T、AG/CT和AAG/CTT分别是单核苷酸、二核苷酸和三核苷酸的优势重复基元,分别占总SSR重复类型的98.22%、55.39%和39.86%。用Primer 3.0共设计出8617对SSR引物,利用6对条带清晰、多态性稳定的SSR引物构建了36个品种的指纹图谱,部分位点具有高度的一致性,说明基因来源范围较小。聚类分析显示,在相似系数为0.68时将36个瓠瓜品种分为6类。其表明我国瓠瓜品种资源遗传多样性非常狭窄,利用现有瓠瓜资源开展品种选育潜力有限,应加强对野生特异种质的引进与发掘利用。利用瓠瓜转录组数据进行SSR标记开发,获得的SSR位点能为其遗传多样性分析和遗传图谱构建提供更丰富可靠的标记选择。 相似文献
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为鉴定和保存不结球白菜品种资源,利用基因组 DNA 的 SRAP、RAPD 和 SSR-PCR 技术,筛选具有稳定多态性位点的引物,对新培育的耐热1号和苏州地区11个不结球白菜耐热主栽品种构建品种DNA 指纹,并转化为数字指纹图谱。结果表明:筛选出22个 SRAP 引物、16个 RAPD 引物和32个 SSR 引物,通过 PCR 扩增在12个白菜品种中获得了143个多态性位点标记,12个栽培品种间的遗传距离较小,相似系数范围为0.55~0.76。利用筛选出的3对 SRAP 引物组合成功绘制出不结球白菜主栽品种鉴定图,能将供试品种完全区分开。 相似文献
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利用DNA指纹鉴定玉米杂交种纯度及其真伪技术的研究 总被引:22,自引:2,他引:22
从500个随机引物中筛选出30个在玉米上具有较好多态性的RAPD随机引物,并进一步筛选确定了适合我国主要玉米杂交种及其双亲的特异引物,建立了相应的DNA指纹图谱。杂交种的DNA指纹图谱表现为父、母本双亲带型的互补,均未出现互补带型之外的新带型。应用RAPD技术获得DNA指纹图谱的方法可以简便、快捷、经济、准确地鉴别玉米杂交种子纯度及真伪。目前已进行了上百份的检测实践,无一差错。 相似文献
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