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51.
尽管许多人可能并没有意识到,各类卡已经被广泛应用到我们的日常生活当中。其中,信用卡,现金卡,驾驶执照,等等,其实与钱包同等重要。为了防止这些卡被非法使用,用户认证是必不可少的。最常用的用户认证方法就是要求用户提供某些个人信息。如果用户提供的信息与卡中记录的信息一致,我们就认为用户是合法的。然而如果个人信息被泄露,卡就有可能被非法使用。本论文的目的就是要提供一种新的基于图像变形的卡用户认证方法。其基本思路是把真正持卡人的脸部图像通过图像变形隐藏到某个覆盖数据下,并把恢复原图像所需要的钥匙信息分散保存到卡,终端,服务器等不同地方。在用户使用卡的时候,认证系统可以利用反变形技术恢复原图像,让受权人察知到用户的真伪,从而有效地保护持卡人的权益。 相似文献
52.
为了提高信息系统统一用户管理水平,结合当前信息系统应用现状,系统的介绍了统一用户认证系统4A架构、功能模块等的设计及实现方法,阐述了统一用户管理系统部署环境和应用效果,对于企业统一用户权限管理具有一定的借鉴意义。 相似文献
53.
随着非侵入式电力负荷监测的发展,如何利用用户负荷用电细节信息,分析用户用电行为特征成为重要的研究方向。本文提出了基于非侵入式负荷监测的用户行为精细化分析方法,根据历史数据建立用户行为特性指标,提出基于因子分析与支持向量机的用户聚类方法。在此基础上,建立基于精细化负荷数据的用户需求响应潜力评估指标。算例结果表明,所研究内容可以准确分析用户行为,为电力公司施行需求侧管理提供科学指导。 相似文献
54.
大学生求学满意度实证研究--某高校学生个体特征对满意度单项要素的影响分析 总被引:1,自引:0,他引:1
求学满意度,又称为求学满意程度,它取决于教育需求主体对教育服务的预期同其实际所感知的教育服务水平的对比。教学计划、教学组织、教师教学、教学设施、校园环境、学生5知识技能等都是影响求学满意度的因素。本文在调查取得基本数据的基础上,使用相关的统计检验方法,分析了性别、生源地和不同年级这些学生个体地征对求学满意度单项要素的影响。主要结论有:学生性别差异对满意度单项要素的影响基本是随机的;不同生源地的学生对教学计划和管理制度两个要素的评价具有差异;不同年级的学生对教学设施和知识掌握程度的评价具有显著性差异;学生对学校服务评价单项因素差异很少,总体满意度在一定程度上反应学校的实际情况。 相似文献
55.
《Expert systems with applications》2014,41(1):69-80
This paper attempts to study the impact of customer satisfaction and the Chinese electronic retailers (E-retailers) competitiveness using quality factors. Two conceptual models based on asset-process-performance (APP) competitive theoretical framework have been proposed. The proposed models include E-retailers strategic factors such as logistics, quality and customer satisfaction equivalent to asset, process and performance entities of the APP framework. Using an empirical survey from a young population, this study, with the support of structural equation modeling (SEM) identifies reliability in service quality and purchasing experience in e-service quality as dominant customer satisfaction factors. This study uses both exploratory and confirmatory factor analysis and suggests that to be competitive Chinese E-retailers have to focus more on the delivery of products (logistics) compared to other intangible service quality factors. On theoretical front, this study is a novel attempt to validate the APP framework for E-retailers’ competitiveness. On the practical front, the outcome of the study would be highly beneficial to the Chinese E-retailers to fine tune their strategy to satisfy the growing demand. Furthermore, this study can supplement government policy makers to regulate the growing volatile market. 相似文献
56.
Fluid flow in coupled free and porous domain, particularly when the porous medium is heterogeneous, is encountered in many hydro-environmental conditions, e.g., leakage from underground pipe, combined groundwater lake-subsurface interactions. One of the most difficult problems in the study of coupled flow behaviour has been the development of a universally applicable modelling scheme for combining the flow regimes. This is because the free/porous interfacial properties (e.g., shear-stress; velocity slip) that govern the coupled flow behaviour are difficult to determine experimentally under hydro-environmental conditions. On the other hand, the implications of various forms of heterogeneity in the porous media properties can be very different on the fluid-flow behaviour. Difficulties may also arise in direct coupling of the model equations that govern the fluid flow in the individual regions (e.g., Navier-Stokes for free-flow region and the Darcy's equation for the porous flow region). Consequently, models of coupled free and porous flow for hydro-environmental conditions are not very well developed at the moment. While there are some indications that fluids in coupled free and porous domains may circulate (i.e., development of flow cells), there is a lack of appropriate 3D analysis on how heterogeneities in porous media may affect such flow patterns. In this paper, we aim to analyse how porous media heterogeneity affects the dynamics of flow circulation in the porous side of a coupled free and porous domain. For this purpose, we analyse flow patterns in several model domains made up of two porous layers with differing permeabilities. The governing model equations are discretised and solved using the standard finite volume method on a staggered cell-centred mesh. The temporal discretisation is done using the explicit method. An in-house graphical user interface (GUI) has been created specifically to aid in the visualisation of otherwise complex flow patterns. The GUI contains many post-processing options and provides a comprehensive tool for the analysis of hydrodynamics and contaminant motion (not discussed in this paper) in coupled free and porous flow domains. This GUI is described in this paper briefly. The effects of altering the aspect ratio (i.e., multi-scale) of the domain on the coupled flow pattern have also been discussed. 相似文献
57.
Chengjun Yao Yixun Liu Jianhua Yao Dongxiao Zhuang Jinsong Wu Zhiyong Qin Ying Mao Liangfu Zhou 《Computer methods and programs in biomedicine》2014
Background
Preoperatively acquired diffusion tensor image (DTI) and blood oxygen level dependent (BOLD) have been proved to be effective in providing more anatomical and functional information; however, the brain deformation induced by brain shift and tumor resection severely impairs the correspondence between the image space and the patient space in image-guided neurosurgery.Method
To address the brain deformation, we developed a hybrid non-rigid registration method to register high-field preoperative MRI with low-field intra-operative MRI in order to recover the deformation induced by brain shift and tumor resection. The registered DTI and BOLD are fused with low-field intra-operative MRI for image-guided neurosurgery.Results
The proposed hybrid registration method was evaluated by comparing the landmarks predicted by the hybrid registration method with the landmarks identified in the low-field intra-operative MRI for 10 patients. The prediction error of the hybrid method is 1.92 ± 0.54 mm, and the compensation accuracy is 74.3 ± 5.0%. Compared to the landmarks far from the resection region, those near the resection region demonstrated a higher compensation accuracy (P-value = .003) although these landmarks had larger initial displacements.Conclusions
The proposed hybrid registration method is able to bring preoperatively acquired BOLD and DTI into the operating room and compensate for the deformation to augment low-field intra-operative MRI with rich anatomical and functional information. 相似文献58.
59.
60.
Today's news readers can be easily overwhelmed by the numerous news articles online. To cope with information overload, online news media publishes timelines for continuously developing news topics. However, the timeline summary does not show the relationship of storylines, and is not intuitive for readers to comprehend the development of a complex news topic. In this paper, we study a novel problem of exploring the interactions of storylines in a news topic. An interaction of two storylines is signified by informative news events that play a key role in both storylines. Storyline interactions can indicate key phases of a news topic, and reveal the latent connections among various aspects of the story. We address the coherence between news articles which is not considered in traditional similarity-based methods, and discover salient storyline interactions to form a clear, global picture of the news topic. User preference can be naturally integrated into our method to generate query-specific results. Comprehensive experiments on ten news topics show the effectiveness of our method over alternative approaches. 相似文献