共查询到20条相似文献,搜索用时 31 毫秒
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为了更好地进行图像数字水印的识别,基于对数极坐标仿射(LPM),设计和应用了5种滤波器,即经典匹配滤波器、振幅滤波器、相位滤波器、双态相位滤波器和改进的滤波器。为比较各种滤波器对数字水印的识别能力,将这些滤波器对嵌入图像中的数字水印进行了两种情况的检测实验。实验结果表明,当含数字水印的图像没有几何失真,即没有旋转、缩小和放大、平移等变化时,改进的滤波器、相位滤波器和双态相位滤波器均能对图像中的数字水印进行识别,改进的滤波器在图像数字水印检测中的识别能力要强于相位滤波器和双态相位滤波器;当含数字水印的图像发生微小几何变化,即旋转10°和尺寸缩小为原图像的0 9时,则传统的4种滤波器都不能对图像中的数字水印进行识别,但改进的滤波器仍具有对图像中数字水印进行识别的能力。 相似文献
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泛逻辑学中UB代数系统的滤子与商代数 总被引:1,自引:1,他引:0
给出了理想状态下泛逻辑学的形式演绎系统,证明了此系统是可靠的。提出了在理想状态(h=k=0.5)下泛逻辑学对应的代数系统-UB代数,进一步讨论了UB代数滤子与商代数,得到一些有用的结果。 相似文献
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P. Cintula 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2001,5(3):243-244
This short paper has two goals. The first is to show a new axiomatic system of product fuzzy logic with only one non-BL axiom
which has only two variables. The second goal is to prove that there cannot be any axiomatic system of the product fuzzy logic
with single non-BL axiom with only one variable. 相似文献
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Restoring subsampled color images 总被引:1,自引:0,他引:1
In some capturing devices, such as digital cameras, there is only one color sensor at each pixel. Usually, 50% of the pixels
have only a green sensor, 25% only a red sensor, and 25% only a blue sensor. The problem is then to restore the two missing
colors at each pixel – this is called “demosaicing”, because the original samples are usually arranged in a mosaic pattern.
In this short paper, a few demosaicing algorithms are developed and compared. They all incorporate a notion of “smoothness
in chroma space”, by imposing conditions not only on the behavior of each color channel separately, but also on the correlation
between the three channels. 相似文献
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Error-free software in large applications may be possible only by respecifying the original design-and may be affordable only when automatic tools become available. 相似文献
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Industrial fault diagnosis can be supported by assistance systems that infer fault causes from sensor data. The present study asked what information these algorithms should make available to operators. In a computer‐based experiment about fault diagnosis in a packaging machine, three information presentation strategies were compared regarding their impacts on information sampling, performance, and knowledge acquisition: Providing only sensor data, sensor data along with three possible interpretations, or only the most likely interpretation. Before submitting a diagnosis, participants could sample process parameters, one of which indicated the fault cause. We hypothesized that providing only sensor data would lead to more parameter checking and slower solutions than interpretations. While providing only one interpretation was expected to enable efficient performance for correct interpretations, it should lead to either of two types of performance costs for incorrect interpretations: Errors if participants refrain from checking parameters, or slowdowns in performance if they keep on checking. The results confirmed that participants with only sensor data performed inefficiently. Participants with only one interpretation thoroughly checked parameters but still were fastest when the interpretation was correct, while when it was incorrect they were three times slower than participants with only sensor data. Participants with three interpretations (one of which was always correct) performed almost as efficiently as those with only one correct interpretation. The results indicate that highly preprocessed information leads to efficient performance when it is correct but prevents learning about fault causes. Overall, providing several possible interpretations seemed to be the best strategy. 相似文献
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The root clustering property of a certain class of polytopes of polynomials is examined. It is shown that the polytopes of polynomials have only zeros within the left sector if and only if a subset of their edge polynomials has only zeros within the left sector. Certain conditions are derived under which the root clustering property of the polytopes of polynomials can be inferred from a subset of their vertices 相似文献
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一个基于RBAC的工作流授权模型 总被引:3,自引:0,他引:3
提出了一个基于RBAC的工作流授权模型RWAM,与传统的基于主体一客体的授权模型不同,该模型提出了时态权限的概念,表示只能在某个时问段内,对某个任务执行某种操作.这样不仅可以保证组成工作流的任务只能被属于某个特定角色的用户执行,而且可以保证授权流与工作流是同步的. 相似文献
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数据仓库的维护是数据仓库应用中的一个十分重要的问题,近几年产生了很多的维护算法。已有的维护算法多是针对单个实化视图的维护;或只针对简单SPJ视图的维护;或只针对聚集函数的维护;而实际的数据仓库大多是由包含聚集函数的多个实化视图组成。因此综合考虑包含聚集函数的多个实化视图的维护问题是必然的。文章正是在此情况下提出了一种基于多实化视图增量维护的基库生成算法,在《基于基库的多实化视图增量维护算法》中提出了包含聚集函数的多实化视图的维护算法。 相似文献
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基于RBAC的CSCD系统工作流授权模型 总被引:1,自引:0,他引:1
提出一个基于RBAC的CSCD系统工作流授权模型RTSWAM,与传统的访问控制授权模型不同,该模型在已提出的时态权限概念的基础上,提出了时空权限的概念,表示基于RBAC的CSCD系统工作流授权不仅受时间约束,还受空间范围限制,即被授权者只能在某个时间段和网络空间段内,才能对某个任务执行某种操作,这样不仅可以保证组成工作流的任务只能被属于某个特定角色的用户执行,而且可以保证在授权流与工作流同步的基础上,实现授权流与网络空间范围动态变化的协调一致。 相似文献
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Rigid body models with two controls cannot be locally asymptotically stabilized by continuous feedbacks which are functions of the state only. This impossibility no longer holds when the feedback is also a function of time, and time-varying asymptotically stabilizing feedbacks have already been proposed. However, due to the smoothness of the feedbacks, the convergence rate is only polynomial. In this paper, exponential convergence is obtained by considering time-varying feedbacks which are only continuous 相似文献
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Nicola Petrocchi Anu Asnaani Alejandra Piquer Martinez Ashwini Nadkarni 《International journal of human-computer interaction》2013,29(2):157-165
Facebook (FB) and Twitter are popular social networking sites. This study examined differences between those who use both sites versus only FB, to test the hypothesis that mono-users differ in their personality characteristics from users active in both websites. Participants were 205 undergraduate students: 96 only used FB, 109 used FB and Twitter. Participants who used both sites reported significantly lower loneliness, higher number of FB friends, and lower number of minutes spent online, as compared to those who used only FB. Loneliness was positively associated with FB use only in those who used FB alone but was negatively associated with and negatively predicted both FB and Twitter use in those who used both websites. Findings suggest that more intense use of online interactions is more frequently found in mono-users (people using only Facebook) as compared to those using both websites, and it is predicted by increased feelings of loneliness. The current study findings provide additional insights on what personality factors may make some people prone to excessive use of social networking sites. 相似文献
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Yoo Jaemin Kim Junghun Yoon Hoyoung Kim Geonsoo Jang Changwon Kang U 《Knowledge and Information Systems》2022,64(8):2141-2169
Knowledge and Information Systems - How can we classify graph-structured data only with positive labels? Graph-based positive-unlabeled (PU) learning is to train a binary classifier given only the... 相似文献
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In this paper, we present a recursive algorithm for extracting classification rules from feedforward neural networks (NNs) that have been trained on data sets having both discrete and continuous attributes. The novelty of this algorithm lies in the conditions of the extracted rules: the rule conditions involving discrete attributes are disjoint from those involving continuous attributes. The algorithm starts by first generating rules with discrete attributes only to explain the classification process of the NN. If the accuracy of a rule with only discrete attributes is not satisfactory, the algorithm refines this rule by recursively generating more rules with discrete attributes not already present in the rule condition, or by generating a hyperplane involving only the continuous attributes. We show that for three real-life credit scoring data sets, the algorithm generates rules that are not only more accurate but also more comprehensible than those generated by other NN rule extraction methods. 相似文献
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《IEEE transactions on pattern analysis and machine intelligence》1983,(3):314-322
A methodology has been proposed for solving database problems requiring only approximate solutions. Data items are classified as sensitive and nonsensitive. An approximate transaction modifies only the nonsensitive data items which need not satisfy strong consistency constraints, and provides results only up to a degree of approximation. Further, it is shown that such an approach improves the performance in situations where transaction conflicts are frequent. Additionally, the methodology provides users as well as data managers with mechanisms to control the precision of the computation, preserving the qualitative characteristics of the data items. 相似文献