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1.
Relevance feedback is a mechanism to interactively learn a users query concept online. It has been extensively used to improve the performance of multimedia information retrieval. In this paper, we present a novel interactive pattern analysis method that reduces relevance feedback to a two-class classification problem and classifies multimedia objects as relevant or irrelevant. To perform interactive pattern analysis, we propose two online pattern classification methods, called interactive random forests (IRF) and adaptive random forests (ARF), that adapt a composite classifier known as random forests for relevance feedback. IRF improves the efficiency of regular random forests (RRF) with a novel two-level resampling technique called biased random sample reduction, while ARF boosts the performance of RRF with two adaptive learning techniques called dynamic feature extraction and adaptive sample selection. During interactive multimedia retrieval, both ARF and IRF run two to three times faster than RRF while achieving comparable precision and recall against the latter. Extensive experiments on a COREL image set (with 31,438 images) demonstrate that our methods (i.e., IRF and RRF) achieve at least a
improvement on average precision and recall over the state-of-the-art approaches. 相似文献
2.
Thomas Burwick Author Vitae 《Neurocomputing》2011,74(9):1315-1328
A pattern recognition mechanism (“windowing mechanism”) is proposed that is based on Hebbian memory and oscillatory inhibition. It is related to properties of cortical gamma oscillations as expressed with the communication-through-coherence hypothesis. The rhythm dominating among excitatory units is imprinted on the inhibitory units through columnar couplings. Excitatory units that participate in the dominating rhythm may escape the feedback from the inhibitory pool through being active in the time windows given by the minima of the inhibitory effect. The activity of other units is suppressed. Constituting an excitatory rhythm that is compatible with the inhibitory one, the participating units comprise the winning patterns. This windowing mechanism is specified through giving an oscillatory network model and demonstrating it with image processing examples. Thereby, we also provide a gradient system formulation for inhibitory generation of synchrony. 相似文献
3.
Although using domain specific knowledge sources for information retrieval yields more accurate results compared to pure keyword-based methods, more improvements can be achieved by considering both relations between concepts in an ontology and also their statistical dependencies over the corpus. In this paper, an innovative approach named concept-based pseudo-relevance feedback is introduced for improving accuracy of biomedical retrieval systems. Proposed method uses a hybrid retrieval algorithm for discovering relevancy between queries and documents which is based on a combination of keyword- and concept-based approaches. It also uses a pseudo-relevance feedback mechanism for expanding initial queries with auxiliary biomedical concepts extracted from top-ranked results of hybrid information retrieval. Using concept-based similarities makes it possible for the system to detect related documents to users’ queries, which are semantically close to each other while not necessarily sharing common keywords. In addition, expanding initial queries with concepts introduced by pseudo-relevance feedback captures those relations between queries and documents, which rely on statistical dependencies between concepts they contain. As a matter of fact, these relations may remain undetected, examining merely existing links between concepts in an external knowledge source. Proposed approach is evaluated using OHSUMED test collection and standard evaluation methods from text retrieval conference (TREC). Experimental results on MEDLINE documents (in OHSUMED collection) show 21% improvement over keyword-based approach in terms of mean average precision, which is a noticeable gain. 相似文献
4.
基于虚拟相关反馈(PRF)技术,提出了一种新的自动关联反馈检索方法--外部自动相关反馈(OARF).该方法基于图像内容特征距离,应用K-均值聚类,自动扩展查询图像特征,从而提高检索性能.试验结果表明,OARF能够降低用户负担,显著提高原始检索算法的性能,缩小"语义鸿沟". 相似文献
5.
基于目标区域和相关反馈的图像检索 总被引:1,自引:0,他引:1
提出了一种基于目标区域和相关反馈的图像检索方法,首先采用改进的K均值无监督分割方法将图像分割成区域,然后提取每个区域的颜色、位置、形状特征进行相似度计算;最后采用基于支持向量机(SVM)的相关反馈算法提高检索精度。实验结果表明,方法具有良好的检索性能。 相似文献
6.
Synchronous rhythmic spiking in neuronal networks can be brought about by the interaction between E-cells and Icells (excitatory and inhibitory cells). The I-cells gate and synchronize the E-cells, and the E-cells drive and synchronize the I-cells. We refer to rhythms generated in this way as PING (pyramidal-interneuronal gamma) rhythms. The PING mechanism requires that the drive I(I) to the I-cells be sufficiently low; the rhythm is lost when I(I) gets too large. This can happen in at least two ways. In the first mechanism, the I-cells spike in synchrony, but get ahead of the E-cells, spiking without being prompted by the E-cells. We call this phase walkthrough of the I-cells. In the second mechanism, the I-cells fail to synchronize, and their activity leads to complete suppression of the E-cells. Noisy spiking in the E-cells, generated by noisy external drive, adds excitatory drive to the I-cells and may lead to phase walkthrough. Noisy spiking in the I-cells adds inhibition to the E-cells and may lead to suppression of the E-cells. An analysis of the conditions under which noise leads to phase walkthrough of the I-cells or suppression of the E-cells shows that PING rhythms at frequencies far below the gamma range are robust to noise only if network parameter values are tuned very carefully. Together with an argument explaining why the PING mechanism does not work far above the gamma range in the presence of heterogeneity, this justifies the "G" in "PING." 相似文献
7.
Previous work has shown that networks of neurons with two coupled layers of excitatory and inhibitory neurons can reveal oscillatory activity. For example, B?rgers and Kopell (2003) have shown that oscillations occur when the excitatory neurons receive a sufficiently large input. A constant drive to the excitatory neurons is sufficient for oscillatory activity. Other studies (Doiron, Chacron, Maler, Longtin, & Bastian, 2003; Doiron, Lindner, Longtin, Maler, & Bastian, 2004) have shown that networks of neurons with two coupled layers of excitatory and inhibitory neurons reveal oscillatory activity only if the excitatory neurons receive correlated input, regardless of the amount of excitatory input. In this study, we show that these apparently contradictory results can be explained by the behavior of a single model operating in different regimes of parameter space. Moreover, we show that adding dynamic synapses in the inhibitory feedback loop provides a robust network behavior over a broad range of stimulus intensities, contrary to that of previous models. A remarkable property of the introduction of dynamic synapses is that the activity of the network reveals synchronized oscillatory components in the case of correlated input, but also reflects the temporal behavior of the input signal to the excitatory neurons. This allows the network to encode both the temporal characteristics of the input and the presence of spatial correlations in the input simultaneously. 相似文献
8.
In model networks of E-cells and I-cells (excitatory and inhibitory neurons, respectively), synchronous rhythmic spiking often comes about from the interplay between the two cell groups: the E-cells synchronize the I-cells and vice versa. Under ideal conditions-homogeneity in relevant network parameters and all-to-all connectivity, for instance-this mechanism can yield perfect synchronization. We find that approximate, imperfect synchronization is possible even with very sparse, random connectivity. The crucial quantity is the expected number of inputs per cell. As long as it is large enough (more precisely, as long as the variance of the total number of synaptic inputs per cell is small enough), tight synchronization is possible. The desynchronizing effect of random connectivity can be reduced by strengthening the E --> I synapses. More surprising, it cannot be reduced by strengthening the I --> E synapses. However, the decay time constant of inhibition plays an important role. Faster decay yields tighter synchrony. In particular, in models in which the inhibitory synapses are assumed to be instantaneous, the effects of sparse, random connectivity cannot be seen. 相似文献
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10.
Content-based image retrieval (CBIR) has become one of the most active research areas in the past few years. Many visual feature representations have been explored and many systems built. In this paper, we focus on an important component of these systems - relevance feedback - and how we incorporated it into the MARS retrieval system. Relevance feedback techniques are based on an interactive retrieval approach to effectively take into account user preferences to provide an improved search experience. We present a series of coherent strategies, from single-point to multipoint and multifeature approaches that we have seamlessly integrated into our system and present experimental results to show their retrieval performance characteristics.Keywords: Image retrieval - Query refinement - Relevance feedbackMichael Ortega-Binderberger: michaelo@us.ibm.comThis work was performed while the author was a Ph.D. student at the University of Illinois at Urbana-Champaign. Correspondence to: This material is based on work supported in part by the National Science Foundation under Award Numbers CAREER IIS-9734300, 9996140, 0083489, 0331707, and 0331690 and in part by the Army Research Laboratory under Cooperative Agreement No. DAAL01-96-2-0003. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation or the Army Research Laboratory. Michael Ortega-Binderberger was supported in part by CONACYT award # 89061. 相似文献
11.
提出了一种新的基于内容的图像检索算法,该算法提取图像的颜色-空间特征,在HSV空间中将图像按照H分量进行区域划分,利用区域特征层面上的相似度对图像进行检索,并引入用户的相关反馈来调整并记录示例图像中各对象的特征权值。实验结果表明,该算法可以使计算机更加精确地理解用户的查询要求,提高查询的准确率。 相似文献
12.
鉴于单一视觉特征不能很好地表达图像内容,提出一种融合图像颜色、形状、纹理特征的图像检索方法。最后采用支持向量机(SVM)的相关反馈算法提高图像检索的准确度,缩小低层特征和高层语义之间的语义鸿沟。实验结果说明提出的方法具有良好的检索性能。 相似文献
13.
14.
Boteanu Bogdan Mironică Ionuţ Ionescu Bogdan 《Multimedia Tools and Applications》2017,76(9):11889-11916
Multimedia Tools and Applications - In this paper we introduce a novel pseudo-relevance feedback (RF) perspective to social image search results diversification. Traditional RF techniques introduce... 相似文献
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16.
Relevance feedback in image retrieval: A comprehensive review 总被引:22,自引:1,他引:22
We analyze the nature of the relevance feedback problem in a continuous representation space in the context of content-based
image retrieval. Emphasis is put on exploring the uniqueness of the problem and comparing the assumptions, implementations,
and merits of various solutions in the literature. An attempt is made to compile a list of critical issues to consider when
designing a relevance feedback algorithm. With a comprehensive review as the main portion, this paper also offers some novel
solutions and perspectives throughout the discussion.
RID="*"
ID="*" Work was done while at the University of Illinois. 相似文献
17.
TaoWang YongRui Jia-GuangSun 《计算机科学技术学报》2004,19(3):0-0
In this paper, region features and relevance feedback are used to improve the performance of CBIR. Unlike existing region-based approaches where either individual regions are used or only simple spatial layout is modeled, the proposed approach simultaneously models both region properties and their spatial relationships in a probabilistic framework. Furthermore, the retrieval performance is improved by an adaptive filter based relevance feedback. To illustrate the performance of the proposed approach, extensive experiments have been carried out on a large heterogeneous image collection with 17,000 images, which render promising results on a wide variety of queries. 相似文献
18.
In this paper, we propose CYBER, a CommunitY
Based sEaRch engine, for information retrieval utilizing community feedback information in a DHT network. In CYBER, each user is associated
with a set of user profiles that capture his/her interests. Likewise, a document is associated with a set of profiles—one
for each indexed term. A document profile is updated by users who query on the term and consider the document as a relevant
answer. Thus, the profile acts as a consolidation of users feedback from the same community, and reflects their interests.
In this way, as one user finds a document to be relevant, another user in the same community issuing a similar query will
benefit from the feedback provided by the earlier user. Hence, the search quality in terms of both precision and recall is
improved. Moreover, we further improve the effectiveness of CYBER by introducing an index tuning technique. By choosing the
indexing terms more carefully, community-based relevance feedback is utilized in both building/refining indices and re-evaluating
queries. We first propose a naive scheme, CYBER+, which involves an index tuning technique based on past queries only, and
then re-evaluates queries in a separate step. We then propose a more complex scheme, CYBER+ +, which refines its index based
on both past queries and relevance feedback. As the index is built with more selective and accurate terms, the search performance
is further improved. We conduct a comprehensive experimental study and the results show the effectiveness of our schemes. 相似文献
19.
使用基于文本的互联网图像检索技术是互联网图像检索最实用的方式,也对其他方式的互联网图像检索有重要辅助作用,但如何利用周边文本来对图像进行准确描述一直是一个难题。利用TFIDF为基础提出了一个基于句法和文本重要性分类的图像关键词权重计算方法,并尝试通过图像的相似性因素作为反馈进一步优化搜索结果,为用户返回最贴切的搜索结果。 相似文献
20.
Rujie Yuehong Wang Takayuki Baba Daiki Masumoto Shigemi Nagata 《Pattern recognition》2008,41(8):2645-2655
In content-based image retrieval, relevance feedback is studied extensively to narrow the gap between low-level image feature and high-level semantic concept. However, most methods are challenged by small sample size problem since users are usually not so patient to label a large number of training instances in the relevance feedback round. In this paper, this problem is solved by two strategies: (1) designing a new active selection criterion to select images for user's feedback. It takes both the informative and the representative measures into consideration, thus the diversities between these images are increased while their informative powers are kept. With this new criterion, more information gain can be obtained from the feedback images; and (2) incorporating unlabeled images within the co-training framework. Unlabeled data partially alleviates the training data scarcity problem, thus improves the efficiency of support vector machine (SVM) active learning. Systematic experimental results verify the superiority of our method over existing active learning methods. 相似文献