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981.
A Regression Approach to Music Emotion Recognition   总被引:3,自引:0,他引:3  
Content-based retrieval has emerged in the face of content explosion as a promising approach to information access. In this paper, we focus on the challenging issue of recognizing the emotion content of music signals, or music emotion recognition (MER). Specifically, we formulate MER as a regression problem to predict the arousal and valence values (AV values) of each music sample directly. Associated with the AV values, each music sample becomes a point in the arousal-valence plane, so the users can efficiently retrieve the music sample by specifying a desired point in the emotion plane. Because no categorical taxonomy is used, the regression approach is free of the ambiguity inherent to conventional categorical approaches. To improve the performance, we apply principal component analysis to reduce the correlation between arousal and valence, and RReliefF to select important features. An extensive performance study is conducted to evaluate the accuracy of the regression approach for predicting AV values. The best performance evaluated in terms of the R 2 statistics reaches 58.3% for arousal and 28.1% for valence by employing support vector machine as the regressor. We also apply the regression approach to detect the emotion variation within a music selection and find the prediction accuracy superior to existing works. A group-wise MER scheme is also developed to address the subjectivity issue of emotion perception.  相似文献   
982.
Partial cognates are pairs of words in two languages that have the same meaning in some, but not all contexts. Detecting the actual meaning of a partial cognate in context can be useful for Machine Translation tools and for Computer-Assisted Language Learning tools. We propose a supervised and a semi-supervised method to disambiguate partial cognates between two languages: French and English. The methods use only automatically-labeled data; therefore they can be applied to other pairs of languages as well. The aim of our work is to automatically detect the meaning of a French partial cognate word in a specific context.
Diana InkpenEmail:
  相似文献   
983.
Certified email is a system which enables a sender to prove a receiver’s receipt of email. Such a system can be used for applications related to electronic commerce on the Internet. This paper considers a situation where a sender or a receiver wants to change his/her mind due to the change of mail content value (e.g., stock, auction, gambling) during the transaction. We point out that no traditional certified email systems have been designed for such a case, thus one of the participants can be at a disadvantage. To avoid this problem, we propose an evenhanded certified email system in which each participant can change his/her choice, either cancel or finish the transaction, at any time during the transaction.
Kouichi SakuraiEmail:
  相似文献   
984.
我试图通过解读修辞学的发展历程,探究符号学发展的必然性,由本不存在修辞,到需要修辞,再到修辞的消亡的逻辑关系,联想到设计符号学的发展历程竟与其如此惊人的相似,由仅追求原始功能,到添加装饰满足非本质的需求,继而又摒弃装饰成分,聚焦其本质所在的现代设计,就像我在文章开头说的乙杂邢薜姆绞奖硐治尴蘧褪敲烙是象征的精髓一样,以最简洁的形式传达了最准确的信息,是设计符号学的核心所在。  相似文献   
985.
The aim of this paper is to extend the probabilistic choice in probabilistic programs to sub-probabilistic choice, i.e., of the form (p)P (q)Q where p + q ⩽ 1. It means that program P is executed with probability p and program Q is executed with probability q. Then, starting from an initial state, the execution of a sub-probabilistic program results in a sub-probability distribution. This paper presents two equivalent semantics for a sub-probabilistic while-programming language. One of these interprets programs as sub-probabilistic distributions on state spaces via denotational semantics. The other interprets programs as bounded expectation transformers via wp-semantics. This paper proposes an axiomatic systems for total logic, and proves its soundness and completeness in a classical pattern on the structure of programs.  相似文献   
986.
A malware mutation engine is able to transform a malicious program to create a different version of the program. Such mutation engines are used at distribution sites or in self-propagating malware in order to create variation in the distributed programs. Program normalization is a way to remove variety introduced by mutation engines, and can thus simplify the problem of detecting variant strains. This paper introduces the “normalizer construction problem” (NCP), and formalizes a restricted form of the problem called “NCP=”, which assumes a model of the engine is already known in the form of a term rewriting system. It is shown that even this restricted version of the problem is undecidable. A procedure is provided that can, in certain cases, automatically solve NCP= from the model of the engine. This procedure is analyzed in conjunction with term rewriting theory to create a list of distinct classes of normalizer construction problems. These classes yield a list of possible attack vectors. Three strategies are defined for approximate solutions of NCP=, and an analysis is provided of the risks they entail. A case study using the virus suggests the approximations may be effective in practice for countering mutated malware. R. Mathur is presently at McAfee AVERT Labs.  相似文献   
987.
The flow field of a long bubble steadily expelling a viscous fluid confined by two closely located parallel plates is examined. In order to investigate the influence of bubble size on the flow field, a theoretical bubble profile is used to replace the complicated procedure for computing simultaneously the interface between the gas surface and fluid flows. The present study showed the two typical flow patterns and also a third flow pattern of the stagnation point moving in the region of the bubble tip front during transformation of the two typical flow patterns. The vorticity patterns are also drawn for various bubble profiles and are examined for their effect on the flow. The velocity field is also presented from two different viewpoints and the phenomena is examined. The stagnation point located on the center line between the bubble tip to the upstream is only found in the small range of in a channel, where λ is ratio of the bubble width to the distance between two parallel plates.  相似文献   
988.
989.
We consider the edit distance with moves on the class of words and the class of ordered trees. We first exhibit a simple tester for the class of regular languages on words and generalize it to the class of ranked and unranked regular trees. We also show that this distance problem is -complete on ordered trees. A preliminary version of this paper appeared in Proceedings of 31st International Colloquium on Automata, Languages and Programming, volume 3142 of Lecture Notes in Computer Science, pages 932–944, Springer, 2005. Work supported by ACI Sécurité Informatique: VERA of the French Ministry of research.  相似文献   
990.
利用计算机进行设计各种字形修饰效果一直是计算机图形学的重要内容之一.本文给出了在轮廓字表面上构造网格点,基于这些网格点进行Delaunay三角剖分,并转换为3-4网格,最后在网格上实现编织带修饰效果的具体实现方法.其中3-4网格由良构的四边形单元和少量辅助三角形单元构成,在其上实现了较好的编织带修饰的效果.  相似文献   
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