Development of a feature ranking method based upon the discriminative power of features and unbiased towards classifiers is of interest. We have studied a consensus feature ranking method, based on multiple classifier...
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Development of a feature ranking method based upon the discriminative power of features and unbiased towards classifiers is of interest. We have studied a consensus feature ranking method, based on multiple classifiers, and have shown its superiority to well known statistical ranking methods. In a target environment such as a medical dataset, missing values and an unbalanced distribution of data must be taken into consideration in the ranking and evaluation phases in order to legitimately apply a feature ranking method. In a comparison study, a Performance Index (PI) is proposed that takes into account both the number of features and the number of samples involved in the classification.
A mail retrieval method based on image feature is an innovative approach by which the postal department can realize the query of mail information. The paper chooses envelope images with handwritten address characters ...
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Routine clinical myocardial perfusion (MP) PET imaging involves the use of cardiac gating only. Nonetheless, respiratory motion of the heart can considerably degrade the quality of MP images and the quantitative accur...
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Routine clinical myocardial perfusion (MP) PET imaging involves the use of cardiac gating only. Nonetheless, respiratory motion of the heart can considerably degrade the quality of MP images and the quantitative accuracy of myocardial uptake estimates. We first performed a quantitative evaluation of the degrading contributions of cardiac (C) and respiratory (R) motion, as well as non-motion factors of Rb-82 positron range, photon non-collinearity, crystal scattering and penetration. For a normal human simulated phantom, we showed that the combination of all above factors resulted in -48% underestimation of myocardial activity, while corrections for all non-motion factors resulted in 21%, 36% and 41% underestimated myocardial activities in the presence of C, R and C&R motion. This means that compensation for respiratory motion must be considered as critical towards achieving overall motion compensation and/or resolution modeling. To achieve respiratory motion compensation, we used translation motion vectors to first match respiratory-only gated images to the end-expiration reference frame. Next, for each cardiac gate, a 4D EM reconstruction algorithm was applied to the R-gated data within that cardiac phase. Three techniques were compared involving reconstructions of (a) a single R-gate only, and all R-gates (b) without and (c) with respiratory motion correction (MC). Using simulated PET data, quantitative comparisons of noise vs. bias trace-off curves indicated notable improvements for the proposed 4D respiratory MC method. Using CHO analysis as applied to the task of perfusion defect detection, ROC analysis of the three methods resulted in AUC values of 0.610±0.039, 0.645±0.038 and 0.821±0.029. The CLABROC statistical test revealed that the proposed MC technique significantly outperformed the other two methods in the task of defect detection.
Visualizing information has been one of the main subjects of study in the computer field. Representing objects with diagrams is one approach to visualizing information and its effectiveness has widely been recognized....
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Visualizing information has been one of the main subjects of study in the computer field. Representing objects with diagrams is one approach to visualizing information and its effectiveness has widely been recognized. Thus far, many graph-drawing algorithms have been proposed. Several authors have studied the problem of producing tidy drawings of binary trees - drawings that are aesthetically pleasing and of minimum width. A number of aesthetics has been proposed. We extend this problem to that of general trees in this paper and give an attribute graph grammar that corresponds to general trees. Finally, we propose an application of this grammar.
We define q-Fisher informations and show q-Cramér-Rao type inequalities that the q-Gaussian distribution with special q-variances attains the minimum value of the q-Fisher informations.
We define q-Fisher informations and show q-Cramér-Rao type inequalities that the q-Gaussian distribution with special q-variances attains the minimum value of the q-Fisher informations.
Figuring out the number of queries contained in a Japanese question sentence is necessary and an important process in question answering systems. Proposed here is a heuristics- and machine learning-based method for di...
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Figuring out the number of queries contained in a Japanese question sentence is necessary and an important process in question answering systems. Proposed here is a heuristics- and machine learning-based method for di...
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Figuring out the number of queries contained in a Japanese question sentence is necessary and an important process in question answering systems. Proposed here is a heuristics- and machine learning-based method for distinguishing between single-query question and multiple-query question, and estimating the number of queries in a Japanese question sentence. Experiments show that our method works well.
In this paper, we propose 24-ary grid graphs corresponding to rectangular solid dissections for ruled line preserving operations. We also show a data structure called H9CODE that corresponds to the 24-ary grid graphs....
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ISBN:
(纸本)9789898111678
In this paper, we propose 24-ary grid graphs corresponding to rectangular solid dissections for ruled line preserving operations. We also show a data structure called H9CODE that corresponds to the 24-ary grid graphs. Furthermore, we describe a voxel unification method in the 24-ary grid graphs and show that the 24-ary grid graphs are an effective modei to represent solid graphics.
Conversation systems can be divided into two types. Task-oriented ones and non-task-oriented ones. Most recent researches on the latter one have focused on how to make the user continue the conversation without gettin...
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Conversation systems can be divided into two types. Task-oriented ones and non-task-oriented ones. Most recent researches on the latter one have focused on how to make the user continue the conversation without getting bored or tired. Some studies propose several ways to enrich the expressive forms of words or sentences. Others make efforts on topic association. Both solutions try to preserve the conversation interesting so that the user would like to continue talking with the computer. In this paper, we talk about the significance of providing topics, and give an approach to provide and control topics for a free conversation system. Specifically, the system extracts topics from the Web according to the user’s interest automatically, and keeps the conversation going on by providing the fabricated topics to the user. Also the system constantly detects the timing when the user might have lost interests in the current topic, and then changes the topic to another one obtained from a topic website. Experiments and questionnaires show that our method works well.
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