Random forests (RFs) have been widely used as a powerful classification method. However, with the randomization in both bagging samples and feature selection, the trees in the forest tend to select uninformative featu...
Pseudo-relevance feedback has been perceived as an effective solution for automatic query ***,a recent study has shown that traditional pseudo-relevance feedback may bring into topic drift and hence be harmful to the ...
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Pseudo-relevance feedback has been perceived as an effective solution for automatic query ***,a recent study has shown that traditional pseudo-relevance feedback may bring into topic drift and hence be harmful to the retrieval *** this paper,using the idea of local analysis,an effective XML query expansion method,is presented,which utilizes the local word co-occurrence information in good pseudo-relevance document collection and the structural semantics of XML to select most appropriate expansion *** results on INEX 2005 IEEE-CS collection show that the proposed expansion method offers better retrieval performance,compared with original query.
With the dramatic increase of data volume, automatic data distribution has been one of the key techniques and intractable problem for distributed systems. This work summarizes the problem of data distribution and abst...
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A BP neural network has a highly nonlinear mapping ability. It has been successfully used to predict many aspects of the steel industry. This paper introduces a working principle of the BP algorithm and uses the BP ne...
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ISBN:
(纸本)9781784660529
A BP neural network has a highly nonlinear mapping ability. It has been successfully used to predict many aspects of the steel industry. This paper introduces a working principle of the BP algorithm and uses the BP network to establish a predictive model of process parameters through inputting chemical element content and mechanical properties of steel, respectively using the predictive model to predict on original data and data after clustering according to certain rules. Then to compare the prediction results of process parameters before and after clustering with actual value. A number of experiments show that using a BP neural network to predict can more accurately reflect the actual situation after clustering.
A survey about the information needs of elderly people could find out the information required to address the needs of the aged in a community. Analyzing data collected from 600 elderly people through
A survey about the information needs of elderly people could find out the information required to address the needs of the aged in a community. Analyzing data collected from 600 elderly people through
Head-driven statistical models for natural language parsing are the most representative lexicalized syntactic parsing models, but they only utilize semantic dependency between words, and do not incorporate other seman...
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Head-driven statistical models for natural language parsing are the most representative lexicalized syntactic parsing models, but they only utilize semantic dependency between words, and do not incorporate other semantic information such as semantic collocation and semantic category. Some improvements on this distinctive parser are presented. Firstly, "valency" is an essential semantic feature of words. Once the valency of word is determined, the collocation of the word is clear, and the sentence structure can be directly derived. Thus, a syntactic parsing model combining valence structure with semantic dependency is purposed on the base of head-driven statistical syntactic parsing models. Secondly, semantic role labeling(SRL) is very necessary for deep natural language processing. An integrated parsing approach is proposed to integrate semantic parsing into the syntactic parsing process. Experiments are conducted for the refined statistical parser. The results show that 87.12% precision and 85.04% recall are obtained, and F measure is improved by 5.68% compared with the head-driven parsing model introduced by Collins.
Marginal Fisher analysis (MFA) is a well-known linear dimensionality reduction method. However, MFA does not utilize the local diversity information of the training data, which will degrade its performance. In order t...
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Marginal Fisher analysis (MFA) is a well-known linear dimensionality reduction method. However, MFA does not utilize the local diversity information of the training data, which will degrade its performance. In order to enhance the discriminant power of MFA, this paper considers introducing local variation quantity to enlarge the distances between local neighborhood embeddings and proposes a flexible and efficient implementation of MFA (F-MFA) within the regularization framework. Therefore, the discriminant structure and diversity of data are preserved in low-dimensional subspace. Computationally, F-MFA is formulated as a trace differential optimization problem which can completely avoids the singularity problem as it exists in MFA. Further, an efficient algorithm is developed for implementing F-MFA via QR-decomposition. Experimental results on four face data sets demonstrate the effectiveness of our approach.
The cohesive collective motion (flocking, swarming) of autonomous agents is ubiquitously observed and exploited in both natural and man-made settings, thus, minimal models for its description are essential. In a model...
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The cohesive collective motion (flocking, swarming) of autonomous agents is ubiquitously observed and exploited in both natural and man-made settings, thus, minimal models for its description are essential. In a model with continuous space and time we find that if two particles arrive symmetrically in a plane at a large angle, then (i) radial repulsion and (ii) linear self-propelling toward a fixed preferred speed are sufficient for them to depart at a smaller angle. For this local gain of momentum explicit velocity alignment is not necessary, nor are adhesion or attraction, inelasticity or anisotropy of the particles, or nonlinear drag. With many particles obeying these microscopic rules of motion we find that their spatial confinement to a square with periodic boundaries (which is an indirect form of attraction) leads to stable macroscopic ordering. As a function of the strength of added noise we see—at finite system sizes—a critical slowing down close to the order-disorder boundary and a discontinuous transition. After varying the density of particles at constant system size and varying the size of the system with constant particle density we predict that in the infinite system size (or density) limit the hysteresis loop disappears and the transition becomes continuous. We note that animals, humans, drones, etc., tend to move asynchronously and are often more responsive to motion than positions. Thus, for them velocity-based continuous models can provide higher precision than coordinate-based models. An additional characteristic and realistic feature of the model is that convergence to the ordered state is fastest at a finite density, which is in contrast to models applying (discontinuous) explicit velocity alignments and discretized time. To summarize, we find that the investigated model can provide a minimal description of flocking.
In this paper, we describe the current situation of data integration and the feature of the traditional data integration method, we analyse the data characteristics of the hot rolling process of modern steel enterpris...
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ISBN:
(纸本)9781784660529
In this paper, we describe the current situation of data integration and the feature of the traditional data integration method, we analyse the data characteristics of the hot rolling process of modern steel enterprises, and present a new dynamic data integration method, including the dynamic integration of isomerous multi-source data, the dynamic creation of a database along with a metadata management mechanism. Combined with features of data in the hot rolling process, this method could resolve the problem of the dynamic integration of isomerous multi-source data in the hot rolling process, and offer an opportunity for further comprehensive in-depth data analysis.
Identifying influential nodes is of theoretical significance in network immunization which is one of important methods to prevent virus propagation through protecting the influential nodes in a network. Lots of method...
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Identifying influential nodes is of theoretical significance in network immunization which is one of important methods to prevent virus propagation through protecting the influential nodes in a network. Lots of methods have been proposed to find these influential nodes based on the topological characteristics of a network (e.g., degree, betweenness or K-shell). Whereas due to the diversity of network topologies, these methods are not always effective in identifying influential nodes in any benchmark networks. We combine the advantages of existing methods based on attribute ranking and propose a universal ranking method, namely MAF (Multiple Attribute Fusion), to identify influential nodes from a complex network. We compare the efficiency of our proposed method with existing immunization strategies in different types of networks. Simulation results in the interactive email model show that the immunized nodes selected by MAF can restrain virus propagation effectively.
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