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排序方式: 共有2363条查询结果,搜索用时 31 毫秒
31.
This paper presents a wavelet-based kernel Principal Component Analysis (PCA) method by integrating the Daubechies wavelet representation of palm images and the kernel PCA method for palmprint recognition. Kernel PCA is a technique for nonlinear dimension reduction of data with an underlying nonlinear spatial structure. The intensity values of the palmprint image are first normalized by using mean and standard deviation. The palmprint is then transformed into the wavelet domain to decompose palm images and the lowest resolution subband coeffcients are chosen for palm representation. The kernel PCA method is then applied to extract non-linear features from the subband coeffcients. Finally, similarity measurement is accomplished by using weighted Euclidean linear distance-based nearest neighbor classifier. Experimental results on PolyU Palmprint Databases demonstrate that the proposed approach achieves highly competitive performance with respect to the published palmprint recognition approaches. 相似文献
32.
33.
The wavelet domain association rules method is proposed for efficient texture characterization. The concept of association rules to capture the frequently occurring local intensity variation in textures. The frequency of occurrence of these local patterns within a region is used as texture features. Since texture is basically a multi-scale phenomenon, multi-resolution approaches such as wavelets, are expected to perform efficiently for texture analysis. Thus, this study proposes a new algorithm which uses the wavelet domain association rules for texture classification. Essentially, this work is an extension version of an early work of the Rushing et al. [10], [11], where the generation of intensity domain association rules generation was proposed for efficient texture characterization. The wavelet domain and the intensity domain (gray scale) association rules were generated for performance comparison purposes. As a result, Rushing et al. [10], [11] demonstrated that intensity domain association rules performs much more accurate results than those of the methods which were compared in the Rushing et al. work. Moreover, the performed experimental studies showed the effectiveness of the wavelet domain association rules than the intensity domain association rules for texture classification problem. The overall success rate is about 97%. 相似文献
34.
Can an electronic portfolio that is both a multimedia container for student work and a tool to support key learning processes have a positive impact on the literacy practices and self-regulated learning skills of students? This article presents the findings of a yearlong study conducted in three Canadian provinces during the 2007–2008 school year initially involving 32 teachers and 388 students. Due to varying levels of implementation our final data set included 14 teachers and 296 students. Using a non-equivalent pre-test/post-test design, we found that grade 4–6 students who were in classrooms where the teacher provided regular and appropriate use of the electronic portfolio tool ePEARL (i.e., medium–high implementation condition, n = 7 classrooms and 121 students), compared to control students (n = 7 classrooms and 175 students) who did not use ePEARL, showed significant improvements (p < .05) in their writing skills on a standardized literacy measure (i.e., the constructed response subtest of the Canadian Achievement Test-4th ed.) and certain metacognitive skills measured via student self-report. The results of this study indicate that teaching with ePEARL has positive impacts on students’ literacy and self-regulated learning skills when the tool is used regularly and integrated into classroom instruction. 相似文献
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36.
Due to a lot of robot manipulators application in industry, low noise degree is very important criteria for robot manipulator's joints. In this paper, joint noise problem of a robot manipulator with five joints is investigated both theoretically and experimentally. The investigation is consisted of two steps. First step is to analyze the noise of joints using a hardware and software. The hardware is a part of noise sensors. The second step; according to experimental results, some neural networks are employed for finding robust neural noise analyzer. Five types of neural networks are used to compare each other. From the results, it is noted that the proposed RBFNN gives the best results for analyzing joint noise of the robot manipulator. 相似文献
37.
Mathematical model of vertical electrical sounding by using resistivity method is studied. The model leads to an inverse problem of determination of the unknown leading coefficient (conductivity) of the elliptic equation in R2 in a slab. The direct problem is obtained in the form of mixed BVP in axisymmetric cylindrical coordinates. The additional (available measured) data is given on the upper boundary of the slab, in the form of tangential derivative. Due to ill-conditionedness of the considered inverse problem the logarithmic transformation is applied to the unknown coefficient and the inverse problem is studied as a minimization problem for the cost functional, with respect to the reflection coefficient. The Conjugate Gradient method (CGM) is applied for the numerical solution of this problem. Computational experiments were performed with noise free and random noisy data. 相似文献
38.
Recognizing people by gait promises to be useful for identifying individuals from a distance; in this regard, improved techniques
are under development. In this paper, an improved method for gait recognition is proposed. Binarized silhouette of a motion
object is first represented by four 1-D signals that are the basic image features called the distance vectors. The distance
vectors are differences between the bounding box and silhouette, and extracted using four projections to silhouette. Fourier
Transform is employed as a preprocessing step to achieve translation invariant for the gait patterns accumulated from silhouette
sequences that are extracted from the subjects’ walk in different speed and/or different time. Then, eigenspace transformation
is applied to reduce the dimensionality of the input feature space. Support vector machine (SVM)-based pattern classification
technique is then performed in the lower-dimensional eigenspace for recognition. The input feature space is alternatively
constructed by using two different approaches. The four projections (1-D signals) are independently classified in the first
approach. A fusion task is then applied to produce the final decision. In the second approach, the four projections are concatenated
to have one vector and then pattern classification with one vector is performed in the lower-dimensional eigenspace for recognition.
The experiments are carried out on the most well-known public gait databases: the CMU, the USF, SOTON, and NLPR human gait
databases. To effectively understand the performance of the algorithm, the experiments are executed and presented as increasing
amounts of the gait cycles of each person available during the training procedure. Finally, the performance of the proposed
algorithm is comparatively illustrated to take into consideration the published gait recognition approaches. 相似文献
39.
Multiobjective evolutionary clustering of Web user sessions: a case study in Web page recommendation
G. Nildem Demir A. Şima Uyar Şule Gündüz-Öğüdücü 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2010,14(6):579-597
In this study, we experiment with several multiobjective evolutionary algorithms to determine a suitable approach for clustering
Web user sessions, which consist of sequences of Web pages visited by the users. Our experimental results show that the multiobjective
evolutionary algorithm-based approaches are successful for sequence clustering. We look at a commonly used cluster validity
index to verify our findings. The results for this index indicate that the clustering solutions are of high quality. As a
case study, the obtained clusters are then used in a Web recommender system for representing usage patterns. As a result of
the experiments, we see that these approaches can successfully be applied for generating clustering solutions that lead to
a high recommendation accuracy in the recommender model we used in this paper. 相似文献
40.
Dan Selişteanu Monica Roman Dorin Şendrescu 《Simulation Modelling Practice and Theory》2010,18(9):1297-1313
This paper deals with the problem of modelling and on-line estimation of kinetics for a biomethanation process. This bioprocess is in fact a wastewater biodegradation process with production of methane gas, which takes place inside a Continuous Stirred Tank Bioreactor. The reaction scheme and the analysis of biochemical phenomena inside the bioreactor are used in order to obtain a nonlinear dynamic model of the bioprocess, by means of the pseudo Bond Graph method. Two nonlinear estimation strategies are developed for the identification of unknown kinetics of the bioprocess. First, an estimator is developed by using a state observer based technique. Second, an observer based on high-gain approach is designed and implemented. Several numerical simulations are performed in order to analyse and compare the behaviour and the performance of the proposed estimators. 相似文献