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1.
The main thrust of this paper is application of a novel data mining approach on the log of user's feedback to improve web
multimedia information retrieval performance. A user space model was constructed based on data mining, and then integrated
into the original information space model to improve the accuracy of the new information space model. It can remove clutter
and irrelevant text information and help to eliminate mismatch between the page author's expression and the user's understanding
and expectation. User space model was also utilized to discover the relationship between high-level and low-level features
for assigning weight. The authors proposed improved Bayesian algorithm for data mining. Experiment proved that the authors'
proposed algorithm was efficient.
Project (No. 20020335020) supported by Research Fund for Doctoral Program, Ministry of Education of China 相似文献
2.
Ensemble learning HMM for motion recognition and retrieval by Isomap dimension reduction 总被引：1，自引：0，他引：1
XIANG Jian WENG Jian-guang ZHUANG Yue-ting WU Fei 《浙江大学学报(A卷英文版)》2006,7(12):2063-2072
INTRODUCTION Now more and more motion capture systems are used to acquire realistic human motion data. Due to the success of the Mocap systems, realistic and highly detailed motion clips are commercially available and widely used for producing animations of human-like characters in a variety of applications, such as simu- lations, video games and animation files. Therefore an efficient motion data recognition and retrieval technique is needed to support motion data processing, such as mot… 相似文献
3.
For linear switched system with both parameter uncertainties and time delay, a delay-dependent sufficient condition for the
existence of a new robustH
∞ feedback controller was formulated in nonlinear matrix inequalities solvable by an LMI-based iterative algorithm. Compared
with the conventional state-feedback controller, the proposed controller can achieve better robust control performance since
the delayed state is utilized as additional feedback information and the parameters of the proposed controllers are changed
synchronously with the dynamical characteristic of the system. This design method was also extended to the case where only
delayed state is available for the controller. The example of balancing an inverted pendulum on a cart demonstrates the effectiveness
and applicability of the proposed design methods.
Project (No. 2002CB312200) supported by the National Basic Research Program (973) of China 相似文献
4.
Recently there has been an increasing interest in applying random walk based methods to recommender systems. We employ a Gaussian random field to model the top-N recommendation task as a semi-supervised learning problem, taking into account the degree of each node on the user-item bipartite graph, and induce an effective absorbing random walk （ARW） algorithm for the top-N recommendation task. Our random walk approach directly generates the top-N recommendations for individuals, rather than predicting the ratings of the recommendations. Experimental results on the two real data sets show that our random walk algorithm significantly outperforms the state-of-the-art random walk based personalized ranking algorithm as well as the popular item-based collaborative filtering method. 相似文献
5.
In an object-based storage system, a novel scheme named EAP （extending attributes page） is presented to enhance the metadata reliability of the system by adding the user object file information attributes page for each user object and storing the file-related attributes of each user object in object-based storage devices. The EAP scheme requires no additional hardware equipments compared to a general method which uses backup metadata servers to improve the metadata reliability. Leveraging a Markov chain, this paper compares the metadata reliability of the system using the EAP scheme with that using only metadata servers to offer the file metadata service. Our results demonstrate that the EAP scheme can dramatically enhance the reliability of storage system metadata. 相似文献
6.
Texture classification based on EMD and FFT 总被引：2，自引：0，他引：2
XIONG Chang-zhen XU Jun-yi ZOU Jian-cheng QI Dong-xu 《浙江大学学报(A卷英文版)》2006,7(9):1516-1521
INTRODUCTION Multi-scale is one of the main features of natural images, a series of methods for representing the quality of images are presented, such as multi-scale technique based on diffusion equation (Perona and Malik, 1990), image pyramid (Burt and Adelson, 1983) and wavelet (Mallat, 1989). Bidimensional empirical mode decomposition (BEMD) (Nunes et al., 2005; Linderhed, 2004) is a new multi-scale analysis method proposed recently. The difference between BEMD and traditional mul… 相似文献
7.
A new algorithm is presented that generates developable Bézier surfaces through a Bézier curve called a directrix. The algorithm
is based on differential geometry theory on necessary and sufficient conditions for a surface which is developable, and on
degree evaluation formula for parameter curves and linear independence for Bernstein basis. No nonlinear characteristic equations
have to be solved. Moreover the vertex for a cone and the edge of regression for a tangent surface can be obtained easily.
Aumann’s algorithm for developable surfaces is a special case of this paper.
Project supported by the National Basic Research Program (973) of China (No. 2004CB719400), the National Natural Science Foundation
of China (Nos. 60373033 and 60333010) and the National Natural Science Foundation for Innovative Research Groups (No. 60021201),
China 相似文献
8.
ZOU Wan-hong DING Zhan YE Xiu-zi CHEN Zhi-yang 《浙江大学学报(A卷英文版)》2007,8(10):1633-1641
With the rapid development of 3D digital photography and 3D digital scanning devices, massive amount of point samples can be generated in acquisition of complex, real-world objects, and thus create an urgent need for advanced point-based processing and editing. In this paper, we present an interactive method for blending point-based geometries by dragging-and- dropping one point-based model onto another model’s surface metaphor. We first calculate a blending region based on the polygon of interest when the user drags-and-drops the model. Radial basis function is used to construct an implicit surface which smoothly interpolates with the transition regions. Continuing the drag-and-drop operation will make the system recalculate the blending regions and reconstruct the transition regions. The drag-and-drop operation can be compound in a constructive solid geometry (CSG) manner to interactively construct a complex point-based model from multiple simple ones. Experimental results showed that our method generates good quality transition regions between two raw point clouds and can effectively reduce the rate of overlapping during the blending. 相似文献
9.
HUANG Wen-liang LI Shi-jian LIU Duo 《浙江大学学报(A卷英文版)》2007,8(12):1971-1982
Localization is one of the substantial issues in wireless sensor networks. The key problem for the mobile beacon localization is how to choose the appropriate beacon trajectory. However, little research has been done on it. In this paper, firstly, we deduce the number of positions for a beacon to send a packet according to the acreage of ROI （region of interest）; and next we present a novel method based on virtual force to arrange the positions in arbitrary ROI; then we apply TSP （travelling salesman problem） algorithm to the positions sequence to obtain the optimal touring path, i.e. the reduced beacon trajectory. When a mobile beacon moves along the touring path, sending RF signals at every position, the sensors in ROI can work out their position with trilateration. Experimental results demonstrate that the localization method, based on the beacon reduced path, is efficient and has flexible accuracy. 相似文献
10.
WANG Chi-yu ZOU Jun FU Xin YANG Hua-yong 《浙江大学学报(A卷英文版)》2007,8(9):1422-1428
The characteristics of the fluidic flowmeter,which is a combination of impinged concave wall and bistable fluid amplifier,is investigated by experimental studies and numerical simulations. The numerical approaches are utilized to examine the time dependent flow field and pressure field inside the proposed flowmeter. The effect of varying structural parameters on flow characteristics of the proposed fluidic flowmeter is investigated by computational simulations for the optimization. Both the simulation and experimental results disclose that the hydrodynamic vibration,with the same intensity,frequency and 180° phase shift,occurs at axisymmetric points in the feedback channel of the fluidic flowmeter. Using the structural combination of impinged concave wall and bistable fluid amplifier and differential signal processing technique,a novel fluidic flowmeter with excellent immunity and improved sensibility is developed. 相似文献
11.
A method for computing the visible regions of free-form surfaces is proposed in this paper. Our work is focused on accurately
calculating the visible regions of the sequenced rational Bézier surfaces forming a solid model and having coincident edges
but no inner-intersection among them. The proposed method calculates the silhouettes of the surfaces without tessellating
them into triangle meshes commonly used in previous methods so that arbitrary precision can be obtained. The computed silhouettes
of visible surfaces are projected onto a plane orthogonal to the parallel light. Then their spatial relationship is applied
to calculate the boundaries of mutual-occlusion regions. As the connectivity of the surfaces on the solid model is taken into
account, a surface clustering technique is also employed and the mutual-occlusion calculation is accelerated. Experimental
results showed that our method is efficient and robust, and can also handle complex shapes with arbitrary precision.
Project supported by the National Basic Research Program (973) of China (No. 2002CB312106) and the National Natural Science
Foundation of China (Nos. 60533070, and 60403047). The third author was supported by the project sponsored by a Foundation
for the Author of National Excellent Doctoral Dissertation of China (No. 200342) and a Program for New Century Excellent Talents
in University (No. NCET-04-0088), China 相似文献
12.
The choice of self-concordant functions is the key to efficient algorithms for linear and quadratic convex optimizations,
which provide a method with polynomial-time iterations to solve linear and quadratic convex optimization problems. The parameters
of a self-concordant barrier function can be used to compute the complexity bound of the proposed algorithm. In this paper,
it is proved that the finite barrier function is a local self-concordant barrier function. By deriving the local values of
parameters of this barrier function, the desired complexity bound of an interior-point algorithm based on this local self-concordant
function for linear optimization problem is obtained. The bound matches the best known bound for small-update methods.
Project supported by the National Natural Science Foundation of China (Grant No.10771133), the Shanghai Leading Academic Discipline
Project (Grant No.S30101), and the Research Foundation for the Doctoral Program of Higher Education (Grant No.200802800010) 相似文献
13.
Particle swarm optimization （PSO） is an efficient, robust and simple optimization algorithm. Most studies are mainly concentrated on better understanding of the standard PSO control parameters, such as acceleration coefficients, etc. In this paper, a more simple strategy of PSO algorithm called θ-PSO is proposed. In θ-PSO, an increment of phase angle vector replaces the increment of velocity vector and the positions are decided by the mapping of phase angles. Benchmark testing of nonlinear functions is described and the results show that the performance of θ-PSO is much more effective than that of the standard PSO. 相似文献
14.
In this paper, a G1, C1, C2 PH-spline is employed as an approximation for a give Bézier curve within error bound and further renders offset which can
be regarded as an approximate offset to the Bézier curve. The errors between PH-spline and the Bézier curve, the offset to
PH-spline and the offset to the given Bézier curve are also estimated. A new algorithm for constructing offset to the Bézier
curve is proposed.
Project supported by the National Natural Foundation of China (No. 60073023) and the National Basic Research Program (973)
of China (No. 2002CB312101) 相似文献
15.
Understanding visual-auditory correlation from heterogeneous features for cross-media retrieval 总被引：1，自引：0，他引：1
Cross-media retrieval is an interesting research topic, which seeks to remove the barriers among different modalities. To enable cross-media retrieval, it is needed to find the correlation measures between heterogeneous low-level features and to judge the semantic similarity. This paper presents a novel approach to learn cross-media correlation between visual features and auditory features for image-audio retrieval. A semi-supervised correlation preserving mapping （SSCPM） method is described to construct the isomorphic SSCPM subspace where canonical correlations between the original visual and auditory features are further preserved. Subspace optimization algorithm is proposed to improve the local image cluster and audio cluster quality in an interactive way. A unique relevance feedback strategy is developed to update the knowledge of cross-media correlation by learning from user behaviors, so retrieval performance is enhanced in a progressive manner. Experimental results show that the performance of our approach is effective. 相似文献
16.
Construction simulation and real-time control for high arch dam 总被引：1，自引：0，他引：1
A method of combining dynamic simulation with real-time control was proposed to fit the randomness and uncertainty in the
high arch dam construction process. The mathematical logic model of high arch dam construction process was established. By
combining dynamic construction simulation with schedule analysis, the process of construction schedule forecasting and analysis
based on dynamic simulation was studied. The process of real-time schedule control was constructed and some measures for dynamic
adjustment and control of construction schedule were provided. A system developed with the method is utilized in a being constructed
hydroelectric project located at the Yellow River in northwest China, which can make the pouring plan of the dam in the next
stage (a month, quarter or year) to guide the practical construction. The application result shows that the system provides
an effective technical support for the construction and management of the dam.
ZHONG Denghua, born in 1963, male, Dr, Prof.
Supported by National Natural Science Foundation of China(No.50539120), National Basic Research Program of China(“973”Program,No.
2007 CB714101), National Science Fund for Distinguished Young Scholars of China(No.50525927), and National Natural Science
Foundation of China (No.50579045). 相似文献
17.
Jia-ying Zhu Gong-yin Ye Qi Fang Cui Hu 《Journal of Zhejiang University. Science. B》2009,10(6):445-453
Although the biochemical dissection of parasitoid-host interactions is becoming well characterized, the molecular knowledge
concerning them is minimal. In order to understand the molecular bases of the host immune response to parasitoid attack, we
explored the response of Papilio xuthus parasitized by the endoparasitic wasp Pteromalus puparum using proteomic approach. By examining the differential expression of plasma proteins in the parasitized and unparasitized
host pupae by two-dimensional (2D) electrophoresis, 16 proteins were found to vary in relation to parasitization compared
with unparasitized control samples. All of them were submitted to identification by mass spectrometry coupled with a database
search. The modulated proteins were found to fall into the following functional groups: humoral or cellular immunity, detoxification,
energy metabolism, and others. This study contributes insights into the molecular mechanism of the relationships between parasitoids
and their host insects.
Project supported by the National Basic Research Program (973) of China (No. 2006CB102005), the National Natural Science Foundation
of China (Nos. 30571251 and 30170626), the Program for New Century Excellent Talents in University of the Ministry of Education
of China (No. NCET-05-0513), and the Innovation Research Team Program of the Ministry of Education of China (No. IRT0535) 相似文献
18.
CAI Ke-ke BU Jia-jun CHEN Chun QIU Guang 《浙江大学学报(A卷英文版)》2007,8(6):871-882
This paper explores the application of term dependency in information retrieval (IR) and proposes a novel dependency retrieval model. This retrieval model suggests an extension to the existing language modeling (LM) approach to IR by introducing dependency models for both query and document. Relevance between document and query is then evaluated by reference to the Kullback-Leibler divergence between their dependency models. This paper introduces a novel hybrid dependency structure, which allows integration of various forms of dependency within a single framework. A pseudo relevance feedback based method is also introduced for constructing query dependency model. The basic idea is to use query-relevant top-ranking sentences extracted from the top documents at retrieval time as the augmented representation of query, from which the relationships between query terms are identified. A Markov Random Field (MRF) based approach is presented to ensure the relevance of the extracted sentences, which utilizes the association features between query terms within a sentence to evaluate the relevance of each sentence. This dependency retrieval model was compared with other traditional retrieval models. Experiments indicated that it produces significant improvements in retrieval effectiveness. 相似文献
19.
This paper explores brain CT slices segmentation technique and some related problems, including contours segmentation algorithms,
edge detector, algorithm evaluation and experimental results. This article describes a method for contour-based segmentation
of anatomical structures in 3D medical data sets. With this method, the user manually traces one or more 2D contours of an
anatomical structure of interest on parallel planes arbitrarily cutting the data set. The experimental results showed the
segmentation based on 3D brain volume and 2D CT slices. The main creative contributions in this paper are: (1) contours segmentation
algorithm; (2) edge detector; (3) algorithm evaluation.
Project (No.69931010) supported by the National Natural Science Foundation of China 相似文献
20.
The new genetic algorithm for training layered feedforward neural networks proposed here uses a mutation operator for performing
the search behaviors of local optimization. Combining the random restart method with the local search technique, the algorithm
can converge asymptocally, to the optimal solution. Test with a practical example showed that the improved genetic algorthm
is more efficient than the conventional genetic algorithm.
Project supported by NSFC (No 39870940) and (G199054405-973) the National Key Scientific Research & Development Program. 相似文献