Showing papers by "Harbin Institute of Technology published in 2005"
17 Oct 2005
TL;DR: A novel non-statistics based face representation approach, local Gabor binary pattern histogram sequence (LGBPHS), in which training procedure is unnecessary to construct the face model, so that the generalizability problem is naturally avoided.
Abstract: For years, researchers in face recognition area have been representing and recognizing faces based on subspace discriminant analysis or statistical learning. Nevertheless, these approaches are always suffering from the generalizability problem. This paper proposes a novel non-statistics based face representation approach, local Gabor binary pattern histogram sequence (LGBPHS), in which training procedure is unnecessary to construct the face model, so that the generalizability problem is naturally avoided. In this approach, a face image is modeled as a "histogram sequence" by concatenating the histograms of all the local regions of all the local Gabor magnitude binary pattern maps. For recognition, histogram intersection is used to measure the similarity of different LGBPHSs and the nearest neighborhood is exploited for final classification. Additionally, we have further proposed to assign different weights for each histogram piece when measuring two LGBPHSes. Our experimental results on AR and FERET face database show the validity of the proposed approach especially for partially occluded face images, and more impressively, we have achieved the best result on FERET face database.
1,093 citations
TL;DR: A new criterion for testing the robust stability of Markovian jump linear systems with uncertain switching probabilities is established in terms of linear matrix inequalities, and a sufficient condition is proposed for the design of robust state-feedback controllers.
524 citations
TL;DR: It is argued that anodic property not only affects the reaction kinetics of various steps of EC organic oxidation, but also alters the pathway of phenol electrolysis.
510 citations
TL;DR: In this paper, the effect of nanometer Al2O3 particles concentration in the polymer dope on the permeation properties, membrane structures and antifouling performances of organic-inorganic composite membranes was examined.
369 citations
TL;DR: A novel coarse-to-fine algorithm that is able to locate text lines even under complex background is proposed and Experimental results show that this approach can fast and robustly detect text lines under various conditions.
335 citations
TL;DR: This paper revisits the problem of mixed H/sub 2//H/sub /spl infin// filtering for polytopic discrete-time systems and makes full use of the parameter-dependent stability idea, which results in a much less conservative filter design method.
Abstract: This paper revisits the problem of mixed H/sub 2//H/sub /spl infin// filtering for polytopic discrete-time systems. Differing from previous results in the quadratic framework, the filter design makes full use of the parameter-dependent stability idea: Not only is the filter dependent of the parameters (which are assumed to reside in a polytope and be measurable online), but in addition, the Lyapunov matrices are different for the entire polytope domain, as well as for different channels with respect to the mixed performances. These ideas are realized by introducing additional slack variables to the well-established performance conditions and by employing new bounding techniques, which results in a much less conservative filter design method. A numerical example is presented to illustrate the effectiveness and advantage of the developed filter design method.
322 citations
TL;DR: In this paper, the influence of applied current densities, concentration and constituents of the electrolyte as well as treatment time on micro-arc oxidization process was investigated, respectively; surface morphology and phase structure were analyzed using scanning electron microscope (SEM) and X-ray powder diffraction (XRD).
273 citations
TL;DR: In this paper, a new approach to vibration reduction of flexible spacecraft during attitude maneuver by using the theory of variable structure control (VSC) to design switching logic for thruster firing and lead zirconate titanate (PZT) as sensor and actuator for active vibration suppression is presented.
250 citations
TL;DR: The optical nonlinear absorption of the aqueous solution of platinum nanospheres protected by poly (N -vinyl-2-pyrrolidone) was investigated using open aperture Z-scan method with nanosecond pulse laser at the wavelength of 532 nm.
242 citations
TL;DR: A new edge detection approach combining Zernike moments operator with Sobel operator is proposed, which demonstrates the advantage of high precision in subpixel as Zernikes moments operator and short run time 79% more efficient than Zernke moments operator.
238 citations
TL;DR: In this article, an agent-based framework for construction supply chain coordination is designed based on the agent technology and multiattribute negotiation and multattribute utility theory (MAUT) for construction.
TL;DR: It was found that in MnO(x)/GAC catalytic ozonation, the degradation efficiency of nitrobenzene was higher under low pH conditions than under high pH conditions, and higher pH condition favored ozone decomposition.
TL;DR: In this article, a delay-differential equation was used to model a bidirectional associative memory (BAM) neural network with three neurons and its dynamics were studied in terms of local analysis and Hopf bifurcation analysis.
TL;DR: In this article, the friction stir welding of AZ31Mg/1060Al was investigated and the welds were formed when the stirring pin was off the centerline to AZ31 or to 1060, and were characterized by intercalation lamellae.
TL;DR: This paper presents a novel multipurpose digital image watermarking method based on the multistage vector quantizer structure, which can be applied to image authentication and copyright protection.
Abstract: The rapid growth of digital multimedia and Internet technologies has made copyright protection, copy protection, and integrity verification three important issues in the digital world. To solve these problems, the digital watermarking technique has been presented and widely researched. Traditional watermarking algorithms are mostly based on discrete transform domains, such as the discrete cosine transform, discrete Fourier transform (DFT), and discrete wavelet transform (DWT). Most of these algorithms are good for only one purpose. Recently, some multipurpose digital watermarking methods have been presented, which can achieve the goal of content authentication and copyright protection simultaneously. However, they are based on DWT or DFT. Lately, several robust watermarking schemes based on vector quantization (VQ) have been presented, but they can only be used for copyright protection. In this paper, we present a novel multipurpose digital image watermarking method based on the multistage vector quantizer structure, which can be applied to image authentication and copyright protection. In the proposed method, the semi-fragile watermark and the robust watermark are embedded in different VQ stages using different techniques, and both of them can be extracted without the original image. Simulation results demonstrate the effectiveness of our algorithm in terms of robustness and fragility.
TL;DR: In this article, the influence of the welding structure and the mechanical properties has been investigated and four different stir pins, two column pin and taper pin and the other two are the same size but with screw thread, were used to carry out a welding process.
TL;DR: A new method to detect outliers by discovering frequent patterns (or frequent itemsets) from the data set by defining a measure called FPOF (Frequent Pattern Outlier Factor) and proposing the FindFPOF algorithm to discover outliers.
Abstract: An outlier in a dataset is an observation or a point that is considerably dissimilar to or inconsistent with the remainder of the data. Detection of such outliers is important for many applications and has recently attracted much attention in the data mining research community. In this paper, we present a new method to detect outliers by discovering frequent patterns (or frequent itemsets) from the data set. The outliers are defined as the data transactions that contain less frequent patterns in their itemsets. We define a measure called FPOF (Frequent Pattern Outlier Factor) to detect the outlier transactions and propose the FindFPOF algorithm to discover outliers. The experimental results have shown that our approach outperformed the existing methods on identifying interesting outliers.
TL;DR: A set of criteria are suggested for the design of gene-specific and group-specific oligonucleotide probes, and the experimentally established criteria should provide valuable information for new software and algorithms for microarray-based studies.
Abstract: Criteria for the design of gene-specific and group-specific oligonucleotide probes were established experimentally via an oligonucleotide array that contained perfect match (PM) and mismatch probes (50-mers and 70-mers) based upon four genes. The effects of probe-target identity, continuous stretch, mismatch position, and hybridization free energy on specificity were tested. Little hybridization was observed at a probe-target identity of ≤85% for both 50-mer and 70-mer probes. PM signal intensities (33 to 48%) were detected at a probe-target identity of 94% for 50-mer oligonucleotides and 43 to 55% for 70-mer probes at a probe-target identity of 96%. When the effects of sequence identity and continuous stretch were considered independently, a stretch probe (>15 bases) contributed an additional 9% of the PM signal intensity compared to a nonstretch probe (≤15 bases) at the same identity level. Cross-hybridization increased as the length of continuous stretch increased. A 35-base stretch for 50-mer probes or a 50-base stretch for 70-mer probes had approximately 55% of the PM signal. Little cross-hybridization was observed for probes with a minimal binding free energy greater than −30 kcal/mol for 50-mer probes or −40 kcal/mol for 70-mer probes. Based on the experimental results, a set of criteria are suggested for the design of gene-specific and group-specific oligonucleotide probes, and the experimentally established criteria should provide valuable information for new software and algorithms for microarray-based studies.
TL;DR: In this paper, the authors consider a delayed predator-prey system and derive explicit formulas to determine the stability and the direction of periodic solutions bifurcating from Hopf bifurlcations, using normal form theory and center manifold argument.
TL;DR: It is shown that the derived estimator involves solving l+1 different standard Kalman filtering with the same dimension as the original system, so the linear minimum variance estimation for discrete-time systems with instantaneous and l-time delayed measurements is shown.
TL;DR: In this paper, the existence of solutions in W-0(1,p(x)) for the p(x)-Laplacian problems in the superlinear and sublinear cases was proved.
TL;DR: Benders decomposition has been successfully applied to take advantage of underlying problem structures for various optimization problems, such as restructured power systems operation and planning.
Abstract: It is apparent that power system restructuring provides a major forum for the application of decomposition techniques - including the Benders decomposition algorithm - to coordinate the optimization of various objectives among self-interested entities. It is used for solving large-scale, mixed-integer programming (MIP) problems. Benders decomposition has been successfully applied to take advantage of underlying problem structures for various optimization problems, such as restructured power systems operation and planning. This paper shows how Benders decomposition works in the power system.
15 Feb 2005-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, a tensile test was employed to evaluate the warm deformation properties of hot-rolled AZ31 Mg alloy at a temperature range of 50 −200°C and a strain rate range of 1.4 −10−1−s−1.
Abstract: Uniaxial tensile test was employed to evaluate the warm deformation properties of hot-rolled AZ31 Mg alloy at a temperature range of 50–200°C and a strain rate range of 1.4 × 10−3 s−1–1.4 × 10−1 s−1. The dynamic recrystallization (DRX) and twinning during the warm deformation were observed by optical microscopy (OM) and transmission electronic microscopy (TEM). It is shown that twinning characterized by a compound mode with differently oriented twins intersecting each other is the dominant deformation mechanism at low temperatures and initial deformation stage. The distortion energy accumulated by twinning is the reason for the occurrence of DRX.
TL;DR: Inspired by the insight that genes act as a module to carry out a highly integrated cellular function, this modular approach is demonstrated to be a powerful alternative approach to analyzing high dimension micro array data and is robust to high measurement noise and intrinsic biological variance inherent in microarray data.
Abstract: Development of robust and efficient methods for analyzing and interpreting high dimension gene expression profiles continues to be a focus in computational biology. The accumulated experiment evidence supports the assumption that genes express and perform their functions in modular fashions in cells. Therefore, there is an open space for development of the timely and relevant computational algorithms that use robust functional expression profiles towards precise classification of complex human diseases at the modular level. Inspired by the insight that genes act as a module to carry out a highly integrated cellular function, we thus define a low dimension functional expression profile for data reduction. After annotating each individual gene to functional categories defined in a proper gene function classification system such as Gene Ontology applied in this study, we identify those functional categories enriched with differentially expressed genes. For each functional category or functional module, we compute a summary measure (s) for the raw expression values of the annotated genes to capture the overall activity level of the module. In this way, we can treat the gene expressions within a functional module as an integrative data point to replace the multiple values of individual genes. We compare the classification performance of decision trees based on functional expression profiles with the conventional gene expression profiles using four publicly available datasets, which indicates that precise classification of tumour types and improved interpretation can be achieved with the reduced functional expression profiles. This modular approach is demonstrated to be a powerful alternative approach to analyzing high dimension microarray data and is robust to high measurement noise and intrinsic biological variance inherent in microarray data. Furthermore, efficient integration with current biological knowledge has facilitated the interpretation of the underlying molecular mechanisms for complex human diseases at the modular level.
TL;DR: In this paper, a method for simultaneous compensation of the hysteresis and creep of piezoelectric actuator based on an inverse control in open-loop operation is described.
Abstract: Piezoelectric actuators are frequently used nowadays in a wide variety of positioning devices. However, a major deficiency of piezoelectric actuators is that their open-loop control accuracy is seriously limited by hysteresis and creep effects. This paper describes a method for simultaneous compensation of the hysteresis and creep of piezoelectric actuator based on an inverse control in open-loop operation. The basis of the inverse control is formed by a hysteresis mathematical model and a creep model, which can describe precisely two phenomena. The method of solving inverse models of hysteresis and creep is described detailedly. Finally, a tracking control experiment of piezoelectric actuators for a desired trajectory is performed according to the proposed method and the experimental results demonstrate that the positioning precision is noticeably improved in open-loop operation compared to the conventional open-loop control without any compensation.
TL;DR: This paper investigates the stabilizability of linear systems with closed-loop positivity by determining a necessary and sufficient condition for the existence of desired state-feedback controllers guaranteeing the resultant closed- loop system to be asymptotically stable and positive.
Abstract: This paper investigates the stabilizability of linear systems with closed-loop positivity. A necessary and sufficient condition for the existence of desired state-feedback controllers guaranteeing the resultant closed-loop system to be asymptotically stable and positive is obtained. Both continuous and discrete-time cases are considered, and all of the conditions are expressed as linear matrix inequalities which can be easily verified by using standard numerical software. Numerical examples are provided to illustrate the proposed conditions.
20 Jun 2005
TL;DR: The paper proposes a method to keep the tracker robust to background clutters by online selecting discriminative features from a large feature space by embedded into the particle filtering process with the aid of existed "background" particles.
Abstract: The paper proposes a method to keep the tracker robust to background clutters by online selecting discriminative features from a large feature space. Furthermore, the feature selection procedure is embedded into the particle filtering process with the aid of existed "background" particles. Feature values from background patches and object observations are sampled during tracking and Fisher discriminant is employed to rank the classification capacity of each feature based on sampled values. Top-ranked discriminative features are selected into the appearance model and simultaneously invalid features are removed out to adjust the object representation adaptively. The implemented tracker with online discriminative feature selection module embedded shows promising results on experimental video sequences.
TL;DR: In this article, the authors investigated the mechanisms of Al speciation and hydrolysis in geopolymer systems based on the partial charge model together with preliminary experimental validation, showing that the positive partial charge of the Al atom is always higher than that of Si atom under conditions of similar pH values, suggesting greater tendency of [Al(OH)4]− tetrahedra to attract negatively charged groups from other species.
Abstract: The mechanisms of Al speciation and hydrolysis in geopolymer systems are investigated based on the partial charge model together with preliminary experimental validation. Calculation of the partial charges of species discloses that the positive partial charge of the Al atom is always higher than that of Si atom under conditions of similar pH values, suggesting greater tendency of [Al(OH)4]− tetrahedra to attract negatively charged groups from other species. Given Al atom with four hydroxyl groups under alkaline conditions and the potential to expand its coordination number with greater ease, condensation reactions involving aluminate species appear to occur much more readily. Thus, the model essentially predicts that aluminate species promote condensations reaction owing to factors such as their partial charge and the number of hydroxyl groups, implying that the solubility of aluminate sources (i.e. metakaolin) and the distribution of [Al(OH)4]− ions have an important influence on the mechanical properties of inorganic polymers. Corresponding experimental data on aluminate dissolution obtained from progressive milling of metakaolin particles demonstrated that varying particle sizes and different degrees of aggregation of metakaolin can have an important influence on inorganic polymer properties such as setting time, microstructure and compressive strength. The results indicate that milled metakaolin powders with high specific surface area have faster setting characteristics, higher compressive strength, and possess a more homogeneous microstructure, attributable to Al availability as predicted by the partial charge model.
TL;DR: The nonlinear correlation information entropy (NCIE) is proposed for measuring the general relationship of a multivariable data set and the suitableness and correctness of the proposed concepts as non linear correlation measure are testified.