Showing papers by "Harbin Institute of Technology published in 2010"
TL;DR: A possible way to fabricate graphene oxide/semiconductor composites with different properties by using a tunable semiconductor conductivity type of graphene oxide is shown.
Abstract: Graphene oxide/TiO2 composites were prepared by using TiCl3 and graphene oxide as reactants. The concentration of graphene oxide in starting solution played an important role in photoelectronic and photocatalytic performance of graphene oxide/TiO2 composites. Either a p-type or n-type semiconductor was formed by graphene oxide in graphene oxide/TiO2 composites. These semiconductors could be excited by visible light with wavelengths longer than 510 nm and acted as sensitizer in graphene oxide/TiO2 composites. Visible-light driven photocatalytic performance of graphene oxide/TiO2 composites in degradation of methyl orange was also studied. Crystalline quality and chemical states of carbon elements from graphene oxide in graphene oxide/TiO2 composites depended on the concentration of graphene oxide in the starting solution. This study shows a possible way to fabricate graphene oxide/semiconductor composites with different properties by using a tunable semiconductor conductivity type of graphene oxide.
820 citations
TL;DR: In this article, the adsorption isotherms at different temperatures were determined and modeled with Langmuir, Freundlich and Redlich-Peterson equations, and the effects of solution pH on the adorption were also studied.
787 citations
TL;DR: By allowing the Lyapunov-like function to increase during the running time of active subsystems, the extended stability results for switched systems with ADT in nonlinear setting are derived and the asynchronously switched stabilizing control problem for linear cases is solved.
682 citations
TL;DR: The authors found that consumer-generated ratings about the quality of food, environment and service of restaurants, and the volume of online consumer reviews are positively associated with the online popularity of restaurants; whereas editor reviews have a negative relationship with consumers' intention to visit a restaurant's webpage.
662 citations
TL;DR: A new necessary and sufficient condition is proposed in terms of strict linear matrix inequality (LMI), which guarantees the stochastic admissibility of the unforced Markovian jump singular system.
Abstract: This paper is concerned with the state estimation and sliding-mode control problems for continuous-time Markovian jump singular systems with unmeasured states. Firstly, a new necessary and sufficient condition is proposed in terms of strict linear matrix inequality (LMI), which guarantees the stochastic admissibility of the unforced Markovian jump singular system. Then, the sliding-mode control problem is considered by designing an integral sliding surface function. An observer is designed to estimate the system states, and a sliding-mode control scheme is synthesized for the reaching motion based on the state estimates. It is shown that the sliding mode in the estimation space can be attained in a finite time. Some conditions for the stochastic admissibility of the overall closed-loop system are derived. Finally, a numerical example is provided to illustrate the effectiveness of the proposed theory.
596 citations
TL;DR: The interactions between the vectors and DNA leading to complex formation, the supramolecular structures of lipoplexes and polyplexes, and their mechanisms of DNA transfer are reviewed to provide a framework for the future design and synthesis of optimal non-viral vectors for gene therapy.
594 citations
TL;DR: A new type of augmented Lyapunov functional is proposed which contains some triple-integral terms and some new stability criteria are derived in terms of linear matrix inequalities without introducing any free-weighting matrices.
549 citations
TL;DR: The overall results show that microaneurysm detection is a challenging task for both the automatic methods as well as the human expert, and there is room for improvement as the best performing system does not reach the performance of thehuman expert.
Abstract: The detection of microaneurysms in digital color fundus photographs is a critical first step in automated screening for diabetic retinopathy (DR), a common complication of diabetes. To accomplish this detection numerous methods have been published in the past but none of these was compared with each other on the same data. In this work we present the results of the first international microaneurysm detection competition, organized in the context of the Retinopathy Online Challenge (ROC), a multiyear online competition for various aspects of DR detection. For this competition, we compare the results of five different methods, produced by five different teams of researchers on the same set of data. The evaluation was performed in a uniform manner using an algorithm presented in this work. The set of data used for the competition consisted of 50 training images with available reference standard and 50 test images where the reference standard was withheld by the organizers (M. Niemeijer, B. van Ginneken, and M. D. AbrA?moff). The results obtained on the test data was submitted through a website after which standardized evaluation software was used to determine the performance of each of the methods. A human expert detected microaneurysms in the test set to allow comparison with the performance of the automatic methods. The overall results show that microaneurysm detection is a challenging task for both the automatic methods as well as the human expert. There is room for improvement as the best performing system does not reach the performance of the human expert. The data associated with the ROC microaneurysm detection competition will remain publicly available and the website will continue accepting submissions.
479 citations
TL;DR: By fully considering the properties of the TRMs and TPMs, and the convexity of the uncertain domains, necessary and sufficient criteria of stability and stabilization are obtained in both continuous and discrete time.
Abstract: This technical note is concerned with exploring a new approach for the analysis and synthesis for Markov jump linear systems with incomplete transition descriptions. In the study, not all the elements of the transition rate matrices (TRMs) in continuous-time domain, or transition probability matrices (TPMs) in discrete-time domain are assumed to be known. By fully considering the properties of the TRMs and TPMs, and the convexity of the uncertain domains, necessary and sufficient criteria of stability and stabilization are obtained in both continuous and discrete time. Numerical examples are used to illustrate the results.
467 citations
TL;DR: In this note, the robust output regulation problem of a multi-agent system is considered and an internal model based distributed control scheme is adopted to achieve the objectives of asymptotic tracking and disturbance rejection in an uncertain multi- agent system.
Abstract: In this note, the robust output regulation problem of a multi-agent system is considered. An internal model based distributed control scheme is adopted to achieve the objectives of asymptotic tracking and disturbance rejection in an uncertain multi-agent system where both the reference inputs and disturbances are generated by an exosystem.
450 citations
01 Feb 2010
TL;DR: An exponential H infin synchronization method for a class of uncertain master and slave neural networks with mixed time delays, where the mixed delays comprise different neutral, discrete, and distributed time delays is established.
Abstract: This paper establishes an exponential H infin synchronization method for a class of uncertain master and slave neural networks (MSNNs) with mixed time delays, where the mixed delays comprise different neutral, discrete, and distributed time delays. The polytopic and the norm-bounded uncertainties are separately taken into consideration. An appropriate discretized Lyapunov-Krasovskii functional and some free-weighting matrices are utilized to establish some delay-dependent sufficient conditions for designing delayed state-feedback control as a synchronization law in terms of linear matrix inequalities under less restrictive conditions. The controller guarantees the exponential H infin synchronization of the two coupled MSNNs regardless of their initial states. Detailed comparisons with existing results are made, and numerical simulations are carried out to demonstrate the effectiveness of the established synchronization laws.
TL;DR: Structural health monitoring (SHM) technology has been successfully applied to understand the loads, environment actions, and behaviors of a structure subjected to various actions through solving a problem as discussed by the authors.
Abstract: Structural health monitoring (SHM) technology has been successfully applied to understand the loads, environment actions, and behaviors of a structure subjected to various actions through solving a...
Proceedings Article•
23 Aug 2010TL;DR: LTP (Language Technology Platform) is an integrated Chinese processing platform which includes a suite of high performance natural language processing modules and relevant corpora that achieved good results in some relevant evaluations, such as CoNLL and SemEval.
Abstract: LTP (Language Technology Platform) is an integrated Chinese processing platform which includes a suite of high performance natural language processing (NLP) modules and relevant corpora. Especially for the syntactic and semantic parsing modules, we achieved good results in some relevant evaluations, such as CoNLL and SemEval. Based on XML internal data representation, users can easily use these modules and corpora by invoking DLL (Dynamic Link Library) or Web service APIs (Application Program Interface), and view the processing results directly by the visualization tool.
TL;DR: This paper presents an online multispectral palmprint system that could meet the requirement of real-time application and proposes a score level fusion scheme to integrate the mult ispectral information.
Abstract: Palmprint is a unique and reliable biometric characteristic with high usability. With the increasing demand of highly accurate and robust palmprint authentication system, multispectral imaging has been employed to acquire more discriminative information and increase the antispoof capability of palmprint. This paper presents an online multispectral palmprint system that could meet the requirement of real-time application. A data acquisition device is designed to capture the palmprint images under Blue, Green, Red, and near-infrared (NIR) illuminations in less than 1 s. A large multispectral palmprint database is then established to investigate the recognition performance of each spectral band. Our experimental results show that the red channel achieves the best result, whereas the Blue and Green channels have comparable performance but are slightly inferior to the NIR channel. After analyzing the extracted features from different bands, we propose a score level fusion scheme to integrate the multispectral information. The palmprint verification experiments demonstrated the superiority of multispectral fusion to each single spectrum, which results in both higher verification accuracy and antispoofing capability.
TL;DR: In this article, a microwave-induced activation process using phosphoric acid as the activating agent was used to obtain a carbon surface with a surface area of 1432 m 2 /g and a carbon yield of 48%.
TL;DR: In this article, a case study of GHG emissions in building construction in Hong Kong is presented, and the results show that 82-87% of the total emissions are from the embodied GHGs emissions of building materials, 6-8% are from transportation of building material, and 6-9% are due to the energy consumption of construction equipment.
TL;DR: Algal organic matter, including extracellular organic matter (EOM) and intracellularorganic matter (IOM), was characterized and the formation of a variety of disinfection by-products (DBPs) in chlorination and chloramination of EOM, IOM and algal cells was evaluated.
TL;DR: A network-based approach that can infer potential microRNA-disease associations and drive testable hypotheses for the experimental efforts to identify the roles of microRNAs in human diseases is presented.
Abstract: The identification of disease-related microRNAs is vital for understanding the pathogenesis of diseases at the molecular level, and is critical for designing specific molecular tools for diagnosis, treatment and prevention. Experimental identification of disease-related microRNAs poses considerable difficulties. Computational analysis of microRNA-disease associations is an important complementary means for prioritizing microRNAs for further experimental examination. Herein, we devised a computational model to infer potential microRNA-disease associations by prioritizing the entire human microRNAome for diseases of interest. We tested the model on 270 known experimentally verified microRNA-disease associations and achieved an area under the ROC curve of 75.80%. Moreover, we demonstrated that the model is applicable to diseases with which no known microRNAs are associated. The microRNAome-wide prioritization of microRNAs for 1,599 disease phenotypes is publicly released to facilitate future identification of disease-related microRNAs. We presented a network-based approach that can infer potential microRNA-disease associations and drive testable hypotheses for the experimental efforts to identify the roles of microRNAs in human diseases.
TL;DR: It is demonstrated that this photocatalyst can be easily recycled by applying an external magnetic field while maintaining their photocatalytic activity during at least eighteen cycles of use.
Abstract: Core-shell structured Fe(3)O(4)/SiO(2)/TiO(2) nanocomposites with enhanced photocatalytic activity that are capable of fast magnetic separation have been successfully synthesized by combining two steps of a sol-gel process with calcination The as-obtained core-shell structure is composed of a central magnetite core with a strong response to external fields, an interlayer of SiO(2), and an outer layer of TiO(2) nanocrystals with a tunable average size The convenient control over the size and crystallinity of the TiO(2) nanocatalysts makes it possible to achieve higher photocatalytic efficiency than that of commercial photocatalyst Degussa P25 The photocatalytic activity increases as the thickness of the TiO(2) nanocrystal shell decreases The presence of SiO(2) interlayer helps to enhance the photocatalytic efficiency of the TiO(2) nanocrystal shell as well as the chemical and thermal stability of Fe(3)O(4) core In addition, the TiO(2) nanocrystals strongly adhere to the magnetic supports through covalent bonds We demonstrate that this photocatalyst can be easily recycled by applying an external magnetic field while maintaining their photocatalytic activity during at least eighteen cycles of use
TL;DR: Based on a piecewise Lyapunov function combined with some novel convexifying techniques, the solutions to the problem of robust H∞ output-feedback control for a class of nonlinear systems under unreliable communication links are formulated in the form of linear matrix inequalities.
Abstract: This paper investigates the problem of robust H∞ output-feedback control for a class of nonlinear systems under unreliable communication links. The nonlinear plant is represented by a Takagi-Sugeno (T-S) uncertain fuzzy model, and the communication links between the plant and controller are assumed to be imperfect, i.e., data-packet dropouts occur intermittently, which is often the case in a network environment. Stochastic variables that satisfy the Bernoulli random-binary distribution are adopted to characterize the data-missing phenomenon, and the attention is focused on the design of a piecewise static-output-feedback (SOF) controller such that the closed-loop system is stochastically stable with a guaranteed H∞ performance. Based on a piecewise Lyapunov function combined with some novel convexifying techniques, the solutions to the problem are formulated in the form of linear matrix inequalities (LMIs). Finally, simulation examples are also provided to illustrate the effectiveness of the proposed approaches.
TL;DR: In this article, the authors reviewed the interconnect materials and coatings for metallic interconnects for solid oxide fuel cells (SOFCs) and compared them with other SOFC ceramic components, and found that the requirements of interconnect are the most demanding, i.e., to maintain high electrical conductivity, good stability in both reducing and oxidizing atmospheres, and close coefficient of thermal expansion (CTE) match and good compatibility with other SoFC ceramic component.
TL;DR: This brief investigates the problem of robust sampled-data H ∞ control for active vehicle suspension systems by using an input delay approach and a quarter-car model is considered.
Abstract: This brief investigates the problem of robust sampled-data H ∞ control for active vehicle suspension systems. By using an input delay approach, the active vehicle suspension system with sampling measurements is transformed into a continuous-time system with a delay in the state. The transformed system contains non-differentiable time-varying state delay and polytopic parameter uncertainties. A Lyapunov functional approach is employed to establish the H ∞ performance, and the controller design is cast into a convex optimization problem with linear matrix inequality (LMI) constraints. A quarter-car model is considered in this brief and the effectiveness of the proposed approach is illustrated by a realistic design example.
TL;DR: The present BNNSs possess the properties complementary to carbon nanosheets such as intrinsically semiconducting, high temperature stability, and high chemical inertness and may find applications in ultraviolet nanoelectronics, catalyst supports, electron field emission, and self-cleaning coatings, etc., especially those working at high temperature and in harsh environments.
Abstract: Boron nitride (BN) is a promising semiconductor with a wide band gap (∼6 eV). Here, we report the synthesis of vertically aligned BN nanosheets (BNNSs) on silicon substrates by microwave plasma chemical vapor deposition from a gas mixture of BF3−N2−H2. The size, shape, thickness, density, and alignment of the BNNSs were well-controlled by appropriately changing the growth conditions. With changing the gas flow rates of BF3 and H2 as well as their ratio, the BNNSs evolve from three-dimensional with branches to two-dimensional with smooth surface and their thickness changes from 20 to below 5 nm. The growth of the BNNSs rather than uniform granular films is attributed to the particular chemical properties of the gas system, mainly the strong etching effect of fluorine. The alignment of the BNNSs is possibly induced by the electrical field generated in plasma sheath. Strong UV light emission with a broad band ranging from 200 to 400 nm and superhydrophobicity with contact angles over 150° were obtained for t...
TL;DR: Pt-around-Au nanocomposite is synthesized using the electrostatic selfassembly method, and this catalyst shows significantly improved activity towards formic acid oxidation.
Abstract: Pt-around-Au nanocomposite is synthesized using the electrostatic selfassembly method. This catalyst shows significantly improved activity towards formic acid oxidation. The possible reason is the efficient spillover of HCOO from Au to the surrounding Pt NPs, where HCOO is further oxidized to CO2.
TL;DR: By introducing some specified matrices, a new sufficient condition is proposed in terms of strict linear matrix inequality (LMI), which guarantees the stochastic stability of the sliding mode dynamics.
TL;DR: Basalt and glass fibers were treated with sodium hydroxide and hydrochloric acid solutions respectively for different periods of time, and the mass loss ratio and the strength maintenance ratio of the fibers were examined after the treatment as discussed by the authors.
TL;DR: The results indicated that aluminum was an excellent electrode material for algae removal as compared with iron, and the ECF technology was effective for algae Removal, from both the technical and economical points of view.
TL;DR: This paper aims to design a linear full-order filter such that the estimation error converges to zero exponentially in the mean square while the disturbance rejection attenuation is constrained to a give level by means of the H∞ performance index.
Abstract: In this paper, the robust H∞ filtering problem is studied for a class of uncertain nonlinear networked systems with both multiple stochastic time-varying communication delays and multiple packet dropouts. A sequence of random variables, all of which are mutually independent but obey Bernoulli distribution, are introduced to account for the randomly occurred communication delays. The packet dropout phenomenon occurs in a random way and the occurrence probability for each sensor is governed by an individual random variable satisfying a certain probabilistic distribution in the interval. The discrete-time system under consideration is also subject to parameter uncertainties, state-dependent stochastic disturbances and sector-bounded nonlinearities. We aim to design a linear full-order filter such that the estimation error converges to zero exponentially in the mean square while the disturbance rejection attenuation is constrained to a give level by means of the H∞ performance index. Intensive stochastic analysis is carried out to obtain sufficient conditions for ensuring the exponential stability as well as prescribed H∞ performance for the overall filtering error dynamics, in the presence of random delays, random dropouts, nonlinearities, and the parameter uncertainties. These conditions are characterized in terms of the feasibility of a set of linear matrix inequalities (LMIs), and then the explicit expression is given for the desired filter parameters. Simulation results are employed to demonstrate the effectiveness of the proposed filter design technique in this paper.
TL;DR: A double image encryption by using random binary encoding and gyrator transform and an iterative structure composed of the random binary encode method is designed and employed for enhancing the security of encryption algorithm.
Abstract: We propose a double image encryption by using random binary encoding and gyrator transform. Two secret images are first regarded as the real part and imaginary part of complex function. Chaotic map is used for obtaining random binary matrix. The real part and imaginary part of complex function are exchanged under the control of random binary data. An iterative structure composed of the random binary encoding method is designed and employed for enhancing the security of encryption algorithm. The parameters in chaotic map and gyrator transform serve as the keys of this encryption scheme. Some numerical simulations have been made, to demonstrate the performance this algorithm.
TL;DR: P pH affected DBP formation differently, with THM increasing, HKs decreasing, and other DBPs having maximum concentrations at certain pH values, and the addition of ammonia significantly reduced the formation of most DBPs, but TCNM formation was not affected and 1,1-dichloropropanone formation was higher with the additions of ammonia.