Showing papers by "University of Electronic Science and Technology of China published in 2008"
TL;DR: A method that combines increment of diversity with modified Mahalanobis Discriminant, called IDQD, is presented to predict 208 OMPs, 206 transmembrane helical proteins (TMHPs) and 673 globular proteins (GPs) by using Chou's pseudo amino acid compositions as parameters, suggesting that the pseudo aminoacid composition can better reflect the core feature of membrane proteins than the classical amino acid composition.
242 citations
TL;DR: In this article, the optical constants of the annealed ZnO thin film were determined in the ultraviolet region while increases in the visible region, and the effects of annealing temperature on optical constants were investigated.
234 citations
TL;DR: The structures of the lower and upper approximations based on arbitrary binary relations in the generalized rough sets are presented and an algorithm to compute atoms for these two Boolean algebras is presented.
229 citations
TL;DR: Wang et al. as discussed by the authors proposed a recommendation algorithm based on a weighted object network, which is sensitive to the configuration of initial resource distribution, and demonstrated that a degree-dependent initial configuration can outperform the uniform case for both accuracy and personalization strength.
Abstract: In this paper, based on a weighted object network, we propose a recommendation algorithm, which is sensitive to the configuration of initial resource distribution. Even under the simplest case with binary resource, the current algorithm has remarkably higher accuracy than the widely applied global ranking method and collaborative filtering. Furthermore, we introduce a free parameter β to regulate the initial configuration of resource. The numerical results indicate that decreasing the initial resource located on popular objects can further improve the algorithmic accuracy. More significantly, we argue that a better algorithm should simultaneously have higher accuracy and be more personal. According to a newly proposed measure about the degree of personalization, we demonstrate that a degree-dependent initial configuration can outperform the uniform case for both accuracy and personalization strength.
203 citations
TL;DR: Steady-state visual evoked potentials (SSVEP) differences were strongly related to the frequency spectrum differences of the flickers and the stimulator was selected based on the complexity of the BCI system.
194 citations
TL;DR: In this article, the properties of water and their changes under the action of a magnetic field were gathered by the spectrum techniques of infrared, Raman, visible, ultraviolet and X-ray lights, which may give an insight into molecular and atomic structures of water.
Abstract: The properties of water and their changes under the action of a magnetic field were gathered by the spectrum techniques of infrared, Raman, visible, ultraviolet and X-ray lights, which may give an insight into molecular and atomic structures of water. It was found that some properties of water were changed, and a lot of new and strange phenomena were discovered after magnetization. Magnetized water really has magnetism, which has been verified by a peak shift of X-ray diffraction of magnetized water + Fe(3)O(4) hybrid relative to that of pure water + Fe(3)O(4) hybrid, that is a saturation and memory effect. The properties of infrared and ultraviolet absorptions, Raman scattering and X-ray diffraction of magnetized water were greatly changed relative to those of pure water; their strengths of peaks were all increased, the frequencies of some peaks did also shift, and some new peaks, for example, at 5198, 8050 and 9340 cm(-1), occurred at 25 degrees C after water was magnetized. In the meanwhile, the magnetized effects of water are related to the magnetized time, the intensity of an externally applied magnetic field, and the temperature of water, but they are not a linear relationship. The study also showed a lot of new and unusual properties of magnetized water, for example, the six peaks in 3000-3800 cm(-1) in infrared absorption, the exponential increase of ultraviolet absorption of wave with the decreasing wavelength of light of 200-300 nm, the frequency-shifts of peaks, a strange irreversible effect in the increasing and decreasing processes, as well as a stronger peak of absorption occurring at 50 degrees C, 70 degrees C and 80 degrees C, the existence of many models of motion from 85 degrees C to 95 degrees C in 8000-10000 cm(-1), and so on. These results show that the molecular structure of water is very complicated, which needs further study. Furthermore, the macroscopic feature of mechanics, for instance, surface tension force of magnetized water, was also measured. Experiments discovered that the size in contact angles of magnetized water on the surface of hydrophobic materials decreases, thus the surface tension force of magnetized water decreases relative to that of pure water. It is seen from the above results that the clustering structure of hydrogen-bonded chains and polarization effects of water molecules are enhanced after magnetization. These results are helpful in revealing the mechanism of magnetization of water.
188 citations
TL;DR: In this paper, a PANI/titanium dioxide (PANI/TiO 2 ) nanocomposite thin films were processed on a silicon substrate with gold interdigital electrodes by an in-situ self-assembly approach for NH 3 gas-sensing application.
Abstract: Polyaniline/titanium dioxide (PANI/TiO 2 ) nanocomposite thin films were processed on a silicon substrate with gold interdigital electrodes by an in-situ self-assembly approach for NH 3 gas-sensing application, and the effect of polymerization temperature on the gas response of the PANI/TiO 2 thin film gas sensor was investigated. The results showed that the PANI/TiO 2 thin film prepared at 10 °C was superior to those prepared at other temperatures in terms of response properties, which also exhibited good reproducibility, selectivity and long-term stability. UV–vis absorption and surface morphology characterization of the nanocomposite thin films were performed to explain these different gas-sensing properties. The sensing mechanism was also discussed.
185 citations
TL;DR: The results of jackknife cross-validation for 450 non-redundant proteins show that the overall predicted successful rates of SVM and IDQD are 82.2% and 79.1%, respectively, which are higher than other existing methods.
Abstract: The successful prediction of protein subcellular localization directly from protein primary sequence is useful to protein function prediction and drug discovery. In this paper, by using the concept of pseudo amino acid composition (PseAAC), the mycobacterial proteins are studied and predicted by support vector machine (SVM) and increment of diversity combined with modified Mahalanobis Discriminant (IDQD). The results of jackknife cross-validation for 450 non-redundant proteins show that the overall predicted successful rates of SVM and IDQD are 82.2% and 79.1%, respectively. Compared with other existing methods, SVM combined with PseAAC display higher accuracies.
182 citations
TL;DR: In this paper, the effects of magnetic field on microscopic structures and macroscopic properties of water are studied by the spectrum techniques of infrared, Raman, visible, ultraviolet lights and X-ray.
Abstract: Influences of magnetic field on microscopic structures and macroscopic properties of water are studied by the spectrum techniques of infrared, Raman, visible, ultraviolet lights and X-ray. From these investigations, we know that the magnetic fields change the distribution of molecules and electrons, cause displacements and polarization of molecules and atoms, result in changes of dipole-moment transition and vibrational states of molecules and variation of transition probability of electrons, but does not alter the constitution of molecules and atoms. These are helpful in seeking the mechanism of magnetization of water. Meanwhile, we also measure the changed rules of the surface tension force, soaking effect or angle of contact, viscosity, rheology features, refraction index, dielectric constant and electric conductivity of magnetized water relative to that of pure water. The results show that the magnetic fields increase the soaking degree and hydrophobicity of water to materials, depress its surface-tension force, diminish the viscosity of war, enhance the feature of plastic flowing of water, and increase the refraction index, dielectric constant and electric conductivity of water after magnetization. These changes are caused by the above changes of microscopic structures under the action of magnetic field. Therefore, our studies are significant in science and has practical value of applications.
177 citations
TL;DR: XPS analysis showed that Fe3+ was not on the surface of TiO2 nanoparticles, but inserting into the matrix interior, and the photoactivity degradation of MB on Fe-doped TiO 2 nanoparticles decreased.
173 citations
TL;DR: A novel semi-supervised feature selection algorithm, which makes use of both labeled and unlabeled data points, which is compared with Fisher score and Laplacian score on face recognition and demonstrates the efficiency and effectiveness of the algorithm.
TL;DR: This paper presents the taxonomy of the multicast routing protocols, their properties and design features, and aims to aid MANETs researchers and application developers in selecting appropriate multicasts routing protocols for their work.
TL;DR: In this paper, the authors improved the analysis to deal with charged fermion tunnelling from general dilatonic black holes, specifically including the charged, spherically symmetric, and rotating Kaluza-Klein black holes.
Abstract: Kerner and Mann's recent work shows that for an uncharged and non-rotating black hole its Hawking temperature can be correctly derived by fermions tunnelling from its horizons. In this paper, our main work is to improve the analysis to deal with charged fermion tunnelling from the general dilatonic black holes, specifically including the charged, spherically symmetric dilatonic black hole, the rotating Einstein–Maxwell–dilaton–axion (EMDA) black hole and the rotating Kaluza–Klein (KK) black hole. As a result, the correct Hawking temperatures are well recovered by charged fermions tunnelling from these black holes.
TL;DR: A new low-temperature procedure has been used for preparing micro-mesoporous carbon-doped TiO2 photocatalysts, with anatase pore wall and substitutional carbon occupying oxygen sites, which exhibit outstanding photoc atalytic activity under visible light irradiation.
TL;DR: In this paper, the authors presented a fiber-optic refractive index sensor which is based on an intrinsic Fabry-Perot interferometer (IFPI) formed by a section of singlemode photonic crystal fiber and conventional single-mode fiber.
Abstract: This paper, for the first time to the best of our knowledge, presents a novel fiber-optic refractive-index sensor which is based on an intrinsic Fabry-Perot interferometer (IFPI) formed by a section of endlessly single-mode photonic crystal fiber (EPCF) and conventional single-mode fiber. Such an IFPI sensor has the advantages of easy fabrication, low joint and transmission losses, low-cost and good fringe visibility due to the use of the EPCF. This miniature fiber-optic sensor is demonstrated for the measurement of the refractive index change of glycerin solution by measuring its fringe visibility change solely. The experimental data agree well with the theoretical results and the refractive-index resolution and repeatability of ∼2 × 10−5 and ±0.5%FS in the linear operating range, are achieved. In addition, such a sensor can be used as an excellent temperature sensor with a cavity-length-temperature sensitivity of 4.16 nm/°C and repeatability of ±0.15%FS when tested from 20 °C to 100 °C. Therefore, simultaneous measurement of refractive index and temperature can be realized by determination of the fringe visibility and the cavity length change of such a PCF-based IFPI, respectively, providing a practical way to measure refractive index with self-temperature compensation.
TL;DR: This paper develops a fixed and a variable relay sensing scheme to improve the spectrum sensing capabilities of centralized cognitive radio (CR) networks and studies the network outage probabilities to compare the performances of the fixed and variable relay schemes.
Abstract: Cognitive radio networks need to continuously monitor spectrum to detect the presence of the licensed users. In this paper, we have exploited spatial diversity in multiuser networks to improve the spectrum sensing capabilities of centralized cognitive radio (CR) networks. We develop a fixed and a variable relay sensing scheme. The fixed relay scheme employs a relay that has a fixed location to help the cognitive network base station detect the presence of the primary user. The variable relay sensing scheme employs cognitive users distributed at various locations as relays to sense data and to improve the detection capabilities. This effectively reduces the average detection time by exploiting spatial diversity inherent in multiuser networks. Finally, we study the network outage probabilities to compare the performances of the fixed and variable relay schemes.
TL;DR: Experiments show that the fractional differential-based image operator has excellent feedback for enhancing the textural details of rich-grained digital images.
Abstract: This paper mainly discusses fractional differential approach to detecting textural features of digital image and its fractional differential filter. Firstly, both the geometric meaning and the kinetic physical meaning of fractional differential are clearly explained in view of information theory and kinetics, respectively. Secondly, it puts forward and discusses the definitions and theories of fractional stationary point, fractional equilibrium coefficient, fractional stable coefficient, and fractional grayscale co-occurrence matrix. At the same time, it particularly discusses fractional grayscale co-occurrence matrix approach to detecting textural features of digital image. Thirdly, it discusses in detail the structures and parameters of n×n any order fractional differential mask on negative x-coordinate, positive x-coordinate, negative y-coordinate, positive y-coordinate, left downward diagonal, left upward diagonal, right downward diagonal, and right upward diagonal, respectively. Furthermore, it discusses the numerical implementation algorithms of fractional differential mask for digital image. Lastly, based on the above-mentioned discussion, it puts forward and discusses the theory and implementation of fractional differential filter for digital image. Experiments show that the fractional differential-based image operator has excellent feedback for enhancing the textural details of rich-grained digital images.
TL;DR: In this paper, the authors examined the microwave electromagnetic and microwave-absorbing properties of the as-prepared and annealed (1400 °C in Ar) T-CNCs systematically.
Abstract: Twin carbon nanocoils (T-CNCs) were synthesized by means of acetylene decomposition over nickel nanoparticles. From the TEM image, one can see the growth of carbon nanocoils from the opposite sides of a nickel nanodisc, making an interangle of 180°. We examined the microwave electromagnetic (EM) and microwave-absorbing properties of the as-prepared and annealed (1400 °C in Ar) T-CNCs systematically. A composite containing the as-prepared T-CNCs (15 wt %) and paraffin exhibited strong microwave absorption in a frequency range of 2 to 18 GHz. Over an absorber of double-layered composite (2.5 and 3.5 mm thickness), an absorption bandwidth of ca. 10 GHz corresponding to reflection loss below −10 dB can be obtained. We found that the magnetic parameters of the composite are low and suggest that the good absorption properties of T-CNCs should be attributed to dielectric rather than magnetic loss. It was observed that the as-prepared T-CNCs are superior to the annealed T-CNCs in microwave absorption ability, and...
TL;DR: In this article, a simple and effective route to prepare zinc oxide nanoparticle with higher photocatalytic activity through depositing zinc oxide on the silica particle surface, moreover, the catalyst is easier to recover due to its higher density.
TL;DR: Vanadium and nitrogen co-doped TiO2 nanocrystal (4-5nm) photocatalysts were prepared through direct nitridation of the controlled hydrolysis product of Tetrabutyl titanate in V (IV) ions solution.
TL;DR: In this article, a hydrothermal method was used to synthesize potassium niobate (KNbO3) nanowires, which are well-crystallized with orthorhombic structure.
Abstract: Potassium niobate (KNbO3) nanowires were synthesized by a hydrothermal method. X-ray diffraction and Raman spectroscopy indicated the nanowires are well-crystallized with orthorhombic structure. Hi...
TL;DR: In this paper, Fe3+-doped SnO2 nanoparticles were prepared by solgel-calcination and sol-gel-hydrothermal routes, respectively, and their microstructure as well as physical and chemical properties have been characterized and compared.
19 May 2008
TL;DR: This analysis suggests that while the proposed DSRC standard may account for Doppler and delay spreads in vehicular channels, large packets may face higher error rates due to time-varying channels.
Abstract: We present a GPS-enabled channel sounding platform for measuring both vehicle-to-vehicle and vehicle-to- roadside wireless channels. This platform was used to conduct an extensive field measurement campaign involving vehicular wireless channels across a wide variety of speeds and line-of-sight conditions. From the data, we present statistical characterizations of several classes of these channels at 5.9 GHz. This analysis suggests that while the proposed DSRC standard may account for Doppler and delay spreads in vehicular channels, large packets may face higher error rates due to time-varying channels.
TL;DR: In this paper, a generalized gradient of the output with respect to the input of the hysteresis and the derivative of the input that represents the frequency change of input are introduced into the input space.
Abstract: A method for the identification of the rate-dependent hysteresis in piezoceramic actuators is proposed. In this approach, both a so-called generalized gradient of the output with respect to the input of the hysteresis and the derivative of the input that represents the frequency change of the input are introduced into the input space. Then an expanded input space is established. Thus, the multi-valued mapping of the rate-dependent hysteresis can be transformed into a one-to-one mapping based on the expanded of the input space. In this case, the neural network method can be applied to the modeling of the rate-dependent hysteresis. Finally, the experimental results are presented to illustrate the performance of the proposed approach.
TL;DR: In this article, a two-step Suzuki coupling reaction was used to synthesize blue light-emitting anthracene derivatives endcapped with triphenylamine for efficient hole transportation.
Abstract: Blue light-emitting anthracene derivatives end-capped with triphenylamine for efficient hole transportation have been designed and synthesized using two-step Suzuki coupling reactions. The compounds possess high glass transition temperatures for good thermal stability and strong blue emission in solution. Typical three-layer organic light-emitting devices (OLEDs) made from these compounds show highly efficient blue emission, which are better than or comparable to state-of-the-art fluorescent OLEDs performance. For example, 9-pyrenyl-10-(4-triphenylamine) anthrancene (PAA)-based nondoped device exhibits efficient blue emission with a maximum efficiency up to 7.9 cd/A (or 6.8 lm/W). Based on the good hole transport of the anthracene-triphenylamine derivatives, deep blue emitting devices with high efficiency were achieved by using the derivatives as both emitter and hole transporter.
TL;DR: It is shown that even in technical replicate tests using identical samples, it is highly likely that the selected DEG lists will be very inconsistent in the presence of small measurement variations, and the apparently low reproducibility of DEG detection from current technical replicate Tests does not indicate low quality of microarray technology.
Abstract: Motivation: Differentially expressed gene (DEG) lists detected from different microarray studies for a same disease are often highly inconsistent. Even in technical replicate tests using identical samples, DEG detection still shows very low reproducibility. It is often believed that current small microarray studies will largely introduce false discoveries.
Results: Based on a statistical model, we show that even in technical replicate tests using identical samples, it is highly likely that the selected DEG lists will be very inconsistent in the presence of small measurement variations. Therefore, the apparently low reproducibility of DEG detection from current technical replicate tests does not indicate low quality of microarray technology. We also demonstrate that heterogeneous biological variations existing in real cancer data will further reduce the overall reproducibility of DEG detection. Nevertheless, in small subsamples from both simulated and real data, the actual false discovery rate (FDR) for each DEG list tends to be low, suggesting that each separately determined list may comprise mostly true DEGs. Rather than simply counting the overlaps of the discovery lists from different studies for a complex disease, novel metrics are needed for evaluating the reproducibility of discoveries characterized with correlated molecular changes.
Contact:guoz@ems.hrbmu.edu.cn; lixia@ems.hrbmu.edu.cn
Supplementaty information: Supplementary data are available at Bioinformatics online.
01 Mar 2008
TL;DR: A mathematical programming model is proposed that addresses speed and scalability issues in data mining and knowledge discovery and applied the model to Credit Classification Problems and the theoretical relationship between the proposed MCQP model and SVM was discussed.
Abstract: Speed and scalability are two essential issues in data mining and knowledge discovery. This paper proposed a mathematical programming model that addresses these two issues and applied the model to Credit Classification Problems. The proposed Multi-criteria Convex Quadric Programming (MCQP) model is highly efficient (computing time complexity O(n^1^.^5^-^2)) and scalable to massive problems (size of O(10^9)) because it only needs to solve linear equations to find the global optimal solution. Kernel functions were introduced to the model to solve nonlinear problems. In addition, the theoretical relationship between the proposed MCQP model and SVM was discussed.
TL;DR: The novel MDES opens up an effective and robust approach for global optimization problems and improves the performance of the algorithm significantly, in terms of both the convergence rate and the exploration ability.
Abstract: A high convergence rate and a robust exploration ability constitute a contradiction in modern heuristic optimization techniques. This paper describes a modified differential evolution strategy (MDES) that builds up a balanced relationship between the two contradictive elements by introducing several modifications into the conventional differential evolution strategy (DES). The novel MDES opens up an effective and robust approach for global optimization problems. Several representative mathematical functions are minimized using various optimization methods and the convergence rates are compared to evaluate the performance of MDES. Moreover, array synthesis examples which can be formulated as non-convex problems are presented, including the optimal synthesis of sum and difference patterns and the synthesis of unequally spaced arrays. Numerical results demonstrate that the proposed approach improves the performance of the algorithm significantly, in terms of both the convergence rate and the exploration ability.
TL;DR: In this paper, a matrix splitting algorithm is developed to break up the texture limit, which splits the huge matrix into multiple, tiny matrixes, each of which can be fit into one texture.
Abstract: The graphics processing unit (GPU) has been used to speed up the conventional method of moments (MoM) calculations for electromagnetic scattering from arbitrary three-dimensional conducting objects. The acceleration ratio of filling impedance matrix has reached 30, while the total acceleration ratio (including iteration) is about 20. Moreover, a matrix splitting algorithm is developed to break up the texture limit. It splits the huge matrix into multiple, tiny matrixes, each of which can be fit into one texture. Then, the system memory can be used to store all the elements of the impedance matrix, making it possible to deal with electrically large problems, since the capacity of video card's memory is no longer a limit.
TL;DR: In this paper, a simple hydrothermal method was used to synthesize Co-doped SnO(2) nanoparticles, which were characterized by X-ray diffraction (XRD), XPS, Transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectra (DRS) and Photoluminescence spectroscopy (PL).
Abstract: Co-doped SnO(2) nanoparticles were synthesized by a simple hydrothermal method, and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectra (DRS) and Photoluminescence spectroscopy (PL). It is found that the SnO(2) crystallites with the tetragonal rutile structure formed directly during the hydrothermal process without calcination. The Co-doped SnO(2) nanoparticles were spheric and well-dispersed with narrow size distribution. The crystalline size of SnO(2) decreased from 5.98 to 2.22 nm when the Co content increased from 0% to 20%. A considerable red shift in the absorbing band edge was observed with increasing of Co dopant.