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Biometrics has the advantages of efficiency and convenience in identity authentication. As one of the most promising biometric-based methods, ear recognition has received broad attention and research. Previous studies have achieved remarkable performance with multiple samples per person (MSPP) in the gallery. However, most conventional methods are insufficient when there is only one sample per person (OSPP) available in the gallery. To solve the OSPP problem by maximizing the use of a single sample, this paper proposes a hybrid multi-keypoint descriptor sparse representation-based classification (MKD-SRC) ear recognition approach based on 2D and 3D information. Because most 3D sensors capture 3D data accessorizing the corresponding 2D data, it is sensible to use both types of information. First, the ear region is extracted from the profile. Second, keypoints are detected and described for both the 2D texture image and 3D range image. Then, the hybrid MKD-SRC algorithm is used to complete the recognition with only OSPP in the gallery. Experimental results on a benchmark dataset have demonstrated the feasibility and effectiveness of the proposed method in resolving the OSPP problem. A Rank-one recognition rate of 96.4% is achieved for a gallery of 415 subjects, and the time involved in the computation is satisfactory compared to conventional methods.

Cross-modify are the main point of product designing. CATIA V5 software is widely used in automobile, aircraft and other fields. During using CATIA V5, it is a fatal problem for every designer to how to improve the efficiency of modification in the product designing and avoid feature failure. After long-term practice, robust design method is introduced in this paper to solve this problem. It is easy to modify the feature and remain association. It shortens the period of subsequent improvements effectively and provides the assurance for product updating.

The “Rheological hybrid” effect, a phenomenon in which the melt viscosity of a ternary polymer blend decreases with increasing filler loading, due to the influence of the minor polymer phase in the blend, was investigated for Nylon 6/liquid crystalline polymer (LCP) blends after the addition of glass beads (GB). The apparent viscosity of the blended melts was measured by means of capillary rheometry. The viscosity of ternary Nylon 6/GB/LCP hybrid blends was the lowest among all the melts, i.e. lower than that of neat Nylon 6, LCP, binary Nylon 6/LCP and Nylon 6/GB blends. The viscosity of ternary Nylon 6/GB/LCP hybrid blends decreased with increasing glass bead content. Correspondingly, the morphology of the LCP droplets changed from spherical to fibrous with increasing glass bead content as well. For ternary hybrid blends with the same glass bead content and different bead sizes, the blend containing the smallest beads (1.2 μm in the diameter) had the lowest viscosity and strongest tendency to LCP fibrillation. A mechanism was proposed for correlating the rheological hybrid effect with LCP fibrillation in these ternary hybrid blends.

Polycarbonate (PC) was melt blended with small amount of liquid-crystalline polymer (LCP) and various contents of glass beads (GB) having different diameters. The rheological measurements indicated that the GB addition increased the viscosity ratio and seemed unfavorable to the LCP fibrillation. However, the morphological observation showed that the LCP fibrillation was promoted by the GB addition and varied with the GB packing. With the increased GB packing by increasing the GB content and/or decreasing the GB diameter, LCP deformed from spheres and ellipsoids into stretched ellipsoids at lower shear rates and into long fibrils at higher shear rates. Although higher content of smaller GB jammed into the larger LCP droplets and inhibited the LCP fibrillation, very long LCP fibrils formed at higher shear rates at a high enough packing of GB. The relationship between GB packing and LCP fibrillation revealed two kinds of hydrodynamic effects of GB promoting the LCP fibrillation: at lower GB packing, the shear flow was enhanced by the high local shear between GB, in quantity; and for a high enough GB packing, the shear flow was changed, in quality, into elongational flow, which was more effective for the LCP fibrillation. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1020–1030, 2006

Gelcasting of ceramic components with the soldium alginate (Na-Alginate) as gelformers has received increasing attention. The aim of the present study is to improve the flexural strength of green body gelcast from nontoxic Na-alginate system by introducing a proper amount of water-soluble polymer, PVP. The rheological properties and gelling characteristics of PVP–Na-Alginate/Al2O3 suspensions were examined. Ceramic parts with uniform and homogeneous structure were fabricated as well as flexural strength and microstructure of the gelcast green and sintered bodies were highlighted.

A common and fatal problem of the low-toxicity gelcasting is the low flexural strength of green bodies. The objective of this study was to solve the problem by introducing water-soluble polyvinylpyrrolidone (PVP) polymer to the monomer system. The low-toxicity monomer and ceramic powder were selected as methacrylamide (MAM) and alumina, respectively. Flexural strength of green bodies was improved nearly by 30%, with no significant change in the property of sintered bodies when the addition amount of PVP is 2.8 wt.%. Influence of PVP content on rheological properties of alumina suspensions, their gelation time, and the microstructure of green and sintered bodies were investigated.

Aqueous gelcasting with a low toxicity monomer system has attracted increasing attention. The present study attempts to enhance the flexural strength of green bodies gelcast from a low toxicity hydroxyethyl methacrylate (HEMA) system by introducing an appropriate amount of the water soluble polymer polyvinylpyrrolidone (PVP). The rheological properties and gelling characteristics of PVP–HEMA/Al2O3 suspensions were examined. In addition, the flexural strength and microstructure of the gelcast green and sintered bodies are discussed.

The hierarchical structure of thermotropic liquid crystalline polymer (TLCP), especially microfibrils with an average diameter of 30 nm has been obtained in polyamide 6 (PA6)/TLCP/glass bead (GB) ternary blends by capillary flows. Thermodynamically the different interfacial tensions between PA6 and GB, and between TLCP and GB, make the glass beads migrate to the vicinity of the TLCP melt droplets. Then the strong extensional flow field formed by the micro-rollers of these glass beads exerts strong extensional action on TLCP coils so that results in the formation of TLCP microfibrils, which are usually generated with neat TLCP melt only. The hierarchical structure of thermotropic liquid crystalline polymer (TLCP) in PA6/TLCP/GB ternary blends can enhance mechanical performance of such blends.

Three polycarbonate (PC) composites that were reinforced, respectively, with liquid crystalline polymer (LCP), glass fibers, and both of them were prepared by a single injection-molding process. The role of LCP in improving the processibility of the composites was characterized by torque measurement test. The transitions of LCP morphology in two- and three-component composites were investigated by using polarizing optical microscopy and scanning electron microscopy. The micrographs showed a skin–core gradient structure in all three systems investigated, and the addition of glass fiber to the PC/LCP blend affected the morphological transition and content distribution of dispersed LCP phase through the thickness of the injection-molded samples. These results were correlated well with the measurements of tensile mechanical properties and dynamic mechanical analysis. How to fully use the dispersed LCP phase in PC in situ hybrid composites was discussed for the thickness change of core layer and the heterogeneous distribution of more LCP in the core. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 625–634, 2004

The sintering and compositional dependencies of dielectric properties in PMW–PT–PNN ceramics have been investigated. The present work confirms that sintering temperature had a large influence on the dielectric properties in this ternary system. It was found that the main causes for the flat temperature dependence are due to shifting and broadening of the dielectric anomaly.

The terpolymer of disodium itaconate (DIA), acrylamide (AM) and sodium 2-acrylamido-2-methyl-1-propane sulfonate (SAMPS) was synthesized through free-radical polymerization, and characterized using FTIR and TGA methods. The IR spectra of DIA-AM-SAMPS terpolymer confirmed that there was no olefinic band at 1635–1620 cm−1, while the TGA results revealed that the terpolymer was of higher thermal stability than the SAMPS homopolymer. The filtrate volume reduced with increase of the terpolymer concentration before or after the aging test. The rheology properties of both fresh-water mud and salt-water mud were improved by DIA-AM-SAMPS terpolymer, and apparent viscosity (ηa); plastic viscosity (ηb) and yield point (τ0) of salt-water mud reached the smallest values at 1.2% of the terpolymer concentration after the aging test. The particle size data demonstrated that only a small change of the clay particle size occurred before and after the aging test at 220°C. This further confirmed the thermal stability of the terpolymer–clay dispersion from another point of view. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3068–3075, 2002; DOI 10.1002/app.2335

The available images of biometrics recognition system in real-world applications are often degraded and of low-resolution, making the acquired images contain less detail information. Therefore, biometrics recognition of the low-resolution image is a challenging problem. It has received increasing attention in recent years. In this paper, a two-step ear recognition scheme based on super-resolution is proposed, which will contribute to both human-based and machine-based recognition. Unlike most standard super-resolution methods which aim to improve the visual quality of ordinary images, the proposed super-resolution based method is designed to improve the recognition performance of low-resolution ear image, which uses LC-KSVD algorithm to learn much more discriminative atoms of the dictionary. When applied to low-resolution ear recognition problem, the proposed method achieves better recognition performance compared with the present super-resolution method.

The forpolymer of N-vinylpyrrolidone (NVP), itaconic acid (IA), acrylamide (AM) and 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) was synthesized through free-radical polymerization and was characterized using Fourier transform IR spectroscopy. The colloidal properties of the drilling fluid were investigated in the form of fresh-water or salt-water mud. It was found that the NVP–IA–AM–AMPS forpolymer had strong effects on the properties of the mud. The filtrate volume decreased with the increase of the forpolymer concentration before or after the aging test at 220 °C, and the filtrate volume after the aging test was larger than that before the aging test, but was still very small compared with the corresponding base mud. In addition, the rheological properties of both fresh-water mud and salt-water mud were modified by the forpolymer. The particle size data demonstrated that the average size of the clay particle after the aging test was larger than that before the aging test and that the particle size of the fresh-water mud was narrower compared with that of the salt-water mud before and after the aging test, respectively. The drilling fluid containing the forpolymer had an excellent tolerance to salt and high temperature.

In this study, a new physically based multiscalar drought index, the Standardized Moisture Anomaly Index (SZI), was developed and evaluated, which combines the advantages of the Palmer Drought Severity Index (PDSI) and the Standardized Precipitation Evapotranspiration Index (SPEI). The SZI is based on the water budget simulations produced with a sophisticated hydrological model, and it also includes a multiscalar feature to quantify drought events at different temporal scales taken from SPEI. The Chinese Loess Plateau was selected to evaluate the performance of the SZI. Our evaluation indicates that the SZI accurately captures the onset, duration, and ending of a multiyear drought event through its multiscalar feature, while the PDSI, which lacks this feature, is often unable to describe the evolution of a multiyear drought event. In addition, the variability of the SZI is more consistent with observed streamflow and the satellite normalized difference vegetation index than that of the Standardized Precipitation Index and the SPEI. Although the SPEI includes potential evapotranspiration (PE) as water demand, water demand is often unrealistically estimated based solely on PE, especially over arid and semiarid regions. The improved drought quantification with the SZI is the result of a more reasonable estimation of water demand by including evapotranspiration, runoff, and any change in soil moisture storage. In general, our newly developed SZI is physically based and includes a multiscalar feature, which enables it to provide better information for drought monitoring and identification at different temporal scales.

This paper proposes a multiscale 3D keypoint detection method based on local weighted dissimilarity measure. At first, compute the local weighted dissimilarity measure of each vertex at different scale. Then determine the detecting scale of each vertex. Finally compare the local weighted dissimilarity measure of each vertex with those of its neighboring surface points at its detecting scale. The keypoint is defined as the vertex that has highest local weighted dissimilarity measure in its neighborhood. The contribution of this paper includes that we propose a novel local weighted dissimilarity measure and the frame of multiscale keypoint detection method. The proposed local weighted dissimilarity measure is computed from the shape index value, and it is invariable to rotation and translation transformation. The multiscale algorithm frame enable the detected key points are robust to noise, especially to high level noise. Extensive experiments have performed to testify the effectiveness of the proposed method.

As a promising biometrics, ear recognition is attracting increasing research interests among researchers in recent years. It has a wide range of civilian and law-enforcement applications. In this paper, a new feature extraction approach is investigated for ear recognition by using scale information of multi-scale Gabor filters. Compared with augmented Gabor features defined via concatenation of the Gabor filtering coefficients, the proposed Gabor scale feature will not only avoid too much redundancy but also tend to extract more precise structural information. So, the proposed feature is more robust to ear image variations. Rigorous experimental results on the ear image dataset of UND and USTB database III show the effectiveness of the proposed Gabor scale feature for ear recognition.

This paper presents a novel planar metrology method based on image sequence. Compared with the planar metrology method based on single image, the proposed method can enlarge the measuring range effectively. The main reference planar template and the auxiliary reference planar template are used to achieve the transformation between the three-dimensional coordinate systems of different images. The auxiliary reference planar template of the former image is the main reference planar template of the latter image, and their positions remain invariant in the process of the metrology. The main reference planar template are used to obtain the 3D measuring information and the auxiliary reference planar template are used to transform the coordinates of feature points to the same three-dimensional coordinate system. Extensive experimental results show that the proposed method can meet the need of the metrology of the large scene.

At present time, grating mechanical scoring manufacture is process that diamond score reciprocates on the Aluminum film which is vacuum coating on the Chrome, glass and other substrates. As the structure and properties of stream Aluminum film affect the quality of groove greatly and are limited by the vacuum steam process, it is difficult to control and test the microstructure and mechanical properties of the film. In this paper, we recommend the new method that combine X-ray diffraction "nondestructive" test and nanopress-scratch testing technology. We can calculate the micro-structure, the aluminum film thickness and residual stress, analysis on the mechanical properties such as elastic modulus, hardness and stress-strain curve in this method in order to unveil the microstructure and mechanical properties of the aluminum film. Provide a feasible method for studying the microstructure and mechanical properties of the film and valuable reference and guidance on grating mechanical technology.

This article proposes a physical model for liquid quench of solid rocket motor and presents the results of experimental study. It is found that there is a critical value of injection pressure drop during liquid quench of solid rocket motor. The critical value of injection pressure drop increases with propellant energy (gy). The additive selected appropriately added in liquid is able to reduce significantly the liquid quantity required (LQR) Ws, for extinction of solid rocket motor. LQR reduced by the addition of 0.5% CE by weight in water are about 35 and 25% for double base propellant and nonmetalized polyurethane-ammonium perchlorate composite propellant, respectively. LQR is mainly dependent upon the propellant energy, i.e., it increases with increasing propellant energy. For pure water, Ws * O.lg^and for water + 0.5% CE, Ws * 0.76gy* The variation of LQR with the chamber pressure is related to pressure exponent of propellant (n). If n > 0, it increases with increasing chamber pressure; and if n < 0, it decreases with increasing chamber pressure. With the injection pressure drop increasing, LQR decreases and the depressurization rate of solid rocket motor increases, respectively. The experimental results and the analysis indicate that the theoretical study on liquid quench of solid rocket motor should include the coupling effects of transient burning of propellant, heat transfer of liquid jet impinged on burning surface, evaporation of liquid droplets, and internal ballistics of rocket motor.

Summary The near-surface conditions of the Fushan sag are very complicated and the topographical relief is drastic. The lateral variation in thickness and the speed of weathering is intense and igneous rocks crop out. This results in a severely distorted time-distance curve, an unstable refraction layer, great changes in the shape of the record, a serious problem of non-surface-consistent statics, and rendering the conventional statics method unsuitable. All of these make the static correction of this area very difficult to solve. In this article we put forward an integrated statics approach including a tomographic inversion static correction based on uphole and marked layer, interactive layered and segmented first arrival static correction, global optimization reflection residual static correction and non-surface consistent static correction. A good result is achieved by using these methods, suggesting that our methods are feasible.

Summary The method of wavelet extraction from a seismic record is a typical problem in the processing of seismic data. Provided that the seismic wavelet is known, many problems about seismic data processing and the inversion of seismic attributes can be solved completely. In order to solve this problem, many methods of wavelet extraction and decomposition have been introduced. But every method has its limitation and prerequisites. Based on systemic analysis of previous methods of wavelet extraction, this paper presents a method which uses the wavelet amplitude spectrum to decompose the wavelet into minimum and maximum phase components. The group of wavelets with the same amplitude spectrum and different phase spectrum can be found in the cepstrum domain. According to the criterion of maximum variance module and the previous information and processing objectives, with an interactive processing tool, users can select optimum wavelets among the wavelet group. Furthermore, the seismic resolution can be improved by using the extracted wavelet to do wavelet deconvolution and wavelet zero-phasing. Wavelets have been extracted from theoretical records and real seismic data, and the tests for improving resolution also have been carried out with the extracted wavelets. Examples showed the validity and effectiveness of this method.

International audience; The effect of melt mixing on the interaction between multi-walled carbon nanotubes (MWNTs) and polystyrene (PS) matrix has been investigated. The interaction between pristine MWNTs and PS in solution was found to exist but not strong enough to allow MWNTs to be soluble in solvent. In contrast, this interaction between MWNTs and PS was significantly enhanced by melt mixing, which led to increased amount of PS-functionalized MWNT exhibiting good solubility in some solvents. The mechanism of melt mixing on this enhanced interaction was attributed to both chemical bonding and physical interaction during the melt mixing.

Improving resolution essentially is to eliminate the influence by the seismic wavelet and to recover the reflection coefficient sequence of the formation. Although there are many methods for resolution improvement today, the results are strongly affected by the constant time-space parameters, the noise, and absorption. In order to improve the resolution by modifying the spectrum in 3D time and space variable, first zero-phase deconvolution of seismic data in frequency domain is done by fitting seismic wavelet in different frequency bands and different time windows, then interactively compare the consequence between the deconvoluted and the original seismic trace on the screen to select the desired parameters based on the geological requirements. Finally “color compensation” will be made to the spectrum of different time windows picked from the selected deconvolution result. Processing results show that both the resolution and the depositional characteristics of the sections by this method are better than the conventional resolution improving method, especially when the structure is complex and the formation dip is steep.

The influence of well-dispersed nano-clay filler on the morphology of thermotropic liquid crystalline polymer (TLCP) in nylon-6 matrix was investigated by melt extrusion process. The good dispersion of clay in the hybrid blends was confirmed by X-ray diffraction, transmission electron microscopy and rheological measurement. Morphological observation showed that the clay platelets had dramatic influences on the dispersion and deformation of TLCP phase. The TLCP droplets got smaller at the clay content ≤3 wt%, and deformed into fibrils at the clay content up to 5 and 7 wt%. The morphology evolution of TLCP in the hybrid blends, especially at 7 wt% of clay loading, was consistent well with the prediction based on the micro-rheology parameters such as the viscosity ratio of the dispersed phase to the matrix ( η d /η m ) and the ratio of capillary number to the critical capillary number (Ca/Ca crit ). This enhanced fibrillation of TLCP droplets was attributed to the role of nano-clay particles as a compatibilizer to improve the interfacial adhesion and to suppress the interfacial slip between TLCP and nylon phases in the melt, so that the shear stress was effectively transferred to the dispersed TLCP phase.

The Gabor wavelets have been experimentally verified to be a good approximation to the response of cortical neurons. A new feature extraction approach is investigated for ear recognition by using scale information of Gabor wavelets. The proposed Gabor scale feature conforms to human visual perception of objects from far to near. It can not only avoid too much redundancy in Gabor features but also tends to extract more precise structural information that is robust to image variations. Then, Gabor scale feature-based non-negative sparse representation classification (G-NSRC) is proposed for ear recognition under occlusion. Compared with SRC in which the sparse coding coefficients can be negative, the non-negativity of G-NSRC conforms to the intuitive notion of combing parts to form a whole and therefore is more consistent with the biological modeling of visual data. Additionally, the use of Gabor scale features increases the discriminative power of G-NSRC. Finally, the proposed classification paradigm is applied to occluded ear recognition. Experimental results demonstrate the effectiveness of our proposed algorithm. Especially when the ear is occluded, the proposed algorithm exhibits great robustness and achieves state-of-the-art recognition performance.

Starting with graphene oxide, we successfully prepared stable dispersions of reduced graphene oxide (RGO) in three hydrophilic ionic liquids (ILs) at relatively high concentration without using any surfactants/stabilizers.

A new organogelator, N,N′-bis (octadecyl)-L-(1-pyrenebutyric acid)-glutamic diamide (LPG), was designed and its interaction with pristine single-walled carbon nanotubes (SWNTs) in the gel state was investigated. It was found that LPG can form organogels with various kinds of organic solvents. Although SWNT itself is difficult to disperse into organic solvents, it can be well dispersed into LPG gel. The gelation process and the properties of the resulting nanocomposites were found to be closely related to the pyrene group in the gelator. The addition of SWNTs significantly decreased the critical gelation concentration of LPG, depressed the sol to gel transition temperature and prolonged the time required to form a gel. Rheological investigations of LPG organogels showed that the flow of nanocomposites became more resistant to the applied stress upon the incorporation of SWNTs. This happened presumably via effective dispersion of SWNTs into the LPG organogels through π–π interaction between the surface of SWNTs and the pyrene group of LPG. The textures of the nanocomposites were altered from layer structure to intertwined fibers upon the incorporation of SWNTs, which also supported the effective mixing of SWNTs into LPG organogels.

The Si3N4 ceramic reinforced with 30 wt% 3YZrO2(ZrO2 containing 3 mol%Y2O3 has been fabricated by two kinds of processes (hot press and presureless sintering). The ZrO2/Si3N4 composites exhibited a high fracture toughness and flexural strength, and lower thermal conductivity than Si3N4 matrix material. The ZrO2/Si3N4 composite is suggested to be a very hopeful candidate material as component of heat engine applications. In this paper, the microstructure and phase composition of the composites are studied by SEM and XRD. The toughening mechanism of ZrO2 in the ZrO2/Si3N4 composites is discussed.

Si3N4 composite piston cap is made of Si3N4 matrix adding Y2O3, TiC and A12O3. The microstructure of Si3N4 composite shows α —Si3N4 and whisker-like β —Si3N4 grains homogeneously distribute in the matrix. The second phase particles are spread in the α —Si3N4 grains. The reinforced mechanism of two phases is discussed. The Si3N4 composite piston cap has been worked for over 100 hrs at over 800 °C for 1500 r/min during the high or full power run without water cooling. Experimental results show two phases microstructure gives the high mechanical properties which can make the resistance to thermal shock and high temperature.