A noise-robust front-end for distributed speech recognition in mobile communications

This paper investigates a new front-end processing that aims at improving the performance of speech recognition in noisy mobile environments. This approach combines features based on conventional Mel-cepstral Coefficients (MFCCs), Line Spectral Frequencies (LSFs) and formant-like (FL) features to constitute robust multivariate feature vectors. The resulting front-end constitutes an alternative to the DSR-XAFE (XAFE: eXtended Audio Front-End) available in GSM mobile communications. Our results showed that for highly noisy speech, using the paradigm that combines these spectral cues leads to a significant improvement in recognition accuracy on the Aurora 2 task.     

Microwave irradiation under different pH conditions induced a decrease in β-lactoglobulin antigenicity

Whey proteins adjusted at pH values 2, 4.6, 9 and at the natural milk pH (pH 6.8) were subjected to microwave irradiation at 300 W for 20 min or 700 W for 10 min. The protein composition of treated and native whey proteins were evaluated by Lowry’s method and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The ability of treated whey to bind IgG polyclonal antibody was determined by an enzyme-linked immunosorbent assay (ELISA) using sera obtained from rabbit immunized to β-Lactoglobulin (β-Lg). Significantly higher losses in soluble protein concentrations were observed for microwave irradiated whey proteins at pH value 4.6 (35.6% at 300 W and 44.33% at 700 W) (P < 0.0001) compared with those irradiated at the natural milk pH (26% at 300 or 700 W). The electrophoretic patterns of these proteins revealed a considerable decrease in intensity of the band corresponding to α-lactalbumin but only a slight modification was observed for the electrophoretic profiles of β-lactoglobulin. The data obtained with a rabbit anti-β-lactoglobulin immunoglobulin indicated a low antigenic response for microwave-irradiated whey proteins at the natural milk pH (up to 29.32% as well as 300–700 W) (P < 0.001). The lowest antigenicity was observed for samples adjusted to pH 4.6 followed by microwave irradiation at 300 or 700 W (46.99% at 300 W and 41.16% at 700 W) (P < 0.0001).     

后京都议定书时代的大都市:从手段到目的,从规划到激发

2008年,法国政府发起"后京都议定书时代大都市"和"未来都市巴黎"的研究,l'AUC事务所入选10家国际团队作为大巴黎研究项目的咨询顾问。本文展示了l'AUC事务所的方案及其他4个项目,分别针对当代规划、城市主义和建筑不同方面的主要问题:回收,生态城,紧凑和节点城市。     

Natural Ligands of Porcine Olfactory Binding Proteins

Knowledge of endogenous ligands of olfactory binding proteins is a prerequisite for studying their role in odor and pheromone transduction. Here, we report the extraction, derivatization, and characterization by gas chromatography-mass spectrometry of the natural ligands of pig, Sus scrofa (L.), Von Ebner’s Gland protein (VEG) and odorant binding protein (OBP). We identified two isoforms (VEG1 and VEG2), which differed only by the linkage of an O-N-acetylglucosamine (O-GlcNac) group on VEG1. The natural ligands of VEG1 were characterized as two isomers of testosterone, whereas ligands of VEG2 and OBP were fatty acids or their derivatives. Our findings suggest that the binding specificity of VEG1 for steroids is governed by the presence of an O-GlcNac moiety on the protein. This specificity was confirmed by the binding of radiolabeled testosterone only by VEG1 in an in-gel binding assay. This is the first evidence for a post-translational modification in the process of odorant discrimination by olfactory binding proteins.     

Growth and characterization of hydroxyapatite nanorice on TiO2 nanofibers

Hydroxyapatite (HA) coating with nanoparticles like nanorice is fabricated on chemically pretreated titanium (Ti) surface, through an electrochemical deposition approach, for biomaterial applications. The Ti surface was chemically patterned with anatase TiO₂ nanofibers. These nanofibers were prepared by in situ oxidation of Ti foils in a concentrated solution of H₂O₂ and NaOH, followed by proton exchange and calcinations. Afterward, TiO₂ nanofibers on Ti substrate were coated with HA nanoparticles like nanorice. The obtained samples were annealed at high temperature to produce inter diffusion between TiO₂ and HA layers. The resultant layers were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD), Infrared Spectroscopy (FTIR), corrosion tests in SBF solution, and Electron Probe Micro Analysis (EPMA). It was found that only Ti from the titanium substrate diffuses into the HA coating and a good corrosion resistance in simulated body fluid was obtained.     

On the performance of heterogeneous MANETs

Recent decades have witnessed the birth of major applications of wireless communication technology, further supported by the increasing capabilities of portable devices, low cost and ubiquitous presence. Despite radio technology diversity, a great deal of existing research focuses on a single and isolated wireless technology at a time, where homogeneous elements are identified by IP addresses. This work presents a heterogeneous technology routing (HTR) Framework, targeted towards scenarios where the heterogeneity of devices and networking technologies is present. Our contribution is many fold. It consists of a framework, which encompasses a process for bootstrapping networks, a routing protocol capable of dealing with multiple network interfaces, and a tuning with multipath extensions. We evaluate the performance of the bootstrap, routing and multipath mechanisms by way of simulation and an actual testbed implementation. The multipath evaluation simulates HTR networks with WiMAX, 3GPP LTE and Wi-Fi support. Results show that our proposal can effectively improve the data delivery ratio for ad-hoc networks and that it reduces the end-to-end delay without major impact on network energy consumption. As part of HTR tuning, we investigate next the impacts of tuning the HELLO refresh interval timer on route convergence and its subsequent energy consumption reduction during this phase. We also compare our tuned HTR with the widely used optimized link state routing protocol. Results show that varying the HELLO refresh interval can improve the convergence time and reduce the energy consumption without major impact on network behavior. Our proposal also includes a new distributed address allocation algorithm, namely, the dynamic node configuration protocol (DNCP). This paper conducts a comparative analysis between the Prime, Prophet and the DNCP schemes using static and dynamic topologies in terms of network setup time, energy consumption and control message overhead. Results show that the DNCP had a lower battery power consumption and less control message overhead while it slightly suffers with regard to setup.

     

LEIS for the prediction of turbulent multifluid flows applied to thermal-hydraulics applications

The paper centres on the use of the so-defined LEIS approach (Large-Eddy & Interface Simulation) for turbulent multifluid flows present in thermal-hydraulics applications. Interfacial flows involving deformable, sheared fronts separating immiscible fluids are shown to be within reach of this new approach, featuring direct resolution of turbulence and sheared interface deformations within the interface tracking (ITM) framework, such as level sets and VOF. In this technique supergrid turbulence and interfacial scales are directly solved whereas the sub-grid (SGS) parts are modelled, at least the turbulence part of it. First results are shown (feasibility), and difficulties and open issues are discussed. The connection between these two particular scales will also be discussed, and potential modelling routes evoked, including combining two-fluid and ITM, local grid refinement, or combing particle tracking and ITM for sub-grid inclusions smaller than the grid size.     

Robust H<Subscript>2</Subscript>-PSS design based on LQG control optimized by genetic algorithms

This paper proposes a genetic algorithms (GA) optimization technique applied to power system stabilizer (PSS) for adapt a robust H₂ control based on linear quadratic controller (LQ) and Kalman Filter applied on automatic excitation control of powerful synchronous generators, to improve stability and robustness of power system type single machine connected to an infinite bus system (SMIB). Adaptation technique proposed of the robust H₂ control with the various electrical and mechanical parametric variations based on the optimization of the PSS parameters. The genetic algorithms is a search technique based on the mechanisms of natural selection of a genetic and evolution. This optimization technique is more used in the field of control for solve optimal choice problem of regulators parameters. The integration of GA to robust H₂ control with robustness test (electrical and mechanical parameters variations of the synchronous machine) show considerable improvements in dynamics performances, robustness stability and good adaptation of the robust H₂-PSS parameters under uncertain constraints. This present study was performed using our realized Graphical User Interface (GUI) developed under MATLAB.     

Characterizations of friction welding joint interface for AISI 316

Because of heat amount is different from peripheral to central of friction welding interface, which is leaded to vary the characterizations along that interface. Current study, respectively, focused on the effect of different friction pressure on micro-structural and mechanical properties of that friction welding joint interface. Presently, these friction pressures are 110, 130, 150 and 170 MPa while kept all other conditions constant. The effects of different friction pressure on welding interface characterization were investigated by EDX, SEM, tensile, compression, impact and hardness tests. The tensile tests carried out on the standardized test piece with diameter 6 mm and 8 mm, thus, compression tests were extracted from the positions of 0°, 45° 90° with test specimen of 4 mm diameter and 6.5 mm length at weld center. Whereas, the impact test pieces were picked up in two positions, the first one is symmetrical, which it obtained to the respect of the rotation axis and the interface, on the other hand, the second one is non-symmetrical with the axis of rotation and symmetrical to the interface, for making the notch head coincide with the center of the welded joint, The obtained results showed that with reducing of friction pressure will present lack of bonding increasing from peripheral toward the welding center, which will responsible on reducing of the mechanical properties such as tensile, compression and impact strength.