The slot-coupled hemispherical dielectric resonator antenna with a parasitic patch: applications to the circularly polarized antenna and wide-band antenna

The aperture-coupled hemispherical dielectric resonator antenna (DRA) with a parasitic patch is studied rigorously. Using the Green's function approach, integral equations for the unknown patch and slot currents are formulated and solved using the method of moments. The theory is utilized to design a circularly polarized (CP) DRA and a wide-band linearly polarized (LP) DRA. In the former, the CP frequency and axial ratio (AR) can easily be controlled by the patch location and patch size, respectively, with the impedance matched by varying the slot length and microstrip stub length. It is important that the AR will not be affected when the input impedance is tuned, and the CP design is therefore greatly facilitated. For the wide-band LP antenna, a maximum bandwidth of 22% can be obtained, which is much wider than the previous bandwidth of 7.5% with no parasitic patches. Finally, the frequency-tuning characteristics of the proposed antenna are discussed. Since the parasitic patch can be applied to any DRAs, the method will find applications in practical DRA designs.     

Synthesis and self-association in aqueous media of poly(ethylene oxide)/poly(ethyl glycidyl carbamate) amphiphilic block copolymers

New temperature sensitive AB, ABA, and BAB amphiphilic block copolymers consisting of hydrophilic poly(ethylene oxide) and hydrophobic poly(ethyl glycidyl carbamate) blocks were synthesized by anionic polymerization followed by chemical modification reactions. The self-association of the block copolymers in aqueous media was studied by UV-vis spectroscopy and dynamic and static light scattering. The obtained block copolymers spontaneously form micelles in aqueous media. The critical micellization concentration varied from 0.5 to 4 g/L depending on the copolymer architecture and composition. The influence of the temperature upon the self-association of the block copolymers was investigated. The increase of temperature did not affect the value of the critical micellization concentration, but led to the formation of better defined micelles with narrow size distribution.     

Prolonged degradation of end-capped polyelectrolyte multilayer films

Cationic chitosan (CT) and anionic dextran sulfate (Dex) were layer-by-layer (LbL) assembled from aqueous solutions containing 1 M NaCl on a quartz crystal microbalance (QCM) substrate, and the original films ((CT-Dex)₃-CT)) were end-capped with LbL assembly from CT solutions containing 1 M NaCl and Dex solutions without NaCl. The enzymatic degradation of films by chitosanase was quantitatively analyzed by QCM in terms of numbers of end-capping steps. The degradation of films end-capped with (Dex-CT)₃ was considerably prolonged when compared to those end-capped with other end-capping steps. A mechanism for the prolonged degradation was proposed by quantitative QCM data and zeta potential results.     

Syngas production by biomass gasification using Rh/CeO2/SiO2 catalysts and fluidized bed reactor

We have been developed novel catalysts for gasification of biomass with much higher energy efficiency than conventional methods (non-catalyst, dolomite, commercial steam reforming Ni catalyst). From the result of the gasification of cellulose over novel Rh/CeO₂/SiO₂ catalysts, it is found that the gasification process consists of the reforming of tar and the combustion of solid carbon. We also tested novel Rh/CeO₂/SiO₂ in the gasification with air, pyrogasification, and steam reforming of cedar wood. As a result, Rh/CeO₂/SiO₂ gave higher yield of syngas than the conventional steam reforming Ni catalyst. Furthermore, we compared the performance between single and dual bed reactors. Single bed reactor was effective in the gasification of cedar, however, it was not suitable for the gasification of rice straw since a rapid deactivation was observed. Gasification of rice straw, jute stick, baggase using the fluidized dual-bed reactor and Rh/CeO₂/SiO₂ was also investigated. Especially, the catalyst stability in the gasification of rice straw clearly was enhanced by using the fluidized dual bed reactor.     

Resistance to sulfur poisoning of hot gas cleaning catalysts for the removal of tar from the pyrolysis of cedar wood

In the partial oxidation of tar derived from the pyrolysis of cedar wood, the effect of H₂S addition was investigated over non-catalyst, steam reforming Ni catalyst, and Rh/CeO₂/SiO₂ using a fluidized bed reactor. In the non-catalytic gasification, the product distribution was not influenced by the presence of H₂S. Steam reforming Ni catalyst was effective for the tar removal without H₂S addition, however, the addition of H₂S deactivated drastically. In contrast, Rh/CeO₂/SiO₂ exhibited higher and more stable activity than the Ni catalyst even under the presence of high concentration of H₂S (280 ppm). On the Ni catalyst, the adsorption of sulfur was observed by XPS and Ni species was oxidized during the partial oxidation of tar. In the case of Rh/CeO₂/SiO₂, the adsorption of sulfur was below the detection limit of XPS. This can be related to the self-cleaning of catalyst surface during the circulation in the fluidized bed reactor for the partial oxidation of tar derived from cedar pyrolysis.     

Catalyst Design of Pt-Modified Ni/Al2O3 Catalyst with Flat Temperature Profile in Methane Reforming with CO2 and O2

Pt(0.3)/Ni(10)/Al₂O₃, prepared by a sequential impregnation method, exhibited a more excellent performance in methane reforming with CO₂ and O₂ in terms of the catalytic activity and the temperature profile of the catalyst bed than Pt(0.3) + Ni(10)/Al₂O₃ prepared by a coimpregnation method, Ni(10)/Al₂O₃, Pt(0.3)/Al₂O₃, and Pt(10)/Al₂O₃. It is thought that this is because the surface Pt atoms on Ni catalyst can contribute to the enhancement of the catalyst reducibility.     

High quality voice conversion using prosodic and high-resolution spectral features

Voice conversion methods have advanced rapidly over the last decade. Studies have shown that speaker characteristics are captured by spectral feature as well as various prosodic features. Most existing conversion methods focus on the spectral feature as it directly represents the timbre characteristics, while some conversion methods have focused only on the prosodic feature represented by the fundamental frequency. In this paper, a comprehensive framework using deep neural networks to convert both timbre and prosodic features is proposed. The timbre feature is represented by a high-resolution spectral feature. The prosodic features include F0, intensity and duration. It is well known that DNN is useful as a tool to model high-dimensional features. In this work, we show that DNN initialized by our proposed autoencoder pretraining yields good quality DNN conversion models. This pretraining is tailor-made for voice conversion and leverages on autoencoder to capture the generic spectral shape of source speech. Additionally, our framework uses segmental DNN models to capture the evolution of the prosodic features over time. To reconstruct the converted speech, the spectral feature produced by the DNN model is combined with the three prosodic features produced by the DNN segmental models. Our experimental results show that the application of both prosodic and high-resolution spectral features leads to quality converted speech as measured by objective evaluation and subjective listening tests.     

The tauola-photos-F environment for the TAUOLA and PHOTOS packages, release II

We present the system for maintaining the versions of two packages: the TAUOLA of τ-lepton decay and PHOTOS for radiative corrections in decays. The following features can be chosen in an automatic or semi-automatic way: (1) format of the common block HEPEVT; (2) version of the physics input (for TAUOLA): as published, as initialized by the CLEO collaboration, as initialized by the ALEPH collaboration (it is suggested to use this version only with the help of the collaboration advice), new optional parametrization of matrix elements in 4π decay channels; (3) type of application: stand-alone, universal interface based on the information stored in the HEPEVT common block including longitudinal spin effects in the elementary Z/γ^∗→τ⁺τ⁻ process, extended version of the standard universal interface including full spin effects in the H/A→τ⁺τ⁻ decay, interface for KKMC Monte Carlo, (4) random number generators; (5) compiler options. The last section of the paper contains documentation of the programs updates introduced over the last two years.

Program summary

Title of program:tauola-photos-F, release IICatalogue identifier:ADXO_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXO_v1_0Programs obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandComputer: PC running GNU/Linux operating systemProgramming languages and tools used:CPP: standard C-language preprocessor, GNU Make builder tool, also FORTRAN compilerNo. of lines in distributed program, including test data, etc.: 194 118No. of bytes in distributed program, including test data, etc.:2 481 234Distribution format: tar.gzCatalogue identifier:ADXO_v2_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXO_v2_0No. of lines in distributed program, including test data, etc.:308 235No. of bytes in distributed program, including test data, etc.:2 988 363Distribution format:tar.gzDoes the new version supersede the previous version:YesNature of the physical problem: The code of Monte Carlo generators often has to be tuned to the needs of large HEP Collaborations and experiments. Usually, these modifications do not introduce important changes in the algorithm, but rather modify the initialization and form of the hadronic current in τ decays. The format of the event record (HEPEVT common block) used to exchange information between building blocks of Monte Carlo systems often needs modification. Thus, there is a need to maintain various, slightly modified versions of the same code. The package presented here allows the production of ready-to-compile versions of TAUOLA [S. Jadach, Z. Wa?s, R. Decker, J.H. Kühn, Comput. Phys. Comm. 76 (1993) 361; A.E. Bondar, et al., Comput. Phys. Comm. 146 (2002) 139] and PHOTOS [E. Barberio, Z. Wa?s, Comput. Phys. Comm. 79 (1994) 291] Monte Carlo generators with appropriate demonstration programs. The new algorithm, universal interface of TAUOLA to work with the HEPEVT common block, is also documented here. Finally, minor technical improvements of TAUOLA and PHOTOS are also listed.Method of solution: The standard UNIX tool: the C-language preprocessor is used to produce a ready-to-distribute version of TAUOLA and PHOTOS code. The final FORTRAN code is produced from the library of ‘pre-code’ that is included in the package.Reasons for new version: The functionality of the version of TAUOLA and PHOTOS changed over the last two years. The changes, and their reasons, are documented in Section 9, and our new papers cited in this section.Additional comments: The updated version includes new features described in Section 9 of the paper. PHOTOS and TAUOLA were first submitted to the library as separate programs. Summary details of these previous programs are obtainable from the CPC Program Library.Typical running time: Depends on the speed of the computer used and the demonstration program chosen. Typically a few seconds.     

维吾尔语广播新闻连续语音敏感词检索系统

首先介绍语音信号来源于新疆人民广播电台维吾尔语新闻的敏感词语音语料库的建设。然后用该语料库进行基于HMM的模型训练。模型训练中详细介绍识别基元端点检测、特征提取、矢量量化、码本构建、HMM模型训练过程和结果。最后用该语料库和HMM训练模型对维吾尔语广播新闻连续语音信号进行敏感词检索,并对检索结果进行分析。