Speech Separation Methodology for Hearing Aid

In the design of hearing aids (HA), the real-time speech-enhancement is done. The digital hearing aids should provide high signal-to-noise ratio, gain improvement and should eliminate feedback. In generic hearing aids the performance towards different frequencies varies and non uniform. Existing noise cancellation and speech separation methods drops the voice magnitude under the noise environment. The performance of the HA for frequency response is non uniform. Existing noise suppression methods reduce the required signal strength also. So, the performance of uniform sub band analysis is poor when hearing aid is concern. In this paper, a speech separation method using Non-negative Matrix Factorization (NMF) algorithm is proposed for wavelet decomposition. The Proposed non-uniform filter-bank was validated by parameters like band power, Signal-to-noise ratio (SNR), Mean Square Error (MSE), Signal to Noise and Distortion Ratio (SINAD), Spurious-free dynamic range (SFDR), error and time. The speech recordings before and after separation was evaluated for quality using objective speech quality measures International Telecommunication Union -Telecommunication standard ITU-T P.862.     

改造FK501型绢纺细纱机、纺制苎麻纱的生产实践

针对FK501型绢纺细纱机的设备工艺特性，参照FZ501、DJ562C(Z)麻纺细纱机，对FK501型绢纺细纱机原机牵伸装置，牵伸传动、捻度、卷绕成形系统进行了适当的改造，使之成功地用于苎麻纺纱生产。     

双动技术在高压SF6断路器中的应用

介绍了双动技术的原理,分析了采用双动技术的AREVA公司GL312型SF6断路器及其配套的FK3-X系列弹簧操作机构的技术优点。     

线性时差校正技术在噪音压制中的应用

对于一个横向、纵向偏移距比较大的三维地震数据而言,折射波等噪音的线性形态会随着横向偏移距的加大而向着双曲线形态变化。当炮点位于某检波点线附近,横向偏移距较小的情况下,该检波线接收到的线性噪音在地震记录上呈线性状态分布;当炮点远离排列,横向偏移距比较大时,该排列单炮上的线性噪音则呈双曲线形态,并且随着横向偏移距的加大双曲现象就越明显。常规FK滤波等压制线性噪音的方法,对于这种由于横向偏移距增大而引起的非线性噪音其压制能力较差。笔者采用线性时差校正的方法,首先将横向偏移距对线性噪音旅行时的影响消除掉,恢复其线性形态,再应用线性噪音压制技术将其压制掉,最后进行反线性时差校正,以达到高精度噪音压制的目的。目前这种方法在宽方位角采集的数据上取得比较好的效果。      

Synthesis and biological evaluation of isosteric analogues of FK866, an inhibitor of NAD salvage

One of the great challenges of medicinal chemistry is to create novel, effective, chemotherapeutic agents that show specificity for cancer cells combined with low systemic toxicity. A novel idea is to target the enzymes of the NAD biosynthesis and recycling pathways given that cancer cells display a higher NAD turnover rate than healthy cells. To this end, the compound FK866 (APO866; (E)-N-[4-(1-benzoylpiperidin-4-yl) butyl]-3-(pyridin-3-yl) acrylamide), which blocks nicotinamide phosphoribosyltransferase (NMPRTase) has entered clinical trials as a potential chemotherapeutic agent. Here we report the synthesis of analogues of FK866 synthesized by click chemistry.     

基于ADSP-BF506的异步电动机矢量控制系统研究

采用ADSP-BF506作为控制器设计了一双闭环矢量控制控制系统,实现对三相交流电动机的速度控制。介绍了矢量控制原理,给出系统构成及软件流程图。实验证明,该系统具有良好的动态特性,控制精度高,达到了实时控制要求。     

Fenton-Chemistry-Based Oxidative Modification of Proteins Reflects Their Conformation

In order to understand protein structure to a sufficient extent for, e.g., drug discovery, no single technique can provide satisfactory information on both the lowest-energy conformation and on dynamic changes over time (the ‘four-dimensional’ protein structure). Instead, a combination of complementary techniques is required. Mass spectrometry methods have shown promise in addressing protein dynamics, but often rely on the use of high-end commercial or custom instruments. Here, we apply well-established chemistry to conformation-sensitive oxidative protein labelling on a timescale of a few seconds, followed by analysis through a routine protein analysis workflow. For a set of model proteins, we show that site selectivity of labelling can indeed be rationalised in terms of known structural information, and that conformational changes induced by ligand binding are reflected in the modification pattern. In addition to conventional bottom-up analysis, further insights are obtained from intact mass measurement and native mass spectrometry. We believe that this method will provide a valuable and robust addition to the ‘toolbox’ of mass spectrometry researchers studying higher-order protein structure.     

基于TSIC506的高精度温度检测系统的设计

以ATmega16单片机为控制核心,利用数字化温度传感器TSIC506实现高精度温度检测系统。论述了该系统的硬件组成和软件设计,给出了系统总体结构及相应的ATmega16单片机温度测量程序。实际应用表明,该温度检测系统具有结构简单、成本低、稳定实用等特点,可根据不同需要应用于多种工农业温度检测领域。     

The impact of programming methodology on program complexity

The rising demand and cost of software have prompted researchers to investigate factors associated with program changes in software systems. Numerous program complexity measures and statistical techniques have been used to study the effects of program complexity on program changes. The effects of programming methodology on the relationship of complexity to program changes were measured in this study. The results suggest that the relationship of length and structure complexity characteristics to program changes is consistent for different programming methodologies, while the relationship of program changes and characteristics that relate to the use of data and procedure names is not consistent for different programming methodologies.     

FK506-binding protein mutational analysis: defining the active-site residue contributions to catalysis and the stability of ligand complexes

The 12 kDa FK506-binding protein FKBP12 is a cis-trans peptidyl-prolylisomerase that binds the macrolides FK506 and rapamycin. Wehave examined the role of the binding pocket residues of FKBP12in protein–ligand interactions by making conservativesubstitutions of 12 of these residues by site-directed mutagenesis.For each mutant FKBP12, we measured the affinity for FK506 andrapamycin and the catalytic efficiency in the cis–transpeptidyl-prolyl isomerase reaction. The mutation of Trp59 orPhe99 generates an FKBP12 with a significantly lower affinityfor FK506 than wild-type protein. Tyr26 and Tyr82 mutants areenzymatically active, demonstrating that hydrogen bonding bythese residues is not required for catalysis of the cis–transpeptidyl-prolyl isomerase reaction, although these mutationsalter the substrate specificity of the enzyme. We conclude thathydrophobic interactions in the active site dominate in thestabilization of FKBP12 binding to macrolide ligands and tothe twisted-amide peptidyl-prolyl substrate intermediate.