A decision-directed adaptive gain equalizer for assistive hearing instruments

Assistive hearing instruments have a significant impact on speech enhancement when the signal-to-noise ratio is low. These instruments are usually developed using the conventional adaptive gain equalizer (AGE), which has low computational complexity and low distortion in real-time speech enhancement. The conventional AGEs are intended to boost the speech segments of speech signals but they are incapable of suppressing noise segments. The overall speech quality of the assistive hearing instruments may be reduced, as the noise segments still cannot be filtered out. In this paper, a decision-directed AGE is proposed for assistive hearing instruments. It aims to overcome the limitation of the conventional AGE, which is capable only of boosting speech segments in noisy speech but incapable of suppressing noise segments. The proposed approach simultaneously boosts the speech segments and suppresses noise segments in noisy speech. Experimental results with different types of real-world noise indicate that the proposed method achieves better speech quality than does the conventional AGE. The resulting method provides an improved functionality for assistive hearing instruments

Pyrene Mineralization by Mycobacterium sp. Strain KMS in a Barley Rhizosphere

To determine whether the soil Mycobacterium isolate KMS would mineralize pyrene under rhizosphere conditions, a microcosm system was established to collect radioactive carbon dioxide released from the labeled polycyclic aromatic hydrocarbon. Microcosms were designed as sealed, flow-through systems that allowed the growth of plants. Experiments were conducted to evaluate mineralization of 14C-labeled pyrene in a sand amended with the polycyclic aromatic hydrocarbons degrading Mycobacterium isolate KMS, barley plants, or barley plants with roots colonized by isolate KMS. Mineralization was quantified by collecting the 14CO2 produced from 14C-labeled pyrene at intervals during the 10-d incubation period. Roots and foliar tissues were examined for 14C incorporation. Mass balances for microcosms were determined through combustion of sand samples and collection and quantification of 14CO2 evolved from radiolabeled pyrene. No pyrene mineralization was observed in the sterile control systems. Greater release of 14CO2 was observed in the system with barley colonized by KMS than in microcosms containing just the bacterium inoculum or sterile barley plants. These findings suggest that phytostimulation of polycyclic aromatic hydrocarbons mineralization could be applied in remediation schemes

Effect of dietary organic zinc sources on growth performance, incidence of diarrhoea, serum and tissue zinc concentrations, and intestinal morphology in growing rabbits

[EN] This study was conducted to evaluate the effect of dietary organic zinc (Zn) sources on growth performance, the incidence of diarrhoea, serum and tissue Zn concentration, and intestinal morphology in growing rabbits. A total of 120 New Zealand White rabbits aged 35 d and with an initial body weight of 755±15 g, were randomly divided into 4 treatment groups for a 49 d feeding trial. Dietary treatments were designed with different Zn supplements as follows: (1) Control group: 80 mg/kg Zn as ZnSO4; (2) ZnLA group: 80 mg/kg Zn as Zn lactate; (3) ZnMet group: 80 mg/kg Zn as Zn methionine; (4) ZnGly group: 80 mg/kg Zn as Zn glycine. The results showed that, when compared with rabbits fed ZnSO4, supplementation with ZnLA improved (P4. Supplementing with ZnLA increased duodenum villi height (681.63 vs. 587.14 μm, P4, except that feeding ZnMet led to higher (P4. The results indicated that supplementation with 80 mg/kg Zn as ZnLA could improve growth performance, increase liver Zn concentration and enhance duodenum morphology, while reducing the incidence of diarrhoea in growing rabbits.Yan, J.; Zhang, G.; Zhang, C.; Tang, L.; Kuang, S. (2017). Effect of dietary organic zinc sources on growth performance, incidence of diarrhoea, serum and tissue zinc concentrations, and intestinal morphology in growing rabbits. World Rabbit Science. 25(1):43-49. doi:10.4995/wrs.2017.5770.SWORD434925

EGAM Induced by Energetic-electrons and Nonlinear Interactions among EGAM, BAEs and Tearing Modes in a Toroidal Plasma

In this letter, it is reported that the first experimental results are associated with the GAM induced by energetic electrons (eEGAM) in HL-2A Ohmic plasma. The energetic-electrons are generated by parallel electric fields during magnetic reconnection associated with tearing mode (TM). The eEGAM localizes in the core plasma, i.e. in the vicinity of q=2 surface, and is very different from one excited by the drift-wave turbulence in the edge plasma. The analysis indicated that the eEGAM is provided with the magnetic components, whose intensities depend on the poloidal angles, and its mode numbers are jm/nj=2/0. Further, there exist intense nonlinear interactions among eEGAM, BAEs and strong tearing modes (TMs). These new findings shed light on the underlying physics mechanism for the excitation of the low frequency (LF) Alfv\'enic and acoustic uctuations.Comment: 5 pages,4 figure

Effect of Parametric Resonances on the Bunched-beam Dilution Mechanism

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Limit Cycle Instability of Proton Beams Generated by Nonlinear Electron-Cooling Force

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Impact force identification with pseudo-inverse method on a lightweight structure for under-determined, even-determined and over-determined cases

Force identification using inverse technique is important especially when direct measurement through force transducer is not possible. Considering the effects of impact excitation force on the integrity of a lightweight structure, impact force identification has become the subject of several studies. A methodology utilising Operating Deflection Shape (ODS) analysis, Frequency Response Function (FRF) measurement and pseudo-inverse method to evaluate the dynamic force is presented. A rectangular plate with four ground supports was used as a test rig to simulate the motions of a simple vehicle body. By using the measured responses at remote points that are away from impact locations and measured FRFs of the test rig, unknown force locations and their time histories can be recovered by the proposed method. The performance of this approach in various cases such as under-determined, even-determined and over-determined cases was experimentally demonstrated. Good and bad combinations of response locations were selected based on the condition number of FRF matrix. This force identification method was examined under different response combinations and various numbers of response locations. It shows that in the over-determined case, good combination of response locations (i.e. low average of condition number of FRF matrix) and high number of response locations give the best accuracy of force identification result compared to under-determined and even-determined cases

Nonlinear Beam Dynamics Experiments: CE-22

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

The Beam Transfer Function Experiments: CE-37

This research was sponsored by the National Science Foundation Grant NSF PHY-931478