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Frame mold is the key tool for autoclave processing of composite structures. Its stiffness and temperature uniformity have important influences on the quality, particularly the synchronization of curing of the processed composite structures. In this paper, a novel topology optimization method is proposed to design the frame mold for improving the stiffness and the temperature uniformity while reducing the weight. A computational fluid dynamics (CFD) model is developed to analyze the temperature field of the frame mold during the curing process and its accuracy is validated by experiment. Furthermore, the original mold and optimized mold covered with the composite panel are introduced to the numerical model to research the evolution process of the degree of cure (DoC) during a curing cycle. The results show that the overall structure weight of the optimized mold is reduced by 16.04%, the stiffness is increased by 27%, and the temperature uniformity is increased by 29%. The synchronization of curing of the composite panel is also improved by 26.7% using the optimized mold. [ABSTRACT FROM AUTHOR]

Haze scatters light transmitted in the air and reduces the visibility of images. Dealing with haze is still a challenge for image processing applications nowadays. For the purpose of haze removal, we propose an accelerated dehazing method based on single pixels. Unlike other methods based on regions, our method estimates the transmission map and atmospheric light for each pixel independently, so that all parameters can be evaluated in one traverse, which is a key to acceleration. Then, the transmission map is bilaterally filtered to restore the relationship between pixels. After restoration via the linear hazy model, the restored images are tuned to improve the contrast, value, and saturation, in particular to offset the intensity errors in different channels caused by the corresponding wavelengths. The experimental results demonstrate that the proposed dehazing method outperforms the state-of-the-art dehazing methods in terms of processing speed. Comparisons with other dehazing methods and quantitative criteria (peak signal-to-noise ratio, detectable marginal rate, and information entropy difference) are introduced to verify its performance. [ABSTRACT FROM AUTHOR]

In the study, the (Ni0.6Co0.1Mn0.2Fe0.1)C2O4 precursor was synthesized according to the oxalate co-precipitation method under different pH values and then layered Ni-rich LiNi0.6Co0.1Mn0.2Fe0.1O2 (6121) materials were prepared by calcinating the mixture of oxalate precursor and LiOH·H2O in an oxygen atmosphere. The crystal structure, morphology, chemical compositions, and electrochemical behaviors of the tetrad cathode materials were explored respectively by XRD, SEM, HRTEM, EDS, and electrochemical charge-discharge tests. The XRD results revealed that the ratios of c/a and I(003)/I(104) respectively increased from 4.989 to 1.47 to 5.000 and 1.61 after Fe substituted Co in LiNi0.6Co0.2Mn0.2O2 (622). SEM images showed that spherical particles were more uniform and that the particle diameter decreased from 15 µm to 10 µm after the introduction of Fe. The results of charge/discharge tests indicated that the LiNi0.6Co0.1Mn0.2Fe0.1O2 sample had the lower polarization (10% at 0.1 C), the higher cycling retention (86% after 100 cycles at 1 C), and the enhanced rate performance. The LiNi0.6Co0.1Mn0.2Fe0.1O2 sample showed the better reversibility, smaller impedance parameters and a larger Li+ diffusion coefficient in CV and EIS analyses. This study provides a promising tetrad cathode material with the better crystal structure, higher columbic efficiency and better cycle performance. The new tetrad cathode material is expected to become part and parcel of cathode materials. [ABSTRACT FROM AUTHOR]

Heat shock protein 60 (HSP60) is a highly conserved chaperone molecule that plays important roles in mediating some physiological and pathological functions. However, researchers have not yet determined whether HSP60 is expressed in the mammalian cochlea. This study constitutes the first investigation of the expression of HSP60 in the postnatal rat cochlea. We also examined the expression of HSP60 in rats with drug-induced hearing loss. Auditory thresholds were assessed by monitoring the auditory brainstem response (ABR) prior to and after drug injection. Expression levels of the HSP60 gene (Hsp60) and HSP60 protein in the rat cochlea were detected by quantitative real-time polymerase chain reaction and Western blotting, respectively. The distribution of HSP60 in the rat cochlea was further examined by immunofluorescence staining. We have demonstrated that HSP60 was expressed in the postnatal rat cochlea in an age-dependent and cell-specific manner. In addition, after drug exposure, the average hearing threshold of rats in the experimental group was significantly higher than that in the control group, with increased HSP60 expression level in response to kanamycin and furosemide treatments. HSP60 expression was observed in the supporting cells (SCs) within the organ of Corti in both the uninjured and the injured cochlea, but it was undetectable in the mechanosensory hair cells (HCs) and spiral ganglion neurons. Therefore, our research suggests that HSP60 may play an important role in auditory function. [ABSTRACT FROM AUTHOR]

Porous carbon nanosheets (PCNSs), porous carbon nanofibers (PCNFs), and flowerlike porous carbon microspheres (FPCMs) were successfully synthesized through a carbonization method combined with a simple acid pickling treatment using calcium citrate as the precursor. The as-prepared products show uniform morphologies, in which the FPCMs are self-assembled from PCNSs. As anodes of lithium-ion (Li-ion) batteries, these carbon materials deliver a stable reversible capacity above 515 mAh g after 50 cycles at 100 mA g. Compared with PCNSs and PCNFs, FPCMs demonstrate preferable rate capability (378 mAh g at 1 A g) and cyclability (643 mAh g at 100 mA g). These results suggest that an appropriate select of morphology and structure will significantly improve the lithium storage capacity. The study also indicates that the novel shape-controlled porous carbon materials have potential applications as electrode materials in electronic devices. [ABSTRACT FROM AUTHOR]

For the accurate description of aerodynamic characteristics for aircraft, a wavelet neural network (WNN) aerodynamic modeling method from flight data, based on improved particle swarm optimization (PSO) algorithm with information sharing strategy and velocity disturbance operator, is proposed. In improved PSO algorithm, an information sharing strategy is used to avoid the premature convergence as much as possible; the velocity disturbance operator is adopted to jump out of this position once falling into the premature convergence. Simulations on lateral and longitudinal aerodynamic modeling for ATTAS (advanced technologies testing aircraft system) indicate that the proposed method can achieve the accuracy improvement of an order of magnitude compared with SPSO-WNN, and can converge to a satisfactory precision by only 60-120 iterations in contrast to SPSO-WNN with 6 times precocities in 200 times repetitive experiments using Morlet and Mexican hat wavelet functions. Furthermore, it is proved that the proposed method is feasible and effective for aerodynamic modeling from flight data. [ABSTRACT FROM AUTHOR]

In order to accurately describe the dynamic characteristics of flight vehicles through aerodynamic modeling, an adaptive wavelet neural network (AWNN) aerodynamic modeling method is proposed, based on subset kernel principal components analysis (SKPCA) feature extraction. Firstly, by fuzzy C-means clustering, some samples are selected from the training sample set to constitute a sample subset. Then, the obtained samples subset is used to execute SKPCA for extracting basic features of the training samples. Finally, using the extracted basic features, the AWNN aerodynamic model is established. The experimental results show that, in 50 times repetitive modeling, the modeling ability of the method proposed is better than that of other six methods. It only needs about half the modeling time of KPCA-AWNN under a close prediction accuracy, and can easily determine the model parameters. This enables it to be effective and feasible to construct the aerodynamic modeling for flight vehicles. [ABSTRACT FROM AUTHOR]

The formation of covalently linked composites of multi–walled carbon nanotubes (MWCNT) and glucose oxidase (GOD) with high-function density for use as a biosensing interface is described. The reaction intermediates and the final product were characterized by using FT–IR spectroscopy, and the MWCNT-coated GOD nanocomposites were examined by atomic force microscopy (AFM) and transmission electron microscopy (TEM). Interestingly, it was found that the GOD–MWCNT composites are highly water soluble. Electrochemical characterization of the GOD–MWCNT composites that were modified on a glassy carbon electrode shows that the covalently linked GOD retains its bioactivity and can specifically catalyze the oxidation of glucose. The oxidation current shows a linear dependence on the glucose concentration in the solution in the range of 0.5–40 mM with a detection limit of 30 μM and a detection sensitivity of 11.3 μA/mMcm2. The present method may provide a way to synthesize MWCNT related composites with other biomolecules and for the construction of enzymatic reaction-based biofuel cells and biosensors. [ABSTRACT FROM AUTHOR]