Graphene‐based ternary composites for supercapacitors

The research on electrode materials for supercapacitor application continues to evolve as the request of high‐energy storage system has increased globally due to the demand for energy consumption. Over the past decades, various types of carbon‐based materials have been employed as electrode materials for high‐performance supercapacitor application. Among them, graphene is 1 of the most widely used carbon‐based materials due to its excellent properties including high surface area and excellent conductivity. To exploit more of its interesting properties, graphene is tailored to produce graphene oxide and reduced graphene oxide to improve the dispersibility in water and easy to be incorporated with other materials to form binary composites or even ternary composites. Nowadays, ternary composites have attracted enormous interest as 2 materials (binary composites) cannot satisfy the requirement of the high‐performance supercapacitor. Thus, many approaches have been employed to fabricate ternary composites by combining 3 different types of electroactive materials for high‐performance supercapacitor application. This review focuses on the supercapacitive performance of graphene‐based ternary composites with different types of active materials, ie, conducting polymers, metal oxide, and other carbon‐based materials.     

Hybrid symbol- and bit-based source-controlled channel decoding for MELP speech parameters

A joint source channel coding (JSCC) scheme which exploits bit-level correlation as well as symbol-level correlation efficiently in a source-controlled channel decoding (SCCD) process is proposed and applied to the mixed-excitation linear prediction (MELP) parameters of speech. A modified BCJR algorithm is also proposed for use in the SCCD algorithm. Simulation results show that our proposed scheme performs better than other redundancy-based JSCC schemes such as bit-based SCCD, soft-bit speech decoding (SBSD) and iterative source-channel decoding.     

Electrochemical properties of free‐standing polypyrrole/graphene oxide/zinc oxide flexible supercapacitor

We report the preparation of a polypyrrole/graphene oxide/zinc oxide nanocomposite on a nickel foam using a simple and rapid single‐step electrochemical deposition process under ambient conditions. A free‐standing flexible supercapacitor was fabricated by sandwiching a polyvinyl alcohol hydrogel polymer electrolyte between two layers of the as‐prepared ternary nanocomposite electrodes. The electrochemical properties of the free‐standing supercapacitor were analyzed using a two‐electrode system. The supercapacitor achieved a specific capacitance of 123.8 F/g at 1 A/g, which was greater than its single (39.1 F/g) and binary (81.3 F/g) counterparts. This suggests that ZnO acts as a spacer and support that hinders the ternary structure from collapsing and subsequently enhances the diffusion of ions within the matrix. The flexible supercapacitor exhibited remarkable electrochemical stability when subjected to bending at various angles. The cycling stability of the ternary nanocomposite showed a favorable specific capacitance retention of more than 90% after 1000 cycles for mild alkaline electrolytes compared with strong alkali electrolytes. The presence of glycerin in the polymer electrolyte enabled the supercapacitor to perform better under the vigorous cycling condition. The potential of the as‐fabricated supercapacitor for real applications was manifested by its ability to light up a light‐emitting diode after being charged. Copyright © 2014 John Wiley & Sons, Ltd.     

Circle Chart for the Monitoring of Maxima in Periodic Processes

An important process characteristic is process maxima as it is often an important quality or performance parameter. Such measurements often play a vital role in process analysis and have to be monitored carefully. In this paper, we consider the problem of monitoring process maxima when the process exhibits a kind of periodicity. A circle chart for periodical process maxima with or without seasonal patterns monitoring is developed and studied, by modeling the process maxima using the extreme value distribution. Mean normalization is applied for periodic process monitoring with seasonal patterns to facilitate comparison between different sections and periods. The average cycle run length is proposed to measure charting efficiency. Copyright © 2014 John Wiley & Sons, Ltd.     

Improved Bit-Based Joint Source-Channel Decoding of Variable Length Codes

Joint source channel decoding (JSCD) for variable length codes (VLCs) has been shown to be effective for error- prone channels. In this paper, we propose two schemes to enhance the performance of the existing bit-based JSCD approach for VLCs. Simulation results show that the performance of the decoder can be significantly improved, while the computational complexity is only slightly increased by using our proposed schemes.     

Genetic and enological analysis of selected Saccharomyces cerevisiae strains for wine production

The non‐wine Saccharomyces cerevisiae strain of 96581 was found to be a promising candidate for the production of white wine. It produced wines with fusel alcohols that were 57% higher than those produced by the wine yeasts studied and was also more efficient in the production of 2‐phenethyl acetate and 3‐methyl‐1‐butanol acetate. This study also shows that there is a difference in the ester‐formation efficiency for acetates relative to C6, C8 and C10 fatty acid esters for all the studied yeast strains. Therefore, it supports the view that other unidentified enzymes besides those regulated by ATF1 and ATF2 genes are involved in the production of ethyl esters of C6–C10 fatty acids. DNA analysis of the 25S, 18S, 5.8S and 5S ribosomal DNA genes in these strains showed high conservation. Despite the closely related nature of these yeast strains, the chemical profiles of the wines produced were significantly different.     

Inlaying nanoscale surface recess patterns with nanoscale objects

A simple and versatile approach to constructing patterns on a solid surface using nanoscale objects is demonstrated. The approach is essentially an inlaying process, in which recess patterns fabricated on a surface are selectively filled with nanoscale objects. The objects are anchored firmly on the surface due to the spatial confinement provided by the recess structures. Protein molecules and inorganic nanoparticles are used in this demonstration. Cyclic voltammetry is used to detect electron transfer signals from patterns of protein molecules. The approach suggests a potentially fast, high-throughput and versatile technique for constructing architectural structures on a solid surface using nanoscale objects.     

城市交响曲 2010年上海世博会新加坡馆

2010上海世博会新加坡馆以＂城市交响曲＂为主题,呈现了岛国多元文化的融洽与和谐,以及花园城市可持续发展的美好生活。     

Speech enhancement based on hybrid algorithm

A hybrid algorithm that incorporates the minimum mean square error (MMSE) algorithm and the auditory masking algorithm for speech enhancement is proposed. The proposed algorithm results in a significant reduction in residual noise compared with that in the enhanced speech produced by the MMSE algorithm alone