Different mulches have variable effects on soil physical properties and plant growth. This study aimed to compare the effects of mulching with inorganic (round gravel, RG), organic (wood chips, WC), and living (manila turf grass, MG) materials on soil properties at 0–5-cm and 5–10-cm depths, as well as on the growth and physiological features of Osmanthus fragrans L. ‘Rixianggui’ plants. Soil samples were collected at three different time points from field plots of O. fragrans plants treated with the different mulching treatments. Moisture at both soil depths was significantly higher after mulching with RG and WC than that in the unmulched control (CK) treatment. Mulching did not affect soil bulk density, pH, or total nitrogen content, but consistently improved soil organic matter. The available nitrogen in the soil increased after RG and WC treatments, but decreased after MG treatment during the experimental period. Mulching improved plant growth by increasing root activity, soluble sugar, and chlorophyll a content, as well as by providing suitable moisture conditions and nutrients in the root zone. Plant height and trunk diameter were remarkably increased after mulching, especially with RG and WC. However, while MG improved plant growth at the beginning of the treatment, the ‘Rixianggui’ plants later showed no improvement in growth. This was probably because MG competed with the plants for water and available nitrogen in the soil. Thus, our findings suggest that RG and WC, but not MG, improved the soil environment and the growth of ‘Rixianggui’ plants. Considering the effect of mulching on soil properties and plant growth and physiology, round gravel and wood chips appear to be a better choice than manila turf grass in ‘Rixianggui’ nurseries. Further studies are required to determine the effects of mulch quality and mulch-layer thickness on shoot and root growths.

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Few-mode fiber (FMF) based mode division multiplexing (MDM) transmission system has been considered as a potential candidate for future backbone network, unfortunately, the mode-dependent loss (MDL) in MDM system remains to be a tough issue in high speed transmission application. Recently, the optimal maximum-likelihood (ML) detection has demonstrated its potential ability and efficiency in suppressing the capacity-limiting MDL. However, this ML detector employed at the receiver of MDM system achieves the optimal performance at the sacrifice of the exponential growth in complexity. Inspired by the fact that probabilistic data association (PDA) is able to offer near-ML performance without introducing the enormous computational complexity, in this paper, a soft-decision aided PDA detector is proposed for MDM system detection, in which the probabilities of the potential candidate symbols are iteratively estimated by using the approximation of the Bayesian theorem. In addition, only those high reliability symbols are detected to save the computational effort. To validate the proposed scheme, both weakly and strongly coupled modes have been considered. Simulation results show that the proposed PDA based detector can achieve a flexible trade-off between the BER performance and the computational complexity when compared with the optimal ML detection in FMF-based MDM system. INDEX TERMS Complexity, mode division multiplexing, mode-dependent loss, probabilistic data association.

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Under high temperature conditions, polyethylene particles are dissolved in xylene in a flask reactor, and organic molecules such as peroxymethylenetetraimide and tetramethylbenzoquinone dimethyl methane with different concentrations are added to the mixture. At 150 ℃, the sample is hot pressed into a thin film. The characteristics of DC decomposing power as well as room charge distribution were measured. The experimental results show that doping small molecules can not only effectively restrain the gathering of room charge, but also enhance the DC decomposing power. Doped small molecules can introduce deep wells to capture space charges and disperse carriers, thereby reducing the number, mobility and energy of carriers.