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Sol-gel method was used by taking tetraethyl orthosilicate (TEOS) as precursor, ethanol (C 2 H 5 OH) as solvent and hydrochloric acid (HCl) as catalyst, 1-γ-methacryloxypropyl trimethoxysilane (KH570) as a coupling agent for preparations of SiO 2 , KH570 and 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO, flame retardant) sols to improve flame retardancy and thermal stability of cotton fabrics. Dipping-baking process was used for finishing cotton fabrics. Surface morphology, surface functional group and element distribution, intrinsic crystal structure, pyrolysis characteristics and flame retardancy of cotton fabrics were characterized by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TG), and limiting oxygen index (LOI). Results show that DOPO and SiO 2 sol have good synergistic flame retardant effect. Cotton fabric finished by hybrid sol of SiO 2 -KH570-DOPO has the best flame retardant effect, its LOI is 22.8 %, ΔLOI/Δm is 4.20 %/g. DOPO-contained hybrid sol can promote formation of three-dimensional microscopic gel coating and residual char in condensed phase.

Based on vertical alliance, we proposed quantity competition models by two competing manufacturers and one dominated retailer. Compared with wholesale price contract, we investigated the valid mechanism for vertical alliances formation and the range of revenue sharing contract, and also we analyzed the impact of product competition and price risk on the choice of alliances and revenue sharing contract. The results suggest that the alliances are dependent on the intensity of product competition rather than price risk. However, the proportion range for retailer revenue sharing contract based on the alliances will increase with product competition intensity. Manufacturers will not discard the alliance voluntarily. Under a single vertical alliance, manufacturers and retailers will never drop out of the vertical alliance no matter how to change the intensity of competition. In other words, with more manufacturers coming into the competition, there must be one manufacturer and retailer can form a vertical alliance. However, under more vertical alliances, the manufacturers will never drop out of the vertical alliances no matter how to change the intensity of competition. However, with the increase of products competition intensity, the two vertical alliances will collapse to a single vertical alliance, and the collapse is only related to the retailer.

As one important part of Internet of Things (IoT), wireless body area networks (WBANs) get rapid development in recent years. The majority of current WBAN researchers focus on the radio frequency (RF) solutions. However, there are still some intrinsic defects in the RF-based WBANs. Recently, human body communication (HBC) has been proposed in which the body itself is used as the propagation medium. To achieve high spectrum efficiency and power efficiency by HBC, one critical work is to acquire the channel information. In this paper, the HBC channel fading characteristics are measured and summarized. It is shown that the HBC channel is influenced by the body shape instead of the outside environment. When human body is in movement, normal random process can be used to describe the variations of HBC channel fading. Then, we propose a dynamic pilot interval adjustment scheme for HBC channel estimation. By applying this scheme, the pilot intervals in time domain can be adjusted along with the time-varying channel fading. The performance of the proposed scheme is evaluated by using measurement-based HBC channel fading model. It is proved that this scheme can substantially reduce the number of pilots without losing much accuracy and it can be beneficial for saving energy in the HBC networks.

Global emergency mobile communication system proposed in this paper can accomplish realtime call and text message communication based on TDRSS. It can be applied to ocean sailing, disaster relief, landing ground searching. System constructure and operational mode are designed. The design scheme of the mobile terminal is also proposed in this paper. Multi-user capacity is analyzed through calculation and simulation.

The textile and apparel product is old textile apparel. The paper first analyzed the basic decision model of supply chain considering only carbon tax circumstances. Then, on this basis, the paper explored the supply chain optimal production and ordering decision considering government recycling and technology upgrading subsidy policy respectively, through designing the utilization rate of recycled products and the reduction rate of carbon emissions after technical transformation. Finally combined two kinds of subsidies policies, the optimal decision of supply chain was discussed. The results show that the only carbon tax policy may play a role in reducing carbon emissions, but for textile and apparel industry which the profit margin is small, it may decrease the benefit of company. As a result, the combination of government recycling and technology upgrading subsidy policy will realize the both objective of carbon emission reduction and economic benefits for apparel supply chain.

In the pseudo-target dynamic feasible region constraint method,which aims at locating the target using single observer in NLOS environment, the area of the target feasible region has direct effect on the speed and accuracy of the location algorithm. An optimal path planning algorithm of the observer is proposed in this paper, which is based on the dynamic programming. Based on the data measured at the current stage, the optimal moving direction of the observer at the next stage is calculated aiming at the maximum area of the target feasible region convergence. The optimized maneuvering path calculated by the proposed algorithm can improve the location precision and reduce the location time.

A location and tracking method utilizing extended Kalman filter (EKF) using single base station in cellular networks is proposed in this paper. The location method utilizing the AOA and the variance ratio of AOA is introduced. The paper also compares EKF and linear Kalman filter. The simulation result is illustrated to explain the location and tracking efficiency of the proposed method.