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An array-point-raft wave energy converter (ARR WEC) integrating multiple-point absorption and raft type wave energy capturing technologies is proposed and experimentally investigated in this study. A 10 kW pilot device was developed, and a three-month real sea test was carried out in the Taiwan Strait, China. The experimental results confirmed the feasibility and effectiveness of the new system. The overall performance, heaving performance, power output and wave energy conversion efficiency of the pilot APR WEC running under random waves are reported and analyzed in detail. The heaving motions of the oscillating buoys and the instantaneous and average power output of the permanent magnet generator (PMG) are affected significantly by the number of oscillating buoys used to collect wave energy. More oscillating buoys used increase the production of electricity and improve the power quality, but lead to the reduction of energy conversion efficiency in long wave periods. The increase of electrical resistance of PMG results in an increased wave conversion efficiency. The experimental results obtained are valuable in the optimal design and operation of the ARR WEC system proposed.

The western Chongqing region is the main grain-producing area in Chongqing. This region's soils are characterized by light-to-moderate cadmium (Cd) pollution. Two types of typical paddy soils in this area (acidic and calcareous purple soils) were selected for the development of safe rice production techniques using in situ field remediation experiments. These involved a low-Cd-accumulating rice variety (Changliangyou 772) grown either alone or in combination with heavy metal passivators (silicon-calcium fertilizer, iron powder, biochar, and straw organic fertilizer). The results showed that:① all of the passivators except for the Fe powder increased rice yields from both types of soils. Straw organic fertilizer showed the best results for the acidic purple paddy soil, with a rice-yield increase of 47.43%, while biochar performed best for the calcareous paddy soil, increasing yields by 23.95%; ② The low-accumulation rice variety alone could not meet the requirements of safe rice production in the acid purple paddy soil (pH=4.75); however, combined the with passivators (with the exception of the silicon-calcium fertilizer), Cd content in rice grains was reduced by 14.81%-54.88% to within the national safe food standard for rice (0.2 mg·kg

The present study proposed a floating multi-body wave energy converter composed of a floating central platform, multiple oscillating bodies and multiple actuating arms. The relative motions between the oscillating bodies and the floating central platform capture multi-point wave energy simultaneously. The converter was simplified as a forced vibration system with three degrees of freedom, namely two heave motions and one rotational motion. The expressions of the amplitude-frequency response and the wave energy capture width were deduced from the motion equations of the converter. Based on the built mathematical model, the effects of the PTO damping coefficient, the PTO elastic coefficient, the connection length between the oscillating body and central platform, and the total number of oscillating bodies on the performance of the wave energy converter were investigated. Numerical results indicate that the dynamical properties and the energy conversion efficiency are related not only to the incident wave circle frequency but also to the converter's physical parameters and interior PTO coefficients. By adjusting the connection length, higher wave energy absorption efficiencies can be obtained. More oscillating bodies installed result in more stable floating central platform and higher wave energy conversion efficiency.

Image category recognition and feature matching is an important access to visual information on the level of objects and scenes. So far, most works concerning local feature matching are limited in gray images. Designed for gray images, SIFT has been found to be a robust local invariant feature descriptor. However, much information is ignored since the color is discarded in traditional SIFT, and some mismatching problems happen due to this approach. To achieve a more accurate feature extraction and keypoints matching, more advanced method is desperately needed. In this paper, we present a group of color descriptors, to increase the performance traditional SIFT does in some occasions like outdoor scenes. Besides, a RANSAC algorithm is also analyzed and applied to our research, to leave out those obvious mismatching. RANSAC works well for images with many self-similar structures, which decreases mismatches significantly. Then we improved the method so that it converges in fewer iterations.

The characteristics of the external heat exchanger (EHE) for a 4 MWth circulation fluidized bed combustor were studied in the present paper. The length, width and height of EHE were 1.5 m, 0.8 m and 9 m, respectively. The circulating ash flow passing the heating surface bed could be controlled by adjusting the fluidizing air flow and the heating transferred from the circulating ash to the cooling water. The ash flow rate passing through the heat transfer bed was from 0.4 to 2.2 kg/s. The ash average temperature was from 500 to 750 °C. And the heat transfer rate between the ash and the cooling water was between 150 and 300 W/(m2·°C). The relationships among the circulating ash temperature, the heat transfer, heat transfer rate, the heat transfer coefficient and the circulating ash flow passing through the heating exchange cell were also presented and could be used for further commercial EHE design.

There is a contradiction in selecting the running temperature for CFB boilers burning Fujian anthracite, in order to simultaneously satisfy the requirement of efficient combustion and high desulfurization efficiency. Based on numerical simulation and industrial experiments, the effect of the running temperature on the carbon content in fly ash and the desulfurization efficiency were analyzed for two types of CFB boilers with different capacities. It is found that, with the rise of running temperature, both decrease quasi-linearly. For the 75 t/h CFB boiler, when the running temperature is lower than 950 °C, the carbon content in fly ash is very high, causing a low burnout efficiency; maintaining the running temperature at 1000 °C is favorable for the fine char to be burned out, however, continuous raise becomes almost useless. For 440 t/h CFB boiler, a higher burnout rate of the fine char particles can be obtained when the running temperature is kept at about 950 °C, and further increase brings no evident benefit either. For the 75 t/h and 440 t/h CFB boilers burning Fujian anthracite, considering both the boiler efficiency and the combustion desulfurization efficiency, the optimal running temperature should be respectively about 980 °C and 950 °C.

To reveal the variation of the inner flow field on a single function shower, numerical simulation was conducted for single-phase flow using water as the working medium. The standard k-ε turbulence model is employed to simulate inner flow characteristics. To improve the uniformity of outlet flow, according to the simulation results of the old shower, the mold structural have been modified. The results show that, the outlet shape and different size will affect the internal flow field. According to the old shower analysis of the flow, speed of the outlet fluctuations are more obvious, while the improved shower flow rate of the outlet distribution is more uniform and old shower exists of vortex in the two shares of water region, but improved shower vortex is smaller and the distribution of flow is also better than the former.

In order to improve the overall efficiency of energy utilization in silicon smelting furnace, a technology solution to recover the furnace radiant heat and exhaust energy was described in this paper; and based on the operation data of a 3200 KV•A industrial silicon smelting furnace, a 400 kW steam turbine generator unit was designed, and the economic benefit from the technology solution was also analyzed. The results show that this technology solution brings a remarkable performances of energy saving and emission reduction: about 14% of the supplying energy could be recovered; the investment payback period is between two and three years, the economic benefit from the technology solution would reach 4.72 million yuan in ten years.

VAV air-conditioning system has the characters of nonlinear and non-stationary under the influence of many factors, so it is hard to tune the parameters of the fuzzy control system. According to the structure and operation principle of VAV air-conditioning system, the monitoring system has been developed. The conventional fuzzy control algorithm, temperature self-tuning parameters fuzzy control algorithm and variable universe adaptive fuzzy control algorithm were researched in the system. The relationship between the scale factors and several main performance indexes of the system's respond curve like overshoot, steady-state error and transient time has been analyzed. The experiments results indicate that the variable universe fuzzy control algorithm can improve the performance of the fuzzy controlle, the combination property index decreases over 17%. The algorithm is feasible to use it on line since it is simple and need few system resources.

In view of the limitations of traditional uncorrelated Linear Discriminant Analysis (uLDA) of failure with singular within-scatter matrix and computationally expensive in solving the optimal discriminant vectors for a large and high-dimension dataset, an equivalent uLDA to Linear Discriminant Analysis (IDA) and a algorithm of uLDA based on generalized singular value decomposition is proposed to simply the computation and get over the singularity problem. The classification experimental results of four image and text datasets demonstrate the superiority of our algorithmover other traditional algorithms.