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A fuzzy nonsingular terminal sliding mode control scheme for the attitude of flapping wing micro aerial vehicle is proposed in this paper. Based on the feedback linearization technique, a nonsingular terminal sliding mode controller is designed. To reduce the chattering in the control input, a fuzzy controller is designed to adaptively tune the switch part gain of nonsingular terminal sliding mode controller according to the nonsingular terminal sliding mode surface. The stability of the control scheme is verified by using Lyapunov principle. Simulation results show that the proposed control scheme is effective.

Waste mobile phone has become the largest number of electronic waste, and recycling of metals from mobile phone would ensure resource recycling and reduce environmental degradation. Based on the contents of metals analyzed by Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES), containing copper and precious metals such as gold, the paper compared the extraction processes of gold, copper from waste mobile phone printed circuit board (PCB). In this study, two processes, nitric acid and thiourea (NT), sulfuric acid-hydrogen peroxide and iodine (SAHPI) were used to leach copper and gold, respectively. The recovery rate of copper was found to be 96.42%, and 94.3% of the gold was leached in the former process. Similar trends were obtained for the leaching of copper and gold in the latter process, but it was lower that about 95.27% of copper was recycled, while 93.4% of gold were leached. Both the two processes were nontoxic and non-cyanide system. However, thiourea is not stable and easy to decompose in alkaline solution, and the technology has disadvantage of instability. Iodine leaching on the other hand is comparatively a environmental process. Therefore, the optimal choice is the combined process of SAHPI method, while further research is required to develop cost effective and environmentally friendly processes.

Large long corridor surge chambers have unique form. As a typical hydropower underground structure, its stability of surrounding rock in the process of excavation and force features of structure are affected by particular structure form. Take a hydropower station for example, by using the finite difference method, we simulated two different schemes in process of excavation and analyzed its displacement, stress, plastic zone of surrounding rock as well as force feature of structure. Appropriate law of large long corridor surge chamber during excavation is summarized which will provide the reference for the similar project.

The rapid growth in end-of-life electronic products in recent years has seriously threatened the environment. While if the renewable resource industry introduced the concept of modern logistics, they will be the best carrier for the activities of reverse logistics. The paper aimed to find out the way for the renewable resource enterprises taking part in the reverse logistics, and how they could cooperate with the Manufacturing Industrial Park, and then form the Regional Eco-Industrial Park. This research took two typical districts of Tianjin Ziya Environmental Protection Industrial Park and Tianjin Economic Technological Development Area for example to discuss the foundation and the management for the renewable resource industry in Tianjin, and built a closed-loop supply chain for end-of-life electronic products recycling.

The three-dimensional (3-D) images of space targets with spaceborne along/cross track millimeter-wave (MMW) interferometric inverse synthetic aperture radar (In-ISAR) is studied under the condition of low SNR input in this paper. Because the traditional Range-Doppler (RD) algorithm can't get good performance when the target size is large and required high resolution. The wave number domain imaging algorithm is introduced to obtain two-dimensional (2-D) high resolution images of space moving targets. Then along/cross track interferometric processing is implemented for the three 2-D images obtained from three antennas to determine 3-D positions of the target scattering points. As the foundation of 2-D imaging and image registration, target detection and 3-D velocity estimation at low SNR input are studied here. The requirement for velocity estimation accuracy is analyzed. Finally, numerical experimental results are given to demonstrate the effectiveness of the along/cross track In-SAR system. [ABSTRACT FROM AUTHOR]

As the increase rate of municipal sewage treatment, the reuse, disposal, and management of sewage sludge generated by wastewater treatment have become an issue of public concern due to the substantial quantity of sludge generated in China. On the basis of summarizing technologies of sludge disposal at home and abroad, the paper sampled and analyzed pH, moisture content, nutrition contents and heavy metal contents in sludge from Tianjin Qingninghou landfill, to assess the possible utilization technologies. The testing results showed that the concentrations of Cu, approximately 1790.97mg•kg-1, was so high that sludge can not be reused from Dongli wastewater treatment plant, while dredged sediment from Dagu River could be used in co-landfilling, land improvement of neutral and alkaline soil, the production of cement clinker, as well as further dewatered and dried sludge from Jizhuangzi, Xianyang Road and Beichen wastewater treatment plant. In addition, sludge could be used for acid soil improvement and making brick from Jizhuangzi and Beichen, to extend life of the landfill and achieve the goal of sustainable development.