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Aiming at the safety accident caused by the close distance between the crane arm and the high-voltage line when the crane is working near the high-voltage transmission line, this paper proposes a simulation model of the electric field intensity distribution of the high-voltage transmission line. First, through the simplification and equivalent treatment of the high-voltage line, the simulation modeling, and analysis of the electric field around the high-voltage line are carried out. Then, the theory of solving the electric field intensity of any point around the high-voltage line based on the charge simulation method is deduced, and the conclusion that the electric field intensity at the equal distance of the high-voltage line is approximately equal is obtained. Furthermore, the influence of the crane on the electric field strength of a high-voltage line is analyzed, and the linear correction function of electric field strength is obtained. Based on the research in this paper, the field strength sensor can be used to obtain the value of the electric field strength, calculate the distance between the crane and the high-voltage line, and make a safety warning response. The simulation results verify the feasibility and effectiveness of the proposed model and method.

Aiming at solving the problems of complex image background and difficulties in the later image segmentation, an image segmentation algorithm based on the chaotic particle swarm algorithm and fuzzy clustering is proposed. First, the color space is converted from the RGB color space into the HIS color space. Then, a hybrid algorithm consisted of chaotic particle swarm optimization and fuzzy clustering is introduced. Each color component is processed by the algorithm, and the corresponding partition graph is obtained. Finally, the color space is converted into the RGB color space to achieve the segmentation effect. Experimental results show that the new algorithm has higher accuracy to segment the image and has good robustness to noises.

In this study, isotropic wet etching technology has been developed to achieve the pyramidal needle structures on one side polished chemical pure titanium substrate. Different etchants, mask materials and substrate materials combinations were investigated respectively for process optimization. A steady etch rate in excess of 2µm/min has been achieved with sputtered Ni mask. For the first time, bulk titanium out-of-plane microneedle array was fabricated with excellent sharpness. By aqueous oxidation, nanostructured porous titania was generated on the surface of the microneedle, which not only enhanced the biocompatibility of titanium devices and implants but also provided an approach for drug loading. With its high fracture toughness, high strength, and excellent biocompatibility, the bulk titanium out-of-plane microneedles may play an important role in the future clinical applications.

Nanostructured titania (NST) is attracting more and more attention due to its porousness and high surface to volume ratio. A novel process to fabricate integrated NST thin film at low temperature (80-90°C) is presented. NST features were formed by oxidizing Ti films in aqueous hydrogen peroxide. The optimal conditions of aqueous oxidation are: 85°C, aqueous 10% H2O2 solution, 20 min of water bath time. Crack-free NST features of 100 ?m × 100 ?m were successfully fabricated. Two polymer masking materials, SU8 and Parylene, were proved to be compatible with this process, selective NST oxidation could be carried out at an ultra low temperature below 100°C.

In this paper, we present a new technique that could realize wafer level 3-D hermetic package in a very low bonding temperature (120°C) for MEMS (Micro-electro-mechanical Systems) devices. Microcavities were etched on a host glass wafer and were bonded with a carrier silicon wafer. MicroChem SU-8 photoresist is used as the intermediate adhesive layer between the host and carrier wafer. The devices were fabricated by self-aligning etching technique and were finally sealed by coating the structures with sputtered aluminum. Helium leak testing is carried out to verify the hermetic characteristics of the package, 99.7% of the tested devices were qualified. This technology shows a significant improvement of the hermeticity properties of adhesive bonded cavities, making it particularly suitable for applications on gas-tightness with low temperature, non-aggressive demands.Copyright © 2007 by ASME

In this study, the hydrogen response of Pt-coated WO3H2O nanoplates before and after annealing is investigated and the interaction mechanism is revealed using in situ Raman spectroscopy and quasi in situ x-ray photoelectron emission spectroscopy. We find that structural water molecules form in the nanoplate during its interaction with hydrogen. However, the generation of oxygen vacancy is not observed. Generation of in-plane compressive stress is evidenced, which suggests that the valence states change of W atoms during the interaction is related to the structural displacement due to the formation of structural water. The enhancement of gas response performance after annealing is due to the transition from orthorhombic to monoclinic phase, which causes the reduction of formation energy of lattice O–H bonding and increase of reactive sites in WO6 octahedron.