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Q43Y-85D type crocodile hydraulic clipping machine was taken as research object to optimization design. A finite element model for clipping machine was built using shell unit as fundamental unit. ANSYS12.0 finite element method was used to analyze the deformation and stress distribution of the shear platform model of hydraulic clipping machine. The result showed that the maximum equivalent stress at the dangerous area was 368.162 MPa and the maximum elastic strain was 0.1814×10-2 mm. After the structural optimization design, it was found that the maximum equivalent stress decreased to 186.238 MPa which did not exceed the material’s yield limitation 215 MPa and the maximum elastic strain decreased to 0.919×10-3 mm which satisfied the requirement of stiffness.

With the development of transportation, subway is more and more important to every city, but the security of underground railway track faces with serious challenges. Tunnel excavation cross-section types have rectangle, roundness, arch, composite one and so on. In the tunnel excavation under Feng-tian Road in Chongqing, we chose three cross-section types for obtaining optimal scheme by finite element method (FEM). The efficiency and reliability of the optimized tunnel excavation cross-section were demonstrated by simulation results by FEM software Abaqus, and the tunnel excavation engineering under Feng-tian Road in Chongqing. Hope that this work can provide a reference to other tunnel excavation engineering.

Transparent conducting aluminum-doped zinc oxide (AZO) films with different film thickness had been prepared on soda-lime glass substrates by radio frequency magnetron sputtering using a high density ceramic target. The structural, morphology, electrical, and optical properties of the AZO thin films were investigated by X-ray diffraction, scanning electron microscope, Hall-effect measurement and optical transmission spectroscopy, which were strongly influenced by film thickness. With the film thickness increasing from 140 nm to 710 nm, the resistivity decreases from 9.78 × 103 to 3.23 × 103 Ω.cm and an average optical transmission decreases from 88% to 80% in the visible range and the optical bandgap decreases from 3.47 to 3.24 eV.

The thermal effect arisen from absorbing inclusions is the main factor which causes the damage of optical materials or component irradiated by the longer pulse duration laser. The unsteady heat conduction depends markedly on both the thermal properties of inclusions and the parameters of laser. Based on the differential equation of heat conduction, the temperature distribution caused by single absorbing inclusion is solved by use of finite difference method. The effect of the laser intensity and the pulse duration on temperature field is analyzed in detail. The result demonstrates that the smaller size inclusion and the smaller pulse duration cause relative safe thermal effect, consequently, the less probability to be damaged by thermal effect.

The curriculum construction is a very important work leading to the excellent course. Welded Structure (including 40 class hours) is one of main and compulsory course for the major of Material Molding and Control Engineering in our university. It is very important and necessary to construct the course in time. Based on the project of High Quality Curriculum Construction for Welded Structure undertaken by the authors, this paper makes a discussion on the original ideas, goals and contents, strategies and measures of the project. Meanwhile, the course construction and reform of Welded Structure are introduced from following aspects, such as curriculum setting, teaching contents and methods, teaching staffs, teaching quality management and supervision, online teaching resource construction. The purpose of the paper is to provide beneficial references and experiences to facilitate the further curriculum construction and reform in higher school.

A steady thermal conduction model was presented to study the temperature field and thermal stress distribution in film irradiated by continuous wave laser. The thermal effects may arise from either the absorbing inclusions or the intrinsic absorption of film. Based on the plane thermal conduction assumption, the characteristics of damage resulted from local melting or evaporation and thermal stress were discussed. The damage region resulted from local melting or evaporation smaller than that from thermal stress. The circumferential stress σθis the main cause accounting for the stress damage. The normal stress perpendicular to the interface between film and substrate is the direct cause of drum type damage. The characteristics of damage in unsteady thermal conduction caused by pulse laser can be analyzed qualitatively by means of this model.

Transparent conducting aluminum-doped zinc oxide (AZO) films have been prepared on soda-lime glass substrates by radio frequency magnetron sputtering using a high density ceramic target at different substrate temperatures. The structural, morphology, electrical, and optical properties of the AZO thin films were investigated by X-ray diffraction, scanning electron microscope, Hall measurement, and optical transmission spectroscopy, and which were strongly influenced by substrate temperatures. Films with better texture, higher transmission, lower resistivity and larger carrier concentration were obtained for the samples fabricated at higher substrate temperature. The AZO film with the lowest resistivity of 4.63×10−4 Ω.cm and an average optical transmission of 92% in the visible range was deposited on the substrate heated at 450 °C. The optical bandgap depends on the deposition condition, and was in the range of 3.35~3.59 eV.

Background Tai chi (TC) is proposed as a potential option for the management of osteoarthritis (OA), however, its beneficial effect on patients with knee OA has not been convincing. Objectives To evaluate the effect of a 24-week TC program on physical functions in older Chinese women with knee OA. Methods Thirty-five older Chinese women with knee OA were randomized into TC group (n = 18) and attention control (wellness education and stretching) group (n = 17). Subjects in the TC group practiced the 24-form simplified Yang-style TC 2 to 4 times a week for 24 weeks with frequency gradually increased. Physical function was assessed using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC), 6-minute walk distance and stair climb time. Results Compared with the control group, the participants in TC group had statistically significant improvements in changes of the WOMAC total score (6.18 +/- 2.13 vs. 1.71 +/- 2.73, P = 0.000), the WOMAC pain subscale (1.36 +/- 0.22 vs. 0.07 +/- 1.00, P = 0.001), the WOMAC stiffness subscale (0.66 +/- 0.25 vs. 0.05 +/- 0.38, P = 0.043), the WOMAC function subscale (6.17 +/- 1.96 vs. 1.72 +/- 2.63, P = 0.000), the 6-minute walk distance (32.43 +/- 14.20 vs. 6.67 +/- 16.76, P = 0.003), and the stair climb time (2.27 +/- 0.74 vs. 0.27 +/- 1.24, P = 0.001). Conclusions This study suggests that TC provides a safe, feasible and useful exercise option for older Chinese female patients with knee OA.