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A point interpolation mesh free method using radial basis with polynomial reproduction is presented for static and mode-frequency analysis of two-dimensional piezoelectric structures. In the present method, the problem domain and its boundaries are represented by a set of properly scattered nodes. The displacements and the electric potential of a point are interpolated by the values of nodes in its local support domain using shape functions derived by the PIM scheme. Variational principle is used to establish a set of system equations for arbitrary-shaped piezoelectric structures. These equations are assembled for all quadrature points and solved for displacements, electric potentials or natural frequencies. A program is coded in MATLAB based on the formulations. Numerical examples are also presented to demonstrate the validity and convergence of the present method and their results compare well with the conventional FEM results from ABAQUS as well as the experimental ones.

A novel serial-parallel hybrid quadruped robot is presented to solve the problem that the robot based on the directly serial leg mechanism has great weight/load ratio and weak static performance, and the static analysis on the serial-parallel leg of the robot has been carried out. Considering the mapping of constraint and actuation forces, the statics equilibrium equation was established based on the vector theory and virtual work principle. Global stiffness index was defined, which can measure quantitatively the deformation within the workspace of the leg. Giving out the parameters of the hybrid leg, according to the static model, force and torque curves of hybrid leg’s four drive motors were drawn by MATLAB when its foot moved along a given trajectory with 100 N force exerted upon it along three different axes. Result of the simulation shows that the hybrid leg has best carrying capacity of force in the x-axis direction, while in z-axis direction is the worst. This research is of great significance to a series of further studies upon dynamic properties analysis, mechanisms optimal design and system control of the novel serial-parallel quadruped walking robots.

Under the background of the truss bridge in Gaoliang ship lock across Huaihe river, which is made of glass fiber reinforced polymer (GFRP) profiles, APDL language based on ANSYS is used to organize corresponding command stream program and built 3D finite element model. According to the actual situation of the bridge, the static analysis and modal analysis of the truss bridge to test the static and dynamic performance is conducted. The mechanical property when the bridge material was replaced with BFRP and CFRP is analyzed.

The development of the global marine industry led to a surge in demand for offshore platform crane, due to its complex working environment makes the research for offshore platform crane is less, So the strength calculation and modal analysis of the boom of the offshore platform crane are carried out by using ANSYS in this paper. Firstly, the load of the offshore platform crane is analyzed based on the API-2C specification; then the static analysis and modal analysis of the boom are carried out by using ANSYS and obtain the weak points, natural frequency and mode shapes of the components. The analytical results show that the material of boom meet the requirements of strength and stiffness; because the natural frequency of the winch drum and the fluctuating wind load and the boom is partially overlapped, we should pay attention to the speed of the winch drum or the structure reforming of the boom in order to avoid resonance in using.

The static strength analysis of a diaphragm coupling with joint bearing is carried out by using ANSYS, we find that the diaphragm coupling can bear the force with only 1.5 times the maximum torque, 13228 rpm rotational speed or 12 mm compensation respectively, it can be used safely; when the diaphragm coupling is forced with combined loads(with 2000 N axial force), the coating of diaphragm coupling forced more than compression limit, there are security risks; when the diaphragm coupling is forced with combined loads(with less than 1850 N axial force), it can be used safely.

AndroPyTool is a tool for the extraction of both, static and dynamic features from Android applications. It aims to provide Android malware analysts with an integrated environment to extract multi-source features able of modelling the behaviour of a sample and that can be used to discern its nature, whether malware or goodware. AndroPyTool integrates well known tools in this field, such as AndroGuard, DroidBox, FlowDroid, AVClass, VirusTotal or Strace, which allow to obtain a wide set of features including Application Programming Interface (API) calls, permissions, labels obtained from the different antivirus engines included in VirusTotal, Source-Sinks data connections, API calls invoked in real time, accessed files, files operations and many others. AndroPyTool is an open source tool that can be used via both the source code and a Docker container, in just three stages (pre-static, static and dynamic analysis).