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Aluminum alloys exhibit poor weldability by conventional fusion welding process. The heat treatable aluminum alloy AA2014 is extensively used in the aircraft industry because it has good ductility and high strength to weight ratio. In this paper the effects of welding parameters and tool profile on the mechanical properties of friction stir welded butt joints of dissimilar aluminum alloy sheets AA6082 and AA2014. The process parameters such as rotational speed, transverse speed and axial forces were considered. The effect of parameters on weld quality was analyzed. Hardness and tensile tests are carried out at room temperature to examine the mechanical properties of the welded joints. The joints produced with straight square tool pin profile have higher ultimate tensile strength, whereas the straight cylindrical tool pin profile results in lower tensile strength.

Biped robot with heterogeneous legs (BRHL) is a new pattern humanoid robot. This paper first introduces the conception, research purpose and configuration of HRHL. Then coordinated dynamics model and magneto-rheological (MR) damper model are given. In the end, this paper discusses the control model of BRHL and gives combined control simulation. The result indicates that intelligent bionic leg controlled by MR damper can track artificial leg’s gait well.

The demand for town houses using the constructions of lightweight conrete is growing rapidly in recent time. One of the most common building materials for cottage construction is lightweight aggregate blocks. An important role for lightweight expanded clay aggregate (LECA) concrete plays such a property as vapor permeability. This paper presents the results of vapor permeability test of the samples, the analysis and recommendations for construction of the building. These samples were taken from the LECA concrete blocks covered by unidentified cladding, of which one of the town houses was under construction in the North-West of Russia. An assumption has been made that the unidentified cladding may cause losses to the building’s wall enclosure.

Graphene is a material that has been heavily investigated in many researches due to its beneficial characteristics such as large surface area, low manufacturing cost, high electro conductivity and incredible mechanical strength. Applying the graphene in water-based solvents however can cause agglomeration due to its hydrophobic properties. Researchers have composited the graphene with other materials in overcoming its hydrophobicity. In this research, graphene was nanocomposited with thionine to make it disperse well in water-based solvents while preserving its intrinsic properties. The nanocomposition process involves mixing of both graphene oxide with thionine and were reduced by hydrazine hydrate while reflux heating. The produced mixture was then filtered to obtain the Thionine-Graphene nanocomposite. The obtained sample was then characterized to confirm the composition of both graphene and thionine. Fourier transfer infrared spectroscopy was operated to investigate the chemical bonds and hence concluding the presence of both graphene and thionine in the sample. The preservation of the intrinsic properties of graphene was also investigated through observing the absence of functionalized graphene bonds. Post-investigation reports that the chemical bonds from both of the materials, graphene and thionine were detected confirming the successfulness of the nanocomposition.

This paper discusses and analyzes the development process of economic type mechanical engraving machine, including the system overall layout, structure scheme, the movement mode of numerical control system, mechanical system design process and the design process of the control system and the "mechanical engraving" the choice of interpolation algorithm, analysis and implementation process. Compared to the same function of the CNC engraving machine, has certain advantages in terms of price, to fill the gaps in the domestic and foreign enterprises, to meet the market demand.

In this paper, the multilayer frame structure containing sheet crack was researched. Based on wavelet analysis theory, the finite element method was applied to analyze the dynamic characteristics of structural damage. Established a method about the identification of containing sheet crack frame structure by modulus maxima of wavelet coefficients to determine the location of the crack, it verifies the validity of the method through calculation analysis of damage identification to a two layers of a cross frame structure containing sheet crack. The conclusions of this paper can be used for frame structure damage diagnosis application reference.

This paper designs a multi parameter real-time water quality on-line monitoring system for aquaculture water. This system achieves the online monitoring among temperature, turbidity, DO (dissolved oxygen), pH and electrical conductivity. The crosstalk, produced by the simultaneous measurement with DO and pH sensors, will affect accuracy and stability of monitoring results. This paper analyzes the source of crosstalk, describes a circuit model of causing crosstalk, and designs an isolated circuit between powers and signals as well. The experimental results show that, the real-time monitoring of DO and pH has the characteristics of speediness, high precision, small error and low noise.

Oculomotor plant and saccade generator are the basics of the saccadic system. The purpose of this paper is mainly focused on mathematical models of horizontal eye movement system. In this respect, it is presented a model for the mechanics of horizontal eye movement. The oculomotor system is presented incorporates known physiological dynamics and musculotendon complex geometry. Developing muscle strength can be described by a two-component version of the model Hill and consists of a passive and active contractile component. The active component includes force-velocity and force-length characteristics of the muscle. Passive component accounts for elastic and viscous effects. Couple neuronal activation dynamics controls that is appropriate for judder from muscle mechanics.

Adopted the load-structure model to tunnel structure design calculation, our country often use surrounding rock pressure experience calculation formula, This paper analysed the problems existing in the experience calculation formula and calculated the surrounding rock pressure have influence on calculation results of tunnel structure internal force with the formulas, and at last given out more actual modification formula, the surrounding rock stress is continuity with the formula calculated, it is more actual than the traditional experience formula, provided a new way for accurate calculated the surrounding rock pressure.

In classic radial sampling scheme, angle intervals between adjacent straight sampling lines are the same. And so the coherence between the sampling matrix and the sparse matrix is high. Many pseudo-shadows will occur on the reconstructed image. For this problem, we put forward a novel sampling scheme in which the scan lines are placed in the manner of golden section angle interval. In the resulting sampling matrix, the scan lines scatter randomly on the whole. Experimental results demonstrate that the algorithm proposed in this paper has lower correlation coefficient between sampling matrix and sparse matrix than classic radial sampling scheme and random radial sampling scheme. Image can be accurately reconstructed by collecting less data than the other two schemes.