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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.

This paper briefly introduces the design, construction and wave attenuation effect test of a kind of floating breakwater sheltering deep water aquaculture. This novel floating breakwater structure is composed of 28 standard modules and corresponding anchoring systems, and each standard module comprises a catamaran raft and a wave-attenuating and oscillation-inhibiting device, with a length of 30 m, a width of 7 m, a depth of 2 m and a draft of 1.1 m. Each catamaran raft employs a box-shaped multi-ribbed beam-and-slab structure, and was constructed using high-performance concrete and ferrocement materials and internally filled with polystyrene foam plastics. Each wave-attenuating and oscillation-inhibiting device uses a detachable split box-shaped structure and was pre-fabricated using high-performance concrete, with a length of 2 m, a width of 1.638 m and a height of 2 m. Each standard module is anchored using 6 anchor chains, each of which has an on-floor length of about 25 m. After construction, this floating breakwater system was tested for wave attenuation effect, and the data analysis results show that the floating breakwater system has a wave attenuation effect of up to 50 %.

The location and the overall arrangement of the charging stations is an important problem with the development of electric vehicles. It is related to the charging needs, city planning, service level of charging station, geographic location and competitive ability and so on. A distribution model of EV charging station is introduced in the paper. In order to describe the model preferably, this paper introduces the attractive factor of charging stations and the area-different factor. The model can give the charging station rational positions by analyzing the data of the traffic flow and the electric-consuming-rate of cars on the road. A case study is given to illustrate the applying the model.

This paper presents a analytical method to calculate the minimum clamping force to prevent slippage between the workpiece and spherical-tipped fixture elements during milling process. After the contact deformation between the workpiece and spherical-tipped fixture element is determined, the relationships between the workpiece displacement and the contact deformations are obtained. Based on the static equilibrium equations, these equations are combined and linear equations are obtained to calculate the tangential contact forces between the workpiece and spherical-tipped fixture element. According to the maximum tangential contact force, the minimum clamping force to prevent slippage between the workpiece and spherical-tipped fixture elements is calculated. At last, this method is illustrated with a simulation example.

Focus on equipment maintenance support informationization basic requirements, this paper introduced certain ordnance equipment maintenance support system based on B/S structure , carried on preliminary discussion on design of equipment integrated support system, gave a preliminary analysis and research on design ideas, system structure and function, auxiliary module.

The servicing industry is more prosperous than others recently, how to alternate a chain store corporation to invest or operate is an important subject today. For the risk reducible and adding more opportunities to profit, the investors should collect some information (such as competition, potential...) of the industry by some rules before to join them .Therefore, it is expected to use the method of the Grey Analytic Hierarchical Process to estimate the competition about the chain store corporation for supporting investors more opportunities to profit in this paper.

On the basis of human factors analysis of driver error accidents, this paper establishes the accident-causing index system due to driver errors and puts forward the use of trapezoidal fuzzy hierarchy - the grey correlation analysis method to analyze the accident-causing index model due to driver errors. Then this paper uses related data and proposed analysis method to obtain the weights order of accident-causing factors. The results reveal the main cause of accidents due to driver errors, and provide the reference for further research to prevent the traffic accidents.

Microsoft office Excel is an important part of the Microsoft Office suite of software that can be processed, statistical analysis of various data, with its quick style and rich functionality has been generally welcomed, but with the database networking and sharing trends deepening, Excel application bottlenecks in stand-alone mode began to appear, and the network is the computer information technology in today's inevitable end, I imagine combining ADO technology developed by Delphi Excel data server in order to break this limitation, changes in non-network applications Excel mode.Excel Data Server is a set of services and client program, the server deployed on the server, the client is retrieved by the query language SQL, Excel data file can perform various operations and customer interface directly to form a Web-based application systems, customer service not only to support the application at both ends of the LAN, you can also support the application on the Internet. In this paper, Delphi7.0 support, using ADO and RemObjects SDK tools to develop an Excel data server. RemObjects referred to RO. RO version a lot, but it is recommended to use RemObjects Data Abstract 6.0.43.801, Delphi's experience in the development of it appear to be more stable, server-side and client-side data connections and programming efficiency, data manipulation more convenient.

The paper presents an experimental study on the relationship betweenprocess parametersand surface integrity of powder-metallurgy high-speed steel S390 in ultraprecision grinding. The optimal machining parametershave been obtained based on the Taguchi quality design method.The affected layerinduced by ultraprecision grinding has a uniform white layerand an inconspicuous dark layer; there are some carbides in the white layer of some samples; a compressive residual stress field exists on the ground surface. In addition, experiments confirm that lapping can remove the white layer effectively and increase the compressive residual stresses with a growth rate of 65%.The derived results satisfy the real requirements in practice.

Coal gangue is a byproduct of mining process, filling the gangue in the road embankment can reduce the pollution caused by the gangue accumulation. Because the formation and type of rock is different, the performance of gangue is different. In this paper, the main types of gangue of Handan & Xingtai coal mining area was taken laboratory test, the mechanical properties and chemical properties of different gangues were compared to determine the feasibility of gangue filling in the road embankment, and the performance law of coal gangue.

The mechanical properties of foam asphalt mixture are investigated, including indirect tensile strength (ITS), moisture resistance, rutting resistance and fatigue resistance. The test results indicate the 40°C3d curing mehod can stimulate the 30d or 60d natural environment temperature (25°C) curing procedures, which can quickly evaluate the long term ITS of foam asphalt mixture with cement or without cement. Cement can obviously improve the ITS, moisture resistance and fatigue test. The paper recommends proper cement content of foam asphalt mixture should be in between 1.5% to 2.5%.