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A Fourier series method based on Mindlin theory and Hamilton variation principle has been proposed for the vibration modeling and analysis of composite laminated plates with arbitrary boundary conditions, in which the vibration displacements are sought as the linear combination of a double Fourier cosine series and auxiliary series functions. Three types of constrained springs are introduced to establish a general structural model of composite laminates, and the vibration model is established by combining the Hamilton energy principle. The accuracy, efciency and validity of the two solutions presented are demonstrated via comparison with published results. The influence of boundary conditions, laying angle and laying layer on vibration characteristics is analyzed. And it can be seen that the frequency of the structure increases with the increasing of the spring stiffness and the number of laying layers of the boundary of the laminated plate structure.

In this paper, a theoretical model to evaluate impact sound transmission through a homogeneous wall is proposed. The model which is based on the Statistical Energy Analysis framework exhibits a system with room-wall-room. For the purpose to explore the mechanism of impact sound transmission through a wall, the impact sound reduction index between two rooms are predicted. Meanwhile, the variation of impact sound reduction index with the walls properties are also taken into account. The results reveal that the density, elastic modulus and thickness of a homogeneous wall have diverse effects on its impact sound insulation and can be chosen adequately to achieve ideal insulation values.It provides an approach to optimize impact sound insulating properties of the walls.

Coupling Loss Factor (CLF) is a parameter describing building sound loss, which can be stand for energy loss in the process of crossing the structure. A low value of CLF refers to the high insulation performance of building member. Therefore, reducing the coupling loss is a favorable way to improve the sound insulation. For the purpose of exploring the relationship between the properties of building materials and CLF, the commonly used building materials are selected to analyze. It is indicated that the properties of building material have obvious effects on the CLF. As the consequence, some predictions and analysis are carried out in this paper.

The operating characteristic of hydro-mechanical gearbox is vital to the vehicle performances. Basing on the testing terms of bench test and studying the dynamic operating performances of hydro-mechanical gearbox, a dynamic gearbox simulation model is built with the use of AMESim interface, which includes the engine model, torque converter model and the electro-hydraulic control model. The gearbox efficiency, the power loss without load, the oil pressure curve of clutch shift, all the parameters above could be simulated with the model. The results of gearbox experiments made sure that the gearbox is qualified the designing requirements and working in a good performance, which could be compared with the results of simulation to testify the correctness of the model, meanwhile, proved the perspectiveness and instructiveness of simulation model in gearbox designing and researching.

Water resources specific cloud computing platform (WRSCCP) is a solution to unify and formalize the developing process of water resources software, which will be helpful for improving developing efficiency and bring significant change to the uncontrolled developing pattern. However, compared with traditional platform, the cloud computing platform has its own security risk, for which the traditional security solutions are not adaptable. In this paper we analyze the security risk of WRSCCP and propose a security system to adapt to the characteristics of the water resources industry.

Statistical energy analysis (SEA) method is an adequate tool to solve complex problems to building acoustics. This research on the application in variety of the building materials as the subsystem of SEA model is performed. For the purpose to explore the relationship between the building element and its mode, these commonly used building materials are selected to determine this relationship. It is indicated that the properties of building material have obvious effect on the modal density and modal overlap of building members. As the consequence, a useful technique to account for a building member to be appropriate for a SEA (statistical energy analysis) subsystem is presented.

s: In this study, to understand the efficiency of lignin deconstruction by fungus-growing termite Macrotermes barneyi which feed on softwood only contained guaiacyl lignin, the wood metabolites in the hindgut of M.barneyi were analyzed using direct pyrolysis-gas chromatography-mass spectrometry. Significant cleavage level of propyl side-chain of phenylpropane in the hindgut was detected, and ring hydroxylation was also observed by the detection of syringal lignin. Compared with the reduction of furfural content, a pyrolysis product of pentose polymers in hemicellulose, reduction of the content of guaiacyl lignin which contained one-carbon side chain was huger in the hindgut, indicating the degradation of depolymered lignin is greater than that of hemicellulose. The analysis of lignin structure in the gut is contributed to understand the mechanism of lignin degradation by fungus-growing termite.

The ball's stress distribution in tractor servo disc brake usually is three dimensional in tractor. In this article,the contact theoretical analysis is used to calculate the contact face action distribution between the saddle ball bearings, the elastic displacement, train and stress distributed situation was determined in contact surface. The results show that the method is completely feasible, this method was suitable similarly for the solution contact stress question, the data has provided the important reference for the contact face optimization design.

Wave spring is a key component of multi-disc wet clutch and the response speed and running quality of multi-disc wet clutch is affected by its characteristics. This paper analyses the theoretical calculation of load-deformation relationship of wave spring. The load-deformation relationship of wave spring is obtained by ANSYS10.0 software according to its structural characteristics and actual boundary condition and compared with the calculated results based on different methods and the measured value, and then study the effect of the wave number on the load-deformation relationship of wave spring. The results show that the calculated value of finite element analysis (FEM) is closer to the measured value and the FEM has more advantages on simulation of the working performance of wave spring.

This paper models the controlled object with varying sample period by using predicted delay as sample period based on model and proves a necessary condition for making the system stable using Lyapunov function, then obtain the real-time controller gain in every step with LMI. The three cases illustrate the correctness and validity of the proposed method.

s: The paper extracted the flavor components of Hongdao Clam by using HS-SPME Technique and made an analysis of it by GC-MS. It compared the analysis results of 75 μm Carboxen/PDMS microextraction fibers and 100 μm PDMS microextraction fibers, with the result that the later one was suitable for flavour substance analysis of Hongdao Clam. Besides, by comparing the flavor components of Hongdao clam meat and soup, the thesis reached a conclusion that there are eight common ingredients in them, as well as the type and relative percentage composition of the flavor substance. This research provided a reference for the application of combining SPME and GC-MS techniques in aquatic product processing industry.

According to compressor working conditions and compressor lubrication performance requirements in this paper. It use a polyether and dioctyl sebacate as the base oil, and adding a variety of functions of composite additive deployment, Develop a kind of a compressor oil used on compressing and filling sulphur dioxide (SO2) in the supercritical condition. Experiments show that the developed compressor oil not only meets the performance requirements of compress and filling SO2 in supercritical condition, but also has a very strong adaptability condition.

The nano-indentation response and the friction and wear properties of the CNx/SiC (carbon nitride /silicon carbon) double layer thin films (SiC films as interlayer) deposited on nanocrystalline titanium substrate using magnetron sputtering technique at room temperature were investigated. The results show that the CNx films exhibited a low nano-hardness of 8.0 GPa and Young's modulus of 55.0 GPa but a high hardness-to-modulus ratio of 0.146. As sliding against Si3N4 (silicon nitride) ball under Kokubo simulation body fluid (SBF) at room temperature, the CNx films exhibited the superior tribological properties with the friction coefficients of about 0.1 and the special wear rate of about 1.6×10−6 mm3/Nm.

TiB2-TiN composite films/SiC films (SiC films as interlayer) were deposited on biomedical titanium alloy (Ti6Al4V) through magnetron sputtering technique. The friction/wear behaviors of the TiB2-TiN composite films under Kokubo simulation body fluid (SBF) were investigated. The results show that as sliding against Si3N4 ball (4 mm in diameter) at 200g load, the TiB2-TiN composite films exhibited the superior friction/wear properties with the friction coefficient of 0.22, the special wear rate in the magnitude order of 10−6 mm3 m−1 N−1together without interface delaminating. It was found that the films exhibited navel adhesion to Ca and P elements in Kokubo SBF. The present results demonstrate the possibility of developing the surface modification procedure of combining superior wear resistance and good osseointegration for application of orthopaedic implants.

A wear-resistant SiC (silicon carbon) film on titanium substrate was prepared by magnetron sputtering technology. The film exhibits low nano-hardness of 12.1 GPa and low Young's modulus of 166.2 GPa together with superior friction/wear properties. As sliding against Si3N4 (silicon nitride) ball (2 mm in radius) at room temperature under Kokubo simulation body fluid condition, the film exhibited the friction coefficient of about 0.215 and the special wear rate in the order of magnitude of 10−5 mm3/ Nm even at the load of 500g without film cracking and interface delaminating. The high film-cracking and interface-delaminating resistance is due to the low hardness of the film and the good film/substrate modulus match caused by the low elastic modulus of the film.

In this paper, both the TiB2/SiC bilayer films and the carbon-doped TiB2(TiB2-C)/SiC bilayer films (SiC films as interlayer) were successfully deposited on quenched Cr12MoV steel substrate through magnetron sputtering technology, and the carbon-doping effect on microstructure and friction/wear properties of TiB2films were investigated. The results show that the doped-carbon presented in manner of sp3C-C and sp2C-C bonds i.e. DLC (diamond-like carbon). As sliding against steel balls under dry frictional condition, the doped-carbon strongly decreased the friction coefficient of the films and the material transfer from the friction pairs to the films. At the same time, the doped-carbon reduced the wear rate of the films, the wear rate of the TiB2films and the TiB2-C films were both in the magnitude order of 10−5 mm3m−1N−1, this is due to more material transfer significantly adhered on TiB2films than on TiB2-C films.

The nano-indentation and friction/wear properties of a magnetron sputtered SiC (silicon carbon) films on nanostructured titanium (produced by severe plastic deformation) substrate were investigated. The results show that the films exhibited low nano-hardness (10.6 GPa), low Young's modulus (83.3 GPa) and high hardness-to-modulus ratio (0.128). As sliding against Si3N4 (silicon nitride) balls (2 mm in radius) under Kokubo simulation body fluid (SBF) at room temperature, the films displayed superior friction/wear properties at the considerably high normal load of 1000g, with the friction coefficient of about 0.18, the special wear rate on the order of 10−6 mm3 N-1m-1 without film cracking and interface delaminating. The impressive film cracking and interface delaminating resistance is in accordance with the low hardness (high ductility) of the films and the small film-substrate modulus difference that was caused by the low modulus of the films.

The microstructure and friction/wear properties of TiB2-C (carbon-doped TiB2) films in TiB2-C/SiC double layer films (SiC films as interlayer) deposited on Ti6Al4V alloy substrate using magnetron sputtering technique at room temperature were investigated. The results show that the TiB2-C films exhibited the microstructural characteristics with nano-scale particles (domains), and the doped-carbon presented in manner of sp3 C-C and sp2 C-C bonds i.e. DLC (diamond-like carbon). The interface between the substrate and the SiC films and the interface between the SiC films and the TiB2-C composite films both showed good adhesion, with obvious element diffusions. As sliding against Si3N4 (silicon nitride) balls (2 mm in radius) using ball-on-disc type wear tester at room temperature under Kokubo simulation body fluid (SBF) and 50g load, the TiB2 -C composite films exhibited the friction coefficient of about 0.14 and the specific wear rate of 10.710-6 mm3 m−1 N−1. It is believed that the superior friction properties of the TiB2-C films are due to the role of the doped-carbon.

Although a lot of interface crack problems were previously treated, few solutions are available under arbitrary material combination. This paper deals with one central interface crack and numerical interface cracks in a bonded strip. Then, the effects of material combination on the stress intensity factors are discussed. A useful method to calculate the stress intensity factor of interface crack is presented with focusing on the stress at the crack tip calculated by the finite element method. For one central interface crack, it is found that the results of bonded strip under remote uni-axial tension are always depending on the Dunders’ parameters , and different from the well-known solution of the central interface crack under internal pressure that is only depending on . Besides, it is shown that the stress intensity factor of bonded strip can be estimated from the stress of crack tip in the bonded plate when there is no crack. It is also found that when , when , and when . For numerical interface cracks , values of and with arbitrary material combination expressed by , are obtained.

Adhesive joints are widely used as the joints with the same or different adherents, such as in engineering and electric devices. However, because of mismatch of different materials properties, failures due to crack initiation and propagation are often observed on the interface between adhesive and adherents. Therefore, it is important to analyze stress intensity factor of crack on the interface. In this paper, the effect of material combination of adhesive and adherents on stress intensity factor and effect of the thickness of adhesive on stress intensity factor are discussed. A useful method to calculate the stress intensity factor of interface crack is presented with focusing on the stresses at the crack tip calculated by finite element method. The stress intensity factors are indicated in charts under different thickness of adhesive . It is found that the intensity of singular stress first increases with increasing , then decreases from about , and keeps constant from about , when is the width of adhesive. These results are helpful to design dimensions of devices and choose appropriate materials when adhesives are used inside of them.

The surface morphology of materials is of fundamental importance to many applications (e.g., surface wetting, friction, surface roughness, reflection, drag, adhesion, etc). Various approaches for micro/nano patterning atop polymer surfaces have been proposed in recent years. However, a cost effective technique is still highly in demand. In this paper, we demonstrate a few novel but rather simple and generic approaches for surface micro/nano patterning using shape memory polymers (SMPs). Reversible micro vertical chains, crown shaped protrusion arrays and strip/labyrinth wrinkles atop SMPs are presented.

A new system of thermoset styrene-based shape-memory polymer (SMP) filled with carbon black (CB) is investigated. To realize the electroactive stimuli of SMP, the electrical conductivity of SMP filled with various amounts of CB is characterized. The percolation threshold of electrically conductive SMP filled with CB is about 3% (volume fraction of CB), which is much lower than many other electrically conductive polymers. When applying a voltage of 30V, the shape recovery process of SMP/CB(10 vol%) can be realized in about 100s. In addition, the thermomechanical properties are also characterized by differential scanning calorimetery (DSC).

This paper is concerned about a design of a new deployable antenna actuated by 6 shape memory alloy (SMA) hinges. The antenna consists of 6 radial, tensioned, parabolic, deployable ribs connecting to a central hub. The hinge, located at each rib, is used of the Nitinol SMA material due to the ability to generate large strains and electrical resistive actuation. The elongated SMA wire is heated by an electrical current, caused to contract in response to a converse thermally-induced phase transformation. The resulting tension creates a moment, imparting rotary motion between two adjacent beams. The concept and operation of deployable antenna system are discussed in detail, and a dynamic simulation is presented. A series of experiments are performed on the SMA actuator to investigate the system behavior in the process of deployment. Results indicated that the hinge with low speed rotation and easy fabrication achieves reliable actuation for the deployment of the antenna, and the antenna demonstrates a high deployment-to-stowage volume ratio.