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The output power of Direct Methanol Fuel Cells (DMFC) is one of the most important elements which limit the performance of DMFC. In order to enhance performance of DMFC, it is necessary to have model to modeling the output power of DMFC. In this paper, a novel model base on Support Vector Regression (SVR) to modeling the output power of DMFC base on output current (I) and operating temperature (T). The test result is shown that the generalization ability of SVR model is high accuracy. This investigation suggests that SVR is quite satisfied used to developing a DMFC model and can be used for controlling, optimal designing and feasibility study of the DMFC system.

The characteristics of quasi-zero stiffness(QZS) system with nonlinear positive and negative stiffness is researched. A modified QZS model with nonlinear spring element is established and the stiffness curves are obtained based on the analysis of relationship between spring force and displacement. A non-dimensional form of QZS is deduced to discover its essential laws, and simulation is presented with different nonlinear springs. Then the force transmissibility of QZS is verified with the experiment, which shows that the QZS isolation performance is better than the linear one in the low frequency band, and there exists no resonant peak in this system.

This study focus on derivation of such vulnerability curves using Fiber Reinforced Polymers technologies retrofitted conventional RC industrial frames with masonry infill wall. A set of stochastic earthquake waves which compatible with the response spectrum of China seismic code are created. Dynamic time history analysis is used to compute the random sample of structures. Stochastic damage scatter diagrams based different seismic intensity index are obtained. Seismic vulnerability of FRP-reinforced RC industrial frames is lower than unreinforced frames obviously, and seismic capability of frames using FRP technologies is enhanced especially under major earthquake.

To make diesel engine Exhaust meet Euro V standard , the most efficient way was to use SCR(Selective Catalytic Reduction).In this paper ,the composition of the urea-SCR system, essential parts and technology of urea-SCR and the strategy to reduce NOx exhaust was analyzed carefully. And through the test analysis, Selective catalytic reduction technical could Euro V diesel engine emission standard had confirmed.

Water resources reasonable disposition is a measure to solve water shortage problem, cannot still meet the requirement of practice for the knowledge of complex water resources system and the method of describing and other theoretical research. The Yellow River has faced the dry-up of the Yellow River. A Synthetic Decision Support System (SDSS) for water resources dispatch and allocation, based on a new route and method to water resources dispatch and allocation derision-making was developed in order to gain a better understanding of the water resources dispatch and allocation. The paper completes the design of the main structure and functions of the system, and introduces the key techniques of implementing the system, through the analysis of application subject and information integration manner of the system, topological relationship between the water conservancy project entities in various river basins is established using the thought of graphic-topology and tree-topology. Adopting the data warehouse technique, the integration method of facing the decision subject, separation method of the user interface and application program, the method of water resources dispatch and allocation service model based on topological relationship, is established. The model is integrated with the scenario experiences and knowledge about the water resources dispatch and allocation accumulated by the experts and developers. The system has been put into application successfully, and satisfied effects are obtained, therefore it is worthy to be improved and popularized and has the great directive significance and applied value in optimum operation regulation and uniform management of water resources.

In order to localize and identify the mechanical noise sources on the submarine, a kind of double-layer submarine model with ring-stiffened was established, and the broadband actuators were put on the inner structure to simulate the mechanical equipment. The radiated acoustic field of the submarine model was reconstructed by the near-field acoustic holography method, which was also compared with the theoretical acoustic field. The simulation results showed that the reconstruction pressure amplitude agreed well with the theoretical calculation results, indicating that the acoustic field of submarine model could be reconstructed accurately by the method of near-field acoustic holography, and the mechanical noise sources would be localized and identified accordingly.

To localize and identify the noise sources of the AUV, the cylindrical NAH method was proposed. The feasibility was verified by the acoustic field simulation, the influence of the array test distance, holographic planar array position errors and the reconstruction phase errors on the accuracy of the sound field reconstruction was analyzed, which would provide some references for the engineering applications.

Silica fume is a by-product in the production of ferrosilicon and industrial silicon material. With the ultrafine physical structure of and high volcanic ash activity, silica fume is more important admixture in concrete improving the strength and durability of concrete, and it is widely used in high performance concrete engineering. Influence of silica fume on mechanical property of high performance concrete is investigated in this paper. Experimental results show that the strength of concrete increases significantly when suitable dosages of admixtures is applied.

Electromagnetic transients simulation for the actual large-scale power systems usually needs long time. How to achieve the equivalent circuit of the external system and reduce the simulation system scale is one of hot topics in this field for a long time. In the paper, the main equivalent methods of external system are classified, the main content and process of each type method are described and its advantages and disadvantages are analyzed. On this basis, the development tendency and the key issues needing to be broken through for the external system equivalent method of power systems electromagnetic transients simulation are also presented in the paper.

In this paper, the vertex stability problem for a class of grey discrete dynamic systems was investigated by means of the matrix eigenvalues theory and spectral radius approach. Several necessary and sufficient conditions are obtained which can guarantee the vertex stability of grey discrete dynamic systems. The equivalence relation between the vertex stability and Schur stability of grey discrete dynamic systems , as well as the equivalence relation between the vertex stability for grey discrete dynamic systems and its boundary matrix are established.

The seismic response of space structures has been widely studied in the past few years. It has been shown that space structures behave well under seismic loading. However there has been little attention given to the effects of geometrical non-linearity on the seismic response. In this paper, a double-layer truss model was created by finite element analysis program-Lusas. The analysis process took into account of geometrical non-linearity and a 3D seismic loading obtained from a real earthquake. Time-history method was used to investigate the axial forces and displacements of critical members of the model during the earthquake. The seismic behavior of the model and the effect of non-linearity were finally discussed for further applications and studies.

A online automatic indexable inserts detecting system,which is based on the five-axis CNC grinding system,is introduced in this paper. The probe of the system can complete the online detecting of indexable inserts by calling the macro measurement program. The measruements of the inserts can be calculated and input into the process module.

A brief introduction on the forms,working principle and sorts of microbial sensors is given,the application of microbial sensors in the field of biological industry,environmental monitoring and clinical medicine are summarized.The prospects of bioensors are also prognosticated.

During long-time charge-discharge cycling, the capacity of the vanadium redox flow battery (VRFB) will reduce gradually. To recognize the capacity loss condition in the time of the operation process, a method for classification of the capacity loss degree based on Probabilistic Neural Network (PNN) is presented. The network inputs are the value of the voltage per second and the average power of the cell stack in any two minutes of the circulation. The network will give out three classes in form of three numbers to classify the capacity loss degree into different levels. The network is trained and validated by experimental data and the results show that the network is suitable for the classification problem of VRFB capacity loss and the method is useful to determine whether the capacity is sufficient and when to restore the cell capacity in real time.

A methodology to calculate the meshing tooth of giant magnetostrictive harmonic motor is proposed in this paper. The deformation curve of the flex spline of the giant magnetostrictive harmonic motor was investigated with Fourier function. A kinematic model of harmonic drive was established when the involute profile is selected as the flexible gear tooth shape and the circular spline is obtained following the envelope theory, thereby generating the kinematic simulation as well as the trajectory of the circular spline teeth with respect to the flex spline. Finally, the relationship between the cone angle of flex spline and the engagement profile is discussed; together with an improvement strategy-equal width shrinkage of circular spline.

With predominant influence on national welfare and people's livelihood, the construction of affordable housing is one of the most important livelihood projects of government. The developer agent-construction mode is put forward through the analysis of affordable housing's features and current main management modes. The new mode can perfectly adapt to the affordable housing construction with its unique connotation and specialty. And the practical application case of developer agent-construction mode shows its strong advantages, so it can be widely used in the construction and management of affordable housing.

Giant magnetostrictive actuator (GMA) has been used in precise position, active vibration control etc. for its merits of large output force and displacement. At low drive level, GMA presents linear relation between displacement and input current, while nonlinear appears when applied moderate or high drive level. This paper addresses the development of model-based adaptive sliding mode control designs for GMA operating in nonlinear and hysteretic regimes. Homogenized energy model in combination with a quadratic moment rotation model for magnetostriction is adopted in this paper to describe hysteresis of GMA, and its inverse model is employed as a inverse filter before GMA system to compensate the hysteresis and nonlinear. The proposed control law guaranteed global stability of the control system with certain accuracy in tracking desired trajectories. Simulation result verified the correctness and effectiveness of the extracted control method.

The indemnificatory housing project has many characteristics such as large scale, short-periodic cycle and diverse design requirement. With the aid of DMAIC theory we focus on analyzing and optimizing the design process of housing project, changing the logical relations between the procedures, eliminating unnecessary links and making some enhancement in defective ones, aiming to build up a design process, which the duration and cost are more less and the quality is higher, to meet its particularity.

This study focuses on obtaining such damage probability curves based on representative Inter-layer seismic isolation buildings (ILSIB) in China metropolis using whole spectral indicator. 30 corrected random earthquake waves are selected to represent the variability in ground motion. Dynamic time history analysis is used to analyze the random sample of structures. Random damage scatter diagrams based on different spectral indexes are all achieved. Index of damage probability based Sd indicator is most precise in all the spectral indexes because of the least coefficient of variation. Fragility in Y axis is more serious than in X axis through careful analysis.

In order to find a solution to the control of low frequency noise in the cabin of turboprop driven aircraft, an experimental active noise control (ANC) system is introduced in the paper, which consists of vibroacoustic field analogue subsystem, acoustic field measurement subsystem and acoustic barrier exciter subsystem. Effects of both different spaces between the primary sound source and secondary sound source of the ANC system and different frequency noises on noise-reduction result are investigated based on the experimental platform. Results of the experiment show a significant potential of the ANC method for the control of low frequency noise in the cabin of turboprop driven aircraft.

To study the kinematics characteristics of conventional suspension with double trailing arms for light off-road vehicles, suspension model of a light off-road vehicle was established on multi-body dynamics software ADAMS/View, which has double trailing arms and helical springs, and make the suspension kinematics simulation for getting the caster angle and front-wheel steering angle curves on different working conditions. The results show that the double trailing arm lengths, the angles between double trailing arms and horizontal plane/vertical plane, bushing stiffness of the double trailing arms linking with frame are main parameters that affect the caster angle and front-wheel steering angle. The suspension model is rational.

The economic growth in Shanghai is fast and its level of social development has reached that of the moderately developed countries, while shanghai has also been one of the highest CO2 cities. It has adopted many measures to control climate change. The rebound and reduce effect model has been used to analysis the effectiveness of the control of CO2 in the process of low-carbon policy implementation in Shanghai. This model will help policymakers reconsider the implication and limitation of low carbon policy. The results show that currently many policies used in Shanghai are of emergency, and rebound effect is obvious. However, these efficiency-oriented measures are suitable for Shanghai's own development needs.

The Yining char samples were prepared in following conditions that raw coal particle size was in range 5-6mm and pyrolysis final temperature was 900oC, 1000oC and 1100oC, respectively, with a heating rate 20oC/min under atmospheric pressure. The gasification reactivity of chars was performed by thermogravimetric analysis (TGA) at 900oC in steam, CO2 and steam/CO2 mixture, respectively. The results show that the gasification reactivity of chars decreases with the increasing of pyrolysis final temperatures and there is synergistic effect between steam and CO2 during co-gasification that influences the char reactivity. The reason may be explained by char structure change, which FTIR showed that –CH3 and –O–CH3 decreased and even disappeared and XRD analysis suggested that the thickness of microcrystalline Lc, the values of microcrystalline diameter La and the aromatic of char fa became larger with increasing pyrolysis temperature.

The characteristic of the acoustic radiation of vibrating structure is the important factor in valuing its performance. This paper puts forward a visualization system of the acoustic radiation based on NAH which combines the measurement, data management and visualization. The visualization technology it adopts point a new way to the observation of the acoustic radiation. Experiments have shown that this system can offer a complete solution for the measurement and research of the radiation field.

A method of mixed gas quantitative analysis with near infrared spectroscopy （NIR）is described. A single plane diffraction grating is used in the monochromatic spectrum system. A quantitative analysis system is designed and constructed according to the parameters of the monochromator. The narrowband beam testing and spectral scanning experiments with methane and ethane are carried out. A 10nm narrowband beam is successfully obtained by the monochromatic system when the entrance slit width is 2mm. And a step-scanning resolution of the outgoing beam’s centre wavelength with 0.1nm can be realized within the spectra of 1.0-1.8μm. The results show that methane and ethane have a maxim characteristic absorption spectrum respectively with the centre wavelength of 1653nm and 1690nm existing between the spectra of 1.6-1.8μm, which is consistent with the HITRAN database. Presented approach has a successful application in online mixed gas monitoring with the characteristics of simple structure and low cost.

A cluster kernel semi-supervised support vector machine (CKS3VM) based on spectral cluster algorithm is proposed and applied in winch fault classification in this paper. The spectral clustering method is used to re-represent original data samples in an eigenvector space so as to make the data samples in the same cluster gather together much better. Then, a cluster kernel function is constructed upon the eigenvector space. Finally, a cluster kernel S3VM is designed which can satisfy the cluster assumption of semi-supervised study. The experiments on winch fault classification show that the novel approach has high classification accuracy.

This paper focuses on the development of load-dependent hysteresis model for Giant magnetostrictive materials (GMM). GMM are a class of smart materials and which are used mostly as actuators for active vibration control. Magnetostrictive actuators can deliver high ouput forces and relatively high displacements. Here, Terfenol-D, a magnetostrictive material is studied. Unlike the hysteresis seen in magnetic materials, The shape of Terfenol-D hysteresis curve changes significantly if the load is changed. To meet performance requirements for active vibration control, an accurate hysteresis model is needed. By modeling the Gibbs energy for each dipole and the equilibrium states, load-dependent hysteresis of GMM is modeled. Then a new PSO-LSM algorithm is brought forward by combing the Particle Swarm Optimization (PSO) with the least square method (LSM).Throughout this algorithm the model parameters were identified. The model results and experimental data were compared at different loads. The simulation results show that the load-dependent hysteresis model optimized by PSO-LSM yields outstanding performance and perfect accuracy.

This paper analyzes the effects of the swinging NAH(Near field Acoustical Holography) measuring array on measurement of the sound power level of underwater structure. We use the method of sound intensity integral, the method of mean square sound pressure and the method of NAH reversal pressure to calculate the sound power level under certain collection of frequency with measuring surface in different states. We also analyze the relative error of results acquired by those methods, which can help validating the reliability and the error estimate of the results calculated with NAH.

The 3D surface measurement methods are described based on the single and multi-frame fringe projection principles, respectively. The key algorithm  phase reconstructing (PR) is conducted by means of two different concepts; one is the single-frequency spatial phase reconstructing method and the other is the multi-frequency temporal one. On the side of spatial PR, a few typical methods are carried out, among which the most robust one could be achieved. The described spatial methods are implemented under the guide of the suggested modulation gradient variance (MGV) map. Moreover, the network programming (NP) method is also conducted to compare with them. The tested results show that the weighted least square (WLS) is the most robust one among the spatial PR methods. At the same time, the temporal PR method is introduced based on the multi-frequency fringes, and the result proves that it features the better noise immunity and robustness than spatial ones, but needs many different frequencies of fringes that would be more time-consuming. Lastly, the surfaces are reconstructed in reverse engineering (RE) software.

According to the principle of optical design, two kinds of 2 Mega-pixel cell phone camera lenses are proposed. One is made up of three plastic (3P) lenses; the other is made up of two plastic lenses and one glass (2P1G) lens. The shapes of all lenses are aspheric. By comparison, the overall length of 2P1G lens is much less than that of 3P lens. Furthermore, in FOV the former is 5 degrees larger than the latter. At the same time, in distortion of the maximum field angle, the former is much less. The other aberrations of 2P1G lens are almost same to those of 3P lens. Therefore, in cell phone camera lens design, it’s recommended to adopt one aspheric glass lens to improve the performance and compactness though the cost will become a little higher due to the introduction of aspheric glass lens. However, the cost of aspheric glass lens could be reduced tremendously by a new cost-effective manufacturing method  compression molding technology.

In considering transmissibility of force and the output force of actuator, the transfer function was got between input excitations and out performance. Adopting different feedback control variable as velocity, force, full state etc, the H2 optimal control was applied to double layer isolation system. By analyzing the amplitude-frequency characteristics of transfer function, comparing the advantages and disadvantages of various feedback control strategy, the best control method of H2 is determined.

The chaotic dynamics system is so complex that the traditional methods of nonlinear numerical approximation can’t intuitively reflect the characteristics of chaotic behaviors. We propose a simple method for visualizing the phase space of chaotic dynamics system. With the help of the visualization technology based on VTK(Visualization Toolkit), we can quickly render the phase space of the system with different phase values and this can help us explore the inner rule of chaotic dynamics system.

Three models were established in this paper to analyses the strength of intact, damaged and reinforced pressure hull of ocean structure. Linear elasticity and elastoplasticity FEA method were adopted. The results showed that replacing rib and local reinforcing damaged pressure hull could not restore the performance of pressure structure. Other methods must be considered.

A pit with dimension 200mm×160mm×21mm is digged in the middle of steel plate using carbon-arc air gouging. The pit was polished and welded using CW66J welding rod. Built-in stress, toughness and rigidity was tested to validate the validity.

The dynamics and performance of hydropneumatic fender were studied. A theoretical model of the hydropneumatic fender was established to calculate its reaction forces and energy absorption capability. The influences of the length, diameter, volume percentage of water, and the internal air pressure upon the mechanical properties were analyzed. The reaction force and energy absorption capability of the hydropneumatic fender were numerically studied with the finite element analysis software MSC.Dytran. The numerical results were in agreement with the theoretical results, which showed that the theoretical model has well accuracy and is significative for the design of the hydropneumatic fender.

The nonlinear energy pumping in a two-degree-of-freedom system comprising a damped linear oscillator coupled to cubic damping absorber is studied. It is verified that the nonlinear pumping energy can be performed by cubic damping absorber besides cubic stiffness absorber. The resonance capture is verified by time-frequency analysis (Hilbert Transform). The energy pumping efficiency is put forward for quantitative analysis, and the optimal parameters of system are obtained. The amplitude of main oscillator can be attenuated in a very short duration. The result may be significative for engineering implementation.

On base of the electro-magneto-elastic theory and the theory of the bending vibration of the electric beam, nonlinear vibration equation of current-carrying beam subjected to thermal-magneto-elasticity field is studied. The Lorentz force and thermal force on the beam are derived. According to the method of multiple scales for nonlinear vibrations the approximation solution of the primary resonance of the system is obtained. Numerical analysis results show that the amplitude changed with the system parameters. With the decrease of magnetic intensity, the amplitude increases rapidly. The response curve occurs bending phenomenon and soft features is increased gradually. Increasing current, the amplitudes increase. With the decrease of temperature, the peak of response curves decrease. With the increase of temperature, natural frequency decreased. It is useful in practical engineering.

With the shaftless driving technology used in the packaging industry,servo motor control has become increasingly demanding. Beginning with the reasons of chattering, this article proposes a new sliding mode reaching law,adding a power attenuation term in front of the variable speed item,and then affects the shaftless gravure package printing chromatography system with PMSM as the actuator, improved servo motor speed range and efficency of the shaftless driving system.At last,the simulation results indicate the effectiveness of the proposed approach.