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Selection of secondary variables is an effective way to reduce redundant information and to improve efficiency in nonlinear system modeling. The combination of Kernel Principal Component Analysis (KPCA) and K-Nearest Neighbor (KNN) is applied to fault diagnosis of bearing. In this approach, the integral operator kernel functions is used to realize the nonlinear map from the raw feature space of vibration signals to high dimensional feature space, and structure and statistics in the feature space to extract the feature vector from the fault signal with the principal component analytic method. Assessment method using the feature vector of the Kernel Principal Component Analysis, and then enter the sensitive features to K-Nearest Neighbor classification. The experimental results indicated that this method has good accuracy.

Based on the concept of humanization design, some classification and analysis about user groups from user's age, gender, value, interests and economy were made in this paper. Due to the differences in ages, genders, values, interests and economy, different groups of users will have different styles and preferences. But users want to meet their psychological pursuit in the process of using the product. As the carrier of user groups, car design that can meet user’s demand has been discussed. Classify and categorize for users were made form user groups first, then design products that can mostly suitable for different user group and that the most they really demand for.Through taking full account of the needs of user groups and meeting user's emotional needs maximize, this products designed will be the products users wanted.

Elliptical vibration cutting (EVC) is one of the main methods to use diamond tool machining of hard to cutmaterial. Accurate prediction of cutting force in elliptical vibration cutting process is not only an important basis to properly choose of cutting parameters and optimal tool geometry parameters, but also a key factor to improve the processing property of cutting. A method to build cutting force theory model in EVC is presented in this paper. Eigen decomposition of the elliptic motion locus first,then getting the piecewise function of the cutting force model. Based on simulation analysis of the cutting force model, this paper predict the rules that vibration amplitude and angle of tool geometry affect on cutting force, which provide theory basis for choose cutting parameters and cutting tool parameter in EVC. (2013) Trans Tech Publications, Switzerland.

In order to study dynamic mechanical properties of float glass under blast and ballistic/fragmentation impacts, the curves of stress- strain are obtained in higher ranges by using the modified Split Hopkinson Pressure Bar (SHPB) techniques. Experimental results indicate that float glass is nonlinear elastic-brittle materials, and its dynamic curves of stress-strain are nonlinear and can be divided into three stages: elastic, nonlinear strengthening and stress drop. The dynamic Young’s modulus and the dynamic compressive strength of float glass increase with the increasing of strain rate. Finally, an explanation was given according to principle of energy equilibrium of Griffith.

In this paper, the probabilistic neural network and prediction thought are combined to evaluate hot rolling rhythm. An evaluation model of hot rolling rhythm based on PNN network is established. To verify the validity of the model and predicted results, the PNN network model is applied to practical production of a hot strip mill and proves to be a model of simple structure, fast calculation, high prediction accuracy and strong generalization ability, which is able to substitute for the conventional evaluation model based on the empirical formula and empirical data.

After heat treatment at 800°C for 15min, a Cu-Al alloy was cryogenic treated at -196°C for 30min, the micro-mechanical properties of the Cu-Al alloy before and after cryogenic treatment were measured by nanometer mechanical testing system and the microstructure of the Cu-Al alloy were also analyzed by optical microscope, SEM/EDS and XRD. On the basis of that, the effects of cryogenic treatment on micro-mechanical properties of the Cu-Al alloy were investigated. The results show that the cryogenic treatment can refine the grains, and increase the hardness, elastic modulus, elastic recovery rate and ratio of hardness to modulus of the Cu-Al alloy. As a result, cryogenic treatment can improve the ability to resist applied load and anti-indentation creep effectively.

Because of the traditional K-medoids clustering algorithm the initial clustering center sensitive, the global search ability is poor, easily trapped into local optimal and slow convergent speed; therefore, this article proposes an improved K-medoids clustering algorithm. Differential evolution is a kind of heuristic global search technology population, has strong robustness. Combined with K-medoids clustering algorithm efficiency and the global optimization ability of DE algorithm, not only can effectively overcome the detects of the K-medoids clustering algorithm, but also can raise the global search capability, short the convergence time, effectively improve the clustering quality. Finally, the algorithm is verified stability and robustness by simulation.

The transformation temperature and time of α+γ2 to ß in a Cu-Al alloy after cryogenic treatment during heating were measured by DSC, and the transformation activation energy of α+γ2 to ß was also calculated. It is indicated that the Cu-Al alloy with heating rate of 10°C/min, the phase transformation onset and ending temperature is 561.75°C and 582.88°C, respectively, and the phase transformation time is126.6S. The phase transformation activation energy decreases with the increasing volume fraction of their phase transformation.

A novel experimental apparatus of a liquid desiccant air-conditioning system was introduced. The system differed from similar researches in that it could handle the total load of the conditioned space without any refrigeration equipment and it worked in ventilation mode, which could greatly improve the indoor air quality. The schematic diagram of the system was presented and circulating processes of air, water and lithium chloride solution in the system were introduced. The definition of thermal coefficient of performance (TCOP) for the system was introduced and main operating parameters that could affect TCOP were analyzed. The tested TCOP of the system was 0.72～0.98 in summer and 0.30～0.51 in autumn, which showed that liquid discussant air conditioning system was especially suitable for hot and humid conditions.

According to GB150-1998, the standard of steel pressure vessel, determination method on design pressure and design temperature, material selection, tanks and the head design method and opening reinforcement calculation method was introduced. Running effects were in excellent condition after a few years of use. The design method of liquefied petroleum gas tanks was introduced in this paper had a guiding role on liquefied petroleum gas tank.

The conventional manufacture method is cold machining for thin board type parts, which has characteristic of process trival, energy consumption, long production period and the processing process easy to produce the deformation. To overcome these shortcomings, it usually was manufactured by stamping technology. So the cutting mould was designed on the analysis of the forming process for the type of parts, and adopted the unloading tendered a leaned way. Practice has proved that cutting the workpiece precision and quality is higher, cutting efficiency is high, the product quality completely meet the application requirements.

In recent years, water lubrication bearing has widely used in pump as support elements， its reliability and life have important influence on pump running, while the material of water lubrication bearing is one of main factors to limit its application. So integrating with its application of bearing lubrication for pump，the paper introduced the characteristics of the water lubrication friction pair and the wear mechanism of materials. Simultaneously characteristics and the scope of application of materials were introduced such as metal materials, plastic, ceramic, wood etc. The use principle and the future research direction was put forward for material of the water lubrication bearings.

In this study, monochlorotriazinyl-β-cyclodextrin (MCT-β-CD) was prepared from the reaction between cyanuric chloride and β-cyclodextrin (β-CD). The structure of the product was confirmed by FTIR, 1HNMR and ESI-MS. It is found that the yield of the MCT-β-CD was 61.72% and the average substitution degree (DS) of-OH in MCT-β-CD was 1.43. The water solubility of MCT-β-CD is 0.40 g/mL at room temperature.

For the problems of parameters disturbance, nonlinear and uncertainty of distribution static compensator (DSTATCOM), this paper studies on sliding mode control based on radial basis function (RBF) network. The fast tracking of DSTATCOM reactive current is achieved by using of RBF neural networks and equivalent sliding mode control. The method has a strong adaptability and robustness for load disturbances and system parameters change, and integrates the advantages of neural network and sliding mode control, so it is an ideal intelligent control strategy .The MATLAB simulation results show that the controller has good dynamic and static quality, and provides an effective way for improving the performance of DSTATCOM.

The extraction of natural dye from semen litchi was studied, and the stability and dyeing ability of the dyestuff for the silk fabrics were also investigated. The results showed that the extraction efficiency using ethanol and sodium hydroxide was better than other solvents. The results indicated that the stability of the semen litchi stuff was good. The optimum direct dyeing process is at 90°C for 45 min with pH 4. Meanwhile, the color yield and color fastness of dyed fabrics can be improved by mordant dyeing.

Precursor of tungsten was obtained by spray drying process with high purity APT crystal liquor as material. The precursor was analysized by electron microscopy and X-ray. A suitable spray drying process was found through the morphology and powder structure. The influence of atomization disk rotational speed, the concentration ratio of ammonia to WO3 in APT liquor and APT liquor’s concentration on particle size, structure and morphology of the ball precursor were studied. Uniformity superfine WO3 was obtained from precursor by calcined.

A new decoupling control structure is presented for complex special shape pipe welding process, which consists of model construction by reorganization method. Using this structure, an decoupling control system is established which realizes an adaptive decoupling control strategy for the welding processes with integrated complexities by using structure of decoupling control system and based on multivariable predictive function and nash optimization to making sure the right coefficient. Such system can be easily implemented on the welding peocess and simulation show this approach is effective.

In order to reduce the silicon content to the maximum allowed value for the production of high-purity titanium dioxide, a hydrometallurgical process on the desiliconization during alkaline leaching of titanium slag under atmospheric pressure was studied. The effect of leaching temperature, initial NaOH concentration, leaching time and mass ratio of alkali to slag, on the efficiency of silicon removal were investigated. The results show that when the mass concentration of NaOH is 30%, mass ratio of alkali to slag 3:1, the leaching temperature 120°C and the retention time about 120min, the content of silicon in solid is reduced to 0.45%. Simultaneously, the content of aluminum is reduced to 1.62%, without affecting the content of titanium. The kinetics on the desiliconization during alkaline leaching of titanium slag was carried out. The results show that under the leaching parameters mentioned above, the apparent activation energy is calculated to be 45.43kJ/mol.

In this present paper a new yield criterion called M-D criterion is established based on the average of Mohr-Coulomb and Drucker-Prager criterion. The new M-D criterion is integrated with a revised FLAC3D method for mechanical analysis. Comparisons between the results of M-D, Mohr-Coulomb and Drucker-Prager are made by cases study. The study shows that results of M-D criterion are basically between the results of Mohr-Coulomb and Drucker-Prager and have the feature of being medial in quantity.

B4C ceramic nozzle was produced by hot pressing, and wear behavior of the nozzle by SiC, white emery and umber emery abrasives were investigated, erosion wear mechanisms based on stress states analyzing with finite element method were studied. Results showed that the greater the hardness and grit size of abrasives, the more mess loss of the nozzle, the maximum stress appeared in entrance area of the nozzle and minimum stress in middle area, while the stress of exit area was lower than entrance area and higher than middle area. The nozzle exhibited a brittle fracture induced removal process in the entrance of the nozzle and a stress fatigue induced removal process in the middle of the nozzle under the condition of SiC abrasives impacting, and a stress fatigue induced removal process under white and umber emery abrasives impacting.

Arc ion plating technique PVD ZrN coatings were deposited on YT15 cemented carbide. Microstructural and fundamental properties of the ZrN coatings were examined. The ZrN coated tools (DZ and GZZ) showed much better cutting performance compared to the YT15 uncoated cemented carbide, which is connected with their large hardness increase, and good abrasive wear resistance. The wear surface features of the coatings were examined by scanning electron microscopy. Results showed that the PVD ZrN coatings onto the cemented carbide substrate show high hardness and good adhesion with the substrate. Abrasive wear was found to be the predominant flank wear mechanism for the ZrN coated tools. While the mechanisms responsible for the rake wear were determined to be adhesion.

Effects of high pressure heat treatment on the microstructure refinement and corrosion resistance of brass were studied by means of metallographic observation, SEM/EDX, profilometer and CH1660A electrochemical instrument. Brass were heated from 23°C to 700°C and kept at 700°C for 10 minutes under high pressure of 1GPa, 3GPa, 4GPa and 6GPa, respectively. The results show that high pressure heat treatment has great influence not only on the microstructure refinement of the alloy but also on its corrosion resistance in HCl solution. Under 3GPa, the refined microstructure can be found and the corrosion resistance of the alloy changes into much worse. However, under a higher pressure of 6GPa, the corrosion resistance increases and the microstructure refining effect is not obvious. All the findings of this work were elucidated in terms of the change in the formation and growing of the crystal under a high pressure heat treatment condition.

Various elements in planetary gear reducer design are discussed. A multi-objective optimization model is created. The model requires the minimum volume and the maximum contact ratio. The method of multiplication and division is used to solve the multi-objective problem, and the method of feasibility enumeration is used to handle the discrete variables. The results show that the optimal solution meets the actual requirements.

The influence of deformation on dechromization of CuCr alloy in H3PO4 solutions was investigated by static immersion corrosion tests. The properties of undeformed and deformed alloys were characterised by XRD, Metallograph, SEM and X-ray fluorescence spectrometer respectively. It is observed that the deformation plays an important role in dechromization of CuCr alloys in H3PO4 solutions. Compared with undeformed one, the deformed CuCr alloy’s incubation time of corrosion is shortened, the concentration and temperature of H3PO4 solutions needed for dechromization decrease. Consequently the tendency of dechromization increases. Surface analysis showed that the microstructure of the dechromization layer is scarcely influenced. Finally, the dechromisation mechanism was discussed.

The toughening for UPR composite effect of rigid nano-particles was studied. By the tensile test, it was confirmed that with the increase of the organic rigid particle PA6 and inorganic rigid nano-particles SiO2，toughening effect for the UPR was better. The Generalized Method Cell of the micro-mechanical constitutive of the rigid particles and UPR phase was established. The macro- plastic deformation was simulated by the correlation of parameters for micro-mechanical and macroscopic mechanical, the simulation curves were well fit with its experimental curves。The numerical results indicate that the nonlinear theoretical method can simulate the plastic strain curves of composite well.

The electrochemical compatibility between natural graphite and garnet-like Li6BaLa2Ta2O12 or organic electrolytes was investigated. The formation of solid electrolyte interface (SEI) films in the initial cycle was investigated by galvanostatic charge and discharge, cyclic voltammetry experiments. The experimental results show that electrochemical compatibility between natural graphite and Li6BaLa2Ta2O12 is the most excellent, while electrochemical compatibility between natural graphite and PC-based electrolytes are the poorest. In the initial cycle, the discharge capacity and charge-discharge efficiency are both the highest in Li6BaLa2Ta2O12 electrolyte, and they are 337.1 mAhg-1 and 99.5 %, respectively.

Ni/Al2O3 composite coatings were prepared by direct current (DC), single pulse current (PC) and pulse reversal current (PRC), respectively. The hardness and wear resistance of the coatings were investigated and the morphology and elements distribution in cross-section were analyzed by the application of SEM/EDS, XRF and XRD equipped with stress measuring device. The results show that the hardness of the three kinds of coatings increase with increasing Al2O3 content. The coating prepared by PRC plating exhibits higher hardness and better wear resistance, while that of DC plating has lower hardness and poorer wear resistance. The higher hardness and better wear resistance of coating of PRC plating can be ascribed to fine microstructure and weaker stress between substrate and coatings.

The synergistic toughening of UPR composite by rigid particles of organic PA6 and inorganic nano-SiO2 was studied. The effects of PA6 and SiO2 on the notched impact and tensile strength of the UPR composite were studied by means of the mechanical properties test. The experimental results indicated that the notched impact strength was improved and its effect was evident when 7-9％rigid particles were applied and the tensile strength was improved when the 2-5％ rigid particles were applied. The composite of PA6/SiO2 ( 2/1) exhibited good mechanical property in the synergistic toughening. By the micromechanical analysis of composite, we thought that the stiffness of composite materials was determined by the stress suffered the rigid particles and the deformation of UPR polymer phase.